KR20230158416A - Current detection device - Google Patents

Abstract

[Problem] To provide a current detection device that can improve the stability of the connection with the shunt resistance in the substrate.
[Solution] The current detection device 1 includes a substrate 3 having a current detection portion, a first connection portion 51 connected to the substrate, and an intermediate portion 53 protruding from the first connection portion to be perpendicular to the substrate. and a connection terminal 5 having a second connection portion 52 connected to the shunt resistor 4 and a bent portion 54 connecting the second connection portion and the middle portion, and a connection terminal 5 that is integrally molded with the middle portion to hold the middle portion. and a fixed terminal 7 having a resin holding member 6 supported by a substrate, a base held by the holding member, a protruding portion 72, and the protruding portion being soldered to the substrate, and a second connection portion. It has a case 2 having an opening 22 exposing the shunt resistor, which is disposed on the outside of the case so as to face the opening and is fastened to the second connection portion by a screw member.

Description

Current detection device {CURRENT DETECTION DEVICE}

The present invention relates to a current detection device.

Conventionally, there is a technology for detecting current using a shunt resistor. Patent Document 1 discloses a current detection circuit that is electrically connected to a shunt resistor provided with a plurality of connection pins and detects a battery current flowing through the shunt resistor, a board on which the current detection circuit is mounted, and a connector mounted on the board. A battery control device provided is disclosed.

Japanese Patent Laid-open Publication No. 2020-201059

In a configuration that electrically connects a shunt resistor to a substrate, it is desirable to improve the stability of the connection portion in the substrate.

The object of the present invention is to provide a current detection device that can improve the stability of the connection portion with the shunt resistance in the substrate.

The current detection device of the present invention includes a substrate having a current detection portion, a first connection portion electrically connected to the substrate, an intermediate portion protruding from the first connection portion to be perpendicular to the substrate, and electrically connected to a shunt resistor. A connection terminal having a second connection portion, a bending portion connecting the second connection portion and the intermediate portion, and a resin material that is integrally molded with the intermediate portion to hold the intermediate portion and is supported by the substrate. a fixing terminal having a holding member, a base held by the holding member, and a protruding portion protruding from the holding member, the protruding portion being soldered to the substrate, thereby fixing the holding member to the substrate; a case accommodating the substrate, the connection terminal, the fixing terminal, and the retaining member, and having an opening exposing the second connection portion, the case being disposed outside the case so as to face the opening, and the second Characterized in that the shunt resistor is fastened to the connection portion by a screw member.

In the current detection device according to the present invention, the mechanical strength is improved because the holding member is integrally molded with the middle portion of the connection terminal. Additionally, because the connection terminal has a bent portion between the intermediate portion and the second connection portion, it is difficult for the external force acting on the second connection portion to be transmitted to the first connection portion. Additionally, the holding member is firmly fixed to the substrate by the fixing terminal. The current detection device according to the present invention has the effect of improving the stability of the connection portion with the shunt resistance in the substrate.

1 is a perspective view of a current detection device according to an embodiment.
Fig. 2 is an exploded perspective view of the current detection device according to the embodiment.
Fig. 3 is a perspective view of a holding member and a terminal according to the embodiment.
Fig. 4 is a perspective view of a connection terminal according to the embodiment.
Fig. 5 is a perspective view of a fixed terminal according to the embodiment.
FIG. 6 is a diagram illustrating the assembly process of the current detection device according to the embodiment.
Fig. 7 is a cross-sectional view of a current detection device according to the embodiment.

Below, a current detection device according to an embodiment of the present invention will be described in detail with reference to the drawings. Additionally, the present invention is not limited to this embodiment. In addition, the components in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

[Embodiment]

With reference to FIGS. 1 to 7, embodiments will be described. This embodiment relates to a current detection device. FIG. 1 is a perspective view of a current detection device according to the embodiment, FIG. 2 is an exploded perspective view of a current detection device according to the embodiment, FIG. 3 is a perspective view of a holding member and a terminal according to the embodiment, and FIG. 4 is a perspective view of a current detection device according to the embodiment. FIG. 5 is a perspective view of a connection terminal related to the embodiment, FIG. 6 is a diagram illustrating an assembly process of the current detection device according to the embodiment, and FIG. 7 is a current detection device according to the embodiment. This is a cross-sectional view of .

