Current detection device

Abstract

To provide a current detector that can easily detect a current and suppress deterioration in current detection accuracy.SOLUTION: In a current detector, a first bus bar portion 21 includes a first side surface 211, a first recess 212, and a first rectification portion 213. The first side surface 211 crosses a width direction DW. The first recess 212 is recessed from the first side surface 211 to the width direction DW. The first rectification portion 213 extends in the width direction DW while adjacent to the first recess 212, and through which a current from battery 12 flows. The first rectification portion 213 further includes a first end 2131 and a second end 2132. A surface that passes through the first end 2131 and is orthogonal to the width direction DW is used as a first surface S1. Also, a surface that passes through the second end 2132 and is orthogonal to the width direction DW is used as a second surface S2. A first voltage detection point P1 and a second voltage detection point P2 are arranged in a range from the first surface S1 to the second surface S2 in the width direction DW.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a current detection device.

Background Art

[0002] Conventionally, as described in Patent Document 1, a measuring resistor having a plurality of pairs of voltage measurement contacts for measuring a voltage drop across both ends of a resistance element is known. In this measuring resistor, a plurality of voltage values are simultaneously measured by the plurality of pairs of voltage measurement contacts, and a voltage value is derived from these measured values by weighted averaging, whereby non-uniformity in current density is quantitatively compensated.

Prior Art Literature

Patent Literature

[0003]

Patent Literature 1

Summary of Invention

Problem to be Solved by the Invention

[0004] In the measuring resistor described in Patent Document 1, current detection accuracy is improved because a plurality of voltage values are used to quantitatively compensate for non-uniformity in current density. However, according to studies by the inventor, since a plurality of voltage values are used, current calculation becomes complicated. This increases calculation load.

[0005] An object of the present disclosure is to provide a current detection device that can easily detect current and suppress a decrease in current detection accuracy.

Means for Solving the Problem

[0006] The invention described in claim 1 is a current detection device comprising: a first busbar portion (21) formed in the shape of a plate; a resistor portion (31) connected to the first busbar portion and having an electrical resistance greater than that of the first busbar portion; a second busbar portion (22) connected to the resistor portion on the side opposite to the first busbar portion and having an electrical resistance less than that of the resistor portion; and a first terminal portion (6) that outputs a signal corresponding to a first voltage (V1), which is the voltage applied to the side of the resistor portion that faces the first busbar portion. 1) a second terminal section (62) that outputs a signal corresponding to a second voltage (V2) which is the voltage applied to the second busbar section of the resistor section, a substrate (40, 41) on which the first terminal section and the second terminal section are arranged, a first connection section (51) connected to the substrate, the resistor section side of the first busbar section, and the first terminal section, a second connection section (52) connected to the substrate, the resistor section side of the second busbar section, and the second terminal section, and a first detection point (P) which is the contact point between the first terminal section and the first connection section 1) comprises a second detection point (P2) which is the contact point between the second terminal and the second connection, and a calculation unit (120) which calculates a device current (Ib) which is the current flowing from an external device (12) to the second busbar via the first busbar and the resistor, based on the first voltage, the second voltage, and the electrical resistance of the resistor, wherein the first busbar has a side surface (211) that intersects with the width direction (DW) of the first busbar, a recess (212) that is recessed in the width direction from the side surface, and a part that extends in the width direction adjacent to the recess in the width direction The current detection device includes a rectifier section (213) through which current from an external device flows, and the rectifier section includes a first end (2131) which is the boundary with the recess and a second end (2132) which is the end opposite to the first end, and if the surface passing through the first end and perpendicular to the width direction is designated as the first surface (S1) and the surface passing through the second end and perpendicular to the width direction is designated as the second surface (S2), then the first detection point and the second detection point are arranged in the width direction within the range from the first surface to the second surface.

[0007] Furthermore, the invention described in claim 11 is a current detection device comprising: a first busbar portion (21) formed in the shape of a plate; a resistor portion (31) connected to the first busbar portion and having an electrical resistance greater than that of the first busbar portion; a second busbar portion (22) connected to the resistor portion on the side opposite to the first busbar portion and having an electrical resistance less than that of the resistor portion; and a first terminal portion (61) that outputs a signal corresponding to a first voltage (V1), which is the voltage applied to the side of the resistor portion that is the first busbar portion. The circuit includes a second terminal (62) that outputs a signal corresponding to a second voltage (V2), which is the voltage applied to the second busbar side of the resistor; a circuit board (40, 41) on which the first terminal and second terminal are arranged; a first connection (51) connected to the circuit board, the resistor side of the first busbar, and the first terminal; a second connection (52) connected to the circuit board, the resistor side of the second busbar, and the second terminal; a first detection point (P1) which is the contact point between the first terminal and the first connection; and the second terminal The first busbar comprises a second detection point (P2), which is the contact point between the busbar and the second connection point, and a calculation unit (120) that calculates the device current (Ib), which is the current flowing from the external device (12) to the second busbar via the first busbar and the resistor, based on the first voltage, the second voltage, and the electrical resistance of the resistor. The first busbar comprises a plate surface (215) intersecting the thickness direction (DT) of the first busbar, a hole (216) extending in the thickness direction from the inside of the plate surface, and a hole adjacent to the width direction (DW) of the first busbar. The current detection device has a rectifier section (213) that extends in (DW) and through which current from an external device flows, and the rectifier section includes a first end (2131) which is the boundary with the hole and a second end (2132) which is the end opposite to the first end, and if the surface passing through the first end and perpendicular to the width direction is called the first surface (S1) and the surface passing through the second end and perpendicular to the width direction is called the second surface (S2), then the first detection point and the second detection point are arranged in the width direction within the range from the first surface to the second surface.

[0008] Furthermore, the invention described in claim 12 is a current detection device comprising: a first busbar portion (21) formed in the shape of a plate; a resistor portion (31) connected to the first busbar portion and having an electrical resistance greater than that of the first busbar portion; a second busbar portion (22) connected to the resistor portion on the side opposite to the first busbar portion and having an electrical resistance less than that of the resistor portion; a first terminal portion (61) connected to the first busbar portion and outputting a signal corresponding to a first voltage (V1) which is the voltage applied to the side of the resistor portion on the first busbar portion side; a second terminal portion (62) connected to the second busbar portion and outputting a signal corresponding to a second voltage (V2) which is the voltage applied to the side of the resistor portion on the second busbar portion side; a first detection point (P1) which is the contact point between the first terminal portion and the first busbar portion; a second detection point (P2) which is the contact point between the second terminal portion and the second busbar portion; and the first voltage The device includes a calculation unit (120) that calculates a device current (Ib), which is a current flowing from an external device (12) to the second busbar section via the first busbar section and the resistor section, based on the second voltage and the electrical resistance of the resistor section. The first busbar section has a side surface (211) that intersects with the width direction (DW) of the first busbar section, a recess (212) that is recessed in the width direction from the side surface, and a rectifier section (213) that extends in the width direction adjacent to the recess in the width direction and through which current from the external device flows. The rectifier section includes a first end (2131) which is the boundary with the recess and a second end (2132) which is the end opposite to the first end. If the surface passing through the first end and perpendicular to the width direction is called the first surface (S1) and the surface passing through the second end and perpendicular to the width direction is called the second surface (S2), then the first detection point and the second detection point are current detection devices arranged in the width direction within the range from the first surface to the second surface.

[0009] The range of current flowing through the rectifier section is smaller than that of the non-rectifier section of the first busbar. As a result, the current flowing through the rectifier section is rectified. Therefore, the current density of the rectifier section increases. In addition, the first and second detection points are positioned in the width direction from the first surface to the second surface. As a result, signals corresponding to the voltage that corresponds to the increased current density due to the rectifier section are output from the first and second terminal sections. Therefore, the sensitivity to the device current is improved. Consequently, the signal-to-noise ratio for the device current is improved, and the decrease in current detection accuracy is suppressed. Furthermore, since it is no longer necessary to measure multiple pairs of voltages, the complexity of calculations is suppressed. Therefore, current detection can be performed simply, and the decrease in current detection accuracy is suppressed.

[0010] The reference numerals in parentheses attached to each component indicate an example of the correspondence between that component and the specific components described in the embodiments described later. [Brief explanation of the drawing]

[0011] [Figure 1] A diagram showing the configuration of the current detection device of the first embodiment and a motor generator system in which the current detection device is used. [Figure 2] A top view of a part of the current detection device. [Figure 3] Enlarged section of line III-III in Figure 1. [Figure 4] Enlarged view of the section along line IV-IV in Figure 1. [Figure 5] A flowchart illustrating the manufacturing method of a current detection device. [Figure 6] A diagram showing the preparation steps in the manufacturing method of a current detection device. [Figure 7] A diagram showing the connection process in the manufacturing method of a current detection device. [Figure 8] A diagram showing the molding process in the manufacturing method of a current detection device. [Figure 9] Enlarged view of section IX in Figure 8. [Figure 10]Configuration diagram of a current detection device according to a second embodiment and a motor generator system in which the current detection device is used. [Figure 11] Enlarged cross-sectional view taken along line XI‐XI in FIG. 10. [Figure 12] Enlarged cross-sectional view taken along line XII‐XII in FIG. 10. [Figure 13] Top view of a part of a current detection device according to a third embodiment. [Figure 14] Top view of a part of a current detection device according to a fourth embodiment. [Figure 15] Top view of a part of a current detection device according to a fifth embodiment. [Figure 16] Top view of a part of a current detection device according to a sixth embodiment. [Figure 17] Cross-sectional view of a part of a current detection device according to a seventh embodiment. [Figure 18] Cross-sectional view of a part of a current detection device. [Figure 19] Cross-sectional view of a part of a current detection device according to an eighth embodiment. [Figure 20] Cross-sectional view of a part of a current detection device. [Figure 21] Configuration diagram of a current detection device according to a ninth embodiment and a motor generator system in which the current detection device is used. MODE FOR CARRYING OUT THE INVENTION

[0012] Embodiments will be described below with reference to the drawings. In the following respective embodiments, the same or equivalent portions are denoted by the same reference symbols, and description thereof will be omitted.

[0013] (First Embodiment) The current detection device (20) of the present embodiment is used, for example, in a motor generator system (10) of a vehicle not shown in the drawings. First, this motor generator system (10) will be described.

[0014] As shown in FIG. 1, the motor generator system (10) includes a battery (12), an inverter (14), a motor generator (16), and the current detection device (20).

[0015] The battery 12 is, for example, a lithium-ion secondary battery or a nickel-metal hydride secondary battery. The inverter 14 is connected to the battery 12. The inverter 14 converts the direct current flowing from the battery 12 to the inverter 14 via the current detection device 20 (described later) into alternating current. Furthermore, the inverter 14 supplies this converted alternating current to the motor generator 16 (described later).

[0016] The motor generator 16 rotates using alternating current from the inverter 14. This causes, for example, the wheels of a vehicle (not shown) to rotate. The motor generator 16 also generates electricity based on the power input in reverse from the wheels of the vehicle (not shown). This generated current is converted from alternating current to direct current by the inverter 14. This converted direct current charges the battery 12.

[0017] The current detection device 20 is connected to the battery 12 and the inverter 14. The current detection device 20 also detects and calculates the current flowing from the battery 12 to the inverter 14.

[0018] Specifically, as shown in Figures 1 to 4, the current detection device 20 includes a first busbar section 21, a first resistor section 31, a second busbar section 22, an intermediate section 25, a third busbar section 23, a second resistor section 32, and a fourth busbar section 24. The current detection device 20 also includes a first substrate 41, a second substrate 42, a first connection section 51, a second connection section 52, a third connection section 53, a fourth connection section 54, a first terminal section 61, a second terminal section 62, a third terminal section 63, and a fourth terminal section 64. Furthermore, the current detection device 20 includes a first voltage detection point P1, a second voltage detection point P2, a third voltage detection point P3, a fourth voltage detection point P4, a first wiring 71, a second wiring 72, a third wiring 73, a fourth wiring 74, a first pin 81, a second pin 82, a third pin 83, and a fourth pin 84. The current detection device 20 also includes a first thermistor 91, a second thermistor 92, a third thermistor 93, and a fourth thermistor 94. Furthermore, the current detection device 20 includes two pins 101 for the first thermistor, two pins 102 for the second thermistor, two pins 103 for the third thermistor, and two pins 104 for the fourth thermistor. The current detection device 20 also includes a first connector housing 111, a second connector housing 112, and a calculation unit 120.

[0019] The first busbar portion 21 is formed in a plate shape from copper or the like. Hereafter, for convenience, the longitudinal direction DL of the first busbar portion 21 will be simply referred to as the longitudinal direction DL. Also, the width direction DW of the first busbar portion 21 will be simply referred to as the width direction DW. Furthermore, the thickness direction DT of the first busbar portion 21 will be simply referred to as the thickness direction DT.

[0020] Furthermore, as shown in Figures 1 and 2, the first busbar section 21 has a first connection hole 210, a first side surface 211, a first recess 212, and a first rectifier section 213.

[0021] Bolts (not shown) are inserted into the first connection hole 210 and a hole in the battery 12. This connects the first busbar section 21 to the battery 12.

[0022] The first side surface 211 is a surface of the first busbar portion 21 that is perpendicular to the width direction DW and corresponds to a surface of the first busbar portion 21 that intersects with the width direction DW.

[0023] The first recess 212 is recessed in the width direction DW from both first side surfaces 211. Furthermore, the first recess 212 penetrates in the thickness direction DT. In addition, the first recess 212 is not in contact with the first resistive portion 31, which will be described later, and is separated from it. Note that, while there are two first recesses 212 here, the number is not limited to this. At least one first recess 212 is sufficient. Also, while the shape of the first recess 212 is a rectangular prism, the shape is not limited to this. The shape of the first recess 212 may be a polygonal prism, an arc-shaped prism, or the like.

[0024] As shown in Figure 2, the first rectifier section 213 is adjacent to the first recess 212 in the width direction DW and extends in the width direction DW. Current from the battery 12 flows through the first rectifier section 213. Furthermore, the first rectifier section 213 includes a first end 2131 and a second end 2132. The first end 2131 is the boundary between the first rectifier section 213 and the first recess 212. The second end 2132 is the end of the first rectifier section 213 opposite to the first end 2131, and here it is the boundary between the first rectifier section 213 and the other first recess 212.

[0025] The first resistor 31 is a shunt resistor and is formed in the shape of a plate from a copper alloy containing manganese and nickel. The first resistor 31 is connected to the first busbar 21 in the longitudinal direction DL by welding or the like. Furthermore, the electrical resistance of the first resistor 31 is greater than the electrical resistance of the first busbar 21. Also, as shown in Figure 3, the length of the first resistor 31 in the thickness direction DT is smaller than the length of the first busbar 21 in the thickness direction DT.

