JP2012182051A - Bus bar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bus bar that has good heat dissipation and installation workability even when the bus bar is formed, for use as a power line, with a conductor having a large cross-section area and that prevents excessive heat generation due to poor electrical connection.SOLUTION: A bus bar 1 includes an intermediate portion 11 and terminal portions 12. The intermediate portion 11 is a conductor that is formed into a plate-like shape extending in a first direction and in part of which constricted portions 20 are provided to form grooves along a second direction intersecting the first direction. The terminal portions 12 are conductors that lead from both sides of the intermediate portion 11 in the first direction, and are to be connected to other component parts.

Description

  The present invention relates to a bus bar excellent in bending performance.

  In electric vehicles such as electric vehicles and hybrid vehicles, the current flowing through the power line tends to increase as the output of the battery increases. In order to prevent the power line from excessively generating heat due to a large current, it is necessary to employ a power line having a large cross-sectional area and excellent heat dissipation.

  For example, Patent Document 1 discloses a wire harness including a plurality of round electric wires arranged in parallel and a flat cylindrical corrugated tube that covers the periphery of the round electric wires. When multiple wires are arranged in parallel, the surface area of the part that forms the outline of the entire wire bundle becomes larger than when the multiple wires are bundled in a state where they are stacked in the vertical and horizontal directions, and heat dissipation of the entire wire bundle is achieved. Increases nature.

  On the other hand, a bus bar made of a plate-like conductor is often employed as a power line mounted on a vehicle. Since the bus bar has a flat shape, the conductor portion has a larger surface area and higher heat dissipation than a round electric wire having a round core wire having the same cross-sectional area.

JP 2010-47033 A

  By the way, as shown in Patent Document 1, when the power line is constituted by a bundle of wires made up of a plurality of covered wires arranged in parallel, the ends of the core wires in each of the plurality of covered wires are bound together electrically. Terminals to be connected are attached to both ends of the wire bundle.

  However, in the plurality of electric wires configured separately, a gap is easily generated between the core wires at their end portions. Therefore, when a terminal is attached to the core wire portion at the end of the wire bundle, some of the core wires are not sufficiently electrically connected to the terminal, and poor connection between the core wire of each wire and the terminal is likely to occur. . The poor connection between the core wire and the terminal of each electric wire causes excessive heat generation of the electric wire.

  On the other hand, when one power line is composed of one covered electric wire or one bus bar, such a power line is difficult to bend because it is hard, and has a problem that it is inferior in laying workability. Yes. In particular, the problem of difficulty in bending becomes more conspicuous as the length of a power line including one covered wire or one bus bar is shorter.

  The present invention provides a bus bar that is excellent in heat dissipation and laying workability even when a conductor has a large cross-sectional area for power lines, and that can prevent excessive heat generation due to poor electrical connection or the like. Objective.

The bus bar according to the present invention includes the following components.
(1) The first component is a conductor that is formed in a plate shape extending in the first direction, and in which a constricted portion that forms a groove along a second direction that intersects the first direction is formed in part. It is the intermediate part which is a part which consists of.
(2) A 2nd component is a terminal part which is a part which consists of a conductor connected on both sides in the 1st direction of an intermediate part, and is connected with another member.

  In the bus bar according to the present invention, it is conceivable that the constricted portion is formed on two relatively wide surfaces among the four surfaces of the plate-shaped intermediate portion.

  In the bus bar according to the present invention, it is also conceivable that the constricted portion is formed on two surfaces having a relatively narrow width among the four surfaces of the plate-like intermediate portion.

  By forming the bus bar in a flat shape, the ratio of the surface area to the cross-sectional area is increased, and heat dissipation is improved. Furthermore, in the bus bar according to the present invention, a constricted portion for forming a groove along a direction intersecting the longitudinal direction is formed at an intermediate portion of the bus bar. Since this constricted portion is easily elastically deformed so that the width of the groove expands and contracts, the intermediate portion of the bus bar is easily bent elastically at the constricted portion. That is, even if the bus bar according to the present invention is formed to be relatively short and thick, it has flexibility to bend elastically at the constricted portion.

