JP6699078B2 - Battery charger for power tools - Google Patents

Description

  The present invention relates to a battery pack charger for an electric power tool, which charges a battery pack for an electric power tool including a secondary battery such as a nickel/cadmium battery, a nickel/hydrogen battery, or a lithium ion battery.

  Conventionally, a battery pack has been used as a power source for electric tools and the like, and the battery pack is charged by a dedicated charging device. As a battery pack used for an electric power tool or the like, a battery pack having a large battery capacity and a high discharge voltage is used. In recent years, the capacity has been further increased, and a high capacity battery pack having a nominal capacity of 5 Ah or more has been introduced.

  On the other hand, a charging device described in Patent Document 1 is known as a charging device that charges a battery pack having a nominal capacity of less than 5 Ah with a charging current of 2 C or more.

JP, 2008-104349, A

  However, the charging device described in Patent Document 1 does not consider charging a high capacity (5 Ah or more) battery pack. Further, in a configuration in which a high-capacity (5 Ah or more) battery pack is charged with the same charging current as a conventional capacity (less than 5 Ah) battery pack, it takes a long time to charge the high-capacity battery pack, and the charging time Was difficult to shorten. In addition, a configuration may be considered in which charging is performed with a relatively large charging current with respect to the nominal capacity of a high-capacity battery pack, and the charging time is shortened. There is also a problem that the charging current is interrupted by the interrupting means (fuse, thermal protector, etc.), and the charging is interrupted or terminated, so that the charging time cannot be shortened as a result.

  Therefore, an object of the present invention is to provide a charging device capable of charging a high capacity battery pack in a short time.

In order to solve the above problems, the present invention is provided with a case in which an intake port for taking in air and an exhaust port for exhausting air are formed, a battery pack can be mounted, a fan for generating cooling air in the case, and A charging circuit unit that is provided in the case and configured to charge the battery pack, and has a plurality of heating elements that generate heat when the battery pack is charged; and the plurality of heating elements include at least a first Heat generating element, a second heat generating element, and a third heat generating element, and a heat radiating member for radiating the heat of the heat generating element is attached to each of the first heat generating element and the second heat generating element. The two heat radiating members are arranged so as to extend in opposition to each other so that the cooling air flows linearly between the two heat radiating members from the intake port toward the exhaust port. The charging device is characterized in that the third heating element is disposed between the charging device and the charging device.
In the above structure, it is preferable that the fan is arranged between the two heat radiating members in an extension of a direction in which the two heat radiating members extend.
In the above structure, it is preferable that the fan is arranged downstream of the third heating element in a direction in which the cooling air flows.
In the above configuration, at least one of the first heating element and the second heating element is preferably arranged between the two heat radiation members.
In the above structure, it is preferable that the two heat radiating members have dimensions larger than those of the third heat generating element in a direction in which the cooling air flows between the two heat radiating members.
In the above structure, a second fan is further provided, and the case is provided with a battery mounting portion on the upper surface of which the battery pack is mounted and an opening through which air for cooling the battery pack passes. The second fan is preferably arranged below the battery mounting portion and configured to generate cooling air for cooling the battery pack through the opening.
In the above structure, it is preferable that the cooling air generated by the second fan flows through a different air passage from the cooling air generated by the fan.
In the above-mentioned configuration, it is preferable that the intake port and the exhaust port are formed on both sides of the case with the charging circuit section interposed therebetween.
In order to solve the above problems, the present invention further provides a battery pack for a power tool, which is capable of charging a battery pack for a power tool including a secondary battery, wherein the battery pack having a nominal capacity of 5 Ah or more is 2C. Provided is a charging device for a battery pack for an electric tool, which is configured to be charged with the above charging current.

  With such a configuration, a high-capacity battery pack having a nominal capacity of 5 Ah or more can be charged with a charging current of 2 C or more, so that the high-capacity battery pack can be charged in a short time of about 30 minutes. it can.

  In order to solve the above-mentioned problems, the present invention is a battery pack for a power tool, which is capable of charging a battery pack for a power tool including a secondary battery, and has a nominal capacity of α (α is 5 or more). Provided is a battery pack charger for an electric power tool, wherein the battery pack having a real number of Ah or more can be charged with a charging current of 2αA or more.

  With such a configuration, a high-capacity battery pack having a nominal capacity of α (α is a real number of 5 or more) Ah or more can be charged with a charging current of 2αA or more, and therefore in about 30 minutes in a short time. A high capacity battery pack can be charged.

  In the above structure, the battery pack further includes a cutoff unit that allows the charging current to flow to the secondary battery when the predetermined condition is satisfied and cuts off the charging current when the predetermined condition is not satisfied. A charging control means for specifying a predetermined condition of a battery connecting portion connectable to the battery pack and the shutoff means of the battery pack connected to the battery connecting portion, and performing charge control so as to satisfy the predetermined condition. And are preferably provided.

  According to such a configuration, the charging control means performs the charging control so as to satisfy the predetermined condition of the cutoff means, so that the charging current is not cut off by the cutoff means and the charging is not interrupted or terminated. Therefore, a high capacity battery pack can be charged with a relatively large charging current, and a high capacity battery pack can be charged in a short time.

  In order to solve the above problems, the present invention further includes a secondary battery, and when the predetermined condition is satisfied, the charging current is allowed to flow in the secondary battery, and the charging current is satisfied when the predetermined condition is not satisfied. A charging device for a power tool battery pack capable of charging a power tool battery pack, comprising: a disconnecting means for disconnecting the battery pack, the battery connecting portion being connectable to the battery pack, and the battery connecting portion being connected to the battery connecting portion. A charging device for a battery pack for an electric power tool, comprising: a charging control unit that specifies the predetermined condition of the cutoff unit of the battery pack and performs charging control so as to satisfy the predetermined condition. ..

  According to such a configuration, the charging control means performs the charging control so as to satisfy the predetermined condition of the cutoff means, so that the charging current is not cut off by the cutoff means and the charging is not interrupted or terminated. Therefore, a high capacity battery pack can be charged with a relatively large charging current, and a high capacity battery pack can be charged in a short time.

  In the above configuration, it is preferable that the battery pack having a nominal capacity of 5 Ah or more can be charged with a charging current of 2 C or more.

  With such a configuration, a high-capacity battery pack having a nominal capacity of 5 Ah or more can be charged with a charging current of 2 C or more, so that the high-capacity battery pack can be charged in a short time of about 30 minutes. it can.

  Further, it is preferable that the battery pack having a nominal capacity of α (α is a real number of 5 or more) Ah or more can be charged with a charging current of 2αA or more.

  With such a configuration, a high-capacity battery pack having a nominal capacity of α (α is a real number of 5 or more) Ah or more can be charged with a charging current of 2αA or more, and therefore in about 30 minutes in a short time. A high capacity battery pack can be charged.

  Further, the predetermined condition is satisfied when the charging current is smaller than an allowable maximum current value corresponding to the battery temperature of the secondary battery, and the charging control means is a battery that acquires the battery temperature of the battery pack. Temperature acquisition means, current setting means capable of setting one current value among a plurality of current values, and current control means for controlling the charging current so as to charge the battery pack at the set one current value. And charging based on the battery temperature so as to charge the battery pack with a maximum current value among current values smaller than an allowable maximum current value among the plurality of settable current values. It is preferable to control the current.

  With such a configuration, it is possible to charge the battery pack based on the battery temperature at the maximum current value among the current values that are smaller than the allowable maximum current value of the plurality of settable current values. That is, the battery pack can be charged with the maximum current value among the current values that satisfy the predetermined condition. Therefore, the charging time can be further shortened.

  Further, it is preferable that the allowable maximum current value under the predetermined condition becomes smaller as the battery temperature becomes higher, and the charging control means makes the charging current smaller as the battery temperature becomes higher.

  According to such a configuration, the charging current can be changed according to a predetermined condition, that is, the breaking characteristic of the breaking means, so that the breaking of the charging current by the breaking means can be reliably avoided. Thereby, the charging time can be surely shortened.

  Further, when the battery temperature becomes equal to or higher than the first temperature threshold value when the charging control means is charging at the first current value, the charging current is controlled so as to charge at the second current value smaller than the first current value. The first temperature threshold value is preferably lower than the first battery temperature at which the corresponding maximum allowable current value is the first current value.

  With such a configuration, it is possible to more reliably avoid the interruption of the charging current by the interruption means. More specifically, the maximum permissible current value corresponding to the first battery temperature is the first current value, and when charging is performed at the first current value, when the battery temperature reaches the first battery temperature, the cutoff unit operates. Although the charging current is interrupted, the charging current by the interrupting means is changed because the battery current changes from the first current value to the smaller second current value when the battery temperature reaches the first temperature threshold value lower than the first battery temperature. Can be more reliably avoided.

  In addition, the charging control means, when charging with the second current value, when the battery temperature becomes equal to or higher than a second temperature threshold value higher than the first temperature threshold value, a third value smaller than the second current value value. The charging current is controlled to charge at a current value, the second temperature threshold is lower than the second battery temperature at which the corresponding maximum allowable current value is the second current value, and the first battery temperature is Is preferably higher than.

  With such a configuration, it is possible to more reliably avoid the interruption of the charging current by the interruption means and further reduce the charging time. More specifically, since the second temperature threshold value for changing the charging current from the second current value to the smaller third current value is lower than the second battery temperature, it is possible to reliably avoid the operation of the cutoff unit. it can. Furthermore, the second temperature threshold value is not higher than the first battery temperature, that is, not too low. If the second temperature threshold value is set to an excessively low value, for example, if it is set to a value lower than the first battery temperature, the operation of the cutoff unit can be reliably avoided, but the charging current is set to the second value. Since the timing of changing the current value to the smaller third current value is advanced, the charging time cannot be shortened sufficiently. In this respect, by setting the second temperature threshold value higher than the first battery temperature as in the above configuration, the timing of changing to a smaller current value can be delayed, and the charging time can be further shortened.

  Further, it is preferable that the blocking means is a thermal protector.

  Further, the breaking means is preferably a fuse.

  In addition, it is preferable that a plurality of battery packs having different voltages and different nominal capacities can be selectively charged, and a battery pack having a nominal capacity of less than 5 Ah can be charged with a charging current of 2 C or more. ..

  With such a configuration, a battery pack of less than 5 Ah can be charged rapidly.

  In order to solve the above problems, the present invention further provides a battery pack for a power tool, which is capable of directly charging a battery pack for a power tool including a secondary battery from a commercial AC power supply, and has a nominal capacity of 5 Ah or more. Provided is a battery pack charging device for an electric power tool, wherein the battery pack can be charged with a charging current of 2C or more and 3C or less.

In order to solve the above problems, the present invention further provides a battery pack for a power tool, which is capable of directly charging a battery pack for a power tool including a secondary battery from a commercial AC power supply, and has a nominal capacity of α(α Provides a battery pack charger for an electric power tool, wherein the battery pack having a real number of 5 or more) Ah or more can be charged with a charging current of 2αA or more and 3αA or less.
In order to solve the above-mentioned problems, the present invention further has a battery connecting portion connectable to a battery pack for an electric power tool including a secondary battery, and an electric motor capable of charging the battery pack connected to the battery connecting portion. A charging device for a battery pack for tools, which is configured to be capable of charging the battery pack having a nominal capacity of 5 Ah or more with a charging current of 2 C or more, and the battery pack is provided with the secondary battery when a predetermined condition is satisfied. A charging means for allowing the charging current to flow through the battery pack and cutting off the charging current when the predetermined condition is not satisfied, and satisfies the predetermined condition of the breaking means of the battery pack connected to the battery connecting portion. Thus, there is provided a charging device for a battery pack for an electric tool, which is provided with a charging control means for changing the charging current.
In order to solve the above problems, the present invention further allows a secondary battery and a charging current to flow to the secondary battery when the predetermined condition is satisfied, and the charging current when the predetermined condition is not satisfied. A battery pack for a power tool capable of charging a battery pack for a power tool, comprising: a disconnecting unit for disconnecting the battery pack, the battery connecting section being connectable to the battery pack, and the battery connecting section being connected to the battery connecting section. And a charging control means for changing the charging current so as to satisfy the predetermined condition of the cutoff means of the battery pack.

  According to the charging device of the present invention, a high capacity battery pack can be charged in a short time.

The external view of the charging device by the 1st Embodiment of this invention. The top view of the charging device shown in FIG. The side view of the charging device shown in FIG. The top view which shows the charging circuit part in the case of the charging device shown in FIG. The side view of the charging device shown in FIG. 1 which charges a battery pack. FIG. 2 is a perspective view showing a heat dissipation member, a charging circuit unit, first and second fans inside the charging device shown in FIG. 1. The front view of the charging device shown in FIG. 1 which charges a battery pack. It is a figure explaining the relationship between a heat dissipation member and cooling air, (a) explains the flow of cooling air when there is no 2nd heat dissipation part, (b) explains the flow of cooling air when there is a 2nd heat dissipation part. Figure to do. FIG. 2 is a circuit diagram including a block diagram showing an electrical configuration of the charging device shown in FIG. 1, showing a state in which a battery pack is mounted in a battery mounting portion. The figure which shows the 1st interruption|blocking characteristic curve which the 1st interruption|blocking element with which the battery pack shown in FIG. 9 has is provided. The figure which shows the 2nd interruption|blocking characteristic curve which the 2nd interruption|blocking element with which the battery pack shown in FIG. 9 has is provided. The flowchart which shows the charge process by the charge control part of the charging device shown in FIG. The flowchart which shows the charge process by the charge control part of the charging device shown in FIG. 10 is a table for determining a target current value used when the charging control unit of the charging device shown in FIG. 9 charges a battery pack. (A) And (b) is a time chart which shows the time change of battery temperature, charge voltage, and charge current at the time of performing charge control by the charge control part of the charging device shown in FIG. (C) is a time chart showing changes over time in battery temperature, charging voltage, and charging current when charging control is performed by a conventional charging device. The top view which shows the inside of the charging device which shows the modification of 1st Embodiment. FIG. 17 is a perspective view of a heat dissipation plate in the modification example shown in FIG. 16. FIG. 17 is a perspective view showing the relationship between the heat dissipation plate shown in FIG. 16 and the defined air passage. The figure explaining the flow of the cooling wind in the charging device shown in FIG. 16 at the time of charging a battery pack. The figure explaining the flow of the cooling wind in the charging device shown in FIG. 16 at the time of charging a battery pack. The top view which shows the charging circuit part in the case of the charging device by the 2nd Embodiment of this invention. The side view of the charging device shown in FIG. The top view which shows the modification of 2nd Embodiment. The top view which shows the modification of 2nd Embodiment. The side view which shows the modification of 2nd Embodiment. The side view which shows the modification of 2nd Embodiment. The top view which shows the modification of 2nd Embodiment. The top view which shows the modification of 2nd Embodiment. The top view of the charging device by the 3rd Embodiment of this invention. The flowchart which shows the 1st charging operation of the charging device by the 3rd Embodiment of this invention. The figure explaining the 1st cooling wind produced when driving only a 1st fan in the charging device shown in FIG. The figure explaining the 2nd cooling wind produced when driving only a 2nd fan in the charging device shown in FIG. FIG. 30 is a plan view showing first and second cooling winds generated in the case when the charging device shown in FIG. 29 charges the battery pack. The flowchart which shows the 2nd charging operation of the charging device by the 3rd Embodiment of this invention. The figure explaining the cooling air which flows into a case when the rotation speed of a 1st fan is larger than the rotation speed of a 2nd fan in the charging device shown in FIG. The figure explaining the cooling air which arises in a case when the rotation speed of a 2nd fan is larger than the rotation speed of a 1st fan in the charging device shown in FIG. The side sectional view which shows the inside of the charging device by the 4th Embodiment of this invention. The top view of the charging device shown in FIG. The top view of the charging device by the 5th Embodiment of this invention.