[0026] Returning to Figures 1 and 2, the second busbar section 22 is formed in a plate shape from copper or the like. The second busbar section 22 is connected to the opposite side of the first resistive section 31 from the first busbar section 21 via welding or the like in the longitudinal direction DL. Furthermore, the electrical resistance of the second busbar section 22 is lower than that of the first resistive section 31. Also, as shown in Figure 3, the length of the second busbar section 22 in the thickness direction DT is the same as the length of the first busbar section 21 in the thickness direction DT, and is greater than the length of the first resistive section 31 in the thickness direction DT. Here, "same" includes the manufacturing tolerance range.

[0027] Furthermore, as shown in Figures 1 and 2, the second busbar section 22 has a second side surface 221, a second recess 222, and a second rectifier section 223.

[0028] The second side surface 221 is a surface of the second busbar portion 22 that is perpendicular to the width direction DW, and corresponds to a surface of the second busbar portion 22 that intersects with the width direction DW.

[0029] The second recess 222 is recessed in the width direction DW from the second side surfaces 221 on both sides. Furthermore, the second recess 222 penetrates in the thickness direction DT. In addition, the second recess 222 is not in contact with the first resistive portion 31 and is separated from it. Note that, while there are two second recesses 222 here, the number is not limited to this. At least one second recess 222 is sufficient. Also, while the shape of the second recess 222 is a rectangular prism, the shape is not limited to this. The shape of the second recess 222 may be a polygonal prism, an arc-shaped prism, or the like.

[0030] As shown in Figure 2, the second rectifier section 223 is adjacent to the second recess 222 in the width direction DW and extends in the width direction DW. Current flows from the battery 12 through the first busbar section 21 and the first resistor section 31 to the second rectifier section 223. Furthermore, the second rectifier section 223 includes a third end 2231 and a fourth end 2232. The third end 2231 is the boundary between the second rectifier section 223 and the second recess 222. The fourth end 2232 is the end of the second rectifier section 223 opposite to the third end 2231, and here it is the boundary between the second rectifier section 223 and the other second recess 222.

[0031] The intermediate section 25 is formed in a plate shape from copper or the like. The intermediate section 25 is connected to the second busbar section 22 in the width direction DW. Furthermore, the electrical resistance of the intermediate section 25 is smaller than the electrical resistance of the first resistance section 31. In addition, the length of the intermediate section 25 in the thickness direction DT is the same as the length of the first busbar section 21 and the length of the second busbar section 22 in the thickness direction DT, and is greater than the length of the first resistance section 31 in the thickness direction DT.

[0032] The third busbar section 23 is formed in a plate shape from copper or the like. Furthermore, the third busbar section 23 is connected to the side of the intermediate section 25 opposite to the second busbar section 22 in the width direction DW, thus aligning with the second busbar section 22 in the width direction DW. Additionally, the electrical resistance of the third busbar section 23 is smaller than that of the first resistance section 31. Also, the length of the third busbar section 23 in the thickness direction DT is the same as the length of the first busbar section 21, the second busbar section 22, and the intermediate section 25 in the thickness direction DT. Therefore, the length of the third busbar section 23 in the thickness direction DT is greater than the length of the first resistance section 31 in the thickness direction DT.

[0033] Furthermore, as shown in Figures 1 and 2, the third busbar section 23 has a third side surface 231, a third recess 232, and a third rectifier section 233.

[0034] The third side surface 231 is a surface of the third busbar portion 23 that is perpendicular to the width direction DW and corresponds to a surface of the third busbar portion 23 that intersects with the width direction DW.

[0035] The third recess 232 is recessed in the width direction DW from both third sides 231. Furthermore, the third recess 232 penetrates in the thickness direction DT. In addition, the third recess 232 is not in contact with the second resistive portion 32, which will be described later, and is separated from it. Note that, while there are two third recesses 232 here, the number is not limited to this. At least one third recess 232 is sufficient. Also, while the shape of the third recess 232 is a rectangular prism, the shape is not limited to this. The shape of the third recess 232 may be a polygonal prism, an arc-shaped prism, or the like.

[0036] As shown in Figure 2, the third rectifier section 233 is adjacent to the third recess 232 in the width direction DW and extends in the width direction DW. Furthermore, current flows from the battery 12 through the first busbar section 21, the first resistor section 31, the second busbar section 22, and the intermediate section 25 to the third rectifier section 233. The third rectifier section 233 also includes a fifth end 2331 and a sixth end 2332. The fifth end 2331 is the boundary between the third rectifier section 233 and the third recess 232. The sixth end 2332 is the end of the third rectifier section 233 opposite to the fifth end 2331, and here it is the boundary between the third rectifier section 233 and the other third recess 232.

[0037] The second resistor 32 is a shunt resistor and is formed in a plate shape from a copper alloy containing manganese and nickel. The second resistor 32 is connected to the third busbar 23 in the longitudinal direction DL by welding or the like. Furthermore, the second resistor 32 is positioned apart from the first resistor 31 in the width direction DW. The electrical resistance of the second resistor 32 is the same as that of the first resistor 31 and is greater than the electrical resistances of the first busbar 21, the second busbar 22, the intermediate section 25, and the third busbar 23. Furthermore, the length of the second resistor 32 in the thickness direction DT is the same as the length of the first resistor 31 in the thickness direction DT. For this reason, the length of the second resistor 32 in the thickness direction DT is smaller than the length of the first busbar 21, the second busbar 22, and the intermediate section 25 in the thickness direction DT. Therefore, as shown in Figure 4, the length of the second resistive section 32 in the thickness direction DT is smaller than the length of the third busbar section 23 in the thickness direction DT. Note that the electrical resistance of the second resistive section 32 is the same as, but not limited to, the electrical resistance of the first resistive section 31. The electrical resistance of the second resistive section 32 may be different from the electrical resistance of the first resistive section 31. Also, the length of the second resistive section 32 in the thickness direction DT is the same as, but not limited to, the length of the first resistive section 31 in the thickness direction DT. The length of the second resistive section 32 in the thickness direction DT may be different from the length of the first resistive section 31 in the thickness direction DT.

[0038] Returning to Figures 1 and 2, the fourth busbar section 24 is formed in a plate shape from copper or the like. The fourth busbar section 24 is connected to the second resistive section 32 on the side opposite to the third busbar in the longitudinal direction DL. Furthermore, the fourth busbar section 24 is positioned apart from the first busbar section 21 in the width direction DW. The electrical resistance of the fourth busbar section 24 is smaller than that of the first resistive section 31 and the second resistive section 32. The length of the fourth busbar section 24 in the thickness direction DT is the same as the length of the third busbar section 23 in the thickness direction DT. Therefore, the length of the fourth busbar section 24 in the thickness direction DT is the same as the length of the first busbar section 21, the second busbar section 22, and the intermediate section 25 in the thickness direction DT. Furthermore, the length of the fourth busbar section 24 in the thickness direction DT is greater than the length of the first resistive section 31 in the thickness direction DT. Furthermore, as shown in Figure 4, the length of the fourth busbar portion 24 in the thickness direction DT is greater than the length of the second resistor portion 32 in the thickness direction DT.

[0039] In the thickness direction DT, the lengths of the first busbar section 21, the second busbar section 22, the intermediate section 25, the third busbar section 23, and the fourth busbar section 24 are the same, but this is not limited to the case. In the thickness direction DT, the lengths of the first busbar section 21, the second busbar section 22, the intermediate section 25, the third busbar section 23, and the fourth busbar section 24 may be different.

[0040] Furthermore, as shown in Figures 1 and 2, the fourth busbar section 24 has a second connection hole 240, a fourth side surface 241, a fourth recess 242, and a fourth rectifier section 243.

[0041] Bolts (not shown) are inserted into the second connection hole 240 and the inverter 14. This connects the fourth busbar section 24 to the inverter 14. Therefore, the battery 12, the first busbar section 21, the first resistor section 31, the second busbar section 22, the intermediate section 25, the third busbar section 23, the second resistor section 32, the fourth busbar section 24, and the inverter 14 are connected in series.

[0042] The fourth side surface 241 is a surface of the fourth busbar portion 24 that is perpendicular to the width direction DW, and corresponds to a surface of the fourth busbar portion 24 that intersects with the width direction DW.

[0043] The fourth recess 242 is recessed in the width direction DW from both sides of the fourth side surface 241. Furthermore, the fourth recess 242 penetrates in the thickness direction DT. In addition, the fourth recess 242 is not in contact with the second resistive portion 32 and is separated from it. Note that, while there are two fourth recesses 242 here, the number is not limited to this. At least one fourth recess 242 is sufficient. Also, while the shape of the fourth recess 242 is a rectangular prism, the shape is not limited to this. The shape of the fourth recess 242 may be a polygonal prism, an arc-shaped prism, or the like.

[0044] As shown in Figure 2, the fourth rectifier section 243 is adjacent to the fourth recess 242 in the width direction DW and extends in the width direction DW. Current flows from the battery 12 through the first busbar section 21, the first resistor section 31, the second busbar section 22, the intermediate section 25, the third busbar section 23, and the second resistor section 32 to the fourth rectifier section 243. Furthermore, the fourth rectifier section 243 includes a seventh end 2431 and an eighth end 2432. The seventh end 2431 is the boundary between the fourth rectifier section 243 and the fourth recess 242. The eighth end 2432 is the end of the fourth rectifier section 243 opposite to the seventh end 2431, and here it is the boundary between the fourth rectifier section 243 and the other fourth recess 242.

[0045] The first substrate 41 is a printed circuit board. As shown in Figures 1 and 3, the first substrate 41 has a first surface 411, a first back surface 412, a first through-hole 413, and a second through-hole 414.

[0046] The first surface 411 is a surface of the first substrate 41 that is perpendicular to the thickness direction DT and corresponds to a surface of the first substrate 41 that intersects with the thickness direction DT. Furthermore, the first surface 411 is located on the side of the first substrate 41 opposite to the first resistor 31.

[0047] The first back surface 412 is a surface of the first substrate 41 that is perpendicular to the thickness direction DT and corresponds to a surface of the first substrate 41 that intersects with the thickness direction DT. Furthermore, the first back surface 412 is the surface of the first substrate 41 located on the side of the first resistor 31, that is, the surface of the first substrate 41 that is opposite to the first surface 411.

[0048] The first through-hole 413 and the second through-hole 414 are holes that penetrate the first surface 411 and the first back surface 412, respectively.

[0049] The second substrate 42 is a printed circuit board. Furthermore, as shown in Figures 1 and 4, the second substrate 42 has a second front surface 421, a second back surface 422, a third through-hole 423, and a fourth through-hole 424.

[0050] The second surface 421 is a surface of the second substrate 42 that is perpendicular to the thickness direction DT and corresponds to a surface of the second substrate 42 that intersects with the thickness direction DT. Furthermore, the second surface 421 is located on the side of the second substrate 42 opposite to the second resistor 32.

[0051] The second back surface 422 is a surface of the second substrate 42 that is perpendicular to the thickness direction DT and corresponds to a surface of the second substrate 42 that intersects with the thickness direction DT. Furthermore, the second back surface 422 is located on the second resistive portion 32 side of the second substrate 42, that is, on the side of the second substrate 42 opposite to the first front surface 411.

[0052] The third through-hole 423 and the fourth through-hole 424 are holes that penetrate the second surface 421 and the second back surface 422, respectively.

[0053] The first connection part 51 consists of a land, pad, and solder, and as shown in Figure 3, it is connected to the portion of the first busbar 21 on the side of the first resistor 31 and to the first back surface 412. The second connection part 52 consists of a land, pad, and solder, and as shown in Figure 4, it is connected to the portion of the second busbar 22 on the side of the first resistor 31 and to the first back surface 412. The third connection part 53 consists of a land, pad, and solder, and as shown in Figure 4, it is connected to the portion of the third busbar 23 on the side of the second resistor 32 and to the second back surface 422. The fourth connection part 54 consists of a land, pad, and solder, and as shown in Figure 4, it is connected to the portion of the fourth busbar 24 on the side of the second resistor 32 and to the second back surface 422.

[0054] As shown in Figures 1 and 3, the first terminal portion 61 is positioned on the first substrate 41. A portion of the first terminal portion 61 is inserted into the first through-hole 413. Furthermore, the first terminal portion 61 protrudes from the first back surface 412. The portion of the first terminal portion 61 facing the first back surface 412 is connected to the first connection portion 51. Therefore, the first terminal portion 61 is connected to the first busbar portion 21 side of the first resistor portion 31 via the first connection portion 51 and the first busbar portion 21. As a result, the first terminal portion 61 outputs a signal corresponding to the voltage applied to the first busbar portion 21 side of the first resistor portion 31.

[0055] The second terminal section 62 is located on the first substrate 41. A portion of the second terminal section 62 is inserted into the second through-hole 414. Furthermore, the second terminal section 62 protrudes from the first back surface 412. The portion of the second terminal section 62 facing the first back surface 412 is connected to the second connection section 52. Therefore, the second terminal section 62 is connected to the second busbar section 22 side of the first resistor section 31 via the second connection section 52 and the second busbar section 22. As a result, the second terminal section 62 outputs a signal corresponding to the voltage applied to the second busbar section 22 side of the first resistor section 31.

[0056] As shown in Figures 1 and 4, the third terminal portion 63 is located on the second substrate 42. A portion of the third terminal portion 63 is inserted into the third through-hole 423. Furthermore, the third terminal portion 63 protrudes from the second back surface 422. The portion of the third terminal portion 63 on the second back surface 422 side is connected to the third connection portion 53. Therefore, the third terminal portion 63 is connected to the third busbar portion 23 side of the second resistor portion 32 via the third connection portion 53 and the third busbar portion 23. As a result, the third terminal portion 63 outputs a signal corresponding to the voltage applied to the third busbar portion 23 side of the second resistor portion 32.

[0057] The fourth terminal section 64 is located on the second substrate 42. A portion of the fourth terminal section 64 is inserted into the fourth through-hole 424. Furthermore, the fourth terminal section 64 protrudes from the second back surface 422. The portion of the fourth terminal section 64 facing the second back surface 422 is connected to the fourth connection section 54. Therefore, the fourth terminal section 64 is connected to the fourth busbar section 24 side of the second resistor section 32 via the fourth connection section 54 and the fourth busbar section 24. As a result, the fourth terminal section 64 outputs a signal corresponding to the voltage applied to the fourth busbar section 24 side of the second resistor section 32.

[0058] As shown in Figure 3, the first voltage detection point P1 is the contact point between the first terminal portion 61 and the first connection portion 51. The second voltage detection point P2 is the contact point between the second terminal portion 62 and the second connection portion 52. As shown in Figure 4, the third voltage detection point P3 is the contact point between the third terminal portion 63 and the third connection portion 53. The fourth voltage detection point P4 is the contact point between the fourth terminal portion 64 and the fourth connection portion 54.