  Furthermore, the bus bar according to the present invention is particularly easily bent at the constricted portion. Therefore, when the force of the direction which bends it with respect to the bus-bar which concerns on this invention is added, only a constriction part will bend elastically and other parts will not bend. As a result, when a force is applied to the bus bar according to the present invention, it is possible to prevent a bend mark from remaining on a flat portion other than the constricted portion. In addition, a bending trace means the site | part which does not return to an original shape after bending.

  In addition, since the terminal portions at both ends of the bus bar are originally connected to the intermediate portion, no electrical connection failure occurs in the terminal portion of the bus bar.

  Therefore, the bus bar according to the present invention has excellent heat dissipation and laying workability even when the conductor has a large cross-sectional area for power lines, and prevents excessive heat generation due to poor electrical connection or the like. it can.

  Further, in the bus bar according to the present invention, if the constricted portion is formed on two relatively wide surfaces among the four surfaces of the plate-shaped intermediate portion, the constricted portion is formed in the intermediate portion. It is easy to bend in the direction of the surface, that is, in the thickness direction. Such a bus bar is suitable when it is assumed that it is bent in the thickness direction.

  Further, in the bus bar according to the present invention, if the constricted portion is formed on two surfaces having a relatively narrow width among the four surfaces of the plate-shaped intermediate portion, that is, the side surface, the intermediate portion is the constricted portion. It is easy to bend in the direction of the surface on which is formed, that is, in the width direction. Such a bus bar is suitable when it is assumed that the bus bar is bent in the width direction.

It is a perspective view of bus bar 1 concerning a 1st embodiment of the present invention. It is a side view of the bus bar 1 in the middle of being attached to a terminal block. It is a perspective view of 1 A of bus bars which concern on 2nd Embodiment of this invention. It is a perspective view of bus bar 1B concerning a 3rd embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The following embodiment is an example embodying the present invention, and is not an example of limiting the technical scope of the present invention. The bus bar 1 according to the embodiment of the present invention is used, for example, as a power line that connects an inverter circuit and a motor or a generator in an electric vehicle, or as a power line that connects a battery and an inverter circuit.

<First Embodiment>
First, the configuration of the bus bar 1 according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2. The bus bar 1 is a conductor member made of metal such as copper, for example, and is formed to extend in one direction as shown in FIG. In the following description, the longitudinal direction of the bus bar 1 is referred to as a first direction, and the width direction and the thickness direction of the bus bar 1 are referred to as a second direction and a third direction, respectively. The second direction and the third direction are directions orthogonal to the first direction. 1 to 4, the first direction is the left-right direction.

  As shown in FIG. 1, the bus bar 1 includes an intermediate portion 11 and terminal portions 12 at both ends. The bus bar 1 is laid as a part of a power transmission path to each phase of an electric motor such as a three-phase motor.

  The intermediate portion 11 of the bus bar 1 is a portion made of a conductor that is formed in a plate shape extending in the first direction and in which a plurality of constricted portions 20 that form grooves along the second direction are formed. The constricted portion 20 in the bus bar 1 is formed on two relatively wide surfaces of the four surfaces of the plate-like intermediate portion 11, that is, the front surface and the back surface.

  The constricted portion 20 is formed, for example, by pressing or cutting a plate-like conductor. It is also conceivable that the bus bar 1 in which the constricted portion 20 is formed is manufactured by casting.

  On the other hand, the terminal part 12 is a part which consists of a conductor connected to the both ends of the intermediate part 11, and is connected with another member. The terminal portion 12 is formed with a terminal hole 12 </ b> A for being connected to a connection end at the front stage and the rear stage of the power transmission path by a fixing tool such as a bolt.

  That is, the bus bar 1 has a structure in which a constricted portion 20 that forms a groove along a direction intersecting the longitudinal direction is formed in a part of an intermediate region excluding a partial region at both ends of one plate-like conductor. Have

  FIG. 2 is a side view of the bus bar 1 in the middle of being attached to the front and rear terminal blocks 9 of the power transmission path. In the example shown in FIG. 2, the stud bolt 91 provided on the terminal block 9 is passed through the terminal hole 12 </ b> A of the terminal portion 12 in the bus bar 1, and the nut 8 is attached to the stud bolt 91. Thereby, the terminal portion 12 is fixed to the terminal block 9 and is electrically connected to the terminal block 9.

