JP2015170540A - flexible conductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve mechanical flexibility and radiation performance while suppressing increase of a resistance value of a flexible conductor.SOLUTION: A flexible conductor 20 in which a plurality of strip-shaped metal thin plates 1 are laminated, and both ends in longitudinal directions of the metal thin plates 1 are bundled, respectively to be made into electrode parts, has a stripe-shaped folded part 2 folded and formed in width directions of the metal thin plates 1. The folded part 2 flexibly formed in the longitudinal directions of the metal thin plates 1 is, for example, accordion fold structure. The folded part 2 projecting from top surfaces of flat surface parts of the metal thin plates 1 contacts lower surfaces of flat surface parts of other thin plates 1 overlapped on the metal thin plates 1, and gap parts 4 are generated among the metal thin plates 1 according to a projection amount of the folded part 2. Exothermic heat in conduction can be radiated via a ventilation passage to be constituted of the gap part 4 by arranging the flexible conductor 20 so that the flexible conductor 20 is conducted in a state where the folded part 2 is compressed.

Description

  The present invention relates to a flexible conductor for energizing a large current that is used in an electrical switching device and connects between a driving terminal and a fixed terminal while maintaining mobility.

In an electrical switchgear, a configuration in which an energized state is switched on / off by operating an electrical contact with a drive mechanism is generally used. The electrical contacts operated by the drive mechanism must be flexibly connected to an external fixed conductor so as not to impair mobility. For the above-mentioned use, for example, a flexible conductor formed by laminating strip-shaped copper thin plates and welding both ends and having current-carrying performance while maintaining mechanical flexibility is used.
Since the current always flows when the electrical switching device is on, the flexible conductor needs to be designed so that the device temperature does not excessively increase due to Joule heat generation of the conductor.

According to the prior art, a measure for reducing electric resistance by using a plurality of flexible conductors in parallel has been disclosed (for example, see Patent Document 1).
Further, according to another conventional technique, a measure for promoting heat dissipation by disposing a spacer between the stacked copper thin plates to provide a gap is disclosed (for example, see Patent Document 2).

JP 58-155612 A Japanese Patent Laid-Open No. 10-334743

In order to suppress the temperature rise, if the measures such as increasing the width and the laminated thickness of the flexible conductor and increasing the number of parallel connections of the copper thin plates constituting the conductor as in the prior art 1, The equivalent cross-sectional area increases and the mechanical flexibility decreases.
Further, in the structure in which the spacer is provided between the copper thin plates as in Reference 2, it is necessary to increase the thickness of the entire flexible conductor by the spacer in order to keep the gap between the copper thin plates constant. When the thickness of the flexible conductor increases, it is necessary to provide a large circumferential length difference between the copper thin plate on the inner peripheral side and the copper thin plate on the outer peripheral side when the flexible conductor is bent. The length of the conductor increased. That is, there is a problem that the resistance value and the heat generation amount of the flexible conductor increase.

  The present invention has been made to solve the above-described problems, and realizes a flexible conductor that achieves both improved mechanical flexibility and improved heat dissipation while suppressing an increase in the resistance value of the flexible conductor. The purpose is to do.

  The flexible conductor according to the present invention is a flexible conductor in which a plurality of strip-shaped thin metal plates are laminated and both end portions in the longitudinal direction of the thin metal plate are bundled to form an electrode portion, and the thin metal plate is in the width direction. It is characterized in that it has a streak-like bent portion that is bent and formed in such a manner that the bent portion can be extended and contracted in the longitudinal direction of the thin metal plate.

  According to the flexible conductor of the present invention, it is not necessary to provide a difference in the circumference of the metal thin plate even when the flexible conductor is bent by the bending portion formed on the metal thin plate so as to be stretchable. The increase in length can be suppressed, and the flexibility of the flexible conductor itself can be improved. Furthermore, a gap can be secured between the metal thin plates by the bent portion, and the heat dissipation of the flexible conductor can be improved.

It is a perspective view which shows the expansion | extension state and compression state of the flexible conductor by Embodiment 1 of this invention. It is sectional drawing which shows the structure of the non-energized state and the energized state of the electrical switchgear using the flexible conductor of Embodiment 1 of this invention. It is sectional drawing which shows the expansion | extension state of the flexible conductor in Embodiment 2 of this invention. It is sectional drawing which shows the compression state of the flexible conductor in Embodiment 2 of this invention. It is sectional drawing which shows the modification of the flexible conductor of Embodiment 2 of this invention. It is a perspective view of the flexible conductor of Embodiment 3 of this invention. It is principal part sectional drawing which shows the ventilation path | route of the flexible conductor of Embodiment 3 of this invention. It is a perspective view of the flexible conductor of Embodiment 4 of this invention. It is a principal part expanded sectional view of the thin metal plate which comprises the flexible conductor of Embodiment 5 of this invention, and is a figure which shows an example of a circular arc type bending process part.

