Patent GB-608033-A (GB)
Abstract: 608,033. Calculating-apparatus. FORD, G. E. July 9, 1943, Nos. 11191/43 and 15166/44. [Class 106 (i)] A multiplying machine has means for setting up representations of the logarithms of the multiplicand and multiplier after these have been entered into the machine, means for adding to the logarithmic multiplicand the logarithms of the multiplier digits one by one, each in a respective multiplying cycle to produce the logarithms of the partial products, means for obtaining the antilogarithms of these products and means for accumulating the said antilogarithms to give the final product. In the machine described, the multiplicand may be in sterling and the multiplier a whole number and a decimal or fraction. The factors are read from a punched card and the final product is punched on the same card. The cards are sensed by pins, the movements of which are transmitted through a connection box 44, Figs. 1B, 3, to raise groups of stops 46, 47, 48, 49, in a basket 45, Fig. 3, the groups representing respectively the multiplicand divided by 960, the multiplicand proper, the whole-number part of the multiplier, and the fractional part of the multiplier multiplied by 960 as described in Specification 516,553. In the subsequent multiplication, the multiplicand proper is first multiplied by the whole-number part of the multiplier and then the multiplicand /960 is multiplied by the fractional multiplier X 960. Storing the factors. The whole multiplier stops 48 and the fractional multiplier stops 49 are read by bars 92, 93, moved to the left, Fig. 3, by springs to contact the stops when a common restoring bail 95 is moved by cams and levers (not shown in Fig. 3). A shaft 124, carrying multiplier and fractional - multiplier storage wheels 121, 122 is raised and lowered by cams to engage these wheels with the bars and thus to receive from the bars the multiplier and fractional-multiplier settings. The connections in the box 44 which divide by 960 the multiplicand read from the card are such that stops 46, relating to the same denomination of the amount "multiplicand /960 " may be raised in four columns simultaneously. The values relating to each denomination are added and entered into the corresponding denomination of multiplicand /960 storage wheels 185. Each of four related columns of stops 46 is read by a respective bar, e.g. 90G, 90H, 90I, 90J, Fig. 6. A pair of intermediate wheels 120 is mounted on the shaft 124 moved into upper, intermediate and lower positions in the former and latter of which the wheels mesh with racks on the bars 90G, 90J and 90H, 90I respectively. If either wheel 120 passes through zero transfer to the corresponding wheel 120 of the next higher denomination is effected by a cam 155 which rocks a latch 156 to allow the next higher rack teeth 152N to move one step relative to the rack on which they are mounted. The amounts standing on each pair of intermediate wheels 120 are entered on to a corresponding single wheel of the storage wheels 185, Fig. 3, one intermediate wheel 120 of the pair being returned to zero by a vertical rack 180, 186 when a restoring bar 189 is moved down, the rack being also engaged with the storage wheel 185. A second rack 181, 187 also descends at the same time and in mesh with the other intermediate wheel 120. The racks 180, 186 and 181, 187 are then shifted by rods 183 to disengage the lower rack parts 180, 181 from both intermediate wheels 120, to disengage the upper rack part 186 from the storage wheel 185 and to engage the other upper rack part 187 with that wheel so that, when the racks are returned upwards by the restoring bar 189 the amount from the other intermediate wheel 120 is added into the storage wheel 185, these latter wheels then holding the " multiplicand /960 ". The whole multiplicand is transmitted to a storer 232 by multiplicand racks 229 and pinions 228 engaging teeth on bars 91 which take settings from the multiplicand stops 47. Obtaining and adding logarithms of factors. When the factors. have been stored the stop basket 45 is cleared and the reading bars 91 ... 93 again released to the action of their springs. The whole and then the fractional multiplier reading bars are allowed to move seriatim to control multiplication by each digit of these two amounts in turn. The multiplier reading bars are at this time engaged with the multiplier storage wheels 121, 122. The seriatim release is controlled by an escapement bar 251, Fig. 12, urged to the left by a spring and having a gap 271 which comes opposite each bar 92, 93 in turn. When each bar 92, 93 is taking the initial setting from the stop basket 45, it swings a corresponding lever 261 into the path of a pair of arms 285, 286 on the escapement bar 251. During multiplication, this bar is rocked (by means not shown in Fig. 12) so that the arms 285, 286 escape past each set lever 261 in turn the escape bar 251 thus moving step-by-step to the left. As soon as the reading bars 91 ... 