US2573256A - Arrangement in rapid reclosing compressed air circuit breakers - Google Patents

Description

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ARRANGEMENT IN RAPID RECLOSING COMPRESSED AIR CIRCUT BREAKERS Filed Jan. 17, 1948 Patented Oct. 30, 1951 ARRANGEMENT IN RAPID Riser-losing ooM- PREssED AIR CIRCUITA BREAKERS Haakon Forwald; Valhalla, Ludvika, Sweden, as'- signor to Allmanna SvenskaElektris'ka Aktiebolaget, Vasteas, Sweden, a' Swedish corporation Application January 17, 194s, serial No. 2,915 In Sweden .uly 17, 1943 Section 1, Public Law 690, August 8, 1946' Patent expires July 17, 1963 3 Claims.

In compressed air circuit breakers with rapid reclcsing it is often not necessary at occurring faults to interrupt all phases, it generally being suicient to interrupt the phase, where the fault occurs, whereas if the fault remains, all phases are interrupted.

The present invention has for its object such a rapid reclcsing circuit breaker separately interrupting the phases and is characterized thereby that when a breaking impulse arrives all extinguishing chambers are immediately lled With compressed air. At the first interruption, only the faulty phase is opened, but if the fault after reclcsing remains, all breaking gaps are opened. The arrangement is combined with the advantage that at the denite interruption all breaking chambers are lled with compressed air ready to perform the extinction. After fullled interruption and after opening of the disconnecting switches connected in series with the breaking gaps the extinguishing chambers are emptied and their contacts returned to the closed position. The valve controlling the extinguishing air can either be common for all phases or a separate valve may be arranged for each phase.

On the accompanying drawing, one form of the invention is shown in a cross-sectional view with a separate air valve for each extinguishing chamber. The left-hand phase is illustrated in open position, the corresponding controlling contacts 8 being closed, while the middle and the right-hand phases are shown in closed position with their controlling contacts 8 in open position. The compressed air is delivered to the extinguishing chambers I from the containers 2 through the air valves 3 which are opened by means of the air valves 9, when, by closing of the contact 5, the operating coils 4 of the valves 9 are energized. The contacts 5 are closed by the actuating coil I0, which is energized When a fault occurs or when the circuit breaker otherwise should be open. After the extinguishing chambers I have been lled With compressed air, the interruption is eiected by delivery of compressed air to the dilerent operating pistons I I through the valves '6, which are open when the contacts 8 are closed, so that the coils 'I become energized. This can be done either in one or in a plurality of phases, so that the contacts I2 are separated either in one or in a plurality of extinguishing chambers I.

Upon reclosure, the contacts 8 which have been closed are opened again, so that the breaking gap in the corresponding extinguishing chamber is closed again. Obviously, none of the contacts 2 8 can energize the coils 1 prior to the closing of contacts 5.

If the disturbance remains after the reclosure, the contacts I2 in all extinguishing chambers I generally are opened, the arrangement being such that then all contacts 8 are closed. After the disconnecting switch not shown in the drawing but coupled in series with the circuit breaker has been opened, the contact 5 and all contacts 8 are opened again, so that the extinguishing chambers i are emptied from compressed air and so that the contacts I2 therein are again closed.

In the operation of this circuit-breaker, the contacts I 2 of one or more of the phases are opened by the delivery of compressed air through valves 6 to the corresponding piston or pistons II, but the arrangement is such that actuation of these pistons to open the contacts I2 is not possible until the contacts 5 have been closed and compressed air has thus been caused to pass from the containers 2 to the chambers I of all of the phases, so that opening of the contacts I2 before compressed air is available in the arcing chambers is prevented. If the fault persists after the closing of the contacts I2 that have been openened, the contacts I2 in all phases are then opened by the closing of the contacts 8. For the subsequent reclcsing of the contacts I2, it is necessary only to simpltaneously open all the contacts 8, so that the air pressure above the pistons II is relieved and the contacts I2 are all closed simultaneously.

I claim as my invention:

l. A rapid reclcsing multi-phase air blast circult breaker, comprising air blast extinguishing chambers, breaker contacts in said chambers, means for the simultaneous control of the delivery of extinguishing air to said chambers of all the phases, means for the individual control of the breaker contacts in each phase independently of the contacts in the other phases, and means whereby the opening of any of the breaker contacts is prevented until compressed air has rst been delivered to said extinguishing chambers.

2. A rapid reclcsing multi-phase air blast circuit breaker, comprising air blast extinguishing chambers, breaker contacts in said chambers, an electrically operated air blast control valve for the admission of air to said chambers individually for each phase, an electrically operated air valve for the individual operation of the breaker contacts of each phase, common operating contacts for all said air blast control valves, individual operating contacts for each breaker contact operating air valve, said individual contacts permitting 5 individual opening of the breaker contacts, and electrical connections whereby operating current is fed to said individual operating contacts only when said common operatingvcontacts are closed.

3. A rapid reclosing multi-plase air blast circuit breaker, comprising air blast extinguishing chambers, breaker contacts in said chambers, an electric switch for the simultaneous control of the delivery of extinguishing air to the said chambers of all the phases, an individual switch for the control of the operation of the contacts in each phase, electrical connections feeding electric current to all said switches and preventing the passage of current through said individual l5 switches and the opening of said breaker contacts before the closing of the 'rst mentioned 4 switch and the delivery of compressed air to the chambers.

- HAAKON FORWALD.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS

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