Current detection device

Abstract

The current detection device (30) is provided with a resistor (5) and a pair of electrodes (6, 7), the current detection device (30) is provided with a protruding part (11), the protruding part (11) is provided with a part of the resistor (5) and a part of the pair of electrodes (6, 7), the electrodes (6, 7) are provided with first wall parts (66b, 67b) forming a part of the protruding part (11) and second wall parts (66a, 67a) forming a part of the protruding part (11), and the first wall parts (66b, 67b) and the second wall parts (66a, 67a) form a part of the protruding part (11). Detection regions (66, 67) are defined by the first wall sections (66b, 67b), the second wall sections (66a, 67a), the starting end sections (66c, 67c), and the contact surfaces (6a, 7a), and the electrodes (6, 7) have voltage detection sections (20, 21) in the detection regions (66, 67), the voltage detection sections (20, 21) being disposed with a gap between the electrodes (6, 7) and the starting end sections (66c, 67c).

Description

[0001] This application is a divisional application of an application with application date of April 20, 2021, application number 202180030732.3, and invention name “Current Detection Device”. Technical Field

[0002] The present invention relates to a current detection device, and in particular to a current detection device using a shunt resistor. Background Art

[0003] Shunt resistors are widely used for current detection. Such shunt resistors have a resistor body and electrodes connected to both ends of the resistor body. Usually, the resistor body is composed of a resistance alloy such as copper-nickel alloy, copper-manganese alloy, iron-chromium alloy, nickel-chromium alloy, etc., and the electrode is composed of a highly conductive metal such as copper. The electrode is provided with a voltage detection unit, and the voltage generated at the two ends of the resistor body is detected by connecting a wire (for example, an aluminum wire) to the voltage detection unit.

[0004] Fig.33 and Fig.34 An example of a conventional shunt resistor is shown in FIG. Fig.33 and Fig.34 As shown, the shunt resistor 100 includes a plate-shaped resistor 105 made of a resistance alloy having a predetermined thickness and width, and a pair of electrodes 106 and 107 made of a highly conductive metal connected to both ends of the resistor 105. Bolt holes 108 and 109 for fixing the shunt resistor 100 with screws or the like are formed in the electrodes 106 and 107, respectively.

[0005] The shunt resistor 100 further includes voltage detection units 120 and 121 for measuring the voltage of the resistor 105. Fig.33 In the example shown, the voltage detection parts 120 and 121 are formed integrally with the electrodes 106 and 107, respectively. The voltage detection parts 120 and 121 extend from the side surfaces of the electrodes 106 and 107 in the width direction of the electrodes 106 and 107. The voltage detection parts 120 and 121 are arranged near the resistor 105.

[0006] exist Fig.34 In the example shown, the voltage detection parts 120 and 121 are pins extending perpendicularly from the surfaces of the electrodes 106 and 107 , respectively. The voltage detection parts 120 and 121 are arranged near the resistor 105 .

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Application Publication No. 2017-5204

[0010] Patent Document 2: Japanese Patent Application Publication No. 2007-329421 Summary of the invention

[0011] Problem that the invention aims to solve

[0012] In a shunt resistor, in order to detect current under the condition that the influence of temperature change is small, the characteristic of temperature coefficient of resistance (TCR) is important. It should be noted that the temperature coefficient of resistance is an index indicating the ratio of the change in resistance value caused by temperature. Therefore, an object of the present invention is to provide a current detection device using a shunt resistor that can meet the desired temperature coefficient of resistance with a simple structure.

[0013] Solutions for solving problems

[0014] In one technical solution, a current detection device is provided, which is used for current detection, wherein the current detection device comprises: a resistor; and a pair of electrodes connected to both ends of the resistor in a first direction, the current detection device has a protrusion protruding in a second direction, the protrusion has a part of the resistor and a part of the pair of electrodes, the first direction is the configuration direction of the pair of electrodes, the second direction is a direction perpendicular to the first direction, each electrode has a first wall portion along the first direction that forms a part of the protrusion and a second wall portion along the second direction that forms a part of the protrusion, in each of the electrodes, a detection area is divided by the first wall portion, the second wall portion, a boundary line between the protrusion and the main body of the electrode, i.e., a starting end portion, and at least a part of a contact surface that contacts the resistor, and each electrode has a voltage detection portion configured in the detection area with a gap between the starting end portion.

[0015] In one embodiment, the voltage detection unit is arranged on a side closer to the resistor than a center of the detection region.

[0016] In one technical solution, the detection region protrudes more than the resistor in a thickness direction of the current detection device.

[0017] In one technical solution, the length of the first wall portion is longer than the length of the second wall portion.

[0018] In one embodiment, the current detection device further includes a wiring substrate including a detection pad connected to the voltage detection unit.

[0019] In a reference example, a shunt resistor is provided, which is a plate-shaped shunt resistor for current detection, wherein the shunt resistor comprises: a resistor body; and a pair of electrodes connected to both ends of the resistor body in a first direction, the shunt resistor having: a protrusion formed on a first side surface of the shunt resistor which is a surface parallel to the first direction; and a recess formed on a second side surface of the shunt resistor which is a surface opposite to the first side surface and extending in the same direction as the protrusion, the protrusion having a portion of the resistor body and a portion of the pair of electrodes, and the recess having a side surface of the resistor body parallel to the first direction.

[0020] In a reference example, a length of the recessed portion in a second direction perpendicular to the first direction is equal to a length of the protruding portion in the second direction.

[0021] In a reference example, the protrusion includes a pair of voltage detection parts connected to both ends of the resistor in the first direction.

[0022] In a reference example, the protrusion and the recess have a rectangular shape.

[0023] In a reference example, a method for manufacturing a shunt resistor is provided, wherein the shunt resistor includes a resistor body and a pair of electrodes connected to both ends of the resistor body, wherein a longitudinal shunt resistor base material is prepared in a state in which a pair of electrodes are connected to both ends of the resistor body in a first direction, the shunt resistor base material is cut in a convex shape along the first direction to form a protrusion of the first shunt resistor having a portion of the resistor body of the first shunt resistor and a portion of the pair of electrodes of the first shunt resistor, and the shunt resistor base material is cut in a convex shape along the first direction at a distance from the protrusion to form a recess of the first shunt resistor and a protrusion of a second shunt resistor extending in the same direction as the protrusion, the protrusion of the second shunt resistor having a portion of the resistor body of the second shunt resistor and a portion of the pair of electrodes of the second shunt resistor.

[0024] In a reference example, a current detection device is provided, wherein the current detection device comprises: the above-mentioned shunt resistor; and a current detection circuit substrate having a voltage signal wiring for transmitting a voltage signal from the shunt resistor, wherein the voltage signal wiring is electrically connected to a protruding portion of the shunt resistor.

