JP2019161225A - Shunt structure, current detection device, method of manufacturing the same, and method of mounting the same - Google Patents

Abstract

To provide a shunt structure capable of suppressing electrode corrosion caused by contact with a different metal.SOLUTION: The shunt structure includes: a shunt resistor 16; and a first bus bar 15 and a second bus bar 18 connected to both ends of the shunt resistor 16, respectively. The first bus bar 15 and the second bus bar 18 are made of pure aluminum or an aluminum alloy.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a shunt structure, a current detection device, a method for manufacturing the current detection device, and a method for mounting the current detection device.

Conventionally, a shunt structure in which a first bus bar and a second bus bar are connected to both ends of a shunt resistor has been proposed (see, for example, Patent Document 1). In the shunt structure described in Patent Document 1, a copper alloy is used as a material for the shunt resistor and the first bus bar and the second bus bar.
In recent years, from the viewpoint of weight reduction and cost reduction, bus bars made of aluminum alloy are becoming popular as other bus bars to which the first bus bar and the second bus bar of the shunt structure are connected.

JP, 2006-217829, A

However, in the shunt structure described in Patent Document 1, when the bus bar of the shunt structure is connected to another bus bar made of an aluminum alloy, there is a possibility that electric corrosion due to contact with different metals occurs. Therefore, the detection accuracy of the current value is lowered, and the reliability of the detection result may be lowered.
The present invention focuses on the above-described problems, and provides a shunt structure, a current detection device, a method for manufacturing the current detection device, and a method for mounting the current detection device that can prevent electrode corrosion due to contact with different metals. With the goal.

  In order to solve the above problems, an aspect of the present invention includes (a) a shunt resistor, (b) a first bus bar and a second bus bar connected to both ends of the shunt resistor, and (c) a first bus bar. The gist of the first bus bar and the second bus bar is a shunt structure made of pure aluminum or an aluminum alloy.

  In another aspect of the present invention, (a) a shunt resistor, a first bus bar and a second bus bar connected to both ends of the shunt resistor, a first electrode terminal connected to the first bus bar or the shunt resistor, and a second bus bar, respectively. A shunt structure having a second electrode terminal connected to the bus bar or the shunt resistor; and (b) a detection circuit connected to the first electrode terminal and the second electrode terminal and detecting the magnitude of the current flowing through the shunt resistor. (C) a shunt structure and a housing that houses the detection circuit, and (d) the first bus bar and the second bus bar are current detection devices made of pure aluminum or aluminum alloy.

  In another aspect of the present invention, (a) a shunt resistor and a shunt structure having a first bus bar and a second bus bar made of pure aluminum or an aluminum alloy connected to both ends of the shunt resistor are provided. Coating the periphery of the first connection portion with one bus bar and the periphery of the second connection portion between the shunt resistor and the second bus bar with an insulating resin; and (b) connecting the first electrode terminal to the first bus bar or the shunt resistor. And connecting the second electrode terminal to the second bus bar or the shunt resistor, and (c) a detection circuit for detecting the magnitude of the current flowing through the shunt resistor in each of the first electrode terminal and the second electrode terminal. The present invention is summarized as a method for manufacturing a current detecting device including connecting the two.

  According to another aspect of the present invention, there is provided (a) a mounting method of the above-described current detection device, wherein (b) the first bus bar and the second bus bar are brought into surface contact with another bus bar made of an aluminum alloy and welded or bolted. The gist of the present invention is the method of mounting the current detection device including the following.

  According to the present invention, even if the first bus bar and the second bus bar of the shunt structure are connected to another bus bar made of an aluminum alloy, only the same kind of metal contacts. Therefore, it is possible to provide a shunt structure, a current detection device, a manufacturing method of the current detection device, and a mounting method of the current detection device that can prevent electric corrosion due to contact with different metals.

It is a perspective view which shows the shunt structure which concerns on embodiment of this invention. It is sectional drawing which shows the internal structure of a current detection apparatus. It is a perspective view which shows the external appearance of an electric current detection apparatus. It is a top view which shows a 1st electrode terminal cover and a 2nd electrode terminal cover. It is a figure which shows the connection state of shunt resistance and a bus bar, (a) is a sectional side view which shows the connection state which piled up edge parts up and down, (b) is the connection state which faced end surfaces. It is a sectional side view shown. It is side sectional drawing which shows a plating layer. It is sectional drawing which shows the manufacturing method of an electric current detection apparatus. It is sectional drawing which shows the manufacturing method of an electric current detection apparatus. It is sectional drawing which shows the manufacturing method of an electric current detection apparatus. It is a perspective view which shows the shunt structure which concerns on a modification. It is a perspective view which shows the shunt structure which concerns on a modification. It is a top view which expands and shows the principal part of the shunt structure which concerns on a modification. It is a sectional side view which expands and shows the principal part of the shunt structure which concerns on a modification. It is a sectional side view which shows the barrier layer which concerns on a modification.

Hereinafter, a shunt structure, a current detection device, a current detection device manufacturing method, and a current detection device mounting method according to embodiments of the present invention will be described with reference to the drawings.
The following embodiments exemplify methods and apparatuses for embodying the technical idea of the present invention, and the technical idea of the present invention includes the shape, structure, arrangement, etc. of the component parts. It is not specified to the following. The technical idea of the present invention can be variously modified within the technical scope defined by the claims described in the claims.

As shown in FIG. 1, the shunt structure 3 according to the embodiment of the present invention includes a shunt resistor 16 and a first bus bar 15 and a second bus bar 18 connected to both ends of the shunt resistor 16. The first bus bar 15 and the second bus bar 18 are made of pure aluminum or aluminum alloy.
Further, the first connection portion 17 between the shunt resistor 16 and the first bus bar 15 and the second connection portion 19 between the shunt resistor 16 and the second bus bar 18 are each configured by brazing connection.
In other words, the first connection part 17 between the shunt resistor 16 and the first bus bar 15 and the second connection part 19 between the shunt resistor 16 and the second bus bar 18 are brazed.

Furthermore, in the shunt structure 3 according to the embodiment of the present invention, as shown in FIGS. 6 and 14, the brazing 41 constituting the brazing connection contains tin and is connected to the shunt resistor 16 of the first bus bar 15. It is preferable to have a plating layer 42 containing tin on the connection surface and the connection surface with the shunt resistor 16 of the second bus bar 18. At that time, it is more preferable that the shunt resistor 16 is made of a copper alloy containing tin.
In the shunt structure 3 according to the embodiment of the present invention, the connection surface of the first bus bar 15 with the shunt resistor 16, the connection surface of the second bus bar 18 with the shunt resistor 16, and the first bus bar 15 of the shunt resistor 16 It is preferable to provide barrier layers 45, 46, and 47 for suppressing diffusion of tin included in the solder 41 on the connection surface of the shunt resistor 16 and the connection surface of the shunt resistor 16 with the second bus bar 18.

