JP2017208475A - Shunt resistor and shunt type current detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shunt resistor and a shunt type current detector which, in connecting/fixing terminals of the shunt resistor to a bus bar by bolt fastening, can eliminate influence to joint surfaces of the resistor and the terminals due to bolt fastening, and can measure current highly accurately and highly reliably.SOLUTION: A shunt resistor 1 comprises: tabular terminals 11A, 11B made of a conductive metal material; and a resistor 12 which is made of a metal material having a smaller resistance-temperature coefficient than the terminals and fixed to the terminals, in which the terminals 11A, 11B have pores 15A, 15B penetrating in the thickness direction of the terminals, and provided with regions 16A, 16B which are formed around the pores and recessed in the thickness direction of the terminals, and comprise sidewalls 17 at least on one side along the longitudinal direction of the regions. Wiring members 20A, 20B are fitted with and fixed to the regions 16A, 16B which are formed around the pores and recessed in the thickness direction of the terminals 11A, 11B.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a shunt resistor that detects a current flowing through a resistor, and a current detection device that uses the shunt resistor.

  Resistors using shunt resistors are used to detect battery charge / discharge currents, motor currents that drive electric vehicles and hybrid vehicles, electric devices such as air conditioners, and power generation facilities such as solar cells. A current is detected by measuring a potential difference caused by energization of the current.

  In particular, a bus bar (Busbar) is used as a path for flowing current from a power source such as a battery to various electrical devices, and current detection may be performed by connecting a shunt resistor to the bus bar. In such a case, the bus bar and the shunt resistor, which are wiring members, may fix the terminal of the shunt resistor and the bus bar by screwing (bolt tightening) (see Patent Document 1).

  However, when connecting and fixing the end of the bus bar, which is a wiring member, and the terminal of the shunt resistor by bolting, the end of the bus bar and the terminal of the shunt resistor are correctly positioned (for example, linearly) by tightening the bolt. ) And the bus bar and the shunt resistor may be displaced (for example, fixed obliquely).

  And in a shunt resistor, there exists a thing of the structure which joined the long terminal and the resistor by welding, and the intensity | strength of the part joined by welding may be inferior compared with other places.

  When such a shunt resistor is to be connected and fixed to another bus bar (wiring member) by bolt tightening, stress may be applied to the welded portion of the terminal of the shunt resistor and the resistor due to the rotational force of the bolt tightening. As a result, there is a problem in that the junction state between the terminal of the shunt resistor and the resistor is affected and the accuracy of current detection is impaired.

JP 2011-3694 A

  The present invention has been made based on the above circumstances, and eliminates the influence of the bolting on the joint surface of the resistor and the terminal when the terminal of the shunt resistor is connected and fixed to the bus bar (wiring member) by bolting. An object of the present invention is to provide a shunt resistor and a current detection device capable of measuring current with high accuracy and high reliability.

  The shunt resistor of the present invention includes a plate-like terminal made of a conductive metal material, and a resistor made of a metal material having a smaller temperature coefficient of resistance than the terminal, and fixed to the terminal. And having a hole penetrating in the thickness direction of the terminal, providing a region formed around the hole and recessed in the thickness direction of the terminal, and having a side wall on at least one side along the longitudinal direction of the region. Features. The shunt-type current detection device of the present invention includes the shunt resistor and a wiring member made of a conductive metal material, and the wiring member is formed around the hole and extends in the thickness direction of the terminal. It is characterized by being fitted and fixed in the recessed area.

  According to the present invention, when the terminal of the shunt resistor is connected and fixed to the bus bar (wiring member) by bolting, the end of the bus bar (wiring member) is fitted into the recessed region formed in the terminal, and the hole is formed. Since the bolts that penetrate are fixed by tightening, even if the bolts are strongly tightened, the movement of the end portion of the bus bar (wiring member) is restricted by the side wall. As a result, the end of the bus bar (wiring member) and the terminal of the shunt resistor are fixed in the correct position, and the bonding state between the terminal of the shunt resistor and the resistor is affected, and the current detection accuracy is impaired. Solved.

It is a perspective view of the surface side of the shunt resistor of Example 1 of this invention. It is a perspective view of the back surface side of the shunt resistor of Example 1 of the present invention. It is a disassembled perspective view which connects the said shunt resistor to another bus bar. It is sectional drawing along the AA line of FIG. It is a perspective view of the surface side of the shunt resistor of Example 2 of this invention. It is a perspective view of the back surface side of the shunt resistor of Example 2 of the present invention. It is a disassembled perspective view which connects the said shunt resistor to another bus bar. It is sectional drawing along the AA line of FIG. It is a perspective view of the surface side of the shunt resistor of Example 3 of this invention. It is the perspective view which connected the said shunt resistor to other bus bars. It is a perspective view of the surface side of the shunt resistor of Example 4 of this invention. It is the perspective view which connected the said shunt resistor to other bus bars. It is a disassembled perspective view of the shunt resistor of Example 5 of this invention, and another bus bar. It is the perspective view which connected the said shunt resistor to other bus bars. It is sectional drawing along the BB line of FIG. It is a disassembled perspective view of the shunt resistor of Example 6 of this invention, and another bus bar. It is the perspective view which connected the said shunt resistor to other bus bars. It is sectional drawing along the BB line of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1A to 16. In addition, in each figure, the same code | symbol is attached | subjected and demonstrated to the same or equivalent member or element.

