Patent GB-335213-A (GB)
Abstract: 335,213. Mathys, A. W., (Monroe Calculating Machine Co.). June 19, 1929. Adding and subtracting apparatus for monetary and other non-decimal values; differential mechanism.-A calculating-machine has a number of selector devices representing decimal equivalents of banks of non-decimal value keys, the number of such devices and their associated banks of keys corresponding to the maximum number of decimal places registered, certain of the keys setting up an amount on one selector device, while other keys set up an amount on a plurality of such devices. Certain of the banks are so arranged that when a key of one bank has set up a decimal equivalent on a selector device, operation of a key in a second bank adds to such setting a second decimal equivalent, including a setting on the selector device set up by the first key. Fig. 1 shows the keyboard arranged for calculations according to the British monetary system. The first four left-hand denominations are used for pounds, the next two for shillings, and the last four for pence and farthings. Shillings, pence, and farthings are entered in the numeral wheels as a decimal value (to the sixth place) of a pound. Each selector device comprises two rocking bails 19 each connected to one part of a compound pinion 5. The bails are set by the engagement of the cam ends 26 of the keys with offset parts 33, 34 of the bails. The offsets on the left-hand bails effect, when engaged by the keys, a setting of " 5 " on the pinions, the right-hand offsets causing settings of from " 1 " to " 4." The keys, Fig. 4, of the shillings and pence denominations have cam extensions to control more than one pair of bails. In the 6th denomination from the right, one key only, marked. " 10s " is used, its depression causing the rocking of the corresponding left-hand bail to set " .5 " on the related pinion. The righthand bail of the same pair, effecting a setting of from " .1 " to " .4 " on the same (10s) pinion is controlled by the keys of the preceding. denomination (units of shillings). These keys also control the left-hand (" .05 ") bail of their own denomination. The right-hand (" .01 " to " .04") bail of the units of shillings' denomination is utilized, together with the bails of the four preceding pence denominations, in setting up pence amounts. For example, in setting up 8s. 11¢d., depression of the 8s. key rocks the right-hand bail of the tens of shillings denominations to set up " .4," and depression of the 11¢d. key rocks the right-hand bail of the units of shillings denomination, together with the proper bails of the four pence denominations, to set up- " .047917 " as shown in Fig. 5. Each denomination of keys has a locking bail 6 which engages notches 8, 9, in the keystem when the key is in its raised or depressed position respectively. Depression of a key rocks the denominational locking bail to release any other depressed key of the same denomination. The locking bails 6 of the four pence denominations are interconnected by a bar 37 so that the depression of a key in any one of the said denominations will release any other key therein already depressed. A clear key 15 is provided which operates by effecting. the depression of all the. " 0 " keys simultaneously. If the clear key is held in depressed position while certain values are set in the keyboard, and is then released, all the " 0 " keys will remain depressed. If other keys in other denominations are then set, the corresponding " 0 " keys will be released. If the clear key is then operated,'these other keys will be released in the usual way, but those first set (with the clear key held depressed) will remain depressed. The usual non-repeat mechanism clears the entire keyboard. In a modification, the machine is adapted for calculations in feet, inches and fractions of an. inch. Specifications 27231/12 and 216,174 are referred to.