1 to 3, the current detection device 1 of the present embodiment includes a case 2, a substrate 3, a shunt resistor 4, a connection terminal 5, a holding member 6, It has a fixed terminal (7) and a screw member (8). The current detection device 1 is, for example, disposed in a vehicle battery and detects the charge/discharge current of the battery. The current detection device 1 is a so-called shunt type current sensor. That is, the current detection device 1 causes a current to flow through the shunt resistor 4 and measures the current value using Ohm's law from the voltage drop when the current is applied and the resistance value of the shunt resistor 4.

The shape of the illustrated shunt resistor 4 is a rectangular plate shape. Bus bars are connected to both ends of the shunt resistor 4, respectively. One bus bar is connected to the negative electrode of the battery, for example. The other bus bar is connected to a ground portion of, for example, a vehicle body. Based on the current value detected by the current detection device 1, monitoring and control of the battery are performed.

As shown in FIG. 2 and the like, the current detection device 1 of the present embodiment has a pair of connection terminals 5 that connect the shunt resistor 4 and the substrate 3. The current detection unit 31 included in the substrate 3 is connected to the shunt resistor 4 via a connection terminal 5. The current detection unit 31 is, for example, a current detection circuit. The current detection device 1 of this embodiment has a holding member 6 that holds the connection terminal 5. As explained below, the holding member 6 can improve current detection accuracy and improve the stability of the connection point between the connection terminal 5 and the substrate 3.

Case 2 accommodates board 3, connection terminal 5, holding member 6, and fixed terminal 7. Case 2 is molded, for example, from insulating synthetic resin. The illustrated case 2 has a rectangular cylinder shape. One end of the case 2 has an insertion port 21. The board 3, the connection terminal 5, the holding member 6, and the fixed terminal 7 are inserted into the case 2 through the insertion port 21. Inside the case 2, a guide portion 23 for guiding the substrate 3 and a locking portion for locking the substrate 3 are provided.

In the following description, the direction of insertion of the substrate 3 into the case 2 is referred to as the “first direction (X).” The first direction (X) is the axial direction of the cylindrical case 2. Additionally, the width direction of the case 2 and the substrate 3 is referred to as the “second direction (Y),” and the height direction of the case 2 is referred to as the “third direction (Z).” The third direction Z is the thickness direction of the substrate 3. The first direction (X), the second direction (Y), and the third direction (Z) are orthogonal to each other.

Inside the case 2 in the first direction The concave portion 24 is formed on the outer surface of the case 2. The shape of the concave portion 24 in plan view is a rectangle according to the shape of the shunt resistor 4. Two openings 22 are provided in the concave portion 24. The two openings 22 are aligned along the second direction Y. The shape of the opening 22 is, for example, rectangular. The board 3 is inserted into the case 2 to a position where the second connection portion 52 of the connection terminal 5 faces the opening 22 . The case 2 holds the substrate 3 with the second connection portion 52 exposed through the opening 22 .

Case 2 holds two nuts 10. The nut 10 is press-fitted into the case 2 along the first direction (X). The shunt resistor 4 has a pair of first through holes 41, a pair of second through holes 42, and a pair of third through holes 43. The through holes 41, 42, and 43 are aligned along the second direction (Y). The first through hole 41 is located on the innermost side, and the third through hole 43 is located on the outermost side.

The first through hole 41 is a through hole corresponding to the screw member 8. The screw member 8 is inserted into the first through hole 41 and screwed into the second connection portion 52 of the connection terminal 5. The second through hole 42 is a through hole corresponding to the screw member 11. The screw member 11 is a fastening member that secures the shunt resistor 4 to the case 2. The screw member 11 is inserted through the second through hole 42 and screwed to the screw hole of the case 2. The case 2 may hold a nut corresponding to the screw member 11.

The third through hole 43 is a through hole corresponding to the nut 10. Each of the above bus bars is fixed to the shunt resistor 4 by a screw member and nut 10, not shown. Each bus bar may have a through hole corresponding to the third through hole 43. In this case, the screw member is inserted into the through hole of the bus bar and the third through hole 43 and screwed together with the nut 10.

A connector 32 is disposed on the board 3. The current detection unit 31 may be connected to an external monitoring device via the connector 32. The cover 9 engages the case 2 and closes the insertion opening 21 of the case 2. The cover 9 has a through hole corresponding to the connector 32.

