Patent GB-345655-A (GB)
Title: Improvements in or relating to multiplying machines
IPC: G06F7/46
Filed: 1929-11-22
Abstract: 345,655. Calculating-apparatus. WESTERN ELECTRIC CO., Ltd., Bush House, Aldwych, London.-(Western Electric Co., Inc. ; 195, Broadway, New York, U.S.A.) Nov. 22, 1929, No. 35861. [Class 106 (i).] Multiplying-apparatus.- The principle of operation involves getting the product 10x+y, of two digits a and b and transmitting y impulses to the " units part of a registering device and x impulses to the " tens " part, the product being selected from a set of 9 discs representing a, 2a, 3a .. 9a by a brush corresponding with b, the discs being driven through two half-revolutions, in the first of which the " units " impulses are sent forward and in the second the " tens " impulses. If the digits occur in the tens, hundreds or thousands places obvious changes take place. Multiplication is effected by depression of the appropriate keys 103 in a multiplicand bank 101, Fig. 8, and a multiplier bank 102. In the diagrammatic Fig. 1 the keys appropriate to the multiplication of 4628 by 2016 are shown enclosed in a dotted ring. The means by which the product is shown by the register 110 comprise essentially nine " digit commutators " 108 and a distributer switch 109 with six brushes 166 .. 171 each moving over a set of ten terminals. The first four of the brushes 166 .. 169 are connected, each to each, to the four vertical banks of the multiplicand; brush 170 is peculiarly associated with the multiplier bank 102 ; and brush 171 with certain control discs 136, 137 on the commutator shafts and also with the electromagnet 165 which steps the brushes 166 .. 171 round. The digit commutators, Figs. 2, 6, 7. Each one carries three sets 113 of three conducting discs, i.e. nine in all, each disc showing the product of the appropriate digit and one of the digits 1 .. 9, e.g. the middle set of three discs 118, 119, 120 on the "6 " commutator show 24, 30, 36, by two, three and three gaps respectively for the " tens " on one half of their periphery and four, nil, and six gaps for the units on the other half. The three discs in a set are connected together and brushes e.g. 127, 129, 133 run on them individually while a brush 134 is always in contact. The shaft 153, Fig. 2, is continuously driven so that the -discs 147 are always rotating and will drive the resiliently mounted discs 145 whenever a solenoid 146 is energized and so drive the appropriate commutator. The control discs 135, 136, 137 have twenty-one positions in some of which they are inactive. Their " active " positions are shown by small letters over the brushes in Fig. 1, e.g. disc 135 is inactive in positions 10, 20 (except for the " unit " commutator which is special). The registering means comprise step-bystep mechanism energized by solenoids. Multiplication action. The numbers are set up and the start key " 209 " depressed. Circuit is made through brush 170 of 109, conductors 212, 213, units column of 102, 214, contacts 215, 216 of control disc 135 through solenoid 146 to battery 218 and ground. Commutator " 6 " is thus rotated and as key 8 in multiplicand units column is depressed, the brush 233 becomes active and, in the half revolution initiated, makes and breaks eight times the circuit of the units solenoid 186 of the registering device which accordingly through pawl and ratchet means steps the indicator forward 8 units. Similar action takes place for the other digits in the multiplicand but for simplicity the units figure only is dealt with. Rotation brings the commutator to point 10 on disc 135 and there is a stop ; but a circuit is now completed through adding key 239, brush 242, control disc 136-whose brush 243 closes contact at position 10- conductors 244, 245 to brush 171 for electromagnet 165 which, being energized, steps arms 166 .. 171 forward from terminals 1 on to terminals 2 in their banks and opens its own circuit in 171. Circuit now goes from 171, though conductors 247, 248 to control disc 137 (which also has a brush 249 active in the " 10 " position) from brush 250 to the "6 digit " solenoid 146 so that the " 6 digit " shaft starts rotating again and moves from position " 10 " to position " 11 " when discs 136, 137 go dead but disc 135 becomes active to allow the solenoid 146 to be re-energized and drive the shaft through another half-revolution to position " 20." During this movement the circuit to the " tens " solenoid 186 of the device 110 is made and broken four times and so forty is indicated. Position " 20 " being reached, the discs 136, 137 are active again and a circuit is completed through disc 136 as before (except that it is now through its " 20 " brush) for the electromagnet 165 which now advances the brushes 166 .. 171 of the distributor 109 to terminals " 3." As before a circuit is made from brush 171 through control disc 137 for solenoid 146 which steps the six-commutator round one step to " 21 " rendering all its control discs inactive. Digit " 6 " having finished its work, the next digit in the multiplier is brought in (in this case the digit 1). No. 3 terminal of 170 completes circuit through 264 to the " tens " column of the multiplier bank of 102 and then as before to the appropriate digit commutator solenoid 146 action of which then repeated leaves the brushes 166 .. 171 on terminals " 5." Action when digit " 0 " occurs in multiplier. No key being depressed in the hundreds column of the multiplier, circuit from the " 5 " terminal of 170 goes through conductor 282 up and down the " hundreds" bank and back through conductor 240 to electromagnet 165 which is therefore energized to step the brushes 166 .. 171 to position 6. But terminals " 5 " and " 6 " in 170 are connected, so 165 is re-energized to step them all to position " 7 " when circuit is completed through the thousands digits key (two) for normal action. At the completion of this the full product is shown on the register 110. The brushes are now on terminals " 9 " and the solenoid 165 being energized steps them round to " 10 " which on 171 is connected to " 9 ", 165 is re-energized to step them to " 1 " when circuit is discontinued. Meanwhile through contact " 9 " of 170 the solenoid 104 has been energized which releases all depressed keys and returns the banks 101 and 102 to normal. Adding. For this operation, adding key 239 is depressed which cuts out the advancing electro magnet 165. A number then being set up on the multiplicand bank 101, the starting key 209 is depressed and circuit is made through the left-hand contact of 239 and contact 211 of starting key for the solenoid 146 of the unit commutator so that this does a half turn and the number set up is indicated on the register. But in position "10" a circuit is now completed for the resetting electro - magnet 104 through the control disc 138 which is peculiar to the " unit commutator and is " active " in positions " 10 " and " 11." The banks are reset and starting key 209 opened so that the commutator solenoid circuit is also opened but through the lower contact 300 of disc 138. The solenoid 146 is reenergized and moves the commutator to position 11 and so power is now available through disc 137 to take it on to "20," this half revolution not affecting the register, as there are no " tens " in multiples of unity.