Patent GB-1251243-A (GB)
IPC: H01H3/22
Filed: 1969-01-16
Abstract: 1,251,243. High-voltage switches; actuation of switches. S & C ELECTRIC CO. 16 Jan., 1969 [16 May, 1968], No. 2690/69. Heading H1N. A drive shaft 29, Fig. 1, for rotation in opposite directions to effect opening and closing of a high voltage switch 10, which may be that of Specification 972,037, has an extension 43 driven by an electric motor 64 via a clutch 45 engageable only when the shaft extension 43 and motor driven shaft 48 are in one predetermined relative angular position, an auxiliary shaft 191 having a driving connection with the shaft 43 and thus indicating the angular position of the drive shaft 29 and switch 10, and a control shaft 203, Fig. 5, having a driving connection with the shaft 48 and thus indicating the angular position of the motor 64. To inspect and check the opertaion of the motor driven mechanism, without operating the switch 10, the motor drive cultch 45 is declutched using a handle 38. Then reclutching is possible only when the drive shaft 29 and motor 64 are in the same angular relation as shown by indicators 192, 197, on shafts 191, 203. A handle 36, foldable in non-operated position, Fig. 1, and non-detachably connected to the speed-reducing train between the motor 64 and shaft 43, permits manual operation of switch 10, a band crank interlocking switch 135 being opened when the handle 36 is unfolded to prevent energization of the motor 64. A limit switch assembly 216, having several pairs of contacts, is operated by the control shaft 203 to control the de-energization of the motor 64 at the ends of the opening and closing strokes of switch 10, the shaft 203 having a " close " cam 207 and an " open " cam 208 engaging rollers 209, 210, on a cam follower 211 secured to a shaft 211<SP>1</SP> which operates switch assembly 216, an auxiliary signalling and control switch 219, and a motor position indicator 220. Motor 64 is stopped by a spring operated brake 69 which is released when the motor is energized, when handle 36 is unfolded, and when the handle 38 unclutches the clutch 45. A manual clutch 92, 95, is provided between the handle 36 and the manual drive shaft 56, and a brake release rod 147 is operated as the clutch is engaged. Handle 36 is padlocked to prevent unauthorized unfolding, and a spring- biased knob 129 must be pulled to permit unfolding. A spring-biased knob 185 holds handle 38 in either of its two positions. A control switch 229 is provided for manually initiating energization of motor 64 to operate switch 10, green and red indicating lamps 230, 231, showing when the switch 10 is open and closed. The control system, Fig. 17, (not shown) includes a stepping relay coil 242 for controlling the energization of parallel connected auxiliary trip windings 245, 246, 247, arranged to effect the tripping of the interrupter operating mechanism 18 of the individual poles 11, 12, 13, of switch 10 for effecting operation of the respective load current interrupter 19 in advance of the normal operation thereof, upon overcurrent flow in the transmission system to which switch 10 is connected. A push button switch 243 is provided for manual energization of coil 242, Fig. 17, (not shown). If coil 242 fails, a timer 248 ensures energization of motor 64 to open switch 10. Handle 38 operates a decoupling switch 182, Fig. 15 (not shown), to prevent the auxiliary trip windings 245, 246, 247, from being energized when clutch 45 is unclutched.