As shown in Fig. 3, the holding member 6 holds two connecting terminals 5 and one fixed terminal 7. The illustrated holding member 6 is molded from an insulating synthetic resin. The holding member 6 is integrated with the two connecting terminals 5 and the fixed terminal 7 by insert molding. The fixed terminal 7 is insulated from the connecting terminal 5. The shape of the holding member 6 is approximately a rectangular parallelepiped shape.

Regarding the connection terminal 5, the holding member 6, and the fixed terminal 7, the holding member 6 is fixed to the substrate 3 and accommodated in the case 2 in each direction (X , Y, Z) are used to explain. The two connection terminals 5 have a first connection terminal 5A and a second connection terminal 5B. The two connection terminals 5 are arranged at the first end 6a of the holding member 6. The fixed terminal 7 is disposed at the second end 6b of the holding member 6. The first end 6a and the second end 6b are ends of the holding member 6 in the first direction (X). That is, the fixed terminal 7 is arranged at a position away from the two connection terminals 5 in the first direction (X). The fixed terminal 7 is disposed between the two female screw portions 56 in the second direction (Y). That is, the fixed terminal 7 is disposed between the two female screw portions 56 when the substrate 3 is viewed in plan view.

The two connection terminals 5 are arranged along the second direction (Y). The first connection terminal 5A is placed at one end in the second direction (Y), and the second connection terminal 5B is placed at the other end in the second direction (Y). The fixed terminal 7 is disposed at the center in the second direction (Y). That is, the position of the fixed terminal 7 in the second direction Y is a position between the first connection terminal 5A and the second connection terminal 5B, for example, a central position.

As shown in FIG. 4 , the connection terminal 5 has a first connection portion 51, a second connection portion 52, an intermediate portion 53, and a bent portion 54. The connection terminal 5 is formed of a conductive metal such as copper. The connection terminal 5 is formed, for example, from a single metal plate. The first connection portion 51 is physically and electrically connected to the substrate 3. The shape of the illustrated first connection portion 51 is a flat plate or a prism shape. The first connection portion 51 is inserted into a through hole of the board 3 and soldered to the board 3. The first connection portion 51 is connected to the current detection portion 31 via the circuit pattern of the substrate 3.

The second connection portion 52 is fastened to the shunt resistor 4 by a screw member 8. The illustrated second connection portion 52 has a flat body 55 and a cylindrical female thread portion 56. The shape of the main body 55 in plan view is rectangular. The female thread portion 56 protrudes from the central portion of the main body 55 toward the first connection portion 51. On the inner peripheral surface of the female thread portion 56, a female thread is formed by tapping. At the entrance of the female screw portion 56, an attractive inclined surface 56a is provided.

The intermediate portion 53 is encapsulated in the resin of the holding member 6 and held by the holding member 6. The middle part 53 is a part between the first connection part 51 and the second connection part 52. The middle part 53 is continuous with the first connection part 51 and is located on an extension line of the first connection part 51. The shape of the illustrated middle portion 53 is a flat plate shape. The middle portion 53 has a tapered shape whose width gradually narrows as it moves toward the first connection portion 51 along the third direction Z. The side surface of the middle portion 53 has a plurality of inclined surfaces 53a. The inclined surface 53a is inclined so as to approach the center line of the middle portion 53 as it approaches the first connection portion 51 along the third direction Z. A step portion 53b is provided at the end of the middle portion 53. The step portion 53b is disposed at an end portion on the side of the middle portion 53 on the second connection portion 52 side.

The bent portion 54 connects the middle portion 53 and the second connection portion 52. The illustrated bent portion 54 is bent so as to make the second connecting portion 52 orthogonal to the first connecting portion 51 . The first connection portion 51 and the intermediate portion 53 extend along the third direction (Z), and the second connection portion 52 extends along the first direction (X). The shape of the bent portion 54 when viewed from the side is an arc-shaped curved shape. The width Wd2 of the bent portion 54 is narrower than the width Wd1 of the middle portion 53 and is narrower than the width Wd3 of the second connection portion 52. That is, the bent portion 54 has a lower rigidity compared to the intermediate portion 53 and the second connecting portion 52, and is prone to elastic deformation.

As shown in Fig. 5, the fixed terminal 7 has a base 71 and a protrusion 72. The fixed terminal 7 is formed of a metal plate. The fixed terminal 7 may have conductivity. The base 71 is encapsulated in the resin of the holding member 6 and held by the holding member 6. The protruding portion 72 is a portion that protrudes from the holding member 6 along the third direction Z.

