Patent GB-486598-A (GB)
Title: Improvements in or relating to elevator signal and control systems
IPC: B66B1/34
Filed: 1936-12-07
Abstract: 486,598. Electric control systems for lifts. WESTINGHOUSE ELECTRIC & MANUFACTURING CO. Dec. 7, 1936, No. 33601. Convention date, Dec. 7, 1935. [Class 40 (i)] [Also in Group XL] In a lift system, call signals are registered automatically by the passage of intending passengers through beams of light co-operating with photo-electric cells. The calls are registered on bands of relays individual to each car and the arrangement is such that calls exceeding a predetermined maximum are registered for the next following car. Zoning arrangements under the control of the cars are provided in order to govern the distribution of calls between the cars. Figs. 1 and 2 show the photo-electric equipment installed in the lift corridor of a floor and Figs 6, 7, 8 the control circuits for a pair of lifts A, B. Calls initiated by passengers passing through the " up " and " down " car entrances 50, 51 are registered in up and down relay groups UR, DR, Fig. 7, and the appropriate lift is driven by a Ward-Leonard motor control system under the control of the register relays and a floor selector. The passengers are counted by stepping magnets DH, UH controlled by the photo-electric corridor equipment and adapted to render the register relays inoperative by calls exceeding a predetermined number. Zoning relays UZ, DZ, Fig. 8, common to all the lifts are operated by the floor selector switches in order to define the signal zones of the lifts. The lower half of Fig. 8 shows the light sensitive equipment associated with the " down " and " up " entrances at one floor. As shown, the system is arranged for automatically slowing and stopping a car at a calling floor by the provision of inductor relays operated by inductor plates located on the lift shaft. Registration of calls. Each entrance to the lift corridor is provided with a pair of photoelectric cells UT, UQ ; DT. DQ illuminated by beams of light 62 ... 65 from a source 60. Passage through an entrance in the correct direction interrupts the beams successively to operate preparing and operating relays, e.g. 3UW, 3UX, in the correct sequence and thereby pull up the corresponding call registering relay, e.g. 3UR in the groups of up and down relays 1UR.. 4UR, 2DR.. 5DR, Fig. 7. Passage through an entrance of passengers leaving the lifts causes operation of the light cells in the reverse order to prevent energization of the appropriate operating relay and the registration of a call. Operation of lift. When a register relay, e.g. 3UR is pulled up, a stopping contact 3a, Fig. 6, on the floor selector is marked, a floor lantern 3UL is lit to indicate to the passenger the lift answering the call and a relay 3UP, Fig. 8, is operated to prevent registration of the call in other cars which may enter the zone of the car accepting the call. The car is started by movement of the attendant's switch CS in one or other direction to operate a door closing relay 45 and one or other of direction switches U, D and a relay M for preparing the circuits of the inductor relays. The operated direction switch starts up the winding motor 10 and pulls up relay V which cuts out resistance 19 to speed up the motor. When the lift approaches the calling floor, relay S is operated over the marked contact 3a to render effective the slowing and stopping inductor relays E, F, and bring about the slowing and stopping of the lift. When the car stops the attendant centres the car switch to release relay 45 and permit opening of the car door. Zoning arrangements. As previously described a common bank of zoning relays 1UZ ... 4UZ, 2DZ ... 5DZ is controlled by the floor selectors of the lifts. These relavs control contacts in zoning circuits 67, B67, Fig. 7, associated with the register relays of the lifts and the arrangement is such that depending on the positions of the lifts selected, contacts in all the zoning circuits are opened to define active zones wherein each car receives stop calls without affecting another car. Quota system. Mechanism is provided for counting the number of persons passing through an entrance at one floor or the entrances at several floors, in order that calls exceeding a predetermined number may be excluded from a car and registered in the next nearest approaching car. Each counting mechanism comprises a cam-operated switch operated step-by-step by a ratchet magnet UH or DH, Fig. 6. Each magnet is controlled by contacts of the registering relays and preparing and operating relays controlled by the photoelectric apparatus. The registration of a call by a passenger, and interruptions of the light beams by further passengers operate the counting magnet step-by-step until when the quota is reached, the cam-switch opens contacts, e.g. UH1, Fig. 7, which prevents the registration of further calls for the car during its trip to a terminal floor. The switch also disconnects the zone relays of the car from the supply circuit thus excluding the car from the zone circuits. Further calls are registered on the relays associated with the next nearest car travelling in the direction of the calls. The counting mechanism is reset by limit switches UL, DL when a car reaches the terminal floor. Alternative system. The cars may be operated in accordance with lamp signals instead of automatically as previously described. When operated in this manner, switches 104 are actuated to switch the lamps 103 into circuit with the contacts of the stopping relay S so that when the latter relay is operated on approaching a calling floor a lamp signal is given to the car attendant.