GB375782A - Improvements in and relating to telegraphic installations - Google Patents

Abstract

375,782. Telegraph exchange systems. LORENZ AKT.-GES., C., 1, Lorenzweg, Tempelhof, Berlin. March 27, 1931, No. 9415. Convention date, March 29, 1930. [Class 40 (iii).] Each subscriber station of a telegraph exchange system is provided with apparatus which, under the control of an initiating signal from a distant subscriber, sends a return signal, and which incorporates means for preventing the emission of the return signal if the receiving apparatus is out of order for reception. Additionally the apparatus is arranged to prevent the transmission of a return signal by the apparatus of a subscriber who has initiated the transmission of a reporting signal from the remote station with which he is connected. To initiate the reporting signal, a subscriber operates a key-lever effecting the transmission of a code combination of impulses which, at each station, operates a bar Z closing over operated contact z and released contact v, at the distant station, the energizing circuit of a magnet winding M. The core g<2> operates a ratchet wheel mechanism f, i to rotate for one revolution a shaft K carrying a cam wheel K<1> which, at contact K<4> effects the transmission of the impulses for return signal. The rate of transmission of the impulses is regulated bv a synchronizing arrangement S, S\ controlled by brushes c, c<1> associated with a commutator C on the shaft of the telegraph motor. When a subscriber operates his key T to initiate the return signal from a distant station, the slowrelease relay V energizes, and at contact v opens the circuit of the relay M to prevent the operation of the reporting apparatus at the initiating station. If the receiving tape P is torn or used up, a roller R falls into a slot L in the guide-plate F, and closes contacts pl, p<2> over which the relay V is energized to prevent the relay M from being operated when the contact z is closed by the initiating signal from the distant or calling station.