Patent GB-328325-A (GB)
Title: Improvements in or relating to call recording apparatus for use in telephone systems
IPC: H04M1/57
Filed: 1929-01-26
Abstract: 328,325. Pollak, J. E., (Associated Telephone & Telegraph Co.). Jan. 26, 1929. Type-writing telegraphs. - Apparatus for obtaining a printed record, at a telephone substation from which the subscriber is absent, of the numbers of subscribers making calls thereto responds to a predetermined number of pulses of ringing current to bridge the line and give a signal to the calling subscriber, who then dials his own number. The recording apparatus is connected to the subscriber's line by means of the switch 10. Interrupted ringing current operates relay A, and each pulse causes sluggish magnet B to pull up and rotate the switch arm 40 one step. The switch 51 is set to bridge relay C across the loop after a predetermined number of pulses, thus simulating the reply of the subscriber, whereupon the ringing current is replaced by direct current. Relay C energizes and connects up sluggish relay D, which in turn connects up buzzer J to indicate to the calling subscriber that the recording apparatus is ready to receive his number. Successive trains of dialled impulses are repeated by relay C to magnets N, 0, P, Q which control the setting of the type-wheels 102, sluggish magnet E being energized during each train and then falling back to advance the sequence switch 72, which directs each impulse train to the appropriate magnet. Relay D also closes the circuit for relay G of a pair of sluggish relays G, F which energize alternately, G connecting up F and F disconnecting G. A ratchet wheel 183 is advanced one step at each energization of relay F, and after a predetermined time sufficient for the dialling of the maximum number of digits by the calling subscriber, a pin 186 on a wheel 185 geared to the ratchet-wheel 183 closes contact-springs 187, whereupon magnets K, U energize and lift the platen roller 120, causing the number exposed on the type-wheels 102 and also the time and date to be printed on the paper strip 131 by means of an ink-ribbon 194. A bushing 226 on the shaft of the platen roller 120 operates contact-springs 70, energizing) release magnets H, I to restore the switches 40, 72, whereupon relays C, D fall back in turn. Buzzer J is disconnected, and the circuit of relays F, G is opened. Magnets E, U release and the platen roller 120 returns to its original position, and in doing so, its end 227 closes contact-springs 119 for an instant, energizing magnets M, S to withdraw the holding pawls of the type-wheels and allow their return to normal. A pinion 128 secured to the shaft of the platen roller 120 by a one-way clutch moves over a rack 129 and causes rotation of the platen roller during the return movement, feeding the paper strip 131 forward. A circuit is also closed at springs 119 for magnet T which drives the ratchet-wheel 193 one step to wind the ink-ribbon 194. When the right-hand spool becomes completely wound, a post 212 is lifted to close contact-springs 208, whereupon relay W energizes and moves armature 213 to the right, transferring the connections from magnet T to magnet L to cause the ribbon to be wound back on the left-hand spool. ' The post 212 associated with this spool controls relay V in a similar way to move armature 213 to the left. The calling subscriber may hang up as soon as he hears the buzzer tone cease. The apparatus may be modified so that he may hamg up immediately after dialling by arranging that this shall effect reversal of current over the called loop to initiate the printing operation..The relays P, G and the gearing they control are then dispensed with, and a polarized relay X, Y, Fig. 3, is connected in series with relay C to respond to the reversal of current and close contact-springs 244 which perform the functions of the springs 187.