  Further, in the shunt structure 3 according to the embodiment of the present invention, the first connecting portion 17 is configured such that the end portions of the shunt resistor 16 and the first bus bar 15 overlap each other as shown in FIG. It is preferable that the second connection portion 19 is configured by brazing connection in which end portions of the shunt resistor 16 and the second bus bar 18 are vertically overlapped. Further, as shown in FIG. 5 (b), the first connection portion 17 is configured by brazing connection in which the end surfaces of the shunt resistor 16 and the first bus bar 15 are butted together, and the second connection portion 19 is configured by the shunt resistor 16. It is also preferable to be configured by brazing connection in which end faces of the second bus bar 18 are abutted with each other.

  Further, in the shunt structure 3 according to the embodiment of the present invention, as shown in FIG. 2, the periphery of the first connection portion 17 between the shunt resistor 16 and the first bus bar 15, and the shunt resistor 16 and the second bus bar 18. It is preferable that the periphery of the second connection portion 19 is coated with an insulating resin or a metal. Furthermore, as shown in FIGS. 12 and 13, the width of the first bus bar 15 and the width of the second bus bar 18 are preferably larger than the width of the shunt resistor 16. Further, the thickness of the first bus bar 15 and the thickness of the second bus bar 18 are preferably larger than the thickness of the shunt resistor 16.

  On the other hand, as illustrated in FIG. 2, the current detection device 1 according to the embodiment of the present invention includes a shunt resistor 16, a first bus bar 15 and a second bus bar 18 connected to both ends of the shunt resistor 16, and a first bus bar. The shunt structure 3 having the first electrode terminal 11 connected to 15 and the second electrode terminal 13 connected to the second bus bar 18 is provided. Also, a detection circuit 4 connected to the first electrode terminal 11 and the second electrode terminal 13 and detecting the magnitude of the current flowing through the shunt resistor 16, and a housing 2 housing the shunt structure 3 and the detection circuit 4 Is provided. The first bus bar 15 and the second bus bar 18 are made of pure aluminum or aluminum alloy.

Further, in the current detection device 1 according to the embodiment of the present invention, the current detection device 1 includes the periphery of the first connection portion 17 between the shunt resistor 16 and the first bus bar 15 and the first connection between the shunt resistor 16 and the second bus bar 18. It is preferable that the periphery of the two connection portions 19 is coated with an insulating resin or metal. 2 shows an example in which the first electrode terminal 11 is connected to the first bus bar 15 and the second electrode terminal 13 is connected to the second bus bar 18, but for example, as shown in FIG. Both the first electrode terminal 11 and the second electrode terminal 13 may be connected to the shunt resistor 16.
Further, in the current detection device 1 according to the embodiment of the present invention, the insulating resin coating the periphery of the first connection portion 17 and the periphery of the second connection portion 19 is integrated with the insulating resin constituting the housing 2. Preferably there is.
Furthermore, the current detection device 1 according to the embodiment of the present invention includes a periphery of the third connection portion 35 between the first bus bar 15 and the first electrode terminal 11 and a fourth connection between the second bus bar 18 and the second electrode terminal 13. It is preferable that the periphery of the connection portion 37 is coated with an insulating resin or a metal.

Further, in the current detection device 1 according to the embodiment of the present invention, the housing 2 includes a lower space 7 for accommodating the shunt structure 3, an upper space 8 for accommodating the detection circuit 4, and the lower space 7. It has an internal partition wall 9 that partitions the upper space 8, and the internal partition wall 9 has a first through hole 12 and a second through hole 14 through which the first electrode terminal 11 and the second electrode terminal 13 pass, and the first electrode The terminal 11 and the second electrode terminal 13 are separated from the inner peripheral surfaces of the first through hole 12 and the second through hole 14, and the periphery of the third connection part 35 and the periphery of the fourth connection part 37 are coated. The insulating resin is preferably an insulating resin different from the insulating resin constituting the housing 2. More specifically, the insulating resin coating the periphery of the third connection portion 35 and the periphery of the fourth connection portion 37 may be an insulating resin having a lower elastic modulus than the insulating resin constituting the housing 2. preferable.
In the current detection device 1 according to the embodiment of the present invention, the first bus bar 15 and the second bus bar 18 are welded or bolted in surface contact with the other bus bars 20 and 24 made of an aluminum alloy. preferable.

  The manufacturing method of the current detection device 1 according to the embodiment of the present invention includes a shunt resistor 16 and a first bus bar 15 and a second bus bar 18 made of pure aluminum or aluminum alloy connected to both ends of the shunt resistor 16. Coating the shunt structure 3 with an insulating resin around the first connection portion 17 between the shunt resistor 16 and the first bus bar 15 and around the second connection portion 19 between the shunt resistor 16 and the second bus bar 18; The first electrode terminal 11 is connected to the first bus bar 15 or the shunt resistor 16, and the second electrode terminal 13 is connected to the second bus bar 18 or the shunt resistor 16, and the first electrode terminal 11 and the second electrode terminal 13 includes connecting a detection circuit 4 for detecting the magnitude of the current flowing through the shunt resistor 16.

Further, in the method for manufacturing the current detection device 1 according to the embodiment of the present invention, the casing 2 of the current detection device 1 is formed by coating the periphery of the first connection portion 17 and the periphery of the second connection portion 19 with an insulating resin. It is preferable that the housing 2 is formed integrally with the shunt structure 3 so that a part of the cover (cover 26) is in close contact with the shunt structure 3 and covers the periphery of the first connection portion 17 and the second connection portion 19.
Furthermore, the method for manufacturing the current detection device 1 according to the embodiment of the present invention connects the first electrode terminal 11 to the first bus bar 15 in connecting the first electrode terminal 11 and the second electrode terminal 13, and The second electrode terminal 13 is connected to the second bus bar 18, the fourth connection between the second bus bar 18 and the second electrode terminal 13, and the periphery of the third connection portion 35 between the first bus bar 15 and the first electrode terminal 11. It is preferable to coat the periphery of the portion 37 with an insulating resin.
Further, in the method for manufacturing the current detection device 1 according to the embodiment of the present invention, when the periphery of the first connection portion 17 and the periphery of the second connection portion 19 are coated with the insulating resin, the third connection is performed with the insulating resin. It is preferable that coating around the portion 35 and around the fourth connection portion 37 is performed at the same time.

  Furthermore, in the method for manufacturing the current detection device 1 according to the embodiment of the present invention, the shunt structure 3 is accommodated by coating the periphery of the first connection portion 17 and the periphery of the second connection portion 19 with an insulating resin. A first through hole 12 for partitioning the lower space 7, the upper space 8 for accommodating the detection circuit 4, the lower space 7 and the upper space 8, and allowing the first electrode terminal 11 and the second electrode terminal 13 to pass through. A resin molded body made of an insulating resin having an internal partition wall 9 in which the second through-hole 14 is formed is formed as the housing 2, and the first electrode terminal 11 and the second electrode terminal 13 are connected to each other. The terminal 11 is separated from the inner peripheral surfaces of the first through hole 12 and the second through hole 14, and the second electrode terminal 13 is separated from the inner peripheral surfaces of the first through hole 12 and the second through hole 14. Contact between the first electrode terminal 11 and the second electrode terminal 13 In determining the position and coating the periphery of the third connecting portion 35 and the fourth connecting portion 37 with an insulating resin, the third connecting portion 35 and the fourth connecting portion are made of an insulating resin different from the insulating resin constituting the housing 2. It is preferred to perform a coating around 37.

