GB906429A - Improvements in or relating to data records and devices for recording and reading back coded information - Google Patents

Abstract

906,429. Statistical records. SVENSKA DATAREGISTER A.B. Feb. 2, 1959 [Feb. 12, 1958], No. 3646/59. Class 106 (1). Data, e.g. numerals, are recorded on a strip in a binary code as shown in Fig. 4, having four mark positions for each digit, a mark "S" always being present to control sensing and a check mark " C " being provided where necessary to make the number of marks odd. The white rectangles in Fig. 4 represent code positions where no mark is present. The recordings may be made in ordinary ink or radio-active or magnetic ink, a type face as in Fig. 5 being used. This approximates to the size of the type faces used for printing out invoices in cash registers or similar machines, and may be used instead. In Fig. 1 the code areas are in a different arrangement. Sensing.-If the marks are of ordinary ink e.g. from a typewriter ribbon, they are sensed photo-electrically. For this purpose the strip is fed over a table T, Fig. 8, and the image of the recording is thrown on a matrix of photocells FS, FC and F1-F8, there being a similar column for each digit column of the record. There is also a photo-cell FR for a mark R adapted to reset the reading circuits before the associated columns of data are sensed. Light from the record passes to the photo-cells through slots B in a mask which prevents interference between positions. The photo-cell signals are amplified in amplifiers AR, AS, AC and A1-A8, Fig. 6. The outputs from amplifiers AC, A1-A8 pass via And gates NC, N1- N8 to flip-flops VC, V1-V8. The outputs from amplifiers AS and AR control a flip-flop VS connected to an impulse generator G. In operation, the resetting mark R comes under the photo-cell just before the other marks reach sensing position and the flip-flop VS is reset. This resets all the other flip-flops VC, V1-V8 to cancel the value previously sensed. When the control mark S reaches sensing position, the signal from photo-cell FS sets flip-flop VS causing the generator to give a pulse which opens the gates NC, N1-N8. The marks C and 1-8 reach their sensing positions slightly after the control mark S and any marks present set corresponding flip-flops VC, V1-V8.