JP2024007201A - current sensor - Google Patents

Abstract

[Problem] To provide a current sensor that can improve assembly while ensuring airtightness. [Solution] The current sensor 1 includes a circuit board 8 that is electrically connected to a sensor section, a housing 6 that houses the circuit board 8 in an installation opening 64a, a potting material 9 filled in the installation opening 64a, and a cover member 10 that closes the installation opening 64a, and the cover member 10 has an anchor portion 12 that is formed to protrude toward the potting material 9 side and includes a hook-shaped portion 12b that is embedded in the potting material 9. With this configuration, the current sensor 1 has the effect of improving assembly while ensuring airtightness. [Selected Figure] Figure 9

Description

TECHNICAL FIELD The present invention relates to a current sensor.

As a technique related to a conventional current sensor, for example, Patent Document 1 discloses a current detection device that detects a current flowing into a harness through a battery terminal. The current detection device includes a case having a recess that accommodates a circuit board, and a lid that closes an opening of the recess.

Japanese Patent Application Publication No. 2011-117853

By the way, in the above-mentioned current detection device, for example, the case and the lid are bonded with adhesive in order to ensure that the case housing the circuit board and the lid are in close contact with each other. There is room for further improvement.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a current sensor that can improve assemblability while ensuring airtightness.

In order to achieve the above object, the current sensor of the present invention includes: a sensor section that detects current; a circuit board electrically connected to the sensor section; a housing that accommodates the circuit board in an installation opening; The opening includes a potting material filled in the opening and a cover member that closes the installation opening, the cover member being formed to protrude toward the potting material and having a hook-shaped part embedded in the potting material. It has an anchor part including.

The current sensor according to the present invention has the advantage of being able to improve assemblability while ensuring hermeticity.

FIG. 1 is a circuit diagram showing a schematic configuration of a current sensor according to an embodiment. FIG. 2 is a perspective view showing a schematic configuration of the current sensor according to the embodiment. FIG. 3 is an exploded perspective view showing a schematic configuration of the current sensor according to the embodiment. FIG. 4 is a partially exploded perspective view including an installation opening of the current sensor according to the embodiment. FIG. 5 is a partially exploded perspective view including a circuit board of the current sensor according to the embodiment. FIG. 6 is a partially exploded perspective view including a potting material of the current sensor according to the embodiment. FIG. 7 is a partially exploded perspective view including a cover member of the current sensor according to the embodiment. FIG. 8 is a perspective view showing a schematic configuration of the cover member of the current sensor according to the embodiment. FIG. 9 is a schematic cross-sectional view including a cover member of the current sensor according to the embodiment. FIG. 10 is a perspective view showing a schematic configuration of a cover member of a current sensor according to a modification. FIG. 11 is a schematic cross-sectional view including a cover member of a current sensor according to a modification.

Embodiments according to the present invention will be described in detail below based on the drawings. Note that the present invention is not limited to this embodiment. Furthermore, the constituent elements in the embodiments described below include those that can be easily replaced by those skilled in the art, or those that are substantially the same.

In addition, in the following explanation, among the first direction, second direction, and third direction that intersect with each other, the first direction will be referred to as the "axial direction X", and the second direction will be referred to as the "first width direction Y". Okay, the third direction is called the "second width direction Z." Here, the axial direction X, the first width direction Y, and the second width direction Z are substantially perpendicular to each other. The axial direction X typically corresponds to the direction along the central axis C of the battery post (see FIG. 2, etc.) where the current sensor is provided, the height direction of the battery, and the like. The first width direction Y typically corresponds to a direction in which the battery terminal portion and the sensor portion are lined up. The second width direction Z typically corresponds to the tightening direction of the battery terminal portion. Typically, when the current sensor is installed in a vehicle and the vehicle is located on a horizontal plane, the axial direction X is along the vertical direction, and the first width direction Y and the second width direction Z are along the horizontal direction. Unless otherwise specified, each direction used in the following description represents a direction in which each part is assembled with each other.