The base 71 has a flat plate shape and extends along the third direction Z. The base 71 has a tapered shape whose width gradually narrows as it moves toward the protrusion 72 along the third direction Z. The side surface of the base 71 has a plurality of inclined surfaces 71a. The inclined surface 71a is inclined so as to approach the center line of the base 71 as it approaches the protrusion 72 along the third direction Z. A step portion 71b is provided at the end of the base 71. The step portion 71b is disposed at an end of the base 71 on the opposite side to the protruding portion 72 side.

The shape of the illustrated protrusion 72 is a flat plate or a prism shape. The protrusion 72 is inserted into a through hole of the board 3 and soldered to the board 3. The fixed terminal 7 fixes the holding member 6 to the substrate 3 by soldering the protruding portion 72 to the substrate 3 .

As shown in Fig. 3, the first connecting portion 51 of the connecting terminal 5 and the protruding portion 72 of the fixed terminal 7 protrude from the holding member 6 along the third direction Z. . The first connection portion 51 and the protruding portion 72 protrude toward the first side Z1. The first side Z1 is the side of the substrate 3 when viewed from the holding member 6. That is, the first connection portion 51 and the protruding portion 72 protrude from the holding member 6 toward the substrate 3 side.

The second connection portion 52 and the bent portion 54 of the connection terminal 5 protrude from the holding member 6 along the third direction Z. The second connection portion 52 and the bent portion 54 protrude toward the second side Z2. The second side Z2 is the shunt resistance 4 side when viewed from the holding member 6. That is, the second connection portion 52 and the bent portion 54 protrude from the holding member 6 toward the shunt resistor 4 side. The main body 55 and the female thread portion 56 of the second connection portion 52 face the holding member 6 in the third direction Z. The female thread portion 56 protrudes from the main body 55 toward the holding member 6 along the third direction Z.

The holding member 6 has three leg portions 61, 62, and 63 protruding toward the first side Z1. The three leg portions 61, 62, and 63 are supported by the substrate 3. The first leg portion 61 is disposed on the first end 6a side, and the second leg portion 62 and the third leg portion 63 are disposed on the second end 6b side.

The first leg portion 61 is located between the two first connection portions 51 . The first leg portion 61 protrudes from the first end 6a toward the first side Z1. The shape of the first leg portion 61 when viewed from the first direction (X) is rectangular. The front end surface of the first leg portion 61 is mounted on and supported by the substrate 3 .

The second leg portion 62 and the third leg portion 63 are arranged at the corners of the holding member 6. The second leg portion 62 and the third leg portion 63 are disposed with the protruding portion 72 of the fixed terminal 7 sandwiched between them. In other words, the second leg portion 62 is disposed on one side in the second direction (Y) with respect to the protruding portion 72, and the third leg portion 63 is disposed in the second direction (Y) with respect to the protruding portion 72. It is placed on the other side of Y). The shape of the second leg portion 62 and the third leg portion 63 when the holding member 6 is viewed from the first side Z1 is approximately L-shaped and is bent at a right angle. The second leg portion 62 and the third leg portion 63 have a portion extending in the first direction (X) and a portion extending in the second direction (Y), respectively. The tip surfaces of the second leg portion 62 and the third leg portion 63 are mounted on and supported by the substrate 3 .

The holding member 6 has projections 64 and 65 protruding toward the first side Z1. The projection 64 protrudes from the second leg portion 62, and the projection 65 protrudes from the third leg portion 63. The shape of the illustrated projections 64 and 65 is cylindrical. The substrate 3 has positioning portions corresponding to the projections 64 and 65. The positioning portion is a recess or hole formed in the substrate 3. By inserting the projections 64 and 65 into the positioning portion, the holding member 6 is positioned with respect to the substrate 3.

As shown in FIG. 2 , the holding member 6 is mounted on the first surface 3a of the substrate 3 . The board 3 has through holes corresponding to the connecting terminals 5 and the fixed terminals 7 . The first connecting portion 51 of the connecting terminal 5 and the protruding portion 72 of the fixed terminal 7 are inserted into the corresponding through holes. The first connecting portion 51 and the protruding portion 72 are fixed to the second surface 3b of the substrate 3 by soldering. The first connection portion 51 is connected to the circuit pattern of the substrate 3. The protruding portion 72 is connected to a land for fixing, etc.