[0025] In a reference example, the current detection circuit substrate further includes a voltage terminal pad, and the voltage terminal pad is connected to the protruding portion and the voltage signal wiring.

[0026] In a reference example, the current detection device further includes an output terminal that outputs a voltage signal from the shunt resistor, and the output terminal is mounted on a recessed portion of the shunt resistor.

[0027] Effects of the Invention

[0028] By arranging the voltage detection portion at a desired position with a gap between the detection region of the electrode constituting a part of the protrusion of the current detection device and the start end portion, a desired resistance temperature coefficient can be satisfied. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a perspective view showing one embodiment of a shunt resistor.

[0030] Figure 2 yes Figure 1 A top view of a shunt resistor is shown.

[0031] Figure 3 It is an enlarged view of the protrusion and the recess.

[0032] Figure 4 It is a perspective view showing one embodiment of a current detection device including a shunt resistor.

[0033] Figure 5 This is a perspective view showing the current detection device with the case of the voltage output device removed.

[0034] Figure 6 This is a schematic diagram showing a state where a voltage detection terminal is provided in the voltage detection unit.

[0035] Figure 7 This is a graph showing the rate of change of the resistance value of the shunt resistor due to temperature change.

[0036] Figure 8 It is a plan view showing one embodiment of a shunt resistor having no recessed portion.

[0037] Fig. 9 This is a graph showing the relationship between the length of the protruding portion in the second direction and the resistance value change rate of the shunt resistor.

[0038] Fig.10 This is a graph showing the relationship between the length of the protruding portion of the shunt resistor and the resistance value change rate of the shunt resistor.

[0039] Fig.11 This is a graph showing the rate of change of the resistance value of the shunt resistor.

[0040] Fig.12 It is a perspective view showing another embodiment of the shunt resistor.

[0041] Fig.13 yes Fig.12 Magnified view of the protrusion.

[0042] Fig.14 This is a diagram showing an example of a manufacturing process of a shunt resistor.

[0043] Fig.15 It is a schematic diagram showing still another embodiment of the shunt resistor.

[0044] Fig.16 It is a schematic diagram showing still another embodiment of the shunt resistor.

[0045] Fig.17 It is a schematic diagram showing still another embodiment of the shunt resistor.

[0046] Fig.18 It is a schematic diagram showing still another embodiment of the shunt resistor.

[0047] Fig.19 It is a schematic diagram showing another embodiment of the method for manufacturing a shunt resistor.

[0048] Fig. 20 It is a schematic diagram showing another embodiment of the method for manufacturing a shunt resistor.

[0049] Fig.21 It is a perspective view showing another embodiment of the current detection device.

[0050] Fig. 22 yes Fig.21 A side view of the current sensing device shown.

[0051] Fig.23 yes Fig.21 Magnified view of the protrusion.

[0052] Fig.24 It is a schematic diagram for explaining the position of the voltage detection unit.

[0053] Fig.25 Yes means Fig.24 A graph showing the amount of change in the resistance value of the shunt resistor caused by temperature change at each detection position.

[0054] Fig.26A It is a schematic diagram showing still another embodiment of the current detection device.

[0055] Fig.26B It is a schematic diagram showing still another embodiment of the current detection device.

[0056] Fig.27A It is a schematic diagram showing still another embodiment of the current detection device.

[0057] Fig.27B It is a schematic diagram showing still another embodiment of the current detection device.

[0058] Fig.28A It is a diagram for explaining the position of the voltage detection unit.

[0059] Fig.28B It is a diagram for explaining the position of the voltage detection unit.

[0060] Fig.29 It is a schematic diagram showing an example in which a voltage detection member is connected across a step.

[0061] Fig.30 It is a schematic diagram showing another embodiment of the protrusion.

[0062] Fig.31 It is a schematic diagram showing another embodiment of the protrusion.

[0063] Fig.32 It is a schematic diagram showing still another embodiment of the current detection device.

[0064] Fig.33 It is a diagram showing an example of a conventional shunt resistor.

[0065] Fig.34 It is a diagram showing an example of a conventional shunt resistor. DETAILED DESCRIPTION

[0066] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. It should be noted that in the accompanying drawings described below, the same or equivalent components are marked with the same reference numerals and repeated descriptions are omitted. In the multiple embodiments described below, the structure of an embodiment not specifically described is the same as that of other embodiments, so its repeated description is omitted.

[0067] Figure 1 is a perspective view showing an embodiment of the shunt resistor 1. Figure 2 yes Figure 1 The top view of the shunt resistor 1 is shown. Figure 1 and Figure 2 As shown, the shunt resistor 1 includes: a resistor 5, which is made of a resistor alloy plate material and has a predetermined thickness and width; and a pair of electrodes 6, 7, which are made of a highly conductive metal and are connected to both ends (i.e., both side connection surfaces) 5a, 5b of the resistor 5 in the first direction. The electrode 6 has a contact surface 6a that contacts one end (one connection surface) 5a of the resistor 5, and the electrode 7 has a contact surface 7a that contacts the other end (the other connection surface) 5b of the resistor 5. Bolt holes 8, 9 for fixing the shunt resistor 1 with screws or the like are formed in the electrodes 6, 7, respectively.

[0068] The first direction is the length direction of the resistor 5, which is equivalent to the length direction of the shunt resistor 1. The length direction of the shunt resistor 1 is the direction in which the electrode 6, the resistor 5, and the electrode 7 are arranged in this order. The direction perpendicular to the first direction is the second direction. The second direction is the width direction of the shunt resistor 1. Figure 1 and Figure 2 As shown, the electrodes 6 and 7 have the same structure and are arranged symmetrically with respect to the resistor 5 .

[0069] The two ends 5a, 5b of the resistor 5 are connected (joined) to the electrodes 6, 7 by welding (e.g., electron beam welding, laser beam welding, or brazing). As an example of the material of the resistor 5, a low-resistance alloy material such as a Cu-Mn alloy can be cited. As an example of the material of the electrodes 6, 7, copper (Cu) can be cited.

[0070] The shunt resistor 1 has a protrusion 11 formed on the side 1a of the shunt resistor 1 and a recess 12 formed on the side 1b of the shunt resistor 1. The protrusion 11 extends outward from the side 1a, and the recess 12 extends inward (toward the center of the shunt resistor 1) from the side 1b. The protrusion 11 and the recess 12 extend in the same direction (the second direction). The protrusion 11 and the recess 12 have a rectangular shape when viewed from above (when viewed from a direction perpendicular to both the first direction and the second direction).

