Patent GB-270331-A (GB)
Abstract: 270,331. National Cash Register Co., (Assignees of Robertson, W. H.). May 1, 1926, [Convention date]. Cash registers; adding- apparatus.-In an adding- mechanism the engagement of the totalizer with the actuating-mechanism takes place at the same time in the cycle for sub-total and total-taking purposes as for adding. The invention is described as employed in connection with the ledger number keyboard of a cash register such as is described in Specification 176,781. The ledger number keys and their cooperating differential and totalizing mechanisms are mounted in a detachable frame disposed on the right of the machine, the shaft 34, Figs. 12 and 13, for operating these mechanisms being coaxial with the main shaft 30 of the cash register and normally clutched thereto by a pawl 32 carried by shaft 30 and engaging a notch in a disc 33 fixed to shaft 34. In the home position the pawl can rise out of the notch by reason of a recess 56 in a fixed retaining ring 40 but this movement is not possible until the machine release shaft 57, Fig. 1, has been liberated. Thus, provided this release has been effected the shaft 34 may be rotated by a hand crank independently of the cash register to effect additions &c. as described below. Differential-mechanism. - The ledger number keys 70 control, through a one-way pawl 112, Figs. 1 and 2, the time of disengagement of a latch 111 wih a driving segment 140 rocked by cams 145 on the shaft 34. The latch is carried by a differential arm 110 connected by a link 114 with the printing-mechanism and adapted in adding-operations to position an actuating segment 160 by means of a loose arm 162 and a link 161. The arms 110, 162 are connected by a coiled spring 164 but in clockwise movements the arm 110 may positively drive the arm 162 through a pin 163. The return of the driving segment 140 carries back the arm 110 by the engagement of a pin 170 with the surface 171 of the arm and disconnectible means are provided normally to couple the arm 110 with the arm 162 in order that the actuator 160 shall be positively returned to zero to enter the amount in the totalizer. This means consists of a pawl 148 pivoted on the arm 110 and adapted normally to engage a notch 173 in the arm 162 a fixed arcuate rail 181 preventing disengagement throughout the out and home strokes of the differential arm. A zero stop 90 is operated by a bell-crank 91 connected with a key detent plate and may also be rendered ineffective in total-making operations by means described below. The totalizer is carried by arms 188 pivoted at 90 and drawn downwards to engage the totalizer with the actuators at the commencement of the cycle, in order to receive the amount entered in the previous operation. The downward movement is effected by a pawl 192, Fig. 10, contacting with a flattened pin 187 and mounted at the end of an arm loosely pivoted at 190, a pin 194 on the arm engaging a cam slot in a bell-crank lever 195 rocked by a cam 205. This cam is shaped so that at the beginning of the cycle the totalizer is lowered into engagement with the actuators. At the end of the homeward stroke of the differential mechanism, disengagement occurs and subsequently the totalizer rocks still further away from the actuators and engages the transfer sectors 216. Transfer-mechanism. - The transfer-effecting sector 216, Figs. 6 and 7, is controlled by an arm 219 urged to the right by a spring 226 but normally restrained by a latch arm 228 connected rigidly to an arm 227 lying in the path of a transfer tooth 189 belonging to the next lower numeral element. At transfer therefore the latch arm is displaced to free the sector but this is held from completing its stroke by a bail 222 until the sectors are engaged by the totalizer whereupon the cam 250 rocks the bail to the right to liberate any tripped sectors so that they may effect transfer. Printing totals and subtotals.-The machine is conditioned for adding or total-taking by a lever 284, Fig. 14, capable of three positions as shown. When it is moved to the right it cams a broad pinion 281 into engagement with loose and fast gears 277, 279 so that the rotation of the main shaft 34 is conveyed in a 2 : 1 ratio to the shaft 278. Aliners 272, 273 are provided for the pinion 281 and gear 279 respectively to ensure correct meshing. During the first cycle of rotation of the main shaft a cam 285 fixed to shaft 278 rocks a shaft 292 and so through arms 98 and pins 97, Fig. 1, withdraws all zero stops 90 to permit the differential arms after their return to home position to travel throughout their full range, the latch 111 being then disconnected at the 9 point by pin 306. When the arms first return to home position the pawl 148, Fig. 2, normally coupling the arms 110, 162, is disabled by being rocked clockwise by an arm 302 connected at 300 with the arms 98, the arm 162 and actuator 160 being thus enabled subsequently to move independently of the differential arm 110. At the beginning of the second cycle the totalizer engages the actuators, as usual, but now the actuators, being uncoupled from the arms 110, are controlled by the totalizer pinions until these have advanced to 9 as determined by the transfer teeth 189 meeting the arms 227 rendered unyielding as explained belaw: The actuators are then locked by pawls 341 rocked by the cam 330, Fig. 5, through the medium of an arm 345. Rigid with this arm is another arm 336 adapted to move beneath the transfer arm 227 to hold this fast for stopping the transfer tooth 189 in the 9 position. The actuators 160 and the arms 162 are therefore held in positions corresponding with the number standing on the totalizer while the differential arms 110 are returned to home position by the driving segments 140. Later in the second cycle the segments and arms move upwardly again and the latches are now disconnected by pawls 317 carried by the arms 110 and controlled by pawls 315 pivoted on the arms 162. The pawls 317 have forward arms underlying pins 328 on the latches and when in the clockwise movement of the arms 110 the downwardly-extending arms 316 of the pawls 317 meet the pawls 315, the forward arms raise the latches and thus break the connections with the driving segments to position the type wheels in accordance with the amount on the totalizer. At the end of the operation it is necessary to add unity to the totalizer to bring the numeral wheels to zero and for this purpose the units wheel is furnished with a sector 216 and arm 219 similar to those used for transferring, the arm being normally latched by a lever 350, Fig. 5, tripped in total or sub-total taking by engagement by the arm 336. If the operation is a total-taking one, the totalizer must not engage the actuators in the next adding operation and therefore the pawl 192, Fig. 14, must be rocked away from the pin 187. To effect this an arm 355 pivoted to the control lever 284 and guided bv the pin 356 has a shoulder 358 to take over the nose of the pawl so that when the control lever is returned to the " add " position the pawl is withdrawn from engagement with the pin 187. To prevent key manipulation when the control lever is out of the " add " position a pin 362 is adapted to rock an arm 365 into obstructive position with reference to the detent plate 94. A notched arm 370 fast on the release shaft 57 also seizes the pin 362 to prevent movement of the lever after the machine has been freed for operation.