  A charging device according to an embodiment of the present invention will be described with reference to the drawings. In the following description, the direction in which the surface on which the battery pack is attached to the charging device faces is defined as the upward direction, and the opposite direction is defined as the downward direction. The left-right direction and the front-back direction are the directions shown in the drawings unless otherwise specified.

  The charging device 1 according to the first embodiment of the present invention charges a plurality of types of battery packs including the battery packs 3 and 33, that is, a plurality of battery packs having different battery types (battery pack voltage, nominal capacity) from each other. It is configured to be possible. In the following description, the case where the battery pack 3 is attached to the charging device 1 will be mainly described, and the battery pack 33 will be appropriately described together with the description of the battery pack 3.

  Referring to FIGS. 1 to 5, a charging device 1 includes a charging circuit unit 4 for charging a battery pack 3 and a plurality of fans for cooling the charging circuit unit 4 and the battery pack 3 inside a case 2. The first fan 5 and the second fan 6 are provided.

  The case 2 has a substantially rectangular parallelepiped shape, and the upper surface 21 is provided with a battery mounting portion 7 to which the battery pack 3 is mounted for charging on the front side. The battery mounting portion 7 is provided with a plurality of terminals 70 for charging the battery pack 3 and an opening 71 through which air for cooling the battery pack 3 passes. Further, the case 2 has four side surfaces 22, 23, 24, 25 surrounding the upper surface 21 and a bottom surface 27 located on the side opposite to the upper surface 21, and the side surfaces 22, 23 adjacent to each other form a corner portion 26. Are linked together. The side surfaces 22 and 24 face each other, and the side surfaces 23 and 25 face each other. In the case 2, the direction from the bottom surface 27 to the upper surface 21 is the upward direction of the charging device 1, that is, the first direction intersecting the upper surface.

  As shown in FIG. 4, the first fan 5 is arranged in the case 2 close to the corner portion 26 and the opening 71 and close to the side surface 22. The first fan 5 has a first rotating shaft 5a. In addition, a first exhaust port 22a including a plurality of ventilation windows is formed on the side surface 22 facing the first fan 5. When driven, the first fan 5 generates the first cooling air in the direction of the first rotating shaft 5a. The first cooling air flows toward the first exhaust port 22a and is exhausted from the case 2 via the first exhaust port 22a.

  As shown in FIG. 4, the second fan 6 is arranged in the case 2 close to the corner portion 26 and the opening 71 and close to the side surface 23. The second fan 6 has a second rotating shaft 6a. The second fan 6 is arranged such that the extension direction of the second rotation shaft 6a intersects the extension direction of the first rotation shaft 5a of the first fan 5. A second exhaust port 23a composed of a plurality of ventilation windows is formed on the side surface 23 facing the second fan 6. When driven, the second fan 6 generates the second cooling air in the direction of the second rotating shaft 6a. The second cooling air flows toward the second exhaust port 23a and is exhausted from the case 2 via the second exhaust port 23a. Therefore, the plurality of fans (first fan 5 and second fan 6) can enhance the cooling efficiency of the heating elements in the charging device 1. Further, by disposing the fans 5 and 6 along the side surfaces of the case 2 (specifically, the side surfaces 22 and 23), the installation space of the board 40 in the case 2 can be secured and the board 40 can be effectively used. .. In particular, it is effective to provide the case 2 in the vicinity of the corner connecting the side surfaces.

  In the case 2, a plurality of ventilation windows are formed as intake ports 24a on a side surface 24 opposite to the side surface 22 over a predetermined range. Therefore, when the first fan 5 and the second fan 6 are driven, the air is taken into the case 2 from the intake port 24a, and the taken-in air is used as the first and second cooling air inside the case 2. It passes along the cooling air passage and is exhausted to the outside of the case 2 through the first and second exhaust ports 22a and 23a. The details of the cooling air passage will be described later.

  The charging circuit unit 4 includes a substrate 40 arranged near the intake port 24a in the case 2, mainly including a diode 41, a transformer 42, a FET 43, a temperature detection element 44, and a charging control unit 45. It is implemented and configured. Under the control of the charging control unit 45, the charging circuit unit 4 charges the battery pack 3 via the terminal 70 using the electric power supplied from the commercial AC power source P, for example. When a large amount of current is supplied to the charging circuit unit 4 for a large current and rapid charging, that is, so-called 2C charging, the diode 41, the transformer 42, and the FET 43 tend to generate heat. In order to protect these parts from heat generation and promote heat dissipation, heat dissipation members 46 and 47 are attached to the diode 41 and the FET 43, respectively.

  Further, the diode 41, the transformer 42, and the FET 43 are arranged near the intake port 24a so that they are directly exposed to the air introduced into the case 2 from the intake port 24a. In particular, the transformer 42 is arranged on the most upstream side of the cooling air passage, that is, near the intake port 24a.

  The heat dissipation member 46 is formed of a metal having a high thermal conductivity, and extends from the substrate 40 toward the upper surface 21, that is, in the first direction and has the plate-shaped first heat dissipation member 41 fixed thereto as shown in FIG. The portion 46A and a plate-shaped second heat radiation portion 46B extending from the tip of the first heat radiation portion 46A toward the heat radiation member 47 substantially parallel to the upper surface 21. The direction in which the second heat radiation portion 46B extends is the direction intersecting the first direction, that is, the second direction. Therefore, the heat dissipating member 46 is formed to have a substantially L-shaped cross section in a side view.

  Similarly, the heat dissipation member 47 is also formed of a metal having a high thermal conductivity, and extends from the substrate 40 toward the upper surface 21 in the first direction in the first direction to fix the FET 43, as shown in FIG. The portion 47A and a plate-shaped second heat radiation portion 47B extending in the second direction toward the heat radiation member 46 from the tip of the first heat radiation portion 47A substantially in parallel to the upper surface 21. Therefore, the heat dissipating member 47 is formed so that its cross-sectional shape is substantially L-shaped in a side view.

  As shown in FIG. 6, when the heat radiation members 46 and 47 are mounted on the substrate 40, one ends of the first heat radiation portion 46A and the first heat radiation portion 47A are spaced apart from each other and are located in the vicinity of the intake port 24a. Is located in. Further, the second heat radiating portions 46B and 47B are arranged so as to be separated from the transformer 42 by a predetermined distance defined by the standard so as to sandwich the transformer 42 therebetween. Further, as shown in FIG. 5, the second heat dissipation portion 46B and the second heat dissipation portion 47B are located between the diode 41 and the FET 43 and the upper surface 21 in the first direction. The first and second heat radiating portions 46A and 46B of the heat radiating member 46 and the first and second heat radiating portions 47A and 47B of the heat radiating member 47 are formed in such a size as to have an appropriate insulation distance from the transformer 42. ing.

  Further, when the heat dissipation members 46 and 47 are mounted on the substrate 40, the heat dissipation members 46 and 47 together with the substrate 40 define an air passage for the air taken into the case 2 from the intake port 24a, and the diode 41 is provided in the air passage. , The transformer 42, and the FET 43.

  The temperature detection element 44 is composed of, for example, a thermistor, and detects the temperature inside the case 2.

  The charge control unit 45 controls the charging of the battery pack 3 by the charging circuit unit 4 while monitoring the temperature of the battery pack 3, and also controls the rotation of the first and second fans 5 and 6.

  In the charging device 1, when the battery pack 3 is attached to the battery mounting portion 7 as shown in FIG. 7, the first fan 5 and the second fan 6 are driven. By driving the fan, the first cooling air and the second cooling air are generated in the case 2 to form a cooling air passage from the intake port 24a to the first exhaust port 22a and the second exhaust port 23a.

  In the vicinity of the intake port 24a, the cooling air passage is provided on the upper surface as shown in FIG. 6 by the first heat radiation portions 46A, 47A and the second heat radiation portions 46B, 47B of the heat radiation members 46, 47 and the substrate 40. The part is defined as a duct having an opening. Therefore, the first cooling air and the second cooling air flow from the one end side close to the intake port 24a of each of the first heat radiation parts 46A, 47A toward the other end side close to the exhaust ports 22a, 23a. Proceed within.

  Cooling air generally tends to pass from the intake port 24a toward the exhaust ports 22a and 23a at the shortest distance. Therefore, when the second heat dissipation portion 46B is not provided, as shown in FIG. 8B, most of the cooling air does not flow from one end of the heat dissipation member 46 to the other end thereof, and the heat dissipation member 46 is provided. To reach the exhaust ports 22a and 23a. Therefore, the first cooling air or the second cooling air does not pass by the diode 41, the transformer 42, and the FET 43 arranged between the heat dissipation members 46 and 47, and the diode 41, the transformer 42, and the FET 43 are sufficiently cooled. It will not be possible.

  On the other hand, in the embodiment of the present invention, as shown in FIG. 8(a), the cooling air is provided by the second heat radiating portions 46B, 47B extending in the second direction from the respective tip portions of the first heat radiating portions 46A, 47A. However, it is prevented from flowing over the first heat radiation portion 46A to the exhaust ports 22a and 23a. For this reason, the cooling air flows from one end of each of the first heat radiating portions 46A and 47A toward the other end thereof, so that the cooling air flows near the diode 41, the transformer 42, and the FET 43 arranged between the heat radiating members 46 and 47. The diode 41, the transformer 42, and the FET 43 can be sufficiently cooled by passing through.

  Note that the arrangement of the diode 41, the transformer 42, and the FET 43 in the cooling air passage defined by the heat dissipation members 46 and 47 shown in FIGS. 4, 5, and 6 is an example, and the first cooling air and the second cooling air Can be arranged appropriately if it passes by the element. In addition, the cooling air uses the exhaust ports 22a and 23a provided in the vicinity of the first fan 5 and the second fan 6 as the intake ports and the intake port 24a as the exhaust ports to blow air into the case 2 by the fans 5 and 6. It may be configured to be incorporated in the. However, in this case, since the cooling air is blown to the heating elements, the cooling effect is lower than that of the case where the air is discharged to the outside of the case 2 by the first fan 5 and the second fan 6. Since the cooling air is focused near the port 24a (used as an exhaust port), it is possible to cool the heating element (transformer 42 or the like) arranged near the intake port 24a with a high air volume. In addition, dust may be sucked together with air by the first fan 5 and the second fan 6 and clogged in the exhaust ports (22a, 23a). Therefore, by adopting a configuration in which the air is discharged to the outside of the case 2 by the first fan 5 and the second fan 6, it is possible to enhance the cooling efficiency of the heating element and suppress clogging of the exhaust ports (22a, 23a). can do.

  Further, in order to cool the battery pack 3, a duct 90 shown in FIG. 7 also forms an air passage between the opening 71 and the first exhaust port 22a and the second exhaust port 23a. The duct 90 separates the cooling air passage of the battery pack 3 from the cooling air passage of the charging device 1. That is, the air taken into the battery pack 3 from the intake port of the battery pack 3 and taken into the charging device 1 through the opening 71 passes through the upper side of the duct 90 and is discharged from the first exhaust port 22a and the second exhaust port 23a. Is discharged. On the other hand, the air taken into the charging device 1 from the intake port 24a does not flow to the battery pack 3 side by the duct 90, passes through the lower side of the duct 90, and is discharged from the first exhaust port 22a and the second exhaust port 23a. The duct 90 is omitted in FIG.

  Here, the electrical configuration of the charging device 1 and the battery packs 3 and 33 connected to the charging device 1 according to the first embodiment will be described with reference to FIG. 9. The battery pack 3 and the battery pack 33 are different in battery type from each other, and different in the cutoff element, the allowable charging current value and the internal resistance (nominal capacity) of the battery group, etc. The communication method and the like with 1 are the same. Therefore, the battery pack 3 will be described as an example, and only the differences of the battery pack 33 will be described. FIG. 9 is a circuit diagram including a block diagram showing an electrical configuration of the charging device 1, the battery packs 3 and 33, and shows a state in which the battery pack 3 or 33 is mounted on the battery mounting portion 7.

  First, the electrical configuration of the battery pack 3 will be described. The battery pack 3 is a battery pack having a high capacity (nominal capacity of 5 Ah or more) configured to be attachable to and detachable from an electric tool such as a hammer drill and a portable circular saw, and used as a power source for driving the electric tool. As shown in FIG. 9, the battery pack 3 includes a battery set 3A, a connection terminal portion 3B, a protection IC 3C, a battery side power supply circuit 3D, a battery temperature detection circuit 3E, and a first cutoff element 3F. The battery side controller 3G is provided. The battery capacity may be the rated capacity.

  The battery group 3A has a configuration in which four battery cells 3a are connected in series. In the present embodiment, for example, battery cell 3a is a lithium-ion battery, the nominal voltage is 3.6V, the maximum charging voltage is 4.2V, and the maximum charging voltage of battery group 3A is 16.8V (4. 2V/cell×4 cells). Further, the battery group 3A has a nominal capacity of 6 Ah and an allowable charging current value of about 12 A (or 2 C), which is a high capacity as a drive power source for an electric tool. The allowable charging current value is the maximum value of the charging current that can be charged without the risk of deterioration or failure of the battery group 3A, and 12A (2C) is only an example, and may be more. For example, a high-performance battery cell may have an allowable charging current value of 12A (2C) or more. The battery cell 3a is an example of the "secondary battery" in the present invention.

