GB567405A - Improvements relating to electrically-driven machines having built-in motor control gear - Google Patents

Abstract

567,405. Controllers ; switchboards. ADCOCK, G., and SHIPLEY, H. June 10, 1943, No. 9311. [Classes 38 (iii) and 38 (v)] Control gear for an electrically - driven machine having an individual motor is mounted in a drawer-like structure which pushes into the body of the machine, in the case of built-in control gear, or a cabinet separate from the machine, an isolating switch being provided for de-energizing the control gear before the drawer can be pulled out. Fig. 1 shows control gear, such as fluidfilled contactors 15, transformers 16, timing relay 17 and overload switches, mounted in a partitioned metal drawer 13 which slides on rollers 19 into a recess 10 in the body 11 of a machine. The runners 18 for the rollers preferably extend beyond the rear of the drawer to support the latter when fully withdrawn from the recess, complete withdrawal being prevented by a stop 21 attached to the rear of the drawer and travelling along a rod 22. Plug-in contacts may be associated with the drawer and a stationary part of the machine to de-energize the control gear and motor before the drawer can be opened, but, preferably, an isolating switch of the kind described in Specification 539,497 is provided in a recess 24 at the other side of the machine bed, the switch including contacts 25, 26 which, when its pivoted door 27 is opened, automatically disengage to de-energize the control gear. Opening of the door releases a pivoted catch 30 which normally engages a keeper 31 on the back of the drawer to prevent opening of the latter. In another construction the control gear is mounted in two drawers arranged one above the other and sliding on runners secured to a framework fixed in the recess in the machine.