JP2014011128A - Washer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a washer which can be crimped to a cable while preventing deformation and damage when handling, and can reduce contact resistance.SOLUTION: The washer includes a flat plate part 21 consisting of a copper plate having a thickness in the range of 100-300 μm and provided with a bolt through hole 23, a cable crimp part 22 formed integrally with the flat plate part 21, and sidewall parts 24-26 provided on the periphery of the flat plate part 21. The sidewall parts 24-26 are provided at least in two directions not in parallel with each other.

Description

  The present invention relates to a washer interposed between conductive members in connection between conductive members by screwing or the like, and more particularly to a washer suitable for connecting a battery terminal and a bus bar.

  In connecting the conductive members, it is important to reduce the contact resistance. FIG. 13 shows the structure described in Patent Document 1 as a configuration for reducing such contact resistance. In this example, the power supply bus bars 11 and 12 are fastened by using screws 13 to electrically When connecting to the metal sheet 14, the metal sheet 14 is interposed between the contact surfaces 11a, 12a of the power supply bus bars 11, 12 facing each other.

  The metal sheet 14 is made of a plastically deformable metal material such as solder, and has a thickness of about 40 μm, for example. With such a metal sheet 14 interposed, the power supply bus bars 11 and 12 and the metal sheet 14 are pressure-bonded to each other by the screw 13. As a result, the metal sheet 14 crushed by plastic deformation enters the minute irregularities on the contact surfaces 11a and 12a of the power supply bus bars 11 and 12, and fills the irregularities without gaps, and the inclination of the contact surfaces 11a and 12a. Accordingly, the metal sheet 14 is plastically deformed, so that the contact resistance can be reduced.

JP 2011-159544 A

  By the way, in the connection of a battery terminal such as a lithium ion battery and a bus bar by screwing, there is a strong demand for low contact resistance, and on the other hand, a configuration capable of monitoring the battery voltage is also required.

  In order to monitor the voltage of the battery, it is necessary to connect a cable to the battery terminal. In this case, if a washer like the structure of the metal sheet 14 shown in FIG. Connections can be made easily and at the same time the contact resistance can be reduced.

  However, a washer made of a metal material that is thin like the metal sheet 14 shown in FIG. 13 and easily deforms plastically, such as solder, has low mechanical strength of the washer as a whole. Problems such as deformation and breakage are extremely likely to occur.

  In order to avoid such deformation and breakage, it is conceivable that the washer is made of, for example, a copper alloy or that the plate thickness is increased, but this increases the contact resistance.

  Therefore, even if a washer having the configuration of the metal sheet 14 shown in FIG. 13 is used to reduce the contact resistance, the washer cannot be crimped to the voltage monitoring cable. It had to be connected to battery terminals and bus bars by soldering or welding. In this respect, the work is complicated and time-consuming.

  In view of this problem, an object of the present invention is to provide a washer capable of reducing contact resistance and capable of being crimped to a cable and preventing deformation and breakage during handling even when crimped to the cable. There is.

According to the invention of claim 1, the washer is made of a copper plate having a thickness of 100 μm to 300 μm, a flat plate portion provided with a bolt through hole, a cable crimping portion integrally formed on the flat plate portion, and a flat plate portion. The side walls are provided at least in two directions that are not parallel to each other.
In the invention of claim 2, in the invention of claim 1, the cable crimping portion is formed to extend from the flat plate portion.

In the invention of claim 3, in the invention of claim 2, the flat plate portion has a three-layer structure in which a conductive material softer than copper is sandwiched between copper plates which are doubled by folding a copper plate.
In the invention of claim 4, in the invention of claim 1, the cable crimping portion is formed by cutting out the flat plate portion in the flat plate portion, and the cable crimping portion is connected and supported by the flat plate portion on both the cable leading end side and the cable outlet side. It is supposed to be.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects of the present invention, of the side walls provided in at least two directions that are not parallel to each other, the side wall in at least one direction is the other side wall and the flat plate. On the other hand, it is assumed that it is launched in the opposite direction.
According to the invention of claim 6, in the invention of any one of claims 1 to 5, the flat plate portion has a square shape.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects, the flat plate portion is extruded to form a rib.
According to an eighth aspect of the present invention, in any one of the first to seventh aspects, a spring piece is cut and raised on the flat plate portion.

