Patent GB-731342-A (GB)
Title: Improvements in or relating to digital data storage systems
Inventor: WILLIAMS FREDERICK CALLAND
IPC: G06K7/10
Filed: 1950-04-05
Abstract: 731,342. Digital electric calculating apparatus; statistical apparatus. NATIONAL RESEARCH DEVELOPMENT CORPORATION. March 15, 1951 [April 5, 1950; Nov. 10, 1950], Nos. 8613/50 and 27564/50. Class 106 (1). An information storage system comprises a plurality of stacked sheets or cards bearing information represented by areas whose lighttransmitting capacity differs from other adjacent regions, and means for moving any selected card relatively to the remainder of the stack to position information bearing 'areas thereof for inspection by associated optical scanning means. In the described embodiment a library of cards 15, Fig. 3, bearing representations of sub-routines for an electronic calculating machine, is controlled by the machine via a select mechanism 31. A selected card is displaced relative to the stack by an amount sufficient to bring data-representing perforations 11, Fig. 1, opposite rows of inspection holes 14 in the remainder of the stack, so that the selected data becomes available for inspection. The beam of a C.R.T. 17 placed against the stack of cards, is scanned along the rows of inspection holes successively under the control of X and Y time bases 21, and the signal, modulated in accordance with the punched data on the selected card, is picked up: by a photo-cell 22 and; after amplification, fed into the main electronic store 25 as a binary series-mode pulse train. A similar pulse train emanating from the store 25 initiates the selection of a card. By means of a staticisor 33 the instruction word effects selective energization of a series of relays 32 in accordance with its binary representation and each relay 32; Fig. 7, energized rocks an armature 64 which, through wires 57, pulls a pair of slotted members 60 arranged with their slots in staggered relationship so that one or the other member has its slots 61 or projections 62 opposed to projections 68 on a co-operating member 67 .according to whether or not the associated magnet has been energized. After the setting of the members 60 the member 67 is raised by motor-driven cam means 37, Fig. 3, and a pattern of members 60, Fig. 4, corresponding with the instruction is moved upward to lift all the cards in the stack with the exception of the card 10 bearing a notched representation of the corresponding binary number along its lower edge. The data cards, Fig. 1, are separated by interleave cards, Fig. 5, which are-held stationary. The alignment of notches 49 serves to check that the cards are correctly placed in the stack. The data perforations 12 may be extended to meet the inspection holes 14 and the inspection holes may be extended horizontally to form a continuous slot. In another embodiment (Fig. 10, not shown) the notched members 60 are replaced by iron bars selectively positioned by electromagnets operating in conjunction with a permanent magnet. A mechanical scanning arrangement comprising a constant light source and a rotatable apertured disc or rotatable mirror device, may be employed. The cards or sheets may be of paper, cardboard, sheet metal, or transparent material prepared photographically. Specifications 645,691, 657,591, 682,156, 705,474, 705,479, 707,634, 707,635 and 731,341 are referred to.