Embodiment 1 FIG.
Hereinafter, the flexible conductor in Embodiment 1 of this invention is demonstrated using FIG. 1 and FIG. FIG. 1 is a perspective view of a flexible conductor (shunt conductor, current-carrying shunt) 20 according to Embodiment 1 of the present invention. FIG. 1 (a) shows an extended state in which the flexible conductor 20 is stretched in the longitudinal direction. FIG. 1B shows a compressed state in which the flexible conductor 20 is compressed in the longitudinal direction. FIG. 2 shows a cross-sectional view when the flexible conductor 20 is connected to an electrical switchgear (switch) while maintaining its mobility, and FIG. 2 (a) shows that the switch is off and flexible. FIG. 2B shows a case where the conductor 20 is not energized, and FIG. 2B shows a case where the switch is on and the flexible conductor 20 is energized. As the metal thin plate 1 constituting the flexible conductor 20, a copper thin plate is mainly used.

By laminating a plurality of strip-shaped thin metal plates 1 and providing joint surfaces 3 at the longitudinal ends by welding, brazing, bolt fastening, etc., the longitudinal ends of the thin metal plates 1 are respectively bundled together with the electrode portions Thus, the integrated flexible conductor 20 is obtained. As shown in FIG. 1, the thin metal plate 1 has a streak-like bent portion 2 (folded portions 2a and 2b in FIG. 2) bent in the width direction, and the bent portion 2 is a metal. The thin plate 1 is formed into a bellows fold structure (bellows structure) that can expand and contract in the longitudinal direction. In addition, the bending process part 2 is formed by press work etc. so that the cross-sectional shape of the longitudinal direction of the metal thin plate 1 may become a mountain shape. Here, for example, the thin metal plate 1 has a structure in which the flat portion and the bending portion 2 are alternately repeated in the longitudinal direction, and the entire length in the longitudinal direction is folded by the formation of the bending portion 2. .
The flexible conductor 20 shown in FIG. 1 is more flexible with respect to mechanical bending than the conventional flexible conductor in which strip-shaped thin metal plates are laminated, because the deformation tolerance due to the bent portions 2a and 2b is added. It has improved.
The metal thin plate 1 does not necessarily need to be made of a single thin plate, and may be configured by forming a thinner plate member in the same shape and stacking a plurality of them.

  Further, in the flexible conductor 20 shown in FIGS. 1 (a) and 1 (b), when two superposed (adjacent) thin metal plates 1 are viewed, a bent portion of the first thin metal plate 1 is seen. 2a and the bending process part 2b of the 2nd metal thin plate 1 become the arrangement | positioning which shifted the position of the longitudinal direction of the flexible conductor 20. FIG. When the positions of the bent portions 2a and 2b are exactly overlapped, the bent portions 2a and 2b are also exactly overlapped and there is no gap between the metal thin plates 1, but by shifting the positions, as shown in FIG. In addition, the mountain-shaped bent portion 2b compressed in the longitudinal direction presses the lower surface (rear surface) of the overlapping metal thin plates 1, and a gap 4 for heat dissipation can be secured between the layers.

  Further, the bent portion 2 b protruding from the upper surface of the flat portion of the thin metal plate 1 is in contact with the lower surface of the flat portion of the other thin metal plate 1 superimposed on the thin metal plate 1. And the protrusion amount of the bending process part 2b which protrudes from the plane part upper surface of the metal thin plate 1 becomes large as the metal thin plate 1 is compressed to a longitudinal direction.

That is, as shown in FIG. 1A, when the flexible conductor 20 is in the extended state, the bent portions 2a and 2b are stretched in the longitudinal direction of the thin metal plate 1, and at the same time, from the flat portion of the thin metal plate 1, Therefore, the gap between the metal thin plates 1 (interlayer) is reduced. On the other hand, as shown in FIG. 1B, in the compressed state in which the flexible conductor 20 is bent as a whole, the bent portions 2a and 2b are compressed in the longitudinal direction, and from the flat portion of the thin metal plate 1 to the mountain shape. Therefore, the gap portion 4 having a dimension capable of securing heat radiation between the overlapping thin metal plates 1 can be formed by extruding the flat portions of the adjacent thin metal plates 1. The gap 4 serves as a ventilation path when the temperature of the flexible conductor 20 rises.
It is known from the fluid analysis results that the dimension of the gap 4, that is, the gap between the overlapping thin metal plates 1 is, for example, about 2 mm.