[0059] Here, as shown in Figure 2, the surface passing through the first end 2131 and perpendicular to the width direction DW is defined as the first surface S1. The surface passing through the second end 2132 and perpendicular to the width direction DW is defined as the second surface S2. The surface passing through the third end 2231 and perpendicular to the width direction DW is defined as the third surface S3. The surface passing through the fourth end 2232 and perpendicular to the width direction DW is defined as the fourth surface S4. The surface passing through the fifth end 2331 and perpendicular to the width direction DW is defined as the fifth surface S5. The surface passing through the sixth end 2332 and perpendicular to the width direction DW is defined as the sixth surface S6. The surface passing through the seventh end 2431 and perpendicular to the width direction DW is defined as the seventh surface S7. The surface passing through the eighth end 2432 and perpendicular to the width direction DW is defined as the eighth surface S8. Also, the first surface S1 and the third surface S3 coincide. The second surface S2 and the fourth surface S4 coincide. Face 5 S5 and Face 7 S7 coincide. Face 6 S6 and Face 8 S8 coincide. Note that Face 1 S1 and Face 3 S3 do not necessarily have to coincide. Face 2 S2 and Face 4 S4 do not necessarily have to coincide. Face 5 S5 and Face 7 S7 do not necessarily have to coincide. Face 6 S6 and Face 8 S8 do not necessarily have to coincide.

[0060] Furthermore, the first voltage detection point P1 and the second voltage detection point P2 are located in the width direction DW, within the range from the first surface S1 to the second surface S2. Also, the first voltage detection point P1 and the second voltage detection point P2 are located in the width direction DW, within the range from the third surface S3 to the fourth surface S4. In addition, the third voltage detection point P3 and the fourth voltage detection point P4 are located in the width direction DW, within the range from the fifth surface S5 to the sixth surface S6. Furthermore, the third voltage detection point P3 and the fourth voltage detection point P4 are located in the width direction DW, within the range from the seventh surface S7 to the eighth surface S8. Figure 2 shows the positions of the first voltage detection point P1, the second voltage detection point P2, the third voltage detection point P3, and the fourth voltage detection point P4 as viewed from the thickness direction DT.

[0061] Returning to Figure 1, the first wiring 71 is located on the first surface 411 and connected to the portion of the first terminal 61 that is on the first surface 411 side. The second wiring 72 is located on the first surface 411 and connected to the portion of the second terminal 62 that is on the first surface 411 side. The third wiring 73 is located on the second surface 421 and connected to the portion of the third terminal 63 that is on the second surface 421 side. The fourth wiring 74 is located on the second surface 421 and connected to the portion of the fourth terminal 64 that is on the second surface 421 side.

[0062] The first pin 81 is located on the first surface 411 and is connected to the first wiring 71. Therefore, the first pin 81 is electrically connected to the first terminal portion 61 via the first wiring 71, and thus is electrically connected to the first terminal portion 61.

[0063] The second pin 82 is located on the first surface 411 and is connected to the second wiring 72. Therefore, the second pin 82 is connected to the second terminal portion 62 via the second wiring 72 and is electrically connected to the second terminal portion 62.

[0064] The third pin 83 is located on the second surface 421 and is connected to the third wiring 73. Therefore, the third pin 83 is electrically connected to the third terminal portion 63 via the third wiring 73.

[0065] The fourth pin 84 is located on the second surface 421 and is connected to the fourth wiring 74. Therefore, the fourth pin 84 is connected to the fourth terminal portion 64 via the fourth wiring 74, and thus is electrically connected to the fourth terminal portion 64.

[0066] The first thermistor 91 is located on the first surface 411 and outputs a signal corresponding to the temperature of the first resistive section 31. The second thermistor 92 is located on the first surface 411 at a different position from the first thermistor 91 and outputs a signal corresponding to the temperature of the first resistive section 31. The third thermistor 93 is located on the second surface 421 and outputs a signal corresponding to the temperature of the second resistive section 32. The fourth thermistor 94 is located on the second surface 421 at a different position from the third thermistor 93 and outputs a signal corresponding to the temperature of the second resistive section 32.

[0067] One of the two first thermistor pins 101 is connected to one electrode of the first thermistor 91 via wiring (not shown) located on the first surface 411. The other of the two first thermistor pins 101 is connected to the other electrode of the first thermistor 91 via wiring (not shown) located on the first surface 411.

[0068] One of the two second thermistor pins 102 is connected to one electrode of the second thermistor 92 via wiring (not shown) located on the first surface 411. The other of the two second thermistor pins 102 is connected to the other electrode of the second thermistor 92 via wiring (not shown) located on the first surface 411.

[0069] One of the two third thermistor pins 103 is connected to one electrode of the third thermistor 93 via wiring (not shown) located on the second surface 421. The other of the two third thermistor pins 103 is connected to the other electrode of the third thermistor 93 via wiring (not shown) located on the second surface 421.

[0070] One of the two fourth thermistor pins 104 is connected to one electrode of the fourth thermistor 94 via wiring (not shown) located on the second surface 421. The other of the two fourth thermistor pins 104 is connected to the other electrode of the fourth thermistor 94 via wiring (not shown) located on the second surface 421.

[0071] The first connector housing 111 is formed in a cylindrical shape from, for example, resin. The first connector housing 111 is also placed on the first substrate 41. Furthermore, the first connector housing 111 houses the first pin 81, the second pin 82, two first thermistor pins 101, and two second thermistor pins 102. As shown in Figure 3, when the first connector housing 111 is projected in the thickness direction DT, the projected first connector housing 111 does not overlap with the first resistor 31, the second resistor 32, the first connection 51, the second connection 52, the third connection 53, and the fourth connection 54. Furthermore, the first connector housing 111 projected in the thickness direction DT overlaps with the second busbar 22.

[0072] The second connector housing 112 is formed in a cylindrical shape from, for example, resin. The second connector housing 112 is also placed on the second substrate 42. Furthermore, the second connector housing 112 houses the third pin 83, the fourth pin 84, two third thermistor pins 103, and two fourth thermistor pins 104. As shown in Figure 4, when the second connector housing 112 is projected in the thickness direction DT, the projected second connector housing 112 is separated from the first resistor 31, the second resistor 32, the first connection 51, the second connection 52, the third connection 53, and the fourth connection 54 without overlapping. Furthermore, the second connector housing 112 projected in the thickness direction DT overlaps with the third busbar 23 in this case.

[0073] The calculation unit 120 is mainly composed of ICs and a microcontroller, and includes a CPU, ROM, flash memory, RAM, I / O, drive circuit, AD converter, low-pass filter, communication circuit, and bus lines connecting these components. As shown in Figure 1, the calculation unit 120 is located outside the first board 41 and the second board 42. However, the calculation unit 120 is not limited to being located outside the first board 41 and the second board 42; for example, it may be located on the first board 41 or the second board 42. IC stands for Integrated Circuit.

[0074] Furthermore, the calculation unit 120 is connected to the first pin 81, the second pin 82, the third pin 83, the fourth pin 84, the two first thermistor pins 101, the two second thermistor pins 102, the two third thermistor pins 103, and the two fourth thermistor pins 104. Therefore, the calculation unit 120 acquires the signal from the first terminal 61 via the first wiring 71 and the first pin 81. The calculation unit 120 acquires the signal from the second terminal 62 via the second wiring 72 and the second pin 82. The calculation unit 120 acquires the signal from the third terminal 63 via the third wiring 73 and the third pin 83. The calculation unit 120 acquires the signal from the fourth terminal 64 via the fourth wiring 74 and the fourth pin 84. Furthermore, the calculation unit 120 acquires a signal from the first thermistor 91 via wiring (not shown) and the pin 101 for the first thermistor. The calculation unit 120 acquires a signal from the second thermistor 92 via wiring (not shown) and the pin 102 for the second thermistor. The calculation unit 120 acquires a signal from the third thermistor 93 via wiring (not shown) and the pin 103 for the third thermistor. The calculation unit 120 acquires a signal from the fourth thermistor 94 via wiring (not shown) and the pin 104 for the fourth thermistor. Then, as will be described later, the calculation unit 120 calculates the current flowing from the battery 12 based on these acquired signals. Also, based on these acquired signals, the calculation unit 120 determines whether or not one of the first resistance unit 31 and the second resistance unit 32 is abnormal.

[0075] As described above, the motor generator system 10 is configured as described. Next, the detection and calculation of the current flowing from the battery 12 to the inverter 14 by the current detection device 20 will be explained.

[0076] Here, in order to explain the detection and calculation of current by the current detection device 20, the following terms are defined: The voltage applied to the first busbar section 21 side of the first resistor section 31 is defined as the first voltage V1. The voltage applied to the second busbar section 22 side of the first resistor section 31 is defined as the second voltage V2. The voltage applied to the third busbar section 23 side of the second resistor section 32 is defined as the third voltage V3. The voltage applied to the fourth busbar section 24 side of the second resistor section 32 is defined as the fourth voltage V4. The electrical resistance of the first resistor section 31 is defined as the first resistance R1. The electrical resistance of the second resistor section 32 is defined as the second resistance R2. The temperature of the first resistor section 31 is defined as the first temperature T1. The temperature of the second resistor section 32 is defined as the second temperature T2. The current from the battery 12 is defined as the battery current Ib.

[0077] When the battery 12 discharges, current flows from the battery 12 to the inverter 14 via the first busbar section 21, the first resistor section 31, the second busbar section 22, the intermediate section 25, the third busbar section 23, the second resistor section 32, and the fourth busbar section 24.

[0078] At this time, the first terminal 61 outputs a signal corresponding to the first voltage V1 to the calculation unit 120 via the first wiring 71 and the first pin 81. The second terminal 62 outputs a signal corresponding to the second voltage V2 to the calculation unit 120 via the second wiring 72 and the second pin 82. Furthermore, the third terminal 63 outputs a signal corresponding to the third voltage V3 to the calculation unit 120 via the third wiring 73 and the third pin 83. Furthermore, the fourth terminal 64 outputs a signal corresponding to the fourth voltage V4 to the calculation unit 120 via the fourth wiring 74 and the fourth pin 84.

[0079] Furthermore, at this time, the first thermistor 91 outputs a signal corresponding to the first temperature T1 to the calculation unit 120 via wiring (not shown) and the first thermistor pin 101. Also, the second thermistor 92 outputs a signal corresponding to the first temperature T1 to the calculation unit 120 via wiring (not shown) and the second thermistor pin 102. Furthermore, the third thermistor 93 outputs a signal corresponding to the second temperature T2 to the calculation unit 120 via wiring (not shown) and the third thermistor pin 103. Also, the fourth thermistor 94 outputs a signal corresponding to the second temperature T2 to the calculation unit 120 via wiring (not shown) and the fourth thermistor pin 104.

[0080] At this time, the calculation unit 120 acquires the first voltage V1, the second voltage V2, the third voltage V3, the fourth voltage V4, the first temperature T1, and the second temperature T2. The calculation unit 120 also calculates the corrected first resistance R1_C by correcting the first resistance R1 based on the acquired first temperature T1 and the temperature coefficient of resistance of the first resistance unit 31 which is stored in advance. Furthermore, the calculation unit 120 calculates the corrected second resistance R2_C by correcting the second resistance R2 based on the acquired second temperature T2 and the temperature coefficient of resistance of the second resistance unit 32 which is stored in advance.

[0081] The calculation unit 120 then calculates the battery current Ib based on the first voltage V1, second voltage V2, third voltage V3, and fourth voltage V4 obtained above, and the corrected first resistance R1_C and corrected second resistance R2_C calculated above.

[0082] For example, the calculation unit 120 calculates the battery current Ib by dividing the difference between the first voltage V1 and the fourth voltage V4 by the sum of the corrected first resistor R1_C and the corrected second resistor R2_C, as shown in the following relational equation (1-1).

[0083] Furthermore, for example, the calculation unit 120 calculates the battery current Ib by dividing the difference between the first voltage V1 and the second voltage V2 by the corrected first resistor R1_C, as shown in the following relational equation (1-2).

[0084] Furthermore, for example, the calculation unit 120 calculates the battery current Ib by dividing the difference between the third voltage V3 and the fourth voltage V4 by the corrected second resistor R2_C, as shown in the following relational equation (1-3).

[0085] Furthermore, for example, the calculation unit 120 calculates the battery current Ib by dividing the difference between the first voltage V1 and the third voltage V3 by the corrected first resistor R1_C, as shown in the following relational equation (1-4).

[0086] Furthermore, for example, the calculation unit 120 calculates the battery current Ib by dividing the difference between the second voltage V2 and the fourth voltage V4 by the corrected second resistor R2_C, as shown in the following relational equation (1-5).

[0087] Ib=(V1-V4) / (R1_C+R2_C) ···(1-1) Ib = (V1 - V2) / R1_C ... (1 - 2) Ib = (V3 - V4) / R2_C ... (1 - 3) Ib = (V1 - V3) / R1_C ... (1 - 4) Ib = (V2 - V4) / R2_C ... (1 - 5)

[0088] In the above calculation example, to make the calculation of the battery current Ib easier to understand, the calculation unit 120 calculates the battery current Ib by assuming that the electrical resistance of the first busbar section 21, the second busbar section 22, the intermediate section 25, the third busbar section 23, and the fourth busbar section 24 is zero. However, the calculation unit 120 is not limited to calculating the battery current Ib by assuming that the electrical resistance of the first busbar section 21, the second busbar section 22, the intermediate section 25, the third busbar section 23, and the fourth busbar section 24 is zero. The calculation unit 120 may also calculate the battery current Ib by taking into account the electrical resistance of the first busbar section 21, the second busbar section 22, the intermediate section 25, the third busbar section 23, and the fourth busbar section 24.

[0089] As described above, the current detection device 20 detects and calculates the battery current Ib. Next, we will explain how the current detection device 20 determines whether one of the first resistance section 31 and the second resistance section 32 is abnormal.

[0090] Specifically, the calculation unit 120 determines whether one of the first resistance unit 31 and the second resistance unit 32 is abnormal based on the first voltage V1, second voltage V2, third voltage V3, fourth voltage V4 and the corrected first resistance R1_C and corrected second resistance R2_C.

[0091] Here, for example, as shown in relation (1-2) above, the battery current Ib calculated by dividing the difference between the first voltage V1 and the second voltage V2 by the corrected first resistor R1_C is defined as the first battery current Ib1. Also, as shown in relation (1-3) above, the battery current Ib calculated by dividing the difference between the third voltage V3 and the fourth voltage V4 by the corrected second resistor R2_C is defined as the second battery current Ib2.

[0092] The calculation unit 120 then calculates the absolute value of the difference between the first battery current Ib1 and the second battery current Ib2, |Ib1-Ib2|.