In addition, although the example which coats the circumference | surroundings of the 3rd connection part 35 and the circumference | surroundings of the 4th connection part 37 with insulating resin different from the insulation resin which comprises the housing | casing 2 was shown, for example, the circumference | surroundings of the 1st connection part 17 When the periphery of the second connection portion 19 is coated with an insulating resin, the periphery of the third connection portion 35 and the periphery of the fourth connection portion 37 may be coated with the insulating resin.
In addition, in the method for manufacturing the current detection device 1 according to the embodiment of the present invention, the insulating resin that coats the periphery of the third connecting portion 35 and the periphery of the fourth connecting portion 37 is more than the insulating resin that constitutes the housing 2. Is preferably an insulating resin having a low elastic modulus.
The mounting method of the current detection device 1 according to the embodiment of the present invention includes bringing the first bus bar 15 and the second bus bar 18 into surface contact with other bus bars 20 and 24 made of an aluminum alloy, and welding or bolting. It is out.

(Construction)
Next, the current detection device 1 according to the embodiment of the present invention will be described in more detail.
As shown in FIG. 3, the current detection device 1 according to the embodiment of the present invention includes a box-shaped housing 2, a narrow plate-shaped shunt structure 3, and a plate-shaped housing 2 as illustrated in FIG. 2. And a detection circuit 4.

(Casing)
The housing 2 includes a box 5 formed in a box shape with an open upper surface, and a lid 6 that closes the opened upper surface of the box 5. Insulating resin is used as the material of the box 5 and the lid 6. In the box 5, as shown in FIG. 2, a space in the box 5 is accommodated in a lower space 7 (“first space” in a broad sense) that houses the shunt structure 3 and a detection circuit 4. An internal partition wall 9 that is divided into two spaces, an upper space 8 (in a broad sense, “second space”), is provided integrally with the box 5.

  In order to accommodate the shunt structure 3, the lower space 7 has an opening 10 on one side surface in the longitudinal direction of the box 5 and has a concave shape extending in the other side surface direction. The cross-sectional shape of the lower space 7 is a slit shape that is narrow in the vertical direction and wide in the horizontal direction. The length from the opening 10 of the lower space 7 to the concave bottom surface is a length that can accommodate the first bus bar 15, the shunt resistor 16, and a part of the second bus bar 18. That is, the end of the second bus bar 18 protrudes from the opening 10 in a state where the shunt structure 3 is accommodated in the lower space 7. The upper space 8 has a box shape with an upper surface opened so that the detection circuit 4 can be accommodated.

  As shown in FIG. 4, the inner partition wall 9 has a first through hole 12 through which the first electrode terminal 11 of the housed shunt structure 3 passes and a second through hole through which the second electrode terminal 13 of the shunt structure 3 passes. A hole 14 is formed. The first electrode terminal 11 and the second electrode terminal 13 are electrode terminals for connecting the shunt structure 3 and the detection circuit 4. The cross-sectional shape of the first through-hole 12 is such that the inner peripheral surface of the first through-hole 12 is not in contact with the first electrode terminal 11 and the internal partition wall 9 is the first connection portion between the first bus bar 15 and the shunt resistor 16. A portion overlapping with the first connection portion 17 is formed in a circular shape so as to cover the periphery of the portion 17. The cross-sectional shape of the second through hole 14 is such that the inner peripheral surface of the second through hole 14 is not in contact with the second electrode terminal 13, and the internal partition wall 9 is the second connection portion between the second bus bar 18 and the shunt resistor 16. A portion overlapping the second connecting portion 19 is formed in a circular shape so as to cover the periphery of the portion 19.

  Further, as shown in FIG. 5, an opening is provided on one side surface in the short direction of the box 5 below the lower space 7 of the box 5 in order to accommodate the battery post terminal 20. A recess 21 extending in the other side surface direction is provided. The battery post terminal 20 is an electrode terminal connected to the battery post of the on-vehicle battery of the electric vehicle. A battery mounted on an electric vehicle generally generates a high voltage such as 48 [V] and a large current such as 1 [A]. As a material of the battery post terminal 20, an aluminum alloy is used from the viewpoint of weight reduction and cost reduction. The cross-sectional shape of the recess 21 is a slit shape that is narrow in the vertical direction and wide in the left-right direction. Further, the recess 21 is connected to the lower space 7 so that the battery post terminal 20 and the first bus bar 15 are connected.

  A cylindrical connector 22 is formed on the side surface of the box 5 in the longitudinal direction on the side surface opposite to the side surface on which the opening 10 is provided. An output terminal 23 extending from the upper space 8 is provided inside the connector 22. The output terminal 23 is a terminal for connecting the detection circuit 4 and an external device. An example of the external device is a computer such as an ECU (engine control unit). A copper alloy is used as the material of the output terminal 23.

(Shunt structure)
As shown in FIG. 1, the shunt structure 3 includes a shunt resistor 16 and a first bus bar 15 and a second bus bar 18 connected to both ends of the shunt resistor 16. The entire shunt structure 3 is elongated in the direction in which the first bus bar 15, the shunt resistor 16 and the plate-like second bus bar 18 are arranged. As shown in FIG. 2, the shunt structure 3 includes a first bus bar 15, a shunt resistor 16, and a second bus bar 18 in the lower space 7 so that the end of the second bus bar 18 protrudes from the opening 10 of the lower space 7. Part of the house. The accommodated first bus bar 15 is connected to a battery post terminal 20 (hereinafter also referred to as “another bus bar 20”). The protruding second bus bar 18 is connected to another bus bar 24 connected to a ground line or the like (not shown) when the current detection device 1 is mounted on the vehicle. As the material of the other bus bar 24, an aluminum alloy is used from the viewpoint of weight reduction and cost reduction as with the other bus bar 20.

  As a material of the shunt resistor 16, a copper alloy containing copper (Cu), manganese (Mn), tin (Sn), or the like is used. The first bus bar 15 and the second bus bar 18 are made of pure aluminum or aluminum alloy. By using pure aluminum or an aluminum alloy, even if the first bus bar 15 and the second bus bar 18 are connected to other bus bars 20 and 24 made of an aluminum alloy, only the same kind of metal comes into contact. It is possible to prevent electrical corrosion due to. Various aluminum alloys such as 1000 series and 3000 series can be adopted as the aluminum alloy.