  The connection terminal portion 3B has a positive connection terminal 3b and a negative connection terminal 3c. The positive connection terminal 3b is connected to the positive terminal of the battery cell 3a having the highest potential via the first blocking element 3F. The negative connection terminal 3c is connected to the negative terminal of the battery cell 3a having the lowest potential. When the battery pack 3 is mounted in the battery mounting portion 7 of the charging device 1, each of the positive connection terminal 3b and the negative connection terminal 3c is connected to a predetermined terminal of the plurality of terminals 70 of the charging device 1, The set 3A and the charging device 1 are connected. The battery mounting portion 7 and the terminal 70 are examples of the “battery connecting portion” in the present invention.

  The protection IC 3C individually monitors the voltage of each of the four battery cells 3a, and even if one of the cells is not in a normal state, for example, when an overcharge state or an overdischarge state occurs, an abnormal signal is output to the battery. Output to the side control unit 3G. The battery side power supply circuit 3D is a circuit that transforms the voltage of the battery group 3A and supplies the power to the battery side control unit 3G.

  The battery temperature detection circuit 3E is a circuit that detects the temperature of the battery set 3A (battery temperature), and includes a temperature sensitive element such as a thermistor (not shown) provided adjacent to the battery set 3A. The battery temperature detection circuit 3E detects the battery temperature using a temperature sensitive element such as a thermistor, converts the detected temperature into a voltage signal, and outputs the voltage signal to the battery side control unit 3G.

  The first blocking element 3F is, for example, a thermal protector, a fuse or the like provided between the positive connection terminal 3b and the battery group 3A for protecting the battery group 3A (battery cell 3a). The first cutoff element 3F has a cutoff characteristic that defines a condition for cutting off the charging current. If the first cutoff element 3F satisfies the cutoff characteristic, the first cutoff element 3F allows the charging current to flow through the battery group 3A (battery cell 3a). The charging current is cut off when the cutoff characteristic is not satisfied. More specifically, the first interruption element 3F has a first interruption characteristic curve A (charging current-ambient temperature curve) shown in FIG. The first blocking element 3F is an example of the "blocking means" in the present invention.

  FIG. 10 is a diagram showing a first cutoff characteristic curve A of the first cutoff element 3F. The first cutoff characteristic curve A is a curve showing a boundary between a state in which the first cutoff element 3F is in the open state and cuts off the charging current, and a state in which the first cutoff element 3F is in the closed state and allows the charge current, and FIG. In the graph above, the region above the first cutoff characteristic curve A is a region where the first cutoff element 3F is in the open state and cuts off the charging current, that is, a region where the cutoff characteristic is not satisfied. The ambient temperatures Ta to Te and T1 to T6 shown in FIG. 10 satisfy T1<Ta<T2<Tb<T3<Tc<T4<Td<T5<Te<T6, and the charging currents I1 to T6 are satisfied. I5 satisfies I5<I4<I3<I2<I1.

  The first cutoff characteristic curve A of the first cutoff element 3F shows that the higher the charging current, the lower the maximum allowable ambient temperature (the maximum allowable temperature), in other words, the higher the ambient temperature, the higher the allowable value. The maximum value of charging current (maximum allowable current value) is set to be small.

  For example, when the charging current is I4, the maximum allowable temperature is Td, the charging current is allowed to flow until the ambient temperature reaches Td, and the charging current is cut off when the ambient temperature becomes Td or higher. In other words, when the charging current is I4, the maximum allowable temperature is Td, the cutoff characteristic is satisfied until the ambient temperature reaches Td, and the cutoff characteristic is not satisfied when the ambient temperature is Td or higher. Become. The case where the cutoff characteristic in the present embodiment is satisfied is an example of the “case where the predetermined condition is satisfied” in the present invention.

  On the other hand, when the charging current is I3 which is larger than I4, the maximum allowable temperature is Tc lower than Td when the charging current is I4, and when the ambient temperature is Tc or higher, the charging current is cut off. From another viewpoint, when the ambient temperature is Tc, the maximum allowable current value is I3, and when the charging current is I3 or more, the charging current is cut off. On the other hand, when the ambient temperature becomes Td higher than Tc, the maximum allowable current value becomes I4 which is smaller than I3.

  Note that T6 is the ambient temperature at which the first cutoff element 3F is in the open state even when the charging current is not flowing. In the present embodiment, the first blocking element 3F is installed in contact with the battery group 3A, and the ambient temperature is substantially the same as the battery temperature. Therefore, the first blocking element 3F not only plays a role of limiting or blocking the charging current, but also plays a role of preventing charging from being started when the battery temperature is higher than a predetermined value.

  The battery side control unit 3G is a microcomputer having a ROM, a RAM, an arithmetic function, etc., and has an information communication port 3H. The information communication port 3H is connected to a predetermined terminal of the plurality of terminals 70 of the charging device 1 when the battery pack 3 is connected to the charging device 1. Communication between the battery side control unit 3G and the charging device 1 is performed via the information communication port 3H.

  The battery-side control unit 3G transmits the battery type from the information communication port 3H to the charging device 1 during charging. The battery type is classified according to the characteristics of the battery pack 3, and the charging device 1 can specify the characteristics of the battery pack 3 required for charging control by receiving the battery type from the battery side control unit 3G. .. The characteristics of the battery pack 3 that can be specified from the battery type include, for example, the number of battery cells 3a forming the battery group 3A, the connection configuration (the number of series, the number of parallel), the maximum charging voltage of the battery cells 3a, and the battery group 3A The nominal capacity of the battery pack 3, the cutoff characteristic of the first cutoff element 3F of the battery pack 3 (first cutoff characteristic curve A), the target charging voltage for properly charging the entire battery group 3A (the maximum charging voltage in the present embodiment). The same), the allowable charging current value, the termination current value which is a criterion for terminating charging, and the like. In the present embodiment, the battery type of the battery pack 3 is C, for example. When the abnormal signal is input from the protection IC 3C, the battery-side control unit 3G outputs a charge stop signal to the charging device 1 via the information communication port 3H.

  Next, a battery pack 33 having a different battery type from the battery pack 3 will be described. The battery pack 33 includes a battery set 33A having different characteristics from the battery set 3A. The battery group 33A has the same nominal capacity (6Ah) as the battery group 3A, but the allowable charging current value is different, for example, 12A (2C) or more. Since the allowable charging current value varies depending on the manufacturer and performance of the battery cell, it is not limited to this current value. The battery pack 33 includes the battery set 33A having an allowable charging current value different from that of the battery set 3A, and thus includes the second blocking element 33F having a blocking characteristic different from that of the first blocking element 3F. More specifically, the second cutoff element 33F has the second cutoff characteristic curve B shown in FIG. In addition, in the present embodiment, the battery type of the battery pack 33 is, for example, D, and when the battery pack 33 is attached, the charging device 1 uses the battery side control unit 3G of the battery pack 33 as the battery type D By receiving, it is possible to specify the cutoff characteristic of the second cutoff element 33F of the battery pack 33, that is, the second cutoff characteristic curve B, the target charging voltage, and the like. The second blocking element 33F is an example of the "blocking means" in the present invention.

  FIG. 11 is a diagram showing a second cutoff characteristic curve B of the second cutoff element 33F. The ambient temperatures T1 to T5 and the charging currents I1 to I5 shown in FIG. 11 are the same values as the ambient temperatures T1 to T5 and the charging currents I1 to I5 shown in FIG. , T6 and Tf to j satisfy T5<Tf<Tg<Th<Ti<Tj<T6.

  As shown in FIG. 11, the second cutoff characteristic curve B of the second cutoff element 33F has a lower maximum allowable temperature as the charging current increases, similar to the first cutoff characteristic curve A of FIG. There is. In the second cutoff element 33F (second cutoff characteristic curve B), the maximum allowable temperatures corresponding to the charging currents I1 to I5 are Tf to Tj, respectively, and the minimum allowable maximum temperature of Tf to Tj is Tf. Even if there is, it is higher than the allowable maximum temperatures Ta to Te corresponding to the charging currents I1 to I5 in T5 and the first blocking element 3F (first blocking characteristic curve A).

  In the present embodiment, the battery temperature is substantially the same as the ambient temperature as described above, and generally the battery temperature tends to increase as the charging current increases and as the charging current flows longer. .. In view of the above, the battery pack 33 including the second blocking element 33F having an allowable maximum temperature higher than that of the first blocking element 3F of the battery pack 3 flows a larger charging current for a longer time than the battery pack 3. be able to. For example, comparing the case where the battery pack 3 and the battery pack 33 are charged with the charging current I1, the battery temperature (ambient temperature) in the battery pack 3 is allowed only up to Ta (<Tf), but in the battery pack 33, Tf. (>Ta) is allowed. Therefore, when the ambient temperature Ta is reached, the charging current (I1) is cut off in the battery pack 3 but not in the battery pack 33, and the charging current can be continued thereafter. In this way, the battery pack 33 can flow the charging current I1 for a longer time than the battery pack 3.

  Next, the electrical configuration of the charging device 1 will be described. As shown in FIG. 9, the charging device 1 includes a power supply circuit 48, an auxiliary power supply circuit 53, a switching power supply circuit 54, a charging control unit 45, a voltage setting control circuit 55, and a current setting circuit 56. A current control circuit 57, a first control signal transmission unit 61, a second control signal transmission unit 62, a fan unit 58, a temperature detection element 44, a voltage detection circuit 59, and a display circuit 60. With the battery pack 3 attached, the battery set 3A (battery cells 3a) of the battery pack 3 is charged by constant current/constant voltage control.

  The constant current/constant voltage control is to set a target current value when charging is started, and charge while controlling the charging current so that the charging current becomes the target current value (constant current control). After the voltage reaches the predetermined target charging voltage, charging is continued while maintaining the charging voltage at the target charging voltage (constant voltage control), and the charging current becomes equal to or less than the predetermined end current value under constant voltage control. In this case, the charging control ends the charging.

  The power supply circuit 48 is a circuit that supplies power to the battery pack 3, and includes a first rectifying and smoothing circuit 50, a switching circuit 51, a charge plus line 48A, a charge minus line 48B, and a second rectifying and smoothing circuit 52. Is equipped with.

  The first rectifying/smoothing circuit 50 includes a full-wave rectifying circuit 50A and a smoothing capacitor 50B. The full-wave rectifying circuit 50A full-wave rectifies the AC voltage supplied from the commercial AC power source P, and the smoothing capacitor 50B. And output DC voltage after smoothing. The commercial AC power supply P is, for example, an AC100V external power supply.

  The switching circuit 51 is connected to the first rectifying/smoothing circuit 50, and includes a transformer 42, a FET 43, and a PWM control IC 51A. The PWM control IC 51A changes the drive pulse width of the FET 43, the FET 43 performs switching according to the drive pulse width, and sets the DC output from the first rectifying and smoothing circuit 50 as the voltage of the pulse train waveform. The voltage of the pulse train waveform is applied to the primary winding of the transformer 42, stepped down (or stepped up) by the transformer 42, and output to the second rectifying and smoothing circuit 52.

  The second rectifying/smoothing circuit 52 includes two diodes 41, a smoothing capacitor 52A, and a discharging resistor 52B. The output voltage obtained from the secondary winding of the transformer 42 is rectified and smoothed to output a DC voltage. The DC voltage is configured to be output from a predetermined terminal (a plurality of terminals 70) connected to each of the positive connection terminal 3b and the negative connection terminal 3c of the battery pack 3.

  The charging plus line 48A and the charging minus line 48B are electric paths through which a charging current flows when the battery pack 3 is charged. The charging plus line 48A connects the terminal 70 connected to the plus connection terminal 3b and one end of the secondary winding of the transformer 42 with the battery pack 3 connected to the battery mounting portion 7. The charging minus line 48B connects the terminal 70 connected to the minus connection terminal 3c and the other end of the secondary winding of the transformer 42 with the battery pack 3 connected to the battery mounting portion 7. A current detection resistor 48C is provided on the charging minus line 48B.

  The current detection resistor 48C is a shunt resistor for detecting the charging current flowing in the battery pack 3, and is provided between the second rectifying and smoothing circuit 52 and GND on the charging minus line 48B. The charging current is detected by inverting and amplifying the voltage drop of the current detection resistor 48C by the current control circuit 57 and inputting it to the charging control unit 45.

  The auxiliary power supply circuit 53 is a constant voltage power supply circuit for supplying a stabilized reference voltage Vcc to various circuits such as the charge control unit 45 and operational amplifiers 55E and 57A described later. The auxiliary power supply circuit 53 is connected to the first rectifying/smoothing circuit 50, and has coils 53a, 53b and 53c, a switching element 53A, a control element 53B, a rectifying diode 53C, a three-terminal regulator 53D, and an oscillation preventing circuit. It is provided with capacitors 53E and 53F and a reset IC 53G. The reset IC 53G is an IC that outputs a reset signal to the charging control unit 45 and resets the charging control unit 45.

  The switching power supply circuit 54 is a circuit that supplies power to the PWM control IC 51A, and includes a coil 54a, a rectifying diode 54b, and a smoothing capacitor 54c.

  The charge control unit 45 is a microcomputer including a ROM, a RAM, and a calculation unit, and has an A/D input port unit 45A, a first output port unit 45B, a second output port unit 45C, and a digital communication port unit 45D. , And a reset port section 45E. The charge control unit 45 processes various signals input to the A/D input port unit 45A and the digital communication port unit 45D by the arithmetic unit, and outputs various signals based on the processing result to the first output port unit 45B and the second output. Output from the port unit 45C and the digital communication port unit 45D to the current setting circuit 56, the fan unit 58, etc. to control the charging of the battery pack that is the charging target.

  The ROM includes various control programs required for charge control, battery types of a plurality of types of rechargeable battery packs, characteristics corresponding to the battery types (the above-described cutoff characteristics, target charging voltage, etc.), and FIG. The stored table is stored. The charge control unit 45 receives the battery type from the battery pack connected to the terminal 70, and specifies the characteristics of the connected battery pack from the received battery type.

  The A/D input port section 45A is connected to the current control circuit 57, the temperature detection element 44, and the voltage detection circuit 59. The A/D input port unit 45A has a voltage signal indicating the charging current from the current control circuit 57, a voltage signal indicating the temperature of the charging circuit unit 4 from the temperature detecting element 44, and a voltage indicating the charging voltage from the voltage detecting circuit 59. A signal is input.

  The first output port unit 45B has a plurality of ports, and each of the plurality of ports is connected to the current setting circuit 56 or the fan unit 58. The charging control unit 45 sends a signal for setting the target current value from the first output port unit 45B to the current setting circuit 56, and a fan control signal for controlling the first fan 5 and the second fan 6 to the fan unit 58. Output to.

