Patent GB-1177755-A (GB)
Title: Impulse Transmitter for Telephone and Telewriter Installations
IPC: H04M1/274
Filed: 1967-01-12
Abstract: 1,177,755. Repertory diallers. TELE MASTER G.m.b.H. 12 Jan., 1967 [12 Feb., 1966], No. 31151/66. Heading H4K. A repertory dialler has a magazine of profiled members, each profile representing a frequently wanted directory number, an array of pushbuttons corresponding to the profiled members such that actuation of a push-button releases a profiled member from a stored position to an operative position from which a motor-driven mechanism senses each digit representing portion of the profile as it returns the profiled member step-by-step to its stored position, each sensing operation causing a conventional finger wheel impulse mechanism to be wound and released according to the digit represented. The profiled members representing directory numbers may comprise radially profiled plates, Figs. 10 and 11, not shown, or may be assembled from rods 51, Fig. 12d, slotted transversely so as to be slid sideways into a magazine 144, Fig. 12a, having a transverse projecting lip engaging an appropriately chosen slot in each rod so as to hold the rod in place with a length projecting corresponding to a particular digit. Each rod has thirteen transverse slots, the first giving the maximum extension, merely filling initial unwanted digit positions in the magazine and acting as an abutment to define the starting position from which the repertory dialler mechanism senses subsequent rods. The second slot, giving the next but one maximum extension is employed, after a digit group such as an area code, to halt the dialler for subsequent manual release should conditions warrant continuing. The third slot, giving a further unit decrease from maximum extension, provides a predetermined pause between digit groups the mechanism cycling as it would for sending a digit. The remaining ten slots in each rod represent digits 0 to 1 as the corresponding extension decreases. The same functions are provided by the radial extensions of profiled plates in the alternative form of profiled members, such plates being mounted in the dialler to pivot about a mounting bar so as to drop pivotally to an operative position on actuation of a corresponding key. When the profiled members comprise rod filled magazines they are mounted in vertical slideways. One such magazine is shown at 22 on Fig. 3 where it is in the stored position in which a nose 21 projecting from the magazine engages a latching bar 12 controlled by the associated pushbutton 5. When the push-button is pressed the bar 12 is moved downwards to a latched position in which a switch 18 is operated and separately latched by a rod 30 and latch bar 35, the magazine being released along with a ratchet quadrant 32 to fall to a position in which the furthest extending rods 36 if any, or the nose 21 of the magazine, rest on a transversely extending bracket 37. In this position the first rod representing a digit lies in line with a transversely extending sensing bar 44 mounted on a carriage 43. The switch 18, after a delay sufficient to allow the magazine to fall into position, starts a motor which over gears 56, 55 and 42 drives the carriage 43 which moves until the sensing bar strikes the first digit rod. The extent of this movement is used to wind the finger wheel shaft of an impulse transmitter 81, as shown in Fig. 4, where the motor 49 over friction drive 58, 57 and gears 56, 55 drives a shaft 69 on each end of which are pinions 42 which mesh with racks on the carriage 43. The gear 55 is fast with a hollow shaft 73 carrying a pin 75 working in a helical track 74 in a sleeve 66 fitted over the hollow shaft 73. The sleeve 66 rotates with the carriage drive shaft 69 a pin 71 projecting from which engages a slot 72 in the sleeve. As a spring 68 presses the sleeve 66 to the right, drive from gear 55 is transmitted to the shaft 69 and pinions 42 until the carriage is halted by the digit rod encountered by the sensing bar 44. Shaft 69 is then held fast and continued rotation of gear 55 drives pin 75 along helix 74 to propel the sleeve 66 to the left until it strikes a frame 61, pivoted on shaft 63, which deflects to operate switch 59 and reverse the drive from motor 49. The helical cam 77 on the shaft 69 advances the frame 61 towards the sleeve 66 to an extent dependant upon the value of each digit suit. The smaller the digit the less the distance advanced by the frame before the sleeve 66 starts its motion and consequently the greater the time taken before the device is ready to send the next digit. Each digit, therefore, takes the same time to transmit regardless of'its value. As shown in Fig. 5 the frame 61 has a latching arm 93 which engages behind a catch 91 to hold the reversing switch 59 operated. The catch 91 is shown in the released position as determined by a pin 92 on the impulse sender drive gear 86. The gear 86 is displaced to the extent of the required digit before the switch 59 is operated to reverse the motor, reversal of the motor releasing the impulse sender to transmit the digit. When the gear 86 reaches its home position it trips the latch 93 to release switch 59. The motor 49 now returns to forward drive for a further sensing cycle. As seen in Fig. 3, each reciprocation of the carriage 43 drops the ratchet 38 one tooth on advance and raises it on retraction so as to lift the magazine 22 and present the next digit rod to the sensing bar. When the last digit rod has been sensed the magazine 22 is lifted to its stored position, with its nose 21 latehed above the push-button release bar 12, and the ratchet quadrant 32 lifts the latch bar 30 to release switch 18 and stop the motor. The repertory dialler may sense a digit rod which calls a halt between digit groups. This is done by means of a trailing arm on the carriage 43 which normally moves far enough over a cam profile to return without effect but when the long digit rod demanding a halt is encountered the movement is so small that the profile is not cleared and return of the trailing arm operates a stop switch. The halted condition may be cleared by a push-button on the dialler which sets the dialler off on the next group. Alternatively a second button may be pressed to abandon the call and effect rapid restoration of the dialler. This latter operation blocks the sensing carriage in a position clear of the digit rods and allows the motor to cycle from forward to reverse on a short leash to operate a three-step lifting ratchet to restore the magazine to its stored position and restore the mechanism to standby.