  Since the bus bar 1 has a flat cross section, the ratio of the surface area to the cross sectional area is large, and the heat dissipation is high.

  Further, a constricted portion 20 that forms a groove along the second direction intersecting the longitudinal direction is formed in the intermediate portion 11 of the bus bar 1. As shown in FIG. 2, the constricted portion 20 of the bus bar 1 is easily elastically deformed so that the width of the groove formed by the constricted portion 20 expands and contracts, so that the intermediate portion 11 of the bus bar 1 has the constricted portion 20. It is easy to bend elastically. That is, even if the bus bar 1 is formed to be relatively short and thick, the constricted portion 20 has flexibility to bend elastically in the thickness direction.

  Therefore, as shown in FIG. 2, in the laying operation of the bus bar 1, the terminal portion 12 can be positioned at a target position while the intermediate portion 11 is elastically bent. As a result, the bus bar 1 is excellent in laying workability compared to a conventional bus bar that cannot be bent easily.

  Further, the bus bar 1 is particularly easily bent at the constricted portion 20. Therefore, when the force of the direction which bends it with respect to the bus-bar 1 is added, only the constriction part 20 will bend elastically and other parts will not bend. As a result, when a force is applied to the bus bar 1, it is possible to prevent a bend mark from remaining on a flat portion other than the constricted portion 20.

  Further, the terminal portions 12 at both ends of the bus bar 1 are portions that are originally connected to the intermediate portion 11. Therefore, unlike the case where terminals are attached to a bundle of a plurality of core wires, there is no electrical connection failure in the terminal portion 12 of the bus bar 1.

  By the way, in the bus bar 1, about the part in which the constriction part 20 was formed, the cross-sectional area of a conductor becomes smaller than the cross-sectional area of the conductor of the part before and behind that. However, as a result of the experiment, when the width of the groove formed by the constricted portion 20 is very narrow, the increase in impedance in the portion where the constricted portion 20 is formed is small enough to be ignored for the entire bus bar 1. know. Therefore, in the bus bar 1, when the narrow neck portion 20 is formed, excessive heat generation due to the flowing current is prevented.

  As shown above, the bus bar 1 is excellent in heat dissipation and laying workability even when the cross-sectional area is large for power lines, and prevents excessive heat generation due to poor electrical connection or the like. It has the characteristics that can be done.

Second Embodiment
Next, a bus bar 1A according to a second embodiment of the present invention will be described with reference to FIG. This bus bar 1A is different from the bus bar 1 shown in FIG. 1 in the surface on which the constricted portion is formed in the intermediate portion 11. 3, the same components as those shown in FIG. 1 are denoted by the same reference numerals. Hereinafter, only the differences between the bus bar 1A and the bus bar 1 will be described.

  Like the bus bar 1, the bus bar 1A extends in the first direction and is formed in a plate shape. The bus bar 1A is formed of a conductor having a plurality of constricted portions 21 formed in a part thereof, and continues to both ends of the intermediate portion 11. It is a member made of a conductor and formed with a conductor and a terminal portion 12 which is a portion connected to another member.

  However, the constricted portion 21 of the bus bar 1A is formed on all four sides of the plate-like intermediate portion 11. That is, the constricted portion 21 of the bus bar 1 </ b> A forms a groove along each of the second direction (width direction) and the third direction (thickness direction) over the entire circumference of the intermediate portion 11.

  Since the constricted portion 21 of the bus bar 1A is easily elastically deformed so that the width of the groove formed by the constricted portion 21 expands and contracts, the intermediate portion 11 of the bus bar 1A has a width direction of the intermediate portion 11 in the constricted portion 21. Flexibility to bend elastically in both thickness directions. When such a bus bar 1A is employed, the same effects as those obtained when the bus bar 1 is employed are obtained.

