Patent GB-457136-A (GB)
Title: Improvements in or relating to multiplying machines
IPC: G06F7/46
Filed: 1935-05-23
Abstract: 457,136. Calculating - apparatus. BRITISH TABULATING MACHINE CO., Ltd., and CAMPBELL, C., Victoria House, Vernon Place, Southampton Row, London. May 23, 1935, No. 15071. [Class 106 (i)] In a multiplying- machine having mechanism for registering a standard series of multiples of the multiplicand as described in Specification 456,367 is provided with means whereby any of the multiples can be entered into a product accumulator additively and certain of the multiples can be entered subtractively and multiple selecting means automatically operable to select, in accordance with each digit of the multiplier, a multiple or a pair of multiples whose sum or difference is equal to the product of the multiplicand and the multiplier digit. In the preferred arrangement two product accumulators are provided and a pair of multiples is entered concurrently. The invention is described as embodied in a record card controlled machine as described in Specification 405,031. The machine as shown diagrammatical in Fig. 1, comprises a motor M driving an AC-DC generator, a card feeding section CF, a punching section P, multiplier and multiplicand registers MC, MP, a pair of product accumulator sections LP, RP and sets of relays CS, CR and Z. The registers as shown in Fig. 2 comprise groups of slides 50 supported by spring-controlled levers 48 carried by a cross-head 40 slidable on rods 41 and operatively connected to levers 43 co-operating with cams 46 on a shaft 32. The movements of the slides are controlled by pawls 54 and latches 55 connected to the armatures of the register magnets MC, MP. The rotation of the shaft 32 is under the control of a one revolution clutch 34 electromagnetically operated. Each multiplicand slide 50 carries six brushes 57, three on each side, and each of which co-operates with a common bar 58 mounted in an insulating member 59 and with a set of ten segments 60 in an insulating member 61. The multiplier slides are only provided with three brushes, two of which co-operate with ten segments and a common bar, while the third co-operates with a zero segment and a corresponding bar. In this arrangement, the series of multiples is once, twice, five-times, and ten-times the multiplicand and the upper group of segments in the multiplicand slide constitutes a reading-out mechanism for five-times the multiplicand, the lowest section constitutes a reading-out mechanism for twice the multiplicand, and the centre groups comprises two reading-out mechanisms for once and ten-times the multiplicand. The electrical circuit arrangements and an example of use of the machine are described in the Specification. In a modification, instead of employing two product accumulators only one product accumulator is provided, the circuit arrangements, relays, and registers are modified accordingly. In another modification, the machine calculates twice, four-times, and fivetimes the multiplicand and selects the multiples for entry into two accumulators. If the invention is applied to keyboard machines, the register slides may be arranged horizontally, each being provided with a single abutment co-operating with a set of key-controlled stops. A start key would be depressed to energize the register clutch magnet and the machine would operate to calculate the product as described with respect to the card controlled machine.