  1A and 1B show a shunt resistor according to Embodiment 1 of the present invention. The shunt resistor 1 includes a pair of terminals 11A and 11B made of a highly conductive metal material such as Cu and a metal material having a resistance temperature coefficient smaller than that of the terminals, and is a resistor fixed between the terminals 11A and 11B. A body 12 is provided. The resistor 12 is preferably made of a metal material having a resistance temperature coefficient smaller than that of a metal material such as Cu, such as Cu—Mn—Ni, Cu—Ni, or Ni—Cr.

  Both end surfaces of the resistor 12 are welded to the end surfaces of the terminal 11 </ b> A and the end surfaces of the terminal 11 </ b> B by abutting each other to form a joint surface. For welding, electron beam welding, laser beam welding, brazing, or the like is used. Note that a structure or a manufacturing method in which the end face of the resistor and the end face of the wiring member are overlapped and pressed to form a joint surface may be used.

  Voltage terminals 13 </ b> A and 13 </ b> B are provided in the vicinity of the resistor 12 at the terminals 11 </ b> A and 11 </ b> B on both sides of the resistor 12. Therefore, the current flowing through the terminals 11A and 11B passes through the resistor 12, and the potential difference between both ends is detected by the voltage terminals 13A and 13B. The terminals 11A and 11B are long and the shunt resistor 1 is a shunt resistor having a predetermined length in which a resistor 12 is incorporated between the terminals 11A and 11B.

  Therefore, the long terminals 11A and 11B serve as electrodes, and the current flowing between the terminals 11A and 11B is measured with high accuracy and reliability by integrating the functions of the bus bar and the shunt resistor. It becomes possible.

  The both ends of the terminals 11A and 11B on both sides of the resistor 12 are provided with connecting portions to other bus bars (wiring members), batteries and other devices. As shown in the figure, the connecting portion includes holes 15A and 15B and regions 16A and 16B that are recessed on the back surface. The recessed regions 16A and 16B have a side wall 17 around them. The side wall 17 is formed along the longitudinal direction of the regions 16A and 16B (which also coincides with the longitudinal direction of the terminals). In the present embodiment, the side wall 17 is also formed in the terminal portions inside the regions 16A and 16B. And the recessed area | regions 16A and 16B have the open part 18 in the edge part of terminal 11A, 11B. In this embodiment, the side walls 17 are formed on both sides of the regions 16A and 16B. However, if the side walls 17 are formed on one of the regions 16A and 16B, the effect of the present invention can be obtained.

  The recessed regions 16A and 16B are formed by cutting, pressing or the like. In this example, it is formed on the back surface opposite to the surface on which the voltage terminals 13A and 13B are formed, but may be formed on the same surface as the surface on which the voltage terminals 13A and 13B are formed.

  FIG. 2 shows a state in which the shunt resistor 1 is connected between the wiring members (bus bars) 20A and 20B, and FIG. 3 shows an AA cross section of FIG. As shown in the figure, the ends of the wiring members (bus bars) 20A and 20B made of a pair of conductive metal materials are fitted into the recessed regions 16A and 16B of the terminals 11A and 11B, and the bottom surface of the recessed region and the three side walls. 17 is fixed in contact with.

  Then, the bolt 21 passes through the holes 15B and 15b and the nuts 22 are tightened so that the tips of the wiring members (bus bars) 20A and 20B are fitted into predetermined positions (recessed regions 16A and 16B) of the terminals 11A and 11B. Fixed together.

  That is, the end portions of the wiring members (bus bars) 20A and 20B are fitted into the side walls 17 of the regions 16A and 16B, which are partially recessed in the thickness direction. Then, one surface of the end portions of the wiring members (bus bars) 20A and 20B is in contact with the bottom surfaces of the recessed regions 16A and 16B. Then, the three surfaces of the end portions of the wiring members (bus bars) 20A and 20B are in contact with the side walls 17 and positioned.

  For this reason, when the terminal of the shunt resistor is connected and fixed to the bus bar (wiring member) by bolting, even if the bolt is tightened strongly, the movement of the end portion of the bus bar (wiring member) is restricted by the side wall of the terminal. This solves the problem that the end of the bus bar (wiring member) and the terminal of the shunt resistor are connected and fixed at the correct positions, and the bus bar (wiring member) and the shunt resistor are displaced.

