JP5691397B2 - Electric pump - Google Patents

Description

  The present invention relates to an electric pump including a pump unit, a motor unit that drives the pump unit, and a driver unit that controls the motor unit.

  An example of such an electric pump is described in Patent Document 1. In this electric pump, the driver part can be driven and controlled by inserting a connector of a harness connected to an external power source or a control device into the connector on the driver part side. When the current controlled by the driver unit is applied to the stator coil constituting the motor unit (sensorless brushless DC motor), the rotor is rotated by the rotating magnetic field, and the pump unit (pump operating unit) is operated.

JP 2004-353537 A

  In such an electric pump, it is necessary to ground the substrate of the driver unit in order to generate a malfunction of the driver unit and to ensure safety. Then, in addition to the harness for power supply and control to the driver unit, ground wiring for grounding the board is required, which leads to complicated wiring. Moreover, when the number of wirings increases, the number of terminals of the connector also increases, which may increase the size of the connector. Such a problem becomes more serious in the case of a high-power electric pump because a plurality of power supply harnesses are required, and problems such as an increase in cost of the electric pump and deterioration in mountability may occur.

  The present invention has been made in view of the above problems, and an object thereof is to provide an electric pump that eliminates the need for ground wiring for a substrate of a driver section.

A first characteristic configuration of the electric pump according to the present invention includes a pump unit, a motor unit that drives the pump unit, a conductive motor housing that houses at least the motor unit, and a driver unit that controls the motor unit. A connecting member for electrically connecting the substrate and the motor housing, wherein the substrate of the driver portion is grounded via the motor housing, and a resin pedestal for attaching the substrate is fixed to the motor housing. Is formed integrally with the pedestal, and the pedestal and the board have a notch used to fix the fixing part of the connecting member to the motor housing from the side of the board .

  According to this configuration, since the substrate of the driver unit is grounded via the motor housing, the ground wiring for the substrate and the terminal for the wiring are not necessary. Therefore, simplification of wiring and miniaturization of the connector can be realized, which is advantageous in terms of cost. In addition, when electricity flows through the motor housing, it is easy to remove electrical noise generated in the motor unit.

Furthermore, according to this configuration, since the connection member is formed integrally with the pedestal, the substrate and the connection member can be easily connected when the substrate is fixed to the pedestal. The manufacturing efficiency of the driver ASSY is improved. Further, since the pedestal is made of resin, the connecting member can be formed integrally with the pedestal by insert molding, and the process of assembling the connecting member to the pedestal is not necessary.

The second characteristic configuration is that a body portion between one end portion fixed to the motor housing and the other end portion connected to the substrate is fixed by the pedestal among the connection members.

  When vibration generated in the motor unit, pump unit, etc. is transmitted to the connection member, the load concentrates on both ends of the connection member fixed to the motor housing and the board, and the connection member comes off from the motor housing or the board or is damaged. There is a risk of doing. In particular, at the end of the connection member fixed to the substrate, vibration is amplified in accordance with the height of the connection member.

  Therefore, as in this configuration, if the body portion of the connection member is fixed by the pedestal, vibration generated in the connection member due to vibration from the motor unit, the pump unit, or the like can be reduced. Therefore, the load on both ends of the connecting member can be reduced. Also, by fixing the body part of the connection member with the pedestal, the amplification of vibration according to the height of the connection member can be reduced, and the load on the end of the connection member fixed to the substrate is reduced. Can be reduced.

A third characteristic configuration is that the motor housing and a conductive pump housing that accommodates the pump portion are fixed using conductive bolts.

  According to this configuration, if either the motor housing or the pump housing is grounded, the board of the driver unit can be grounded, so that the degree of freedom in assembling the electric pump is increased. Further, if configured in this way, even if a non-conductive member exists between the motor housing and the pump housing, the substrate can be reliably grounded.

It is sectional drawing which shows embodiment of the electric pump which concerns on this invention. It is an exploded view which shows the structure of a driver part. It is a perspective view which shows the fixed state of a connection member. It is explanatory drawing which shows the flow of the electricity in an electric pump.

  Hereinafter, embodiments of an electric pump according to the present invention will be described with reference to the drawings. As shown in FIG. 1, the electric pump 1 according to the present embodiment includes a pump unit 2, a motor unit 3 that drives the pump unit 2, and a driver unit 4 that controls the motor unit 3. . The electric pump 1 is attached to a vehicle engine unit (not shown) on the pump unit 2 side, and functions as a water pump for circulating engine cooling water.

  The pump housing 21 that houses the pump unit 2 is made of a conductive material, and is formed with a suction port 21a for sucking cooling water from the engine unit and a discharge port 21b for sending cooling water to the engine unit. Yes. The suction port 21a and the discharge port 21b communicate with an impeller chamber 21c formed inside the pump housing 21, respectively. An impeller 22 is accommodated in the impeller chamber 21c, and when the impeller 22 rotates, cooling water is sucked into the impeller chamber 21c from the suction port 21a, and cooling water is discharged from the impeller chamber 21c to the discharge port 21b.