[Embodiment]
The current sensor 1 of the present embodiment shown in FIGS. 1, 2, and 3 is typically a sensor for measuring the charging and discharging current of a battery B mounted on a vehicle V, and the current sensor 1 of the present embodiment shown in FIGS. (only a part of which is shown in the figure) is applied to a power supply system S of a vehicle V. Here, battery B is mounted on vehicle V as a power storage device. In the battery B, a battery post P is provided on one surface of a battery casing Ba that accommodates battery fluid and various components, typically a post installation surface Bb located on the vertically upper side. The battery post P is disposed so that the center axis C is along the vertical direction, here, the axial direction X, and extends in a columnar shape along the axial direction X. A total of two battery posts P are provided in one battery B, one as a positive electrode (plus (+) electrode) and one as a negative electrode (minus (-) electrode) (only one side is shown in Figure 2, etc.). (Illustrated).

The current sensor 1 of this embodiment has a battery mounting structure, and here constitutes a battery terminal-integrated sensor integrated with a battery terminal (battery terminal portion 2). The current sensor 1 constituting the battery terminal integrated sensor is fastened to the battery post P configured as described above. As an example, the current sensor 1 of this embodiment is fastened to a battery post P on the negative electrode side of a battery B and is electrically connected to the battery post P, and connects the battery B, the generator G, the vehicle load part L, and the ground part ( (vehicle body, etc.) and GND, etc., and detects the current flowing between the battery post P and these.

The current sensor 1 of this embodiment is a so-called shunt type current sensor. That is, the current sensor 1 applies a current to the shunt resistor 40 and measures the current value based on the voltage drop when the current is applied and the resistance value of the shunt resistor 40 using Ohm's law. Typically, the current sensor 1 amplifies and outputs a voltage (detected voltage) generated across the shunt resistor 40 according to the current flowing through the shunt resistor 40 using an amplifier AP, and outputs the amplified voltage based on the output of the amplifier AP. The current flowing through the shunt resistor 40 is detected.

In the current sensor 1 of this embodiment, the shunt resistor 40 and the circuit board 8 are built into the housing 6, and a predetermined shape is added to the cover member 10 that closes the installation opening 64a. This improves ease of assembly while ensuring the same. Hereinafter, each configuration of the current sensor 1 will be explained in detail with reference to each figure.

Specifically, as shown in FIGS. 2 and 3, the current sensor 1 includes a battery terminal section 2, a terminal connection section 3, a sensor section 4, a stud bolt 5, a housing 6, and an output terminal 7. , a circuit board 8, a potting material 9, a cover member 10, and a tightening mechanism 50.

The battery terminal section 2, the terminal connection section 3, and the sensor section 4 together constitute a busbar assembly BA. In other words, the current sensor 1 can be said to include the bus bar assembly BA. Busbar assembly BA includes a BT busbar 20, a GND busbar 30, and a shunt resistor 40, which are integrally configured. The BT bus bar 20 is a first bus bar that constitutes the battery terminal section 2. The GND bus bar 30 is a second bus bar that constitutes the terminal connection section 3. The BT bus bar 20 and the GND bus bar 30 form a pair of conductive bus bars in the current sensor 1. The shunt resistor 40 is a current detection resistor that constitutes the sensor section 4, and is electrically connected across the pair of bus bars, that is, the BT bus bar 20 and the GND bus bar 30.

The BT bus bar 20, the GND bus bar 30, and the shunt resistor 40 are each plate-shaped metal conductors having electrical conductivity. The BT bus bar 20, the GND bus bar 30, and the shunt resistor 40 are formed into shapes corresponding to the battery terminal section 2, terminal connection section 3, and sensor section 4, respectively, by being subjected to various processing. The BT bus bar 20 and the GND bus bar 30 are made of a metal with good conductivity, such as copper (Cu) or a copper alloy. On the other hand, the shunt resistor 40 is made of a different metal than the BT bus bar 20 and the GND bus bar 30, such as copper-manganese-nickel (Cu-Mn-Ni) whose resistance value does not easily fluctuate depending on temperature and has good temperature characteristics. It is composed of alloys, copper-nickel (Cu-Ni) alloys, nickel-chromium (Ni-Cr) alloys, etc.

The battery terminal portion 2 is a portion that has conductivity and is fastened to the battery post P, and is constituted by the above-mentioned BT bus bar 20. The battery terminal section 2 includes a main body section 21 and an electrode section 22. The main body part 21 is the main part fastened to the battery post P. The electrode portion 22 is a portion electrically connected to the shunt resistor 40 that constitutes the sensor portion 4 . The battery terminal section 2 is formed by integrally forming the main body section 21 and the electrode section 22 by, for example, subjecting the BT bus bar 20 to a press bending process.

