GB709726A - Improvements in or relating to printing telegraph apparatus - Google Patents

Abstract

709,726. Typewriters &c. CREED & CO.. Ltd. April 25, 1952 [April 27, 1951], No. 9868/51. Class 100 (4). [Also in Group XL (b)] In page-printing telegraph apparatus comprising means for imparting a series of letter-feed movements to a carriage and trip means operable to cause said carriage to be returned to its initial position, a release member controlled by said carriage and operating to actuate said trip means after a predetermined number of letter feed movements and mechanically operable resetting means for restoring said trip means to its inoperative condition, means is provided for delaying the operation of said resetting means until the carriage has completed at least a part of its return movement. The invention is shown as applied to a Creed No. 7 Printer in which a rack 1, Fig. 1B, attached to the carriage is moved by a pinion 2 carried by a spring drum 3 secured to a ratchet wheel 4 engaged by a feed pawl 5 and a retaining pawl 6, the pawl 5 being oscillated by a lever 10 connected to a lever 9 carrying an arm 8 reciprocated by a cross-head 7 for each printing operation. When letter-feed is to be suppressed a bar 12 depresses the arm 8 so that the movement of the cross-head is disconnected from the lever 9. To effect carriagereturn the operation of an arm 14, Fig. 1C, rocks a lever 15 so that a bar 16 oscillated by the cross-head 7 rocks a lever 18 which disengages the pawls 5, 6 and allows the carriage to return under the action of its spring drum. The lever 18 is latched by a detent 19 which is released when the returning carriage engages an upstanding projection 20. The drum 3 is provided with an adjustable sector 32 carrying a projection 31 and can be set to operate the carriage return arm after a predetermined number of letter-feed movements. At the specified position, the projection 31 engages a pivoted lever 34, Fig. 2, so that its upper end is moved clear of a turnedover projection on a release lever 37 which moves downwards under the action of a spring 36 and lever 41 so that it engages the lever 15 which controls the return of the carriage. As the drum rotates backwardly the projection 31 engages the uplifted end of the lever 41 and moves the bar 37 upwardly until it is relatched by the end of the lever 34.