Patent GB-493277-A (GB)
Title: Improvements in and relating to calculating machines
IPC: G06F7/46
Filed: 1937-02-04
Abstract: 493,277. Photo-electric multiplying - machines. BROIDO, D. Feb. 4, 1937, No. 3348. [Class 40 (iii)] [Also in Group XIX] In a multiplying-machine utilizing members representing partial products, one member is provided for each denomination of the multiplicand, and the members control a registering device by modifying beams of radiant energy coactingwith devices sensitive to radiant energy. The apparatus comprises an arrangement A for setting the multiplicand, an arrangement B for setting the multiplier, and an adding machine C which records the product. The part A contains nine cylindrical screens 3, one for each denomination of the multiplicand. Each screen is slotted to indicate all the products of any pair of digits as described in Specification 446,338, [Group XIX]. A key is provided for each denomination of the multiplicand which shifts axially one of the screens through one of the forked levers 21. The keys also operate numeral indicating wheels and printing wheels. Keys 38 are provided for the multiplier, each of which rotates all the screens 3 on their shafts 6 through apparatus shown in Fig. 4. In this, each key 38 operates indicating and printing wheels 42 and 44 and also moves an individual set of spirally arranged cams 45. A number of levers 50 one for each possible value of a digit are provided for each key. The appropriate one is released by a cam 45 and when one of the cams 57 is operated by a sector 70, the lever 50 is released. The sector 69 then rotates a drum 55 geared to the cylinders 3 and the drum is stopped at the appropriate point by one of the spirally arranged stop pins 61 striking the lever 50 which has moved. When the two factors have been set, shaft 71 is rotated. First the units cam 57 operates and the screens 3 are rotated to bring the partial products of the multiplicand by the units digit opposite a scanning cylinder 13 which contains a lens and a light sensitive cell and the products are transmitted to an adding machine C in a manner similar to that described in Specifications 446,338, and 475,943, [both in Group XIX]. The tens and hundreds and other cams 57 are then operated in succession and all the products are summed by mechanism C. This device comprises discs 92, Fig. 7, bearing racks and cams which each drive numeral wheels through clutches 82 controlled by the light sensitive cell. After one set of partial products has been read the set of discs 92 are moved one step to the left by operation of screw 106 in order to allow for the fact that the next set of products will be of denominations of 10 times the value. The results of mechanism C may be printed as well as indicated. In an alternative construction, screens 3 may be flat and the multiplicand is set by vertical movement thereof. The multiplier is then set by the movement of a mask horizontally in front of the screens and not by actual motion of the screens. The latter may also have the units and tens of the partial products arranged in separate rows with separate reading means for each. In a machine for non-decimal numerical amounts, such as British currency, one screen is provided for farthings, one for pence, one for shillings, and one screen for each denomination of the pounds amount. Several transmission arrangements of the kind described in connection with Fig. 1, transmit the partial products to shafts F, D, S, and L for farthings, pence, shillings and pounds respectively. Gearing transmits the values on shaft F to shaft D, the odd farthings being stored on a wheel IF. In a similar manner odd pence are stored on units and tens wheels ID and XD and odd shillings on wheels IS and XS. These wheels drive indicating wheels on shaft L which also carries a counter for the total of the pounds. If the multiplier is also of non-decimal character different sets of keys are provided for each denomination, each key operating through gearing with its ratio adjusted to convert all operations into amounts of the lowest denomination. This non-decimal apparatus can be considerably simplified by using a screen carrying a much greater number of partial products. The size of the screen then necessitates a screen of flexible ribbon wound on a reel. This ribbon is divided into areas X, one for each denomination of the multiplier, and each area is subdivided into areas Y for each numeral of the multiplier denomination, and these areas are subdivided into areas Z for each numeral of a multiplicand denomination. The partial products are indicated on these areas by slots as before. The screens are set according to the multiplicand by keys 23, Fig. 28, which turn the setting drum 208 to bring an area Z opposite to the scanning lamp 10 corresponding to the numeral of the multiplicand. The multiplier keys then operate the drum 208 through further mechanism to bring the desired area Z in the appropriate area Y before the lamp 10. The products are represented in the areas Z in terms of the final denominations.