The main body portion 21 is constructed by stacking substantially parallel metal plates folded back into a substantially U-shape. The main body part 21 is configured such that the battery post P is inserted into the post insertion hole 21a along the axial direction X, and the part where the slit 21b is formed is tightened by the tightening mechanism 50. It is connected and conductive. The electrode part 22 is formed by a plate-shaped sheet metal folded back into a substantially L-shape, which is positioned in line with the main body part 21 along the first width direction Y and is connected to the main body part 21. 21 and are electrically connected. A shunt resistor 40 is connected to an end of the electrode portion 22 on the side opposite to the main body portion 21 side in the first width direction Y. The electrode part 22 has a detection terminal part 22a that protrudes in a tab shape (column shape) toward one side along the axial direction X, here, the side opposite to the post installation surface Bb side. The detection terminal section 22a is a voltage detection terminal that outputs an output for detecting the battery voltage that is the voltage of the battery B.

The terminal connection part 3 is a part that is electrically conductive and is electrically connected to a connection terminal (not shown) provided at the end of an electric wire (for example, a ground wire) on the grounding part GND side, for example. It is constituted by a GND bus bar 30. The terminal connection part 3 is located side by side with the battery terminal part 2 along the first width direction Y at an interval, and includes a fastening part 31 and an electrode part 32. The fastening portion 31 is a portion electrically connected to the stud bolt 5 and a connection terminal (not shown). The electrode portion 32 is a portion electrically connected to the shunt resistor 40 that constitutes the sensor portion 4 . The terminal connection portion 3 is formed by integrally forming a fastening portion 31 and an electrode portion 32, each of which is formed into a plate shape, by subjecting the GND bus bar 30 to a press bending process or the like.

The fastening portion 31 has a plate thickness direction along the axial direction X, and extends along the first width direction Y and the second width direction Z. The fastening portion 31 is formed with a bolt insertion hole 31a into which the shaft portion 5a of the stud bolt 5 is inserted. The electrode part 32 has a plate thickness direction along the second width direction Z, and extends along the axial direction X and the first width direction Y, and is located on the other side of the axial direction It is connected to the fastening part 31 on the Bb side, and is thereby electrically connected integrally with the fastening part 31. A shunt resistor 40 is connected to an end of the electrode portion 32 on the battery terminal portion 2 side in the first width direction Y.

The sensor section 4 is a section located along the first width direction Y along with the battery terminal section 2, electrically connected to the battery terminal section 2, and detects current. The sensor section 4 is located between the battery terminal section 2 and the terminal connection section 3 along the first width direction Y. The sensor section 4 of this embodiment constitutes a shunt-type current sensor section, and includes the above-mentioned shunt resistor 40.

The shunt resistor 40 is formed into a plate shape and constitutes the main part of the resistor. The shunt resistor 40 is formed into a substantially rectangular plate shape, and has a thickness direction along the second width direction Z, and extends along the axial direction X and the first width direction Y. The shunt resistor 40 is electrically connected between the BT bus bar 20 that constitutes the battery terminal section 2 and the GND bus bar 30 that constitutes the terminal connection section 3 . Here, the shunt resistor 40 is arranged such that the end face of the electrode part 22 of the BT bus bar 20 and the end face of the electrode part 32 of the GND bus bar 30 are located opposite to each other along the first width direction Y. portion 32 and is joined to the electrode portion 22 and the electrode portion 32. The shunt resistor 40 has a pair of detection terminal portions 40a and 40b that protrude in a tab shape (column shape) toward one side along the axial direction X, here, the opposite side from the post installation surface Bb side. . The detection terminal sections 40a and 40b are current detection terminals that output to detect the current flowing through the shunt resistor 40, in other words, the charging and discharging current of the battery B, and are provided as a pair.

The bus bar assembly BA, which is constructed by integrating the battery terminal section 2, the terminal connection section 3, and the sensor section 4, has been described above.

The stud bolt 5 is a fastening member having a shaft portion 5a inserted into the bolt insertion hole 31a of the terminal connection portion 3 along the axial direction X. The stud bolt 5 is fastened by inserting the shaft portion 5a into the bolt insertion hole 31a along the axial direction X and screwing a nut (not shown) onto the shaft portion 5a with the connecting terminal assembled. The portion 31 and the connecting terminal are fastened to establish a conductive connection.