<Third Embodiment>
Next, a bus bar 1B according to a third embodiment of the present invention will be described with reference to FIG. The bus bar 1B is different from the bus bar 1 shown in FIG. 1 in the surface on which the constricted portion is formed in the intermediate portion 11. 4, the same components as those shown in FIG. 1 are given the same reference numerals. Hereinafter, only differences between the bus bar 1B and the bus bar 1 will be described.

  Similarly to the bus bar 1, the bus bar 1B extends in the first direction and is formed in a plate shape. The intermediate portion 11 is formed of a conductor having a plurality of constricted portions 22 formed in a part thereof, and continues to both ends of the intermediate portion 11. It is a member made of a conductor and formed with a conductor and a terminal portion 12 which is a portion connected to another member.

  However, the constricted portion 21 of the bus bar 1B is formed on two relatively narrow surfaces of the four surfaces of the plate-shaped intermediate portion 11, that is, two side surfaces. That is, the constricted portion 22 of the bus bar 1B forms a groove along the third direction (thickness direction) orthogonal to the first direction in the intermediate portion 11.

  Since the constricted portion 22 of the bus bar 1B is easily elastically deformed so that the width of the groove formed by the constricted portion 22 expands and contracts, the intermediate portion 11 of the bus bar 1B extends in the width direction of the intermediate portion 11 at the constricted portion 22. Flexibility to bend elastically. When such a bus bar 1B is employed, the same effects as when the bus bar 1 is employed are obtained.

<Others>
In the embodiment shown above, the bus bars 1, 1 </ b> A, 1 </ b> B have a plurality of constricted portions 20, 21, 22 at the intermediate portion 11. However, it is also conceivable that only one constricted portion 20, 21, 22 is formed in the intermediate portion 11 of the bus bars 1, 1A, 1B.

  It is also conceivable that the bus bars 1, 1A, 1B are used in a state where the intermediate portion 11 is covered with an insulating member. The insulating member may be composed of an insulating elastic member made of, for example, rubber or an elastomer (elastic polymer) that is a rubber-based material. Elastomers include vulcanized rubbers such as natural rubber and synthetic rubber, urethane rubber, silicone rubber and fluoro rubber. In general, a thermosetting resin-based elastomer is used as a material for an insulating member made of elastomer. If the insulating member is a member made of an elastomer having excellent flexibility, the flexibility of the intermediate portion 11 of the bus bars 1, 1 </ b> A, 1 </ b> B is not hindered.

  The insulating member covering the intermediate portion 11 of the bus bars 1, 1A, 1B is made of a resin such as polyamide (PA), polypropylene (PP), polybutylene terephthalate (PBT), ABS resin, or polyethylene (PE). Is also possible. It is also conceivable that the insulating member covering the intermediate portion 11 is a heat shrinkable tube.

  The bus bars 1, 1A, 1B may be used in a state where the intermediate portion 11 is covered with an insulating member and the periphery of the insulating member is covered with a shield member such as a braided wire. Further, the bus bars 1, 1A, 1B are covered with a shielding member such as a braided wire around the insulating member covering the intermediate portion 11, and further, the outer side is insulative such as a resin protective tube or tape having flexibility. It may be used in a state covered with the exterior member.

  It is also conceivable that a plurality of bus bars 1, 1 </ b> A, 1 </ b> B are arranged in parallel along a single plane and are used in a state where their intermediate portions 11 are covered and connected by an insulating member. It is done.

1, 1A, 1B Bus bar 8 Nut 9 Terminal block 11 Bus bar middle part 12 Bus bar terminal part 12A Terminal hole 20, 21, 22 Neck part 91 Stud bolt

Claims (3)

An intermediate portion formed of a conductor formed with a constricted portion formed in a plate shape extending in a first direction and partially forming a groove along a second direction intersecting the first direction;
A bus bar comprising: a terminal portion which is a portion made of a conductor continuous on both sides in the first direction of the intermediate portion and connected to another member.   2. The bus bar according to claim 1, wherein the constricted portion is formed on two relatively wide surfaces among four surfaces of the plate-like intermediate portion.   The bus bar according to claim 1 or 2, wherein the constricted portion is formed on two surfaces having a relatively narrow width among the four surfaces of the plate-like intermediate portion.

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