  As shown in FIG. 5A, for example, the first connection part 17 between the shunt resistor 16 and the first bus bar 15 and the second connection part 19 between the shunt resistor 16 and the second bus bar 18 are connected to each other. A method of configuring by welding connection or brazing connection in which the end surfaces are brought into surface contact with each other, as shown in FIG. 5B, a method of configuring by welding connection or brazing connection in which the end surfaces are butted together. Can be adopted. FIGS. 5A and 5B show a method of configuring by brazing connection as an example. Brazing connection means melting a solder 41 having a melting point lower than that of a member to be connected (shunt resistor 16, first bus bar 15, second bus bar 18) and using it as an adhesive without melting the member. It is configured to be connected by “brazing” for connecting members. As the wax 41, for example, one containing tin (Sn) or one containing tin (Sn) and zinc (Zn) is preferable. When using the solder 41 containing tin or the solder 41 containing tin and zinc, as shown in FIG. 6, the connection surface with the shunt resistor 16 of the first bus bar 15 and the shunt of the second bus bar 18. It is preferable to provide a plating layer 42 containing tin on the connection surface with the resistor. By providing the plating layer 42, the brazing 41 is easily adapted to the first bus bar 15 and the second bus bar 18, and the brazing connection can be easily realized.

The connection surface of the first bus bar 15 and the connection surface of the second bus bar 18 include the upper surface or the lower surface of the end portion that comes into contact with the shunt resistor 16 when the end portions overlap each other and make surface contact. When the end faces are abutted with each other, an end face that comes into contact with the shunt resistor 16 is exemplified.
The plating layer 42 is formed by laminating a base layer 43 and an outermost layer 44 in this order on the surfaces of the first bus bar 15 and the second bus bar 18. Examples of the material of the base layer 43 include nickel (Ni), tin (Sn), chromium (Cr), zinc (Zn), titanium (Ti), manganese (Mn), tungsten (W), tantalum (Ta), An alloy or compound containing one or more of molybdenum (Mo) and niobium (Nb) can be used. As a material of the outermost layer 44, for example, tin can be used. The thickness of the plating layer 42 is preferably, for example, 100 nm or more and 10 μm or less.

Here, as a method for detecting the presence or absence of the plated layer 42, for example, a concentration gradient of tin content between the brazed shunt resistor 16 and the bus bar (first bus bar 15 and second bus bar 18) is used. A method of detecting and detecting based on the detected concentration gradient or the like can be employed.
Further, when using the solder 41 containing tin, it is preferable to use a copper alloy containing tin as the material of the shunt resistor 16. For example, a material containing about 90% by mass of copper (Cu), about 6-8% by mass of manganese (Mn), and about 2-3% by mass of tin (Sn) with respect to the total mass of the shunt resistor 16 is used. By using a copper alloy containing tin as the material of the shunt resistor 16, the solder 41 can be easily adapted to the shunt resistor 16, and brazing can be easily performed.

Further, unlike the method of connecting the shunt resistor 16 and the bus bar (first bus bar 15 and second bus bar 18) by brazing, the shunt resistor 16 and the bus bar (first bus bar 15 and second bus bar 18) are connected. 18) does not need to be alloyed at the connecting portion, and does not produce a weld heat affected zone (HAZ), so that the high-quality shunt structure 3 can be stably formed.
Examples of the welding method include electron beam welding and laser beam welding. Further, when the shunt resistor 16, the first bus bar 15 and the second bus bar 18 are connected by welding, a copper alloy containing tin is used as the material of the shunt resistor 16, so that copper containing no tin is used. Compared to the case where an alloy is used, the area of the weld heat affected zone (HAZ) can be reduced.

Moreover, as a connection method between the first bus bar 15 and the other bus bar 20 and a connection method between the second bus bar 18 and the other bus bar 24, for example, the end surfaces are abutted with each other or the end portions are overlapped with each other. Then, a method is used in which the end portions are brought into surface contact and welded. Unlike the method of fastening bolts by bringing the ends into surface contact and welding, the force for fastening the first bus bar 15, the second bus bar 18, and the other bus bars 20, 24, that is, a pure aluminum or aluminum alloy bus bar. Does not occur. Therefore, it is possible to prevent damage to the bus bar made of pure aluminum or aluminum alloy.
In the present embodiment, as a method for connecting the first bus bar 15 and the other bus bar 20 and a method for connecting the second bus bar 18 and the other bus bar 24, a method of welding the end portions in surface contact is used. Although an example is shown, other configurations may be employed. For example, it is possible to use a method in which the ends are overlapped with each other and bolted together. According to the method in which the ends are overlapped with each other and bolted, unlike the welding method, no special equipment for welding is required, and the labor required for connection can be reduced.

  Further, as shown in FIG. 2, the surfaces of the first connection portion 17 and the second connection portion 19 have a partition wall remaining portion 25 between the first through hole 12 and the second through hole 14 in the internal partition wall 9, and The box 5 is covered and covered with the bottom and side surfaces. That is, the remaining partition wall 25 and the bottom and side surfaces of the box 5 form an insulating resin cover 26 that covers the periphery of the first connection portion 17 and the second connection portion 19. In the cover 26, as shown in a method for manufacturing the current detection device 1 described later, the periphery of the first connection portion 17 and the second connection portion 19 is coated with an insulating resin. By covering the periphery of the first connection portion 17 and the second connection portion 19 with the cover 26, water generated by condensation or the like is prevented from coming into contact with the periphery of the first connection portion 17 and the second connection portion 19. it can. Therefore, even if different metals such as an aluminum alloy and a copper alloy come into contact with each other at the first connection portion 17 and the second connection portion 19, since ionization by water is prevented, it is possible to suppress electric corrosion due to the contact with different metals. ing.

In the first region 27 facing the first through hole 12 on the upper surface of the first bus bar 15, as shown in FIG. 4, two linear portions 28 of the U-shaped first electrode terminal 11 that are parallel to each other. 29 are directed upward and the bottom surface of the intermediate portion 30 of the U-shaped first electrode terminal 11 is connected. The first electrode terminal 11 is separated from the inner peripheral surface of the first through hole 12, and is connected to a position where the first electrode terminal 11 does not contact the inner peripheral surface of the first through hole 12. In addition, in the second region 31 facing the second through hole 14 on the upper surface of the second bus bar 18, the two straight portions 32 and 33 parallel to each other of the U-shaped second electrode terminal 13 are upward. The bottom surface of the intermediate part 34 of the U-shaped second electrode terminal 13 is connected. The second electrode terminal 13 is separated from the inner peripheral surface of the second through hole 14, and is connected to a position where the second electrode terminal 13 is not in contact with the inner peripheral surface of the second through hole 14. Thereby, even if the shunt structure 3 and the housing 2 are relatively moved by an external force or the like, a direct collision between the inner peripheral surface of the first through-hole 12 and the first electrode terminal 11, A direct collision between the peripheral surface and the second electrode terminal 13 can be prevented. And damage to the first electrode terminal 11 and the second electrode terminal 13 can be suppressed.
As a method for connecting the first electrode terminal 11 and the first bus bar 15 and a method for connecting the second electrode terminal 13 and the second bus bar 18, for example, a method of superimposing them vertically and welding them can be adopted.