The housing 6 is a protective member that has insulation properties and houses and protects the sensor section 4 (shunt resistor 40), the output terminal 7, the circuit board 8, and the like. The housing 6 is made of, for example, a resin that is insulating and has high heat resistance. The housing 6 is integrally formed with the bus bar assembly BA, the stud bolt 5, the output terminal 7, etc. by insert molding or the like, for example. Thereafter, the circuit board 8 is assembled inside the housing 6, and then the potting material 9 and the cover member 10 are provided.

For example, in the busbar assembly BA, a BT busbar 20, a GND busbar 30, and a shunt resistor 40 are integrated, and a stud bolt 5 is assembled into a bolt insertion hole 31a, and an output terminal is inserted into a mold for insert molding of a housing 6. It is inserted (set) together with 7. Then, the housing 6 is formed integrally with the bus bar assembly BA, the stud bolt 5, the output terminal 7, etc. by injecting an insulating resin into this mold and molding it.

The housing 6 houses the bus bar assembly BA, the stud bolt 5, and the output terminal 7 inside, and exposes some of these to the outside of the housing 6. Specifically, the housing 6 includes a sensor cover section 61, a bolt holding section 62, a connector housing section 63, and a board cover section 64, which are integrally formed.

The sensor cover part 61 is a part in which the shunt resistor 40 constituting the sensor part 4 is embedded, and covers and protects the shunt resistor 40 . Here, the sensor cover part 61 is embedded with the shunt resistor 40 as well as the electrode part 22 and the electrode part 32 to cover and protect them. The bolt holding portion 62 is a portion in which the stud bolt 5 inserted into the bolt insertion hole 31a of the terminal connection portion 3 is buried and held therein. Here, the bolt holding part 62 holds the fastening part 31 and the stud bolt 5 while exposing one surface of the fastening part 31 and the shaft part 5a of the stud bolt 5 along one side in the axial direction X. do. The connector housing part 63 is a part that constitutes the connector part CN together with the output terminal 7. The connector housing portion 63 is formed in a cylindrical shape that is open on one side in the first width direction Y, and holds the output terminal 7 so that the end portion of the output terminal 7 is exposed inside. The board cover part 64 is a part that accommodates the circuit board 8 therein and covers and protects the circuit board 8. The board cover part 64 has an installation opening 64a for assembling the circuit board 8 inside the board cover part 64 after the housing 6 is molded. The installation opening 64a is formed as a substantially rectangular space in accordance with the shape of the circuit board 8, and opens toward one side in the axial direction X, here, the side opposite to the post installation surface Bb. As shown in FIG. 4, the installation opening 64a exposes the ends of the detection terminal section 22a, the detection terminal sections 40a and 40b, and the output terminal 7. The housing 6 accommodates the circuit board 8 in the installation opening 64a to cover and protect the circuit board 8 therein.

The output terminal 7 is a terminal that is electrically connected to the circuit board 8 and outputs the sensor output detected by the sensor section 4 to the outside. Here, the output terminal 7 is constituted by a pair of bent terminals that are electrically conductive and formed in a substantially L-shape. As described above, the output terminal 7 is embedded and integrated inside the connector housing part 63 by insert molding, and together with the connector housing part 63 constitutes the connector part CN for sensor output.

The circuit board 8 has electronic components mounted thereon to form an electronic circuit. The circuit board 8 is electrically connected to the sensor section 4 and the like. The circuit board 8 is configured by, for example, a so-called printed circuit board (PCB). Here, the circuit board 8 is electrically connected to the detection terminal section 22a of the battery terminal section 2, the detection terminal sections 40a and 40b of the shunt resistor 40, and the output terminal 7. For example, the circuit board 8 is mounted with electronic components that implement various functions, such as the above-mentioned amplifier AP. The voltage (potential difference) generated at both ends of the shunt resistor 40 is input to the circuit board 8 via the pair of detection terminals 40a and 40b connected as described above. Furthermore, the voltage (potential) of the negative electrode of the battery B is input to the circuit board 8 via the detection terminal section 22a connected as described above. The circuit board 8 may output these input voltages (detected voltages) themselves to the host ECU via the output terminal 7 (analog output). In this case, the host ECU calculates the current value and battery voltage value based on the input detection voltage. In addition, the circuit board 8 is equipped with a microcomputer as an electronic component, and the microcomputer calculates a current value and a battery voltage value based on these input voltages (detected voltage), and the calculated current value and battery voltage value are calculated by the microcomputer based on the input voltages (detected voltages). A detection signal representing the voltage value may be output to the upper ECU via the output terminal 7 (digital output).

