GB725690A - Improvements in or relating to printing mechanisms - Google Patents

Abstract

725,690. Selective printing machines. BRITISH TABULATING MACHINE CO., Ltd. Feb. 16, 1953, No. 4260/53. Class 100(4). In a printing mechanism in which the characters are formed by the selective operation of a number of printing elements, the same elements, e.g. five segments 2 occupying the width of a character are selectively and repeatedly operated as the paper is advanced through the height of the character. so as to form the whole character row by row. Impression is made by the segments 2 through an ink-ribbon 25 on to the paper carried round a platen 18. If, e.g. it is required to print a letter I firstly, the central three segments are operated, then for five impressions, the central segment only, and finally the central three segments are again operated. These operations are controlled by the operation of a character relay from the sensing of perforations in a record card and by a master commutator 53 having studs 56 representing characters. This commutator is rotated step-by-step in synchronism with the platen and causes the operation of the required element printing magnets 9. The operation of the particular magnets 9 attracts armatures 10, moving rods 11, cranks 12, rods 13 and segment releasing latches 7. The segments released effect printing by the effort of adjustable springs 19 and are restored by a rotating cam 24. There may be a number of groups of segments 2 one group for each column to be printed. The matter to be printed is sensed from perforations in a record card which cause operation of a group of six storage relays which are selectively operated under control of a coding drum commutator and six gas-filled tetrodes. The contacts of the storage relays are connected to translating means comprising a network of relays, R7(A)- R7(Z), R7(1)-R7(0) (R7(A)-R7(N) (shown only, Fig. 6), whose contacts complete circuits from the master commutator 53 to the printing magnets 9. Paper carriage.-The platen 18 is mounted on plates 43 secured to plates 47 by slotted fixings 42 to enable horizontal adjustment of the platen in regard to the segments 2. Similar fixings between the plates 47 and the machine frame allows vertical adjustment. Specification 679,944, [Group XIX], is referred to.