Patent GB-854309-A (GB)
Title: Improvements in high-speed printing devices
IPC: G06K15/08
Filed: 1955-08-25
Abstract: 854,309. Typewriters &c. DIRKS, G. Nov. 23, 1956 [Aug. 25, 1955], No. 24420/55. Class 100(4) A multi-column printing apparatus comprises a type assembly having a set of type faces for each column arranged to form rows of similar characters constantly rotated to bring the type faces of each set successively past the printing position and storage device rotated at a speed of the type assembly multiplied by the number of columns and the stored signals of which are read out column by column once for each row of type passing the printing position. The read out signals in conjunction with time base signals being arranged to provide a signal in each column in which the character for the row then passing the printing position is to be recorded to effect printing thereof. In the embodiment of Figs. 1, 2 a cylindrical type assembly 3 having identical circumferential columns of characters 51-N is constantly rotated by a motor 11 which also rotates a magnetizable signal storage member 13. Impression is effected by momentum on a sheet 30 by a ribbon 29 on actuation of impression members 23 by an operating roller 4 after the appropriate members 23 have been released from spring armatures 21 by operation of appropriate magnets 20. Time base signals for the magnets 20 of each column are arranged circumferentially around the member 13 and are sensed sequentially for each column by a head 14 while the data to be recorded is similarly arranged circumferentially for sensing by a head 15. The signals from the head 14 are fed through an amplifier to a counting tube which sends timed pulses to a controlled amplifier which also receives signals from the head 15. The arrangement is such that when the signals from the heads 14, 15 coincide a tube is fired which operates a magnet 20 to which it is connected by a distributor rotating synchronously with the member 13. For each row of charcacters reaching the printing position a complete cycle of sensing of the data of the member 13 is effected, to provide signals to the magnets 20 to release the members 23 of those columns in which the character of the row is to be recorded. Immediately at the end of the cycle a rib 61-N on the roller 4 causes the released members 23 to effect impression. After each cycle an addition signal is fed to the counting tube by the momentary closing of contacts 34 so that during the next cycle the counting tube will produce pulses at the time signals corresponding to the next character row are being read by the head 15. In modified printing mechanism Fig. 12 the type faces for each column are mounted on separate wheels 108 secured to separate holders 109 connected by springs 110 to arms 111 on a shaft 112. Springs 119 urge the holders 109 clockwise so that gears 113, 114 fully engage and the type faces can be rotated together from a shaft 118. Upon counter-clockwise movements of the arms 111 a stop 121 is engaged and the type face strikes under momentum without completely disengaging the gears 113, 114. A spring blade 122 acts as a brake to the type carrier and to align it for impression it may be provided with a shaped edge to enter between teeth on the gear 113. In embodiments such as this the column magnets 127 are energized in rapid succession and to allow for the successive printing of the characters each row extends slightly helically on the type assembly. A modified impression mechanism Fig. 29 comprises a member 311 mounted on a spring blade 303 normally held by a latch 305 out of contact with a toothed wheel 300 rotating in synchronizm with a type assembly 297. When a solenoid 308 is operated similarly to the solenoids 20 to unlatch the blade 303 a pawl 302 is engaged by the wheel 300 and as it jumps off a tooth thereof impression results under momentum, the blade becoming relatched. Various modified control circuits are described for use with either embodiment when characters other than the digits of Fig. 1 are required. When additional characters are used they are arranged in groups on the type carrier and selection of group by a timed signal is followed by another timed signal to select a character from that group. In place of magnetizable storage 13 other erasible storages such as a matrix of magnetic cores, flip-flop chains, a plurality of multi-stage tubes, or sets of capacitors may be used. The provisional specification describes and illustrates diagrammatically other basic ways of carrying out the mechanical printing and of circuits for the control thereof by a reading of stored data. It further states that the printing apparatus may operate from signals derived from punched cards or tapes. Specifications 786,021 and 786,041 are referred to.