GB257010A - Improvements in or relating to electrical switchgear - Google Patents

Abstract

257,010. Reyrolle & Co., Ltd., A., and Coates, F. May 19, 1925. Sliding switch-carriage arrangements; electromagnetic switches; switches, quick-action. - Sliding carriage switchgear arrangements for automatic substations are provided with a number of auxiliary switches mounted on the fixed switchgear portion with their actuating mechanisms and arranged so that when the draw-out portion is in its closed position the operation of the main switch contacts actuates also the auxiliary switches. In the form shown in Fig. 1 in which the auxiliary switches are mounted on the fixed structure and are operated mechanically through a link F attached at one end to a crank F<1> on the switch spindle and at the other to a downwardly-pressed spring plunger E carrying a roller at its lower end. The draw-out portion A is fitted with a sliding rod D connected at one end through a bell-crank C<1>, C<2> to the actuating mechanism A<4> of the main switch A<1>. The other end of the rod D has an inclined face D<2> which is brought near to the roller on the arm E when the member A<1> is moved into position so that on subsequent closure of the main switch the plunger E is raised and the auxiliary switches operated through the link F. When the auxiliary switches are operated electromagnetically as shown in Figs. 3 and 4 they are mounted on a shaft M together with switches G<2>, G<3> controlling the circuits of solenoids H, H<1> which are provided for rocking the shaft in opposite directions. The cores of the electromagnets H, H<1> are secured to arms K, K<1> of a pivoted lever which has a third arm L with a pin-andslot connection to a lever L<3> loosely mounted on an extension of the shaft M. This extension also carries a lever N pivotally secured at one end to a dead-centre spring O, lost motion connections N<1>, N<2> being provided between levers L<3> and N and lever N and the shaft M. When the main switch J, Fig. 5, is closed, it moves over a change-over switch J<1> and completes the circuit of electromagnet H through switch G<2>. The electromagnet H then moves over the shaft M with a snap-action, breaking its circuit at switch G<2> and preparing a circuit for the electromagnet H<1> through switch G<3> which is closed on the opening of the main switch. The auxiliary switches are mounted in a base G secured to the fixed switchgear portion, the switch J<1> being carried on the draw-out portion and connected to its controlled circuits by an additional threepin plug coupling. The contacts of the auxiliary switches may be arranged as required and some of these switches may be arranged to operate with a suitable time-delay action.