Patent GB-405030-A (GB)
Title: Improvements in or relating to mutiplying machines
IPC: G06F7/46
Filed: 1932-07-29
Abstract: 405,030. Statistical-apparatus. BRITISH TABULATING MACHINE CO., Ltd., Victoria House, Vernon Place, Southampton Row, London. July 29, 1932, No. 21487. Convention date, July 30, 1931. [Class 106 (i).] In machines for effecting multiplication by entering the factors into a multiplicand and a multiplier register and controlling thereby the operation of a multiplying mechanism to obtain the product as described in Specifications 307,025, [Class 106 (i), Calculating &c.], and 358,105, means are provided for performing a series of successive multiplications automatically. The machine is useful for dealing with transactions involving discount rates and operates in successive stages to obtain at each stage a difference, constituting a net amount, between a gross amount and the product of a gross amount and a rate. For this purpose the multiplier register is formed in a plurality of sections each arranged to receive a separate discount rate and each section together with the multiplicand register controls the multiplying mechanism. At the end of the first stage of the operation the multiplicand register is reset automatically and the product obtained during the first multiplication process is transferred thereto and a further stage of operation initiated to obtain the product of the new setting by the second discount rate, and so on. Finally the product register is reset after the product has been read out and recorded. To avoid the necessity for subtraction operations to obtain the net amount a translating mechanism is provided to convert the discount rates into their complements and to effect the multiplication by the complements so obtained. The machine shown deals with perforated cards punched with the factors of a computation and is provided with a card handling and punching section similar to that described in the above mentioned Specifications. Commutators and impulse emitters. Instead of can contacts the present machine utilises a circuit timer 120, Figs. 5 and 9, comprising an insulated cylinder with conducting segments co-operating with a row of brushes 121. The operation of the circuit timer is under the control of an electromagnet 130 the armature of which co-operates with the pawl 128 of a one revolution clutch on the main drive shaft 100 to drive a Geneva wheel 124 and gearing 123, 122. The main shaft 100 carries a number of brushes each co-operating with a number of conducting insets on segments 132, 133, and 134 (see circuit diagrams) of insulating material forming a set of three impulse emitters. Factor registering devices. These mechanisms comprise counters of the usual form with reading out commutators and clutch-operated resetting means. The multiplicand register, Fig. 3 has two commutators 102 and the counter magnets 210, Fig. 12c are connected to the contact c of triple contacts 212 a, b, c or double contacts 213 b, c as shown controlled by a relay 216. The number of triple contacts depends on the number of denominations in the multiplicand and the contacts a thereof are connected by leads 214 and plug connections to the reading brushes 172, Fig. 12a. The multiplier register DC, Fig. 12a, is divided into three sections each corresponding to a separate discount rate with reading out commutators 102 for the units and tens digits. The units commutators 102 in addition to the segments for the digits 1 to 9 have segments for the zero position of the brushes. The contacts of the units segments are connected to the leads 217 of the multiplier relays X1 to X9, Fig. 12b, in a complementary manner with respect to ten while those of the tens segments are connected to a line lower in number. Triple relay contacts 218 are provided in the tens leads 217 and these are controlled by relay coils 219 connected to the zero position contacts whereby the tens lines can be complemented with respect to ten when the units digit is zero. Multiplying mechanism. The relays X1 to X9 control sets of contacts connecting lines 230, Fig. 12b, with lines 232 RH, 232LH, the contacts being arranged in accordance with the values of the right and left hand digits of the partial products of the digits multiplied by themselves. The lines 232RH, 232LH extend to the right and left hand reading out commutators of the multiplicand register. The set of lines 230 are connected to the impulse emitter 132 and the common conducting brushes of the reading out commutators 102 MCR, MCL extend to the lines 233RH, 233LH of the accumulating section. The entry of amounts into the proper column is selectively controlled by relay contacts 234 ... 237, Figs. 12e, 12d. Circuit arrangement and operation. When the machine is to be set into operation current is supplied from the line 200 to the motor M by closing main switch 203 and a start key 204 is depressed establishing a circuit through a relay coil 205, the Geneva clutch magnet 130 and the card feed magnet 114. The circuit timer is set into operation and the cards are fed past the brushes 172, the multiplicand and multiplier being entered into the respective registers. The current supply for the reading out commutator of the multiplier register is provided through a line 220 and circuit timer contacts 221, 222, the other contacts 223 .... 227 being closed during later cycles. When these contacts are closed the appropriate multiplier relays X1 to X9 are energized and by reason of the impulses impressed on the emitter 132 on the closure of the timer contact 231 the appropriate lines 232RH, 232LH are rendered alive, the current passing through the reading out commutators in the multiplicand register MC and the lines 233RH, 233LH to the right and left hand sections of the accumulator, Figs. 12e, 12d, the entry thereto being controlled by the contacts 234 .. 237 of the relays controlled by the timer contacts 255, 256. At the proper time in the cycle timer contacts 238, Fig. 12d, are closed and the emitter 133 sends timed impulses through lines 239 to the reading - out commutators 102LH. At the same time contacts 241 are closed by energizing a coil 242 under control of timer contacts 258 thereby connecting the lines 239 to lines 240 so as to transfer the amount on the left hand accumulator to the right hand accumulator. During this cycle the multiplicand register MC is reset by energizing the reset clutch magnet 137 through timer contacts 243. The contacts 244 are then closed to energize relay coil 216 to shift the contacts c, Fig. 12c, so as to connect the magnets 210 of the multiplicand register to the lines 215 leading to the reading-out commutators 102RH. During this cycle contacts 245, Fig. 12e, close and through the impulse emitter 134 transmit the reading on the right hand accumulator to the multiplicand register. Timer contacts 247, 248 are then closed to reset the accummulators whereupon the multiplication by this new multiplicand and the second discount rate is effected. After the final product has been obtained the relay coil 216 is de-energized to disconnect the leads 215 from the magnets 210 and connect them to the punch control magnets 188 on the closing of contacts 250 by the energization of relay coil 251 through timer contacts 252. The magnets 188 are energized at the proper time through the impulse emitter 134 and the punching mechanism acts to perforate the card with the final result.