GB1208853A - High voltage switch having auxiliary latch operating means for the current interrupter - Google Patents

Abstract

1,208,853. Automatic circuit-breakers; loadbreak disconnecting switches. S. & C. ELECTRIC CO. 7 Feb., 1969 [3 April, 1968], No. 6706/69. Heading H1N. In a load-break disconnecting switch as described in Specification 972,037, in which an overcurrent solenoid-operated auxiliary trip 59, Fig. 1, is provided to trip a latch member 24, Fig. 2 (in housing 16), to release spring-loaded contacts (not shown) in a circuit interrupter 17 a collapsible linkage 92, 96 is provided (as in housing 35) whereby the latch member 24 may return to its latched position independently of the return of the solenoid trip 59. The contacts (not shown) of the circuit interrupter 17 are arranged in series with the main switch blade contact 18 which is opened subsequently by an operating link 14 acting through a rotatable insulator 12, coupled shaft 15 and linkage 19- 22. Rotation of shaft 15 also effects release of the latch mechanism 24 if not previously released by the auxiliary trip 59. The armature 84, Fig. 8, of solenoid 85 of the auxiliary trip 59 rotates a shaft 57 coupled through rotatable troque-transmitting shafts 37, 55 and insulator 38 to a shaft 34 in housing 35. Movement of the shaft 34 is transmitted to a shaft 29 carrying lever 27 engaging the latch release member 24, through levers 33, 31 interconnected by the collapsible links 92, 96. Spring 98 normally holds link 92 against a stop 94 on lever 31 whereby the links are held just over-centre for the transmission of thrust. After operation to the latched position (shown hatched) stop 94 moves links 92, 96 to the right of over-centre whereby a return spring 101 restores levers 31, 27 to their initial (full line) position by collapsing the links 92, 96. Stop 25 on lever 27 which initially engaged the latch release member 24, is thereby withdrawn from the member 24 to permit the latch to be reset irrespective of the return of the armature 84 and lever 33 to their initial positions. The coupling between the armature 84, Fig. 8, and shaft 57 includes a pivoted latch 74 which prevents inadvertent rotation of the shaft 57 unless the solenoid 85 is energized. The armature 84 is coupled to the shaft 57 through a freely-rotating lever 87 having a lost-motion connection 88, 89 with a lever 71 keyed at 70 to the shaft 57. The pivoted latch 74 normally engages a notch 72 on the lever 71 to prevent its movement and is released only by the initial movement of pin 81 on the armature 84 when the lost motion is taken up at the connection 88, 89.