Patent GB-453723-A (GB)
Title: Improvements in or relating to lift controlling systems
IPC: B66B1/16
Filed: 1935-07-12
Abstract: 453,723. Electric lifts. GENERAL ELECTRIC CO., Ltd., Magnet House, Kingsway, London, and SMART, N. C., c/o General Electric Co., Ltd., Stoke, Coventry. July 12, 1936, No. 19919. [Class 78 (ii)] [See also Group XXXVIII] Apparatus for lift control comprises a unit which may be jacked into position and operate in any one of a number of systems of control. As described the unit controls an automatic system, a collecting system and a system which can be switched from automatic to operator control. The control unit is shown in Fig. 1 and when this is jacked into apparatus wired as shown in Fig. 3 an automatic system is provided. When the lift is stationary, all gates are shut and gate contacts LA-LD are closed so that relay G is energized. If now a call is initiated from the 4th floor, button LP4 is depressed so that relay D operates and locks. Relays R and DR pull up and the " up-drive " contactor UD is energized to close the circuit for motor RO to drive the lift upwards. As the mid-point between each two floors is passed, the inductor relay Z is operated by a plate in the shaft and, as DR is energized, the magnet WU of switch W operates to drive the wipers anti-clockwise on to the next contact. As the lift approaches the fourth floor wiper W1 is stepped to the contact connected through d4 operated to relay PS so that when the stopping plate on the shaft energizes inductor relay S, relay R is shorted down, contactor UD releases to stop the lift and relay D falls away. Relay PS is de-energized but it holds up long enough to allow the lift gates to be opened. As the passenger enters the lift the floor switch FS is energized so that as soon as the gate is closed and relay G re-operated the relay H energizes to prevent landing pushes LP1-4 registering a call. Assuming the passenger now pushes button CP1, relay A is energized and locks; relay DR falls away as its top and bottom windings are energized in opposition, the down drive contactor DD is operated and the lift is driven downwards. The operation is then similar to that described above except magnet WD steps wipers W clockwise as the relay Z is energized. Wiper W3a is used to energize floor lamps when provided which are connected as shown in Fig. 4. Wiper W3b ensures that the switch and lift are in step. When the lift is in its top and bottom positions switches UL and DL are operated respectively. If wiper W3b should still be on the commoned contacts, relay T is energized over one or other of its windings and the switch is stepped by self-interruption until wiper W3b is off the commoning. The direction of movement of the switch is determined by the condition of relay DR. If the lift is to work on the collector system the wiring shown in Fig. 4 is provided. In these circumstances the lamps " UP " and " DN " indicate the direction of travel of the lift and lamps AL-DL the position. The landing and lift keys LP1-1, CP1-4 are all connected directly to negative so that the lift travels in one direction stopping at each calling floor until the last call is reached and then travels in the reverse direction. The operation is otherwise similar to that described above. If the unit is connected to wiring as shown in Fig. 5, the lift can be automatic or operator controlled depending on the position of contacts CO1-6. If the contacts are to the left, as shown, the system works automatically as described above with reference to Fig. 3. If the contacts are thrown to the right the operation is similar to the collector system shown in Fig. 4 except the registering relays A-D are controlled only by the lift pushes CP1-4, the landing pushes LP1-4 controlling hand-returned indicators F1-4 in the lift. The apparatus may be adjusted to accommodate more floors by the provision of additional relays as A-D, the contact chain a3-d4 being suitably extended. Specification 432,606, [Group XXXIX], is referred to.