JP5121584B2 - Vacuum circuit breaker - Google Patents

Description

  The present invention relates to a vacuum circuit breaker, and more particularly to a vacuum circuit breaker having an improved main circuit conductor fixing structure.

  As a conventional vacuum circuit breaker, the ceiling plate of the insulating frame has a structure with a protrusion that matches the width of the main circuit conductor, so that the main circuit conductor can be prevented from being laterally shifted, and a plurality of stepped structures are provided. Thus, there is one in which a plurality of main circuit conductors can be attached according to the current carrying capacity (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 7-320610 (page 3, FIG. 3)

  In the conventional vacuum circuit breaker as described above, since the main circuit conductor is prevented from being laterally displaced by the protrusions matching the plate width of the main circuit conductor, only the plate-like main circuit conductor can be fixed. The main circuit conductor of the vacuum circuit breaker varies in shape and size depending on the voltage and current capacity. Regardless of the shape and size of the main circuit conductor, the left and right movement of the main circuit conductor is restricted, and the interphase electromagnetic force It is not possible to prevent lateral displacement with respect to the wire, and if the interphase electromagnetic force acts on the main circuit conductor because the distance between the protrusion and the fixing bolt is short, it is the fixing part between the insulating frame and the main circuit conductor. There was a problem that a large load was applied to the protruding portion of the insulating frame and the fixing bolt, which could cause failure.

  The present invention has been made in order to solve the above-described problems of the prior art, can cope with a plurality of shapes and sizes of the main circuit conductor, and is capable of dealing with the inter-phase electromagnetic force. It aims at providing the vacuum circuit breaker which can prevent the horizontal shift | offset | difference of this. It is another object of the present invention to provide a vacuum circuit breaker that can reduce the load applied to the fixed portion of the main circuit conductor when interphase electromagnetic force is applied.

  A vacuum circuit breaker according to the present invention is connected to a vacuum valve, a first main circuit conductor that is connected to a fixed contact of the vacuum valve, and holds a fixed contact side of the vacuum valve, and a movable contact of the vacuum valve. Insulation having a second main circuit conductor and first and second fixing portions that surround the vacuum valve and hold one end portions of the first main circuit conductor and the second main circuit conductor, respectively. A frame, and at least one of the first and second fixing portions includes a plurality of locking holes having different shapes or sizes, and the corresponding first main circuit conductor or second main circuit conductor The locking holes are selected and used according to the structure of the one end.

  In the present invention, at least one of the fixing portions of the main circuit conductor is formed as a plurality of locking holes having different shapes or sizes, and the structure of the corresponding one end portion of the first main circuit conductor or the second main circuit conductor is used. Since the locking holes are selected and used accordingly, it is possible to cope with multiple shapes and sizes of the main circuit conductors, and to prevent lateral displacement of the main circuit conductors with respect to the interphase electromagnetic force. Can do.

Embodiment 1 FIG.
1-4 is a figure explaining the principal part of the vacuum circuit breaker by Embodiment 1 of this invention, FIG. 1 is side sectional drawing explaining the fixing structure of an insulation frame and a main circuit conductor, FIG. 2 is a figure FIG. 3 is an enlarged sectional view showing the vicinity of the main circuit conductor on the fixed contact side shown in FIG. 1, FIG. 3 is a top view of the insulating frame and the fixing portion of the main circuit conductor shown in FIG. 1, and FIG. It is sectional drawing which expands and shows the vicinity of the main circuit conductor by the side of the movable contact shown. In the figure, a cylindrical vacuum valve 2 constituting a shut-off portion of the vacuum circuit breaker 1 accommodates a fixed contact 2b and a movable contact 2c disposed opposite to each other in the vacuum container 2a, and one end of the vacuum container 2a (see FIG. The fixed conductor 2d connected to the fixed contact 2b is led out from the upper part of the figure, and the movable conductor 2e connected to the movable contact 2c from the other end is led out in the figure below. The vacuum circuit breaker 1 opens and closes the contact by moving the movable conductor 2e up and down through the insulating rod 12 by the power from the operation mechanism 11 and moving the movable contact 2c up and down.

  The vacuum valve 2 is surrounded by an insulating frame 3 on the outer side in the radial direction, and the fixed conductor 2d is fixed on the upper fixed contact side by a bolt 51 inserted from the upper part of the first main circuit conductor 4 having a round bar shape (columnar shape). The first main circuit conductor 4 is fixed to the first main circuit conductor 4 by fastening the first main circuit conductor 4 to a predetermined portion of the insulating frame 3 and the third fixing portion. By fixing to 33, the first main circuit conductor 4 and the insulating frame 3 are fixed. On the other hand, on the movable contact side of the vacuum valve 2, a movable conductor 2e led downward in the figure is connected to a round bar-shaped second main circuit conductor 6 via a flexible conductor 52, and the second main circuit The conductor 6 is fixed to a second fixing part 32 and a fourth fixing part 34 provided in a predetermined part of the insulating frame 3. The second main circuit conductor 6 is provided with an insertion hole (a relief hole) 6a through which the movable conductor 2e is inserted in the axial direction. The movable conductor 2e passes through the insertion hole 6a and is not shown in detail. The operating mechanism 11 is connected to an insulating rod 12 that is driven in the vertical direction in the figure.