[0071] The side surface 1a is a surface of the shunt resistor 1 parallel to the first direction, and has the side surface 6c of the electrode 6 and the side surface 7c of the electrode 7. The side surface 1b is a surface of the shunt resistor 1 parallel to the first direction, and is a surface on the side opposite to the side surface 1a. The side surface 1b has the side surface 6b of the electrode 6 and the side surface 7b of the electrode 7. The side surfaces 6b and 7b are parallel to the side surfaces 6c and 7c.

[0072] Figure 3 1 is an enlarged view of the protrusion 11 and the recess 12. The protrusion 11 has a part of the resistor 5 and a part of the electrodes 6 and 7. Specifically, the protrusion 11 has a portion 14 that is a part of the resistor 5 and voltage detection portions 20 and 21 for measuring the voltage generated at the two ends 5a and 5b of the resistor 5. The length of the portion 14 in the second direction is represented by a length t1 (the length t1 of the protrusion 11 in the second direction), which is the distance from the side surfaces 6c and 7c of the electrodes 6 and 7 to the side surface 5c of the resistor 5.

[0073] The voltage detection parts 20 and 21 are parts of the electrodes 6 and 7, respectively. That is, the electrode 6 has the voltage detection part 20, and the electrode 7 has the voltage detection part 21. The voltage detection part 20 extends outward from the side surface 6c of the electrode 6, and the voltage detection part 21 extends outward from the side surface 7c of the electrode 7. The voltage detection parts 20 and 21 are connected to the two ends 5a and 5b of the resistor 5, respectively. The voltage detection parts 20 and 21 are arranged symmetrically with respect to the part 14. The lengths of the voltage detection parts 20 and 21 in the second direction are also represented by the length t1.

[0074] The concave portion 12 has a side surface 5d of the resistor 5 parallel to the first direction. Specifically, in the present embodiment, the concave portion 12 is parallel to the first direction (see Figure 2 ) is formed by the side 6d of the electrode 6, the side 5d of the resistor 5, and the side 7d of the electrode 7. In the present embodiment, the width W1 of the protrusion 11 (the length of the protrusion 11 in the first direction) is the same as the width W2 of the recess 12 (the length of the recess 12 in the first direction), and the length t1 of the protrusion 11 in the second direction (i.e., the width direction of the shunt resistor 1) is the same as the length t2 of the recess 12 in the second direction. The position of the protrusion 11 in the first direction is the same as the position of the recess 12 in the first direction. That is, the side 11a of the protrusion 11 is arranged on the extension line of the side 12a of the recess 12, and the side 11b of the protrusion 11 is arranged on the extension line of the side 12b of the recess 12.

[0075] Figure 4 1 is a perspective view showing an embodiment of a current detection device 30 having a shunt resistor 1. The current detection device 30 further includes a voltage output device 31 for outputting the voltage of the resistor 5 (the voltage generated at the two ends 5a, 5b of the resistor 5) to the outside. The voltage output device 31 is connected to the shunt resistor 1. The voltage output device 31 includes a non-conductive housing 32 covering the resistor 5 and an output terminal 35 (output connector 35) for outputting a voltage signal (the voltage of the resistor 5) from the shunt resistor 1. The output connector 35 includes a first terminal, a second terminal, and a ground terminal, which are not shown.

[0076] Figure 5 FIG. 2 is a perspective view showing the current detection device 30 when the housing 32 of the voltage output device 31 is removed. Figure 5 As shown, the voltage output device 31 further includes a current detection circuit substrate 34. The current detection circuit substrate 34 has voltage signal wirings 46 and 47 for transmitting the voltage signal from the shunt resistor 1 (the voltage of the resistor 5) to the output terminal 35, and a ground wiring 50. The current detection circuit substrate 34 is arranged on the shunt resistor 1, and the output terminal 35 is mounted on the recess 12.

[0077] The current detection circuit substrate 34 further includes voltage terminal pads 36 and 37 (copper foil portions 36 and 37). One end of a voltage signal wiring 46 is connected to the voltage terminal pad 36, and the other end is connected to the first terminal of the output connector 35. One end of a voltage signal wiring 47 is connected to the voltage terminal pad 37, and the other end is connected to the second terminal of the output connector 35. The voltage signal wiring 46 and 47 extend from the second direction (see FIG. 1 ) above the protrusion 11. Figure 2 ) to the first direction (refer to Figure 2 ) is bent and wired. One end of the ground wiring 50 is connected to the voltage terminal pad 36, and the other end is connected to the ground terminal of the output connector 35. The voltage signal wirings 46, 47, the ground wiring 50, and the voltage terminal pads 36, 37 are formed of a highly conductive metal (copper in this embodiment).

[0078] The voltage terminal pad 36 is connected to the voltage detection position 16 (see FIG. 1 ) of the voltage detection unit 20 of the protruding portion 11 via internal wiring (not shown) of the current detection circuit substrate 34. Figure 3 Similarly, the voltage terminal pad 37 is connected to the voltage detection position 17 (see FIG. 1 ) of the voltage detection portion 21 of the protruding portion 11 via an internal wiring not shown. Figure 3 ) connection. That is, the voltage signal wirings 46, 47 are electrically connected to the voltage detection parts 20, 21 of the protrusion 11, respectively. The above-mentioned internal wiring and the voltage detection parts 20, 21 are connected by methods such as soldering. The worker connects a cable having a connector that is embedded in the output terminal 35 and measures the voltage generated at the two ends 5a, 5b of the resistor 5. With such a structure, the voltage of the resistor 5 can be simply measured. In one embodiment, an operational amplifier (amplifier), an A / D converter and / or a temperature sensor for amplifying the voltage signal from the shunt resistor 1 can also be mounted on the current detection circuit substrate 34.

[0079] In one embodiment, if Figure 6 As shown, voltage detection terminals 38 and 39 may be provided on the voltage detection parts 20 and 21, respectively. The voltage detection terminals 38 and 39 are conductive pins extending vertically from the surfaces of the voltage detection parts 20 and 21, respectively. Specifically, the voltage detection terminals 38 and 39 are connected to the voltage detection positions 16 and 17 of the voltage detection parts 20 and 21, respectively, by soldering or the like. The voltage generated at both ends of the resistor 5 is measured by connecting a wire (for example, an aluminum wire) to the voltage detection terminals 38 and 39, respectively, or by passing the voltage detection terminals 38 and 39 through a through hole formed in the circuit substrate and conducting and connecting them to the wiring formed in the circuit substrate, etc. With such a structure, the voltage of the resistor 5 can be measured with a simple structure.

[0080] Figure 7It is a graph showing the rate of change of the resistance value of the shunt resistor 1 due to temperature change. Figure 7 The horizontal axis represents the temperature of the shunt resistor 1, Figure 7 The vertical axis represents the resistance value change rate of the shunt resistor 1. The curve represented by the solid line represents the resistance value change rate of the shunt resistor 1 of the present embodiment, and the curve represented by the dotted line represents the resistance value change rate of the conventional shunt resistor ( Fig.33 The resistance value change rate of the shunt resistor 100) shown. Figure 7 The results are shown when a copper-manganese alloy is used as the resistor 5 .