  The motor housing 31 that houses the motor unit 3 is made of an aluminum material. Since the aluminum material has conductivity, it can be used to ground the substrate 42 of the driver unit 4. Further, since the aluminum material also has thermal conductivity, the heat generated in the motor unit 3 can be easily radiated through the motor housing 31. However, the motor housing 31 can be made of other materials as long as the material has a certain degree of conductivity and thermal conductivity.

  Inside the motor housing 31, a stator 32, a rotor 36 disposed radially inside the stator 32, and a support shaft 38 that is a rotation support shaft of the rotor 36 are provided. The stator 32 is provided with a coil 33, and the stator 32 and the coil 33 are cast by a stator housing 35 made of resin.

  A terminal 34 for electrically connecting the coil 33 and the substrate 42 of the driver unit 4 protrudes from the opening 31 b formed in the end surface 31 a of the motor housing 31 toward the drive unit 4. Further, on the inner side of the end surface 31a of the motor housing 31, there is formed an annular groove heat radiating portion 31c through which the engine coolant flowing into the motor housing 31 from the impeller chamber 21c can flow. Therefore, since the heat generated in the driver unit 4 passes through the motor housing 31 and is recovered by the cooling water in the heat radiating unit 31c, an increase in the temperature of the driver unit 4 can be suppressed.

  The rotor 36 is formed integrally with one end of a rotating member 37 formed of resin, and when the coil 33 is energized and a rotating magnetic field is generated in the stator 32, the rotor 36 and the rotating member 37 are supported by the support shaft 38. As a rotating spindle. When the rotating member 37 rotates, the impeller 22 formed at the other end of the rotating member 37 rotates, and engine cooling water is drawn into the impeller chamber 21c from the suction port 21a, and from the impeller chamber 21c to the discharge port 21b. Cooling water is discharged, and the pump unit 2 functions as a water pump.

  The driver unit 4 includes a driver assembly 48 including a substrate 42 and a resin base 43 in a space defined by the end surface 31 a of the motor housing 31 and the cover 41. The pedestal 43 is formed with a connector portion 43a, and the connector portion 43a is provided with a connector terminal 46 for electrically connecting a power source (not shown) and the substrate 42. Of the connector terminals 46, terminal portions 46 a protruding from the base 43 are connected to the substrate 42.

  As shown in FIGS. 2 and 3, a connecting member 44 is integrally provided on the pedestal 43. Of the connecting member 44, a bifurcated terminal portion 44 a (“other end portion” in the present invention) connected to the substrate 42, and a fixing portion 44 b (“one end portion” in the present invention) fixed to the motor housing 31. The body part 44c between the two is embedded in the pedestal 43 by insert molding.

  Similar to the connection member 44, a U-shaped terminal 47 is embedded in the pedestal 43 by insert molding. One end portion of the U-shaped terminal 47 is configured as a terminal portion 47 a connected to the substrate 42, and the other end portion is configured as a connection portion 47 b having a convex portion 47 c that contacts the terminal 34 when assembled. Further, the pedestal 43 is formed with an accommodation space 43 b for accommodating the FET 45 and a through hole 43 c for inserting the terminal 34. The FET 45 has a terminal portion 45 a for connecting to the substrate 42.

  In addition to the FET 45, various electronic elements are disposed on the substrate 42. Various electronic elements may be arranged directly on the substrate 42, or a main body may be provided on the pedestal 43 like the FET 45 and connected to the substrate 42 by a terminal portion. Here, illustration and description of electronic elements other than the FET 45 are omitted.

  The substrate 42 is formed with terminal holes 42a to 42d through which the terminal portion 44a of the connection member 44, the terminal portion 45a of the FET 45, the terminal portion 46a of the connector terminal 46, and the terminal portion 47a of the U-shaped terminal 47 are inserted. Has been. When assembling the driver ASSY 48, first, the board 42 is screwed to the protruding fixing portion 43d provided on the base 43. Next, the terminal portions 44 a to 47 a are inserted into the corresponding terminal holes 42 a to 42 d and soldered to the substrate 42. Thus, since the soldering of the terminal portion 44a of the connecting member 44 to the substrate 42 can be performed simultaneously with the soldering of the other terminal portions 45a to 47a, the driver ASSY 48 can be manufactured efficiently.

  The driver assembly 48 assembled as described above is fixed to the motor housing 31 in a state where the terminal 34 is inserted into the through hole 43 c of the base 43. As fixing means, suitable means such as bolt fastening, welding, and adhesion can be selected, but it is desirable that the back surface of the FET 45 be adhered to the motor housing 31. By bonding the back surface of the FET 45 to the motor housing 31, heat generated from the FET 45 is directly transmitted to the motor housing 31, which is advantageous in terms of heat dissipation of the driver unit 4. Furthermore, in the present embodiment, the heat dissipation is further improved by disposing the FET 45 in the vicinity of the heat dissipation portion 31 c of the motor housing 31.