  In the invention of claim 9, in the invention of claim 8, the extension of the spring piece is the radial direction of the bolt through hole, the bolt through hole side is the base end, and the spring piece protrudes on one surface of the flat plate portion; The bolt through hole side is a free end, and spring pieces protruding on the other surface of the flat plate portion are alternately arranged around the bolt through hole.

In the invention of claim 10, in any invention of claims 1 to 9, tin plating is applied to the copper plate.
In the invention of claim 11, in the invention of claim 10, the thickness of the tin plating is 2 μm or less.

  According to the washer according to the present invention, the mechanical strength is improved because the side wall is reinforced. Therefore, even if it is crimped to the cable, deformation and breakage during handling can be prevented.

  Therefore, the washer according to the present invention can be crimped to, for example, a voltage monitoring cable, which facilitates the connection of the voltage monitoring cable to the battery terminal, which has conventionally used methods such as soldering and welding. At the same time, for example, the contact resistance between the battery terminal and the bus bar can be reduced.

1A is a perspective view showing a first embodiment of a washer according to the present invention, and B is a perspective view of A as viewed from the back side. FIG. The perspective view which shows the state by which the washer shown in FIG. 1 was crimped | bonded to the cable. 1A is a perspective view for explaining an example of mounting the washer shown in FIG. 1 on a battery unit (before mounting), B is a perspective view after mounting A, and C is a partial enlarged view of B. FIG. The perspective view which shows the example of mounting of the washer shown in FIG. 1 with respect to a some battery unit. 1A is a perspective view (before mounting) for explaining an example of mounting the washer (partially changed) shown in FIG. 1 on a laminate cell, B is a perspective view after mounting A, and C is a partially enlarged view of B. FIG. The perspective view which shows the example of mounting of the washer (partially change) shown in FIG. 1 with respect to a some laminate cell. The partial expanded sectional view of FIG. 5A is a perspective view of a laminate cell having a terminal position different from that of the laminate cell in FIG. 5A, and FIG. 5B is a perspective view showing a mounting example of the washer (partially changed) shown in FIG. A is a perspective view showing a second embodiment of the washer according to the present invention, and B is a perspective view showing a state in which the washer shown in A is crimped to a cable. FIG. 9B is a perspective view showing a modification of the washer shown in FIG. 9A. The perspective view which shows the 3rd Example of the washer by this invention. A is a perspective view showing a fourth embodiment of a washer according to the present invention, and B is a partially enlarged sectional perspective view of A. FIG. The perspective view for demonstrating the prior art example of the connection structure of electrically conductive members.

  Embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a first embodiment of a washer according to the present invention. A washer 20 is formed by subjecting a copper plate (pure copper plate) to a required pressing process or the like.

  The washer 20 includes a flat plate portion 21 having a rectangular shape and a cable crimping portion 22 formed integrally with the flat plate portion 21. In this example, the cable crimping portion 22 is formed to be extended from one side of the flat plate portion 21, and is formed with a connecting portion 22a that is gradually narrowed, an extending portion 22b that is extended from the tip of the connecting portion 22a, and an extending portion. A pair of pressure-bonding pieces 22c formed by bending from both ends in the width direction of the extending portion 22b at the tip side portion of the portion 22b is provided.

  Bolt through holes 23 are formed in the flat plate portion 21, and side wall portions 24 to 26 are provided on the periphery of the flat plate portion 21. The side wall portions 24 to 26 are formed on the other three sides except for one side where the cable crimping portion 22 is extended, and the side wall portions 24 and 25 located on two opposite sides of the flat plate portion 21 are flat plates in this example. It is raised so as to protrude to the surface 21 a side of the portion 21. On the other hand, the side wall part 26 located on the side orthogonal to the side where the side wall parts 24 and 25 are located protrudes to the back surface side 21b of the flat plate part 21, that is, the opposite direction to the side wall parts 24 and 25 with respect to the flat plate part 21. Has been launched.

  Side wall portions 27 and 28 are also provided at both ends in the width direction of the cable crimping portion 22. As shown in FIG. 1A, the side wall portions 27 and 28 are provided from the connecting portion 22a to the extending portion 22b and to the front of the pair of crimping pieces 22c. These side wall portions 27 and 28 are raised in the same direction as the side wall portions 24 and 25.

  The side walls 24 to 28 described above are formed by, for example, drawing, and in this example, the ribs 31 and 32 are formed by being pushed out to the flat plate part 21 by pressing. The ribs 31 and 32 are formed into an oval shape, and the longitudinal direction thereof is parallel to the side wall portions 24 and 25 and is formed closer to the cable crimping portion 22.