  In addition, the first region 27 on the upper surface of the first bus bar 15 has a first terminal made of insulating resin so as to closely cover the periphery of the third connection portion 35 between the first bus bar 15 and the first electrode terminal 11. A cover 36 is formed. Further, a second terminal cover made of insulating resin is provided in the second region 31 on the upper surface of the second bus bar 18 so as to closely cover the periphery of the fourth connecting portion 37 between the second bus bar 18 and the second electrode terminal 13. 38 is formed. As a method of forming the first terminal cover 36 and the second terminal cover 38, a method of coating the periphery of the third connection portion 35 and the fourth connection portion 37 with an insulating resin is used. By coating the periphery of the third connection part 35 and the fourth connection part 37 with the first terminal cover 36 and the second terminal cover 38, water generated by dew condensation or the like is generated around the third connection part 35 and the fourth connection part. 37 can be prevented from contacting the periphery. Therefore, even if different metals such as aluminum alloy and copper alloy contact with each other at the third connection portion 35 and the fourth connection portion 37, ionization by water is prevented, so that electric corrosion due to contact with different metals can be suppressed. It has become.

  As the insulating resin of the first terminal cover 36 and the second terminal cover 38, that is, the insulating resin coating the periphery of the third connecting portion 35 and the periphery of the fourth connecting portion 37, the insulating resin constituting the box 5 Different insulating resins are used. In particular, as the insulating resin coating the periphery of the third connecting portion 35 and the periphery of the fourth connecting portion 37, a resin having a lower elastic modulus (softer) than the insulating resin constituting the cover 26 is preferable. By using an insulating resin having a low elastic modulus, the shunt structure 3 and the housing 2 move relative to each other, the first terminal cover 36 is pushed on the inner peripheral surface of the first through hole 12, and the second through hole 14 Even if the second electrode terminal 13 is pressed on the inner peripheral surface, the pressing force can be absorbed by the first terminal cover 36 and the second terminal cover 38. The transmission of force from the first terminal cover 36 to the first electrode terminal 11 and the transmission of force from the second terminal cover 38 to the second electrode terminal 13 can be suppressed, and the first electrode terminal 11 and the second electrode terminal can be suppressed. 13 can be prevented from being damaged.

(Detection circuit)
As shown in FIG. 2, the detection circuit 4 is accommodated in the upper space 8 with one surface facing upward and the other surface facing downward, and the first electrode terminal 11 and the second electrode terminal of the shunt structure 3. 13 and the output terminal 23 of the connector 22. Then, the detection circuit 4 performs pulse discharge through the first electrode terminal 11 and the second electrode terminal 13, and determines the magnitude of the current flowing through the shunt resistor 16 by the pulse discharge, and the like. Detection is performed via the terminal 13. The detection circuit 4 outputs the detection result to an external device via the output terminal 23.

(Production method)
Next, a manufacturing method of the current detection device 1 according to the embodiment of the present invention will be described.
First, the housing 2 is formed integrally with the shunt structure 3. As a method for forming the housing 2, for example, an insert molding method can be employed. In the insert molding method, first, the first bus bar 15 is brought into surface contact with the battery post terminal 20 and welded. Subsequently, the shunt structure 3, the battery post terminal 20, and the output terminal 23 are loaded into the molding die of the box 5. Subsequently, an insulating resin is injected into the molding die of the box 5, the injected insulating resin is cured, and the box 5 is attached to the shunt structure 3, the battery post terminal 20, and the output terminal 23 as shown in FIG. 7. Are integrally formed.

  That is, as a box 5, a resin molded body made of an insulating resin having a lower space 7, an upper space 8, and an internal partition wall 9, a shunt structure 3 is accommodated in the lower space 7, and a battery post terminal 20 is placed in the recess 21. The connector 22 is formed in a state where the output terminal 23 is accommodated in the connector 22. Thereby, a part of the housing 2 of the current detection device 1, that is, the partition wall remaining portion 25, the bottom surface and the side surface of the box 5 are in close contact with the shunt structure 3, and the first connection portion 17 and the second connection portion 19. The periphery of the first connection portion 17 and the second connection portion 19 is coated with an insulating resin so as to cover the periphery. Then, a cover 26 made of insulating resin is formed to cover the first connection portion 17 and the second connection portion 19 in close contact with each other.

  Subsequently, as shown in FIG. 8, the first electrode terminal 11 is connected to the first region 27 on the upper surface of the first bus bar 15. Similarly, the second electrode terminal 13 is connected to the second region 31 on the upper surface of the second bus bar 18. At that time, the first electrode terminal 11 and the inner peripheral surface of the first through hole 12 are separated from each other, and the second electrode terminal 13 and the inner peripheral surface of the second through hole 14 are separated from each other. And the connection position of the 2nd electrode terminal 13 is determined. As a connection method between the first bus bar 15 and the first electrode terminal 11 and a connection method between the second bus bar 18 and the second electrode terminal 13, a method of overlapping and welding can be employed.

  Subsequently, each of the periphery of the third connection portion 35 and the periphery of the fourth connection portion 37 is coated with an insulating resin, and the periphery of the third connection portion 35 and the fourth connection portion 37 is adhered and covered. A first terminal cover 36 and a second terminal cover 38 are formed. Specifically, first, a liquid insulating resin is filled in a space surrounded by the first region 27 on the upper surface of the first bus bar 15 and the inner peripheral surface of the first through hole 12. Subsequently, the filled insulating resin is cured, and the first terminal cover 36 is formed by coating the periphery of the third connection portion 35 as shown in FIG. Similarly, a liquid insulating resin is filled in a space surrounded by the second region 31 on the upper surface of the second bus bar 18 and the inner peripheral surface of the second through hole 14. Subsequently, the filled insulating resin is cured, and the periphery of the fourth connection portion 37 is coated, thereby forming the second terminal cover 38. As the insulating resin for forming the first terminal cover 36 and the second terminal cover 38, that is, the insulating resin that coats the periphery of the third connection portion 35 and the periphery of the fourth connection portion 37, the insulation constituting the housing 2 is used. An insulating resin different from the resin can be used. In particular, an insulating resin having a lower elastic modulus than the insulating resin constituting the cover 26 is suitable.

Subsequently, as shown in FIG. 2, the detection circuit 4 is accommodated in the upper space 8 of the box 5, and the first electrode terminal 11, the second electrode terminal 13, and the output terminal 23 are connected to the accommodated detection circuit 4. . Subsequently, the opened upper surface of the box 5 is closed with the lid 6. Thereby, the electric current detection apparatus 1 is formed.
After forming the current detection device 1, the second bus bar 18 of the shunt structure 3 is brought into surface contact with another bus bar 24 connected to a ground line or the like and welded. Further, the output terminal 23 is connected to an external device such as an ECU. Thereby, the electric current detection apparatus 1 is mounted in an electric vehicle.
In addition, as a connection method between the second bus bar 18 and the other bus bar 24, a bolt fastening method may be used. The connection method between the first bus bar 15 and the other bus bars 20 is also the same.

