JPH087722A - Gas-blast circuit breaker - Google Patents

Abstract

PURPOSE:To reduce sliding resistance of a slide part of a movable contacting piece, decrease the load on a contacting part, and provide a small gas-blast circuit breaker at a low cost by constructing the movable contacting piece consolidatedly by means of fastening to an insulative arm or the like, and allowing it to make an orbiting motion round the main shaft. CONSTITUTION:Together with an insulative gas such as SF6 gas, an encapsulation case 15 accommodates a tulip-form stationary contacting part consisting of a plurality of stationary contacting pieces 2 installed inside a rotary arc- extinguishing chamber 4 and a rod-shaped movable contacting piece 1 arranged opposing to the stationary contacting part. A rotational drive means (for example, a means using the drive force given by a turnon magnet or a break spring) turns on or opens the movable contacting piece 1 to/from the stationary contacting piece wherein the rotational motion takes place with the main shaft 9 installed in the case 15 as the fulcrum. According to this constitution, any guide rod or guide frame is no more needed to lead to elimination of the sliding resistance to be generated when the movable contacting piece is in motion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas circuit breaker, and more particularly to a contact portion structure thereof.

[0002]

2. Description of the Related Art Conventionally, in a circuit breaker having a tulip-shaped contactor in which three or more fixed contactors (pieces) are combined in a cylindrical shape, and a round-bar-shaped movable contactor arranged to face the tulip-shaped contactor, a movable contactor is used. As a driving method of the child, for example, as shown in FIG. 3, the inside of the movable contactor 1 is made hollow, a guide rod 50 is provided in the hollow portion, and the movable contactor 1 is slid by using it as a guide. Movable contact 1 as shown
A method has been adopted in which a guide frame 53 is provided on the outer periphery of and the movable contact 1 is slid with the guide frame 53 as a guide.

However, in the tulip-shaped contactor that has been adopted up to now, the movable contactor 1 has a linear movement, and since it is a slide system as shown in FIGS. Since the sliding resistance between the guide rod 50 and the guide rod 50 and the sliding resistance between the guide rod 50 and the current collector contact 51 slows down the operation speed and makes the closing time and the closing time longer, the loss is caused by the magnet generated. The magnetic force must be increased and the tripping load of the breaking spring must be increased, resulting in a large circuit breaker.

In the contactor structure adopted in the conventional circuit breaker, as a small capacity one, the contact of the movable contactor 1 is vertically contacted with and separated from the contact of the fixed contactor 2 shown in FIG. There is a butt contact for rotating the movable contact 1 around the central axis 9a of the main shaft 9. However, for this butt contact method, although there is no problem with a small capacity circuit breaker,
If it is a medium-capacity or large-capacity circuit breaker, it cannot be used because it has a small number of contact points and it increases in size by increasing the number of contact points. A contact is often used.

In FIGS. 3 to 5, reference numeral 3 is a fixed contact table 5
Is a contact spring, 8 is a power source side bushing, 11 is a flexible conductor, 15 is a gas filled case, 31 is a load side bushing, and 53 is a guide frame.

[0006]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is to reduce the sliding resistance of the sliding part of the movable contactor and to reduce the load on the contact part, thereby providing a compact and low-cost circuit breaker. To provide.

[0007]

In order to solve the above-mentioned problems, a gas circuit breaker according to the present invention is provided with a plurality of gas circuit breakers arranged in a rotary arc type arc extinguishing chamber together with an insulating gas such as SF ₆ gas in a sealed case. A tulip-shaped fixed contact portion composed of a fixed contact element and a rod-shaped movable contact element that is arranged so as to face the fixed contact element, and the movable contact element is a fulcrum with the main shaft provided in the enclosure case as a fulcrum. A rotary drive means is provided for closing and opening the fixed contact portion.

[0008]

In the present invention, the movable contactor is integrated with the insulating arm by a method such as tightening, and a circumferential movement around the main shaft is performed, thereby eliminating the need for a guide rod. Therefore, the sliding resistance between the movable contact and the guide rod and the sliding resistance between the guide rod and the current collecting contact are eliminated, so that the operation speed is increased. Therefore, it is possible to downsize the shape by reducing the magnetomotive force of the closing magnet, and downsize the spring by reducing the trip load of the blocking spring.
A small-sized and low-cost circuit breaker can be provided.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the embodiments shown in the drawings.

