Patent GB-191093-A (GB)
Title: Improvements in or relating to key-board perforators suitable for producing punched tape for use in automatic telegraphy
IPC: H04L15/14
Filed: 1921-07-06
Abstract: 191,093. Creed, F. G., and Creed & Co., Ltd. July 6, 1921. Selective punching-machines.- Relates to a keyboard perforator for telegraph tape and comprises a machine, in which ta.pe is fed through a punch block carrying the punches and moved against combination bars selected and controlled by keyboard mechanism and a common resetting device. As described for punching tape on the Wheatstone - Morse system twenty combination bars d and ten spring-urged space bars e are arranged to slide axially on guides a and to be selected in predetermined arrangements by transverse key-levers m pivoted about fixed plates n and connected to horizontal key bars f. Movement of the combination bars is controlled by a pivoted resetting bar 1 connected by a rod 2 to a cam follower. The punch block is mounted on a spring blade 12 and connected by a rod 13 to a pivoted lever 14 oscillated from a cam and carries twenty punches 6 with heads 6<b> bent to engage a fixed withdrawing plate 7, and a back plate 10 having an extension 10<a> for the tape. A space stop bracket 16 is resilvently mounted in the frame and has ten vertical grooves 20, into which fit ten U-shaped plates 21 attached to the space bars e, and two transverse grooves 19, 19<a> in which slide a feed rake 22x with teeth 22b which engage the feed perforations in the tape. The rake is pivoted on a spring lever 24 spring held against a bell-crank 29 moved by a cam. Cams 27, 4, 15 control the movements of the feed rake, resetting bar, and punch block respectively and are carried on a sleeve 33 with a pivoted pawl loosely mounted on a driving shaft 34 having an integral ratchet wheel. On actuation of a letter or space key a one revolution clutch not shown actuated from a trip shaft v engages the pawl and ratchet to drive the cam sleeve for one cycle of opera tion. A spring key s actuates the trip shaft v and allows the tape to be fed forward without perforation. A combination key m<2> actuates a supplementary space stop (not shown) to eliminate the space between two letters. Normally the resetting bar 1 holds combination bars d and space bars e in their extreme, left position, Fig. 2. On depressing a key bar m a. bar f descends and holds against endwise movement the bar d corresponding to the letter and all space bars except the one corresponding to the letter, and further turns shaft v and couples up cam sleeve for one, revolution. The resetting cam 4 moves bar 1 to the inoperative position and frees the ends of bars d, e, thus selecting the punches and the spacing. The punch block cam 15 then moves the punch block carrying the tape, against the combination bars d and the perforations are made, the feed rake is disengaged from the paper and moves back on actuation of the spacing cam 27; the punch block is then moved to the left, the rake engages the perforations and the tape is positively fed forward under control of the spacing cam. For punching a tape on the five unit system five combination bars only are used and the space bars e and stops 21 are replaced by one fixed stop.