Patent GB-422421-A (GB)
Title: Improvements in or relating to multiplying machines
IPC: G06F7/46
Filed: 1933-07-11
Abstract: 422,421. Calculating -apparatus. BRITISH TABULATING MACHINE CO., Ltd., Victoria House, Vernon Place, Southampton Row, London. July 11, 1933, No. 19687. Convention date, July 12, 1932. [Class 106 (i)] Relates to a machine in which multiplication is effected by one of a plurality of multipliers in accordance with the size of the multiplicand. The invention is particularly adapted for use in commercial undertakings such as an electricity supply or other utility company wherein charges are based on one rate for all quantities consumed up to a limiting value and on another rate for the surplus consumption. Additional rates may apply in cases where there is provided a range of limiting values. The machine shown is of the record card controlled type and is generally similar to that described in Specification 405,031 ; such a machine is provided with a number of the usual multiplicand registers, an inverting or complementary register, multiplier relays, right and left hand accumulators, card feed section, impulse emitters, cam operated contacts, and the usual successive column punching machine. In addition manually set means are provided for entering the multipliers and limiting values. The general manner of operation will be understood from the diagram, Fig. 8. The machine reads from the record card the amount of the present and past meter readings ; the present amount is entered into five registers MC-1 to MC-5 and the old amount is entered in register 1VC. The reading out mechanism of the register 1VC is then connected to the registers MC and the complement added to those registers which then contain the amount (64 KWH) consumed. The operator sets up the various rates, say 9 c, 8 c, 7 c, and 3c on multiplier registers MP-1 to MP-4; he also sets up the limiting values, say 20 KWH, 50 KWH, and 100 KWH on registers CRO-1 to CRO-3, and sets up on registers TPRO-1 to TPRO-3 total price values (i.e. 180, 420, 770) corresponding to the limiting consumption values. During the operation of the machine the amounts in the registers CRO-1 to CRO-3 are read out and the complements thereof entered into the registers MC-3 to MC-5 to obtain a series of differences certain of which are true amounts and others complements. The machine proceeds to test the registers to ascertain which has the smallest real amount (MC-4). As a result the machine selects the related register TPRO-2 and enters the product thereon into the right hand accumulator RH ($4À20). The machine then selects the multiplier for the remainder obtained in the register MC-4 and initiates a multiplying operation, the product being entered in the right and left hand accumulators RH, LH. The amount in the RH accumulator is then transferred to the LH accumulator and the final amount ($5À18) together with the consumption which has been entered therein is then punched on the record card. The manually set registers are shown in Figs. 3, 4 and 5 ; those for the rates and price values have each a knurled wheel 291 carrying a pair of conducting brushes 295 for co-operation with nine conducting studs 293 and a conducting segment 294. The limiting value registers are the same except that ten conducting studs 293a are provided instead of nine. The wheels in each register are held in set position by a spring detent 292.