The circuit board 8 configured as described above is assembled into the installation opening 64a described above after the housing 6 is molded, as shown in FIG. In this case, the circuit board 8 is inserted into the installation opening 64a while inserting the detection terminal portion 22a, the detection terminal portions 40a and 40b, and the output terminal 7 exposed along the axial direction X into the through hole. 64a. Thereafter, the circuit board 8 is electrically connected to the detection terminal section 22a, the detection terminal sections 40a and 40b, and the output terminal 7 by soldering or the like.

The potting material 9 is a filler filled in the installation opening 64a. The potting material 9 is made of, for example, a resin having insulation properties and high adhesiveness. As shown in FIG. 6, the potting material 9 is filled into the installation opening 64a after the circuit board 8 is assembled into the installation opening 64a. The potting material 9 is densely filled in the installation opening 64a and hardens to adhere to the inner wall surface of the installation opening 64a, and the potting material 9 adheres to the inner wall surface of the installation opening 64a, the output terminal 7, the entire surface of the circuit board 8, the detection terminal parts 22a, 40a, 40b etc. The potting material 9 then closes the opening on one side of the installation opening 64a in the axial direction X (see also FIG. 9, etc.). Thereby, the potting material 9 can seal and seal the installation opening 64a, prevent dust, water, etc. from entering into the installation opening 64a, and ensure dustproof performance and waterproof performance. .

The cover member 10 is a lid member that closes the installation opening 64a. The cover member 10 is formed into a substantially rectangular plate shape having a partially protruding shape to match the shape of the installation opening 64a. The cover member 10 closes the installation opening 64a filled with the potting material 9, as shown in FIG. Thereby, the cover member 10 covers the potting material 9 and prevents the potting material 9 from being exposed to the outside.

As shown in FIGS. 8 and 9, the cover member 10 of this embodiment has an anchor part 12 added thereto, and when the cover member 10 closes the installation opening 64a, a part of this anchor part 12 is attached. It has a structure in which it is fixed by being embedded in the potting material 9.

Specifically, the cover member 10 has a main body portion 11 and an anchor portion 12, which are integrally formed. The cover member 10 is made of a resin or the like that has insulation properties and high heat resistance.

The main body portion 11 is the main portion that closes the installation opening 64a. As described above, the main body portion 11 is formed into a substantially rectangular plate shape having a partially protruding shape in accordance with the shape of the installation opening 64a. The main body portion 11 has a thickness direction along the axial direction X, and extends along the first width direction Y and the second width direction Z. Here, the main body part 11 has a stepped shape part 11a attached to the peripheral edge thereof in order to prevent the main body part 11 from being misaligned with respect to the installation opening 64a while the opening of the installation opening 64a is closed. The main body portion 11 closes the opening of the installation opening 64a by positioning the end of the wall forming the installation opening 64a against the stepped portion 11a. is positioned at the appropriate position.

The anchor portion 12 is a portion that is formed to protrude from the main body portion 11 toward the potting material 9 side along the axial direction X, and is at least partially embedded in the potting material 9. The anchor part 12 is configured to include a hook-shaped part 12b as a part embedded in the potting material 9. The hook-shaped portion 12b is embedded in the potting material 9 and serves as a hook to prevent the anchor portion 12 from coming off the potting material 9. Here, the hook-shaped portion 12b is formed at the protruding tip of the anchor portion 12 that is formed to protrude from the main body portion 11 along the axial direction X.

More specifically, the anchor portion 12 of this embodiment includes a pair of columnar portions 12a and a hook-shaped portion 12b. A pair of columnar parts 12a are located opposite to each other with an interval between them, and each extends along the protruding direction of the anchor part 12, which is the axial direction X here. The pair of columnar parts 12a are both formed in a substantially rectangular column shape. The hook-shaped portion 12b is formed into a beam shape that connects the pair of columnar portions 12a along the direction intersecting the axial direction X (protrusion direction), here, the first width direction Y or the second width direction Z. be done. That is, here, the hook-shaped portion 12b constitutes a beam-shaped portion that interconnects the protruding tips of the pair of columnar portions 12a. The hook-shaped portion 12b is located across the pair of columnar portions 12a, and a portion extending along a direction intersecting the axial direction X becomes a hook portion for the potting material 9.

