GB703270A - Improvements in or relating to printing apparatus for statistical machines - Google Patents

Abstract

703,270. Record-controlled printing-machines. POWERS-SAMAS ACCOUNTING MACHINES, Ltd. Oct. 3, 1951 [Nov. 29, 1950], No. 29278/50. Class 100 (4) In a record-card-controlled printing machine the characters required for printing in each column are disposed around the peripheries of a number of type-wheels 4, 5, 6, 7 mounted on a carriage 13 which is moved to position one of the type-wheels below a printing platen 22; simultaneously the type-wheels are rotated to selectively position a character in line with the platen. This arrangement enables the apparatus to operate at a high speed, of the order of 400 lines per minute. Sensing of the record cards effects a displacement of one or two stops 2 arranged in a stop basket similar to that described in Specification 26896/13, [Class 100 (iv)], and according to the numeral or alphabetical code received. The first part of a two-hole code sets up particular stops A, B, O and the second part sets up stops 1-9. Stops A, B, O after displacement project into the path of a depending lug 17 on the type-wheel carriage 13, which after the sensing operation, is allowed to move leftwardly under the pull of a spring 42 under the control of a restoring bar 18 operated by linkage 36, 37, follower 40 and a cam 41 secured on a machine-driven shaft 31. Stops A, B, and O allow wheels 6, 5 and 4 respectively to move into printing position, while if no stop 2 is raised e.g. in a single hole code the lug 17 is arrested by the restoring bar 18 itself whereupon the wheel 7 is below the platen. The Figure shows the type-wheels for each column and each wheel has ten characters which together comprise the alphabet, numbers, &c. All the wheels in each column are selectively rotated by a toothed selecting bar 14 whose spring-urged leftward movement is controlled by a depending lug 55 engaging with the nine right-hand stops 2 or a restoring bar 56, operated by linkage 57, 58, follower 59 and cam 60, in a similar manner to the bar 18. The cam 41 is shaped so that, as the carriage approaches a stop, it is decelerated ; rebound is avoided by making the springs 42 and 61 heavy in weight and light in pull. Aligning for impression.-Each carriage 13 and its selecting bar 14 halt just beyond printing position and are accurately retracted by pawls 44 and 63 mounted on angle members 46, 65 common to all columns and which engage notches 43, 62 in the carriages 13 and selector bars 14. The angle members 46, 65 are operated by linkages actuated by a cam on the shaft 31. Paper supports; platen impression arrangements.-A resilient platen 2 is supported by plates 23 carried by brackets 24 pivoted at 25 to the machine frame and is moved downwardly to press a paper strip P and an ink ribbon on to the type wheels to effect impression. The downward movement is effected by linkages 27, 28, follower 29 and a cam 30. To accommodate variations in the thickness of the type the carriages 13 are resiliently supported by a common plate 72.