  The second output port unit 45C has a plurality of ports, and each of the plurality of ports is connected to the display circuit 60 or the second control signal transmission unit 62. The charging control unit 45 outputs a signal for controlling the display circuit from the second output port unit 45C to the display circuit 60 and a signal for controlling the start/stop of charging to the second control signal transmission unit 62.

  The digital communication port unit 45D is connected to the information communication port 3H of the battery pack 3 when the battery pack 3 is connected to the battery mounting unit 7, and is configured to be capable of bidirectional communication. The charge control unit 45 acquires information on the battery pack 3 necessary for charge control, that is, the battery temperature and the battery type, via the digital communication port unit 45D. The reset port unit 45E is connected to the auxiliary power supply circuit 53 and receives the reset signal output from the reset IC 53G. The digital communication port unit 45D is an example of the "battery temperature acquisition means" in the present invention.

  The voltage setting control circuit 55 is a circuit that sets a target charging voltage and controls the charging voltage to be the target charging voltage. The voltage setting control circuit 55 includes voltage dividing resistors 55A to 55D, an operational amplifier 55E, and a diode 55F.

  The voltage dividing resistors 55A and 55B are connected in series between the charging plus line 48A and GND, and the connection point of the voltage dividing resistors 55A and 55B is connected to the inverting input terminal of the operational amplifier 55E. The charge voltage appearing on the charge plus line 48A is divided by the voltage dividing resistors 55A and 55B, and the divided voltage value is output to the inverting input terminal of the operational amplifier 55E as a comparison voltage value.

  The voltage dividing resistors 55C and 55D are connected in series between the reference voltage Vcc and GND, and the connection point of the voltage dividing resistors 55C and 55D is connected to the non-inverting input terminal of the operational amplifier 55E. The reference voltage Vcc is divided by the voltage dividing resistors 55C and 55D, and the divided voltage value is output to the non-inverting input terminal of the operational amplifier 55E as a reference value for setting the target charging voltage.

  The operational amplifier 55E is an element that compares the above-described comparison voltage value with a reference value, and its output terminal is connected to the first control signal transmission unit 61 via the diode 55F.

  The current setting circuit 56 is a circuit that selectively sets a target current value, and includes voltage dividing resistors 56A to 56F. The voltage dividing resistors 56A and 56B are connected in series between the reference voltage Vcc and GND, and the voltage dividing resistors 56C to 56F are the connection points 56a of the voltage dividing resistors 56A and 56B and the first of the charging control unit 45. It is connected in parallel with the output port section 45B. Further, the connection point 56a is connected to the current control circuit 57, and the voltage (divided value) appearing at the connection point 56a is output to the current control circuit 57 as a reference value for setting the target current value. In the present embodiment, the target current value is selectively selected from the five current values I1 to I5 by outputting or not outputting the low signal from the first output port unit 45B to the voltage dividing resistors 56C to 56F. Can be set to. The current setting circuit 56 is an example of the "current setting means" in the present invention.

  Specifically, a low signal is not output from any port of the first output port unit 45B, and the divided voltage value that appears at the connection point 56a when the reference voltage Vcc is divided by the voltage dividing resistors 56A and 56B is the target value. It serves as a reference value when the current value is set to I1. In the present embodiment, I1 is 12 A, for example.

  When a low signal is output from the port connected to the voltage dividing resistor 56C of the first output port unit 45B and the reference voltage Vcc is divided by the parallel resistance of the voltage dividing resistors 56B and 56C and the voltage dividing resistor 56A. The divided voltage value appearing at the connection point 56a of is a reference value when the target current value is set to I2. In the present embodiment, I2 is 10 A, for example.

  Similarly, the voltage division value that appears at the connection point 56a when a low signal is output from the port connected to the voltage dividing resistor 56D of the first output port unit 45B is the reference value when the target current value is set to I3. Therefore, the voltage division value that appears at the connection point 56a when a low signal is output from the port connected to the voltage division resistor 56E of the first output port unit 45B becomes the reference value when the target current value is set to I4. , The divided voltage value that appears at the connection point 56a when a low signal is output from the port connected to the voltage dividing resistor 56F of the first output port unit 45B becomes the reference value when the target current value is set to I5. .. In the present embodiment, for example, I3 is 9A, I4 is 8A, and I5 is 6A.

  The target current values I1 to I5 may be set to different values depending on the battery type (nominal voltage, number of cells, etc.) of the battery pack 3. In other words, if the type of battery pack (battery type) is different, the combination of I1, I2, I3, I4, and I5 may be different. Further, a low signal may be simultaneously output from two or more ports of the four ports of the first output port unit 45B connected to the voltage dividing resistors 56C to 56F. In this case, the target current value It is possible to set 6 or more types.

  The current control circuit 57 includes operational amplifiers 57A and 57B, resistors 57C to 57G, and a diode 57H. The output terminal of the operational amplifier 57A is connected to the A/D input port unit 45A of the charge control unit 45, the inverting input terminal is connected to the current detection resistor 48C via the resistor 57C, and the non-inverting input terminal is connected to GND. Has been done. The output terminal of the operational amplifier 57B is connected to the first control signal transmission unit 61 via the resistor 57G and the diode 57H, the inverting input terminal is connected to the output terminal of the operational amplifier 57A via the resistor 57E, and the non-inverting input terminal is , The connection point 56a of the current setting circuit 56.

  The current control circuit 57 inverts and amplifies the comparison voltage corresponding to the charging current input to the inverting input terminal of the operational amplifier 57A by the operational amplifier 57A and inputs the same to the inverting input terminal of the operational amplifier 57B, and the comparison voltage and current setting circuit. The charging current is controlled by comparing a reference value corresponding to the target current value input from the non-inverting input terminal of the operational amplifier 57B from 56 and outputting a voltage signal according to the comparison result from the output terminal of the operational amplifier 57B. .. The current control circuit 57 is an example of the “current control means” in the present invention. The charge control unit 45, the current setting circuit 56, and the current control circuit 57 are examples of the “charge control means” in the present invention.

  The first control signal transmission unit 61 includes a photo coupler 61A. The photocoupler 61A is connected to the voltage setting control circuit 55 and the current control circuit 57, and responds to a signal output from the output terminal of the operational amplifier 55E of the voltage setting control circuit 55 and the output terminal of the operational amplifier 57B of the current control circuit 57. And outputs a feedback signal to the PWM control IC 51A.

  The fan unit 58 includes a first fan 5, a second fan 6, a constant voltage circuit 58A, a first fan control circuit 5A, and a second fan control circuit 6A. The constant voltage circuit 58A is a circuit that converts the output voltage of the second rectifying and smoothing circuit 52 and supplies it to the first fan 5 and the second fan 6. The first fan control circuit 5A and the second fan control circuit 6A are connected to the first output port unit 45B of the charging control unit 45. According to the fan control signal output from the first output port unit 45B, the first fan control circuit 5A controls driving/stopping of the first fan 5 and the air volume, and the second fan control circuit 6A controls the second fan. 6 drive/stop and air volume control.

  The temperature detection element 44 is connected to the A/D input port unit 45A of the charging control unit 45, detects the temperature inside the case 2, that is, the temperature of the charging circuit unit 4, and outputs a voltage indicating the detected temperature. The signal is output to the A/D input port unit 45A.

  The voltage detection circuit 59 is a circuit that detects a charging voltage and includes voltage dividing resistors 59A and 59B. The voltage dividing resistors 59A and 59B are connected in series between the charging plus line 48A and GND of the charging device 1, and the connection point of the voltage dividing resistors 59A and 59B is the A/D input port of the charging control unit 45. It is connected to the section 45A. The charging voltage appearing on the charging plus line 48A is divided by the voltage dividing resistors 59A and 59B, and the divided voltage value is input to the A/D input port unit 45A of the charging control unit 45 as a voltage signal indicating the charging voltage. The charging control unit 45 detects the charging voltage by reading the voltage signal.

  The display circuit 60 is a circuit for displaying the charging state, and includes an LED 60A and resistors 60B and 60C. The LED 60A is connected to the second output port unit 45C of the charging control unit 45 via the resistors 60B and 60C. When the charging control unit 45 outputs a high signal from the port connected to the resistor 60B of the second output port unit 45C, the LED 60A lights up in red and the port connected to the resistor 60C of the second output port unit 45C. When a high signal is output from the LED 60A, the LED 60A lights up in green, and when a high signal is output from both the port connected to the resistor 60B and the port connected to the resistor 60C of the second output port unit 45C. Causes the LED 60A to light orange. In the present embodiment, the charging control unit 45 turns on the LED 60A in red in a state before charging, such as when the battery pack 3 is not connected or in a charging standby state, and turns on the LED 60A in orange during charging to charge the battery. After the end, the green color of the LED 60A is turned on.

  The second control signal transmission unit 62 includes a photo coupler 62A and a FET 62B. The photocoupler 62A transmits a signal for controlling start/stop to the PWM control IC 51A. The FET 62B is connected between the light emitting element forming the photocoupler 62A and the GND, and the gate of the FET 62B is connected to the second output port unit 45C. When a high signal is output from the port connected to the FET 62B of the second output port unit 45C of the charging control unit 45, the FET 62B turns on and the photocoupler 62A turns on. As a result, the PWM control IC 51A is activated and charging is started. When a low signal is output from the port of the second output port unit 45C connected to the FET 62B, the FET 62B turns off and the photocoupler 62A turns off. As a result, the PWM control IC 51A is stopped, and the charging is stopped (ended).

  Next, charging control by the charging control unit 45 of the charging device 1 will be described. The charging control unit 45 of the charging device 1 according to the present embodiment performs charging control for the purpose of shortening the charging time, in particular, charging a battery pack of high capacity (nominal capacity of 5 Ah or more) at 2 C or more. The charging time is controlled by performing so-called 2C charging, which is charging with an electric current.

  In the conventional charging device, when a high-capacity battery pack is attempted to be charged with a relatively large charging current (charging current of 2C or more) with respect to the nominal capacity in order to shorten the charging time, it is a target for charging. Since the blocking element of the battery pack operates in a short time and charging is interrupted, there is a problem that the charging time becomes long as a result.

  In view of the above problems, in the present embodiment, a charging current of 2C or more with respect to the nominal capacity (5Ah or more) of the battery pack (10A or more when the nominal capacity is 5Ah, 12A or more when the nominal capacity is 6Ah, that is, 10A). The charging is started in the above manner, and in consideration of the breaking characteristics (breaking characteristic curve) of the breaking element included in the battery pack, the range in which the breaking element does not operate (the range satisfying the breaking characteristics, the breaking characteristic curves of FIGS. 10 and 11 In a region below), control is performed such that the target current value is sequentially changed so that charging is performed with the largest possible charging current. Further, in addition to the above control, even if charging is started with a charging current of 2C or more with respect to the nominal capacity of a high-capacity battery pack and a charging current of 2C or more is flown, the shutoff element of the battery pack to be charged Does not operate, charging is performed with a charging current of 2C or more from the start of charging until the charging voltage reaches the target charging voltage, and control is performed to shorten the charging time. The charging current is more preferably 2 C or more and 3 C or less (or 10 A or more and 15 A or less) in consideration of the balance between the shortening of the charging time and the deterioration and failure of the battery pack due to the charging current. However, the upper limit is not limited to 3C or less, and may be 3C (15A) or more because it depends on the manufacturer and performance of the battery cell. Further, the charging device 1 can charge a battery pack of 5 Ah or more with a charging current of 2 C (10 A) or more, and can charge a battery pack of less than 5 Ah with a charging current of 2 C or more. Therefore, the conventional battery pack can also shorten the charging time. Further, the charging device 1 can charge not only battery packs in which four cells are connected in series but also battery packs having different voltages (5 cells or more and 3 cells or less in series). In this case, the voltage setting control circuit 55 may be configured to be able to set a plurality of target charging voltages so as to correspond to battery packs having different voltages.

  Next, an example of the charging process by the charging device 1 will be described with reference to FIGS. 12 to 14. 12 and 13 are flowcharts showing the charging process by the charging control unit 45 of the charging device 1. FIG. 14 is a table for determining the target current value used when the charge control unit 45 charges the battery pack 3.

  When the charging device 1 is connected to the commercial AC power source P, as shown in FIG. 12, the charging control unit 45 starts the charging control in S1, and the charging standby state is shown in S2. The display circuit 60 is illuminated in red. To turn on the display circuit 60 in red, a high signal is output from the port connected to the resistor 60B among the plurality of ports of the second output port unit 45C, and the LED 60A is turned on in red.

  After the LED 60A is turned on in red in S2, it is determined in S3 whether or not the battery pack is mounted in the battery mounting portion 7 (terminal 70). Whether or not the battery pack is attached is determined by the battery side control unit 3G of the battery pack and the charging control unit 45 communicating with each other via the information communication port 3H and the digital communication port unit 45D. When the battery pack is not attached (S3: No), the process returns to S2. That is, the charging standby state is maintained by repeating S2 and S3 until the battery pack is mounted.

  When it is determined in S3 that the battery pack is mounted in the battery mounting portion 7 (S3: Yes), the battery type is determined in S4. The battery type is determined by communication with the battery pack. In the present embodiment, when the battery pack 3 is mounted in the battery mounting portion 7 (terminal 70), the charging control unit 45 receives C as the battery type, and when the battery pack 33 is mounted, Receive D as a seed. In the present embodiment, the battery type is discriminated by communication with the battery pack.However, if the battery pack is provided with a discrimination resistor for discriminating the battery type, the charging device is connected to the discrimination resistor. A configuration may be adopted in which a possible discrimination terminal is provided and the battery type is discriminated by reading the resistance value of the discrimination resistance.

  After determining the battery type in S4, the target current value is set to I1 in S5, and in S6, charging is started at a charging current of 2C or more, that is, I1. The charging is started by outputting a high signal from the port connected to the FET 62B of the second control signal transmission unit 62 among the plurality of ports of the second output port unit 45C to activate the PWM control IC 51A. ..

  When charging is started in S6, the display circuit 60 is lit in orange to indicate that charging is in progress in S7. In order to light the display circuit 60 in orange, a high signal is output from both of the ports connected to the resistor 60B and the port connected to the resistor 60C among the plurality of ports of the second output port unit 45C. , LED 60A is lit in orange.

  In addition, the display circuit 60 is lit in orange in S7, and the first and second fans 5 and 6 are driven in S8. The driving of the first and second fans 5 and 6 is performed by outputting a fan control signal from the first output port unit 45B to the first fan control circuit 5A and the second fan control circuit 5B. The first and second fans 5 and 6 generate the first and second cooling air, and the air is taken into the case 2 through the intake port 24a. As a result, a cooling air passage of the charging device 1 toward the first and second exhaust ports 22a and 23a is formed. Further, a cooling air passage for the battery pack extending from the opening 71 toward the first and second exhaust ports 22a and 23a is also formed.