[0093] Furthermore, let's assume that the first resistor 31 and the second resistor 32 are normal. In this case, the first battery current Ib1 and the second battery current Ib2 are the same, so the absolute value |Ib1-Ib2| is 0. Next, let's assume that the first resistor 31 is abnormal and the second resistor 32 is normal. In this case, the corrected first resistor R1_C becomes an abnormal value, so the first battery current Ib1 is different from the second battery current Ib2, and the absolute value |Ib1-Ib2| is larger than when the first resistor 31 and the second resistor 32 are normal. Next, let's assume that the first resistor 31 is normal and the second resistor 32 is abnormal. In this case, the corrected second resistor R2_C becomes an abnormal value, and since the second battery current Ib2 is different from the first battery current Ib1, the absolute value |Ib1-Ib2| becomes larger compared to when the first resistor 31 and the second resistor 32 are functioning normally.

[0094] Therefore, the calculation unit 120 determines whether the absolute value |Ib1-Ib2| is greater than or equal to the threshold ΔIb_th, as shown in the following relational expression (1-6). Based on this, the calculation unit 120 determines whether one of the first resistor 31 and the second resistor 32 is abnormal. The threshold ΔIb_th is set through experiments, simulations, etc., so that it can be determined whether one of the first resistor 31 and the second resistor 32 is abnormal.

[0095] |Ib1-Ib2|≧ΔIb_th ···(1-6)

[0096] When the absolute value |Ib1-Ib2| is greater than or equal to the threshold ΔIb_th, the calculation unit 120 determines that one of the first resistor 31 and the second resistor 32 is abnormal because the first battery current Ib1 and the second battery current Ib2 are significantly different. When the absolute value |Ib1-Ib2| is less than the threshold ΔIb_th, the calculation unit 120 determines that the first resistor 31 and the second resistor 32 are normal because the first battery current Ib1 and the second battery current Ib2 are almost the same.

[0097] In the above example, the first battery current Ib1 is the battery current Ib shown in relational expression (1-2), and the second battery current Ib2 is the battery current Ib shown in relational expression (1-3). However, it is not limited to the first battery current Ib1 being the battery current Ib shown in relational expression (1-2) and the second battery current Ib2 being the battery current Ib shown in relational expression (1-3). For example, the first battery current Ib1 may be the battery current Ib shown in relational expression (1-4), and the second battery current Ib2 may be the battery current Ib shown in relational expression (1-5). Also, the first battery current Ib1 may be the battery current Ib shown in relational expression (1-1), and the second battery current Ib2 may be the battery current Ib shown in relational expressions (1-2) to (1-5). Furthermore, in the above example of determination, in order to make the abnormality determination easier to understand, the calculation unit 120 performs the abnormality determination by considering the electrical resistance of the first busbar section 21, the second busbar section 22, the intermediate section 25, the third busbar section 23, and the fourth busbar section 24 as zero. However, the calculation unit 120 is not limited to performing the abnormality determination by considering the electrical resistance of the first busbar section 21, the second busbar section 22, the intermediate section 25, the third busbar section 23, and the fourth busbar section 24 as zero. The calculation unit 120 may also perform the abnormality determination by taking into account the electrical resistance of the first busbar section 21, the second busbar section 22, the intermediate section 25, the third busbar section 23, and the fourth busbar section 24.

[0098] As described above, the current detection device 20 determines whether one of the first resistance section 31 and the second resistance section 32 is abnormal. Next, the manufacturing method of the current detection device 20 of this embodiment will be described with reference to the flowchart in Figure 5. The manufacturing method of the current detection device 20 includes a preparation step S100, a connection step S102, a molding step S104, and an assembly step S106.

[0099] In preparation step S100, as shown in Figure 6, a first member 141, a resistive member 150, and a second member 142 are prepared. The first member 141 is formed in the shape of a plate from copper or the like. The length of the first member 141 in the width direction DW is relatively large. The resistive member 150 is formed in the shape of a plate from a copper alloy containing manganese and nickel or the like. Furthermore, the length of the resistive member 150 in the width direction DW is the same as the length of the first member 141 in the width direction DW. The second member 142 is formed in the shape of a plate from copper or the like. Furthermore, the length of the second member 142 in the width direction DW is the same as the length of the first member 141 and the length of the resistive member 150 in the width direction DW.

[0100] Next, in connection step S102, the first member 141 is connected to the resistance member 150 in the longitudinal direction DL by welding or the like, and the second member 142 is connected to the opposite side of the resistance member 150 from the first member 141 in the longitudinal direction DL. As a result, as shown in Figure 7, a connected body is formed in which the first member 141, the resistance member 150, and the second member 142 are integrated.

[0101] Next, in molding step S104, as shown in Figures 8 and 9, the first member 141, the resistance member 150, and the second member 142, which were integrated by the connecting step S102, are punched out in the thickness direction DT by the first punch 151 and the second punch 152. Furthermore, the first member 141, the resistance member 150, and the second member 142, which were integrated by the connecting step S102, are punched out in the thickness direction DT by the third punch 153 and the fourth punch 154.

[0102] Multiple first punches 151 are arranged in the width direction DW with gaps between them. Furthermore, the length of the first punches 151 in the longitudinal direction DL is greater than the length of the connecting body in the longitudinal direction DL. Therefore, the punching action of the first punches 151 divides the connecting body into multiple pieces, resulting in multiple pieces being arranged in the width direction DW.

[0103] Multiple second punches 152 are arranged at intervals in the width direction DW. First punches 151 are positioned between adjacent second punches 152. Furthermore, the second punches 152 punch out parts of the integrated first member 141, resistance member 150, and second member 142, specifically the first member 141 and resistance member 150, as well as a portion of the second member 142. As a result, the first member 141 becomes the first busbar section 21 and the fourth busbar section 24. The resistance member 150 becomes the first resistance section 31 and the second resistance section 32. The second member 142 becomes the second busbar section 22, the intermediate section 25, and the third busbar section 23. Therefore, the first busbar section 21, the first resistance section 31, the second busbar section 22, the intermediate section 25, the third busbar section 23, and the fourth busbar section 24 are formed.

[0104] The third punch 153 is formed in a shape corresponding to the first connection hole 210 and the second connection hole 240. Therefore, the first connection hole 210 is formed in the first busbar portion 21 by punching with the third punch 153. In addition, the second connection hole 240 is formed in the fourth busbar portion 24.

[0105] The fourth punch 154 is formed in a shape corresponding to the first recess 212, the second recess 222, the third recess 232, and the fourth recess 242. Therefore, the first recess 212 is formed in the first busbar portion 21 by punching with the fourth punch 154. The second recess 222 is formed in the second busbar portion 22. Furthermore, the third recess 232 is formed in the third busbar portion 23. And the fourth recess 242 is formed in the fourth busbar portion 24.

[0106] Next, in assembly step S106, a first connection portion 51 is formed on the first back surface 412 by soldering or the like, and the first connection portion 51 is connected to the portion of the first busbar portion 21 on the side of the first resistor portion 31 and to the first terminal portion 61. As a result, the first terminal portion 61 is connected to the first busbar portion 21 side of the first resistor portion 31 via the first connection portion 51 and the first busbar portion 21. Therefore, the first terminal portion 61 is able to output a signal corresponding to the first voltage V1. Furthermore, the first voltage detection point P1 is located in the width direction DW, within the range from the first surface S1 to the second surface S2. In addition, the first voltage detection point P1 is located in the width direction DW, within the range from the third surface S3 to the fourth surface S4.

[0107] Furthermore, a second connection portion 52 is formed on the first back surface 412 by soldering or the like, and the second connection portion 52 is connected to the portion of the second busbar portion 22 on the side of the first resistor portion 31 and to the second terminal portion 62. As a result, the second terminal portion 62 is connected to the side of the first resistor portion 31 on the second busbar portion 22 via the second connection portion 52 and the second busbar portion 22. Therefore, the second terminal portion 62 is able to output a signal corresponding to the second voltage V2. In addition, the second voltage detection point P2 is located in the width direction DW, within the range from the first surface S1 to the second surface S2. Furthermore, the second voltage detection point P2 is located in the width direction DW, within the range from the third surface S3 to the fourth surface S4.

[0108] Furthermore, a third connection portion 53 is formed on the second back surface 422 by soldering or the like, and the third connection portion 53 is connected to the portion of the third busbar portion 23 on the second resistor portion 32 side and to the third terminal portion 63. As a result, the third terminal portion 63 is connected to the third busbar portion 23 side of the second resistor portion 32 via the third connection portion 53 and the third busbar portion 23. Therefore, the third terminal portion 63 is able to output a signal corresponding to the third voltage V3. In addition, the third voltage detection point P3 is located in the width direction DW in the range from the fifth surface S5 to the sixth surface S6. Furthermore, the third voltage detection point P3 is located in the width direction DW in the range from the seventh surface S7 to the eighth surface S8.

[0109] Furthermore, a fourth connection portion 54 is formed on the second back surface 422 by soldering or the like, and the fourth connection portion 54 is connected to the portion of the fourth busbar portion 24 on the second resistor portion 32 side and to the fourth terminal portion 64. As a result, the fourth terminal portion 64 is connected to the fourth busbar portion 24 side of the second resistor portion 32 via the fourth connection portion 54 and the fourth busbar portion 24. Therefore, the fourth terminal portion 64 is able to output a signal corresponding to the fourth voltage V4. In addition, the fourth voltage detection point P4 is located in the width direction DW, within the range from the fifth surface S5 to the sixth surface S6. Furthermore, the fourth voltage detection point P4 is located in the width direction DW, within the range from the seventh surface S7 to the eighth surface S8.

[0110] Furthermore, the first substrate 41 is equipped with a first pin 81, a second pin 82, a first thermistor 91, a second thermistor 92, two first thermistor pins 101, and two second thermistor pins 102. The second substrate 42 is equipped with a third pin 83, a fourth pin 84, a third thermistor 93, a fourth thermistor 94, two third thermistor pins 103, and two fourth thermistor pins 104.

[0111] Furthermore, suppose the first connector housing 111, which houses the first pin 81, the second pin 82, the two first thermistor pins 101, and the two second thermistor pins 102, is projected in the thickness direction DT. The first connector housing 111 is positioned such that this projected first connector housing 111 does not overlap with the first resistor 31, the second resistor 32, the first connection 51, the second connection 52, the third connection 53, and the fourth connection 54.

[0112] Furthermore, assume that the second connector housing 112, which houses the third pin 83, the fourth pin 84, the two third thermistor pins 103, and the two fourth thermistor pins 104, is projected in the thickness direction DT. The second connector housing 112 is positioned such that the projected second connector housing 112 does not overlap with the first resistor 31, the second resistor 32, the first connection 51, the second connection 52, the third connection 53, and the fourth connection 54.

[0113] Furthermore, the calculation unit 120 is connected to the first pin 81, the second pin 82, the third pin 83, the fourth pin 84, the two first thermistor pins 101, the two second thermistor pins 102, the two third thermistor pins 103, and the two fourth thermistor pins 104. This completes the current detection device 20.

[0114] As described above, the current detection device 20 is manufactured. Next, we will explain how the current detection device 20 enables easy current detection while suppressing a decrease in current detection accuracy.

[0115] Here, as described in Patent Document 1, a measuring resistor is known that has multiple pairs of voltage measuring contacts for measuring the voltage drop across the ends of a resistive element. In this measuring resistor, multiple voltage values ​​are measured simultaneously at multiple pairs of voltage measuring contacts, and the voltage values ​​are derived from these measurements by a weighted average, thereby quantitatively compensating for non-uniformity in current density. In the measuring resistor described in Patent Document 1, the accuracy of current detection is improved because multiple voltage values ​​are used and non-uniformity in current density is quantitatively compensated for. However, because multiple voltage values ​​are used, the calculation of current becomes complex. This increases the calculation load.

[0116] In contrast, the current detection device 20 of this embodiment comprises a first busbar section 21, a first resistor section 31, a second busbar section 22, a first terminal section 61, and a second terminal section 62. The current detection device 20 also comprises a first substrate 41, a first connection section 51, a second connection section 52, a first voltage detection point P1, and a second voltage detection point P2. The first substrate 41 has the first terminal section 61 and the second terminal section 62 arranged on it. The first connection section 51 is connected to the first substrate 41, the first resistor section 31 side of the first busbar section 21, and the first terminal section 61. The second connection section 52 is connected to the second substrate 42, the first resistor section 31 side of the second busbar section 22, and the second terminal section 62. The first voltage detection point P1 is the contact point between the first terminal section 61 and the first connection section 51. The second voltage detection point P2 is the contact point between the second terminal portion 62 and the second connection portion 52. The first voltage detection point P1 corresponds to the first detection point, and the second voltage detection point P2 corresponds to the second detection point.

[0117] Furthermore, the first busbar section 21 has a first side surface 211, a first recess 212, and a first rectifier section 213. The first side surface 211 intersects with the width direction DW. The first recess 212 is recessed from the first side surface 211 in the width direction DW. The first rectifier section 213 extends in the width direction DW while being adjacent to the first recess 212, and current from the battery 12 flows through it. Furthermore, the first rectifier section 213 includes a first end 2131 and a second end 2132.

[0118] Furthermore, as described above, the plane passing through the first end 2131 and perpendicular to the width direction DW is defined as the first plane S1. In addition, the plane passing through the second end 2132 and perpendicular to the width direction DW is defined as the second plane S2. The first voltage detection point P1 and the second voltage detection point P2 are located in the width direction DW within the range from the first plane S1 to the second plane S2.

[0119] The range of current flowing through the first rectifier 213 is smaller than that of the parts of the first busbar 21 that are not the first rectifier 213. As a result, the current flowing through the first rectifier 213 is rectified. Therefore, the current density of the first rectifier 213 increases. In addition, the first voltage detection point P1 and the second voltage detection point P2 are arranged in the width direction DW within the range from the first surface S1 to the second surface S2. As a result, signals corresponding to the voltage that corresponds to the increased current density due to the first rectifier 213 are output from the first terminal section 61 and the second terminal section 62. Therefore, the sensitivity to the battery current Ib is improved. Consequently, the signal-to-noise ratio for the battery current Ib is improved, and the decrease in current detection accuracy is suppressed. Furthermore, since it is no longer necessary to measure multiple pairs of voltages, the complexity of calculation is suppressed. Therefore, current detection can be performed simply, and the decrease in current detection accuracy is suppressed.

[0120] Furthermore, when the connection direction between the battery 12 and the first busbar section 21 is in the longitudinal direction DL, the direction of the current flowing from the battery 12 to the first busbar section 21 is in the longitudinal direction DL. Moreover, when the connection direction between the battery 12 and the first busbar section 21 is in the width direction DW, the direction of the current flowing from the battery 12 to the first busbar section 21 is in the width direction DW. Therefore, if the connection direction between the battery 12 and the first busbar section 21 is changed, the direction of the current flowing from the battery 12 to the first busbar section 21 is changed. Moreover, if the direction of the current flowing from the battery 12 to the first busbar section 21 is changed, the current distribution within the first busbar section 21 changes. If the current distribution within the first busbar section 21 changes, the current detection accuracy decreases. Thus, if the connection direction between the battery 12 and the first busbar section 21 is changed, the current distribution within the first busbar section 21 changes, and therefore the current detection accuracy decreases.

