GB381600A - Improvements in or relating to printing mechanism - Google Patents

Abstract

381,600. Typewriters &c. BRITISH TABULATING MACHINE CO., Ltd., Victoria House, Vernon Place, Southampton Row, London.-(Assignees of Bryce, J. W.; Bloomfield, New Jersey, U.S.A.) July 9, 1931, No. 19791. Convention date, July 10, 1930. [Class 100 (iv).] Relay type-wheel actions; case-shift mechanism.-In actions comprising a cyclically movable carrier for pivoted type-members, and a selecting-device for causing a type-member to rock for impression when passing the platen, the types are movable along the type-members for case-shift under the control of an auxiliary selecting-device. The apparatus shown in Figs. 1 and 2 is controlled by Hollerith cards and comprises, as described in Specifications 208,533 and 289,071, [both in Class 100 (iv), Typewriters &c.], a rotary drum 20 carrying rings of pivoted type-bars 23 which are selected for impression by means of hooks 27 controlled by magnets 24. Each type-bar is now provided with a slide 34 carrying four types 30 .. 33, and each ring of slides co-operates for case-shift with a stop-arm 35. The stoparms are mounted on a shaft 35a and are connected by springs 41 to a bail 40 which is rocked by a cam 37 on the drum, each arm having notches 42, 43, 44 for engaging a stop-finger 47 normally engaging a latch 46 controlled by a magnet 45. When the selected type-bar is swinging for impression, the associated latch is released, and the stop-finger is caused to engage one of the notches or to miss all the notches as determined by the time at which the magnet is energized. Thereby, the stoparm is differentially positioned, and a cam 36 thereon co-operates with the sleeve on the selected type-bar to select one of the four types. The stop-arms may be arranged to shift the sleeves before the associated type-bars swing for impression. The types 30 are employed for numerals, and the types 31, 32, 33 for letters and zero. Numerals are represented in the cards by single perforations, and letters and zero by one of the perforations 0, 11, 12 and one of the perforations 1 .. 9, the perforations 0, 11, 12 controlling the magnets 45 and being read in advance of the perforations 9 .. 1 which control the magnets 24. Zero is represented by the 12 and 9 perforations, and to prevent zero from being entered as nines on the counters, the counter magnets 62 are in circuit with contacts 70 which are normally closed by the latches 46 but are opened when the magnets 45 are energized.