  After driving the first and second fans 5 and 6, it is determined in S9 whether or not the battery type is C. When the battery type is C (S9: Yes), it is determined that the battery pack 3 is connected to the charging device 1, and in S10, the target current value according to the battery temperature (ambient temperature) is shown in FIG. Reconfigure (change) according to the table shown. The battery temperature is detected by communication with the battery pack 3 similarly to the battery type determination.

  The table shown in FIG. 14 shows that the first cutoff element 3F is charged in the range in which the first cutoff element 3F does not operate (the range in which the charge current is not cut off, and the range in which the cutoff characteristic is satisfied), in order to charge the charge current as large as possible. It is a correspondence table of the battery temperature and the target current value, which is determined in consideration of the breaking characteristic of the element 3F, that is, the first breaking characteristic curve A.

  As shown in FIG. 14, when the battery temperature (ambient temperature) is lower than T1, the target current value is reset (changed) to I1. As shown in FIG. 10, T1 is a value slightly lower than the maximum allowable temperature Ta corresponding to the charging current I1 in the first cutoff characteristic curve A. When the battery temperature is T1 or higher and lower than T2, the target current value is changed to I2. T2 is a temperature between the maximum allowable temperature Ta corresponding to the charging current I1 and the maximum allowable temperature Tb corresponding to the charging current I2 in the first cutoff characteristic curve A (Ta<T2<Tb), which is smaller than Tb. It is a low value.

  According to the first cutoff characteristic curve A, I1 which is the maximum current value of the target current values that can be set by the charging device 1 can be set as the target current value until the battery temperature reaches Ta. When the battery temperature slightly rises above T1 and reaches Ta while the charging current I1 is flowing, the first cutoff element 3F is opened and the charging current is cut off to interrupt the charging. The target current value is changed to I2 which is lower than I1 when T1 which is slightly lower than Ta is reached. As a result, it is possible to reliably prevent the first blocking element 3F from blocking the charging current.

  Further, as shown in FIG. 14, when the battery temperature is T2 or higher and lower than T3, the target current value is set to I3, and when T3 or higher and lower than T4, the target current value is set to I4 and T4 or higher. In the case of, the target current value is set to I5. Due to the same purpose as the above-described T1 and T2, T3 is determined to satisfy Tb<T3<Tc, T4 is determined to satisfy Tc<T4<Td, and T5 is determined to be Td< It is determined to satisfy T5<Te. T1 to T5 are set as described above, and the target current value (charging current) is sequentially changed to a smaller value at a temperature slightly lower than the maximum allowable temperature corresponding to the currently set target current value (charging current). By doing so, it is possible to charge with as large a charging current as possible in a range in which the first blocking element 3F does not operate, and it is possible to reliably avoid the opening state of the first blocking element 3F and continue charging. You can As a result, the charging time of a high capacity battery pack can be shortened. Note that I1 is an example of the "first current value" in the present invention. When I1 is the "first current value", I2 is an example of the "second current value" in the present invention, and I3 is an example of the "third current value" in the present invention. Further, T1 is an example of the "first temperature threshold value" in the present invention. When T1 is the “first temperature threshold”, T2 is an example of the “second temperature threshold” in the present invention, Ta is an example of the “first battery temperature” in the present invention, and Tb is the present It is an example of the "2nd battery temperature" in an invention.

  Returning to FIG. 12, after the target current value is reset (changed) in S10 as described above, it is determined in S11 whether the full charge has been reached. The determination of full charge is made, for example, when the charge current falls below a predetermined final current value under constant voltage control in a general constant current constant voltage control as a method of charging a lithium ion battery, it is determined as full charge. do it. However, the method of determining full charge is not limited to this.

  When it is determined that the battery is fully charged (S11: Yes), the charging is ended in S13. The process of stopping charging is performed by outputting a low signal from the port connected to the FET 62B among the plurality of ports of the second output port unit 45C and stopping the PWM control IC 51A.

  On the other hand, when it is determined that the battery is not fully charged (S11: No), it is determined in S12 whether the battery temperature is T5 or higher. It is assumed that T5 is a high temperature that does not normally reach in the state of charging with the charging current I5 and is not suitable for charging to the battery group 3A, and when the battery temperature reaches T5 or higher, charging is performed. In S13, the process of stopping the charging is performed to stop the charging.

  When it is determined in S12 that the battery temperature is not equal to or higher than T5, the process returns to S10, and the target current value according to the battery temperature is changed again. That is, the target for which the battery temperature is set is repeated by repeating S9, S10, S11, and S12 until it is determined that the battery is fully charged in S11 or the battery temperature is T5 or higher in S12. Each time the temperature reaches a temperature slightly lower than the maximum allowable temperature corresponding to the current value, the battery pack 3 is charged by the constant current/constant voltage control while the target current value is gradually changed to a lower current value. Even when the battery temperature drops, the target current value is changed according to the battery temperature after the drop. For example, when the battery temperature drops from the range of T3 or higher and lower than T4 to the range of T2 or higher and lower than T3, the target current value is changed from I4 to I3 which is higher than I4.

  Returning to S9, when it is determined that the battery type is not C, that is, the battery type is D (S9: No), it is determined that the battery pack 33 is attached to the charging device 1, and the processing of S11 and S12 is performed. move on. That is, the process of changing the target current value in consideration of the breaking characteristic in S10 is not performed. This is because in the second cutoff element 33F included in the battery pack 33, as shown in FIG. 11, when the battery temperature is in the range of Tf or lower, the target current values I1 to I5 that the charging device 1 can set. In any of the above cases, the charging current is not interrupted, and within the range in which the second interruption element 33F does not operate, from the start of charging until the charging voltage reaches the target charging voltage, the maximum of the settable target current values is reached. This is because charging can be performed with the current value I1 and it is not necessary to change the target current value.

  The second cutoff element 33F of the battery pack 33 does not cut off the charging current in the range of Tf or less, but in order to suppress deterioration and failure of the battery pack 33, the second cutoff element 33F is set to T5 or higher, which is lower than Tf. If it does (S12: Yes), charging is terminated. As described above, when the battery pack 33 is attached to the charging device 1, the charging voltage of 2C, that is, the charging voltage from the start of charging at the charging current of 2C, i.e. It is charged until the target charging voltage is reached.

  After the process of ending charging is performed in S13, as shown in FIG. 13, the display circuit 60 is turned on in green in S14 to indicate that the charging is completed. To turn on the display circuit 60 in green, a high signal is output from the port connected to the resistor 60C among the plurality of ports of the second output port section 45C, and the LED 60A is turned on in green.

  After turning on the display circuit 60 in green in S14, it is determined in S15 whether the battery temperature is 40 degrees or higher. If the battery temperature is 40 degrees or higher (S15: Yes), S15 is repeated while continuing to drive the first and second fans, and cooling of the battery pack 3 is continued until the battery temperature becomes lower than 40 degrees.

  When the battery temperature is lower than 40 degrees (S15: No), it is determined in S16 whether the temperature of the charging circuit unit 4 is 40 degrees or higher. The temperature of the charging circuit unit 4 is detected by reading a voltage signal indicating the temperature of the charging circuit unit 4 output from the temperature detecting element 44 to the A/D input port unit 45A. If the temperature of the charging circuit unit 4 is 40 degrees or more (S16: Yes), the process returns to S15, and while repeating S15 and S16, the temperature of the charging circuit unit 4 becomes less than 40 degrees, and The driving is continued to continue cooling the charging circuit unit 4. When the temperature of the charging circuit unit 4 becomes lower than 40 degrees (S16: No), the driving of the first and second fans 5 and 6 is stopped in S17.

  When the battery pack 3 or 33 is being charged in S6 to S13, an air passage extending from the intake port 24a to the first and second exhaust ports 22a and 23a is formed in the case 2. Since the diode 41, the transformer 42, and the FET 43 are arranged in the vicinity of the intake port 24a, the unheated air immediately after being sucked in from the intake port 24a is cooled as cooling air, so that it is efficiently cooled.

  Further, since the heat dissipation members 46 and 47 define the air passage so that the diode 41, the transformer 42, and the FET 43 are included in the air passage, the diode 41, the transformer 42, and the FET 43 that need cooling can be efficiently cooled. Further, since the diode 41 and the FET 43 are attached to the heat dissipation members 46 and 47, respectively, the diode 41 and the FET 43 are exposed to the cooling air flowing along the heat dissipation members 46 and 47 and are efficiently cooled. Furthermore, since the transformer 42 is located on the most upstream side of the air passage defined by the heat radiating members 46 and 47 (in the vicinity of the intake port 24a), it is efficiently cooled by the air before being heated.

  Returning to the description of the charging process, after stopping the driving of the first and second fans 5 and 6 in S17, it is determined in S18 whether or not the battery pack is detached from the charging device 1. When it is determined that the battery pack is not detached (S18: No), the charging end state is maintained until the battery pack is detached from the charging device 1 while repeating S18. On the other hand, when it is determined that the battery pack has been detached (S18: Yes), the process returns to S2, and the charging standby state is maintained until the battery pack is attached to the charging device 1 again. As described above, according to the charging device 1 of the present embodiment, the high capacity (5 Ah or more) battery pack 3 or 33 can be directly charged from the commercial AC power source P with a large current (2 C or more or 10 A or more). Therefore, the charging time can be shortened.

  Next, with reference to FIGS. 15(a) and 15(b), a time change of the battery temperature, the charging voltage, and the charging current of the battery packs 3 and 33 when the above charging process is performed will be described. FIGS. 15A and 15B are time charts showing time changes of the battery temperature, the charging voltage, and the charging current when the charging control by the charging device 1 is performed.

  As shown in FIG. 15A, when the battery pack 3 is charged by the charging device 1 according to the present embodiment, at time t0, the target current value is set to I1 (this embodiment by the charge control unit 45). 12A), that is, a charging current of 2C is set for the nominal capacity 6Ah of the battery pack 3 (corresponding to S5), and charging is started with the charging current I1 (corresponding to S6). When charging is started, the battery pack 3 is charged by constant current control while the charging current is maintained at I1 (corresponding to repetition of S9, S10, S11 and S12). After time t0, the battery temperature and the charging voltage increase with charging, and the battery temperature reaches T1 at time t1.

  When the battery temperature reaches T1 at time t1, the target current value is changed (reset) from I1 to I2 by the charging control unit 45, and the charging current drops from I1 to I2 (corresponding to S10). After the charging current drops to I2, the charging is continued by the constant current control while maintaining the charging current at I2 (corresponding to the repetition of S9, S10, S11 and S12). At time t1, the charging voltage drops once as the charging current drops, but after time t1 it rises again as the charging continues. The battery temperature rises after time t1 and reaches T2 at time t2.

  When the battery temperature reaches T2 at time t2, the target current value is changed (reset) from I2 to I3 by the charging control unit 45, and the charging current drops from I2 to I3 (corresponding to S10). After the charging current drops to I3, the charging is continued by the constant current control with the charging current maintained at I3 (corresponding to the repetition of S9, S10, S11 and S12). At time t2, the charging voltage drops again as the charging current drops, but after time t2, the charging voltage further rises as the charging continues. Further, the battery temperature further rises after time t2 and reaches T3 at time t3.

  When the battery temperature reaches T3 at time t3, the target current value is changed (reset) from I3 to I4 by the charging control unit 45, and the charging current drops from I3 to I4 (corresponding to S10). After the charging current drops to I4, the charging is continued in the state where the charging current is maintained at I4 by the constant current control (corresponding to the repetition of S9, S10, S11 and S12). At time t3, the charging voltage drops again as the charging current drops, but after time t3, the charging voltage further increases as the charging continues, and reaches a predetermined target charging voltage at time t5. When the charging voltage reaches the target charging voltage, the charging control unit 45 shifts to constant voltage control, and after time t5, charging is continued with the charging voltage being maintained at the target charging voltage (S9, S10, S11 and Equivalent to the repetition of S12). On the other hand, the battery temperature further rises after time t3, but at time t5, it does not reach the next temperature threshold value T4 used for changing the target current value.

  After time t5 when the constant voltage control is performed, charging is continued while the charging voltage is maintained at the target charging voltage, but the charging current decreases, and the battery temperature also decreases as the charging current and the first fan. 5 and the second fan 6 are driven to decrease (equivalent to the repetition of S9, S10, S11, and S12). After that, at time t7, when the charging current becomes equal to or less than the predetermined termination current value, the charging control unit 45 determines that the battery is fully charged (S10: Yes), and the charging is finished (S13). In FIG. 15A, the charging current is switched when the battery temperature reaches a predetermined value regardless of the charging voltage (battery voltage).

  As shown in FIG. 15B, when the battery pack 33 is charged by the charging device 1 according to the present embodiment, at time t0, the charging control unit 45 sets the target current value to I1 (the present embodiment). 12A), that is, a charging current of 2C is set for the nominal capacity 6Ah of the battery pack 33 (corresponding to S5), and charging is started with the charging current I1 (corresponding to S6). When the battery pack 33 is charged, unlike the case where the battery pack 3 is charged, the target current value is not changed according to the battery temperature (S9: No, the process of S10 is not performed), and the charging is started. Until the charging voltage reaches the target charging voltage (during constant current control), the charging current is constantly charged in the state of being maintained at I1 (corresponding to the repetition of S9, S11 and S12). This is because, as described above, the battery packs 3 and 33 both have the nominal capacity of 6 Ah, but have the breaking elements having different allowable charging current values and different breaking characteristics. Both the battery temperature and the charging voltage increase with the charging after time t0, and reach a predetermined target charging voltage at time t4.

  After time t4 when the charging voltage reaches the target charging voltage, charging is continued in the state where the charging voltage is maintained at the target charging voltage, but the charging current decreases and the battery temperature decreases as well as the charging current. It decreases due to the driving of the first fan 5 and the second fan 6 (corresponding to the repetition of S9, S11, and S12). After that, at time t6, when the charging current becomes equal to or lower than the predetermined termination current value, the charging control unit 45 determines that the battery is fully charged (S10: Yes), and the charging is terminated (S13).

  As described above, since the charging of the battery pack 33 is performed with the charging current of 2C from the start of charging to the shift to the constant voltage control, the charging end of the battery pack 33 is earlier than the charging end time t7 of the battery pack 3. Is time t6. In the present embodiment, the time from time t0 to time t6, that is, the charging time of battery pack 33 by charging device 1 is approximately 30 minutes, and the time from time t0 to time t7, that is, charging device 1 The charging time of the battery pack 3 is about 40 minutes.

