GB172125A - Elevator control system - Google Patents

Abstract

172,125. Marks, E. C. R., (Randall Control & Hydrometric Corporation). Sept. 2, 1920. Lift cages and doors, locking and unlocking and operating.-A switch in the circuit of the actuating motor is connected to the locking device of each well door so that the switch is opened when any door is unlocked and is held open until all the doors are looked. Each well door 3 has a notched bolt 4 which, when the door is closed, is engaged by a projection 27 on the arm 9 of a three-armed lever 7, 8, 9 mounted in a look casing 5. The arm 8 projects from the casing and carries a transverse pin 12. The arm 7 also projects from the casing and has a slot through which passes a vertically movable wire 13 suspended by a spring 14 and tensioned by a weight 15. A stop 16 is fixed to the wire above each arm 7 so that when any arm moves upwards, the wire is raised and the switch 20 in the circuit 17 of the motor 18 opened. At the same time the door is unlocked. The arm 7 is locked in the raised position by the engagement of latches 32, 30 with pins 34, 36 on the arms 9, 8. These latches are disengaged when the bolt 4 is inserted in the casing. The arm 7 is raised by depressing a pedal 31 on the lift, thereby bringing a shoe 28 on the lift into contact with the pin 12. When the motor 18 is running, a solenoid 49 is energized and its core 48 is raised, thereby moving a serrated bar 46 into locking engagement with a similar bar 45 attached to the wire 13. Upward movement of the wire is thus prevented, and consequently no door can be unlocked. When an hydraulic motor is used for actuating the lift, the switch 20 is arranged in a local circuit with a relay 38, Fig. 5, which actuates a switch 39 controlling a circuit containing solenoids 42. Brakes 43 are applied to and released from a movable part 44 of the motor by the solenoids.