  As shown in FIG. 2, the first fixing portion 31 includes a first locking hole 31 a having a round hole shape into which one end portion (the left end portion in FIG. 1) of the first main circuit conductor 4 can be inserted, and It consists of a locking hole having a stepped structure having a round locking second locking hole 31b whose outer diameter is larger than that of the first locking hole 31a. Further, in this example, the second fixing portion 32 has a round hole-shaped first locking hole 32a and a round hole-shaped outer diameter larger than that of the first locking hole 32a in the same manner as the first fixing portion 31. It consists of a locking hole having a stepped structure having a second locking hole 32b, and both the first and second fixing portions 31, 32 are formed integrally with the insulating frame 3 main body. The third and fourth fixing portions 33 and 34 have through holes 33a and 34a formed integrally with the main body of the insulating frame 3 on the opposite side of the first and second fixing portions 31 and 32, respectively. The first and second main circuit conductors 4 and 6 are fixed by means of fixing bolts 53 and 54 which are fasteners inserted through the through holes 33a and 34a, respectively. 34 is fixed.

  An interval L (FIG. 3) between the first fixing portion 31 and the third fixing portion 33 is provided, for example, so as to be larger than the outer diameter of the vacuum valve 2. A vent hole 35 is opened. The distance between the second fixed part 32 and the fourth fixed part 34 on the movable contact side is also formed with a dimension substantially equal to the distance L. Further, in order to facilitate understanding of the invention, the left main portion in FIG. 3 has the first main circuit conductor 4 locked in the second locking hole 31b having a large outer diameter in the first fixing portion 31. In the right portion, the first main circuit conductor 4 has an outer diameter smaller than that on the left side, and the outer diameter of the first fixing portion 31 is smaller than that of the second locking hole 31b. The example locked to the hole 31a is shown in comparison. Since other configurations are the same as those of the conventional apparatus, illustration and description thereof are omitted.

  In the first embodiment configured as described above, the first and second fixing portions 31 and 32 that fix one end portions of the first and second main circuit conductors 4 and 6 to the insulating frame 3 Since the first and second main circuit conductors 4 and 6 have a structure of one end of the second main circuit conductors 4 and 6, that is, constituted by a round hole-shaped locking hole corresponding to the shape and dimensions, the lateral displacement of the first and second main circuit conductors 4 and 6 Not only the displacement in the direction but also the displacement in the radial direction can be securely held, and the lateral displacement of the first and second main circuit conductors 4 and 6 due to the interphase electromagnetic force can be effectively prevented. For this reason, the apparatus can be miniaturized. Moreover, since the locking hole has a stepped structure and a plurality of locking portions are formed, as shown in FIG. 3, for example, the locking holes can be selectively used for main circuit conductors having different outer diameters. The same insulating frame 3 can be used, and the types can be reduced. Note that the number of the locking holes may be three or more.

  Further, the first fixing portion 31 and the fixing bolt 53 of the left insulating frame 3 on the left side of FIG. 1 which are two fixing points of the insulating frame 3 and the first main circuit conductor 4 are used. Since the space | interval L with the fixing | fixed part 33 can be enlarged, when the interphase electromagnetic force acts on the 1st main circuit conductor 4, the load added to the 1st, 3rd fixing | fixed part 31 and 33 is reduced. Further, since the space L between the first fixing portion 31 and the third fixing portion 33 of the insulating frame 3 is increased, the area of the vent 35 provided in the ceiling plate portion of the insulating frame 3 can be increased. Accordingly, a remarkable effect can be obtained such that the heat radiation efficiency is good and the natural cooling effect can be improved. The same effect as that of the first main circuit conductor 4 can be obtained with respect to the fixed portion between the second main circuit conductor 6 and the insulating frame 3.

Embodiment 2. FIG.
5 and 6 are views for explaining the main part of the vacuum circuit breaker according to Embodiment 2 of the present invention, and FIG. 5 is a partial sectional perspective view showing the structure of the first fixing portion provided in the insulating frame. FIG. 6 is a cross-sectional view showing a main part of a vacuum circuit breaker using the first fixed part structure shown in FIG. In the second embodiment, the locking holes constituting the first and second fixing portions are formed by combining a circular shape and a rectangular shape. Since the second fixing portion is the same as the first fixing portion, the first fixing portion will be described below as a representative. In the figure, the first fixing portion 31A includes a first round hole-shaped first locking hole 31a similar to that of the first embodiment, and a second round hole-shaped second outer diameter larger than that of the first locking hole 31a. In addition to the locking holes 31b, a plurality of locking holes (locking portions) having different shapes and sizes in combination with the rectangular third locking holes 31c. The first main circuit conductor 4A is made of a flat plate conductor having a rectangular cross section, and one end (the left end in FIG. 6) is inserted into the third locking hole 31c of the first fixing portion 31A. Thus, one end portion is fixed to the insulating frame 3, and the second main circuit conductor 6 </ b> A is similarly fixed to the insulating frame 3 at one end portion in the second fixing portion 32 </ b> A. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

  In the second embodiment configured as described above, the first and second fixing portions 31A and 32A are formed as locking holes having a combined shape of a circle and a rectangle. In addition to the effect of effectively preventing the lateral shift of the second main circuit conductors 4A and 6A, for example, any of the round bar or columnar main circuit conductor and the flat main circuit conductor shown in FIG. The further effect that it is possible is acquired. A plurality of rectangular locking holes may be provided.

