JPS5613866A - Communication device - Google Patents

Abstract

PURPOSE:To ensure an automatic calling of the prescribed telephone in an emergency and even in case nobody is in the guarding room and then realize the talking with the telephone in an elevator, by holding a certain state for a fixed time with occurrence of the request signal and then carrying out the dial output. CONSTITUTION:When push-button 2 is pressed in elevator 1 and in an emergency, signal detecting part 3 starts to give the control to MF signal oscillating circuit 5 via FM signal control circuit 4. Then the abbreviated dial number of the pushphone is sent to central office lines L1'' and L2'' each. At the same time, part 3 gives the start to main wire starting circuit 9 to form a DC loop to central office lines L1' and L2'. Receiving this signal, the switchboard of the telephone office connects this signal to the number of the called subscriber which is stored previously. When the called subscriber gives the answer, the current of the telephone circuit is reversed. And then information tone control circuit 11 is started via answer detecting circuit 10, and the information tone is sent to the called subscriber from information tone signal generating part 13. At the same time, relay contacts l<1> and l<2> are closed in a delay of a fixed time and after the relay of circuit 10 worked, and thus the talking circuit is closed. As a result, the talking becomes possible between telephone transmitter 16 and the called subscriber.