93 are released to the action of their springs, the whole multiplicand bars 91 take up the whole multiplicand setting from the multiplicand storer 232. The multiplicand /960 bars 90 remain at zero since the intermediate storage wheels 120 in mesh with these bars have been zeroized during the transmission of the multiplicand /960 to the appropriate storer 185. The whole-multiplicand bars 91, Fig. 3, have lugs 355 moving beneath the lower ends of stops 322 in a logarithmic stop basket 310 which can slide horizontally in a frame 313, Figs. 1A, 1B, reciprocated vertically by a rotary cam. When the frame 313 moves downwardly the lugs 355 on the whole-multiplicand bars 91 push up stops 322. The bottom ends of the stops 322 are spaced equally but the top ends are spaced to the right from a datum line according to the logarithms of the values of the stop. The logarithmic basket 310 is then moved to the left a distance corresponding to the logarithms of the operative multiplier digit, the total distance of each protruded stop 322 from the right then being equal to logarithm of the corresponding multiplicand digit plus the logarithm of the operative multiplier digit. This longitudinal movement of the logarithmic stop basket is controlled by a bar 372, Fig. 3, moved by a spring until arrested by a latch 373 on the operative multiplier bar 92; the motion being transmitted by links 371, Figs. 1A, 1B, to position a pin 382 which allows a plate 367 to descend until arrested by the engagement of one of a series of equal steps 383 with the pin 382. A lever 362 connected to the logarithmic stop basket then swings anti-clockwise until a lug 388 at its upper end meets one of a set of logarithmicallyspaced steps 387 in the plate 367. Obtaining anti-logarithms of partial products. The logarithmic stop basket 310, Fig. 3, is then reciprocated upwardly whereby the set stops 322 engage the lower ends of stop wires 391 in a translator 390, these wires being arranged inside the translator in such a way that their upper ends 392 are spaced from a datum line a distance proportion to the antilogarithms of the. spacings of the lower ends 391. The wires are also branched to allow for transfers, e.g., if a logarithmic basket stop 322 representing 63 pence (from the partial product 9d. X 7) is active to push on the lower end 391 of a translator stop wire, the upper protruded end 392 of the translator wire will be at a position corresponding to 3d. and a branch in the shillings denomination corresponding to 5s. will also be protruded. The translator stop wires 392 are read by partial-product reading bars 405. To reduce the length of the stop wire connections inside the translator 390, the wires are repeated in groups several times in each denomination and the partial-product reading bars 405 are provided with a corresponding number of reading lugs. Most of the partial-product accumulator wheels 420 receive entries from two columns of translator stop wires, e.g. in the case of the partial-product 6/3 X 6, the units of shillings wheel receives 6/- from 6/- X 6 and 1/- from 3d. X 6. Each of these columns of stops has a separate reading bar 405, one bar having a rack passing under the wheel 420 and the other having an upstanding rack 432 over the wheel, the wheels being engaged with the lower and upper reading bars in turn as .the bars move out and back again. The units of pounds accumulator wheel 420 has to receive entries from three columns of translator stop wires (e.g. in the case of the partial-product ú1 19s. Od. X 9). One of the two reading bars engaging' this wheel is made in two parts slidable relatively to each other by 0 ..-. 4 steps, this sliding being controlled by latches released by the translator stop wires raised to represent the pounds parts of products derived from the units of shillings denomination. When multiplication by all the digits of the whole-number part of the multiplier is completed, the escapement bar 251, Fig. 12, jumps to the left to release the first reading bar 93 for the fractional part of the multiplier. During this movement, a cam (not shown) on the escapement bar 251 causes the clutching of a cam to a rotary camshaft. The latter cam then moves the multiplicand racks 229, Fig. 3, into mesh with the multiplicand /960 storage wheels 185. Multiplicand racks 229 then descend and multiplicand reading bars 91 are thus set to represent the multiplicand /960, the value subsequently being set on the logarithmic stop basket 310, which is later moved as described above in accordance with the logarithm of the first digit of the fractional part of the multiplier. Varying the denominational value of the partial products. When the logarithmic stop basket 310, Fig. 3, descends to take the multiplicand setting from lugs 355 on the multiplicand bars 91, another lug 462 on each bar engages a corresponding rear stop 461 in a rear part of the logarithmic stop basket having a horizontal sliding