Embodiment 3 FIG.
FIG. 7 is a partially cutaway sectional view showing an essential part of a vacuum circuit breaker according to Embodiment 3 of the present invention. In the figure, the heat radiating fins 7 are fixed in close contact with the vent holes 35 above the vacuum valve 2 in the first main circuit conductor 4A. In addition, although a fixing means is not specifically limited, you may make it use the volt | bolt 51 together. Other configurations are the same as those of the second embodiment shown in FIG.
In the third embodiment configured as described above, the surface area of the first main circuit conductor 4A is increased by providing the first main circuit conductor 4A on the first main circuit conductor 4A in the vent 35 portion of the insulating frame 3. Increased, further improvement of heat dissipation effect can be expected.

  In the first to third embodiments, the case where the first fixed portion 31 on the fixed contact side and the second fixed portion 33 on the movable contact side have the same configuration has been described. The present invention may be applied to only one of them. In addition, various modifications are possible within the spirit of the present invention, such as changing the cross-sectional shape of the main circuit conductor to a shape other than circular or rectangular, or changing the shapes of the third and fourth fixing portions 33 and 34 of the main circuit conductor. Needless to say, it can be changed.

Side surface sectional drawing explaining the fixing structure of the insulation frame which is the principal part of the vacuum circuit breaker by Embodiment 1 of this invention, and a main circuit conductor. Sectional drawing which expands and shows the vicinity of the main circuit conductor by the side of the fixed contact shown by FIG. The top view of the fixing | fixed part of the insulation flame | frame shown in FIG. 1 and the main circuit conductor. Sectional drawing which expands and shows the vicinity of the main circuit conductor by the side of the movable contact shown by FIG. The fragmentary sectional perspective view which shows the structure of the 1st fixing | fixed part provided in the insulation frame which is the principal part of the vacuum circuit breaker by Embodiment 2 of this invention. Sectional drawing which shows the principal part of the vacuum circuit breaker using the 1st fixing | fixed part structure shown by FIG. The partially broken sectional view which shows the principal part of the vacuum circuit breaker concerning Embodiment 3 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Vacuum circuit breaker, 11 Operation mechanism part, 12 Insulating rod, 2 Vacuum valve, 2a Vacuum container, 2b Fixed contact, 2c Movable contact, 2d Fixed conductor, 2e Movable conductor, 3 Insulation frame, 31, 31A 1st fixed part 31a 1st locking hole, 31b 2nd locking hole, 31c 3rd locking hole, 32 2nd fixing | fixed part, 32a 1st locking hole, 32b 2nd locking hole, 33th 3 fixed portion, 33a, 34a through hole, 34 fourth fixed portion, 35 vent, 4, 4A first main circuit conductor, 6, 6A second main circuit conductor, 6a insertion hole, 51 bolt, 52 Flexible conductor, 53, 54 fixing bolt (fastener), L (first fixing portion and third fixing portion) spacing.

Claims (6)

  A first main circuit conductor connected to a fixed contact of the vacuum valve and holding the fixed contact side of the vacuum valve; a second main circuit conductor connected to a movable contact of the vacuum valve; An insulating frame that surrounds the vacuum valve and is provided with first and second fixing portions for holding one end portions of the first main circuit conductor and the second main circuit conductor, respectively. At least one of the second fixing portions is formed of a plurality of locking holes having different shapes or sizes, and the engagement is determined according to the structure of the corresponding one end portion of the first main circuit conductor or the second main circuit conductor. A vacuum circuit breaker characterized in that a blind hole is selected and used.   The vacuum circuit breaker according to claim 1, wherein the locking hole has a plurality of locking portions formed in a stepped structure.   The vacuum circuit breaker according to claim 1 or 2, wherein the locking hole is a hole having a combination of a circle and a rectangle.   The first main circuit conductor is fixed to the insulating frame by a fastener at a third fixing portion opposite to the first fixing portion with respect to a portion holding the fixed contact side of the vacuum valve. The second main circuit conductor is fixed to the insulating frame by a fastener at a fourth fixing portion opposite to the second fixing portion with respect to a portion passing through the movable contact side of the vacuum valve. The vacuum circuit breaker according to any one of claims 1 to 3, wherein the vacuum circuit breaker is provided.   The vacuum circuit breaker according to any one of claims 1 to 4, wherein a vent is provided above the vacuum valve in the insulating frame.   6. The vacuum circuit breaker according to claim 5, wherein a radiation fin is provided on the first main circuit conductor disposed so as to cross the vicinity of the vent hole.

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