GB190420613A - Improvements in and connected with Lifts and Hoists. - Google Patents

Abstract

20,613. Waygood & Co., R., and Walker, H. C. Sept. 24. Lifts.-The armature of an electromagnet is connected to the lift door and is arranged so that, after a predetermined time has elapsed, the door is automatically shut. On each floor, near the liftenclosure door, is fixed a solenoid A, the armature of which is connected by levers, as shown, to a rack-bar r which turns a toothed quadrant fixed to the door. The coil of the solenoid is connected up to a double-contact switch B, which is operated by the movement of the door. Wires are led from the switch B to the main lead x and to the timerelay magnet C. This consists of a coil passing around a core c with an extension carrying two contacts e, f and working in a dash-pot m. Two fixed contacts h, i are connected respectively to the solenoid A and to the negative lead y. When the door is opened, the circuit 2 to the controller is broken by the movement of the switch B into the position shown in dotted lines. The current is diverted through the relay magnet C which, after a predetermined time, attracts the core c and causes current to pass through the solenoid A, thus closing the door. The invention is described with reference to an electric lift, but is equally applicable to lifts operated by hydraulic or other means.