  When the driver ASSY 48 is fixed to the motor housing 31, the terminal 34 comes into contact with the convex portion 47 c of the U-shaped terminal 47, and the coil 33 can be energized from the substrate 42. As described above, in order to realize the electrical connection between the substrate 42 and the coil 33, it is only necessary to insert the terminal 34 into the through hole 43c, and the soldering is unnecessary, so that the manufacturing process is simplified. Can be achieved.

  After the driver assembly 48 is fixed to the motor housing 31, the fixing portion 44 b of the connection member 44 is screwed to the motor housing 31. As shown in FIG. 3, the substrate 42 and the pedestal 43 are formed with notches 42e and 43e for inserting a screwing tool, respectively. By screwing the fixing portion 44 b of the connection member 44 to the motor housing 31, the connection member 44 and the motor housing 31 can be reliably brought into contact with each other, so that the substrate 42 is more reliably grounded via the motor housing 31. be able to. Further, by ensuring the contact between the connecting member 44 and the motor housing 31, there is an effect that the heat of the substrate 42 can be radiated to the motor housing 31 side via the connecting member 44. Finally, the cover 41 is provided to complete the driver unit 4.

  In the present embodiment, as shown in FIG. 3, the body portion 44 c of the connection member 44 is fixed in a state of being embedded in the pedestal 43. Therefore, the vibration generated in the connection member 44 due to vibrations from the pump unit 2, the motor unit 3, or the engine unit (not shown) can be reduced. As a result, the load on both ends 44a and 44b of the connection member 44 is reduced. Can be reduced. In particular, by fixing the body portion 44c of the connection member 44 with the pedestal 43, vibration amplification in the connection member 44 can be reduced, so that the load on the terminal portion 44a is reduced.

  As shown in FIG. 1, the pump housing 21 and the motor housing 31 are fastened together with conductive bolts 51 with a flange portion 35 a of a resin stator housing 35 interposed therebetween. According to this configuration, even if the non-conductive stator housing 35 exists between the pump housing 21 and the motor housing 31, as shown by the broken line in FIG. 31, the bolt 51, the pump housing 21, and the engine unit can be grounded.

  Further, in the present embodiment, a metal sleeve material 39 is provided at the bolt fastening portion of the flange portion 35 a of the stator housing 35. Therefore, when the sleeve material 39 comes into contact with the pump housing 21 and the motor housing 31, an electrical connection between the pump housing 21 and the motor housing 31 is established via the sleeve material 39 as shown by a one-dot chain line in FIG. As a result, the grounding of the substrate 42 can be realized more reliably.

Other Embodiment
(1) In the above embodiment, the electrical connection between the substrate 42 and the motor housing 31 is realized by the connection member 44 which is a separate member. However, the substrate 42 and the motor housing 31 can be brought into direct contact without providing a separate member, and a screw member for fixing the substrate 42 to the motor housing 31 can be used for electrical connection. is there.

  (2) In the above embodiment, the pump housing 21 and the motor housing 31 are configured separately, and are fixed by bolts 51, whereby the substrate 42 is interposed via the engine portion or the like existing on the pump housing 21 side. Was to be grounded. However, the pump housing 21 or the motor housing 31 may be directly grounded. Further, the pump housing 21 and the motor housing 31 can be integrally configured.

  The electric pump according to the present invention can be applied not only to a type of pump using an impeller, but also to other types of pumps such as a positive displacement pump. The electric pump can also be used as a pump other than a water pump for a vehicle engine.

DESCRIPTION OF SYMBOLS 1 Electric pump 2 Pump part 3 Motor part 4 Driver part 21 Pump housing 31 Motor housing 42 Board | substrate 43 Base 44 Connection member 44a Terminal part (other end part)
44b Fixed part (one end)
44c fuselage 51 bolt

Claims (3)

A pump section;
A motor unit for driving the pump unit;
A conductive motor housing that houses at least the motor section;
A driver unit for controlling the motor unit,
The driver part substrate is grounded via the motor housing ,
A resin pedestal for mounting the substrate is fixed to the motor housing,
A connecting member for electrically connecting the substrate and the motor housing is formed integrally with the pedestal,
The pedestal and the board are electric pumps having a notch used for fixing the fixing part of the connection member to the motor housing from the board side . Wherein one of the connecting members, the body portion between the other end portion connected to the substrate and one end portion fixed to the motor housing, the electric pump according to claim 1 which is secured by the base. The electric pump according to claim 1 or 2 , wherein the motor housing and a conductive pump housing that houses the pump portion are fixed using conductive bolts.

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