Here, in the cover member 10, a plurality of anchor portions 12 configured as described above are provided evenly along the wall portion forming the installation opening 64a, in this case five anchor portions. As described above, each anchor portion 12 includes a pair of columnar portions 12a and a hook-shaped portion 12b that connects the pair of columnar portions 12a.

After the potting material 9 is filled into the installation opening 64a, the cover member 10 configured as described above is assembled to the housing 6 in a manner that blocks the installation opening 64a while the potting material 9 is not yet hardened. It will be done. The cover member 10 is positioned at an appropriate position relative to the installation opening 64a by abutting the end of the wall forming the installation opening 64a against the stepped portion 11a of the main body 11. It is assembled into the housing 6. In this state, the cover member 10 is in a state where each anchor portion 12 is inserted into the potting material 9 along the axial direction X, and the hook-shaped portion 12b is located within the potting material 9. Thereafter, the cover member 10 is in a state where the hook-shaped portion 12b is embedded in the potting material 9 as the potting material 9 hardens. In this state, the hook-shaped portion 12b of the cover member 10 is hooked onto the hardened potting material 9 and becomes anchored, and as a result, the cover member 10 is maintained in a fixed state with respect to the housing 6 and the potting material 9. Thereby, the cover member 10 can maintain a state in which it covers the potting material 9 filled in the installation opening 64a and prevents the potting material 9 from being exposed to the outside.

In the current sensor 1 configured as described above, when the battery post P is inserted into the post insertion hole 21a of the battery terminal portion 2, the portion where the slit 21b is formed is tightened by the tightening mechanism 50. is fastened to the battery post P. Here, as an example, the tightening mechanism 50 includes a bolt 51, a nut 52, and a washer 53. In the tightening mechanism 50, by tightening the nut 52 along the second width direction Z, the head portion of the bolt 51 and the washer 53 cooperate to tighten the above-mentioned portion of the battery terminal portion 2 in the second width direction Z. Generates a tightening force along the As a result, the tightening mechanism 50 can reduce the diameter of the post insertion hole 21a and fasten the battery terminal portion 2 to the battery post P to establish electrical continuity. Then, in the current sensor 1, the connecting terminal is assembled to the shaft portion 5a of the stud bolt 5 and a nut is screwed, so that the connecting terminal is fastened to the shaft portion 5a. are electrically connected.

In this state, the current sensor 1 detects current according to the output from the detection terminal portions 40a and 40b of the shunt resistor 40. That is, in the current sensor 1, the sensor section 4 detects the current flowing between the connection terminal and the battery post P, and outputs the detected sensor output to the host ECU via the connector section CN. The current sensor 1 amplifies and outputs a voltage (detection voltage) generated across the shunt resistor 40 according to the current flowing through the shunt resistor 40 using an amplifier AP, and outputs the amplified voltage (detection voltage) generated across the shunt resistor 40 based on the output of the amplifier AP. Detect current. In this case, the entity that actually calculates the current value may be a microcomputer mounted on the circuit board 8, or may be a host ECU to which the sensor output is output. Further, the current sensor 1 can also detect the battery voltage according to the output from the detection terminal section 22a of the battery terminal section 2.

The cover member 10 of the present embodiment is arranged on the side opposite to the post installation surface Bb with respect to the axial direction The opening of the installation opening 64a that opens toward the opposite side from the post installation surface Bb is closed.

Here, the current sensor 1 allows a gap to be formed between the surface of the potting material 9 and the inner surface of the main body part 11 of the cover member 10, for example, for tolerance management, but the present invention is not limited to this. First, the surface of the potting material 9 and the inner surface of the main body portion 11 may be in close contact with each other.

The current sensor 1 described above can detect current using the sensor section 4. In this configuration, the current sensor 1 seals and seals the installation opening 64a that accommodates the circuit board 8 electrically connected to the sensor section 4 with the potting material 9, thereby preventing dust from entering the installation opening 64a. It can prevent water from entering and ensure dustproof and waterproof performance. Further, the current sensor 1 can prevent the potting material 9 from being exposed to the outside by blocking the installation opening 64a filled with the potting material 9 with the cover member 10. For example, the potting material 9 can be prevented from being exposed to the outside. It is possible to prevent foreign matter from interfering with the

