JPS60258817A - Vacuum breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a circuit breaker, and particularly to an improvement of an operating box that also serves as a holding structure for a circuit breaker.

[Background of the invention]

In general, small circuit breakers such as vacuum circuit breakers are constructed with an operating device on the front and a cut-off section on the back.
There is one with an operating device on the bottom and a shutoff part on the top. Among these, those with the operating device located on the front have the advantage of making maintenance and inspection easier as the inside of the operating mechanism is easy to see and handle. Because of the layout of the circuit breaker, the depth of the circuit breaker as a whole is large, and the installation area and the distribution board that houses the circuit breaker are also large. This tendency becomes more pronounced as the voltage increases, since a longer electrical insulation distance is required.

FIG. 1 is a side sectional view of a conventional structure in which this defect has been partially improved. In this figure, reference numeral 1 denotes an insulating support frame made of epoxy resin, polyester resin, or the like, and is fixed to the operating device box 2 with bolts or the like. The conductor 5 connected to the fixed electrode 4 of the vacuum pulp 3 is arranged on the upper part of the insulating support frame 1. On the other hand, at the lower part of the insulating support frame 1, a lower conductor 8 is arranged which is connected via a collector 7 to a movable electrode 6 which is disposed opposite to the lower part of the fixed electrode. The lower end is connected to the insulated operating rod 9, and the main lever lO1
It is connected to an operating mechanism 12 via an operating rod 11 . FIG. 2 shows a cross section taken along the line ■-■ in FIG. 1, and the controller box 2 generally includes a back plate 13, a right side plate 14, and
It is formed into a rectangular shape by a left side plate 15 and a front cover 16 attached with bolts or the like.

In the above configuration, the conductor 5, fixed electrode 4, movable electrode 6, lower conductor 8, etc. are parts to which high voltage is applied, and the controller box 2 is a grounded metal. Electrical insulation between these parts is maintained by the creeping insulation of the insulation support frame 1, the insulation operating rod 9, and the air insulation of the space.

Since the back plate 13 of the controller box 2 shown in FIG. 1 has a spatial distance extended by 11 dimensions as shown in the figure compared to a straight case, it is advantageous in terms of electrical insulation, but if tI is increased, Since the dimensions 42 of the side plates 14 and 15 are reduced accordingly, the side plates must be reinforced by making them thicker or by attaching reinforcing materials, which increases the weight and the price. Further, since the corner portion 41 of the operating device box 2 shown in FIG. 2 is welded, etc., it is difficult to form a large smooth roundness, and the electric field tends to concentrate thereon. Therefore, there was a drawback that the electrical insulation effect was not very large.

[Purpose of the invention]

The purpose of the present invention is to maintain strength without increasing weight, and
To provide an operator box structure which prevents concentration of electric field, stabilizes electrical insulation, and reduces the depth of a circuit breaker.

[Summary of the invention]

The key point of the present invention is to partially bend the end surfaces of both side plates of the operating device box into a U-shape to increase strength, and to increase the roundness of the bent portions to alleviate the electric field.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 3 and 4.

In the present invention, the operator box 17 and the insulating support frame 18 are improved. The configuration of the controller box 17 is as shown in FIG.
Bend only the lower side of the ends of the side plates 19 and 20 on the side of the insulating support frame into a U-shape inside the operating box. The larger the roundness of the bent portion, the more effective the electric field will be relaxed. Further, the back plate may have an integral shape, but it can also be divided into two parts, an upper part and a lower part, as shown in FIG. Since the side plates are bent into a U-shape to increase their strength, the back plate 21 attached to that part can be made thinner and the weight can be reduced. Then, only the 22 portions to which the insulating support frame 18 is attached need to have the same thickness as the conventional one. On the other hand, the upper end surface of the operating device box is configured to be lower than the height of the upper conductor 5 so that the electrical insulation strength between it and the upper conductive part is equal to the insulation strength of the lower part. Therefore, the mounting ears 19 of the insulating support frame 18 to the operating device box 17 are also configured to be lower than the height of the upper conductor 5.

With this configuration, the back plate is attached to the U-shaped lower part of the side plate to form a mouth-shaped part, so the strength can be increased even if the dimension 43 shown in FIG. 3 is reduced. Therefore, conversely, it is also possible to make the side plates thinner. Similarly, as mentioned above, the lower portion of the backing plate can be made thinner. In addition, since the part with the shortest spatial insulation distance shown in Figure 3 is formed with a large roundness on the operation box side, the electric field is relaxed, the insulation strength is increased, and the depth of the insulation support frame is reduced. This allows the depth of the circuit breaker to be reduced.

〔Effect of the invention〕

According to the present invention, it is possible to strengthen the mechanical and electrical insulation, so the depth of the circuit breaker and the power distribution board to be housed can be reduced.
Furthermore, the weight can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a vacuum circuit breaker with a conventional structure, FIG. 2 is a sectional view taken along arrows -■ in FIG. 1, FIG. 3 is a side sectional view of a vacuum circuit breaker of the present invention, and FIG. 3 is a sectional view taken along the line ■-■ in FIG. 3; FIG. 17... Controller box, 18... Insulating support frame. Agent Patent Attorney Akio Takahashi 1゜7 (7) Condolences] Figure 97-

Claims (1)

[Claims] 1. An operating box disposed on the front and containing an operating mechanism, an insulating support frame disposed on the back thereof, a vacuum valve housed within the insulating support frame, and upper and lower In a vacuum circuit breaker consisting of a conductor and an insulated operation iron, the depth of the portion of the adjacent operation box disposed opposite to the lower end surface of the insulated support frame is greater than the depth of the mounting portion of the insulated support frame. A vacuum circuit breaker characterized by being small in size and configured by rounding the ends of both side plates of this small depth part and bending them into a U-shape. 2. The vacuum circuit breaker according to claim 1, characterized in that a back plate is attached to each of the U-shaped side plate portions so as to form an opening shape. 3.% Permissible The vacuum circuit breaker according to claim 1, wherein the height of the operator box is lower than the height of the upper conductor.