[0121] In contrast, in the current detection device 20 of this embodiment, as described above, the current flowing through the first rectifier unit 213 is rectified, and the current density of the first rectifier unit 213 increases. This improves the sensitivity to the battery current Ib. Therefore, the signal-to-noise ratio for the battery current Ib is improved, and a decrease in current detection accuracy is suppressed. Thus, even if the connection direction between the battery 12 and the first busbar unit 21 is changed, a decrease in current detection accuracy is suppressed.

[0122] Furthermore, the current detection device 20 of the first embodiment also provides the following effects.

[0123] [1-1] The second busbar section 22 has a second side surface 221, a second recess 222, and a second rectifier section 223. The second side surface 221 intersects with the width direction DW. The second recess 222 is recessed from the second side surface 221 in the width direction DW. The second rectifier section 223 extends in the width direction DW while being adjacent to the second recess 222, and current flows from the battery 12 through the first busbar section 21 and the first resistor section 31. Furthermore, the second rectifier section 223 includes a third end 2231 and a fourth end 2232.

[0124] Furthermore, as described above, the plane passing through the third end 2231 and perpendicular to the width direction DW is defined as the third plane S3. In addition, the plane passing through the fourth end 2232 and perpendicular to the width direction DW is defined as the fourth plane S4. The first voltage detection point P1 and the second voltage detection point P2 are located in the width direction DW within the range from the third plane S3 to the fourth plane S4.

[0125] This allows for easy current detection, as described above, while suppressing a decrease in current detection accuracy.

[0126] [1-2] The current detection device 20 comprises a third busbar section 23, a second resistor section 32, a fourth busbar section 24, a third terminal section 63, and a fourth terminal section 64. The current detection device 20 also comprises a second circuit board 42, a third connection section 53, a fourth connection section 54, a third voltage detection point P3, and a fourth voltage detection point P4. The third terminal section 63 and the fourth terminal section 64 are arranged on the second circuit board 42. The third connection section 53 is connected to the second circuit board 42, the second resistor section 32 side of the third busbar section 23, and the third terminal section 63. The fourth connection section 54 is connected to the second circuit board 42, the second resistor section 32 side of the fourth busbar section 24, and the fourth terminal section 64. The third voltage detection point P3 is the contact point between the third terminal section 63 and the third connection section 53. The fourth voltage detection point P4 is the contact point between the fourth terminal 64 and the fourth connection 54. The third voltage detection point P3 corresponds to the third detection point. The fourth voltage detection point P4 corresponds to the fourth detection point.

[0127] Furthermore, the third busbar section 23 has a third side surface 231, a third recess 232, and a third rectifier section 233. The third side surface 231 intersects with the width direction DW. The third recess 232 is recessed from the third side surface 231 in the width direction DW. The third rectifier section 233 extends in the width direction DW while being adjacent to the third recess 232, and current flows from the battery 12 through the first busbar section 21, the first resistor section 31, the second busbar section 22, and the intermediate section 25. In addition, the third rectifier section 233 includes a fifth end 2331 and a sixth end 2332.

[0128] Furthermore, as described above, the plane passing through the fifth end 2331 and perpendicular to the width direction DW is defined as the fifth plane S5. Also, the plane passing through the sixth end 2332 and perpendicular to the width direction DW is defined as the sixth plane S6. The third voltage detection point P3 and the fourth voltage detection point P4 are located in the width direction DW within the range from the fifth plane S5 to the sixth plane S6.

[0129] This allows for easy current detection, as described above, while suppressing a decrease in current detection accuracy.

[0130] [1-3] The fourth busbar section 24 has a fourth side surface 241, a fourth recess 242, and a fourth rectifier section 243. The fourth side surface 241 intersects with the width direction DW. The fourth recess 242 is recessed from the fourth side surface 241 in the width direction DW. The fourth rectifier section 243 extends in the width direction DW while being adjacent to the fourth recess 242, and current flows from the battery 12 through the first busbar section 21, the first resistor section 31, the second busbar section 22, the intermediate section 25, the third busbar section 23, and the second resistor section 32. Furthermore, the fourth rectifier section 243 includes a seventh end 2431 and an eighth end 2432.

[0131] Furthermore, as described above, the plane passing through the seventh end 2431 and perpendicular to the width direction DW is defined as the seventh plane S7. Also, the plane passing through the eighth end 2432 and perpendicular to the width direction DW is defined as the eighth plane S8. The third voltage detection point P3 and the fourth voltage detection point P4 are located in the width direction DW within the range from the seventh plane S7 to the eighth plane S8.

[0132] As a result, current detection can be easily performed, as described above, and a decrease in current detection accuracy is suppressed. Furthermore, even if the connection direction between the fourth busbar section 24 and the inverter 14 is changed, a decrease in current detection accuracy is suppressed.

[0133] [1-4] The first recess 212 is not in contact with the first resistive portion 31 and is separated from the first resistive portion 31. This makes it less likely for the first resistive portion 31 to be damaged when forming the first recess 212. The second recess 222 is not in contact with the first resistive portion 31 and is separated from the first resistive portion 31. This makes it less likely for the first resistive portion 31 to be damaged when forming the second recess 222. Furthermore, the third recess 232 is not in contact with the second resistive portion 32 and is separated from the second resistive portion 32. This makes it less likely for the second resistive portion 32 to be damaged when forming the third recess 232. Furthermore, the fourth recess 242 is not in contact with the second resistive portion 32 and is separated from the second resistive portion 32. This makes it less likely for the second resistive portion 32 to be damaged when forming the fourth recess 242.

[0134] [1-5] In the resistor device described in Japanese Patent Publication No. 2005-17293, if a failure occurs in the first shunt resistor, which is a resistor, due to changes over time, the battery current will not be measured correctly. Also, if a failure occurs in the second shunt resistor, which is a resistor, due to changes over time, the generator current will not be measured correctly. Furthermore, it will not be determined that one of the two resistors is abnormal.

[0135] In contrast, the current detection device 20 of this embodiment comprises a first busbar section 21, a first resistance section 31, a second busbar section 22, an intermediate section 25, a third busbar section 23, a second resistance section 32, and a fourth busbar section 24. The current detection device 20 also comprises a first terminal section 61, a second terminal section 62, a third terminal section 63, a fourth terminal section 64, and a calculation unit 120. The calculation unit 120 calculates the battery current Ib based on the first voltage V1, the second voltage V2, the third voltage V3, and the fourth voltage V4, and the first resistance R1 and the second resistance R2, and determines whether one of the first resistance section 31 and the second resistance section 32 is abnormal. The battery current Ib is the current that flows from the battery 12 through the first busbar section 21, the first resistor section 31, the second busbar section 22, the intermediate section 25, the third busbar section 23, and the second resistor section 32 to the fourth busbar section 24, and corresponds to the device current. The battery 12 corresponds to an external device.

[0136] As a result, it is determined that one of the first resistor 31 and the second resistor 32 is abnormal, making it possible to determine that one of the two resistors is abnormal. Therefore, the redundancy of the current detection device 20 is improved.

[0137] Furthermore, even if the first resistor 31 fails, the second resistor 32 can be used, for example, by using the third voltage V3, the fourth voltage V4, and the second resistor R2, detection of the battery current Ib becomes possible. Moreover, even if the second resistor 32 fails, the first resistor 31 can be used, for example, by using the first voltage V1, the second voltage V2, and the first resistor R1, detection of the battery current Ib becomes possible. Therefore, the redundancy of the current detection device 20 is improved.

[0138] [1-6] The calculation unit 120 calculates the battery current Ib based on a value relating to the difference between the first voltage V1 and the fourth voltage V4, for example, V1-V4, and a value relating to the sum of the first resistor R1 and the second resistor R2, for example, R1_C+R2_C.

[0139] As a result, the resistance value used to calculate the battery current Ib is greater than that of the first resistor R1. Also, the resistance value used to calculate the battery current Ib is greater than that of the second resistor R2. Therefore, when current is flowing from the battery 12, the voltage difference is divided by a larger value compared to when only the first resistor R1 is used or when only the second resistor R2 is used. Consequently, the range of voltage differences for which the current can be displayed becomes larger, and the resolution for the battery current Ib increases.

[0140] Furthermore, when no battery current Ib is flowing, the voltage difference is divided by a larger value compared to when only the first resistor R1 is used or when only the second resistor R2 is used. Therefore, when no battery current Ib is flowing, the zero-point error of the battery current Ib, i.e., the offset error, is smaller compared to when only the first resistor R1 is used or when only the second resistor R2 is used.

[0141] [1-7] The calculation unit 120 calculates the battery current Ib based on a value relating to the difference between the first voltage V1 and the second voltage V2, for example, V1-V2, and a value relating to the first resistor R1, for example, the corrected first resistor R1_C.

[0142] As a result, compared to calculating the battery current Ib using the difference between the first voltage V1 and the third voltage V3, the influence of voltage drops due to the second busbar section 22, the intermediate section 25, and the third busbar section 23 is reduced, and the battery current Ib is calculated more easily.

[0143] [1-8] The calculation unit 120 calculates the battery current Ib based on a value relating to the difference between the third voltage V3 and the fourth voltage V4, for example, V3-V4, and a value relating to the second resistor R2, for example, the corrected second resistor R2_C.

[0144] This reduces the influence of voltage drops caused by the second busbar section 22, the intermediate section 25, and the third busbar section 23, compared to calculating the battery current Ib using the difference between the second voltage V2 and the fourth voltage V4. Therefore, the calculation of the battery current Ib becomes easier.

[0145] [1-9] The current detection device 20 comprises a first substrate 41 and a second substrate 42. The first substrate 41 has a first terminal section 61 and a second terminal section 62. The second substrate 42 has a third terminal section 63 and a fourth terminal section 64.

[0146] As a result, even if the first substrate 41 is damaged, the third terminal section 63 and the fourth terminal section 64, which are located on the second substrate 42 and are different from the first substrate 41, are less likely to be damaged. Furthermore, even if the first terminal section 61 and the second terminal section 62 are damaged due to damage to the first substrate 41, battery current Ib can still be detected by using the third terminal section 63 and the fourth terminal section 64. Moreover, even if the second substrate 42 is damaged, the first terminal section 61 and the second terminal section 62, which are located on the first substrate 41 and are different from the second substrate 42, are less likely to be damaged. Furthermore, even if the third terminal section 63 and the fourth terminal section 64 are damaged due to damage to the second substrate 42, battery current Ib can still be detected by using the first terminal section 61 and the second terminal section 62. Thus, the redundancy of the current detection device 20 is improved.

[0147] [1-10] The current detection device 20 comprises a first pin 81, a second pin 82, a third pin 83, a fourth pin 84, a first connector housing 111, and a second connector housing 112. The first connector housing 111 houses the first pin 81 and the second pin 82. The second connector housing 112 houses the third pin 83 and the fourth pin 84.

[0148] As a result, even if the first connector housing 111 is damaged, the third pin 83 and fourth pin 84, which are housed in the second connector housing 112 (which is different from the first connector housing 111), are less likely to be damaged. Furthermore, even if the first pin 81 and second pin 82 are damaged due to damage to the first connector housing 111, battery current Ib can still be detected using the third pin 83 and fourth pin 84. Moreover, even if the second connector housing 112 is damaged, the first pin 81 and second pin 82, which are housed in the first connector housing 111 (which is different from the second connector housing 112), are less likely to be damaged. Furthermore, even if the third pin 83 and fourth pin 84 are damaged due to damage to the second connector housing 112, battery current Ib can still be detected using the first pin 81 and second pin 82. Therefore, the redundancy of the current detection device 20 is improved.

[0149] [1-11] Here, the first resistor 31 and the second resistor 32 generate heat due to the battery current Ib. This heat from the first resistor 31 and the second resistor 32 is transferred to the first connector housing 111, which may cause damage to the first connector housing 111.

[0150] Therefore, when the first connector housing 111 is projected in the thickness direction DT, the projected first connector housing 111 is separated from the first resistor 31 and the second resistor 32 without overlapping.

[0151] As a result, the first connector housing 111, when projected in the thickness direction DT, is separated from the first and second resistors 31 and 32, compared to the case where the first connector housing 111 overlaps with the first and second resistors 31 and 32. Therefore, heat from the first and second resistors 31 and 32 is less likely to be transferred to the first connector housing 111. Consequently, damage to the first connector housing 111 is suppressed.

[0152] [1-12] In addition, heat from the first resistor 31 and the second resistor 32 may be transferred to the second connector housing 112, which could cause damage to the second connector housing 112.

[0153] Therefore, when the second connector housing 112 is projected in the thickness direction DT, the projected second connector housing 112 is separated from the first resistor 31 and the second resistor 32 without overlapping.

[0154] As a result, compared to the case where the second connector housing 112 projected in the thickness direction DT overlaps with the first resistor 31 and the second resistor 32, the second connector housing 112 is separated from the first resistor 31 and the second resistor 32. Therefore, heat from the first resistor 31 and the second resistor 32 is less likely to be transferred to the second connector housing 112. Consequently, damage to the second connector housing 112 is suppressed.

[0155] [1-13] The current detection device 20 includes a first thermistor 91 and a second thermistor 92. The calculation unit 120 corrects the first resistance R1 based on the first temperature T1. The first thermistor 91 corresponds to the first temperature detection unit. The second thermistor 92 corresponds to the second temperature detection unit.

[0156] As a result, even if the first thermistor 91 fails, the calculation unit 120 can correct the first resistance R1 using the first temperature T1 detected by the second thermistor 92. Furthermore, even if the second thermistor 92 fails, the calculation unit 120 can correct the first resistance R1 using the first temperature T1 detected by the first thermistor 91. Thus, the redundancy of the current detection device 20 is improved.

[0157] [1-14] The current detection device 20 includes a third thermistor 93 and a fourth thermistor 94. The calculation unit 120 corrects the second resistance R2 based on the second temperature T2. The third thermistor 93 corresponds to the first temperature detection unit. The fourth thermistor 94 corresponds to the second temperature detection unit.

[0158] As a result, even if the third thermistor 93 fails, the calculation unit 120 can correct the second resistance R2 using the second temperature T2 detected by the fourth thermistor 94. Furthermore, even if the fourth thermistor 94 fails, the calculation unit 120 can correct the second resistance R2 using the second temperature T2 detected by the third thermistor 93. Therefore, the redundancy of the current detection device 20 is improved.