In this case, the current sensor 1 is in a state where the hook-shaped portion 12b of the anchor portion 12 of the cover member 10 is embedded in the potting material 9 filled in the installation opening 64a, and is hooked and anchored by the potting material 9. It becomes. Thereby, in the current sensor 1, the cover member 10 can be maintained in a fixed state with respect to the housing 6 and the potting material 9, and covers the potting material 9 filled in the installation opening 64a. 9 can be maintained in a state where exposure to the outside is prevented. As a result, the current sensor 1 can fix the cover member 10 to the housing 6 and the potting material 9 without using equipment for gluing or welding the cover member 10 to the housing 6, for example. . Furthermore, the current sensor 1 can also eliminate the need for strict process control, quality control, etc. associated with adhesion or welding, for example. That is, in the current sensor 1, with the above configuration, the cover member 10 can be easily assembled to the housing 6, so that the number of manufacturing steps and manufacturing costs can be suppressed, and productivity can be improved.

As described above, the current sensor 1 of this embodiment can improve assemblability while ensuring airtightness.

Here, the current sensor 1 described above is located across the pair of columnar parts 12a in the anchor part 12, and the hook-shaped part 12b formed to extend in the shape of a beam serves as a hook part for the potting material 9. Become. With this configuration, the current sensor 1 can be anchored by hooking the hook-shaped portion 12b onto the potting material 9 filled in the installation opening 64a. 9 can be properly maintained. As a result, the current sensor 1 can improve assemblability while ensuring airtightness as described above.

Further, in the current sensor 1 described above, when the battery terminal portion 2 is fastened to the battery post P, the cover member 10 is located on the opposite side of the post installation surface Bb, and the cover member 10 is located on the opposite side of the post installation surface Bb. The positional relationship is such that it closes the installation opening 64a that opens toward the side. In this way, the current sensor 1 is able to protect the outside of the potting material 9 by using the cover member 10 as described above in an environment where a fastening jig or the like tends to interfere with the potting material 9 etc. during the fastening work of the battery terminal portion 2, for example. It is possible to prevent foreign matter from interfering with the potting material 9. As a result, the current sensor 1 can prevent the quality from deteriorating due to the influence of the fastening work, etc., and perform proper quality control. In other words, the current sensor 1 can perform the fastening work easily, and Assemblability can be improved while ensuring airtightness. In this respect as well, the current sensor 1 can reduce manufacturing costs, for example.

Note that the current sensor according to the embodiment of the present invention described above is not limited to the embodiment described above, and various changes can be made within the scope of the claims.

The current sensor 1 according to the modified example shown in FIGS. 10 and 11 differs from the embodiment described above in that it includes a cover member 210 instead of the cover member 10. The cover member 210 differs from the embodiment described above in that it has an anchor portion 212 instead of the anchor portion 12. The other configurations of the current sensor 1 and the cover member 210 according to the modification are substantially the same as those of the above-described embodiment.

More specifically, the anchor portion 212 of this modification includes a columnar portion 212a and a hook-shaped portion 212b. The columnar part 212a is similar to the above-described columnar part 12a in that it extends along the protruding direction of the anchor part 212, here the axial direction X, but has a slightly different shape from the above-described columnar part 12a. One columnar portion 212a is provided for each anchor portion 212, and is formed into a substantially rectangular plate shape. The hook-shaped portion 212b of this modification has a claw shape that protrudes from the columnar portion 212a in a direction intersecting the axial direction X (projection direction), here, along the first width direction Y or the second width direction Z. is formed. That is, here, the hook-shaped portion 212b constitutes a claw-shaped portion that is formed to protrude from the protruding tip of the columnar portion 212a. A portion of the hook-shaped portion 12b that extends from the columnar portion 12a in a bent manner along a direction intersecting the axial direction X becomes a hook portion for the potting material 9.

Similarly to the cover member 10, in the cover member 210, a plurality of anchor portions 212 configured as described above are provided evenly along the wall portion forming the installation opening 64a, in this case, five anchor portions 212 are provided here. As described above, each anchor portion 212 is configured to include one columnar portion 212a and one hook-shaped portion 212b. Note that although the hook-shaped portion 212b is illustrated here as being formed in a shape that protrudes from the columnar portion 212a toward the outside of the installation opening 64a, the hook-shaped portion 212b is not limited to this. Furthermore, although the hook-shaped portion 212b has a shape that tapers toward the protruding tip, the shape is not limited to this, and the tip of the columnar portion 212a may simply be bent along the direction intersecting the axial direction X (protruding direction). , the shape may not be tapered.

