Patent GB-538967-A (GB)
Title: Improvements in control device for lifts
IPC: B66B1/16
Filed: 1940-03-05
Abstract: 538,967. Push-button lift systems. INVENTIO AKT.-GES. March 5, 1940, No. 4128. Convention date, April 1, 1939. [Class 40 (i)] In a collector-type system of the kind in which the car can reverse its direction at the farthest landing to which it has been summoned, the direction in which it will travel after stopping is pre-determined and is shown on an indicator. In one arrangement, when such a reversal is required, the car travels to the next floor and then reverses before stopping at the remotest calling floor. In a modification, it stops at the calling floor, the reversal of the indicator taking place as it does so. Circuit arrangements.-The drawings do not follow the usual convention as regards the reference characters given to relay contacts but the manner in which any contact in Fig. 3 is actuated can be ascertained from Figs. 1 and 2. For convenience, the ground floor is referred to as the first floor, the first floor as the second, and so on. Assuming the car to be at the first floor and " up " and " down " buttons 302, 301 to be operated at the third, call-registering relays 321, 311 pull up and lock energizing " up " relay 41 which lights the " up " indicator lamp and energizes auxiliary relays 431, 231 selected by the register relays and the " up " coil 6 of the contactor controlling the drive. The latter energizes a relay 15 for holding the auxiliary relays. Just short of the second and third floors, contacts 208, 308 are opened momentarily and, since 321 is operated, the lift is thus stopped at the third floor by the release of the contactor. Re-operation of the contactor when 308 closes again is prevented by dash-pot relay 13, which was operated with the contactor and left the latter dependent on one of its own contacts, for a period long enough for the intending passengers to open the gate and so open a further point in the contactor circuit. When the gate is re-closed the car rises again, opens contact 310 to unlock the relay 321 on which the " up " call was registered and changes over contact 306. Since the next is the top floor, the " up " relay 41 is released by the liftoperated contact 406, the lift stops and " down " relay 31 is operated and lights the " down " lamp 37, but without immediate effect on the contactor owing to the action of the dash-pot relay. When the passenger closes the gate on alighting, however, the down coil 5 is operated and the car descends, being stopped at the third floor by the momentary opening of contact 307, the shunt round which has been removed by relay 311. When the new passenger closes the gate, the car descends and the register relay is unlocked bv contact 309. In the absence of floor calls, the next stopping place is determined by the car buttons 103, 403. Assuming the first floor to be wanted, register relay 111 operates and the car is stopped by the relapse of 31 when contact 106 is opened. Relays 231, 431 are released when 31 falls and register relay 111 is released at 105. If, now, " down " calls are made at the second and third floors, register relays 211, 311 operate and then " up " relay 41 " up " coil 6 of the contactor and auxiliary relays 131 ... 431. The " up " indicator glows and the car rises. In the absence of " up " calls the car, with the circuits shown, travels to the top floor, reverses, picks up the passenger on the third floor, descends to the second, picks up the passenger there and then descends again. In a modification in which contacts 215, 315, 225, 325 are omitted so that in the circumstances just described only 131, 231 of the auxiliary relays are energized, the car terminates its upward journey at the third floor owing to the release of 41 by the change-over of contact 306. Relay 31 for the other direction pulls up immediately and the " down " indicator glows. When the passenger closes the gate the car descends as before.