[0081] It is clear from the comparison of the variation range of the resistance value variation rate of the shunt resistor 1 of the present embodiment and the variation range of the resistance value variation rate of the conventional shunt resistor that the shunt resistor 1 of the present embodiment can reduce the variation range of the resistance value variation rate caused by temperature change. That is, Figure 7 The result shows that the temperature coefficient of resistance (TCR) of the shunt resistor 1 can be reduced. By forming the protrusion 11 including a part of the resistor 5 and a part of the electrodes 6 and 7 as described above, the equipotential lines are deformed, and as a result, the temperature coefficient of resistance of the shunt resistor 1 can be reduced.

[0082] Figure 8 1 is a top view showing an embodiment of a shunt resistor 200 without a recess 12. The structure of the shunt resistor 200 is the same as that of the shunt resistor 1 except that the shunt resistor 200 does not have the recess 12. That is, the shunt resistor 200 includes a resistor 205 equivalent to the resistor 5 of the shunt resistor 1 and a pair of electrodes 206 and 207 connected to both ends of the resistor 205. The electrodes 206 and 207 are equivalent to the electrodes 6 and 7 of the shunt resistor 1. The shunt resistor 200 includes a protrusion 211 equivalent to the protrusion 11 of the shunt resistor 1, and the protrusion 211 includes a part of the resistor 205 and a part of the electrodes 206 and 207. The protrusion 211 includes voltage detection parts 220 and 221 as parts of the electrodes 206 and 207 arranged symmetrically with respect to the resistor 205.

[0083] Fig. 9 : is a graph showing the relationship between the length t3 of the protrusion 211 in the second direction and the resistance value change rate of the shunt resistor 200 . Fig. 9 Indicates for Figure 8 The shape of the shunt resistor shown is the result of using a copper-manganese alloy as the resistor 205. Fig. 9 The vertical axis represents the resistance value change rate when the temperature of the shunt resistor 200 rises from 25° C. to 100° C. Fig. 9 The results show that the resistance value change rate of the shunt resistor 200 depends on the length t3. More specifically, the larger the length t3 is, the lower the resistance value change rate is.

[0084] Fig.10 : is a graph showing the relationship between the length t1 of the protrusion 11 of the shunt resistor 1 and the resistance value change rate of the shunt resistor 1 . Fig.10 Indicates for Figure 2 The shape of the shunt resistor shown is the result of using a copper-manganese alloy as the resistor 5. The length t2 of the recess 12 is the same as the length t1. Fig.10 The vertical axis represents the resistance value change rate when the temperature of the shunt resistor 1 rises from 25° C. to 100° C. Fig.10 The results and Fig. 9 The results show that the resistance change rate of the shunt resistor 1 depends on the length t1. The larger the length t1, the lower the resistance change rate. For example, when the length t1 is 2 mm, the resistance change rate of the shunt resistor 1 is approximately 0%.

[0085] In addition, if Fig.10 As shown in FIG. 1 , the ratio of the resistance value change rate of the shunt resistor 1 to the decrease is Fig. 9 The ratio of the resistance value change rate of the shunt resistor 200 shown is the same. That is, Fig.10 The results show that the resistance value change rate depending on the temperature of the shunt resistor 1 is independent of the recess 12 and depends on the length t1 of the protrusion 11. Therefore, Fig.10 The results show that by adjusting the length t1, the resistance temperature coefficient of the shunt resistor 1 can be corrected and the resistance temperature coefficient can be reduced.

[0086] Fig.11 : is a graph showing the resistance value change rate of each of the shunt resistor 1 and the shunt resistor 200 . Fig.11 The figure shows the rate of change of the resistance value of the shunt resistor 1 or 200 at a predetermined temperature (constant temperature) caused by the change of the length t1 or t3 of the protrusion 11 or 211. The length t2 of the recess 12 is the same as the length t1. Fig.11 The results show that, in the shunt resistor 200 without the recess 12, the resistance value varies greatly depending on the length t3 of the protrusion 211. For example, the resistance value of the shunt resistor 200 when the length t3 is 1.5 mm is about 8% lower than the resistance value when the length t3 is 0 mm. This is because the length of the resistor 205 in the second direction becomes longer by forming the protrusion 211, and the resistance value of the resistor 205 changes.

[0087] like Fig.11As shown in FIG. 1 , in the shunt resistor 1 having the recess 12, the change in the resistance value of the shunt resistor 1 caused by the change in the length t1 is suppressed. This is because the length of the resistor 5 in the second direction is kept constant by forming the recess 12 having the side surface 5d of the resistor 5. That is, by forming the recess 12, the change in the resistance value of the shunt resistor 1 caused by the formation of the protrusion 11 can be suppressed.

[0088] Therefore, by adjusting the length t1 of the protrusion 11 and the length t2 of the recess 12 of the shunt resistor 1 in accordance with the size and shape of the shunt resistor 1, it is possible to maintain a desired resistance value and satisfy a desired TCR. Therefore, according to the present embodiment, a protrusion 11 having a portion of the resistor 5 and a portion of the electrodes 6 and 7 is formed on the side 1a of the shunt resistor 1, and a recess 12 having a side 5d of the resistor 5 is formed on the side 1b of the shunt resistor 1. With only the simple structure described above, it is possible to maintain a desired resistance value and reduce the resistance temperature coefficient of the shunt resistor 1.

[0089] Fig.12 is a perspective view showing another embodiment of the shunt resistor 1. Fig.13 yes Fig.12 The structure of this embodiment not specifically described is different from that of the reference Figure 1 to Figure 3 The embodiment described is the same as that described above, so the repeated description thereof is omitted. The resistor 5 of this embodiment has a notch 25. The notch 25 is parallel to the end faces 5a and 5b (along the Figure 2 The notch 25 has a slit-like shape extending in a straight line. The notch 25 is formed on the side surface 5c of the resistor 5 and extends in a straight line from the side surface 5c toward the inside of the shunt resistor 1 (the center of the shunt resistor 1).

[0090] By forming such a notch 25 in the resistor 5, the resistance value of the shunt resistor can be adjusted, and in addition, the TCR of the shunt resistor 1 can be fine-tuned. Specifically, the narrower the width W3 of the notch 25 in the first direction and the longer the length t4 in the second direction, the greater the TCR can be. In this embodiment, the reference Figure 4 and Figure 5 The current detection device 30 described above and the reference Figure 6 The voltage detection terminals 38 and 39 are described.

