| 摘要 |
723,156. Gas-blast switches. BRITISH THOMSON-HOUSTON CO., Ltd. June 23, 1952 [June 26, 1951], No. 15759/52. Class 38 (5). An operating mechanism for a gas-blast circuitbreaker having an isolating contact 6 and an interrupting contact 4 comprises a blast valve 14 to control the supply of gas to the interrupting contact, the valve 14 being operated by a piston 19 having a projecting undercut portion 44 which acts as a sleeve valve to admit gas to a fluid motor 23 controlling the operation of the isolating contact. In the multi-pole arrangement shown, when a main valve 21 is opened, gas pressure is applied through conduits 20 to pistons 19 which move upwardly opening the blast valves 14. Gas now flows through conduits indicated at 18 to the circuit-breaker units 1 ... 3, the blast opening finger contacts 4 against the bias of springs 5 and extinguishing the arcs drawn. During the upward movement of the pistons 19, the undercut portions 44 of the piston rods 15 establish communication between ports 46, 47. Compressed gas now flows through conduits 48, 49, 50 and 43 to the fluid motor 23. The resulting downward movement of the piston 42 " breaks " an overset toggle 35, 36 so that a spring 33 aided by the piston 42 and gravity moves a connecting rod 32 to the right. The rod 32, through " straight-line " linkages 25, 27, 29, moves the isolating contacts 6 downwardly to complete the opening and isolation of the controlled circuit. When the master valve 21 is closed, springs 16 close the blast valves 14 and the contacts 4 return to their initial positions. The isolating contacts 6 are restored by opening a valve 54 so as to supply gas through a conduit indicated at 55 to the underside of piston 42. If the circuit-breaker is to operate as a reclosing circuit-breaker, a valve 51 is closed to prevent the supply of gas to the fluid motor 23 so that only the contacts 4 may be operated under the control of the valve 21. Specifications 549,756, 583,346 and 712,436 are referred to. |
