SK278871B6 - Gas insulated switch gear - Google Patents

Abstract

The switching device, encapsulated a filled with the use of isolating gas, sulphur hexa-fluoride especially, has a rigid contact (2) fixed to connecting bar (10), together with quenching mechanism (11), while this connecting bar is passing through the gas vessel (1) and it is fixed on the supports (13) in a parallel direction with a front part of the gas vessel (1). The movable contact (3) is created like a knife touching the fixed contact (2) of both sides and it is touching of the eart hing contact (4) simultaneously. The pin (5) creating the rotary axis closed to the movable contact (3) is connected with the terminal (15) located at the front part of the gas box (1). The terminal (15) is closed via the wheel plug (16) from outside and the cable (19) is terminated in this plug. The switching equipment may be applied in the middle voltage networks especially, where a space is limited a lot, in distributing centres, as for instance.

Description

Technical field

The invention relates to a gas-filled encapsulated switchgear with a box filled with sulfur hexafluoride, with at least one fixed and one movable contact, an arc quenching mechanism, a busbar and a bushing for a socket connection.

BACKGROUND OF THE INVENTION

In medium-voltage distribution systems, switch-disconnector devices are used practically everywhere. The preferred embodiment of the so-called circular networks allows the use of a large number of switch-disconnectors in network stations. Due to the small and expensive space in the cities, disconnector devices with a large amount of insulating material have been conceived. However, in a country of unfavorable climate of network stations with high temperature fluctuations, high air humidity and the resulting moisture build-up, these devices present difficulties which can only be remedied by additional measures. The demands of the users therefore required not only a reduction of these devices, but also greater reliability. Instead of the insulator, sulfur hexafluoride SF ₆ was used as the insulating gas, while the encapsulation, reliably resistant to pressure and gas leakage, ensures a constant amount and quality of the insulating gas.

A switching device of this kind is known from German patent application DE 27 29 57 1. In this case, the individual switches are arranged in metal cabinets and each switch-disconnector has a movable contact in the form of a switching pin, a quenching mechanism and a special grounding switch. The extinguishing mechanism consists of a gas-tight and pressure-tight encapsulated extinguishing chamber, preferably filled with pressurized gas. The busbars used for supplying the electric power are arranged in a busbar housing separated from the metal housing. This causes a separate seal to be provided between each metal box and the busbar box.

The purpose of the invention is to reduce the number of components of a switching device of the kind mentioned and to arrange the components so that the switching device has small dimensions and a limited depth.

SUMMARY OF THE INVENTION

SUMMARY OF THE INVENTION The fixed contact, together with the quenching mechanism, is mounted on a busbar mounted firmly on the gas box supports parallel to its front face and the movable contact is formed as a knife for connecting the fixed contact and the ground contact. it is connected to a grommet on the front of the gas box and the grommet is closed externally by a knee plug containing the end of the cable.

The advantage of such a construction is its space saving, cheap production price and minimal maintenance. This is mainly due to the fact that the busbars are fitted in a gas cabinet. An economical use of the narrow space available is also supported by a knee plug with a cable attached.

According to the invention, the movable contact is movable between a switch position and a grounding position, so that it can also be used for a grounding mechanism; this eliminates the need for additional blocking between the power switch and the earthing mechanism.

The use of cooling sheets embedded stepped between parallel walls connected to one another allows a considerable reduction in the arc quenching mechanism, and has the further advantage that the arc quenching mechanism is relatively simple to manufacture.

BRIEF DESCRIPTION OF THE DRAWINGS

An example of a switching device according to the invention is shown in the drawing showing a cutaway side view of the switching device.

DETAILED DESCRIPTION OF THE INVENTION

Several switch-disconnectors having the same construction are arranged in the gas tank 1. Thus, the illustrated embodiment and the following description are limited to one switch. The switch-disconnector consists of a fixed contact 2, a movable contact 3 and a ground contact 4. The fixed contact 2 is fixed to the busbar 10, while the movable contact 3 together with the lever 6 is mounted on the pivot axis 5 forming the pivot axis. the contact 3 is formed so that it contacts either the fixed contact 2 or the ground contact 4 from both sides. The lever 6 is connected by a drawbar 7 with a lever 9 mounted on a switching shaft 8. The busbar 10 is mounted on supports 13 which are fastenings 14 The busbar 10 is parallel to the two longitudinal sides of the gas tank 1 and, in close proximity to the fixed contact 3, carries an arc-extinguishing mechanism 11. The arc-extinguishing mechanism 11 consists of two walls into which the cooling plates 12 are inserted. In the bushing 15 is inserted a knee plug 16, closed by the end of the cables 19. The inside of the cable plug 16 is a contact pin 17 which fits into the corresponding bushing of the bushing 15. The cable lug 18 surrounds the conductor at the end of the cable 19 and forms its connection with the contact pin 17. The nut 20 serves to fasten and press the cable lug 18 the contact pin 17. The nut 20 is accessible through the opening 21 in the elbow plug 16 with a closable cap 22.

Claims (5)

1. Encapsulated gas-filled switchgear, with a box filled with sulfur hexafluoride, with at least one fixed and one movable contact, with an arc quenching mechanism, a busbar and a socket connection, characterized in that the fixed contact (2) is together with the arc quenching mechanism (11) mounted on a busbar (10) mounted firmly on supports (13) in the gas cabinet (1) parallel to its front face, and the movable contact (3) is formed as a knife contacting the two-sided fixed contact (2) and the ground contact (4), the pivot axis of the movable contact (3) is connected to the bushing (15) on the front side of the gas box (1) and the bushing (15) is closed externally by a knee plug (16) containing the cable end (19). Encapsulated switchgear according to claim 1, characterized in that the movable contact (3) is fixedly connected to the tape (6) and has, together with it, a common pivot axis formed by the pin (5), the free end of the pin 2 being connected. The bolts (6) are articulated on a drawbar (7) which is connected to the switching shaft (8) by means of a further lever (9). Encapsulated switchgear according to claim 1 or 2, characterized in that the movable contact (3) is mounted rotatable between a switch-on position, a grounding position and a switch-off position. Encapsulated switchgear according to claims 1 to 3, characterized in that the arc quenching mechanism (11) consists of two parallel walls connected to one another in which the cooling plates (12) are mounted in a staircase. Encapsulated switchgear according to one of Claims 1 to 4, characterized in that the elbow plug (16) comprises a contact pin (17) connected to the press-on lug (18) of the end of the exit cable (19), the attachment of the cable lug (17) is accessible by an opening (21) which can be closed from the outside by a cap (22).