  That is, when there is no conventional recessed area, the bus bar and shunt resistor may be misaligned by tightening the bolt, and stress is applied to the welded portion of the shunt resistor terminal and resistor. There is. As a result, the bonding state between the terminal and the resistor is affected, and there is a problem that the accuracy of current detection is impaired, but the above problem is solved by restricting the movement of the wiring member in the recessed area provided in the terminal. Is done.

  4A and 4B show the front and back surfaces of the shunt resistor of the second embodiment, and FIG. 5 shows a state in which the end of the shunt resistor 2 is connected to the other bus bars 20A and 20B. The difference from the first embodiment is that, as shown in FIGS. 4A and 4B, regions 16A and 16B that are recessed over the entire length of the terminals 11A and 11B are formed.

  The terminals 11A and 11B in which the recessed regions 16A and 16B are formed over the entire length are formed by a deformed wire drawing technique. The irregular shape drawing technique is a technique for drawing a long material having an irregular cross-sectional shape using a die or a roll. As shown in the drawing, a long material in which recessed regions 16A and 16B are formed can be manufactured continuously, and the terminals 11A and 11B can be manufactured by cutting them into appropriate dimensions.

  Compared with the first embodiment, secondary processing by a press for forming a recessed region is not necessary, and the terminals 11A and 11B having the recessed regions 16A and 16B can be easily mass-produced. And as shown in FIG. 6, the edge part of 20 A of wiring members (bus bar) fits in the side wall 17 of the area | region 16A in which the part was dented in the thickness direction.

  Accordingly, as in the first embodiment, the side portions of the wiring members (bus bars) 20A and 20B are in contact with the side walls 17 and are fitted and fixed to the regions 16A and 16B that are recessed in the thickness direction of the terminals. Since the wiring member is positioned by the side wall 17 formed along the longitudinal direction of the regions 16A and 16B, the problem that the wiring member (bus bar) and the shunt resistor are displaced due to tightening of the bolt is solved. In this embodiment, the side walls 17 are formed on both sides of the regions 16A and 16B, but the side walls 17 may be formed only on one side. Further, when the area where the terminals 11A, 11B and the wiring members 20A, 20B overlap is increased in the length direction, positional deviation can be prevented. For example, the wiring members 20A and 20B can be easily stacked on the entire surface of the terminals 11A and 11B without being displaced. Thereby, the heat capacity of the shunt resistor is increased and heat generation can be suppressed.

  FIG. 7 shows a shunt resistor according to a third embodiment of the present invention. The shunt resistor 3 is an example in which a region 16B that is recessed so as to be substantially orthogonal to the arrangement direction of the terminals 11A and 11B with respect to the resistor 12 is formed. Although the example which formed the recessed area | region 16B only in one terminal 11B is shown, you may make the other terminal 11A into the same shape. In this embodiment, the terminal 11B has a wide shape, and the recessed region 16B is formed long. The recessed area is formed by cutting, pressing, or the like as in the first embodiment.

  FIG. 8 shows an example of a shunt-type current detection device in which the shunt resistor 3 is connected to the bus bar 20B. Also in this example, the wiring member (bus bar) 20B made of a conductive metal material is fitted into the recessed region 16B, and positioned on both sides of the wiring member 20B by the side wall 17 formed along the longitudinal direction of the region 16B. The bolt 21 and the nut (not shown) are fastened.

  In this example, the terminal 11B has a wide shape, and the recessed region 16B is formed long. Therefore, in assembling the bus bar 20B to the terminal 11B, the bus bar 20B can be more suitably positioned with respect to the bolt 21. And since the terminal 11B is wide, heat dissipation is also favorable.

  FIG. 9 shows a shunt resistor according to Example 4 of the present invention. The shunt resistor 4 is similar to the third embodiment in that the shunt resistor 4 is an example in which a region 16B that is recessed so as to be substantially orthogonal to the arrangement direction of the terminals 11A and 11B with respect to the resistor 12 is formed. However, the third embodiment is different in that the side wall 17 is on both sides of the recessed region 16B, whereas the fourth embodiment is only on one side of the recessed region 16B. Further, the fourth embodiment is different in that a recessed region 16B is formed by bending the terminal 11B. In Example 3 and Example 4, the direction of the recess 16 or the side wall 17 is set to be substantially perpendicular to the arrangement direction of the terminals 11A and 11B, but this angle may be arbitrarily changed. The side wall 17 can fix the mounting angle between the shunt resistor and the bus bar at a predetermined angle.

  FIG. 10 shows an example of a shunt-type current detection device in which the shunt resistor 4 is connected to the bus bar 20B. In this example, a wiring member (bus bar) 20B made of a conductive metal material is fitted to one side wall 17 and the bottom surface of the recessed region 16B and fixed by tightening a bolt 21 and a nut (not shown). . Also in this example, the bus bar 20 can be fixed to the terminal 11 </ b> B without causing a positional shift due to the tightening rotational force with only one side wall 17 with respect to the rotation of the bolt 21.