  Here, a time change of the battery temperature, the charging voltage, and the charging current of the battery pack when the charging control by the conventional charging device is performed will be described. FIG. 15C is a time chart showing changes over time in battery temperature, charging voltage, and charging current when charging control is performed by the conventional charging device.

  As shown in FIG. 15(c), in the conventional charging device, the breaking characteristic (breaking characteristic curve) of the breaking element of the battery pack to be charged in the present embodiment is taken into consideration. The charging current switching control is not performed (the process corresponding to S10 in FIG. 12 is not performed). Further, in the conventional charging device, when the charging current is charged at 2C or more, the blocking element operates in a short time, and the charging is interrupted or terminated, so the charging current is set to be less than 2C. That is, in the conventional charging device, the charging current is set to 8 A so that the breaking element does not operate. FIG. 15C shows a case where a conventional battery charger is used to charge a battery pack having the same nominal capacity as the battery packs 3 and 33 of the present embodiment with 8 A (charging current of less than 2 C), for example. Is shown.

  In the conventional charging device, when charging is started at time t0, the time to reach the target charging voltage is t7, the charging end time is t8, and the charging time is about 45 minutes. Comparing the charging device 1 and the conventional charging device in terms of charging time with respect to a battery pack having the same capacity, it takes approximately 30 minutes to charge the battery pack 33 with the charging device 1 and to charge the battery pack 3 with the charging device 1. Approximately 40 minutes, and the charging time in the conventional charging device is approximately 45 minutes. In this way, both the charging time of the battery pack 3 and the charging time of the battery pack 33 by the charging device 1 are shorter than the charging time of the conventional charging device.

  As described above, in the charging device 1 according to the first embodiment of the present invention, the battery pack 3 including the battery group 3A having the battery cells 3a can be directly charged from the commercial AC power source P, and the nominal capacity is 6 Ah (5 Ah. The battery pack 3 described above can be charged with a charging current of 2C (preferably a charging current of 2C or more and 3C or less). In other words, the battery pack having a nominal capacity of α (α is a real number of 5 or more) Ah or more can be charged with a charging current of 2αA or more (preferably a charging current of 2α or more and 3α or less). Therefore, a high capacity battery pack can be charged in a short time of about 30 minutes.

  In addition, the charging device 1 allows the charging current to flow through the battery cells 3a when the blocking characteristic is satisfied, and when the charging characteristic is not satisfied, the first blocking element 3F (second blocking element) that blocks the charging current. The battery pack 3 (battery pack 33) including the element 33F) can be charged. Further, the plurality of terminals 70 connectable to the battery pack 3 (battery pack 33) and the interruption characteristics of the first interruption element 3F (second interruption element 33F), that is, the first interruption characteristic curve A (second interruption characteristic curve B). ) Is specified and charging control is performed so as to satisfy the cutoff characteristic. Therefore, the charging current is not blocked by the first blocking element 3F (second blocking element 33F), and charging is not interrupted or terminated. Thereby, the high capacity battery pack 3 (battery pack 33) can be charged with a charging current of 2C, and the high capacity battery pack 3 (battery pack 33) can be charged in a short time.

  Further, in the present embodiment, the cutoff characteristic of battery pack 3 (battery pack 33) is satisfied when the charging current is smaller than the maximum allowable current value corresponding to the battery temperature of battery cell 3a, and charging device 1 A charge control unit 45 that acquires the battery temperature of the battery pack 3 (battery pack 33), a current setting circuit 56 that can set one current value from a plurality of current values (I1 to I5), and the set current value. The current control circuit 57 controls the charging current so as to charge the battery pack 3 (battery pack 33) with one current value, and the charging control unit 45 can be set based on the battery temperature. Among I1 to I5, the charging current is controlled so that the battery pack 3 (electric pack 33) is charged at the maximum current value among the current values smaller than the allowable maximum current value corresponding to the battery temperature. Note that, in the present embodiment, in the case of S9: No shown in FIG. 12, that is, when the charging target is the battery pack 33, switching control of the charging current according to the cutoff characteristic (S10) is performed. However, the charging current switching control (S10) may be performed on the battery pack 33.

  According to the above configuration, for example, when the current value smaller than the allowable maximum current value of the plurality of settable current values (I1 to I5) is I2 to I5, the maximum current value among I2 to I5 is set. The battery pack 3 (battery pack 33) can be charged with the current value I2. Therefore, the charging time can be further shortened.

  Further, in the present embodiment, the maximum allowable current value in the cutoff characteristic of battery pack 3 (battery pack 33) becomes smaller as the battery temperature rises, and charge control unit 45 raises the battery temperature. The charging current is reduced accordingly. That is, in the charging device 1, since the charging current can be changed according to the interruption characteristic of the first interruption element 3F (second interruption element 33F), the first interruption element 3F (second interruption element 33F) is used. It is possible to reliably avoid interruption of the charging current. Thereby, the charging time can be surely shortened.

  Further, in the present embodiment, the charging control unit 45 controls the charging current so that when the battery temperature becomes T1 or higher, the charging current is charged by I2 which is smaller than I1, when charging by I1. Further, T1 is set lower than the battery temperature, that is, Ta, whose corresponding maximum allowable current value is I1. This makes it possible to more reliably avoid the interruption of the charging current by the first interruption element 3F (second interruption element 33F).

  More specifically, the maximum allowable current value corresponding to Ta is I1, and when charging is performed at I1, the charging current is blocked by the first blocking element 3F when the battery temperature reaches Ta. With the configuration, when the battery temperature reaches T1 lower than Ta, the battery current is changed from I1 to I2, which is smaller, so that the blocking of the charging current by the blocking element can be more reliably avoided.

  In addition, in the present embodiment, when charging with I2, the charging control unit 45 controls the charging current such that when the battery temperature is T2 higher than T1, it is charged with I3 smaller than I2. There is. Further, T2 is set to be lower than the battery temperature, that is, Tb whose corresponding maximum allowable current value is I2, and higher than T2. As a result, the interruption of the charging current by the first interruption element 3F can be more reliably avoided and the charging time can be further shortened.

  More specifically, the temperature threshold value T2 for changing the charging current from I2 to smaller I3 is lower than Tb, so that the operation of the first blocking element 3F can be reliably avoided. Furthermore, T2 is not higher than Ta, that is, not too low. If T2 is set to an excessively low value, for example, if it is set to a value lower than Ta, the operation of the first cutoff element 3F can be reliably avoided, but the charging current I2 is smaller than I3. The timing of changing to is too early to shorten the charging time sufficiently. In this respect, by setting T2 higher than Ta as in the present embodiment, the timing of changing to a smaller current value can be delayed and the charging time can be further shortened. Further, the charging device 1 can selectively charge a plurality of battery packs having different voltages and different nominal capacities, so that if one charging device 1 is prepared, it is possible to charge a plurality of battery packs. There is no need to prepare a charging device. Furthermore, since a battery pack having a nominal capacity of less than 5 Ah can be charged with a charging current of 2 C or more, the charging time of a low capacity (less than 5 Ah) battery pack can be shortened.

  Next, a modification of the first embodiment will be described with reference to FIGS. 16 to 20.

  In the charging device 1 of this modified example, a heat dissipation plate 80 is used instead of the heat dissipation members 46 and 47. The rest of the configuration is the same as that of the first embodiment, so its explanation is omitted.

  The heat dissipation plate 80 defines an air passage as cooling air for the air taken in from the intake port 24a and guides it toward the exhaust ports 22a and 23a.

  As shown in FIG. 16, the heat dissipation plate 80 has a size that covers the heating elements such as the diode 41, the transformer 42, and the FET 43 as shown in FIGS. 16 to 18 when mounted in the case 2 of the charging device 1. It has a shape and a shape and is arranged between the upper surface 21 of the case 2 and the diode 41, the transformer 42, and the FET 43.

  In the heat dissipation plate 80, openings 81, 82, 83, 84, 85 having a shape corresponding to the outer shape of each element are formed at positions corresponding to the diode 41, the transformer 42, and the FET 43. Further, ribs 81A, 82A, 83A, 84A, 85A are formed toward the substrate 40 from the vicinity of the edges of the openings 81, 82, 83, 84, 85. For example, the air passage for the transformer 42 that reaches the opening 82 from the substrate side of the transformer 42 is defined by the opening 82 formed for the transformer 42 and the rib 82A. Similarly, an air passage for the diode 41 is defined by the diode 41, the opening 81, and the rib 81A, and an air passage is defined for the heat generating elements including the FET 43.

  Therefore, when the heat dissipation plate 80 is installed in the case 2, the ribs 81A, 82A, 83A, 84A, 85A having the openings 81, 82, 83, 84, 85 provided at the peripheral portions of the openings 81, 82, 83A, 84A, 85A are also generated. The element is surrounded by a slight gap. That is, the heating element is surrounded by the ribs 81A to 85A.

  Therefore, when the fans 5 and 6 are driven, as shown in FIGS. 18 to 20, from the intake port 24a to the exhaust port 22a via the air passage and the opening formed around the corresponding heating element. A cooling air passage leading to 23a is formed. The first cooling air and the second cooling air pass through this cooling air passage to cool each of the diode 41, the transformer 42, and the FET 43, which are heating elements. In the vicinity of each heating element, an air passage is defined between the side surface of the heating element and the corresponding rib, and cooling air flows toward the opening along the side surface of the heating element. The cooling air that has passed through the openings flows along the heat dissipation plate 80 toward the exhaust ports 22a and 23a and is exhausted to the outside of the case 2. Therefore, since the cooling air is concentrated around the heating element by the ribs, the heating element is efficiently cooled and the temperature rise of the entire charging device 1 is suppressed.

  Next, a second embodiment of the present invention will be described with reference to FIGS.

  Referring to FIG. 21, the charging device 1 includes, inside the case 102, a charging circuit unit 104 for charging the battery pack 3, a first fan 105 for cooling the charging circuit unit 104 and the battery pack 3, and a first fan 105 for cooling the battery pack 3. Two fans 106 are provided.

  The case 102 has a substantially rectangular parallelepiped shape, and the upper surface 121 is provided with a battery mounting portion 107 on the front side to which the battery pack 3 is mounted for charging. The battery mounting portion 107 is provided with a plurality of terminals 170 for charging the battery pack 3 and an opening 171 through which air for cooling the battery pack 3 passes. Further, the case 102 has four side surfaces 122, 123, 124, 125 surrounding the upper surface 121, and the side surfaces 122, 123 adjacent to each other are connected by a corner portion 126. The side surfaces 122 and 124 face each other, and the side surfaces 123 and 125 face each other.

  The first fan 105 is arranged in the case 102 so as to be close to the corner portion 126 and the opening 171 and to face the side surface 122. When driven, the first fan 105 generates the first cooling air in the rotation axis direction X. A first exhaust port 122a composed of a plurality of ventilation windows is formed in the side surface 122 facing the first fan 105. When driven, the first fan 105 takes in air from the intake port 124a and generates a first cooling air flowing toward the first exhaust port 122a. The first cooling air is exhausted from the case 102 via the first exhaust port 122a.

  The second fan 106 is arranged in the case 102 so as to be close to the corner portion 126 and the opening 171 and to face the side surface 123. When driven, the second fan 106 generates second cooling air in the rotation axis direction Y. At this time, the second fan 106 is arranged so that the rotation axis direction Y intersects with the rotation axis direction X of the first fan 105. A second exhaust port 123a composed of a plurality of ventilation windows is formed on the side surface 123 facing the second fan 106. When driven, the second fan 106 takes in air from the intake port 124a and generates second cooling air flowing toward the second exhaust port 123a. The second cooling air is exhausted from the case 102 via the second exhaust port 123a.

  The intake port 124a is formed as a plurality of ventilation windows over a predetermined range of the side surface 124 of the case 102. Therefore, when the first and second fans 105 and 106 are driven, the air is taken into the case 102 through the air inlet 124a.

  The charging circuit unit 104 is mainly provided with the diode 141, the transformer 142, the FET 143, the temperature detecting element 144, and the charge control unit 45 on the substrate 140, and uses electric power supplied from, for example, a commercial AC power source. The battery pack 3 is charged via the terminal 170. When a large amount of current per unit time is passed through the charging circuit unit 104 for quick charging, the diode 141, the transformer 142, and the FET 143 tend to generate heat, and become so-called heat generating elements. In order to protect these components from heat generation and radiate heat, for example, heat radiation members 146 and 147 are attached to the diode 141 and the FET 143, respectively.

  The diode 141, the transformer 142, and the FET 143 are arranged near the intake port 124a and are directly exposed to the air introduced into the case 102 from the intake port 124a.

  The case 102 has an opening 171 on the upper surface 121, and a first exhaust port 122a, a second exhaust port 123a, and an intake port 124a on the side surface. The flow of air in the case 102 is mainly between the opening 171, the first exhaust port 122a and the second exhaust port 123a, and between the intake port 124a and the first exhaust port 122a and the second exhaust port 123a. , Is formed. The heat radiating members 146, 147 include at least one, preferably all of the diode 141, the transformer 142 and the FET 143 in the air passage formed between the intake port 124a and the first exhaust port 122a and the second exhaust port 123a. Each shape and the position in the case 102 are set so as to include them. The diode 141 and the FET 143 are attached to the heat dissipation members 146 and 147 so that the diode 141 and the FET 143 can be cooled by the first and second cooling air in the case 102. The heat dissipation members 146 and 147 do not have the second heat dissipation part.

  The temperature detection element 144 is formed of, for example, a thermistor, and detects the temperature inside the case 102.

  The charging control unit 45 controls the charging of the battery pack 3 by the charging circuit unit 104 while monitoring the temperature of the battery pack 3, and also controls the rotation of the first and second fans 105 and 106.

  When the battery pack 3 is being charged, the two fans 105 and 106 are operating in the case 102, so that the cooling air taken into the case 2 from the intake port 124a is the diode 41 and the transformer. 42, the heat generating elements are cooled by passing near the FET 43, and are exhausted from the exhaust ports 122a and 123a. Therefore, the temperature rise of the diode 41, the transformer 42, and the FET 43 can be prevented, and the charging device 100 can be cooled efficiently.

  In addition, the heat dissipation members 146 and 147 define an air passage so as to surround the diode 141, the transformer 142, and the FET 143, and the first cooling air and the second cooling air are mainly close to the intake ports of the heat dissipation members 146 and 147. Since it flows from the one end side toward the other end side, the diode 141, the transformer 142, and the FET 143, which need to be cooled, can be efficiently cooled. Further, since the diode 141 and the FET 143 are attached to the heat dissipation members 146 and 147, respectively, the diode 141 and the FET 143 are exposed to the cooling air flowing along the heat dissipation members 146 and 147 and are efficiently cooled.