As described above, in the shunt structure 3 and the current detection device 1 according to the embodiment of the present invention, the first bus bar 15 and the second bus bar 18 are made of pure aluminum or an aluminum alloy. Therefore, even if the first bus bar 15 and the second bus bar 18 of the shunt structure 3 are connected to other bus bars 20 and 24 made of an aluminum alloy, only the same kind of metal comes into contact therewith. Therefore, it is possible to provide the shunt structure 3 and the current detection device 1 that can prevent the electric corrosion due to the contact with different metals.
The shunt resistor 16 and the first bus bar 15, and the shunt resistor 16 and the second bus bar 18 are connected by brazing. Therefore, for example, unlike the method in which the shunt resistor 16 and the bus bar (the first bus bar 15 and the second bus bar 18) are connected by welding, the shunt resistor 16 and the bus bar need not be alloyed at the connection portion, and welding is also possible. Since no heat affected zone (HAZ) is generated, the high-quality shunt structure 3 can be stably formed.

For example, when the shunt resistor 16 and the bus bar (the first bus bar 15 and the second bus bar 18) are connected by welding, the shunt resistor 16 and the bus bar are alloyed at the connection portion, Since the influence part (HAZ) is generated, the quality of the shunt structure 3 becomes unstable, and the quality variation between products increases. In addition, the aging stability of the resistance performance decreases.
Further, the solder 41 constituting the brazing connection contains tin, and a plating layer containing tin is formed on the connection surface of the first bus bar 15 with the shunt resistor 16 and the connection surface of the second bus bar 18 with the shunt resistor 16. 42. Therefore, the row 41 is easy to become familiar with the first bus bar 15 and the second bus bar 18, and the brazed connection can be easily realized.

  The shunt resistor 16 is made of a copper alloy containing tin. Therefore, the solder 41 can be easily adapted to the shunt resistor 16, and the brazing connection can be easily realized. Moreover, since tin is contained, the absolute value of the temperature coefficient (TCR) of the shunt structure 3 can be lowered, for example, ± 50 ppm or less. Furthermore, the volume resistivity (ρ) of the shunt structure 3 can be lowered, for example, 0.35 μΩ · m or less. Incidentally, for example, when a copper alloy containing copper, manganese, and nickel is used as the material of the shunt resistor 16, the volume resistivity (ρ) of the shunt structure 3 is large. 4 μΩ · m or more, and the volume of the shunt structure 3 is increased.

Further, the first connection portion 17 is configured by brazing connection in which the end portions of the shunt resistor 16 and the first bus bar 15 are vertically overlapped, and the second connection portion 19 is formed by the shunt resistor 16 and the second bus bar 18. It is assumed that it is configured by brazing connection in which the end portions of the two are vertically overlapped. Therefore, the first bus bar 15, the shunt resistor 16, and the second bus bar 18 can be formed in a single plate shape.
Further, the first connection portion 17 is configured by brazing connection in which end surfaces of the shunt resistor 16 and the first bus bar 15 are abutted, and the second connection portion 19 connects end surfaces of the shunt resistor 16 and the second bus bar 18 to each other. It was assumed to be composed of butted brazing connections. Therefore, the contact area between the first bus bar 15 and the shunt resistor 16 and the contact area between the second bus bar 18 and the shunt resistor 16 can be increased, and the shunt resistor 16, the first bus bar 15 and the second bus bar 18 can be firmly joined. .

Further, as shown in FIG. 2, the periphery of the first connection portion 17 between the shunt resistor 16 and the first bus bar 15 and the periphery of the second connection portion 19 between the shunt resistor 16 and the second bus bar 18 are coated with an insulating resin. It was set as the structure. Therefore, it is possible to prevent water generated by condensation or the like from coming into contact with the periphery of the first connection portion 17 and the second connection portion 19. Therefore, even if the dissimilar metals of the aluminum alloy and the copper alloy are in contact with each other around the first connecting part 17 and the second connecting part 19, ionization by water is prevented, and electric corrosion due to the dissimilar metal contact can be suppressed. .
Further, the insulating resin coating the periphery of the first connection portion 17 and the periphery of the second connection portion 19 is integrated with the insulating resin constituting the box 5 of the housing 2. Therefore, at the time of forming the box 5, coating can be performed together, and the labor required for coating can be reduced.

The periphery of the third connection portion 35 between the first bus bar 15 and the first electrode terminal 11 and the periphery of the fourth connection portion 37 between the second bus bar 18 and the second electrode terminal 13 are coated with an insulating resin. The configuration. Therefore, it is possible to prevent water generated by condensation or the like from coming into contact with the periphery of the third connection portion 35 and the fourth connection portion 37. Therefore, even if different metals of the aluminum alloy and the copper alloy are in contact with each of the third connection portion 35 and the fourth connection portion 37, ionization by water is prevented, so that electric corrosion due to the contact of different metals is suppressed. it can.
Further, the first electrode terminal 11 and the second electrode terminal 13 are separated from the inner peripheral surfaces of the first through hole 12 and the second through hole 14. Therefore, even if the shunt structure 3 and the housing 2 move relative to each other due to an external force or the like, a direct collision between the inner peripheral surface of the first through hole 12 and the first electrode terminal 11, A direct collision between the peripheral surface and the second electrode terminal 13 can be prevented. Therefore, damage to the first electrode terminal 11 and the second electrode terminal 13 can be suppressed.

In the above-described embodiment, an example of coating the periphery of the third connection portion 35 and the periphery of the fourth connection portion 37 after coating the periphery of the first connection portion 17 and the periphery of the second connection portion 19 is performed. Although shown, other methods can be employed. For example, when the periphery of the first connection portion 17 and the periphery of the second connection portion 19 are coated with an insulating resin, the periphery of the third connection portion 35 and the periphery of the fourth connection portion 37 are made of the insulating resin used for coating. Coating may also be performed, and the labor required for coating can be reduced.
The insulating resin coating the periphery of the third connecting portion 35 and the periphery of the fourth connecting portion 37 is an insulating resin having a lower elastic modulus than the insulating resin constituting the box 5. Therefore, the shunt structure 3 and the housing 2 move relative to each other by an external force, the first terminal cover 36 is pushed by the inner peripheral surface of the first through hole 12, and the first inner surface of the second through hole 14 Even if the two-electrode terminal 13 is pressed, the pressing force can be absorbed by the first terminal cover 36 and the second terminal cover 38. Therefore, transmission of force from the first terminal cover 36 to the first electrode terminal 11 and transmission of force from the second terminal cover 38 to the second electrode terminal 13 can be suppressed, and the first electrode terminal 11 and the second electrode terminal 13 can be suppressed. Damage can be prevented.

Furthermore, the first bus bar 15 and the second bus bar 18 are configured to be welded or bolted in surface contact with other bus bars 20 and 24 made of an aluminum alloy. Therefore, the first bus bar 15 and the second bus bar 18 and the other bus bars 20 and 24 can be more appropriately connected.
In the method for manufacturing the current detection device 1 according to the embodiment of the present invention, the cover 26 of the box 5 is in close contact with the shunt structure 3 so as to cover the periphery of the first connection portion 17 and the second connection portion 19. In addition, the box 5 is formed integrally with the shunt structure 3. Therefore, at the time of forming the box 5, the coating around the first connection portion 17 and the second connection portion 19 can be performed together, which is necessary for the coating around the first connection portion 17 and the second connection portion 19. Can save time and effort.

