DE837721C - AC switch with arc extinguishing by flowing pressurized gas - Google Patents

Description

(WiGBL p. 175)

ISSUED MAY 2, 1952

B 8152 VUIb 121 c

Pressurized gas

The invention relates to electric circuit breakers provided with gas blowers for alternating current operation, especially at high voltage. Its purpose is to operate such breakers the use of compromised gas and at the same time by inducing lxisscrcr To effectively improve interruption characteristics at high voltages. One already has proposed to equip a breaker with gas blowing device with two contact nozzles, through which the arc-quenching gas flow goes in opposite directions in such a way, that the gas flows through one of the contacts into a space which is in communication with the atmosphere stands and through the other contact in a completely closed chamber, in the front of the Separation of the contacts there is a pressure that does not significantly exceed atmospheric pressure. After its supply has been interrupted, the gas flows from this chamber through the two hollow ao Contacts back into the atmosphere.

The present invention seeks to provide an improved construction of a gas blower breaker of the type explained above, which are particularly suitable for use in as high voltages and strong currents.

A gas bubble interrupter in accordance with the present invention consists of a housing, one within of the housing attached chamber, which on their opposing walls a

Pair of fixed hollow contacts, further comprising a pair of movable hollow contacts so arranged are that each of them works together with one of the fixed contacts, and that each other can be separated from the same in opposite directions in such a way that they are two connected in series Forming interruption points within the housing, the movable contacts by the gas pressure supplied to the housing

ίο will, from their respective permanent contacts be driven and thus be separated from them. According to the invention, the arrangement is such that that the pressurized gas borrowed after separation of the contact pairs in the hollow moving Contacts flows, escapes through them into the atmosphere and at the same time the Chamber flows through to generate a pressure here, whereupon the trapped inside the chamber Gas after the supply line of the pressure -

ao gases to the housing is interrupted, escapes to the atmosphere through the two contact pairs, so that in this way a second gas surge is generated between the contacts.

The drawing illustrates in section the

a $ formation of a gas blower circulation interrupter in a construction according to the invention.

In the embodiment shown, two pairs of contacts 10, 11 and 12, 13 which can move relative to one another are used. The contacts are connected to one another in such a way that they form two series-connected interruptions in the circuit to be controlled. The contacts of the circuit breaker are enclosed in an outer cylinder 16 made of insulating material which forms a rigid housing against which the movement of a contact 11, 13 of each pair of the relatively mutually movable contacts takes place. The other contacts 10, 12 are fixed in their position with respect to the outer housing. The housing carries a closed chamber 17 in a rigid connection, in the opposing walls of which the fixed contacts are attached. The chamber 17 is between two insulating strips I4 _1; IS ₁ carried, a clear distance between the wall of the chamber 17 and the inner circumference of the fixed housing 16 is left for the passage of pressurized gas. The movable contacts 11, 13, which cooperate with the fixed contacts, are designed in the form of hollow movable pistons which are attached to the cylinders 20,22 surrounding them, which in turn are fixedly arranged within the outer housing 16 and at a distance therefrom. All contacts are in the form of nozzles. The fixed contacts are provided with mouths 18 which lead into the interior of the housing 17, while the movable contacts have mouths 19 which guide the pressurized gas in such a way that the passages leading to the atmosphere are sucked out. The movable contacts are brought into engagement with the fixed contacts by springs 25. In this position, the openings in the contact pairs, which are closed for the flow of the compressed gas, are shown in dashed lines.

In operation, pressurized gas is through the passage 28 into the space within the outer housing supplied. The same flows behind the outer wall of the cylinder 17 and pushes against the surfaces of the moving contacts. These are, as shown, designed so that they larger diameters than the fixed contacts, which enables the pressure to make them effective operate and the movement of the movable contacts against the pressure of the springs 2 5, from the fixed contacts away, to facilitate. The outer housing rests with its lower end on one Pedestal or the like made of suitable insulating material. End clamps 26, 27 are arranged here, to establish the connection to the moving contacts.

When supplying compressed gas to the interior of the housing 16, the movable contacts of the fixed contacts pushed into the position illustrated in the drawing. The gas flows through the openings in the movable contacts to the atmosphere. At the same time the gas flows through the opening 18 in the fixed contacts to the inside of the closed chamber 17, in which it generates a pressure which eventually increases to the value at which the gas velocity through the openings 18 below, the critical value sinks. The period of time for the gas to flow through the openings at critical velocity 18 in the closed chamber is determined by the volume of the closed chamber, the cross section the openings 18 leading into the chamber and the pressure of the gas used are determined. The time period is expediently of the same order of magnitude as five half cycles of alternating current.

After the pole of light has been extinguished and the supply of compressed gas has been interrupted, it flows the compressed gas led back into the chamber 17 and generates a gas flow in the opposite direction Direction through> the openings 18 to continue through the openings 19 to flow out.

In dashed lines, a tilt valve 26 is illustrated, which can be used in the Chamber 17 accelerated release of stored pressure upon termination of a power interruption, to facilitate reclosing of the breaker. The valve 26 can when the Pressure in the chamber 17 is closed and when the pressure in the chamber 17 drops at the end opened after the power interruption.

Because the contacts close again as soon as the ■ supply of pressurized gas to the housing is interrupted is and the gas pressure within the chamber 17 decreases, it is necessary in series iao circuit with the breaker to use an isolating switch that is automatically activated by the in pressure developed in the chamber 17 as soon as the circuit breaker is open. Usually if the breaker has to be closed, the contacts are closed by

lead of pressurized gas to the housing opened, wherein the isolating switch is closed and the supply of pressurized gas is interrupted to allow the contacts to close. This process can be carried out automatically. If it is necessary to close again immediately, the automatic opening of the isolator, as explained above, prevented.

Claims (2)

Patent claims: i. AC switch with arc extinguishing by flowing pressurized gas, with a housing and a chamber fixedly attached within the housing, to the opposite walls a pair of solid hollow contacts is provided while a Pair of movable hollow contacts is arranged so that each of them with one of the fixed Contacts working together, with the moving contacts separated from the fixed contacts in opposite directions are separated, so that two interruption points connected in series are formed within the housing, and the movable contacts by the pressure of the supplied to the housing Gases driven from their respective fixed contacts and so separated from them are characterized by such an arrangement that the compressed gas after separation of the contact pairs is guided into the hollow movable contacts and through the same escapes to the atmosphere while flowing into and into the chamber at the same time a pressure is generated, whereupon the gas trapped in the chamber after the interruption of the Pressurized gas supply to the housing escapes through the two pairs of contacts into the atmosphere, so that a second gas blast is generated between the contacts. 2. AC switch according to claim 1, characterized in that a device is provided is accelerated to the increased gas pressure in the chamber after the power interruption drain, which makes reclosing the breaker easier. 1 sheet of drawings O 5137 4.