Patent GB-365157-A (GB)
Title: Improvements in signal and/or control systems for elevators, hoists and the like
IPC: B66B1/18
Filed: 1930-10-13
Abstract: 365,157. Lifts. ASSOCIATED ELECTRICAL INDUSTRIES, Ltd., Crown House, Aldwych, London.-(Assignees of Eames, W. F.; 207, Ross Avenue, Wilkinsburg, Pennsylvania, U.S.A.) Oct. 13, 1930, No. 30637. Convention date, Oct. 11, 1929. [Class 78 (ii).] Electric plant.-In a control system for a number of cages operating in adjacent shafts past the same floor, having electric switching means common to the cages and adapted to control electric circuits individual to the cages to register calls for service at the floor, and having means individual to each cage for receiving such calls, or which can be actuated in response thereto for effecting predetermined cage speed change, there is provided for each cage an electrically actuated relay which operates when a predetermined voltage is applied to its operating element, these operating elements being included in different branches of a circuit, the common portion of which includes the call registering switching means and current modifying means, e.g. a resistance, and which circuit after being prepared by actuating the call registering electric switching means is completed through one of its branches by contacts actuated in response to the approach of a cage within a predetermined distance of a floor, whereupon that relay, the operating element of which is included in the completed circuit is operated and thereby renders the call receiving or speed change means responsive to a registered call for service while the current modifying means is rendered effective to enable the voltage available to the remainder of said branches below the predetermined value required to operate the relays for the cages corresponding to the remaining branches. Specification 355,513 is referred to. There is provided for each cage a pair of blocking relays C1A, C2A which are selectively operable according to the distance in advance of the floor of the cage at the time the signal is made, resistances 115, 102 associated with these relays, and resistances 2RU, 2RD, &c. associated with the pushbuttons 2FU, 2FD, &c. at the various floors. If the cage is called, e.g. to the third floor by the actuation of pushbutton 3FU, when it is still at a distance of almost two floors from the third floor, the brush 22a on the movable arm MA of the floor selector FSA connects the segments 90, 96 of group 22 to complete a circuit for the coil of relay C2A. In closing, the relay C2A places the resistance 102 in shunt relation to the coil 100, and thereby decreases the resistance of the call registering circuit which includes the resistance 3RU. The voltage drop across the resistance 3RU, therefore, is increased. If then a second cage should approach the third floor, a similar circuit would be completed by its floor selector, but the voltage available to its blocking relay would be below the value necessary to actuate it. Therefore while the relay C2A, or the relay C1A if the call is received later, is energized, the corresponding relays of the other cages are ineffective to complete the call receiving circuits for those cages.