GB601355A - Improvements in or relating to printing telegraph receivers - Google Patents

Abstract

601,355. Printing telegraph receivers. CREED & CO., Ltd., and SALMON, R. D. Nov. 6, 1945, No. 29526. [Class 40 (iii)] A device for incorporation in a printing - telegraph receiver to adjust the timing of selector members with respect to the received impulses and which includes a cam released by the start element of a signal and operating to effect the connection of the selector member to a driving shaft by means of a ratchet clutch is described in its application to the telegraph receiver set forth in Specification 228,842, [Class 40 (iii)]. The cam 10 which is driven from the driving shaft by a friction clutch, is held in its stop position by the engagement of a lug 11 with one arm 13 of a pivoted detent lever 14 having a second arm 16 associated with a spring-biassed retaining lever 17 which assumes the position shown when the cam 10 is in the stop position. A latch member 20 which is held under a spring blade 27 secured to the arm 16 is moved to the right by pivoted levers 22, 24 when a lever 25 is actuated by the armature 26 of the receiving magnet in response to the start element of the signal. Lever 17 is rotated against the action of a spring 18 and the detent lever 14 rotates counter-clockwise under the action of a spring 19 to release the disc 10. Towards the end of a revolution, a roller 29 carried by the arm 16 is engaged by a second lug 12 and the lever 14 is rotated clockwise so that its end is again engaged by the lever 17. If the latch member 20 is in its right-hand position when the lever 16 is rotated, the end portion engages the top of the lever 17, the spring blade 27 being deflected. When the armature is moved to the left in response to the stop element of the signal, the end of the latch 20 drops into its normal position on the arm 16. Shortly after the commencement of the rotation of the cam 10, the lug 12 engages a roller 30, Fig. 4, mounted on the same shaft as a second roller engaging the inner curved surface of a lever 39 fixed on a shaft 40 carrying a lever 42, Fig. 7, operating a detent 44 which on release allows the pawls 7 to clutch the selector member 2 to the driving shaft. The roller 30 which is adjustable in a path concentric with the disc 10 is carried by an arm 31 pivoted in a frame 32 which is adjustably secured to a fixed arcuate frame member 33. The frame 32 carries an index mark for association with a scale on the frame 33, Fig. 5 (not shown). Specification 487,291 also is referred to.