Patent GB-128965-A (GB)
Title: Improvements in Adding Machines.
Inventor: DEHN FRANK BERNHARD
IPC: G06C7/06
Filed: 1917-07-12
Abstract: 128,965. Dehn, F. B., (Automatic Bookkeeping Register Co.). July 12, 1917. Adding-apparatus.-Relates to adding-machines of the kind in which spring-retracted, differential, rack-bearing members are released on the forward movement of the operating-shaft to take up a position determined by the depressed item keys when arms on the shaft are removed from projections on the differential actuating-members, such arms serving to return these parts to their original positions on the return stroke of the operating-shaft. In the invention, the differential members are provided with stops for a second set of differential parts consisting of stepped curved arms which are yieldingly connected to the operating-shaft and serve to position the typebearing members. The keyboard is of the flexible variety, and the apparatus is provided with repeat and total keys the second of which serves as an error key if depressed without movement of the operating-shaft. Means are provided for changing the colour ribbon on depression of the total key, and also for locking the differential actuating-members in the set position on taking a total, such means also serving as a brake on their return movement. The banks of item keys 33 are carried between horizontal flanges 27, 28, Fig. 8, formed on separate key-post frames 19, and the keys are locked in the lowered position by spring-retracted curved plates 38 which are pivoted between lugs 41, Fig. 5, on the frames 19 and engage shoulders 46 when the keys are depressed. With operating-means. - The differentiallymoving actuating-members consist of spring-retracted sheet-metal plates 50 bearing projections moving in slots 63, 64, Fig. 5, in the frames 19 and provided with a series of notches forming vertical stops 52 adapted to engage shoulders 34 on the keys. Normally, the differential members 50 are held against the influence of their springs by arms 79, Fig. 2, which engage rollers 81 thereon and are carried by the main shaft 11. At the first part of the movement of the main shaft, the differential members 50 are freed from the retaining-arms 79 and move forward to the positions determined by the depressed keys or to the zero position, which movement is permitted to the parts 50 of the banks wherein no key is depressed by projections 69, Fig. 8, on the locking-wings engaging slots 68, Fig. 5, in the members 50. With printing-mechanism.-Setting of the typecarriages 99, Fig. 2, sliding on type-levers 85 carried by a shaft 86, is effected through a stepped cam 153 on the operating-shaft 11, into engagement with which a bell-crank lever 145, secured to a shaft 112, is forced by a spring 151. Connected to the shaft 112 by projections 114 engaging a longitudinal groove 113 in the shaft is a series of arms 111 formed with notched stop-pieces 120 adapted to co-operate with stops 123 carried by sliding plates 124 connected to the differential members 50. Links 105 serve to communicate movement of the arms 111 to the type-carriers 99. The first step of the cam 153 causes a link 143 connected to the lever 145 to move a transverse rod 109 carried by a frame 144 away from the type-levers 85. Continued movement of the cam causes the engagement of the stepped stops 121 with the differentially-set stops 123, and the consequent upward movement of type-carriages releases latches 94 from the type-levers 85, each latch being provided with a lug 102 lying over the latch to the left, so that upward movement of any latch raises those to the right. The final step of the cam causes the link 143 to force the frame arms 144 against a third catch 91 to release projections 90 on the type-levers and allow ears 163 on spring-pressed plungers 155 to perform the printing operation. On the return of the crank, all parts are restored to their original positions. The record-sheet is fed by the rotation of the platen 174 by a pawl 191 carried by a lever 187 rocked by projections 188, 188<1> on a shift-bar 189. Totalizing-counters. - The shaft 247 of the totalizing-counter is carried by pivoted arms 247a, Fig. 2, and raised and lowered into engagement with racks 260 on the differential members 50 by cam-slots 257, Fig. 9, formed in arms 248 secured to a shaft 249. In the disengaged position, the counter-pinions are locked by teeth 263 on the key-post frames 19. Movement of the arms 248 is effected by the shift-bar 189 operated by a crank 241 from the main shaft and slotted at 266 to engage a pin 267 on a spring-retracted arm 265 secured to the shaft 249, the counterpinions being lowered into engagement with the previously-set racks at the end of the movement of the operating-shaft. The arms 248 are held in the set position by the engagement of a spring- retracted latch 302 with a pin 304 on the arm 265. At the completion of the return movement of the shift-bar 189, the catch is lowered by a stud 307 thereon, and the counter is returned to the normal position. Disengagement of the depressed keys is effected, on the addition of an item, by a rail 310 pivoted on the shift-bar 189 at 307 and connected therewith by a pin-and-slot connexion, a spring 314 serving to retain it in the raised position. Formed on the upper surface of the rail is a cam-member 318 shaped as shown in Fig. 10. In front of and above the cam 318, and running across the machine, is a bar 321 having pins 322 adapted to engage the lower free edges of the curved key-locking plates 38 and rock them to release the keys, when the bar is moved on the return of the shift-bar 189, by the engagement of a pin 323 with the lateral inclined edge of the cam 318. On the forward movement of the shift-bar, the pin 323 travels along the curved face of the cam and depresses the rail 310. Printing totals; error keys.-The total key 342 is provided with two inclined faces 344, 348, Fig. 10, adapted to engage respectively a pin 345 on the bar 321 to free any depressed keys, and a pin 349 on the total slide bar 335, which moves in fixed brackets 189<1> and lowers the counterwheels through a slot 338 engaging the pin 267 prior to the forward movement of the differential members 50 on the operation of the main handle. A shelf 362 on the shift-bar 189 locks the total key in the depressed position by engagement with a pin 362<1> thereon. When the operating-handle is moved to the forward position, the differential members move forward until stopped by engagement of pins on the transfer pinions with the racks 260. Distinguishing colours.-Depression of the total key rocks a shaft 233 through a lever 239 and an arm 235 on the shaft thus raising an arm 231 controlling the position of the multicolour printing-ribbon. Too rapid movement of the members 50 during the return is prevented by pawls 368, Fig. 2, mounted on a shaft 238 and rocked by engagement of tongues 369 thereon with a groove 367 in the shaft when the shaft is rotated by a projection 377 on the shift-bar 189 engaging an arm 375 on the shaft. The pawls, during totalizing, serve by engagement with teeth 371 to lock the differential members in position and, on their return, act as brakes, being raised out of engagement by a second projection striking the arm 375. Repeating-devices.-The repeat-key 325, Figs. 9 and 10, 'is provided with a pin 332 which, on depression, strikes an inclined edge 311 and lowers the bar 310 to remove the cam 318 from the engaged position and renders it non-effective with regard to the rod 321. Depression of the key must be effected, before the return movement of the shaft 11 commences and may be released after the shaft has reached the normal position.