Fig. 6 shows a case 2 housing connection terminals 5 and the like at specified positions. The second connection portion 52 of the connection terminal 5 is exposed to the opening 22 of the case 2. The shunt resistor 4 is mounted in the concave portion 24 of the case 2 so as to face the opening 22, and is fixed to the case 2 by a screw member 11. The second connection portion 52 of each connection terminal 5 is fastened to the shunt resistor 4 by a screw member 8. The screw member 8 is inserted into the first through hole 41 of the shunt resistor 4 and screwed to the female thread portion 56 of the connection terminal 5.

7 shows an X-Z cross section including the screw member 8 and the connection terminal 5. The cross section in FIG. 7 is a cross section along the central axis of the screw member 8. As shown in Fig. 7, the first through hole 41 of the shunt resistor 4 faces the female thread portion 56 in the third direction Z. The screw member 8 is screwed with the female screw portion 56, and brings the main body 55 of the connection terminal 5 into contact with the shunt resistor 4. The screw member 8 has conductivity and can electrically connect the shunt resistor 4 and the second connection portion 52.

The first connection portion 51 of the connection terminal 5 is connected to the substrate 3 by a solder 12 and is fixed to the substrate 3. The middle portion 53 protrudes from the first connection portion 51 toward the shunt resistor 4 so as to be perpendicular to the substrate 3 . The protrusion 72 of the fixed terminal 7 is fixed to the substrate 3 with a solder 12. The holding member 6 is mounted on the substrate 3 and is fixed to the substrate 3 with solder 12.

Here, when the screw member 8 is screwed to the female screw portion 56, an external force acts on the second connection portion 52. The connection terminal 5 and the holding member 6 of this embodiment can suppress this external force from being transmitted to the first connection portion 51. When an external force acts on the second connection part 52, the bent portion 54 of the connection terminal 5 is elastically deformed and can absorb the external force. Additionally, when the screw member 8 is inserted into the female screw member 56 in an inclined position, the bent portion 54 is elastically deformed, allowing the female screw member 56 to follow the screw member 8.

Additionally, the holding member 6 is integrally molded with the middle portion 53 of the connection terminal 5 and holds the middle portion 53. Accordingly, the holding member 6 can suppress transmission of the external force acting on the second connecting portion 52 to the first connecting portion 51. For example, the holding member 6 is supported by the substrate 3 and can support the middle portion 53 by resisting a force in the third direction Z.

Additionally, the holding member 6 is fixed to the substrate 3 via the fixing terminal 7. Accordingly, the force received by the holding member 6 is distributed to the connection portion between the fixed terminal 7 and the substrate 3. The fixed terminals 7 are arranged apart from the middle portion 53 of the connecting terminal 5 in the first direction (X). Therefore, the fixed terminal 7 can stabilize the holding member 6 against force or moment in the first direction (X).

The current detection device 1 of this embodiment can reduce the influence of external force on the connection point between the connection terminal 5 and the substrate 3 and improve the stability of the connection point. Therefore, the current detection device 1 of this embodiment can transmit an electric signal from the shunt resistor 4 to the substrate 3 without losing accuracy, thereby ensuring current measurement accuracy. In addition, the current detection device 1 of this embodiment can reduce the exclusive area of the device by integrating the shunt resistor 4 on the upper surface of the case 2.

As explained above, the current detection device 1 of the present embodiment includes a substrate 3 having a current detection portion 31, a connection terminal 5, a resin retaining member 6, and a fixed terminal. It has (7), case (2), and shunt resistance (4). The connection terminal 5 has a first connection portion 51, an intermediate portion 53, a second connection portion 52, and a bent portion 54. The first connection portion 51 is electrically connected to the substrate 3. The middle portion 53 protrudes from the first connection portion 51 so as to be perpendicular to the substrate 3 . The second connection portion 52 is electrically connected to the shunt resistor 4. The bent portion 54 connects the second connecting portion 52 and the intermediate portion 53.

The holding member 6 is integrally molded with the middle portion 53, holds the middle portion 53, and is also supported by the substrate 3. The fixed terminal 7 has a base 71 held by a holding member 6 and a protruding portion 72 protruding from the holding member 6. The fixed terminal 7 fixes the holding member 6 to the substrate 3 by soldering the protruding portion 72 to the substrate 3 . Case 2 accommodates substrate 3, connection terminal 5, fixed terminal 7, and holding member 6. Case 2 has an opening 22 exposing the second connection portion 52 . The shunt resistor 4 is disposed outside the case 2 so as to face the opening 22. The shunt resistor 4 is fastened to the second connection portion 52 by a screw member 8.