(Modification)
(1) In the above embodiment, an example in which both the periphery of the first connection portion 17 and the periphery of the second connection portion 19 are covered with one large cover 26 is shown, but other configurations may be adopted. it can. For example, as shown in FIG. 10, the periphery of the first connection portion 17 and the periphery of the second connection portion 19 may be individually covered with small covers 39 and 40. The covers 39 and 40 may be formed by applying an insulating resin around and around the first connection portion 17 and the second connection portion 19. The covers 39 and 40 may be formed by coating a metal around and around the first connecting portion 17 and around the second connecting portion 19. As the coating, for example, a plating process for coating a metal thin film can be employed. Metals include nickel (Ni), tin (Sn), chromium (Cr), zinc (Zn), titanium (Ti), manganese (Mn), tungsten (W), tantalum (Ta), molybdenum (Mo), niobium An alloy or compound containing one or more of (Nb) or tin (Sn) can be used.

(2) Moreover, in the said embodiment, the 1st terminal cover 36 which covers the circumference | surroundings of the 3rd connection part 35 is enclosed by the 1st area | region 27 of the upper surface of the 1st bus bar 15, and the internal peripheral surface of the 1st through-hole 12. Although an example in which the space is filled with a liquid insulating resin has been shown, other configurations may be employed. For example, as shown in FIG. 10, the insulating resin may be applied and formed only around and around the third connection portion 35. The same applies to the second terminal cover 38. FIG. 10 shows an example in which rod-shaped electrode terminals are used as the first electrode terminal 11 and the second electrode terminal 13. The first terminal cover 36 and the second terminal cover 38 are formed by coating the periphery of the third connection portion 35, the periphery of the fourth connection portion 37, and the periphery thereof with a metal containing tin and zinc. It may be. Further, the covers 39 and 40 may be formed by coating the periphery of the first connection portion 17, the periphery of the second connection portion 19, and the periphery thereof with a metal. Metals include nickel (Ni), tin (Sn), chromium (Cr), zinc (Zn), titanium (Ti), manganese (Mn), tungsten (W), tantalum (Ta), molybdenum (Mo), niobium An alloy or compound containing one or more of (Nb) or tin (Sn) can be used.

(3) Further, in the above-described embodiment, the example in which the first electrode terminal 11 is connected to the first bus bar 15 and the second electrode terminal 13 is connected to the second bus bar 18 is shown, but other configurations are adopted. You can also. For example, as shown in FIG. 11, the first electrode terminal 11 and the second electrode terminal 13 may be connected to the shunt resistor 16. By connecting to the shunt resistor 16, for example, the detection accuracy of the current detection device 1 can be improved as compared with the case of connecting to the first bus bar 15 or the second bus bar 18. FIG. 11 shows an example in which the first terminal cover 36 and the second terminal cover 38, the first electrode terminal 11, and the second electrode terminal 13, which are the same as those in FIG. 10, are used.

(4) In the above embodiment, the example in which the width and thickness of the first bus bar 15 and the second bus bar 18 are the same as the width and thickness of the shunt resistor 16 has been described. However, other configurations may be adopted. it can. For example, as shown in FIG. 12, the width of the first bus bar 15 and the width of the second bus bar 18 may be larger than the width of the shunt resistor 16. Further, as shown in FIG. 13, the thickness of the first bus bar 15 and the thickness of the second bus bar 18 may be larger than the thickness of the shunt resistor 16. By making the width and thickness of the first bus bar 15 and the second bus bar 18 larger than the width and thickness of the shunt resistor 16 and using the first bus bar 15 and the second bus bar 18 as heat sinks, heat generated by the shunt resistor 16 is generated. The first bus bar 15 and the second bus bar 18 can efficiently dissipate heat.

(5) Further, in the above-described embodiment, an example in which only the plating layer 42 is provided on the surface of the first bus bar 15 and the surface of the second bus bar 18 has been described, but other configurations may be employed. For example, as shown in FIG. 14, the connection surface of the first bus bar 15 with the shunt resistor 16, the connection surface of the second bus bar 18 with the shunt resistor 16, the connection surface of the shunt resistor 16 with the first bus bar 15 and the shunt resistor. Barrier layers 45, 46, and 47 for suppressing diffusion of tin included in the wax 41 may be provided on the connection surface with the 16 second bus bars 18. In FIG. 14, as an example, the entire first bus bar 15, second bus bar 18, and shunt resistor 16 are covered with barrier layers 45, 46, and 47.
In this case, the plating layer 42 of the first bus bar 15 and the second bus bar 18 is provided on each of the surface of the barrier layer 45 of the first bus bar 15 and the surface of the barrier layer 47 of the second bus bar 18. By providing the barrier layers 45, 46, 47, for example, when heat applied during brazing or heat generated during use of the shunt resistor 16 is generated, tin contained in the solder 41 is contained in the first bus bar 15. The diffusion into the second bus bar 18 and the shunt resistor 16 can be suppressed. Examples of the material of the barrier layers 45, 46, and 47 include nickel (Ni), titanium (Ti), manganese (Mn), tungsten (W), tantalum (Ta), molybdenum (Mo), and niobium (Nb). A metal having a high melting point such as an alloy or a compound containing one or a plurality thereof can be used.

  DESCRIPTION OF SYMBOLS 1 ... Current detection apparatus, 2 ... Housing, 3 ... Shunt structure, 4 ... Detection circuit, 5 ... Box body, 6 ... Cover body, 7 ... Lower space, 8 ... Upper space, 9 ... Internal partition, 10 ... Opening 11 ... 1st electrode terminal, 12 ... 1st through-hole, 13 ... 2nd electrode terminal, 14 ... 2nd through-hole, 15 ... 1st bus bar, 16 ... Shunt resistance, 17 ... 1st connection part, 18 ... 2nd bus bar, 19 ... 2nd connection part, 20 ... Battery post terminal (other bus bar), 21 ... Recess, 22 ... Connector, 23 ... Output terminal, 24 ... Other bus bar, 25 ... Remaining partition wall, 26 ... Cover, 27 ... 1st area | region, 28, 29 ... Linear part, 30 ... Intermediate | middle part, 31 ... 2nd area | region, 32, 33 ... Linear part, 34 ... Intermediate | middle part, 35 ... 3rd connection part, 36 ... 1st terminal cover, 37 ... 4th connection part, 38 ... 2nd terminal cover, 39, 40 ... cover, 41 ... brazing, 42 ... plating layer, 3 ... the underlying layer, 44 ... the outermost layer, 45 to 47 ... barrier layer

Claims (25)