[0159] (Second Embodiment) In the second embodiment, as shown in Figures 10 to 12, the current detection device 20 includes a circuit board 40 and a connector housing 110 instead of the first circuit board 41, the second circuit board 42, the first connector housing 111, and the second connector housing 112. Also, the arrangement of the first connection part 51, the second connection part 52, the third connection part 53, and the fourth connection part 54 differs from that of the first embodiment. Furthermore, the arrangement of the first terminal part 61, the second terminal part 62, the third terminal part 63, and the fourth terminal part 64 differs from that of the first embodiment. Also, the arrangement of the first wiring 71, the second wiring 72, the third wiring 73, and the fourth wiring 74 differs from that of the first embodiment. Furthermore, the arrangement of the first thermistor 91, the second thermistor 92, the third thermistor 93, and the fourth thermistor 94 differs from that of the first embodiment. Other than these, it is the same as the first embodiment.

[0160] The substrate 40 is a printed circuit board. The substrate 40 also has a substrate surface 401, a substrate back surface 402, a first through-hole 413, a second through-hole 414, a third through-hole 423, and a fourth through-hole 424.

[0161] The substrate surface 401 is the surface of the substrate 40 that is perpendicular to the thickness direction DT and corresponds to the surface of the substrate 40 that intersects with the thickness direction DT. Furthermore, the substrate surface 401 is located on the opposite side of the substrate 40 from the first resistor 31 and the second resistor 32.

[0162] The back surface 402 of the substrate is the surface of the substrate 40 that is perpendicular to the thickness direction DT and corresponds to the surface of the substrate 40 that intersects with the thickness direction DT. Furthermore, the back surface 402 of the substrate is located on the side of the substrate 40 that contains the first resistor 31 and the second resistor 32, that is, it is located on the opposite side of the substrate 40 from the substrate surface 401.

[0163] The first through-hole 413, the second through-hole 414, the third through-hole 423, and the fourth through-hole 424 are holes that penetrate the substrate surface 401 and the substrate back surface 402, respectively.

[0164] Furthermore, as shown in Figures 11 and 12, the first connection part 51, the second connection part 52, the third connection part 53, and the fourth connection part 54 are located on the back surface 402 of the substrate. In addition, the first terminal part 61, the second terminal part 62, the third terminal part 63, and the fourth terminal part 64 are located in the first through-hole 413, the second through-hole 414, the third through-hole 423, and the fourth through-hole 424 of the substrate 40, respectively. Also, as shown in Figure 10, the first wiring 71, the second wiring 72, the third wiring 73, and the fourth wiring 74 are located on the surface 401 of the substrate. Furthermore, the first thermistor 91, the second thermistor 92, the third thermistor 93, and the fourth thermistor 94 are located on the surface 401 of the substrate.

[0165] The connector housing 110 is formed in a cylindrical shape from, for example, resin. The connector housing 110 is also placed on the substrate 40. Furthermore, the connector housing 110 houses the first pin 81, the second pin 82, the third pin 83, the fourth pin 84, two first thermistor pins 101, two second thermistor pins 102, two third thermistor pins 103, and two fourth thermistor pins 104. When the connector housing 110 is projected in the thickness direction DT, the projected connector housing 110 is separated from the first resistor section 31, the second resistor section 32, the first connection section 51, the second connection section 52, the third connection section 53, and the fourth connection section 54 without overlapping. Furthermore, the connector housing 110 projected in the thickness direction DT overlaps with the second busbar section 22, the intermediate section 25, and the third busbar section 23.

[0166] As described above, the current detection device 20 of the second embodiment is configured as described. This second embodiment also provides the same effects as the first embodiment. Furthermore, the second embodiment also provides the effects described below.

[0167] [2-1] The current detection device 20 includes a circuit board 40. The circuit board 40 has a first terminal section 61, a second terminal section 62, a third terminal section 63, and a fourth terminal section 64.

[0168] As a result, the number of circuit boards 40 is reduced compared to the case where the first terminal section 61, second terminal section 62, third terminal section 63, and fourth terminal section 64 are arranged on two or more circuit boards 40. Therefore, the number of components in the current detection device 20 is reduced, and thus the cost of the current detection device 20 is reduced.

[0169] [2-2] The current detection device 20 comprises a first pin 81, a second pin 82, a third pin 83, a fourth pin 84, and a connector housing 110. The connector housing 110 houses the first pin 81, the second pin 82, the third pin 83, and the fourth pin 84.

[0170] This reduces the number of connector housings 110 compared to the case where the first pin 81, second pin 82, third pin 83, and fourth pin 84 are housed in two or more connector housings 110. As a result, the number of components in the current detection device 20 is reduced, and therefore the cost of the current detection device 20 is reduced.

[0171] [2-3] Here, heat from the first resistor 31 and the second resistor 32 is transferred to the connector housing 110, which may cause damage to the connector housing 110.

[0172] Therefore, when the connector housing 110 is projected in the thickness direction DT, the projected connector housing 110 is separated from the first resistor 31 and the second resistor 32 without overlapping.

[0173] As a result, the connector housing 110, when projected in the thickness direction DT, is separated from the first and second resistors 31 and 32, compared to the case where the connector housing 110 overlaps with the first and second resistors 31 and 32. Therefore, heat from the first and second resistors 31 and 32 is less likely to be transferred to the connector housing 110. Consequently, damage to the connector housing 110 is suppressed.

[0174] (Third embodiment) In the third embodiment, as shown in Figure 13, the shapes of the first recess 212, the first rectifier 213, the second recess 222, the second rectifier 223, the third recess 232, the third rectifier 233, the fourth recess 242, and the fourth rectifier 243 differ from those of the first embodiment. Otherwise, it is the same as the first embodiment.

[0175] Instead of the first recess 212 being recessed in the width direction DW from both sides of the first side surface 211, it is recessed in the width direction DW from one side of the first side surface 211. As a result, the second end 2132 of the first rectifier section 213 is located on the first side surface 211 opposite to the first recess 212.

[0176] Instead of the second recess 222 being recessed in the width direction DW from both sides of the second side surface 221, it is recessed in the width direction DW from one side of the second side surface 221. Therefore, the fourth end 2232 of the second rectifier section 223 is located on the second side surface 221 opposite to the second recess 222.

[0177] Instead of the third recess 232 being recessed in the width direction DW from both sides of the third side surface 231, it is recessed in the width direction DW from one side of the third side surface 231. As a result, the sixth end 2332 of the third rectifier 233 is located on the third side surface 231 opposite to the third recess 232.

[0178] Instead of the fourth recess 242 being recessed in the width direction DW from both sides of the fourth side surface 241, it is recessed in the width direction DW from one side of the fourth side surface 241. Therefore, the eighth end 2432 of the fourth rectifier section 243 is located on the fourth side surface 241 opposite to the fourth recess 242.

[0179] As described above, the current detection device 20 of the third embodiment is configured as described above. This third embodiment also provides the same effects as the first embodiment.

[0180] (Fourth Embodiment) In the fourth embodiment, as shown in Figure 14, the shapes of the first recess 212, the second recess 222, the third recess 232, and the fourth recess 242 differ from those of the first embodiment. Otherwise, it is the same as the first embodiment.

[0181] Instead of penetrating in the thickness direction DT, the first recess 212 does not penetrate in the thickness direction DT and includes the first recess surface 2120. The first recess surface 2120 is perpendicular to the thickness direction DT and is a surface facing the thickness direction DT.

[0182] Instead of penetrating in the thickness direction DT, the second recess 222 does not penetrate in the thickness direction DT and includes a second recess surface 2220. The second recess surface 2220 is perpendicular to the thickness direction DT and is a surface facing the thickness direction DT.

[0183] Instead of penetrating in the thickness direction DT, the third recess 232 does not penetrate in the thickness direction DT and includes the third recess surface 2320. The third recess surface 2320 is perpendicular to the thickness direction DT and is a surface facing the thickness direction DT.

[0184] Instead of penetrating in the thickness direction DT, the fourth recess 242 does not penetrate in the thickness direction DT and includes the fourth recess surface 2420. The fourth recess surface 2420 is perpendicular to the thickness direction DT and is a surface facing the thickness direction DT.

[0185] As described above, the current detection device 20 of the fourth embodiment is configured as described. This fourth embodiment also provides the same effects as the first embodiment.

[0186] (Fifth embodiment) In the fifth embodiment, as shown in Figure 15, the first busbar portion 21 further has a first plate surface 215. The first busbar portion 21 also has a first hole 216 instead of a first recess 212. The second busbar portion 22 further has a second plate surface 225. The second busbar portion 22 also has a second hole 226 instead of a second recess 222. The third busbar portion 23 further has a third plate surface 235. The third busbar portion 23 also has a third hole 236 instead of a third recess 232. The fourth busbar portion 24 further has a fourth plate surface 245. The fourth busbar portion 24 also has a fourth hole 246 instead of a fourth recess 242. Furthermore, the configurations of the first rectifier 213, second rectifier 223, third rectifier 233, and fourth rectifier 243 differ from those of the first embodiment. Other than these differences, it is the same as the first embodiment.

[0187] The first plate surface 215 is a surface of the first busbar portion 21 that is perpendicular to the thickness direction DT and corresponds to a surface of the first busbar portion 21 that intersects with the thickness direction DT.

[0188] Two first holes 216 are formed and are aligned in the width direction DW. The first holes 216 extend from the interior of the first plate surface 215. Furthermore, the first holes 216 penetrate both sides of the first plate surface 215. The first holes 216 are not in contact with the first resistor 31 and are separated from the first resistor 31. Note that the number of first holes 216 is two, but is not limited to this. There should be at least one first hole 216. Also, the shape of the first holes 216 is a rectangular prism, but is not limited to this. The shape of the first holes 216 may be a polygonal prism, a cylinder, or the like.

[0189] The first rectifier section 213 is adjacent to the center side of the first busbar section 21 in the width direction DW of the first hole 216 and also adjacent to the width direction DW. Furthermore, the first rectifier section 213 extends in the width direction DW. In addition, the first end 2131 is the boundary between the first rectifier section 213 and the first hole 216. The second end 2132 is the end of the first rectifier section 213 opposite to the first end 2131, and here it is the boundary between the first rectifier section 213 and the other first hole 216.

[0190] The second plate surface 225 is a surface of the second busbar portion 22 that is perpendicular to the thickness direction DT and corresponds to a surface of the second busbar portion 22 that intersects with the thickness direction DT.

[0191] Two second holes 226 are formed and are aligned in the width direction DW. The second holes 226 extend from the interior of the second plate surface 225. Furthermore, the second holes 226 penetrate both sides of the second plate surface 225. The second holes 226 are not in contact with the first resistor 31 and are separated from the first resistor 31. Note that the number of second holes 226 is two, but is not limited to this. There should be at least one second hole 226. Also, the shape of the second holes 226 is a rectangular prism, but is not limited to this. The shape of the second holes 226 may be a polygonal prism, a cylinder, or the like.

[0192] The second rectifier section 223 is adjacent to the center side of the second busbar section 22 in the width direction DW of the second hole 226 and also adjacent to the width direction DW. The second rectifier section 223 extends in the width direction DW. Furthermore, the third end 2231 is the boundary between the second rectifier section 223 and the second hole 226. The fourth end 2232 is the end of the second rectifier section 223 opposite to the third end 2231, and here it is the boundary between the second rectifier section 223 and the other second hole 226.

[0193] The third plate surface 235 is the surface of the third busbar portion 23 that is perpendicular to the thickness direction DT and corresponds to the surface of the third busbar portion 23 that intersects with the thickness direction DT.

[0194] Two third holes 236 are formed and are aligned in the width direction DW. The third holes 236 extend from the interior of the third plate surface 235. Furthermore, the third holes 236 penetrate both sides of the third plate surface 235. The third holes 236 are not in contact with the second resistor 32 and are separated from it. Note that, while there are two third holes 236 here, the number is not limited to this. At least one third hole 236 is sufficient. Also, while the shape of the third holes 236 is a rectangular prism, the shape is not limited to this. The shape of the third holes 236 may be a polygonal prism, a cylinder, or the like.

[0195] The third rectifier section 233 is adjacent to the center side of the third busbar section 23 in the width direction DW of the third hole 236 and also in the width direction DW. The third rectifier section 233 extends in the width direction DW. Furthermore, the fifth end 2331 is the boundary between the third rectifier section 233 and the third hole 236. The sixth end 2332 is the end of the third rectifier section 233 opposite to the fifth end 2331, and here it is the boundary between the third rectifier section 233 and the other third hole 236.

[0196] The fourth plate surface 245 is the surface of the fourth busbar portion 24 that is perpendicular to the thickness direction DT and corresponds to the surface of the fourth busbar portion 24 that intersects with the thickness direction DT.

[0197] Two fourth holes 246 are formed and are aligned in the width direction DW. Furthermore, the fourth holes 246 extend from the interior of the fourth plate surface 245. Additionally, the fourth holes 246 penetrate both sides of the fourth plate surface 245. The fourth holes 246 are not in contact with the second resistor 32 and are separated from it. Note that, while there are two fourth holes 246 here, this is not limited to this. At least one fourth hole 246 is sufficient. Also, while the shape of the fourth holes 246 is a rectangular prism, this is not limited to this. The shape of the fourth holes 246 may be a polygonal prism, a cylinder, or the like.

[0198] The fourth rectifier section 243 is adjacent to the center side of the fourth busbar section 24 in the width direction DW of the fourth hole 246 and also in the width direction DW. Furthermore, the fourth rectifier section 243 extends in the width direction DW. In addition, the seventh end 2431 is the boundary between the fourth rectifier section 243 and the fourth hole 246. The eighth end 2432 is the end of the fourth rectifier section 243 opposite to the seventh end 2431, and here it is the boundary between the fourth rectifier section 243 and the other fourth hole 246.

[0199] As described above, the current detection device 20 of the fifth embodiment is configured as described above. This fifth embodiment also provides the same effects as the first embodiment.

[0200] (Sixth Embodiment) In the sixth embodiment, as shown in Figure 16, the shapes of the first hole 216, the second hole 226, the third hole 236, and the fourth hole 246 differ from those of the fifth embodiment.

[0201] Instead of the first hole 216 penetrating in the thickness direction DT, it is formed as a closed hole and does not penetrate in the thickness direction DT. As a result, the first hole 216 includes the first bottom surface 2160. The first bottom surface 2160 is perpendicular to the thickness direction DT and is a surface facing the thickness direction DT.

[0202] Instead of the second hole 226 penetrating in the thickness direction DT, it is formed as a bottomed hole and does not penetrate in the thickness direction DT. As a result, the second hole 226 includes the second bottom surface 2260. The second bottom surface 2260 is perpendicular to the thickness direction DT and is a surface facing the thickness direction DT.

[0203] Instead of the third hole 236 penetrating in the thickness direction DT, it is formed as a bottomed hole and does not penetrate in the thickness direction DT. As a result, the third hole 236 includes the third bottom surface 2360. The third bottom surface 2360 is perpendicular to the thickness direction DT and is a surface facing the thickness direction DT.