In the current detection device 1 of this embodiment, the holding member 6 is integrally molded with the middle portion 53 of the connection terminal 5, thereby improving mechanical strength. In addition, since the connection terminal 5 has a bent portion 54 between the middle portion 53 and the second connection portion 52, the external force acting on the second connection portion 52 is transmitted to the first connection portion 51. It's hard to lose. Additionally, the holding member 6 is firmly fixed to the substrate 3 by the fixing terminals 7. Therefore, the current detection device 1 of this embodiment can improve the stability of the connection portion with the shunt resistor 4 in the substrate 3. For example, the stability of the soldering point between the first connection portion 51 and the board 3 is improved.

The second connection portion 52 of this embodiment includes a flat body 55 in contact with the shunt resistor 4, and a cylindrical female thread portion 56 protruding from the body 55 toward the substrate 3. ) has. The shunt resistor 4 has a first through hole 41, and the first through hole 41 faces the female thread portion 56. The screw member 8 is inserted into the first through hole 41 and screwed to the female screw portion 56 to fasten the second connection portion 52 and the shunt resistor 4. In this configuration, the external force when the screw member 8 is screwed to the female screw portion 56 is absorbed by the bent portion 54.

The holding member 6 of this embodiment holds the middle portion 53 of the two connection terminals 5. The two female threaded portions 56 face the retaining member 6. The fixed terminal 7 is disposed between two female screw portions 56 when the substrate 3 is viewed in plan view. Accordingly, the fixed terminal 7 can appropriately support the retaining member 6 against external force when the screw member 8 is screwed to each female screw portion 56.

Additionally, the shape of the bent portion 54 is not limited to the illustrated shape. For example, the bent portion of the bent portion 54 is not limited to one. The bent portion 54 may be bent in two or more places.

The shape of the holding member 6 is not limited to the illustrated shape. The holding member 6 may hold a plurality of fixed terminals 7. In this case, the plurality of fixed terminals 7 are each soldered to the board 3.

The contents disclosed in the above embodiments can be implemented by combining them appropriately.

1: Current detection device
2: Case
3: substrate
3a: side 1
3b: side 2
4: Shunt resistance
5: Connection terminal
5A: 1st connection terminal
5B: 2nd connection terminal
6: Absence of pussy
6a: first end
6b: second end
7: fixed terminal
8: Screw member
9: cover
10: nut
11: screw member
21: Insertion hole
22: opening
41: first through hole
42: second through hole
43: third through hole
51: first connection part
52: second connection part
53: middle part
53a: slope
54: bend part
55: main body
56: female thread part
61: first leg portion
62: second leg portion
63: Third leg portion
71: Donate
71a: slope
72: protrusion
X: first direction
Y: second direction
Z: third direction

Claims (3)

A substrate having a current detection unit,
A first connection portion electrically connected to the substrate, a middle portion protruding from the first connection portion to be perpendicular to the substrate, a second connection portion electrically connected to a shunt resistor, and connecting the second connection portion and the middle portion. A connection terminal having a bent portion,
a resin retaining member that is integrally molded with the intermediate portion, holds the intermediate portion, and is supported by the substrate;
a fixing terminal having a base held by the holding member and a protrusion protruding from the holding member, the protrusion being soldered to the substrate, thereby fixing the holding member to the substrate;
a case accommodating the substrate, the connection terminal, the fixing terminal, and the holding member, and having an opening exposing the second connection portion;
The shunt resistor is disposed outside the case so as to face the opening and is fastened to the second connection portion by a screw member.
A current detection device comprising: According to claim 1,
The second connection portion has a flat body in contact with the shunt resistor and a cylindrical female thread portion protruding from the body toward the substrate,
The shunt resistor has a through hole, and the through hole is opposed to the female thread portion,
The current detection device wherein the screw member is inserted into the through hole and screwed to the female screw portion to fasten the second connection portion and the shunt resistor. According to claim 2,
The holding member holds the middle portion of the two connecting terminals,
The two female threads face the retaining member,
A current detection device wherein the fixed terminal is disposed between the two female screw portions when the substrate is viewed in a planar view.