Lift control and security system for multi-storey building - requires passenger to enter secret code for certain floors after altering decoding circuit via prescribed key

摘要

The floor selection keyboard (12) in the lift is wired to the control system (10) via a microprocessor-controlled coding circuit (16) bypassed by the wires from keys (1-3,6) corresp. to those floors which are accessible to all comers. For access to other floors (4, 5, 7) the visitor must press the ground-floor key (0) briefly to activate the circuit (16) before keying-in the code known to him or her. A correct code is acknowledged by a lamp (18). USE/ADVANTAGE - In building where access to some floors is restricted to authorised persons. Easily installed and operated system affords higher security.