  FIG. 2 is a cross-sectional view of a switch using the flexible conductor 20 according to the present invention. FIG. 2 (a) is a switch-off state, and the flexible conductor 20 is in a non-energized state. b) is a switch-on state, and shows a case where the flexible conductor 20 is energized. As shown in FIG. 2, in the switch, a movable contact 5 and a fixed contact 6 are arranged to open and close electricity. The fixed contact 6 is fixed to the outside via a fixed electrode rod 7, and the movable contact 5 is attached to the shaft portion 10 a of the drive mechanism 10 via a movable electrode rod 8 and an insulating rod 9. It is possible to switch the switch off state and the on state by the shaft portion 10a of the drive mechanism 10 moving in the left-right direction on the paper surface.

  The movable contact 5, fixed contact 6, fixed electrode rod 7, and movable electrode rod 8 of the switch are all made of a conductor such as copper or aluminum, but the insulating rod 9 is made of an insulator. As shown in FIG. 2 (b), when the switch is on, the current flowing from the fixed electrode bar 7 flows through the fixed contact 6, the movable contact 5, and the movable electrode bar 8 and then through the flexible conductor 20. To take a path to the external fixed terminal 11. Since the insulating rod 9 is interposed, no current flows to the drive mechanism 10 side.

  Further, as shown in FIG. 2B, the flexible conductor 20 is attached to the switch so that the bent portion 2 is compressed when the switch is on and the gap 4 is formed between the thin metal plates 1. ing. In the open / closed ON state, Joule heat is generated in the energization path. However, in the flexible conductor 20 of the present invention, heat flows efficiently from the laminated metal thin plate 1 to the gap portion 4 when the gas flows through the gap portion 4. Since it can escape, the temperature rise of the metal thin plate 1 can be suppressed. On the other hand, in the conventional flexible conductor in which strip-shaped copper thin plates are laminated, although some gaps are generated between the copper thin plates, the interval is very narrow, and the gas does not flow smoothly through the gaps. The cooling effect was not obtained.

As described above, according to the flexible conductor 20 according to the first embodiment of the present invention, the metal thin plate 1 is provided with the mountain-shaped bent portions 2, 2 a, and 2 b and subjected to bellows processing so as to be stretchable. The heat dissipation effect can be improved by adopting a structure in which the bellows fold structure is compressed and the gap 4 is obtained between the metal thin plates 1 only when the switch in which current flows is turned on. Since the flexible conductor 20 having the bellows fold structure does not need to be provided with a circumferential length difference even if it is arranged to have a bent shape, it is necessary to increase the length of the thin metal plate 1 only on the outer circumferential side as in the prior art. However, an increase in electrical resistance can be suppressed accordingly.
In this way, by forming the bent portions 2, 2a, 2b on the thin metal plate 1, the flexibility that suppresses the increase of the resistance value of the flexible conductor 20, the mechanical flexibility, and the temperature reduction at the time of current application can be achieved. The conductor 20 can be realized.

Embodiment 2. FIG.
Next, a second embodiment of the present invention will be described with reference to FIGS.
FIG. 3 is a cross-sectional view of the flexible conductor 20 in an extended state according to the second embodiment of the present invention. As in the first embodiment, the laminated structure of the thin metal plates 1 provided with the bent portions 2 is provided, but spacers 13 are arranged between the thin metal plates 1 at both ends in the longitudinal direction of the thin metal plate 1 to overlap the thin metal plates 1. It is characterized in that a gap is provided by a spacer 13 between the flat portions. Here, the spacer 13 may be formed of either an insulator or a conductor.

  FIG. 4 is a cross-sectional view showing a compressed state in which the elongated flexible conductor 20 of the second embodiment shown in FIG. 3 is compressed in the longitudinal direction. As shown in FIG. 3 and FIG. 4, the flexible conductor 20 provided with the spacer 13 slides with the adjacent metal thin plate 1 that occurs when the bent portion 2 is compressed as compared with the case where the spacer 13 is not provided. Can be reduced. Thereby, the flexibility at the time of deformation | transformation of the flexible conductor 20 can be improved, and the space | gap part between the metal thin plates 1 can be formed stably. That is, the spacer structure of FIGS. 3 and 4 can further improve the mechanical flexibility and heat dissipation performance of the flexible conductor 20.

