Patent GB-191424701-A (GB)
Title: Automatic Phonographic Responding and Receiving Devices for use with Telephones.
Inventor: SEELAU FRANZ
IPC: B41J11/36
Filed: 1914-12-28
Granted: 1915-12-28
Abstract: 24,701. Seelau, F., and Newman, A. M. Dec. 30,1913, [Convention date]. Telephone communications, recording and reproducing.-Relates to phonograph apparatus for responding to telephone calls and recording the callers' messages, and comprises means for automatically starting the responding - phonograph, altering the connexions to put the recording- phonograph in circuit, restoring all the parts to initial position when the message is completed, and actuating the supervisory signals at the exchange at the beginning and end of the conversation. The calling-current rings a bell 4, Fig. 1, and energizes the winding 7 of a relay 6, the armature 9 of which opens the circuit of winding 7 at the contact 35 and closes two local circuits, one including a winding 8 for holding up the armature 9, and the other including a motor 11. This motor first operates the switch 3 and gives the supervisory signal at the exchange, and then closes switches 36, 37 arranged respectively in the primary and secondary circuits of a transformer 38. A responding-phonograph record in contact with the stylus of the microphone 28 is then rotated, and the message recorded thereon is transmitted to the calling subscriber. When this is completed, a switch 29 is closed to energize an electro-magnet 30, which (1) disconnects the responding-cylinder from its driving- gear and couples the recording-cylinder, (2) opens the primary and secondary circuits of the transformer at the contacts 31, 32, (3) closes a switch 33 for connecting the receiver 27 to line, and (4) closes a switch 34 in a local battery circuit containing a magnet 19 and a microphone 26. This microphone is coupled mechanically to a receiver 25 in parallel with the recording-receiver 27. During the receipt of the caller's message, the resistance of the microphone 26 is reduced by the talking-currents, so that the magnet 19 is energized and its armature 18 attracted. A detent 17 is thus withdrawn from behind the lever 16, which is swung to the right by the action of a spring 13 previously compressed by the arm 12 of the armature 9. At the conclusion of the caller's message, the increased resistance of the microphone 26 reduces the current through coil 19 and allows the armature 18 to resume its position, thereby closing contacts 21 and energizing a resetting-magnet 22, which restores the armature 9 and lever 16 to their initial positions and opens the circuit of the motor 11. A dash-pot 23 prevents premature resetting when a short break occurs in the message. The contacts 21 may be arranged in the circuit of the locking-coil 8 and are then opened by the rising of the armature 18. If no message is transmitted by the caller, the parts are reset by momentarily energizing the magnet 19 by closing a contact 44 after the recording-cylinder has made a few revolutions. In a modification, Fig. 2, the lever 16 and related parts are dispensed with, and the armature 9 of the calling-relay 6 is arranged to start the motor 11 by closing a switch 10<a>, and to close the circuit of the locking-coil 8 at the switch 10. At the beginning of the caller's message, the magnet 19 is energized as before and closes a switch 21<a> in circuit with the locking-coil 8, and also a switch 42 arranged to energize a magnet 40. This magnet closes a hold-up contact 41 and opens a switch 39 in parallel with the switch 21<a>. When the caller's message is completed, the magnet 19 releases the switch 21<a>, which opens under the control of a retarding-device, as in the first-described apparatus, and the calling-relay 6 is de-energized, thereby stopping the motor 11 and opening the circuit of the magnet 40 at the contact 43.