  FIG. 2 shows a state in which the washer 20 is crimped to the cable 40 and the cable 40 is connected to the washer 20. The cable 40 is connected to the washer 20 by caulking the pair of crimping pieces 22c as shown in FIG.

  In the above configuration, the thickness of the pure copper plate forming the washer 20 is selected within the range of 100 μm to 300 μm. If the flat plate portion 21 of the washer 20 having such a material and thickness is sandwiched between the connecting surfaces of the conductive members that connect each other (between the contact surfaces), the washer 20 is deformed to follow the properties of the connecting surface. Contact resistance can be lowered.

  The washer 20 is handled in a state where it is crimped to the cable 40 in the process. In this example, the washer 20 is reinforced by the side walls 24 to 28 and the ribs 31 and 32. For example, the washer 20 is bent. And damage can be prevented.

  If the plate thickness of the washer 20 is thinner than 100 μm, the followability with respect to the contact surface is too poor, and if it is thicker than 300 μm, the crimping work of the crimping piece 22c of the cable crimping portion 22 becomes difficult and workability is improved. Since it deteriorates, it is preferable to select within the range of 100 μm to 300 μm as described above.

  FIG. 3 shows a use example in which the above washer 20 is used. In FIG. 3, reference numeral 50 denotes a battery unit (cell unit) of a lithium ion battery. Reference numeral 60 denotes a bus bar, and reference numeral 70 denotes a bolt for fixing the bus bar 60 to the terminals 51 and 52 of the battery unit 50. The washer 20 is used by being sandwiched between the terminals 51 and 52 of the battery unit 50 and the bus bar 60. The washer 20 is sandwiched between the back surface 21b of the flat plate portion 21 on the bus bar 60 side.

  The bus bar 60 and the terminals 51 and 52 are normally bolted directly. Of the terminals 51 and 52, the positive terminal 51 is generally made of aluminum, and the size of the contact resistance is particularly problematic. Therefore, there is a problem that even if the bolt is fastened with high torque, the contact resistance is good and does not drop stably. On the other hand, the contact resistance can be lowered by sandwiching the washer 20 as described above.

  If the washer 20 to which the cable 40 is connected is sandwiched between the terminals 51 and 52 and the bus bar 60, the voltage of the battery unit 50 can be monitored via these cables 40. A troublesome and time-consuming work such as connecting a cable for voltage monitoring to the terminals 51 and 52 by soldering or welding becomes unnecessary.

  In addition, when the bolt is fastened, the side wall portion 26 of the washer 20 is caught on the side surface of the bus bar 60 as shown in an enlarged view in FIG. 3C, thereby preventing the washer 20 from rotating. Further, the ribs 31 and 32 are provided so as to be located just at the connection surface edge of the terminals 51 and 52 or the connection surface edge of the bus bar 60 in a state where the washer 20 is sandwiched between the terminals 51 and 52 and the bus bar 60. Thereby, it is possible to prevent the washer 20 from being broken at the connection surface edge of the terminals 51 and 52 and the connection surface edge of the bus bar 60, and the strength is further improved in that respect.

  FIG. 4 shows a state in which a washer 20 having a cable 40 connected to each terminal 51, 52 of the battery unit 50 is arranged, and a plurality of battery units 50 are connected in series by a bus bar 60.

  FIG. 5 shows an example of mounting a washer as described above on a laminate cell. In FIG. 5, reference numeral 80 denotes a laminate cell. Reference numeral 90 denotes a bus bar, and reference numerals 100 and 110 denote bolts and nuts for fixing the bus bar 90 to the terminals 81 and 82 of the laminate cell 80.

  The washer 20 ', 20' 'has a shape partially changed from the washer 20 shown in FIG. The washer 20 ′ has a shape in which the side wall portion 25 in the washer 20 is deleted, and the washer 20 ″ has a shape in which the side wall portion 24 in the washer 20 is deleted.

  The washers 20 ′ and 20 ″ are used by being sandwiched between the terminals 81 and 82 of the laminate cell 80 and the bus bar 90. The washers 20 ′ and 20 ″ have the back surface 21b of the flat plate portion 21 on the bus bar 90 side, and the side wall portion 26 is caught on the side surface of the bus bar 90 as shown in FIG. ”Rotation can be prevented.

