GB357654A - Improvements in and relating to fluid-break electric circuit interrupters - Google Patents

Abstract

357,654. Oil-break switches. BRITISH THOMSON-HOUSTON CO., Ltd., Crown House, Aldwych, London.-(Assignees of Hilliard, J. D. ; Hotel Hough, Schenectady, New York, U.S.A.) July 1,1930, No. 19965. Convention date, July 1, 1929. [Class 38 (v).] Fluid-break switches have means for maintaining the oil or other liquid level substantially constant, so that enough air is available in the tank for cushioning and enough liquid to provide proper insulation. A main tank 1 containing the switch communicates through a port 22 with a chamber 21 from which a conduit 25 leads to a reservoir 27. A valve 26 in a chamber 32 communicating with an impeller 30 is controlled by a float 23 so as to allow surplus oil to flow from the tank 1 into the reservoir 27 and to prevent excess oil being transferred by the impeller in the reverse direction. The impeller is driven by a motor 29 under control of an oil-level switch in a chamber 38 which communicates with the main tank. Low oil level causes a float 40 to bridge contacts 43, 44, whereby the motor is caused to replenish the oil supply in the tank 1. If the valve 26 closes owing to the motor failing to stop, an indicator may be actuated or the motor circuit broken from the chamber 32. A vent 28 prevents sudden expulsion of oil from the tank 1. In a simpler form, Fig. 1 (not shown), an overflow pipe leads from the tank to the reservoir and the motor is continuously driven.