GB1272521A - Elevator control system - Google Patents

Abstract

1,272,521. Lift control systems. OTIS ELEVATOR CO. 2 Feb., 1970 [27 Feb., 1969], No. 4930/70. Heading B8L. In a multi-car elevator control system, the landings are segregated into a plurality of groups to divide the building into zones, each car having an assignment switch which is actuated when the car is located in a zone in which it is the only car present. A zone switch, individual to each zone, is actuated when an assignment switch for a car in that zone is actuated, whereby the response to landing calls registered in that zone is limited to cars located therein. When the assignment switch is unactuated, the car is moved until it is located in a zone in which it is the only car present, so that the cars are distributed into the various zones. An indicator, individual to each zone, is actuated in response to a predetermined level of traffic in the zone to actuate a zone demand switch and bring an outside car toward the zone regardless that the zone switch for that zone is actuated. The actuated zone demand switch prevents movement of a car, whose assignment switch is unactuated, toward any zone other than that associated with the said zone demand switch provided the car is not responding to a car or landing call. A switch in each car enables the car to by-pass calls registered at those landings it encounters in travelling to a zone in response to actuation of a demand switch. A traffic indicator associated with the zone including a main landing comprises load measuring apparatus individual to each car and operating in response to the car leaving the main landing in a given direction, either with a predetermined number of car calls registered therein or carrying a particular load, the main landing zone traffic indicator being actuated when a predetermined number of cars are travelling in that direction with their load measuring apparatus operated and less than a predetermined number of cars are present in the main landing zone. A traffic indicator, for a zone other than the main zone, is actuated when there is a predetermined number of registered landing calls in its respective zone and the absence of a predetermined number of cars, or if the said number of cars is present and there is a greater number of landing calls.