GB388125A - Improvements in and relating to gas-blast electric switches - Google Patents

Abstract

388,125. High-tension switches. INTERNATIONAL GENERAL ELECTRIC CO., Inc., 120, Broadway, New York, U.S.A.-(Assignees of Allgemeine Elektrici. tõts.Ges.; 2, Friedrich Karl-Ufer, Berlin.) Nov. 6, 1931, No. 30828. Convention date, Nov. 6, 1930. [Class 38 (v).] Relates to a gas-blast switch with circuitbreaking contacts (for example 5 .. 8) in series with one another and with isolating contacts 3 at which no current is interrupted, the arrangement being such that when the breaker has been isolated from the current by the opening of the isolating contacts the break contacts automatically close, as in Specification 378,377. According to the invention, the opening of the isolating contacts is effected through the medium of the compressed gas which fills a cylinder or charges a spring ready for the closing movement while the blow-out blast is in action and is effective to do the further work after the gas blast supply has been cut out, thereby economizing gas pressure. In the arrangement shown, when the gas pressure is turned on it enters through the non-return valves 9 .. 12 and withdraws the contact pins from their nozzle contacts 5.. 8 against the action of springs. The gas escapes through the nozzles and blows out the arc ; it also fills the inner cylinder 2 through the non-return valve 21. When the pressure is cut off, the valve 21 closes, a latch 24, 25 held in place by the gas pressure is withdrawn by a spring and the gas trapped above the piston 23 separates the isolating contacts. The break contacts are now reclosed slowly, the air escaping slowly through throttling conduits from the cylinders containing the pistons 13 .. 16. To complete the circuit low. pressure is admitted to the underside of the piston 23 through the valve 22 the pressure being too low to cause closure of this valve or of the valve 21.