FIG. 5 is a view showing a modification of the second embodiment of the present invention, and is a cross-sectional view of the flexible conductor 20 in an expanded state. The spacers 13 shown in FIG. 3 and FIG. 4 described above are made of a member different from the metal thin plate 1. However, in the modification shown in FIG. 5, the overlapping metal thin plates 1 in the flexible conductor 20 are separated from each other. The spacer to be formed is formed by a folded portion 14 which is a folded end portion in the longitudinal direction of the thin metal plate 1. The folded portion 14 is superposed on the flat portion of the thin metal plate 1 and plays the role of a spacer depending on the thickness thereof.
As described above, in the configuration shown in FIG. 5, a member is not newly provided as a spacer, but the folded portion 14 serving as a spacer is formed by folding back at the longitudinal end portion of the thin metal plate 1. The number of parts constituting the conductor 20 can be reduced, and the manufacturing cost can be reduced.

Embodiment 3 FIG.
Next, Embodiment 3 of the present invention will be described with reference to FIG. 6 and FIG.
FIG. 6 is a perspective view of the flexible conductor 20 according to Embodiment 3 of the present invention. As in the first embodiment, the laminated structure of the thin metal plate 1 provided with the mountain-shaped bent portion 2 is shown. In the third embodiment, for example, in the center of the flat portion of the thin metal plate 1, A vent (hole) 15 that penetrates the thin metal plate 1 in the thickness direction is provided. Although FIG. 6 shows an example in which the opening shape of the vent hole 15 is circular, the opening shape of the vent hole 15 may be a polygon such as a quadrangle, or other shapes.

  FIG. 7 is a cross-sectional view showing a ventilation path of the flexible conductor 20 provided with the ventilation hole 15 shown in FIG. For example, in FIG. 7, the mountain-shaped bent portion 2 protrudes downward on the paper surface, and a ventilation path extending from the lower side to the upper side of the paper surface is shown. When the thin metal plates 1 are laminated in the direction of gravity, the convection of the gas flowing through the gaps between the thin metal plates 1 is slightly blocked by the thin metal plate 1 spreading in the horizontal direction. However, by providing the metal plate 1 with the vent hole 15, a gas ventilation path that flows upward while branching through each layer through the vent hole 15 as shown in FIG. 7 is formed. Can be obtained.

  6 and 7 show an example in which the vent 15 is formed in the flat portion of the thin metal plate 1 and the ventilation path branches for each layer. However, the portion other than the flat portion of the thin metal plate 1, that is, the bent portion. It is also possible to form the vent hole 15 in 2. Among them, when the vents 15 formed for the plurality of stacked metal thin plates 1 are arranged so as to overlap each other, the ventilation path can be secured in a straight line in the metal thin plate stacking direction. When the laminating direction is the vertical direction, the airflow is particularly stable, and the heat dissipation effect can be increased.

Embodiment 4 FIG.
Next, Embodiment 4 of the present invention will be described with reference to FIG.
FIG. 8 is a perspective view of the flexible conductor 20 according to Embodiment 4 of the present invention. Similar to the first embodiment, it is a laminated structure of thin metal plates 1a to 1d provided with a mountain-shaped bent portion 2. In the fourth embodiment, with respect to the number of bending portions 2 provided on the thin metal plate 1a located on the inner peripheral side with respect to the bending direction of the flexible conductor 20 which is in a bent state as a whole, It is characterized in that the number of the bent portions 2 formed on the metal thin plate 1b on the outer peripheral side is equal or large. Similarly, the number of the bent portions 2 becomes equal or monotonically increases as the metal thin plates 1c and 1d in the outer peripheral direction are moved, and the bent portions 2 of the innermost metal thin plate 1a and the outermost metal thin plate 1d are bent. Comparing the number, the outermost circumference is larger.

  That is, when the flexible conductor 20 is arranged in a bent state, the outer peripheral side of the flexible conductor 20 is at least one of the thin metal plates 1a-1b, 1b-1c, 1c-1d. The number of the bent portions 2 formed on the thin metal plate 1b (or 1c, 1d) is equal to the number of the bent portions 2 formed on the thin metal plate 1a (or 1b, 1c) on the inner peripheral side of the flexible conductor 20. And the number of the bent portions 2 provided on the metal thin plate on the outer peripheral side rather than the inner peripheral side increases. By setting it as such a structure, the flexible conductor 20 suitable for displacing the outer peripheral side more can be obtained. As described above, it is possible to realize the flexible conductor 20 that bends more flexibly by providing the number of the bent portions 2 with density.