[0091] Next, a method for manufacturing the shunt resistor 1 will be described. Fig.14 (a)~ Fig.14 (f) is a diagram showing an example of a manufacturing process of the shunt resistor 1. Fig.14 (a)~ Fig.14In (f), the bolt holes 8 and 9 are omitted.

[0092] First, if Fig.14 As shown in (a), a longitudinally long (strip-shaped) shunt resistor base material 60 (metal plate) is prepared in a state where the resistor 5 is connected to electrodes 6 and 7 at both ends in the first direction. Fig.14 As shown in (b), the shunt resistor base material 60 is cut in the direction in which the electrodes 6, the resistor body 5, and the electrodes 7 are arranged (i.e., the first direction). Specifically, the shunt resistor base material 60 is cut along the first direction and in a convex shape. The convex shape is a shape corresponding to the protrusion 11 of the shunt resistor 1. By cutting the shunt resistor base material 60 along the first direction and in a convex shape, the side 1a and the protrusion 11 ( Fig.14 (c)).

[0093] Next, if Fig.14 As shown in (c), the protrusion 11 and the side surface 1a are spaced apart in the second direction. Fig.14 (b) Similarly, the shunt resistor base material 60 is cut along the first direction and in a convex shape. As a result, the first shunt resistor 1A is cut away from the shunt resistor base material 60, and the side surface 1b of the first shunt resistor 1A, the concave portion 12 of the first shunt resistor 1A, the protruding portion 11 of the other shunt resistor 1 (the second shunt resistor 1B), and the side surface 1a of the second shunt resistor 1B are formed. Fig.14 (d)).

[0094] Next, if Fig.14 (e) and Fig.14 As shown in (f), Fig.14 (c) and Fig.14 (d) Similarly, the shunt resistor base material 60 is cut in the first direction and in a convex shape at a distance from the protrusion 11 and the side surface 1a of the second shunt resistor 1B in the second direction. As a result, the second shunt resistor 1B is cut away from the shunt resistor base material 60, and the side surface 1b of the second shunt resistor 1B and the concave portion 12 of the second shunt resistor 1B are formed. By repeating Fig.14 (c)~ Fig.14 The plurality of shunt resistors 1 are manufactured by the step (f).

[0095] pass Fig.14 (a)~ Fig.14 The manufacturing method shown in (f) can manufacture the shunt resistor 1 by a simple method, and can utilize the shunt resistor base material 60 without waste. As a result, cost reduction can be achieved.

[0096] Figure 15 to Figure 181 is a schematic diagram showing another embodiment of the shunt resistor 1. The structure of this embodiment not specifically described and the reference Figure 1 to Figure 3 The embodiments described are the same, so repeated descriptions are omitted. Figure 15 to Figure 18 In the figure, the bolt holes 8 and 9 are omitted. Figure 15 to Figure 18 In the embodiment shown, it is also possible to apply reference Figure 4 and Figure 5 The current detection device 30 described above and the reference Figure 6 The voltage detection terminals 38 and 39 are described.

[0097] In one embodiment, if Fig.15 As shown, the side surfaces 11a and 11b of the protrusion 11 and the side surfaces 12a and 12b of the recess 12 may also be aligned with respect to the second direction (see Figure 2 ) is formed obliquely. Fig.15 In the example shown, the side surfaces 11a and 11b extend in a direction away from the resistor 5. The side surface 12a is formed in parallel with the side surface 11a, and the side surface 12b is formed in parallel with the side surface 11b.

[0098] In one embodiment, if Fig.16 As shown in FIG. 1 , the voltage detection parts 20 and 21 may also have notches 20a and 21a extending from the side surfaces 11a and 11b toward the resistor 5, respectively. Fig.17 As shown, the width W2 of the recess 12 may also be greater than the width W1 of the protrusion 11, as shown in FIG. Fig.18 As shown, the width W2 may also be smaller than the width W1.

[0099] Fig.19 1 is a schematic diagram showing another embodiment of a method for manufacturing a shunt resistor 1. Fig.19 As shown in FIG. 1 , the shunt resistor 1 can also be manufactured by punching the shunt resistor base material 60 into the outer shape of the shunt resistor 1. Fig. 20 As shown, it can also be referenced by Fig.19 The same method as described is used to manufacture Fig.17 A shunt resistor 1 according to the embodiment shown.

[0100] Fig.21 is a perspective view showing another embodiment of the current detection device 30, Fig. 22 yes Fig.21 1 is a side view of the current detection device 30 shown in FIG. The current detection device 30 of the present embodiment includes the shunt resistor 1. In other words, the current detection device 30 of the present embodiment is the shunt resistor 1 itself. Fig.21 and Fig. 22 The shunt resistor 1 shown represents the reference Figure 1 to Figure 7 as well as Figure 10 to Figure 20The structure of the shunt resistor 1 of this embodiment, which is not particularly described, is similar to that of the reference shunt resistor 1. Figure 1 to Figure 3 The described implementation modes are the same, so repeated descriptions thereof are omitted.

[0101] In the present embodiment, the electrodes 6 and 7 have first wall portions 66b and 67b along the first direction forming a part of the protrusion 11, and second wall portions 66a and 67a along the second direction forming a part of the protrusion 11. The first wall portions 66b and 67b are formed on the same plane as the side surface 5c of the resistor 5. The second wall portions 66a and 67a correspond to the side surfaces 11a and 11b. In the present embodiment, the first wall portion 66b and the first wall portion 67b have the same length, and the second wall portion 66a and the second wall portion 67a have the same length.

[0102] In electrode 6, a detection area 66 is divided by the first wall portion 66b, the second wall portion 66a, the boundary line between the protrusion 11 and the main body 6f of the electrode 6, namely the starting end portion 66c, and at least a portion of the contact surface 6a in contact with the resistor 5. In electrode 7, a detection area 67 is divided by the first wall portion 67b, the second wall portion 67a, the boundary line between the protrusion 11 and the main body 7f of the electrode 7, namely the starting end portion 67c, and at least a portion of the contact surface 7a in contact with the resistor 5.

[0103] The main body 6f, 7f is a portion other than the portion forming the protrusion 11 of the electrode 6, 7. In other words, the main body 6f, 7f is a portion forming the main current path. The main current is the main flow of the current. The current also flows through the protrusion 11, but mainly flows through the main body 6f, the main body of the resistor 5 (the portion of the resistor 5 other than the portion 14), and the main body 7f. The starting end is an imaginary straight line extending from the side 6c, 7c of the electrode 6, 7 (the main body 6f, 7f) toward the resistor 5.