Shunt resistance,
A first bus bar and a second bus bar connected to both ends of the shunt resistor,
The first bus bar and the second bus bar are shunt structures made of pure aluminum or aluminum alloy.   2. The shunt structure according to claim 1, wherein the first connection portion between the shunt resistor and the first bus bar and the second connection portion between the shunt resistor and the second bus bar are each configured by brazing connection. .   2. The shunt structure according to claim 1, wherein a first connection portion between the shunt resistor and the first bus bar and a second connection portion between the shunt resistor and the second bus bar are brazed. The brazing constituting the brazing connection contains tin,
The shunt according to any one of claims 1 to 3, wherein a plating layer containing tin is provided on a connection surface of the first bus bar with the shunt resistor and a connection surface of the second bus bar with the shunt resistor. Structure.   The shunt structure according to claim 4, wherein the shunt resistor is made of a copper alloy containing tin.   A connection surface of the first bus bar with the shunt resistor, a connection surface of the second bus bar with the shunt resistor, a connection surface of the shunt resistor with the first bus bar, and a connection of the shunt resistor with the second bus bar. The shunt structure according to any one of claims 2 to 5, further comprising a barrier layer on the surface for suppressing diffusion of tin contained in the wax.   The first connection portion is configured by brazing connection in which end portions of the shunt resistor and the first bus bar are vertically overlapped, and the second connection portion is formed by connecting the shunt resistor and the second bus bar. The shunt structure according to any one of claims 2 to 6, wherein the shunt structure is configured by brazing connection in which end portions are vertically overlapped.   The first connection portion is configured by brazing connection in which end surfaces of the shunt resistor and the first bus bar are butted together, and the second connection portion is in contact with end surfaces of the shunt resistor and the second bus bar. The shunt structure according to any one of claims 2 to 6, wherein the shunt structure is configured by brazing connection.   The periphery of the first connection part between the shunt resistor and the first bus bar and the periphery of the second connection part between the shunt resistor and the second bus bar are coated with insulating resin or metal. The shunt structure according to claim 1.   10. The shunt structure according to claim 1, wherein a width of the first bus bar and a width of the second bus bar are larger than a width of the shunt resistor.   11. The shunt structure according to claim 1, wherein a thickness of the first bus bar and a thickness of the second bus bar are larger than a thickness of the shunt resistor. A shunt resistor, a first bus bar and a second bus bar connected to both ends of the shunt resistor, a first electrode terminal connected to the first bus bar or the shunt resistor, and a connection to the second bus bar or the shunt resistor A shunt structure having a second electrode terminal formed;
A detection circuit connected to the first electrode terminal and the second electrode terminal and detecting a magnitude of a current flowing through the shunt resistor;
A housing for housing the shunt structure and the detection circuit;
The first bus bar and the second bus bar are current detection devices made of pure aluminum or aluminum alloy.   The current according to claim 12, wherein the periphery of the first connection portion between the shunt resistor and the first bus bar and the periphery of the second connection portion between the shunt resistor and the second bus bar are coated with an insulating resin or metal. Detection device.   The current detection device according to claim 13, wherein the insulating resin coating the periphery of the first connection portion and the periphery of the second connection portion is integral with the insulating resin constituting the housing.   The periphery of the third connection portion between the first bus bar and the first electrode terminal and the periphery of the fourth connection portion between the second bus bar and the second electrode terminal are coated with an insulating resin or metal. The current detection device according to any one of 1 to 14. The housing includes a first space for housing the shunt structure, a second space for housing the detection circuit, and an internal partition partitioning the first space and the second space,
The internal partition has a through hole through which the first electrode terminal and the second electrode terminal pass,
The first electrode terminal and the second electrode terminal are spaced apart from the inner peripheral surface of the through hole;
The current detection device according to claim 15, wherein the insulating resin coating the periphery of the third connecting portion and the periphery of the fourth connecting portion is an insulating resin different from the insulating resin constituting the casing.   The current detection according to claim 16, wherein the insulating resin coating the periphery of the third connection portion and the periphery of the fourth connection portion is an insulating resin having a lower elastic modulus than the insulating resin constituting the housing. apparatus.   18. The current detection device according to claim 12, wherein the first bus bar and the second bus bar are welded or bolted in surface contact with another bus bar made of an aluminum alloy. A shunt resistor and a shunt structure having a first bus bar and a second bus bar made of pure aluminum or aluminum alloy connected to both ends of the shunt resistor, and a first connection portion between the shunt resistor and the first bus bar. Coating the periphery of the second connecting portion between the shunt resistor and the second bus bar with an insulating resin;
Connecting a first electrode terminal to the first bus bar or the shunt resistor, and connecting a second electrode terminal to the second bus bar or the shunt resistor;
A method of manufacturing a current detection device, comprising: connecting a detection circuit for detecting a magnitude of a current flowing through the shunt resistor to each of the first electrode terminal and the second electrode terminal.   In coating the periphery of the first connection portion and the periphery of the second connection portion with an insulating resin, a part of the casing of the current detection device is in close contact with the shunt structure, and the first connection portion and the The method of manufacturing a current detection device according to claim 19, wherein the casing is integrally formed with the shunt structure so as to cover a periphery of the second connection portion. In connecting the first electrode terminal and the second electrode terminal, the first electrode terminal is connected to the first bus bar, and the second electrode terminal is connected to the second bus bar,
The method further comprises coating the periphery of the third connection portion between the first bus bar and the first electrode terminal and the periphery of the fourth connection portion between the second bus bar and the second electrode terminal with an insulating resin. A method for manufacturing the current detection device according to claim 20.   The coating of the periphery of the third connection portion and the periphery of the fourth connection portion is performed with the insulating resin when the periphery of the first connection portion and the periphery of the second connection portion are coated with the insulating resin. A method for manufacturing the current detection device according to claim 21. In coating the periphery of the first connection part and the periphery of the second connection part with an insulating resin, a first space for accommodating the shunt structure, a second space for accommodating the detection circuit, and A resin molded body made of an insulating resin having an internal partition wall that partitions the first space and the second space and has a through hole for passing the first electrode terminal and the second electrode terminal is formed in the housing. Formed as a body,
In connecting the first electrode terminal and the second electrode terminal, the first electrode terminal and the inner peripheral surface of the through hole are separated from each other, and the second electrode terminal and the inner peripheral surface of the through hole are separated from each other. Determining a connection position of the first electrode terminal and the second electrode terminal so as to be separated from each other;
The current detection device according to claim 21, wherein in coating the periphery of the third connection portion and the periphery of the fourth connection portion with an insulating resin, the coating is performed with an insulating resin different from the insulating resin constituting the housing. Manufacturing method.   24. The current detecting device according to claim 23, wherein the insulating resin that coats the periphery of the third connecting portion and the periphery of the fourth connecting portion is an insulating resin having a lower elastic modulus than the insulating resin that constitutes the casing. Production method. A method for mounting the current detection device according to any one of claims 12 to 18,
A mounting method for a current detection device, comprising: bringing a first bus bar and a second bus bar included in the shunt structure of the current detection device into surface contact with another bus bar made of an aluminum alloy and welding or bolting.

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