  By using the washers 20 ′ and 20 ″ to which the cable 40 is connected, the contact resistance can be lowered also in this example, and the voltage of the laminate cell 80 can be easily monitored via the cable 40.

  FIG. 6 shows a state in which a plurality of laminate cells 80 are connected in series by bus bars 90, with washers 20 ′ and 20 ″ to which cables 40 are connected, arranged at the respective terminals 81 and 82 of the laminate cell 80. In this example, the bus bar 90 is bent into a U-shape as shown in FIG. FIG. 7 is an enlarged view of the cross section of the bolt fastening portion on the terminal 82 side of the laminate cell 80 in FIG.

  FIG. 8A shows a laminate cell 120 having a terminal position different from that of the laminate cell 80, and the pair of terminals 121 and 122 are positioned separately in the vertical direction. In FIG. 8B, as in FIG. 6, washers 20 ′ and 20 ″ to which the cable 40 is connected are arranged at the respective terminals 121 and 122 of the laminate cell 120, and a plurality of laminate cells 120 are connected in series by the bus bar 90. The state is shown.

  Next, a second embodiment of the washer according to the present invention will be described with reference to FIG. 9A.

  In this example, the flat plate portion 131 of the washer 130 is formed with a bolt through hole 134 and side wall portions 135 to 137 are provided, and the cable crimping portion 132 is integrally formed by cutting out a part of the flat plate portion 131. Has been. The cable crimping part 132 is located in the window 133 reinforced by the side wall parts 135 and 136 formed on the long sides facing each other of the flat plate part 131 as shown in FIG. 9A. The side wall portion 137 is formed on the short side on the side where the bolt through hole 134 is located so as to rise in the opposite direction to the side wall portions 135 and 136 with respect to the flat plate portion 131.

  The cable crimping part 132 was bent up from both ends in the width direction of the connecting part 132a, the extension part 132b, and the extension part 132b that were gradually narrowed, like the cable crimping part 22 of the washer 20 shown in FIG. And a pair of crimping pieces 132c. In FIG. 9A, the pair of crimping pieces 132c is shown as being caulked.

  In the cable crimping part 132, the connecting part 132a is connected and supported by the flat plate part 131, and the extending part 132b is also connected and supported by the flat plate part 131. That is, both the leading end side of the cable to be crimped and the leading side of the cable are flat part. 131 is connected and supported.

  Since both ends of the cable crimping part 132 are thus reinforced by the side wall parts 135 and 136, the strength of the cable crimping part 132 is increased and the twisting is prevented in this example. .

  FIG. 9B shows a state in which the cable 40 is connected to the washer 130 having the above-described configuration.

  FIG. 10 shows a modification of the washer 130 shown in FIG. 9A. In this example, the flat plate portion 131 ′ is not square, and one side of the square (the short side on the side where the bolt through hole 134 is located) is half. It has been changed to an arc shape. This shape is adapted to the shape of the terminal in which the washer 130 'is sandwiched, and if such a shape is adopted, the portion of the washer 130' protruding from the terminal can be reduced.

  Next, a third embodiment of the washer according to the present invention will be described.

  FIG. 11 shows a third embodiment of the washer according to the present invention. Parts corresponding to those in FIG. 1A are denoted by the same reference numerals, and description thereof is omitted.

  In this example, spring pieces 33 and 34 are cut and raised on the flat plate portion 21. The extending direction of the spring pieces 33 and 34 is the radial direction of the bolt through hole 23. The spring piece 33 has a base end on the bolt through hole 23 side and is formed so as to protrude on the surface 21 a of the flat plate portion 21, whereas the spring piece 34 has a free end on the bolt through hole 23 side and has a flat plate shape. It is formed so as to protrude on the back surface 21 b of the part 21.

  As shown in FIG. 11, these spring pieces 33, 34 are alternately arranged around the bolt through hole 23. In this example, six spring pieces 33, 34 are formed. The six spring pieces 33 are positioned symmetrically with respect to the center of the bolt through hole 23, and the six spring pieces 34 are also positioned symmetrically with respect to the center of the bolt through hole 23. Thus, by providing symmetry to the arrangement of the spring pieces 33, 34, the deformation of the washer 140 at the time of bolt fastening is balanced.