  FIG. 11 shows a configuration example of the shunt resistor according to the fifth embodiment of the present invention and the corresponding bus bar tip. The shunt resistor 5 includes a sawtooth uneven portion 19 around the hole 15A at the end of the terminal 11A, and also has a sawtooth uneven portion 19 around the hole 15B at the end of the terminal 11B. . Then, on the bus bar 20A side, a sawtooth uneven portion 19x that fits into the sawtooth uneven portion 19x is formed, and on the bus bar 20B side, a sawtooth uneven portion 19x that fits into the sawtooth uneven portion 19 is formed. doing. The serrated irregularities 19 and 19x are formed by cutting or pressing.

  FIG. 12 shows an example of a shunt-type current detection device in which the shunt resistor 5 is connected to the bus bar 20B. In this example, the serrated irregularities 19x of the wiring members 20A and 20B are respectively fitted to the serrated irregularities 19 of the terminals 11A and 11B (see FIG. 13), and tightened with bolts 21 and nuts 22 (not shown). Fix it.

  In the fifth embodiment, the serrated convex portion of the serrated uneven portion 19 corresponds to the side wall disclosed in the other embodiments, and corresponds to a region where the bottom portion between the convex portion and the convex portion is recessed. Therefore, the bus bars 20A and 20B can be fixed to the terminals 11A and 11B without causing a positional shift by the tightening rotational force of the bolt 21. Thus, the current can be measured with high accuracy and high reliability, as in the other embodiments.

  FIG. 14 shows a configuration example of the shunt resistor according to the sixth embodiment of the present invention and the corresponding bus bar tip. The terminals 11A and 11B of the shunt resistor 6 are provided with serrated irregularities 19 on the entire surface. Other configurations are the same as those of the shunt resistor of the fifth embodiment. The bus bars 20 </ b> A and 20 </ b> B are also provided with serrated irregularities 19 x that fit into the serrated irregularities 19. Also in Example 6, the serrated convex part of the serrated uneven part 19 corresponds to the side wall disclosed in the other examples, and corresponds to a region where the bottom part between the convex part and the convex part is recessed. The region is formed along the longitudinal direction of the terminals 11A and 11B, and a convex portion 19 (side wall) is formed along the longitudinal direction of the region.

  FIG. 15 shows an example of a shunt-type current detection device in which the shunt resistor 6 is connected to the bus bars 20A and 20B. Also in this example, the serrated irregularities 19x of the wiring members 20A and 20B are fitted into the serrated irregularities 19 of the terminals 11A and 11B (see FIG. 16), and tightened with bolts 21 and nuts 22 (not shown). Fix it.

  In the sixth embodiment, the terminals 11A and 11B provided with the serrated irregularities 19 are formed by the deformed wire drawing technique as in the second embodiment. In this example, as shown in FIG. 16, the concave and convex portions 19 and 19x mesh with each other over the entire surface of the terminal 11A and the entire surface of the bus bar 20A. Therefore, the bus bars 20A and 20B can be fixed to the terminals 11A and 11B without causing a positional shift by the tightening rotational force of the bolt 21. Further, even if the overlapping portions of the terminals 11A and 11B and the bus bars 20A and 20B are lengthened, no positional deviation occurs.

  Although the embodiments of the present invention have been described so far, it is needless to say that the present invention is not limited to the above-described embodiments and may be implemented in various forms within the scope of the technical idea.

The present invention can be suitably used for a current detection device using a shunt resistor that measures current with high accuracy and high reliability.

Claims (4)

A plate-like terminal made of a conductive metal material, a metal material having a smaller temperature coefficient of resistance than the terminal, and a resistor fixed to the terminal,
The terminal has a hole penetrating in the thickness direction of the terminal, and is provided with a region formed around the hole and recessed in the thickness direction of the terminal, and at least one side wall is provided along the longitudinal direction of the region. A shunt resistor provided.   The shunt resistor according to claim 1, wherein the recessed region is formed over the entire length of the terminal.   The shunt resistor according to claim 1, wherein the recessed region has an open portion at an end of the terminal. A pair of terminals made of a conductive metal material, a resistor made of a metal material having a resistance temperature coefficient smaller than that of the terminal, fixed to the terminal, and the terminal having a hole penetrating in the thickness direction. And a shunt resistor provided around the hole and provided with a region recessed in the thickness direction of the terminal, and having a side wall on at least one side along the longitudinal direction of the region;
A wiring member made of a conductive metal material,
The shunt-type current detection device, wherein the wiring member is formed around the hole and is fitted and fixed in a region recessed in the thickness direction of the terminal.

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