Patent GB-467604-A (GB)
Title: Improvements in or relating to printing mechanism
IPC: G06K15/04
Filed: 1935-12-21
Abstract: 467,604. Typewriters &c. BRITISH TABULATING MACHINE CO., Ltd. Dec. 21, 1935, No. 35432. Convention date, Dec. 22, 1934. [Class 100 (iv)] [Also in Group XIX] Relay type-bar actions. -In selective - printing mechanism comprising a reciprocating group of type-carriers, each typecarrier is associated with a hammer which is selectively operated when the required type is passing the printing line, impression being effected without interrupting the movement of the type-carrier. Provision may be made for controlling the printing of zeros and for splitting the machine. In the record - card controlled mechanism shown in the Figure, type-bars 10 carrying types 18 are detachably mounted in a cross-head 12 provided at each side with a rod which passes through guides 21, 23 and is provided with rollers 25, 26 co-operating with cams 27 on a shaft 28. The cams cause the cross-head to reciprocate once during each card-feeding cycle. To permit of detachment, the type-bars are arranged to fit over bevelled plates 14 secured in slots 13 in the cross-head, and a detachable top 16 is provided for the cross-head. Each type-bar is associated with a hammer 53 which is pivoted on a rod 42 and engages a lug 55 on a bell-crank 41 also pivoted on the rod, a hammeractuating spring 43 being connected to a rollerlink 44 which engages any one of a series of notches 46 in the bell-crank. The set of springs can be adjusted by means of a handle in connection with a bar 48 which is suspended from a shaft 49 and co-operates with the links 44. The bell-cranks 41 have hooks 40 co-operating with latches 38 on a frame 33 which is slidable on the rods 20 and is provided with a roller 34 co-operating with a cam 35 formed with rises 37 for reciprocating the frame, the upward stroke in each reciprocation occurring when the corresponding types 9 .. 1 are passing the printing line. The latches 38 co-operate with stops 60 having latches 61 in connection with the armatures 63 of magnets 64 which are in circuit with the card-brushes LB. When a card-perforation is read, the corresponding type is approaching the printing line, the frame 33 is moving upwards, the appropriate stop 60 obstructs the latch 38, the bell-crank 41 is released, and the hammer is permitted to strike the selected type. The hammer-head 56 is pivotally mounted to allow passage of the remaining types. During return of the cross-head 12, a hammer-retracting bail 69 is operated by means of a rocking arm 68 in connection with a bellcrank 66 operated by a cam 65. For controlling the printing of zeros to the right of the highest significant figure, the latches 38 are associated with forked members 75, and the cam 35 is formed with a rise 37a for raising the frame 33 abnormally when the zero types are passing the printing line. The members 75 are loosely pivoted on a rod 76 and are each formed with a lug 78 extending over the adjacent member of higher denomination. When the zero types are passing the printing line, the abnormal raising of the frame 33 causes the latches 38 that have been previously tripped to rock the associated members 75, this movement is transmitted to the remaining members and latches, and the hammers are thereby released to print from the zero types. The zero perforations at the left of the highest significant perforation are read ineffectively by the brushes, since the rise 37a causes the latches 38 to move past the end of the stops 60. For splitting the machine, the member 75 associated with the highest type-bar in each bank is moved to the left by means of a finger-piece 79 to position the lug 78 over a depression in the adjacent member.