Patent GB-366130-A (GB)
Title: Improvements in or relating to door operating devices for elevators
IPC: B66B13/06
Filed: 1930-10-31
Abstract: 366,130. Operating lift doors. THORNTON, A. A., 7, Essex Street, Strand, London. -(Peelle Co.; Stewart Avenue, Brooklyn, New York, U.S.A.) Oct. 31, 1930, No. 32767. [Class 78 (iii).] An electrical operator for lift doors of the kind having sections vertically and oppositely movable in guides in the shaft comprises link chains connecting the door sections and passing over sheaves driven through gearing by electric motors, one on each side of each door, a main power line, branch lines to the motors, a normally open switch in each branch line operable only when a car is in position, polechanging switches and electromagnetic control mechanisms therefor and a selectively operative remote control. Eachupper door section 12 is connected to a hanger bar 14 on the lower door section 12a by link chains 17 passing over sheaves 18 driven through gearing by motors 22, 23, the motors and gearing being positioned in the elevator shaft to avoid piercing the wall and one motor being provided on each side of each door. For use with a multiphase system, as shown, power lines 30, Fig. 3, extend throughout the shaft from which branch lines 33 extend adjacent each door to the motors 22, 23. Controlling the circuits to the shaft power lines are two groups of pole-changing or door opening and closing switches 36, 48 for reversing the rotation of the motors and thus opening or closing the doors. The switches 36, 48 are connected to the shaft power lines through leads 39, 51 and to the main power lines 45 through leads 42. A normally open shaft switch 54 adapted to be closed by a shoe 56 on the car prevents operation of the motors except those at the landing where the car is in position. The actuating means for the door opening and closing switches comprises two electromagnets 57 energized through remote control switches in the car, at the floors, in the benthouse or elsewhere, the remote controls being selectively actuated as desired. The car switch 61 includes normally open opening and closing switches 62, 63 and a normally closed holding or stop switch 64. A time limit switch 73 has normally closed contact members 74, a solenoid 72, a compression spring 81 and a dashpot 82. The opening and closing switches may also be controlled by a car-levelling control switch 86 having an electromagnet 89 in circuit with a car-levelling motor 90. The floor switches 61a are similar to the car switches 61 but are in circuit with a normally open car position switch 96 having a movable contact 97 operable by the car. To guard against " stealing the car " a stealing switch 98 is used and is open when the car is in motion and vice versa, its electromagnet 99 being in circuit with the motor 100 for imparting movement to the car. The operation is as follows : When a car stops at a landing' the shaft switch 54 is' closed, the attendant closes the opening switch 62 of the car switch 61 and so causes energization of the electromagnet 57 and closing of the door opening switches 36, so that the motors 22, 23 are energized and the door opens, the time limit switch 73 keeping the circuits closed for a set time. If the time interval is insufficient a second actuation of the car switch is necessary. To close the door the constant pressure closing switch 63 is actuated and the door closing switches 48 are thus actuated to cause the motors to rotate reversely. The link chain 7 can slip over the sheaves in the event of overrunning. To interrupt the opening movement of a door the stop switch 64 is opened. When used in an automatic lift a switch 61a is positioned on each floor and actuated by the car. When car-levelling mechanism is used, energization of the motor 90 causes energization of the electromagnet 89 of the switch 86 which is in circuit with the electromagnet 57. and thus actuates the door opening switches 36.