[0104] like Fig.21 and Fig. 22 As shown in FIG. 1 , in this embodiment, the thickness of the electrodes 6 and 7 is thicker than the thickness of the resistor 5. Fig. 22 As shown, the back surfaces of the electrodes 6 and 7 are on the same plane as the back surface of the resistor 5, and the surfaces 6e and 7e of the electrodes 6 and 7 are located higher than the surface 5e of the resistor 5. The surface 6e of the electrode 6, the contact surface 6a, and the surface 5e of the resistor 5 form a step 18, and the surface 7e of the electrode 7, the contact surface 7a, and the surface 5e of the resistor 5 form a step 19. The steps 18 and 19 and the surface 5e form a space SP.

[0105] In other words, the detection areas 66 and 67 protrude in the thickness direction of the current detection device 30 (the thickness direction of the shunt resistor 1) compared to the resistor 5. The thickness direction of the current detection device 30 (shunt resistor 1) refers to the direction perpendicular to both the first direction and the second direction. According to the structure of such a shunt resistor 1, when a substrate such as a current detection circuit substrate 34 is placed on the surface of the shunt resistor 1, a gap (space SP) can be formed between the resistor 5 and the substrate. Thereby, it is possible to avoid the heat of the resistor 5 being directly transmitted to the substrate. In addition, it is also possible to configure wiring for voltage detection (for example, voltage signal wiring 46 and 47) on the space SP. There is no resistor 5 between the detection areas 66 and 67. Therefore, the current flowing in the shunt resistor 1 avoids the surface of the detection areas 66 and 67, so stable voltage detection can be performed. In one embodiment, the electrodes 6, 7 and the resistor 5 may also be of the same thickness. In another embodiment, the shunt resistor 1 may also not have a recess 12.

[0106] Fig.23 yes Fig.21 The enlarged view of the protrusion 11. Figure 1 to Figure 3 In the embodiment described above, the voltage detection parts 20 and 21 are the entire part of the protrusion 11 forming the electrodes 6 and 7. However, in the present embodiment, the voltage detection parts 20 and 21 are arranged in the detection areas 66 and 67 with a gap between the start end parts 66c and 67c. The position and shape of the voltage detection parts 20 and 21 are not limited to Fig.23 The position and shape shown.

[0107] Fig.24 2 is a schematic diagram for explaining the positions of the voltage detection units 20 and 21. Fig.25 Yes means Fig.24 FIG. 1 is a graph showing the amount of change in the resistance value of the shunt resistor 1 due to temperature change at each detection position. Fig.25 is Fig.24 The simulation results of the temperature characteristics of the resistance value of the shunt resistor 1 when the voltage detection units 20 and 21 are configured at the detection positions A to D. In the simulation, the voltage drop of the shunt resistor 1 (the voltage of the resistor 5) is measured from the voltage detection units 20 and 21 at the detection positions A to D, and the resistance value of the shunt resistor 1 is calculated based on the measured voltage. In the simulation, it is assumed that the material of the resistor 5 is a Ni-Cr alloy. In addition, in the simulation, the length t1 of the second wall portion 66a, 67a and the length PW of the first wall portion 66b, 67b are both set to 2 mm.

[0108] For example, if the voltage detection units 20 and 21 are arranged at the starting end portions 66c and 67c, that is, arranged at the main current side (the main body 6f and 7f side), the temperature characteristic of the resistance value of the shunt resistor 1 obtained from the voltage detection units 20 and 21 is close to the temperature characteristic of the resistor 5 itself. Therefore, the detection position D is close to the starting end portions 66c and 67c, so the temperature characteristic of the shunt resistor 1 when the voltage detection units 20 and 21 are arranged at the detection position D becomes a characteristic close to the temperature characteristic of the resistor 5.

[0109] On the other hand, Fig.25 As shown, the further away the voltage detection parts 20 and 21 are from the starting parts 66c and 67c and closer to the terminal parts (first wall parts 66b and 67b), the more the inclination of the temperature characteristic rotates to the right (the slope of the temperature characteristic becomes smaller). For example, the temperature characteristic of the detection part D has a positive slope, which is relatively large, but by configuring the voltage detection parts 20 and 21 at the detection positions A to C, the slope of the temperature characteristic becomes smaller. In addition, as in the detection positions A and B, it is also possible to set a negative temperature characteristic (negative temperature characteristic). In this way, the temperature characteristic of the resistance value of the shunt resistor 1 changes according to the position of the voltage detection parts 20 and 21 in the second direction within the detection area 66 and 67.

[0110] In particular, between the detection position B and the detection position C, there is a region where the slope of the temperature characteristic of the resistance value of the shunt resistor 1 (i.e., TCR) is approximately 0 in a wide temperature range. The detection portion C is a position 0.5 mm away from the starting end portions 66c, 67c, and the detection position B is a position 1.0 mm away from the starting end portions 66c, 67c. Therefore, by configuring the voltage detection portions 20, 21 at a position more than 0.5 mm away from the starting end portions 66c, 67c, a good TCR characteristic can be obtained. The distance from the starting end portions 66c, 67c where the voltage detection portions 20, 21 are configured is preferably greater than 0.5 mm and less than 1.0 mm.

[0111] As described above, TCR changes depending on the positions of the voltage detection parts 20 and 21. Therefore, in the design and manufacturing process of the shunt resistor 1, the characteristic deviation of the resistor material (the material of the resistor body 5) itself and the processing deviation of the resistor material can be corrected by the positions of the voltage detection parts 20 and 21.

[0112] For example, the reference position of the voltage detection parts 20 and 21 is determined corresponding to the temperature characteristics of the predetermined resistor material. Then, when the actual temperature characteristics of the resistor material are observed to be on the positive side compared with the assumption, the voltage detection parts 20 and 21 are adjusted to be closer to the terminal part (first wall part 66b and 67b) than the reference position. In addition, when the temperature characteristics of the resistor material are observed to be on the negative side compared with the assumption, the voltage detection parts 20 and 21 are adjusted to be closer to the starting end parts 66c and 67c. By doing so, the characteristic deviation of the resistor material can be corrected by adjusting the position of the voltage detection parts 20 and 21.

[0113] As described above, in this embodiment, the desired resistance temperature coefficient can be satisfied by arranging the voltage detection parts 20 and 21 at desired positions with gaps between the detection areas 66 and 67 of the electrodes 6 and 7 constituting a part of the protrusion 11 of the current detection device 30 and the starting ends 66c and 67c.

[0114] Fig.26A and Fig.26B Schematic diagram showing another embodiment of the current detection device 30. The structure of this embodiment not specifically described is similar to that of the reference Figure 21 to Figure 25 The embodiments described are the same, so the repeated description is omitted. Fig.26A and Fig.26B As shown, the current detection device 30 of this embodiment includes a shunt resistor 1 and a wiring substrate 33. The wiring substrate 33 includes detection pads 33a and 33b. An unillustrated wiring for transmitting a voltage signal (voltage of the resistor 5) from the shunt resistor 1 is formed on the wiring substrate 33, and the detection pads 33a and 33b are connected to the unillustrated wiring.

