GB989796A - Improvements in and relating to electrical switch actuating means - Google Patents

Abstract

989,796. Actuation of switches; controllers. ASSOCIATED ELECTRICAL INDUSTRIES Ltd. Oct. 8, 1963 [Oct. 29, 1962], No. 40823/62. Heading H2B. An actuating shaft 1 for the switches 16, 17 of an on-load tap changer is rotated by an electric motor 5, and the arrangement includes a flywheel 8 on the motor shaft, a brake 6 and a brake timing cam 7 on a shaft 3 driven by the motor and flywheel, which cam controls the brake to stop the motor 5 and actuating shaft 1 if the power supply to the motor is interrupted before sufficient time has elapsed to ensure a flywheel charge which will complete a tapchanging operation. A pivoted arm is movable electromagnetically to make a switch in the motor circuit, the arm bearing a roller cooperating with segments on the timing cam 7 such that when the arm falls through a gap between the segments, the motor supply is interrupted and the brake engages (Fig. 2, not shown). In normal operation the flywheel 8 charges up sufficiently to rotate shafts 9, 12, for one tap-changing operation after a limit switch for motor 5 is actuated by a member rotating with timing cam 7 to break the motor circuit. Ratchet wheels 14, 15 are arranged for turning in one or the opposite direction through coupling 13, the shaft 12 of a selector switch 17, Figs. 1, 3. Manual operation is provided by a handle (not shown) on the motor shaft 47 which rotates shaft 3 and moves a coupling 2 through a member 50 such that projections 55 on a disc 56 engage a forked plunger 57 and the energy stored in a spring 65 gives a quick action to the tap-changing operation (Fig. 4, not shown).