  When the diameter of the terminal of the battery unit is small, for example, when the washer 140 is disposed, if the direction of the spring piece 34 is opposite to the bolt through hole 23 side, the spring tip protrudes from the battery unit terminal. Since there is a possibility that the effect of reducing the resistance value may be lost, the direction of the spring piece 34 having a free end on the bolt through hole 23 side is effective (convenient) for contact with the terminal. When the connecting surface into which the washer 140 is sandwiched is sufficiently wide, the direction of the spring piece in the radial direction of the bolt through hole 23 does not need to be changed alternately inward and outward as shown in FIG.

  FIG. 12 shows a fourth embodiment of the washer according to the present invention. Parts corresponding to those in FIG. 1A are denoted by the same reference numerals, and description thereof is omitted.

  In this example, as shown in FIG. 12B, the flat plate portion 21 ′ has a three-layer structure in which a conductive material 35 softer than copper is sandwiched between copper plates which are doubled by folding a copper plate. . The conductive material 35 is, for example, a solder sheet or a silver (Ag) paste, and has high conductivity.

  If the washer 150 having such a configuration is used, the front surface 21a and the back surface 21b of the flat plate portion 21 ′ independently follow each of the connection surfaces between which the washer 150 is sandwiched, and thus the contact resistance can be satisfactorily reduced. Can do.

  Although various embodiments have been described above, the thickness of the copper plate constituting the washer is selected within the range of 100 μm to 300 μm.

  Note that tin (Sn) plating may be applied to the copper plate. If tin plating is applied, followability to the connection surface can be improved, and contact resistance can be further reduced. The thickness of the tin plating is preferably smaller than the crystal grain size of the tin plating in the direction parallel to the plate surface (tin plating forming surface) of the copper plate in order to obtain a good reduction effect of the contact resistance by the tin plating, for example, 2 μm. It is as follows.

11, 12 Feed bus bar 11a, 12a Contact surface 13 Screw 14 Metal sheet 20, 20 ', 20''Washer 21, 21' Flat plate portion 21a Front surface 21b Rear surface 22 Cable crimping portion 22a Connection portion 22b Extension portion 22c Crimping piece 23 Bolt penetration Holes 24 to 28 Side walls 31, 32 Ribs 33, 34 Spring pieces 35 Conductive material 40 Cable 50 Battery unit 51, 52 Terminal 60 Bus bar 70 Bolt 80 Laminate cell 81, 82 Terminal 90 Bus bar 100 Bolt 110 Nut 120 Laminate cell 121, 122 terminal 130, 130 'washer 131, 131' flat plate part 132 cable crimping part 132a connection part 132b extension part 132c crimping piece 133 window 134 bolt through hole 135-137 side wall part 140,150 washer

Claims (11)

The plate thickness is made of a copper plate in the range of 100 μm to 300 μm,
A flat plate portion provided with bolt through holes;
A cable crimping portion integrally formed with the flat plate portion;
A side wall provided on the periphery of the flat plate portion,
The washer according to claim 1, wherein the side walls are provided at least in two directions that are not parallel to each other. The washer according to claim 1,
The cable washer is formed by extending from the flat plate portion. The washer according to claim 2,
The washer according to claim 1, wherein the flat plate portion has a three-layer structure in which a conductive material softer than copper is sandwiched between copper plates which are doubled by folding the copper plate. The washer according to claim 1,
The cable crimping portion is formed in the flat plate portion by cutting out the flat plate portion,
A washer characterized in that the cable crimping portion is connected and supported by the flat plate portion at both the cable leading end side and the cable leading side. The washer according to any one of claims 1 to 4,
Of the side wall portions provided at least in two directions that are not parallel to each other, the side wall portion in at least one direction is raised in the opposite direction with respect to the other side wall portions and the flat plate portion. Washer. The washer according to any one of claims 1 to 5,
A washer characterized in that the flat plate portion has a rectangular shape. The washer according to any one of claims 1 to 6,
A washer, wherein the flat plate portion is extruded to form a rib. The washer according to any one of claims 1 to 7,
A washer having a spring piece cut and raised on the flat plate portion. The washer according to claim 8,
The extension direction of the spring piece is the radial direction of the bolt through hole,
The bolt through hole side is a base end, the spring piece protruding on one surface of the flat plate portion, and the bolt through hole side is a free end, and the spring piece protruding on the other surface of the flat plate portion is the A washer characterized by being alternately arranged around the bolt through hole. The washer according to any one of claims 1 to 9,
A washer, wherein the copper plate is tin-plated. The washer according to claim 10,
A washer having a tin plating thickness of 2 μm or less.

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