Embodiment 5 FIG.
Next, Embodiment 5 of the present invention will be described with reference to FIG.
FIG. 9 is an enlarged cross-sectional view of a main part of one thin metal plate 1 constituting the flexible conductor 20. In the first embodiment and the like described above, the bent portion 2 formed on the thin metal plate 1 is formed so that the cross-sectional shape in the longitudinal direction of the thin metal plate 1 is a mountain shape (when viewed from the back side). However, in the fifth embodiment, as shown in FIG. 9, the arc-shaped bending portion 21 having the same cross-sectional shape formed in an arc shape is formed as an accordion fold structure. The arc-shaped bending portion 21 protruding from the flat portion of the thin metal plate 1 has the same function as the bending portion 2 described above.

In the example of FIG. 9, an example in which the rising angle of the arc-shaped bending portion 21 from the flat portion of the thin metal plate 1 is steep is shown, but the rising angle has a gentle curve shape. It is also possible to process it.
When the metal thin plate 1 (flexible conductor 20) is stretched in the longitudinal direction, the arc-shaped bending portion 21 is widened in the longitudinal direction, and the protrusion amount is reduced accordingly. Conversely, when the metal thin plate 1 is compressed in the longitudinal direction, the width in the longitudinal direction is reduced, and the amount of protrusion is increased accordingly. It is configured.

In the above-described first to fourth embodiments, the example in which the bent portion 2 having the same shape is formed on one flexible conductor 20 has been described. However, the arc-shaped bent portion 21 may be used in combination. .
Further, the dimensions of the bent portion 2 (arc-shaped bent portion 21) need not be uniform, and the bent portion 2 having several kinds of sizes can be formed in one flexible conductor 20. It goes without saying that it is possible.

  It should be noted that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be appropriately modified or omitted.

1, 1a, 1b, 1c, 1d Metal thin plate, 2, 2a, 2b Bending part, 3 Joint surface part, 4 Gap part, 5 Movable contact, 6 Fixed contact, 7 Fixed electrode bar, 8 Movable electrode bar, 9 Insulating bar DESCRIPTION OF SYMBOLS 10 Drive mechanism, 10a, Shaft part, 11 External fixed terminal, 13 Spacer, 14 Folding part, 15 Vent, 20 Flexible conductor, 21 Arc type bending process part.

Claims (11)

A flexible conductor in which a plurality of strip-shaped thin metal plates are laminated, and both ends in the longitudinal direction of the thin metal plates are respectively bundled as electrode portions,
The thin metal plate has a streak-like bent portion bent in the width direction, and the bent portion is formed to be extendable in the longitudinal direction of the thin metal plate.   The flexible conductor according to claim 1, wherein the bent portion is formed to have a bellows fold structure.   The said bending process part which protruded from the plane part upper surface of the said metal thin plate contact | connects the plane part lower surface of the other said metal thin plate superimposed on the said metal thin plate, The possible of Claim 1 or Claim 2 characterized by the above-mentioned. Flexible conductor.   The protrusion amount of the said bending process part which protrudes from the plane part upper surface of the said metal thin plate becomes large as the said metal thin plate is compressed to a longitudinal direction, The possible of any one of Claim 1 to 3 characterized by the above-mentioned. Flexible conductor.   The flexible conductor according to any one of claims 1 to 4, wherein the bending portion is formed so that a cross-sectional shape in a longitudinal direction is a mountain shape.   The flexible conductor according to any one of claims 1 to 4, wherein the bent portion is formed so that a cross-sectional shape in a longitudinal direction is an arc shape.   The flexible conductor according to any one of claims 1 to 6, wherein a spacer is disposed between the plurality of stacked metal thin plates at an end portion in a longitudinal direction of the metal thin plate.   8. The flexible conductor according to claim 7, wherein the spacer is formed by a folded portion obtained by folding a longitudinal end portion of the metal thin plate, and the folded portion is overlapped with a flat portion of the metal thin plate. .   The flexible conductor according to any one of claims 1 to 8, wherein a hole that penetrates the metal thin plate in a thickness direction is formed in a flat portion of the metal thin plate.   In the case where the flexible conductor composed of a plurality of the laminated metal thin plates is arranged in a bent state, the number of the bent portions formed on the metal thin plate on the outer peripheral side of the flexible conductor is 10. The flexible conductor according to claim 1, wherein the number of the bent portions formed in the metal thin plate on the inner peripheral side of the flexible conductor is larger than the number of the bent portions. The flexible conductor according to any one of claims 1 to 10, wherein the flexible conductor is energized in a state where the bent portion is compressed.