In this case, in the current sensor 1 of this modification, in the anchor portion 212, the hook-shaped portion 212b protruding from the columnar portion 212a in a claw shape along the direction intersecting the axial direction X becomes a hook portion for the potting material 9. With this configuration, the current sensor 1 can be anchored by hooking the hook-shaped portion 212b on the potting material 9 filled in the installation opening 64a. 9 can be properly maintained. As a result, the current sensor 1 can improve assemblability while ensuring airtightness as described above.

In addition, in the above description, the current sensor 1 was described as being mounted on the vehicle V and configuring a battery terminal integrated sensor, but the current sensor 1 is not limited to this. The current sensor 1 may be applied to something other than the vehicle V, may be applied to a system other than the power supply system S, and does not need to be a battery terminal integrated sensor. Further, the current sensor 1 may be applied to either a low voltage system where the voltage is relatively low or a high voltage system where the voltage is relatively high in the vehicle V.

In the above description, the installation opening 64a opens toward the side opposite to the post installation surface Bb along the axial direction Although the explanation has been made assuming that the opening of the installation opening 64a is closed, the present invention is not limited to this. The installation opening 64a opens toward the post installation surface Bb side along the axial direction X, and the cover members 10, 210 are positioned on the post installation surface Bb side and close the installation opening 64a. There may be. Further, the installation opening 64a may be opened along the first width direction Y or the second width direction Z, and the cover member 10, 210 may close the installation opening 64a.

The cover members 10 and 210 described above may be provided with the anchor portion 12 and the anchor portion 212 mixed together.

In the above description, the hook-shaped portions 12b and 212b were explained as being formed at the protruding tips of the columnar portions 12a and 212a. It may be formed in the middle part of 12a, 212a, etc.

In the above description, the cover members 10, 210 were described as having a plurality of anchor parts 12, 212 evenly provided along the wall forming the installation opening 64a, but the cover members 10, 210 are not limited to this. One may be sufficient as long as it can be properly fixed.

In the above description, the cover members 10 and 210 were described as being made of resin or the like that has insulation and high heat resistance, but the cover members 10 and 210 are not limited thereto, and may be made of metal. In this case, the cover members 10 and 210 can also function as a noise countermeasure functional component and an EMC countermeasure functional component.

In the above description, the current sensor 1 has been described as configuring a so-called shunt type current sensor, but the present invention is not limited to this. For example, the sensor section includes a Hall IC configured with a Hall element that detects a magnetic field using the Hall effect, and the current sensor includes a magnetic field sensor that measures current by detecting changes in magnetic flux density using the Hall IC. A detection type current sensor may also be used.

The current sensor according to the present embodiment may be configured by appropriately combining the constituent elements of the embodiment and modified examples described above.

1 Current sensor 2 Battery terminal section 3 Terminal connection section 4 Sensor section 5 Stud bolt 6 Housing 7 Output terminal 8 Circuit board 9 Potting material 10, 210 Cover member 11 Main body section 11a Stepped section 12, 212 Anchor section 12a, 212a Column shape Parts 12b, 212b Hook-shaped part 64 Board cover part 64a Installation opening B Battery Bb Post installation surface C Central axis P Battery post V Vehicle X Axial direction (projection direction)
Y 1st width direction (direction intersecting the protruding direction)
Z Second width direction (direction intersecting the protruding direction)

Claims (4)

A sensor section that detects current;
a circuit board electrically connected to the sensor section;
a housing that accommodates the circuit board within an installation opening;
a potting material filled in the installation opening;
and a cover member that closes the installation opening,
The cover member has an anchor portion that is formed to protrude toward the potting material and includes a hook-shaped portion that is embedded within the potting material.
current sensor. The anchor portion includes a pair of columnar portions extending along the protruding direction of the anchor portion, and the hook-shaped portion,
The hook-shaped portion is formed in a beam shape that connects the pair of columnar portions along a direction intersecting the protruding direction.
The current sensor according to claim 1. The anchor part includes a columnar part extending along the protruding direction of the anchor part, and the hook-shaped part,
The hook-shaped portion is formed in a claw shape that protrudes from the columnar portion in a direction intersecting the protrusion direction.
The current sensor according to claim 1. comprising a battery terminal part that is electrically connected to the sensor part and fastened to a battery post provided on a battery post installation surface;
The cover member has the installation opening that is located on the opposite side of the post installation surface and opens toward the opposite side of the post installation surface when the battery terminal part is fastened to the battery post. block,
The current sensor according to any one of claims 1 to 3.

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