Patent GB-191030391-A (GB)
Title: Improvements in Calculating Machines.
Inventor: BARRETT GLENN JENNINGS
IPC: G06C7/06
Filed: 1910-12-31
Granted: 1911-12-14
Abstract: 30,391. Barrett, G. J. Jan. 3, [Convention date]. Adding-apparatus.-A key-set crank - operated multiple-bank machine is fitted with improved key latching and releasing means, easing- springs and overthrowpreventing means for the actuating-racks for the totalizer, and with means for governing the speed of operation. Keyboards; keyboard interlocks; differential mechanism. - The keys have slots to engage a grate 201 shortly after the machine is started, and have a latching- notch 200<c> and bevel 200<b> and a deeper releasing - bevel above. These engage, between fixed plates, sliding plates 202 held forward by springs 503, against which rest spring-controlled latches 210 which engage and hold pins on the counter - operating racks 204. These are formed of parallel bars in pairs having the keyengaging s t o p s 204<c>, 204d alternately, which engage the right and left turned tongues 200<d> on the ends of the key stems, and which are undercut to retain the keys depressed. Key release is effected during operation by a bail 383 on a shaft 359 striking pins 216 on the keylatching p l a t e s 202. This bail can also be rocked to release the keys by a special key 355, Fig. 3, through lever 356 and link 385, or by a special lever 393, Fig. 22, mounted on the hub of the main lever and having a tongue 394<a> to rock a shaft 358 and thereby depress a slide 343, which also engages the lever 356. A repeat key 380, on depression, throws out of action an arm 376 carrying a pin 374, which normally engages a pawl 373 on a main rocking- segment 372, by the toggle action of which the lever 381 and key-release bail 383 is usually operated. Governing speed of operation; full-stroke mechanism.-The main shaft 357 is fast to a rocking-plate 313 having teeth 313<a> to engage a full-stroke pawl 329 and having a sliding rocking segment 317 connected by a spring 507 to a plate 317 engaged by the main lever, so that if the lever is jerked forward a shoulder 317<a> on the latter segment engages a holding-pawl 316 until the segment 313 overtakes it and throws out the pawl. A dash-pot 300 is also connected to segment 313 and a main spring 508 is attached to the segment 317. A stud 349 on the segment 313 engages a slotted lever 354 linked to a yoke 350, which, by means of links 353, normally holds the upper locking grates 201 for the keys out of action. A lower cross-bar 325 of the yoke carries forward arms 208 shouldered to bear against the key racks 204, so that all then take up their places, at the same time rotating rack segments 107 idly till, on the return stroke, pawls 110 pivoted to them are thrown into engagement with the counter-actuating pinions 102 bv curved arms 337. These arms 337 are mounted on a frame 326, 328 the end of which has a finger 363, Fig. 3, connected by a spring 522 with a lever which is rocked by a cam note thereon engaging a roll on a lever 368, which has pins 369 engaged by a tongued pawl 387 on the rocking segment 372 on the main shaft. This yoke frame 328 also raises detent pawls 113 from engagement with the pinions 102 while throwing the pawls 110 into gear. To prevent actuation if keys are not properly depressed, an arm 391 blocks the movement of the main segment 313 unless the key-locking grating 201 is properly home. Transfer mechanism.-Transfer is effected by springs 501 tensioned between the shouldered links 208 and the key racks 204, the racks being slotted to allow the extra step at transfer. Normally, the racks are arrested by arms 121 attached to the segments 107, which always engage the racks, meeting stops 115, but these are tripped for transfer by arms 115<b> thereon engaging transfer teeth 106, the stops 115 being held back if necessary by latches 118, which are however released by the arms 121. Zeroizing-mechanism.-To zeroize the numeral wheels, the key-release lever 393 on the hub of the main lever is brought up to the lever, thus freeing all the key racks; the lever then being operated as usual, full travel is permitted to all the racks up to nine units, except the units denomination which moves ten; the return movement then moves all the counter wheels in the positive direction to zero. The counter wheels are arrested at their proper points by stops 129 for the backward movement.