[0204] Instead of penetrating in the thickness direction DT, the fourth hole 246 is formed as a closed hole and does not penetrate in the thickness direction DT. As a result, the fourth hole 246 includes the fourth bottom surface 2460. The fourth bottom surface 2460 is perpendicular to the thickness direction DT and is a surface facing the thickness direction DT.

[0205] As described above, the current detection device 20 of the sixth embodiment is configured as described above. This sixth embodiment also provides the same effects as the fifth embodiment.

[0206] (Seventh Embodiment) In the seventh embodiment, as shown in Figures 17 and 18, the current detection device 20 does not have a first connection part 51, a second connection part 52, a third connection part 53, and a fourth connection part 54. Also, the configuration of the first terminal part 61, the second terminal part 62, the third terminal part 63, the fourth terminal part 64, the first voltage detection point P1, the second voltage detection point P2, the third voltage detection point P3, and the fourth voltage detection point P4 differs from that of the first embodiment. Other than these, it is the same as the first embodiment.

[0207] Instead of being connected to the first resistor 31 side of the first busbar 21 via the first connection part 51, the first terminal 61 is directly connected to the first resistor 31 side of the first busbar 21. Therefore, the first terminal 61 is connected to the first busbar 21 side of the first resistor 31 via the first busbar 21 without going through the first connection part 51. As a result, the first terminal 61 outputs a signal corresponding to the first voltage V1. In this case, the first voltage detection point P1 is the contact point between the first terminal 61 and the first busbar 21.

[0208] Instead of being connected to the first resistor 31 side of the second busbar 22 via the second connection part 52, the second terminal 62 is directly connected to the first resistor 31 side of the second busbar 22. Therefore, the second terminal 62 is connected to the second busbar 22 side of the first resistor 31 via the second busbar 22 without going through the second connection part 52. As a result, the second terminal 62 outputs a signal corresponding to the second voltage V2. Furthermore, in this case, the second voltage detection point P2 is the contact point between the second terminal 62 and the second busbar 22.

[0209] Instead of being connected to the second resistor 32 side of the third busbar 23 via the third connection 53, the third terminal 63 is directly connected to the second resistor 32 side of the third busbar 23. Therefore, the third terminal 63 is connected to the third busbar 23 side of the second resistor 32 via the third busbar 23 without going through the third connection 53. As a result, the third terminal 63 outputs a signal corresponding to the third voltage V3. In this case, the third voltage detection point P3 is the contact point between the third terminal 63 and the third busbar 23.

[0210] Instead of being connected to the second resistor 32 side of the fourth busbar 24 via the fourth connector 54, the fourth terminal 64 is directly connected to the second resistor 32 side of the fourth busbar 24. Therefore, the fourth terminal 64 is connected to the fourth busbar 24 side of the second resistor 32 via the fourth busbar 24 without going through the fourth connector 54. As a result, the fourth terminal 64 outputs a signal corresponding to the fourth voltage V4. Furthermore, in this case, the fourth voltage detection point P4 is the contact point between the fourth terminal 64 and the fourth busbar 24.

[0211] As described above, the current detection device 20 of the seventh embodiment is configured as described above. This seventh embodiment also provides the same effects as the first embodiment.

[0212] (Eighth embodiment) In the eighth embodiment, as shown in Figures 19 and 20, the configurations of the first busbar section 21, the second busbar section 22, the third busbar section 23, and the fourth busbar section 24 differ from those of the seventh embodiment. Also, the configurations of the first terminal section 61, the second terminal section 62, the third terminal section 63, and the fourth terminal section 64 differ from those of the seventh embodiment. Other than these differences, it is the same as the seventh embodiment.

[0213] The first busbar section 21 further includes a first busbar section hole 217. The first busbar section hole 217 is formed in the portion of the first busbar section 21 that is on the side of the first resistor section 31 and penetrates through in the thickness direction DT. The first busbar section hole 217 is also in communication with the first through-hole 413.

[0214] The first terminal portion 61 is formed in a screw shape. Furthermore, the first terminal portion 61 and the first busbar portion 21 are connected by a portion of the first terminal portion 61 being inserted into the first through-hole 413 and the first busbar portion hole 217.

[0215] The second busbar section 22 further has a second busbar section hole 227. The second busbar section hole 227 is formed in the portion of the second busbar section 22 that is on the side of the first resistor section 31 and penetrates through in the thickness direction DT. The second busbar section hole 227 is also in communication with the second through-hole 414.

[0216] The second terminal portion 62 is formed in a screw shape. Furthermore, the second terminal portion 62 and the second busbar portion 22 are connected by a portion of the second terminal portion 62 being inserted into the second through-hole 414 and the second busbar portion hole 227.

[0217] The third busbar section 23 further has a third busbar section hole 237. The third busbar section hole 237 is formed in the portion of the third busbar section 23 that is on the side of the second resistor section 32 and penetrates through in the thickness direction DT. The third busbar section hole 237 is also in communication with the third through-hole 423.

[0218] The third terminal portion 63 is formed in a screw shape. Furthermore, a portion of the third terminal portion 63 is inserted into the third through-hole 423 and the third busbar portion hole 237, thereby connecting the third terminal portion 63 and the third busbar portion 23.

[0219] The fourth busbar section 24 further has a fourth busbar section hole 247. The fourth busbar section hole 247 is formed in the portion of the fourth busbar section 24 that is on the side of the second resistor section 32 and penetrates in the thickness direction DT. The fourth busbar section hole 247 is also in communication with the fourth through-hole 424.

[0220] The fourth terminal portion 64 is formed in a screw shape. Furthermore, a portion of the fourth terminal portion 64 is inserted into the fourth through-hole 424 and the fourth busbar portion hole 247, thereby connecting the fourth terminal portion 64 and the fourth busbar portion 24.

[0221] As described above, the current detection device 20 of the eighth embodiment is configured as described above. This eighth embodiment also provides the same effects as the seventh embodiment.

[0222] (Ninth Embodiment) In the ninth embodiment, the current detection device 20 does not include the intermediate section 25, the third busbar section 23, the fourth busbar section 24, and the second substrate 42, as shown in Figure 21. Furthermore, the current detection device 20 does not include the third connection section 53, the fourth connection section 54, the third terminal section 63, the fourth terminal section 64, the third voltage detection point P3, the fourth voltage detection point P4, the third wiring 73, and the fourth wiring 74. In addition, the current detection device 20 does not include the third pin 83, the fourth pin 84, the third thermistor 93, the fourth thermistor 94, the pin for the third thermistor 103, the pin for the fourth thermistor 104, and the second connector housing 112. Moreover, the second busbar section 22 has a second connection hole 240 in addition to the second side surface 221, the second recess 222, and the second rectifier section 223. Furthermore, bolts (not shown) are inserted into the second connection hole 240 of the second busbar section 22 and a hole provided in the inverter 14. This connects the second busbar section 22 to the inverter 14. Therefore, the battery 12, the first busbar section 21, the first resistor section 31, the second busbar section 22, and the inverter 14 are connected in series. Other than these, the configuration is the same as in the first embodiment. Even with this configuration, current detection can be easily performed, and a decrease in current detection accuracy is suppressed, similar to the first embodiment.

[0223] (Other embodiments) This disclosure is not limited to the embodiments described above, and modifications can be made to these embodiments as appropriate. Furthermore, it goes without saying that, in each of the embodiments described above, the elements constituting the embodiment are not necessarily essential, except in cases where they are explicitly stated to be particularly essential or where they are clearly considered essential in principle.

[0224] The calculation unit and method described in this disclosure may be implemented by a dedicated computer provided by configuring a processor and memory programmed to perform one or more functions embodied by a computer program. Alternatively, the calculation unit and method described in this disclosure may be implemented by a dedicated computer provided by configuring a processor by one or more dedicated hardware logic circuits. Alternatively, the calculation unit and method described in this disclosure may be implemented by one or more dedicated computers configured by a combination of a processor and memory programmed to perform one or more functions and a processor configured by one or more hardware logic circuits. Furthermore, the computer program may be stored as instructions executed by the computer on a computer-readable non-transitional tangible recording medium.

[0225] In each of the embodiments described above, the current detected and calculated by the current detection device 20 is the current flowing from the battery 12 to the inverter 14. However, the current detected and calculated by the current detection device 20 is not limited to the current flowing from the battery 12 to the inverter 14. The current detected and calculated by the current detection device 20 may be, for example, the current flowing from the inverter 14 to the motor generator 16.

[0226] The above embodiments may be combined as appropriate.

[0227] (Disclosure of the present invention) [Claim 1] A current detection device, A first busbar section (21) formed in the shape of a plate, A resistor (31) is connected to the first busbar section and has an electrical resistance greater than the electrical resistance of the first busbar section, A second busbar section (22) is connected to the side of the resistor section opposite to the first busbar section, and has an electrical resistance smaller than that of the resistor section. The first terminal section (61) outputs a signal corresponding to the first voltage (V1), which is the voltage applied to the first busbar section side of the resistor section, The second terminal (62) outputs a signal corresponding to the second voltage (V2), which is the voltage applied to the second busbar side of the resistor, A substrate (40, 41) on which the first terminal portion and the second terminal portion are arranged, The substrate, the resistor side of the first busbar section, and the first terminal section are connected to the first connection section (51), The substrate, the resistor side of the second busbar section, and the second terminal section are connected to the second connection section (52), The first detection point (P1) is the contact point between the first terminal portion and the first connection portion, The second detection point (P2), which is the contact point between the second terminal portion and the second connection portion, A calculation unit (120) calculates the device current (Ib), which is the current flowing from the external device (12) to the second busbar via the first busbar and the resistor, based on the first voltage and the second voltage and the electrical resistance of the resistor, Equipped with, The first busbar section is, The side surface (211) intersecting the width direction (DW) of the first busbar section, A recess (212) that extends inward from the aforementioned side surface in the width direction, The rectifier section (213) extends in the width direction adjacent to the recess in the width direction and through which current from the external device flows, It has, The rectifier section is, The first end (2131), which is the boundary with the recess, The second end (2132), which is the end opposite to the first end, Includes, If we define the surface passing through the first end and perpendicular to the width direction as the first surface (S1), and the surface passing through the second end and perpendicular to the width direction as the second surface (S2), The first detection point and the second detection point are current detection devices arranged in the width direction within the range from the first surface to the second surface. [Claim 2] The current detection device according to claim 1, wherein the recess is not in contact with the resistive portion and is located away from the resistive portion. [Claim 3] The current detection device according to claim 1 or 2, wherein the recess penetrates in the thickness direction (DT) of the first busbar portion. [Claim 4] The current detection device according to claim 1 or 2, wherein the recess includes a recessed surface (2120) facing the thickness direction (DT) of the first busbar portion. [Claim 5] The aforementioned side is the first side, The recess is a first recess, The rectifier is a first rectifier, The aforementioned second bass section is, A second side surface (221) intersecting the width direction, A second recess (222) that is recessed in the width direction from the second side surface, A second rectifier section (223) extends in the width direction adjacent to the second recess in the width direction, and through which current flows from the external device via the first busbar section and the resistor section, It has, The second rectifier section is, The third end (2231), which is the boundary with the second recess, The fourth end (2232), which is the end opposite to the aforementioned third end, Includes, If we define the third surface (S3) as the plane passing through the third end and perpendicular to the width direction, and the fourth surface (S4) as the plane passing through the fourth end and perpendicular to the width direction, The current detection device according to any one of claims 1 to 4, wherein the first detection point and the second detection point are arranged in the width direction within the range from the third surface to the fourth surface. [Claim 6] The aforementioned resistor is a first resistor, An intermediate section (25) is connected to the second busbar section and has an electrical resistance smaller than that of the first resistance section, The intermediate portion is connected to the side opposite to the second busbar portion, and the third busbar portion (23) is aligned with the second busbar portion in the width direction, A second resistor (32) is connected to the third busbar and is positioned apart from the first resistor in the width direction, and has an electrical resistance greater than that of the third busbar, A fourth busbar section (24) is connected to the side of the second resistor section opposite to the third busbar section, and is positioned apart from the first busbar section in the width direction, and has an electrical resistance smaller than that of the second resistor section. A third terminal section (63) outputs a signal corresponding to the third voltage (V3), which is the voltage applied to the third busbar section side of the second resistor section, A fourth terminal section (64) outputs a signal corresponding to the fourth voltage (V4), which is the voltage applied to the fourth busbar section side of the second resistor section, Equipped with, The current detection device according to any one of claims 1 to 4, wherein the calculation unit calculates the device current based on the first voltage, the second voltage, the third voltage, and the fourth voltage, and the electrical resistance of the first resistor and the electrical resistance of the second resistor. [Claim 7] The substrate (40) has the first terminal section, the second terminal section, the third terminal section, and the fourth terminal section arranged on it. The current detection device is The substrate, the second resistor side of the third busbar section, and the third terminal section are connected to a third connection section (53), The substrate, the second resistor side of the fourth busbar section, and the fourth terminal section are connected to the fourth connection section (54), The third detection point (P3), which is the contact point between the third terminal and the third connection, The fourth detection point (P4), which is the contact point between the fourth terminal and the fourth connection, The current detection device according to claim 6, further comprising: [Claim 8] The substrate is the first substrate (41), The current detection device is The second substrate (42) on which the third terminal portion and the fourth terminal portion are arranged, The second substrate, the second resistor side of the third busbar section, and the third terminal section are connected to a third connection section (53), The second substrate, the second resistor side of the fourth busbar section, and the fourth terminal section are connected to the fourth connection section (54), The third detection point (P3), which is the contact point between the third terminal and the third connection, The fourth detection point (P4), which is the contact point between the fourth terminal and the fourth connection, The current detection device according to claim 6, further comprising: [Claim 9] The aforementioned side is the first side, The recess is a first recess, The rectifier is a first rectifier, The third bass section is, A second side surface (231) intersecting the width direction, A second recess (232) that is recessed in the width direction from the second side surface, A second rectifier section (233) extends in the width direction while being adjacent to the second recess in the width direction, and through which current flows from the external device via the first busbar section, the first resistor section, the second busbar section and the intermediate section, It has, The second rectifier section is, The third end (2331), which is the boundary with the second recess, The fourth end (2332), which is the end opposite to the aforementioned third end, Includes, If we define the plane passing through the third end and perpendicular to the width direction as the third plane (S5), and the plane passing through the fourth end and perpendicular to the width direction as the fourth plane (S6), The current detection device according to claim 7 or 8, wherein the third detection point and the fourth detection point are arranged in the width direction within the range from the third surface to the fourth surface. [Claim 10] The aforementioned side is the first side, The recess is a first recess, The rectifier is a first rectifier, The aforementioned fourth bass section is, A second side surface (241) intersecting the width direction, A second recess (242) that is recessed in the width direction from the second side surface, A second rectifier section (243) extends in the width direction while being adjacent to the second recess in the width direction, and through which current flows from the external device via the first busbar section, the first resistor section, the second busbar section, the intermediate section, the third busbar section, and the second resistor section, It has, The second rectifier section is, The third end (2431), which is the boundary with the second recess, The fourth end (2432), which is the end opposite to the third end, Includes, If we define the plane passing through the third end and perpendicular to the width direction as the third plane (S7), and the plane passing through the fourth end and perpendicular to the width direction as the fourth plane (S8), The current detection device according to claim 7 or 8, wherein the third detection point and the fourth detection point are arranged in the width direction within the range from the third surface to the fourth surface. [Claim 11] A current detection device, A first busbar section (21) formed in the shape of a plate, A resistor (31) is connected to the first busbar section and has an electrical resistance greater than the electrical resistance of the first busbar section, A second busbar section (22) is connected to the side of the resistor section opposite to the first busbar section, and has an electrical resistance smaller than that of the resistor section. The first terminal section (61) outputs a signal corresponding to the first voltage (V1), which is the voltage applied to the first busbar section side of the resistor section, The second terminal (62) outputs a signal corresponding to the second voltage (V2), which is the voltage applied to the second busbar side of the resistor, A substrate (40, 41) on which the first terminal portion and the second terminal portion are arranged, The substrate, the resistor side of the first busbar section, and the first terminal section are connected to the first connection section (51), The substrate, the resistor side of the second busbar section, and the second terminal section are connected to the second connection section (52), The first detection point (P1) is the contact point between the first terminal portion and the first connection portion, The second detection point (P2), which is the contact point between the second terminal portion and the second connection portion, A calculation unit (120) calculates the device current (Ib), which is the current flowing from the external device (12) to the second busbar via the first busbar and the resistor, based on the first voltage and the second voltage and the electrical resistance of the resistor, Equipped with, The first busbar section is, The plate surface (215) intersecting the thickness direction (DT) of the first busbar portion, A hole (216) extending in the thickness direction from the inside of the plate surface, The rectifier section (213) is adjacent to the hole and the first busbar section in the width direction (DW) and extends in the width direction (DW), and through which current from the external device flows, It has, The rectifier section is, The first end (2131), which is the boundary with the aforementioned hole, The second end (2132), which is the end opposite to the first end, Includes, If we define the surface passing through the first end and perpendicular to the width direction as the first surface (S1), and the surface passing through the second end and perpendicular to the width direction as the second surface (S2), The first detection point and the second detection point are current detection devices arranged in the width direction within the range from the first surface to the second surface. [Claim 12] A current detection device, A first busbar section (21) formed in the shape of a plate, A resistor (31) is connected to the first busbar section and has an electrical resistance greater than the electrical resistance of the first busbar section, a second bus bar part (22) connected to a side of said resistor part opposite said first bus bar part, and having an electrical resistance smaller than the electrical resistance of said resistor part; a first terminal part (61) connected to said first bus bar part, and outputting a signal corresponding to a first voltage (V1) that is a voltage applied to the first bus bar part side of said resistor part; a second terminal part (62) connected to said second bus bar part, and outputting a signal corresponding to a second voltage (V2) that is a voltage applied to the second bus bar part side of said resistor part; a first detection point (P1) that is a contact point between said first terminal part and said first bus bar part; a second detection point (P2) that is a contact point between said second terminal part and said second bus bar part; a calculation part (120) that calculates a device current (Ib), which is a current flowing from an external device (12) to said second bus bar part via said first bus bar part and said resistor part, based on said first voltage, said second voltage, and the electrical resistance of said resistor part; comprising: said first bus bar part has: a side surface (211) intersecting the width direction (DW) of said first bus bar part; a recess (212) recessed in said width direction from said side surface; a rectifying part (213) that is adjacent to said recess in said width direction, extends in said width direction, and allows the current from said external device to flow therethrough; wherein: said rectifying part includes: a first end (2131) that is a boundary with said recess; a second end (2132) that is an end opposite to said first end, when a plane passing through said first end and orthogonal to said width direction is defined as a first plane (S1), and a plane passing through said second end and orthogonal to said width direction is defined as a second plane (S2), said first detection point and said second detection point are arranged in a range from said first plane to said second plane in said width direction, which is a current detection device. Description of Reference Numerals