  Further, since the first fan 105 and the second fan 106 are arranged so that their rotation axis directions intersect with each other, and are provided at the corner portion 126 of the case 102, an area for the charging circuit unit 104 is provided. Can be made large in the case 102. Further, it is possible to widen the passage area of the cooling air.

  Further, since the diode 141, the transformer 142, and the FET 143 are arranged in the vicinity of the intake port 124a, the air before being warmed immediately after being sucked in from the intake port 124a is cooled as cooling air, so that it is cooled efficiently. It The flow of cooling air may be reversed. That is, the air may be sucked in by using the exhaust ports 122a and 123a as intake ports, and the air may be discharged by using the intake port 124a as exhaust ports.

  Next, a modified example of the second embodiment will be described below with reference to FIGS. 23 to 28.

  FIG. 23 shows a charging device 100A in which the first fan 105 and the second fan 106 are juxtaposed close to the side surface 123 of the rectangular parallelepiped case 102. The intake port 124a is formed on the side surface 125 that faces the side surface 123. Since the other components are the same as those in the second embodiment, detailed description thereof will be omitted. When the first fan 105 and the second fan 106 are driven, the first cooling air and the second cooling air flow from the air inlet 124a toward the air outlets 122a and 123a, and the diode 141 disposed in the air passage. , The transformer 142 and the FET 143 are cooled. That is, the heat radiating members 146, 147 are arranged so as to extend from the intake port 124a toward the exhaust ports 122a, 123a (in the front-back direction in the drawing) so as to guide the cooling air, and the transformer 142 is arranged between the heat radiating members 146, 147. is doing. By providing the two fans 105 and 106 in the case 102, it is possible to increase the air volume and the passage area of the cooling air to enhance the cooling effect of the heating elements 141, 142 and 143, and further the charging device 100A.

  FIG. 24 shows a charging device 100B in which the first fan 105 and the second fan 106 are juxtaposed close to the side surface 122 of the case 102. The intake port 124a is formed on the side surface 124 that faces the side surface 122. Since the other components are the same as those in the second embodiment, detailed description thereof will be omitted. When the first fan 105 and the second fan 106 are driven, the first cooling air and the second cooling air flow from the air inlet 124a toward the air outlets 122a and 123a, and the diode 141 disposed in the air passage. , The transformer 142 and the FET 143 are cooled. That is, the heat radiating members 146 and 147 are arranged so as to extend from the intake port 124a toward the exhaust ports 122a and 123a (in the horizontal direction in the drawing) so as to guide the cooling air, and the transformer 142 is arranged between the heat radiating members 146 and 147. is doing. By providing the two fans 105 and 106 in the case 2, it is possible to increase the air volume and the passage area of the cooling air to enhance the cooling effect of the heating elements 141, 142 and 143, and further the charging device 100A. The flow of cooling air may be reversed. That is, the air may be sucked in by using the exhaust ports 122a and 123a as intake ports, and the air may be discharged by using the intake port 124a as exhaust ports.

  FIG. 25 shows a charging device 100C in which the first fan 105 and the second fan 106 are juxtaposed in the vertical direction near the side surface 125 of the case 102. An exhaust port is formed on the side surface 125 near the fans 105 and 106, and an intake port is formed on the side surface 123 facing the side surface 125. Since the other components are the same as those in the second embodiment, detailed description thereof will be omitted. When the first fan 105 and the second fan 106 are driven, the first cooling air and the second cooling air flow from the intake port toward the exhaust port, and the diode 141, the transformer 142 disposed in the air passage, The FET 143 is cooled. By providing the two fans 105 and 106 in the case 2, it is possible to increase the air volume and enhance the cooling effect of the heating elements 141, 142 and 143 and further the charging device 100A. Here, in FIG. 25, the heat radiating members 146 and 147 are arranged so as to block the cooling air passages from the intake port 124a toward the exhaust ports 122a and 123a, but heat radiation is performed so as to guide the cooling air as in FIG. By disposing the members 146 and 147, the cooling effect can be enhanced. At that time, if the transformer 142 is arranged between the heat dissipation members 146 and 147 and close to the intake port 124a, the cooling effect of the transformer 142 can be enhanced in addition to the diode 141 and the FET 143. The flow of cooling air may be reversed. That is, the air may be sucked in by using the exhaust ports 122a and 123a as intake ports, and the air may be discharged by using the intake port 124a as exhaust ports.

  FIG. 26 shows a charging device 100D in which the first fan 105 and the second fan 106 are juxtaposed close to each other on the upper surface 121 of the case 102, apart from the battery mounting portion 107. An intake port is formed on the upper surface 121 near the fans 105 and 106, and an exhaust port is formed on the side surface 123. Since the other components are the same as those in the second embodiment, detailed description thereof will be omitted. When the first fan 105 and the second fan 106 are driven, the first cooling air and the second cooling air flow from the intake port toward the exhaust port, and the diode 141, the transformer 142 disposed in the air passage, The FET 143 is cooled. By providing the two fans 105 and 106 in the case 2, it is possible to increase the air volume and enhance the cooling effect of the heating elements 141, 142 and 143 and further the charging device 100A. Further, since the two fans 105 and 106 are arranged along the upper surface 121, a space for disposing the substrate 140 can be secured. It is also possible to arrange the two fans 105 and 106 along the upper surface 121 and the side surfaces 122 or 124. Note that, similarly to FIG. 25, if the heat dissipation members 146 and 147 are arranged along the cooling air passage, the cooling effect can be further enhanced. The flow of cooling air may be reversed. That is, an exhaust port may be formed on the upper surface near the fan, and the exhaust port 123a of the side surface 123 may be used as an intake port to suck air.

  FIG. 27 shows a charging device 100E in which the first fan 105 is arranged near the side surface 125 and the second fan 106 is arranged near the side surface 123. That is, the first fan 105 and the second fan 106 are arranged on both sides of the charging circuit unit 104 with being separated from each other. The intake port is formed on the side surface 125, and the exhaust port is formed on the side surface 123. Since the other components are the same as those in the second embodiment, detailed description thereof will be omitted. When the first fan 105 and the second fan 106 are driven, the first cooling air and the second cooling air flow from the intake port toward the exhaust port, and the diode 141, the transformer 142 disposed in the air passage, The FET 143 is cooled. By providing two fans 105 and 106 in the case 102 and driving one for intake and the other for exhaust, the air volume of the cooling air flowing in the case 2 is increased and the heating elements 141, 142, 143, and further. The cooling effect of the charging device 100A can be enhanced.

  FIG. 28 shows a charging device 100F in which the first fan 105 is arranged near the corners of the side surface 124 and the side surface 125, and the second fan 106 is arranged near the corner portion 126. That is, the first fan 105 and the second fan 106 are arranged on both sides of the charging circuit unit 104 with being separated from each other. The intake port is formed on the side surface 125, and the exhaust port is formed on the side surface 123. Since the other components are the same as those in the second embodiment, detailed description thereof will be omitted. When the first fan 105 and the second fan 106 are driven, the first cooling air and the second cooling air flow from the intake port toward the exhaust port, and the diode 141, the transformer 142 disposed in the air passage, The FET 143 is cooled. By providing two fans 105 and 106 in the case 102 at both ends in a diagonal direction, and driving one for intake and the other for exhaust, the air passage of cooling air flowing in the case 2 is made long. This can enhance the cooling effect of the heating elements 141, 142, 143, and further the charging device 100F. The cooling effect can be further enhanced by disposing the heat dissipation members 146 and 147 along the cooling air passage (arrows in the figure). The flow of cooling air may be reversed. That is, the air may be sucked from the side surface 123 side and the air may be discharged from the side surface 125 side.

  Next, a charging device 200 according to the third embodiment will be described below with reference to FIG. Regarding the charging device 200, the same members as those of the first embodiment are designated by the same reference numerals, and different parts will be mainly described below.

  Referring to FIG. 29, the charging device 200 includes, inside the case 202, a charging circuit unit 204 for charging the battery pack 3, a first fan 205 for cooling the charging circuit unit 204 and the battery pack 3, and a first fan unit 205. Two fans 206 are provided.

  The case 202 has a substantially rectangular parallelepiped shape, and the upper surface 221 is provided with a battery mounting portion 207 on the front side to which the battery pack 3 is mounted for charging. The battery mounting portion 207 is provided with a plurality of terminals 270 for charging the battery pack 3 and an opening 271 through which air for cooling the battery pack 3 passes. Further, the case 202 has four side surfaces 222, 223, 224, 225 surrounding the upper surface 221, and the side surfaces 222, 223 adjacent to each other are connected by a corner portion 226.

  The first fan 205 is arranged inside the case 202, close to the corner portion 226 and the opening 271, and opposite to the side surface 222. A first ventilation port 222a including a plurality of ventilation windows is formed in a portion of the side surface 222 facing the first fan 205. When driven, the first fan 205 sucks air from the first ventilation port 222a and generates the first cooling air having the rotation axis direction X as the blowing direction.

  The second fan 206 is arranged inside the case 202, close to the corner portion 226 and the opening 271, and facing the side surface 223. A second ventilation port 223a including a plurality of ventilation windows is formed in a side surface 223 portion facing the second fan 206. When driven, the second fan 206 sucks air from the second ventilation port 223a and generates the second cooling air with the rotation axis direction Y as the air blowing direction. The second fan 106 is arranged so that the rotation axis direction Y intersects with the rotation axis direction X of the first fan 5.

  The first ventilation port 222a and the second ventilation port 223a function as an intake port that takes in air into the case 202 while the battery pack 3 is being charged.

  Further, a plurality of exhaust windows are formed on the side surface 224 of the case 202 as exhaust ports 224a over a predetermined range, and the first and second fans 205 and 206 are driven to drive the first and second exhaust windows 224a. 2 The cooling air is exhausted to the case 202.

  The charging circuit unit 204 is mainly provided with the diode 241, the transformer 242, the FET 243, the temperature detecting element 244, and the charging control unit 45 on the substrate 240, and uses electric power supplied from a commercial AC power source, for example. The battery pack 3 is charged via the terminal 270. When a large amount of current per unit time is passed through the charging circuit section 204 for quick charging, the diode 241, the transformer 242, and the FET 243 tend to generate heat, and become so-called heat generating elements. In order to protect these components from heat generation and radiate heat, for example, heat radiation members 246 and 247 are attached to the diode 241 and the FET 243, respectively.

  The diode 241, the transformer 242, and the FET 243 are arranged near the exhaust port 224a and are directly exposed to the first and second cooling air exhausted from the exhaust port 224a to the outside of the case 202.

  The case 202 has an opening 271 on the upper surface 221, and a first vent 222a, a second vent 223a, and an exhaust port 224a on the side surface. The air flow in the case 202 is mainly between the first and second fans 205 and 206 and the opening 271, and between the first vent 222a and the second vent 223a and the exhaust port 224a. It is formed. The heat dissipation members 246 and 247 particularly form an air passage between the first vent 222a and the second vent 223a and the exhaust port 224a. Then, each shape and the position within the case 202 are set so that at least one, preferably all of the diode 241, the transformer 242 and the FET 243 are included in the air passage. Further, the diode 241 and the FET 243 are attached to the heat dissipation members 246 and 247 so that the diode 241 and the FET 243 in the case 202 can be cooled by the first and second cooling air.

  The temperature detection element 244 is formed of, for example, a thermistor, and detects the temperature inside the case 202.

  The charging control unit 45 controls the charging of the battery pack 3 by the charging circuit unit 204 while monitoring the temperature of the battery pack 3, and also controls the rotation of the first and second fans 205 and 206.

  Next, the first operation of the charging device 200 will be described with reference to FIG.

  When the charging device 200 is connected to, for example, a commercial power source, the charging control unit 45 determines in S111 whether or not the battery pack 3 is mounted in the battery mounting unit 207. When the battery pack 3 is attached (S111: Yes), in S112, the first fan 205 is turned on and driven for 5 seconds, and the second fan 206 is kept off. At this time, as shown in FIG. 31, due to the driving of the first fan 205 and the turning off of the second fan 206, the air sucked from the first ventilation port 222a becomes the second cooling air from the first fan 205. The air is blown toward the ventilation port 223a and the exhaust port 224a. The first cooling air flowing toward the second ventilation port 223a is exhausted to the outside of the case 202 through the second ventilation port 223a and blows out dust and the like attached to the second ventilation port 223a to the outside of the case 202.

  Next, in S113, the first fan 205 is turned off and stopped, and the second fan 206 is turned on and driven for 5 seconds. At this time, as shown in FIG. 32, the air sucked from the second ventilation port 223a by the first fan 205 being turned off and the second fan 206 being driven, the first cooling air from the second fan 206 becomes the first cooling air. The air is blown toward the ventilation port 222a and the exhaust port 224a. The second cooling air flowing toward the first ventilation port 222a is exhausted to the outside of the case 202 through the first ventilation port 222a and blows out dust and the like attached to the first ventilation port 222a to the outside of the case 202.

  Note that the times in S112 and S113 are each 5 seconds in the present embodiment, but the time is not limited to this time, and may be an appropriate length of time.

  Next, in S114, the charging of the battery pack 3 is started, and at the same time, the first and second fans 205 and 206 are both turned on in S115. As shown in FIG. 33, the first and second fans 205 and 206 generate the first and second cooling winds, so that air is taken into the case 202 through the first ventilation holes 222a and 223a. An air passage is formed toward the exhaust port 224a. Further, an air passage extending from the first ventilation openings 222a and 223a toward the opening 271 is also formed.

  When the charging of the battery pack 3 is completed in S116, the charging control unit 45 confirms in S117 whether the temperature of the battery pack 3 is 40 degrees or higher. If the temperature of the battery pack 3 is 40 degrees or more (S117: Yes), the drive of the 1st and 2nd fans 205 and 206 is continued (S118), and the cooling of the battery pack 3 is continued.

  If the temperature of the battery pack 3 is less than 40 degrees (S117: No), it is confirmed whether the temperature of the charging circuit unit 204 is 40 degrees or more (S119). If the temperature of the charging circuit unit 204 is 40 degrees or more (S119: Yes), the driving of the first and second fans 205 and 206 is continued (S120) and the cooling of the charging circuit unit 204 is continued. If the temperature of the charging circuit unit 204 is less than 40 degrees (S119: No), the driving of the first and second fans 205 and 206 is stopped (S121).

  On the other hand, if the battery pack 3 is not attached in S111 (S111: No), in S122, the first fan 205 is turned on and driven for 5 seconds, and the second fan 206 is maintained in the off state. . At this time, as shown in FIG. 31, due to the driving of the first fan 205 and the turning off of the second fan 206, the air sucked from the first ventilation port 222a becomes the second cooling air from the first fan 205 to the second cooling air. The air is blown toward the ventilation port 223a and the exhaust port 224a. The first cooling air flowing toward the second ventilation port 223a is exhausted to the outside of the case 202 through the second ventilation port 223a and blows out dust and the like adhering to the second ventilation port 223a to the outside of the case 202.

