GB498400A - Improvements in or relating to record-card-controlled printing mechanism - Google Patents

Abstract

498,400. Typewriters &c. ; statistical machines. BRITISH; TABULATING MACHINE CO., Ltd. July 6, 1937, No. 18816. Convention date, July 7, 1936. [Class 100 (iv)] [Also in Group XIX] Hammer - impression arrangements.-In recordcard - controlled printing- mechanism comprising typecarriers which in some positions permit and in other positions prevent tripping of the associated hammers, means independent of the type-carriers is provided for automatically tripping all the hammers. The mechanism shown in the Figure comprises type-bars 12 provided with the setting-means described in Specification 425,838, and associated with hammers 17 co-operating with latches 18 having hooks 21 which co-operate with a bail 26, and with levers 23 adapted when zero-types are set to rock the hooks and thereby prevent printing of zeros. For controlling the printing of zeros, the latches are, as described in Specification 376,895, [Group XIX], provided with pivoted members 40 which can be set to trip adjacent latches, or can be set in inoperative position to split the machine. To permit of printing, for instance in an address, zeros which are normally suppressed by the splitting-members 40, additional mechanism under the control of a special perforation in the 11 position in the card is now provided. This mechanism comprises a bail 60 engaging the latches and connected to an arm 59 on a member 54 which is loose on the shaft 27 of the bail 26. An arm 50 secured to the shaft 27 carries a rod 51 to which are secured a pawl 52 and a cam 53 adapted to co-operate with a recess 55 in the member 54, and a pin 56 on a lever 57 respectively. Linkage 71, 73 in connection with the lever is normally restrained by the armature of a hammer-trip magnet controlled by the special perforation. When the special perforation is read by one of the upper brushes the circuit of the hammer-trip magnet is established by means of cam-contacts and a relay, and during the next cycle the typebars are set and cam-contacts close the circuit of the hammer-trip magnet. Thereupon, the linkage 71, 73 is permitted to rock the lever 57, the pawl 52 is moved into the recess 55, the shaft 27 is rocked, the bail 60 releases all the latches, and all the hammers are tripped. The hammer-trip magnet can be suppressed by throwing over a switch.