Patent GB-147265-A (GB)
Abstract: 147,265. Mays, J. F. April 10, 1919. Adding - apparatus; transfer-mechanism.-Transfer mechanism of the escapement type for multiple-bank, key-set, key-operated calculating - machines is provided with controlling-means common to all the keys and operated by the depression of any one of them to delay the completion of the transfer until the return movement of the keys has been completed. Operation of the transfercontrolling means is effected by the initial part of the down-stroke of the keys which is allowed by lost-motion devices between the differential actuating- shafts and the driving-members of the numeral drums. Differential movement is imparted by the keys to spring-controlled shafts 31 bearing sectors 43 engaging with pinions 44, Figs. 10 and 11, connected to disks 232 driving the numeral drums 38 through pawls 233 and internal ratchet teeth 231. Connexion between the pinions 44 and the disks is made through lost-motion devices comprising pins 251 on the disks engaging slots 252 in the pinions, springs 249, connecting the pins 251 to pins 250 on the pinions, serving to return the disks 232 to their initial positions determined by stops 253, 254. The transfer mechanism is of the escapement type, and movement is conveyed from the lower drum shafts 39 through sleeves 340, Fig. 5, and continuous reducing-gearing 341, 342 to wheels 361 loose on sleeves 369, carried by the framing, through which the drum shafts 39 pass freely. Connexion between the wheels 361 and escapementwheels 360 is effected by spiral springs 364, Figs. 5 and 8, secured to pins 359, 362 on the wheels. The pins pass through slots 365, 363 in floating wheels 356, of the kind described in Specification 16941/15, provided with lateral teeth adapted to be engaged by spring- controlled pawls 351 carried by spring-retracted bell-crank levers 350, 350<a>, Fig. 6, pivoted at 354. Oppositely-directed snail cams 346, 347, adapted to rock the levers 350, 350<a>, are driven by pinions 343 on the sleeves 340, the cams being so arranged that, at the transfer point, the levers are rocked to allow the floating wheels to be drawn forward through one step by previously-tensioned springs 357 connecting pins 358 thereon with the pins 359. Movement of the wheels 360 is transmitted to the shafts 39 of the higher indicating drums through pawls 366 thereon engaging internal ratchet teeth 367 on wheels 368 secured to the shafts, this connexion allowing direct setting of the drums by the keys. Prevention, during key operation, of movement of the wheels 360 consequent on a transfer is effected by pawls 375, pivoted at 374, which are rocked into position to engage the teeth of the wheel 360 by the movement of a slide 59 which occurs on the initial idle part of the downstroke of any key, such movement being allowed by the lost-motion connexion 251, 252. Mounted on the key differential shafts 31 are cams 76 adapted during this idle movement to rock a link 71 connected by a toothed sector 68, a pinion 65, a crank-pin 65<a> and a link 64 to the slide 59. The crank pin is moved from the position shown in Fig. 6 through ninety degrees to the left to a dead centre with the shaft, 66, thus preventing any pull from the spring-drawn wheels 360 being transmitted to the keys, the key stroke being consequently lightened. Pins 302 on the slide 59 serve to rock the pawls 375 into and out of locking position by engagement with slotted arms 373 carried by the pawls. In operation, at the transfer point. the springs 364 are fully tensioned. the wheels 360 being locked by the pawls 375. Under the tension of the springs 357 the floating wheels 356 are, when released by the pawls 351, drawn forward through a single step of movement from the left-hand position shown in Fig. 9 to the central one. On the completion of the return movement of the keys, the wheels 360 are released and drawn forward by the springs 364 into the position shown on the right of Fig. 9, the slots 365 serving to limit the movements of the pins 359. During these last movements the springs 357 are tensioned for the next operation. Overthrow of the wheels 368 and thus of the indicating drums at transfer is prevented by pawls 377 pivoted to the pawls 375 and normally held in the position shown in dotted lines in Fig. 6 by springs 379. When the pawls 375 are rocked to release the wheels 360 the pawls 377 are brought into position to be struck by the teeth of the wheels 368 and to be moved to the position shown in full lines against stops 380 from which they are removed by the next locking movement of the pawls 375.