[0115] The detection pads 33a and 33b are thin metal films and are connected to the voltage detection parts 20 and 21 (in Fig.26A and Fig.26B (not shown) connection. Fig.26B Indicates from Fig.26A The wiring substrate 33 is positioned in the second direction ( Fig.23 2. In the present embodiment, the portions on the detection regions 66 and 67 connected to the detection pads 33a and 33b serve as the voltage detection units 20 and 21.

[0116] like Fig.26A and Fig.26BAs shown, by adjusting the relative position of the shunt resistor 1 and the wiring substrate 33, the position of the detection pads 33a and 33b connected to the detection areas 66 and 67 can be adjusted. In other words, by adjusting the relative position of the shunt resistor 1 and the wiring substrate 33, the position of the voltage detection unit 20 and 21 can be adjusted. Therefore, by adjusting the relative position of the shunt resistor 1 and the wiring substrate 33, the TCR characteristic can be corrected. The width of the detection pads 33a and 33b in the second direction is smaller than t1, and is a size that can be adjusted in position. There is a tendency that the smaller the width of the detection pads 33a and 33b, the better the temperature characteristics of the shunt resistor 1, and the size of the detection pads 33a and 33b is set in consideration of the bonding and the risk of disconnection. It should be noted that if the position of the detection pads 33a and 33b is adjusted, the resistance value of the current detection device 30 can be changed, and it can also be applied to the correction function of the resistance value.

[0117] The method for aligning the wiring substrate 33 with the shunt resistor 1 is as follows. First, during the initial flow, a detection probe is used to measure the resistance value of the shunt resistor 1 at two points (or more than three points) as a reference temperature of 25°C (or 20°C) and a predetermined temperature (for example, 125°C) at a predetermined detection position, thereby measuring the inherent temperature characteristics of the shunt resistor 1. Thus, the connection position of the wiring substrate 33 is determined. The alignment of the wiring substrate 33 and the shunt resistor 1 can be performed by methods such as alignment based on image detection, setting reference pins on the shunt resistor 1 and the fixture to make the position variable, etc. In this way, a mechanism that can relatively control the initial characteristics and the voltage detection lead-out position can be constructed within the process.

[0118] Fig.27A and Fig.27B Schematic diagram showing another embodiment of the current detection device 30. The structure of this embodiment not specifically described is similar to that of the reference Figure 21 to Figure 25 The embodiments described are the same, so the repeated description is omitted. Fig.27A and Fig.27B As shown, the current detection device 30 of this embodiment includes a shunt resistor 1 and detection members 72, 73. The detection members 72, 73 and the voltage detection units 20, 21 (in the detection areas 66, 67) Fig.27A and Fig.27B (not shown) connection.

[0119] Fig.27B Indicates from Fig.27AThe positions of the detection members 72 and 73 are shifted in the second direction and the detection members 72 and 73 are connected to the detection regions 66 and 67. In the present embodiment, the portions on the detection regions 66 and 67 connected to the detection members 72 and 73 become the voltage detection parts 20 and 21. Examples of the detection members 72 and 73 include solder pads, pin terminals, lead frames, and the like made of soldering materials or other metals.

[0120] like Fig.27A and Fig.27B As shown, by adjusting the connection positions of the detection members 72 and 73, the voltage detection units 20 and 21 (in Fig.27A and Fig.27B (not shown in the figure). Therefore, by adjusting the position of the detection components 72 and 73, the TCR characteristics can be corrected. The width of the detection components 72 and 73 in the second direction is smaller than t1, and is a size that can be adjusted in position. There is a tendency that the smaller the width of the detection components 72 and 73, the better the temperature characteristics of the shunt resistor 1, and the size of the detection components 72 and 73 is set in consideration of the bonding and the risk of broken wires. It should be noted that if the position of the detection components 72 and 73 is adjusted, the resistance value of the current detection device 30 can be changed, and it can also be applied to the correction function of the resistance value.

[0121] Fig.28A and Fig.28B 2 is a diagram for explaining the positions of the voltage detection units 20 and 21. As described above, if the voltage detection units 20 and 21 are arranged at the starting ends 66c and 67c, the temperature characteristics of the resistance value of the shunt resistor 1 obtained from the voltage detection units 20 and 21 are similar to the temperature characteristics of the resistor 5 itself. Therefore, in the present embodiment, the voltage detection units 20 and 21 are arranged in the detection areas 66 and 67, avoiding the starting ends 66c and 67c.

[0122] In one embodiment, the voltage detection unit 20 is disposed at Fig.28A Although not shown, the voltage detection unit 21 is arranged symmetrically with respect to the resistor 5 and the voltage detection unit 20. Specifically, the voltage detection units 20 and 21 are arranged in the area of ​​3 / 4 of the terminal side (first wall portion 66b, 67b side) of the detection area 66 and 67 in the second direction.

[0123] As the material of the electrodes 6 and 7, Cu is generally used. However, in order to reduce the influence of the temperature characteristics of the resistance value of the electrode material, in one embodiment, Fig.28B As shown in FIG. 1 , the voltage detection units 20 and 21 may be arranged on the side closer to the resistor 5 than the center (center line CL) of the detection regions 66 and 67 in the first direction. Specifically, the voltage detection unit 20 may be arranged on the side closer to the resistor 5 than the center (center line CL) of the detection regions 66 and 67 in the first direction. Fig.28BAlthough not shown in the figure, the voltage detection unit 21 is arranged symmetrically with respect to the resistor 5 and the voltage detection unit 20. Fig.28B The region 75 is a region that is 3 / 4 of the terminal end side (first wall portion 66 b , 67 b side) of the detection regions 66 , 67 in the second direction and is a region that is 1 / 2 of the resistor 5 side of the detection regions 66 , 67 in the first direction.

[0124] As described above, in this embodiment, the shunt resistor 1 has the steps 18 and 19. Therefore, in one embodiment, a voltage detection member for detecting the voltage of the resistor 5 may be connected across the steps 18 and 19 (in a manner covering the contact surfaces 6a and 7a). As a result, the influence of the temperature characteristics of the resistance value of the material of the electrodes 6 and 7 can be further reduced, and the voltage generated at the two ends 5a and 5b of the resistor 5 can be measured with better accuracy. In addition, the steps 18 and 19 can be used to prevent the voltage detection member from contacting the resistor 5.

