Shunt resistor, method for manufacturing shunt resistor, and current detection device

Abstract

The present invention relates to a shunt resistor and a method for manufacturing the shunt resistor. In addition, the present invention relates to a current detection device having a shunt resistor. The shunt resistor (1) has a resistor (5) and a pair of electrodes (6, 7) connected to both ends (5a, 5b) of the resistor (5) in a first direction, the shunt resistor (1) having: a protrusion (11) formed on a side surface (1a) of the shunt resistor (1) which is a surface parallel to the first direction; and a recess (12) formed on a side surface (1b) of the shunt resistor (1) which is a surface opposite to the side surface (1a) and extending in the same direction as the protrusion (11), the protrusion (11) having a portion of the resistor (5) and a portion of the pair of electrodes (6, 7), and the recess (12) having a side surface (5d) of the resistor (5) which is parallel to the first direction.

Description

Technical Field

[0001] The present invention relates to a shunt resistor and a method for manufacturing the shunt resistor. In addition, the present invention relates to a current detection device including the shunt resistor. Background Art

[0002] 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.

[0003] Fig.21 and Fig. 22 An example of a conventional shunt resistor is shown in FIG. Fig.21 and Fig. 22 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.

[0004] The shunt resistor 100 further includes voltage detection units 120 and 121 for measuring the voltage of the resistor 105. Fig.21 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.

[0005] exist Fig. 22 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 .

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2017-5204

[0009] Patent Document 2: Japanese Patent Application Publication No. 2007-329421 Summary of the invention

[0010] Problem that the invention aims to solve

[0011] In a shunt resistor, in order to detect current under conditions where the influence of temperature changes is small, the characteristics of the temperature coefficient of resistance (TCR) are important. It should be noted that the temperature coefficient of resistance is an indicator that represents the ratio of the change in resistance value caused by temperature. Therefore, an object of the present invention is to provide a shunt resistor that can reduce the temperature coefficient of resistance with a simple structure. In addition, an object of the present invention is to provide a method for manufacturing such a shunt resistor and a current detection device having such a shunt resistor.

[0012] Solutions for solving problems

[0013] In one technical solution, 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.

[0014] In one embodiment, 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.

[0015] In one embodiment, the protrusion includes a pair of voltage detection parts connected to both ends of the resistor in the first direction.

[0016] In one embodiment, the protrusion and the recess have a rectangular shape.

[0017] In one technical solution, 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 where 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.

[0018] In one technical solution, 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.

[0019] In one embodiment, 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.

[0020] In one embodiment, the current detection device further includes an output terminal for outputting a voltage signal from the shunt resistor, and the output terminal is mounted in a recessed portion of the shunt resistor.

[0021] Effects of the Invention

[0022] A protrusion having a portion of the resistor body and a portion of a pair of electrodes is formed on the first side of the shunt resistor, and a recess having a side surface of the resistor body parallel to the first direction is formed on the second side of the shunt resistor. With only the above simple structure, the desired resistance value can be maintained while reducing the resistance temperature coefficient of the shunt resistor. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a perspective view showing one embodiment of a shunt resistor.

[0024] Figure 2 yes Figure 1 A top view of a shunt resistor is shown.

[0025] Figure 3 It is an enlarged view of the protrusion and the recess.

[0026] Figure 4 It is a perspective view showing one embodiment of a current detection device including a shunt resistor.

[0027] Figure 5 This is a perspective view showing the current detection device with the case of the voltage output device removed.

[0028] Figure 6 This is a schematic diagram showing a state where a voltage detection terminal is provided in the voltage detection unit.

[0029] Figure 7 This is a graph showing the rate of change of the resistance value of the shunt resistor due to temperature change.

[0030] Figure 8 It is a plan view showing one embodiment of a shunt resistor having no recessed portion.

[0031] 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.

[0032] 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.

[0033] Fig.11 This is a graph showing the rate of change of the resistance value of the shunt resistor.

[0034] Fig.12 It is a perspective view showing another embodiment of the shunt resistor.

[0035] Fig.13 yes Fig.12 Magnified view of the protrusion.

[0036] Fig.14 This is a diagram showing an example of a manufacturing process of a shunt resistor.

[0037] Fig.15 It is a schematic diagram showing still another embodiment of the shunt resistor.

[0038] Fig.16 It is a schematic diagram showing still another embodiment of the shunt resistor.

[0039] Fig.17 It is a schematic diagram showing still another embodiment of the shunt resistor.

[0040] Fig.18 It is a schematic diagram showing still another embodiment of the shunt resistor.

[0041] Fig.19 It is a schematic diagram showing another embodiment of the method for manufacturing a shunt resistor.

[0042] Fig. 20 It is a schematic diagram showing another embodiment of the method for manufacturing a shunt resistor.

[0043] Fig.21 It is a diagram showing an example of a conventional shunt resistor.

[0044] Fig. 22 It is a diagram showing an example of a conventional shunt resistor. DETAILED DESCRIPTION

[0045] 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.

[0046] 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.

[0047] 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 .

[0048] 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.

[0049] 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).

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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).

[0057] 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.

[0058] 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 conductive wire (for example, an aluminum wire) to the voltage detection terminals 38 and 39, or by passing the voltage detection terminals 38 and 39 through a through hole formed in the circuit substrate and conducting and connecting 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.