FIG. 1 is a partial vertical sectional view of a gas circuit breaker embodying the present invention, and FIG. 2 is a vertical sectional view of an operating portion of a movable contactor, which is an essential part of the present invention. In FIG. 1, 1 is a movable contactor, 2 is a fixed contactor, 3 is a fixed contactor base, 4 is an arc extinguishing chamber, 5 is a contact spring, 6 and 14 are airtight flanges, and 7 and 1.
3 is a conductive rod, 8 is a power source side bushing, 9 is a main shaft, 10 is an insulating arm, 11 is a flexible conductor, 12 is a nut, 15 is a gas filled case, 16 to 20 are O-rings, and 21 and 23 are hexagonal holes. Bolts, 22, 24, 26 and 29 are spring washers, 25 and 28 are hexagon bolts, 27 and 30 are plain washers, and 31 is a load side bushing.

Next, the operation of the above-structured one will be described.

First, the movable contact 1 is fitted into the through hole 10a of the insulating arm 10 and is tightened with the nut 12. The insulating arm 10 is directly fastened to the attachment plate 9b attached to the main shaft 9 by welding or the like with the hexagon socket head cap screw 23 and the spring washer 24. On the other hand, the flexible conductor 11 is directly fastened to the end of the movable contactor 1 with the bolt 25, the spring washer 26, and the flat washer 27.
The other end of the flexible conductor 11 is directly fastened to the conductive rod 13 with a bolt 28, a spring washer 29, and a flat washer 30. Here, at the time of the closing operation, the main shaft 9 is rotated counterclockwise about the central shaft 9a by the driving force from the closing magnet (not shown). By the rotation of the main shaft 9, the movable contact 1 is driven via the insulating arm 10 to reach the cylindrical fixed contact portion composed of three or more fixed contacts 2 arranged in the arc extinguishing chamber 4. Is fitted with. Next, at the time of the breaking operation, the main shaft 9 is rotated clockwise around the central shaft 9a by the driving force from the breaking spring (not shown), and the movable contact 1 is separated from the fixed contact 2.

[0013]

As described above, according to the present invention, the movement of the movable contactor is a circumferential movement around the main shaft, so that the guide rod or the guide frame is not required and the movable contactor is operated. The sliding resistance of can be eliminated. For this reason,
Since it is not necessary to make the closing magnet and the breaking spring stronger than necessary, a compact and low-cost gas circuit breaker can be obtained.

[Brief description of drawings]

FIG. 1 is a partial vertical cross-sectional view of a gas circuit breaker embodying the present invention.

FIG. 2 is a vertical cross-sectional view of a movable contactor operation portion of a main part of the embodiment of the present invention.

FIG. 3 is a vertical cross-sectional view of an operating portion of a conventional linear slide system in which a guide bar is provided inside a movable contact.

FIG. 4 is a vertical cross-sectional view of an operating portion of a conventional linear slide system in which a guide frame is provided on the outer circumference of a movable contact.

FIG. 5 is a vertical cross-sectional view of a conventional gas circuit breaker having a butt contact type contact portion.

[Explanation of symbols]

1 movable contactor, 2 fixed contactor, 3 fixed contactor base, 4 arc-extinguishing chamber, 5 contact spring, 6,14 airtight flange, 7,13 conductive rod, 8 power supply side bushing, 9 spindle, 10 insulating arm , 11 flexible conductors, 1
2 nuts, 15 gas-filled case, 16-20 O-ring, 21,23 Hexagon socket head cap bolt, 22, 24, 2
6,29 Spring washer, 25,28 Hexagon bolt, 27,30 Plain washer, 31 Load side bushing, 50
Guide rod, 51 current collecting contact, 52 current collecting spring,
53 Guide frame

Claims (1)

[Claims] 1. A tulip-shaped fixed contact comprising a plurality of fixed contacts (2) arranged inside a rotating arc-type arc extinguishing chamber (4) together with an insulating gas such as SF ₆ gas in a sealed case (15). And a rod-shaped movable contactor (1) arranged so as to face the fixed contacting portion, and the movable contactor (1) is connected to the main shaft (9) provided in the enclosure case (15). A gas circuit breaker, characterized in that, as a fulcrum, it is provided with a rotation driving means for closing and opening the fixed contact portion.