[0125] Fig.29 18 and 19. The schematic diagram shows an example in which a voltage detection member is connected across steps 18 and 19. In the present embodiment, the current detection device 30 includes a wiring substrate 33 and a shunt resistor 1. The wiring substrate 33 includes detection pads 33a and 33b as voltage detection members. The detection pads 33a and 33b are connected to the voltage signal wirings 48 and 49 via through holes 52 and 53. The detection pads 33a and 33b are connected to the detection areas 66 and 67 across the steps 18 and 19 (in a manner covering the contact surfaces 6a and 7a). With such a structure, the inner side of the electrodes 6 and 7 can be set as the voltage detection section 20 and 21 (at Fig.29 (not shown in the figure), the voltage of the resistor 5 can be measured without being affected by the characteristics of the electrodes 6 and 7. As a result, in this embodiment, the voltage generated at the two ends 5a and 5b of the resistor 5 can be measured with better accuracy.

[0126] As described above, the resistor 5 is connected to the electrodes 6 and 7 by welding (for example, electron beam welding, laser beam welding, or soldering). Therefore, the joints between the resistor 5 and the electrodes 6 and 7 are uneven due to welding marks, but in this embodiment, the shunt resistor 1 has steps 18 and 19, so the voltage detection member can be connected across the steps 18 and 19 without being affected by the welding marks.

[0127] Fig.301 is a schematic diagram showing another embodiment of the protrusion 11. There is also a case where it is not necessary to set the temperature characteristic of the resistance value of the shunt resistor 1 to have a characteristic with a negative slope. In this case, the length t1 of the second wall portions 66a and 67a may not be longer than necessary. By shortening the length t1 of the second wall portions 66a and 67a, it is possible to contribute to the miniaturization and cost reduction of the shunt resistor 1. In one embodiment, as Fig.30 As shown in FIG. 1 , the length PW of the first wall portions 66b and 67b may be longer than the length t1 of the second wall portions 66a and 67a. For example, PW:t1 may be set to 4:3 or PW:t1 may be set to 3:2.

[0128] In another embodiment, Fig.31 As shown in FIG. 1 , the corners of the protrusion 11 may be rounded. In this embodiment, the ratio of t1 to the length of PW may also be Fig.30 In another embodiment, the angle of the protrusion 11 may be set as a C-plane. In this case, the ratio of the length of t1 to PW may also be Fig.30 The implementation method is the same.

[0129] Fig.32 Schematic diagram showing another embodiment of the current detection device 30. The structure of this embodiment not specifically described is similar to that of the reference Figure 21 to Figure 31 The embodiments described are the same, so the repeated description thereof is omitted. In the present embodiment as well, the current detection device 30 includes the shunt resistor 1. In other words, the current detection device 30 of the present embodiment is the shunt resistor 1 itself. In the present embodiment, slits 76 and 77 are formed in the electrodes 6 and 7. In addition, in the present embodiment, the shunt resistor 1 does not have the recess 12. Specifically, the slits 76 and 77 extend from the side surfaces 6c and 7c toward the inner side of the electrodes 6 and 7 (along the second direction (refer to Fig.21 ) extends). In this embodiment, the protrusion 11 is formed by the slits 76 and 77. In this embodiment, it is also possible to apply Figure 26A to Figure 31 implementation method, which can generate reference Figure 21 to Figure 31 The effect of the description.

[0130] The above-mentioned embodiments are recorded for the purpose of enabling a person with common knowledge in the technical field to which the present invention belongs to implement the present invention. Various modifications of the above-mentioned embodiments can certainly be implemented by a person skilled in the art, and the technical idea of ​​the present invention can also be applied to other embodiments. Therefore, the present invention is not limited to the described embodiments, and should be interpreted within the broadest scope based on the technical idea defined by the claims.

[0131] Industrial Applicability

[0132] The present invention can be used in a current detection device, in particular, a current detection device using a shunt resistor.

[0133] Description of Reference Numerals

[0134] 1. Shunt resistor; 1A, 1st shunt resistor; 1B, 2nd shunt resistor; 1a, 1b, side; 5, resistor body; 5a, 5b, both ends (connecting surfaces on both sides); 5c, 5d, side; 5e, surface; 6, 7, electrodes; 6a, 7a, contact surface; 6b, 6c, 6d, side; 7b, 7c, 7d, side; 6e, 7e, surface; 6f, 7f, body; 8, 9, bolt holes ; 11, protrusion; 11a, 11b, side; 12, recess; 12a, 12b, 12c, side; 14, part; 16, 17, voltage detection position; 18, 19, step; 20, 21, voltage detection part; 20a, 21a, notch; 25, notch; 30, current detection device; 31, voltage output device; 32, housing; 33, wiring substrate; 33a, 33b, detection pad; 34, current detection circuit substrate; 35, output terminal; 36, 37, voltage terminal pad; 38, 39, voltage detection terminal; 46, 47, voltage signal wiring; 48, 49, voltage signal wiring; 50, ground wiring; 52, 53, through hole; 60, shunt resistor base material; 66, 67, detection area; 66a, 67a, second wall; 66b, 67b, first wall; 6 6c, 67c, starting end; 72, 73, detection component; 75, area; 76, 77, slit; 100, shunt resistor; 105, resistor body; 106, 107, electrode; 108, 109, bolt hole; 120, 121, voltage detection part; 200, shunt resistor; 205, resistor body; 206, 207, electrode; 211, protrusion; 220, 221, voltage detection part.

Claims

1. A current detection device, used for current detection, wherein: The current detection device has: Resistor; as well as A pair of electrodes connected to both ends of the resistor in the first direction, The current detection device has a protrusion protruding in a second direction, The protrusion has a portion of the resistor and a portion of the pair of electrodes. The first direction is a direction in which the pair of electrodes are arranged, and the second direction is a direction perpendicular to the first direction. Each electrode has a first wall portion along the first direction forming a part of the protrusion and a second wall portion along the second direction forming a part of the protrusion. In each of the electrodes, a detection area is divided by the first wall portion, the second wall portion, the boundary between the protrusion and the main body of the electrode, that is, the starting end portion, and at least a portion of the contact surface that contacts the resistor. Each of the electrodes has a voltage detection portion provided in the detection region.

2. The current detection device according to claim 1, wherein: The voltage detection unit is arranged in the detection region at a distance of 0.5 mm or more from the start end portion.

3. The current detection device according to claim 1 or 2, wherein: A wiring substrate is provided on which wiring for transmitting the voltage signal of the voltage detection unit is formed, The wiring substrate overlaps the protruding portion.

4. The current detection device according to claim 3, wherein: The voltage detection portion is a pin terminal.

5. The current detection device according to claim 4, wherein: A wiring substrate is provided on which wiring for transmitting the voltage signal of the voltage detection unit is formed, The pin terminal passes through a through hole formed in the wiring substrate.

6. The current detection device according to claim 2, wherein: The voltage detection portion is not in contact with the second wall portion.

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