[0059] Figure 7 It 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.21 The resistance value change rate of the shunt resistor 100) shown. Figure 7The results are shown when a copper-manganese alloy is used as the resistor 5 .

[0060] 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 results show 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.

[0061] 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.

[0062] 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.

[0063] 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.10The 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%.

[0064] 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.

[0065] 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.

[0066] like Fig.11 As 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.

[0067] 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.

[0068] 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).

[0069] 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.

[0070] 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.14 In (f), the bolt holes 8 and 9 are omitted.

[0071] 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.14As 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)).

[0072] 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)).

[0073] 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).

[0074] 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.

[0075] Figure 15 to Figure 18 1 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.

[0076] 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.

[0077] 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.

[0078] 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.

[0079] 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 those 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.

[0080] Industrial Applicability

[0081] The present invention can be used for a shunt resistor and a method for manufacturing the shunt resistor. In addition, the present invention can be used for a current detection device including the shunt resistor.

[0082] Description of Reference Numerals

[0083] 1. Shunt resistor; 1A. First shunt resistor; 1B. Second shunt resistor; 1a, 1b, side; 5. Resistor; 5a, 5b, both ends (connection surfaces on both sides); 5c, 5d, side; 6, 7. Electrode; 6a, 7a, contact surface; 6b, 6c, 6d, side; 7b, 7c, 7d, side; 8, 9. Bolt hole; 11. Protrusion; 11a, 11b, side; 12. Recess; 12a, 12b, 12c, side; 14. Position; 16, 17, voltage detection position; 20, 21, voltage detection part; 20a, 21a, notch; 25, notch; 3 0. Current detection device; 31. Voltage output device; 32. Shell; 34. Current detection circuit substrate; 35. Output terminal; 36, 37. Voltage terminal pad; 38, 39 Voltage detection terminal; 46, 47. Voltage signal wiring; 50. Ground wiring; 60. Shunt resistor base material; 100. Shunt resistor; 105. Resistor; 106, 107. Electrode; 108, 109. Bolt hole; 120, 121. Voltage detection unit; 200. Shunt resistor; 205. Resistor; 206, 207. Electrode; 211. Protrusion; 220, 221. Voltage detection unit.

Claims

1. A shunt resistor is a plate-shaped shunt resistor used for current detection, wherein: The shunt resistor has: Resistor; as well as A pair of electrodes connected to both ends of the resistor in the first direction, The shunt resistor has: a first side surface of the shunt resistor along the first direction; a second side surface located on a side opposite to the first side surface of the shunt resistor and along the first direction; a protrusion formed on the first side surface and having a rectangular shape protruding in a second direction perpendicular to the first direction; and a recessed portion formed on the second side surface and having a rectangular shape recessed toward the second direction, The protrusion and the recess are formed to include the resistor and a part of the pair of electrodes, respectively. The protrusion and the recess are formed at overlapping positions in the second direction, The recessed portion is formed with a side surface parallel to the first direction and composed of the resistor and a part of the electrode. A pair of electrodes in the protruding portion connected to both ends of the resistor is used as a voltage detection portion.

2. The shunt resistor according to claim 1, wherein 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.

3. A method for manufacturing a shunt resistor, the shunt resistor comprising a resistor and a pair of electrodes connected to both ends of the resistor, wherein: A longitudinal shunt resistor base material is prepared in which a pair of electrodes are connected to both ends of the resistor in the first direction. The shunt resistor base material is cut along the first direction and in a convex shape, thereby forming a protruding portion of the first shunt resistor having a portion of the resistor body of the first shunt resistor and a portion of a pair of electrodes of the first shunt resistor, wherein the protruding portion has a rectangular shape protruding in a second direction perpendicular to the first direction on a first side surface along the first direction, The shunt resistor base material is cut in a convex shape along the first direction at intervals from the protruding portion, thereby forming a concave portion of the first shunt resistor and a protruding portion of the second shunt resistor extending in the same direction as the protruding portion, and the concave portion has a rectangular shape that is concave toward the second direction on the second side surface along the first direction, The protrusion and the recess of the first shunt resistor are formed at overlapping positions in the second direction, and the recess has a side surface formed by the resistor and a part of the electrode parallel to the first direction. The protruding portion of the second shunt resistor includes a portion of the resistor body of the second shunt resistor and a portion of a pair of electrodes of the second shunt resistor. A pair of electrodes in the protruding portion connected to both ends of the resistor is used as a voltage detection portion.

4. A current detection device, wherein: The current detection device has: The shunt resistor according to claim 1 or 2; as well as a current detection circuit substrate having a voltage signal wiring for transmitting a voltage signal from the shunt resistor, The voltage signal wiring is electrically connected to the protruding portion of the shunt resistor.

5. The current detection device according to claim 4, wherein: The current detection circuit substrate further comprises a pad for a voltage terminal. The voltage terminal pad is connected to the protruding portion and the voltage signal wiring.

6. The current detection device according to claim 4 or 5, wherein: further comprising an output terminal for outputting a voltage signal from the shunt resistor, The output terminal is mounted in the recessed portion of the shunt resistor.

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