Patent GB-366471-A (GB)
Title: Improvements in keyboard-operated telegraph apparatus
IPC: H04L17/04
Filed: 1930-10-23
Abstract: 366,471. Selective punching machines. CREED & CO., Ltd., SALMON, R. D., and KIRK, S. E., Telegraph Works, Croydon. Oct. 23, 1930, No. 31847. [Class 31 (ii).] A keyboard for the transmission of signals or the perforation of tape according to the code elements operates in conjunction with a common driving shaft from which a cam sleeve effecting the signal transmission is driven at a slower rate than a sleeve operating the strip perforating mechanism. When tape perforation is effected simultaneously with signal transmission, the keyboard is operated at the slower rate corresponding to the speed of signal transmission. The keyboard is similar to that described in Specification 264,907, [Class 31 (ii), Punching and perforating machines &c.]; and a typical key-lever 1 moves one or more combiriation bars 2 to engage corresponding fingers 3 .. 7 and a sixth bar 8 which, during a revolution of the cam sleeve 9, cyclically operate a lever member 65 engaged by arms 67, 68 passing round a spring contact blade 10 which is moved against one of two contacts 11, 12. Additionally, as described in Specification 264,907, a locking bar 13 and a send-receive switch lever 14 are operated from the cam sleeve 9. Each bar 2 is also formed at one end with a notch engaging a member 15, rotatably mounted on a fixed shaft 16, and providing in one position of the corresponding bar an abutment for an associated punch rod 47. The depression of any key 1 operates a universal bar 25 connected to a pivoted member 26 with slotted extensions 27, 28 engaging two members 29, 30 mounted in leaf-spring 31, 32. The members 29, 30 are formed with shoulders 33, and when raised engage pivoted clutch detents 34, 35 arranged to release the ca:n sleeves 9, 17 respectively for a single revolut ion, during which cams 38, 39 move the members 29, 30 out of engagement with the arresting detents. The pawl and ratchet mechanisn, may be of the type described and shown in Specification 260,758, [Class 80 (ii), Gearing, Variable-speed &c.]. The selection of the mechanism for signal transmission or tape perforation is effected by a member 40 with notches 41, 42 at right-angles and rotated by a wing nut 43. In the position shown, the rod 29 is maintained in a position such that its shoulder 33 cannot engage the member 34 to release the detent 36 of the signal transmission mechanism. The cam sleeves 9, 17 are driven independently and at different rates by gears 20, 23 meshing with gears 21, 24 of different sizes on a constantly rotating layshaft 18. Perforating arrangements. The code bars 2 when moved to the left rotate the corresponding abutment members 15 out of the operative position with regard to the punch rods 47. The rotation of the cam 17 oscillates a frame 44 on a shaft 45 to bring the tape 48 against the rods 47 which perforate the tape according to the selective positioning of the abutment members 15, and against a rod 50 which punches a feed hole. During the punching movement of the frame 44, a ratchet wheel 53 is moved under. pawl 54 connected by a spring 56 to a reversing pawl 55, normally maintained out of engagement with the wheel 53 by an inward projection 57<1> on a reverse-feed lever 57. During the return movement, the operative punch rods are retracted from the tape by a fixed member 49, the inoperative rods being moved to their normal positions by a member 49<1> fixed to the frame, and the wheel 53 being moved one step by the pawl 54. When a backward feed of the tape is required to correct a previous set of perforations, the depression of a key 58 operates a bar 60<1> to move the members 15 out of punching engagement, and a bar 60, connected to the universal bar 25, to release the perforator cam sleeve for a single revolution. At the same time the forward-feed pawl 54 is raised out of engagement with the wheel 53, and during each return movement of the frame 44, the pawl 55 moves the feed-wheel 53 a step in the reverse direction. To provide for the feed of blank tape the depression of a further key 61, Fig. 1, operates members 62, 63 to raise an extended part 64 liberating the clutch detent 35 for free rotation of the cam sleeve 17 whilst the key 61 is held depressed.