  Next, in S123, the first fan 205 is turned off and stopped for 5 seconds, and the second fan 206 is turned on and driven. At this time, as shown in FIG. 32, the air sucked from the second ventilation port 223a due to the turning off of the first fan 205 and the driving of the second fan 206 causes the first cooling air to flow from the second fan 206 to the first cooling air. The air is blown toward the ventilation port 222a and the exhaust port 224a. The second cooling air flowing toward the first ventilation port 222a is exhausted to the outside of the case 202 through the first ventilation port 222a and blows out dust and the like attached to the first ventilation port 222a to the outside of the case 202.

  Note that the times in S122 and S123 are each 5 seconds in the present embodiment, but the time is not limited to this time, and may be an appropriate length of time.

  Next, in S124, the first fans 205 and 206 are stopped. Next, proceeding to S125, the charging device 200 waits at S125 until the battery pack 3 is attached.

  In the charging device 200 according to the second embodiment, the first vent 222a and the second vent 223a of the case 202, which are used as intake ports while the battery pack 3 is being charged, are different from those of the case 202 in S113 and 112. Since it functions as an exhaust port for exhausting air to the outside, it is possible to remove dust and the like adhering to the first vent 222a and the second vent 223a from the first vent 222a and the second vent 223a by the exhaust. Becomes

  The diode 241, the transformer 242, and the FET 243, which are heating elements, are provided near the exhaust port 224a. Since the first and second cooling winds are focused on the exhaust port 224a for exhausting to the outside of the case, the diode 241, the transformer 242, and the FET 243 are cooled by a relatively high air volume, so that the diode 241 and the transformer 242 can be efficiently used. , 243 can be cooled.

  In addition, since the first fan 205 and the second fan 206 are arranged in the case 202 such that the air blowing directions thereof intersect with each other, the cooling area in the case 202 by the first and second cooling air should be widened. You can Therefore, not only the battery pack 3 being charged but also various electronic components such as the diode 241, the transformer 242, the FET 243, and the like, including the heating elements in the case 202, can be appropriately cooled and protected from heat generation.

  Next, the second operation of the charging device 200 will be described with reference to FIG.

  When the charging device 200 is connected to, for example, a commercial power source, in S31, it is determined whether or not the battery pack 3 is mounted in the battery mounting portion 7. When the battery pack 3 is attached (S31: Yes), the charge control unit 45 proceeds to S32 and starts charging the battery pack 3. At the same time, in S33, the first fan 205 is turned on to start driving at the same 100% rotation speed as that during charging of the battery pack 3. At this time, the second fan 206 is also turned on and driven, but if the charging of the battery pack 3 is 100%, the second fan 206 is driven for 5 seconds at a rotation speed of 20%. At this time, as shown in FIG. 35, the air is sucked from the second ventilation port 223a by the drive of the second fan 206, but since the rotation speed of the first fan 205 is higher than the rotation speed of the second fan 206, A part of the first cooling air generated by the first fan 205 is exhausted to the outside of the case 202 via the second ventilation port 223a. Therefore, a part of the first cooling air blows off dust and the like attached to the second ventilation port 223a to the outside of the case 202.

  Next, in S34, the second fan 206 is started to be driven at the same 100% rotation speed as when the battery pack 3 is being charged. At this time, the first fan 205 is driven at a rotation speed of 20% for 5 seconds, assuming that the battery pack 3 is 100% charged. At this time, as shown in FIG. 36, the air is sucked from the first ventilation port 222a by driving the first fan 205, but since the rotation speed of the second fan 206 is higher than the rotation speed of the first fan 205, A part of the second cooling air generated by the second fan 206 is exhausted to the outside of the case 202 via the first ventilation port 222a. Therefore, dust and the like attached to the first vent 222a are blown out of the case 202 by a part of the second cooling air.

  Note that the times in S33 and S34 are each 5 seconds in the present embodiment, but the time is not limited to this, and may be an appropriate length of time. Further, although the rotation speeds of the second fan 206 and the first fan 205 in S33 and S34 are set to 20%, the present invention is not limited to this, and cooling air can be exhausted from the second ventilation port 223a or the first ventilation port 222a. An appropriate ratio is selected.

  Next, in S35, the first and second fans 205 and 206 are both driven to 100% to generate the first and second cooling air. The first and second cooling air cool the battery pack 3 during charging, and at the same time, cool the diode 241, the transformer 242, and the heat generating elements such as the FET 243 in the case to protect these heat generating elements from heat. ..

  When the charging of the battery pack 3 is completed in S36, the charging control unit 45 confirms in S37 whether the temperature of the battery pack 3 is 40 degrees or higher. If the temperature of the battery pack 3 is 40 degrees or more (S37: Yes), the drive of the 1st and 2nd fans 205 and 206 is continued (S38), and the cooling of the battery pack 3 is continued.

  If the temperature of the battery pack 3 is less than 40 degrees (S37: No), it is confirmed whether the temperature of the charging circuit unit 204 is 40 degrees or more (S39). If the temperature of the charging circuit unit 204 is 40 degrees or more (S39: Yes), the driving of the first and second fans 205 and 206 is continued (S40) and the cooling of the charging circuit unit 204 is continued. If the temperature of the charging circuit unit 204 is less than 40 degrees (S39: No), the driving of the first and second fans 205 and 206 is stopped (S41).

  On the other hand, when the battery pack 3 is not attached in S31 (S31: No), the first fan 205 is turned on and driven for 5 seconds and the second fan 206 is kept off in S42. .. At this time, the air sucked from the first ventilation port 222a due to the driving of the first fan 205 and the turning off of the second fan 206 causes the first cooling air to flow from the first fan 205 to the second ventilation port 223a and the exhaust port 224a. It is blown to and. The first cooling air flowing toward the second ventilation port 223a is exhausted to the outside of the case 202 through the second ventilation port 223a and blows out dust and the like attached to the second ventilation port 223a to the outside of the case 202.

  Next, in S43, the first fan 205 is turned off and stopped, and the second fan 206 is turned on and driven for 5 seconds. At this time, when the first fan 205 is turned off and the second fan 206 is driven, the air sucked from the second ventilation port 223a is used as the second cooling air from the second fan 206, the first ventilation port 222a and the exhaust port 224a. It is blown to and. The second cooling air flowing toward the first ventilation port 222a is exhausted to the outside of the case 202 through the first ventilation port 222a and blows out dust and the like attached to the first ventilation port 222a to the outside of the case 202.

  Next, in S44, each of the first fans 205 and 206 is stopped. Next, in S45, the charging device 200 waits in S45 until the battery pack 3 is mounted. When the mounting of the battery pack 3 is detected in S45, the process returns to S31.

  In the second operation of the charging device 200 according to the second embodiment, at the same time as the charging of the battery pack 3 is started, the rotation speed of one of the first and second fans 205, 206 is changed to that of the other fan. By making it larger than the rotation speed, the cooling air generated by the high rotation speed fan is exhausted from the ventilation opening corresponding to the low rotation speed fan, and adhered to the ventilation hole corresponding to the low rotation speed fan. Dust is blown out of the case 202. Next, the rotation speed of the fan is reversed between the first fan 205 and the second fan 206, so that dust and the like adhering to the other vent is blown out of the case 202. Therefore, it is possible to eliminate the clogging of the first and second ventilation ports that occurs during charging of the battery pack 3.

  The diode 241, the transformer 242, and the FET 243, which are heating elements, are provided near the exhaust port 224a. Since the first and second cooling winds are focused on the exhaust port 224a for exhausting to the outside of the case, the diode 241, the transformer 242, and the FET 243 are cooled by a relatively high air volume, so that the diode 241 and the transformer 242 can be efficiently used. , 243 can be cooled.

  Further, since the first fan 205 and the second fan 206 are arranged in the case 202 so that the air blowing directions of the first fan 205 and the second fan 206 intersect with each other, rather than arranging the air blowing directions of the two fans in parallel with each other, The cooling region in the case 202 by the first and second cooling air can be widened. Therefore, not only the battery pack 3 being charged but also various electronic components such as the diode 241, the transformer 242, the FET 243, and the like, including the heating elements in the case 202, can be appropriately cooled and protected from heat generation.

  In the above embodiment, the first vent 222a and the second vent 223a are separated by the corner 226. However, in another embodiment, the first vent 222a and the second vent 223a may be formed continuously over the side surfaces 222 and 223. Similarly, the first vent 222a and the second vent 223a are configured to be separated by the corner portion 226. However, in another embodiment, the first vent 222a and the second vent 223a may be formed continuously over the side surfaces 222 and 223.

  The charging device according to the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the invention described in the claims.

  For example, the air passage for the cooling air may be configured as shown in FIGS. 37 and 38. In the charging device 1 of the fourth embodiment, instead of the heat radiation plate 80 of the first embodiment for the cooling air passage, a plate 300 integrally formed with the case 2 together with the heat radiation members 46 and 47 is used. use. The rest of the configuration is the same as that of the first embodiment, so its explanation is omitted.

  The plate 300, together with the heat radiating members 46 and 47, defines an air passage as cooling air for the air taken in from the intake port 24a, and guides it toward the exhaust ports 22a and 23a.

  As shown in FIG. 37, the plate 300 is provided inside or integrally with the case 2 of the charging device 1 on the inner peripheral surface on the upper surface side of the case. When separated from the case 2, the case 2 is fixed to the inner peripheral surface of the case 2 by screws or the like (not shown). In the assembled state of the charging device 1, the plate 300 covers the heating elements such as the diode 41, the transformer 42, and the FET 43, that is, so as to cover the air passages formed by the heat radiating members 46 and 47. It is located above and has a size and shape along the longitudinal direction of the heat dissipation members 46 and 47. The plate 300 is arranged between the upper surface 21 of the case 2 and the diode 41, the transformer 42, and the FET 43.

  Although the upper portion of the transformer 42 is opened in the first embodiment, the transformer 42 is covered by the plate 300 in the present embodiment. Therefore, the cooling efficiency of the transformer 42 can be improved.

  Therefore, when the fans 5 and 6 are driven, as shown in FIG. 38, cooling from the intake port 24a to the exhaust ports 22a and 23a via the air passage formed by the heat dissipation members 46 and 47 and the plate 300 is performed. An airway is formed. The first cooling air and the second cooling air pass through this cooling air passage to cool each of the diode 41, the transformer 42, and the FET 43, which are heating elements. Since the heating element is covered by the plate 300 above each heating element, the cooling air reliably passes around the heating element, the heating element is efficiently cooled, and the temperature rise of the entire charging device 1 is suppressed. .

  Further, in the above-described embodiment, the battery pack and the heating element are cooled by providing a plurality of (two) fans. However, when a battery pack having a nominal capacity of 5 Ah or more is charged with a charging current of 2 C or more or 10 A or more, as long as the air volume is sufficient to cool the battery pack or the heating element, there may be a plurality of fans or only one fan. But it's okay.

  In the fifth embodiment, as shown in FIG. 39, a single fan 6 is used. The location of the fan may be any location such as the location of the fan 5 in FIG. 4 and the location of the fans 105 and 106 in FIGS. 27 and 28.

When charging the battery pack with a charging current of 10 A or more, the air volume in the case 2 by the single fan 6 is 13.0 m^3/hr (13 cubic meters per hour) or more, preferably 13.5 m^3/hr. By the above, it is possible to charge while suppressing the heat generation of the heating element. At that time, the wind pressure is preferably 0.0015 Pa or more. Further, as shown in FIG. 4 etc., the air volume generated in the case 2 by a plurality of fans may be set to 13.0 m^3/hr or more.
Therefore, when the battery pack is charged with a charging current of 10 A or more, a single fan may be used as long as the air volume in the case 2 can be 13 m^3/hr or more.

1, 100, 200 Charging device 2, 102, 202 Case 3, 33 Battery pack 3a Battery cell 3F First blocking element 4, 104, 204 Charging circuit unit 5, 105, 205 First fan 6, 106, 206 Second fan 7 Battery mounting part 22a, 122a 1st exhaust port 23a, 123a 2nd exhaust port 222a 1st ventilation port 223a 2nd ventilation port 33F 2nd interruption|blocking element 41, 141, 241 diode 42, 142, 242 transformer 43, 143, 243. FET
45 Charge Control Section 46, 47 Heat Dissipation Member 46A, 47A First Heat Dissipation Section 46B, 47B Second Heat Dissipation Section 56 Current Setting Circuit 57 Current Control Circuit 70 Terminal

Claims (8)

  An intake port that takes in air and an exhaust port that exhausts air are formed, and a case in which a battery pack can be mounted,
  A fan that generates cooling air in the case,
  A charging circuit unit that is provided in the case and configured to charge the battery pack, and has a plurality of heating elements that generate heat when the battery pack is charged,
  The plurality of heat generating elements have at least a first heat generating element, a second heat generating element, and a third heat generating element, and the first heat generating element and the second heat generating element respectively have heat of the heat generating element. A heat dissipation member for radiating heat is attached,
  The two heat radiating members are arranged so as to extend in opposition to each other so that the cooling air flows linearly between the two heat radiating members from the intake port toward the exhaust port,
  The charging device, wherein the third heating element is disposed between the two heat dissipation members.   The charging device according to claim 1, wherein the fan is arranged between the two heat radiating members on an extension of a direction in which the two heat radiating members extend.   The said fan is arrange|positioned in the downstream of the said 3rd heat generating element in the direction which the said cooling wind flows, The charging device of Claim 1 or 2 characterized by the above-mentioned.   At least one of the said 1st heat generating element and the said 2nd heat generating element is arrange|positioned between the said two heat dissipation members, The charging device as described in any one of Claim 1 to 3 characterized by the above-mentioned. .   5. The dimension of the two heat radiating members is larger than the dimension of the third heat generating element in a direction in which the cooling air flows between the two heat radiating members. The charging device according to.   Further having a second fan,
  The case is provided with a battery mounting portion on the upper surface of which the battery pack is mounted, and an opening through which wind for cooling the battery pack passes,
  The second fan is disposed below the battery mounting portion, and is configured to generate cooling air for cooling the battery pack through the opening. The charging device according to claim 5.   The charging device according to claim 6, wherein the cooling air generated by the second fan flows through an air passage different from the cooling air generated by the fan.   The charging device according to any one of claims 1 to 7, wherein the intake port and the exhaust port are formed on both sides of the case sandwiching the charging circuit unit.

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