[0228] 21st Bass Club 22nd Basketball Club 23. 3rd Bass Club 24 4th Basketball Club 31 1st resistance section 32 2nd resistance section 61 1st terminal section 62 2nd terminal section 63 3rd terminal section 64 4th terminal section 120 Calculation Unit

Claims

1. A current detection device, A first busbar portion (21) formed in the shape of a plate, A resistor (31) is connected to the first busbar section and has an electrical resistance greater than the electrical resistance of the first busbar section, A second busbar section (22) is connected to the side of the resistor section opposite to the first busbar section, and has an electrical resistance smaller than that of the resistor section. A first terminal section (61) outputs a signal corresponding to a first voltage (V1), which is the voltage applied to the first busbar section side of the resistor section, A second terminal (62) outputs a signal corresponding to the second voltage (V2), which is the voltage applied to the second busbar side of the resistor, A substrate (40, 41) on which the first terminal portion and the second terminal portion are arranged, The substrate, the resistor side of the first busbar section, and the first terminal section are connected to the first connection section (51), The substrate, the resistor side of the second busbar section, and the second terminal section are connected to the second connection section (52), The first detection point (P1) is the contact point between the first terminal portion and the first connection portion, The second detection point (P2) is the contact point between the second terminal portion and the second connection portion, A calculation unit (120) calculates the device current (Ib), which is the current flowing from the external device (12) to the second busbar via the first busbar and the resistor, based on the first voltage and the second voltage and the electrical resistance of the resistor, Equipped with, The first bass section is, The side surface (211) intersecting the width direction (DW) of the first busbar portion, A recess (212) that extends inward from the side in the width direction, The rectifier section (213) extends in the width direction adjacent to the recess in the width direction and through which current from the external device flows, It has, The rectifier section is, The first end (2131), which is the boundary with the recess, The second end (2132), which is the end opposite to the first end, Includes, If we define the surface passing through the first end and perpendicular to the width direction as the first surface (S1), and the surface passing through the second end and perpendicular to the width direction as the second surface (S2), The first detection point and the second detection point are current detection devices arranged in the width direction within the range from the first surface to the second surface.

2. The current detection device according to claim 1, wherein the recess is not in contact with the resistive portion and is located away from the resistive portion.

3. The current detection device according to claim 1 or 2, wherein the recess penetrates in the thickness direction (DT) of the first busbar portion.

4. The current detection device according to claim 1 or 2, wherein the recess includes a recessed surface (2120) facing the thickness direction (DT) of the first busbar portion.

5. The aforementioned side is the first side, The recess is a first recess, The rectifier section is a first rectifier section, The aforementioned second bass section is, A second side surface (221) intersecting the width direction, A second recess (222) that is recessed in the width direction from the second side surface, A second rectifier (223) extends in the width direction adjacent to the second recess in the width direction, and through which current flows from the external device via the first busbar and the resistor, It has, The second rectifier section is, The third end (2231), which is the boundary with the second recess, The fourth end (2232), which is the end opposite to the third end, Includes, If the surface passing through the third end and perpendicular to the width direction is designated as the third surface (S3), and the surface passing through the fourth end and perpendicular to the width direction is designated as the fourth surface (S4), The current detection device according to claim 1 or 2, wherein the first detection point and the second detection point are arranged in the width direction within the range from the third surface to the fourth surface.

6. The aforementioned resistor is a first resistor, An intermediate section (25) is connected to the second busbar section and has an electrical resistance smaller than that of the first resistance section, The intermediate portion is connected to the side opposite to the second busbar portion, and the third busbar portion (23) is aligned with the second busbar portion in the width direction, A second resistor (32) is connected to the third busbar section and is positioned apart from the first resistor in the width direction, and has an electrical resistance greater than that of the third busbar section. A fourth busbar section (24) is connected to the side of the second resistor section opposite to the third busbar section, and is positioned apart from the first busbar section in the width direction, and has an electrical resistance smaller than that of the second resistor section. A third terminal section (63) outputs a signal corresponding to the third voltage (V3), which is the voltage applied to the third busbar section side of the second resistor section, A fourth terminal (64) outputs a signal corresponding to the fourth voltage (V4), which is the voltage applied to the fourth busbar side of the second resistor, Equipped with, The current detection device according to claim 1, wherein the calculation unit calculates the device current based on the first voltage, the second voltage, the third voltage, and the fourth voltage, and the electrical resistance of the first resistor and the electrical resistance of the second resistor.

7. The substrate (40) has the first terminal section, the second terminal section, the third terminal section, and the fourth terminal section arranged on it. The current detection device is The substrate, the third busbar portion on the second resistor side, and the third terminal portion are connected to the third connection portion (53), The substrate, the second resistor side of the fourth busbar section, and the fourth terminal section are connected to the fourth connection section (54), The third detection point (P3) is the contact point between the third terminal portion and the third connection portion, The fourth detection point (P4), which is the contact point between the fourth terminal portion and the fourth connection portion, The current detection device according to claim 6, further comprising:

8. The substrate is a first substrate (41), The current detection device is The second substrate (42) on which the third terminal portion and the fourth terminal portion are arranged, The second substrate, the second resistor side of the third busbar section, and the third terminal section are connected to the third connection section (53), The second substrate, the second resistor side of the fourth busbar section, and the fourth terminal section are connected to the fourth connection section (54), The third detection point (P3) is the contact point between the third terminal portion and the third connection portion, The fourth detection point (P4), which is the contact point between the fourth terminal portion and the fourth connection portion, The current detection device according to claim 6, further comprising:

9. The aforementioned side is the first side, The recess is a first recess, The rectifier section is a first rectifier section, The aforementioned third bass section is, A second side surface (231) intersecting the width direction, A second recess (232) that is recessed in the width direction from the second side surface, A second rectifier section (233) extends in the width direction adjacent to the second recess in the width direction, and through which current flows from the external device via the first busbar section, the first resistor section, the second busbar section, and the intermediate section, It has, The second rectifier section is, The third end (2331), which is the boundary with the second recess, The fourth end (2332), which is the end opposite to the third end, Includes, If the surface passing through the third end and perpendicular to the width direction is designated as the third surface (S5), and the surface passing through the fourth end and perpendicular to the width direction is designated as the fourth surface (S6), The current detection device according to claim 7 or 8, wherein the third detection point and the fourth detection point are arranged in the width direction within the range from the third surface to the fourth surface.

10. The aforementioned side is the first side, The recess is a first recess, The rectifier section is a first rectifier section, The fourth busbar section is, A second side surface (241) intersecting the width direction, A second recess (242) that is recessed in the width direction from the second side surface, A second rectifier (243) extends in the width direction adjacent to the second recess in the width direction, and through which current flows from the external device via the first busbar section, the first resistor section, the second busbar section, the intermediate section, the third busbar section, and the second resistor section, It has, The second rectifier section is, The third end (2431), which is the boundary with the second recess, The fourth end (2432), which is the end opposite to the third end, Includes, If the surface passing through the third end and perpendicular to the width direction is designated as the third surface (S7), and the surface passing through the fourth end and perpendicular to the width direction is designated as the fourth surface (S8), The current detection device according to claim 7 or 8, wherein the third detection point and the fourth detection point are arranged in the width direction within the range from the third surface to the fourth surface.

11. A current detection device, A first busbar portion (21) formed in the shape of a plate, A resistor (31) is connected to the first busbar section and has an electrical resistance greater than the electrical resistance of the first busbar section, A second busbar section (22) is connected to the side of the resistor section opposite to the first busbar section, and has an electrical resistance smaller than that of the resistor section. A first terminal section (61) outputs a signal corresponding to a first voltage (V1), which is the voltage applied to the first busbar section side of the resistor section, A second terminal (62) outputs a signal corresponding to the second voltage (V2), which is the voltage applied to the second busbar side of the resistor, A substrate (40, 41) on which the first terminal portion and the second terminal portion are arranged, The substrate, the resistor side of the first busbar section, and the first terminal section are connected to the first connection section (51), The substrate, the resistor side of the second busbar section, and the second terminal section are connected to the second connection section (52), The first detection point (P1) is the contact point between the first terminal portion and the first connection portion, The second detection point (P2) is the contact point between the second terminal portion and the second connection portion, A calculation unit (120) calculates the device current (Ib), which is the current flowing from the external device (12) to the second busbar via the first busbar and the resistor, based on the first voltage and the second voltage and the electrical resistance of the resistor, Equipped with, The first bass section is, A plate surface (215) intersecting the thickness direction (DT) of the first busbar portion, A hole (216) extending in the thickness direction from the inside of the plate surface, The rectifier section (213) is adjacent to the hole and the first busbar section in the width direction (DW) and extends in the width direction (DW), and through which current from the external device flows, It has, The rectifier section is, The first end (2131), which is the boundary with the aforementioned hole, The second end (2132), which is the end opposite to the first end, Includes, If we define the surface passing through the first end and perpendicular to the width direction as the first surface (S1), and the surface passing through the second end and perpendicular to the width direction as the second surface (S2), The first detection point and the second detection point are current detection devices arranged in the width direction within the range from the first surface to the second surface.

12. A current detection device, A first busbar portion (21) formed in the shape of a plate, A resistor (31) is connected to the first busbar section and has an electrical resistance greater than the electrical resistance of the first busbar section, A second busbar section (22) is connected to the side of the resistor section opposite to the first busbar section, and has an electrical resistance smaller than that of the resistor section. A first terminal (61) is connected to the first busbar section and outputs a signal corresponding to a first voltage (V1), which is the voltage applied to the first busbar section side of the resistor section. A second terminal (62) is connected to the second busbar section and outputs a signal corresponding to the second voltage (V2), which is the voltage applied to the second busbar section side of the resistor section, The first detection point (P1) is the contact point between the first terminal portion and the first busbar portion, The second detection point (P2) is the contact point between the second terminal portion and the second busbar portion, A calculation unit (120) calculates the device current (Ib), which is the current flowing from the external device (12) to the second busbar via the first busbar and the resistor, based on the first voltage and the second voltage and the electrical resistance of the resistor, Equipped with, The first bass section is, The side surface (211) intersecting the width direction (DW) of the first busbar portion, A recess (212) that extends inward from the side in the width direction, The rectifier section (213) extends in the width direction adjacent to the recess in the width direction and through which current from the external device flows, It has, The rectifier section is, The first end (2131), which is the boundary with the recess, Including a second end (2132) which is the end opposite to the first end, If we define the surface passing through the first end and perpendicular to the width direction as the first surface (S1), and the surface passing through the second end and perpendicular to the width direction as the second surface (S2), The first detection point and the second detection point are current detection devices arranged in the width direction within the range from the first surface to the second surface.

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