GB582701A - Improvements in or relating to gas-operated electric switchgear - Google Patents

Abstract

582,701. Gas-actuated switches. REYROLLE & CO., Ltd., A., ALLAN, A., and SHANNON, R. Nov. 14, 1944, No. 22462. [Class 38 (v)] [Also in Groups XXVIII and XXIX] In a switchgear unit A including a gas reservoir B for operating the switch-gear, the gas supply line to the reservoir is protected against leakage arising within the unit by a lock-nut valve F which closes at reduced pressure and remains closed, even though the original pressure is restored, until deliberately reopened. The valve G', Fig.2, is biassed by a spring G<8> to close the gas supply passage F<1>, but is normally retained open in its seating H<2> communicating with the atmosphere at G'. When the pressure falls below a predetermined value, the spring G' overcomes the gas pressure and the valve snaps. on to its seating H', the section area a<2> being less than a. The section area a' is also less than a, so that return of the normal pressure to the passage F' does not reopen the valve. The valve carries contacts M which complete an indicator circuit N when the valve closes. Where a number of unit reservoirs are supplied from a main reservoir C through a buspipe D and branch-pipes D', a lock-nut valve F may be arranged in each branch-pipe and/or net to the reservoir C at P, an isolating valve D' and a non-return valve B' being included in each branch-pipe The gas used may be air, hydrogen, argon, nitrogen, or dichlorodifluoromethane.