Patent GB-606629-A (GB)
Abstract: 606,629. Calculating-apparatus. ALLENWALES ADDING MACHINE CORPORATION. May 23, 1946, No. 15660. Convention date, Feb. 13, 1943. [Class 106 (i)] A calculating-machine comprises a totalizer, a keyboard having keys for entering amounts into the totalizer, said keyboard being bodily shiftable between two positions, and means co-operating with the keys and the totalizer for effecting, in one position of the keyboard, additive entry into the totalizer of the amount set up on the keys and, in the other position of the keyboard, entry into the totalizer of the complement of the amount set up on the keys, so as to subtract that amount from the amount in the totalizer. Keyboard. The keyboard, Fig. 17, is mounted for lateral movement at the rear on a rod 25 and at the front on studs 50b and may be removed by urging a spring finger 52 forwardly to disengage a slot therein from a cross-member 51. The keyboard is normally maintained in a left-hand position by a spring 62, Fig. 13, but when moved to the right by means of a repeat lever 136, Fig. 7, when it is desired to subtract, the keyboard is retained in the righthand position by a latch 54. Each column of amount keys is associated with a plate 68 to latch each key in its depressed or undepressed position and a bail which removes a zero stop 69 when any key in the column is depressed. The latching plates 68 are rocked at the end of each cycle to release any depressed keys by a key-release bail 70 which is rocked by a lever 144 controlled by a stud 130 on a sector 17 secured to the main shaft 4. A stud 76 carried by an extension of the key-release bail engages the latch 54 when the key-release bail is rocked to allow the keyboard to return to the lefthand position if it has been displaced for subtraction. Depression of a correction key (not shown) rocks a lever 149 which in turn rocks the key-release bail and which has a hooked rear portion which engages an upward extension 154 of the lever 144 to prevent the rocking thereof. Moreover, a stud 155 on the lever 149 engages an arm 123 of a lever 118, Fig. 10, thus unlatching a plate 106 and the zeroizing lever 100, to which it is connected by a link 104, if the zeroizing lever has been operated. Repeat mechanism. With the repeat lever 136, Fig. 7, in the unoperated position, a stud 181 on the key-release lever 144 can enter a notch 138 in the repeat lever to enable a full movement of the lever 144. However, when the repeat lever is moved to the rear, full movement of the lever 144 is prevented by the engagement of the stud 181 with the lower surface of the repeat lever and neither the keyrelease bail 70 nor the keyboard latch 54 is rocked. Drive mechanism. A handle 5, Fig. 7, is detachably secured to the main shaft 4 which carries a sector 17 provided with notches 18 on its periphery which co-operate with a sprung pawl 19 to ensure a full stroke once the main shaft has been moved. The movement of the main shaft is limited by a sprung buffer 10 and controlled by a dashpot 163, Fig. 17. A motor-operated drive (not disclosed) may be employed. Differential mechanism. An operation of the main shaft 4 causes an arm 77, Fig. 17, and link 79 to move a cross-bar 31 forwardly and then rearwardly, thus releasing rack arms 32 which are urged forwardly by sprung stop-bars 36. In addition operations, the keyboard is maintained in its left-hand position in which any depressed key-stems co-operate with abutments on the stop-bars 36 to limit the movement of each stop-bar so that, during the return movement of the racks, the amount represented by the depressed keys is added into totalizer wheels 26. When the keyboard is in its righthand position for subtraction, any depressed key-stem in a column co-operates with abutments on a stop arm 41, which is pivoted to the stop-bar 36 and guided by a cam surface 43 to ensure proper co-operation with the key-stem, so that the movement of each stop-bar for denominations above the units denomination represents the nines complement of the number represented by the corresponding depressed key while, in the units denomination, the movement represents the tens complement of that number. If no key in a column is depressed, lugs 40a or 40, by engagement with a cross-bar 38, limit movement of the stop-bar in the units or higher denomination respectively to add into the corresponding totalizer wheel ten or nine respectively, the movement of the keyboard being such that the zero stops no longer block movement of the stop-bars. Transfer mechanism. Each rack 34, Fig. 9a, can move relatively to its rack arm 32 and is urged to the rear thereof by a spring 35 which is normally tensioned by the engagement of a lug 180 on the rack with a lug 177 on a transfer lever 168. However, when a transfer is to be effected, a cam 165 on the lower order totalizer wheel rocks the lever 168 to enable the lug 180 to pass over the lug 177 into abutment with a second lug 178, thus allowing the rack of the highar order to move one extra step. A latch 170 maintains the lever 168 in the tripped position and is rocked to restore the transfer mechanism by an arm 24 of the totalizer frame when the totalizer is disengaged during the next operation. Control of totalizer-engagement. Zeroizing. A depending arm 81, Fig. 10, of the totalizer frame 24 carries a stud 82 which is engaged in a cam slot of a lever 91 normally held by an arm 88 on the main shaft 4 in such a position as to maintain the totalizer pinions in engagement with the racks. In an addition or subtraction operation, the arm 88 releases the lever 91, which is sprung in a counter-clockwise direction, to disengage the totalizer during the first half-cycle, at the end of which an arm 99 carried by the main shaft engages a stud 90 on the lever 91 to restore the latter in a clockwise direction so as to re-engage the totalizer during the return movement of the racks. A shoulder 96, Fig. 7, on a latch 93 maintains the lever 91 in its restored position, but is raised at the end of the cycle by a stud 98 on the sector 17 to allow movement of the lever 91 at the commencement of the following cycle. The lever 91 is maintained in its extreme positions by a sprung detent lever 182. A rearward movement of the zeroizing lever 100 acts through a link 104 to rock a plate 106 and thereby to allow a counter-clockwise, Fig. 7, rocking of a lever 118 which is latched in the moved position by a nose on the plate 106. An arm 121 of the lever 118 is thus moved into a blocking position behind the stud 90 to prevent movement of the lever 91, which would disengage the totalizer, during the first half-cycle. At the beginning of the second half-cycle, the stud 130 on the sector 17 engages a sprung pawl 125 on the lever 118 to rock the latter in order to withdraw the arm 121 from blocking movement of the lever 91. Since the latch 93 is raised by a rearward extension 133, Fig. 10, of the link 104, the lever 91 is then released for movement by its spring to disengage the totalizer, the wheels of which will have been turned, during the forward movement of the racks, to zero, in which position the transfer cam 165, Fig. 9a, on each wheel abuts a lug on the forward end of the transfer lever 168. To permit the forward movement of the racks, the zero stops are rocked out of blocking position by a link 110, Fig. 10, operated by the plate 106 and connected to a lever 112 which engages the stud 76 in order to rock the key-release bail 70.