Patent GB-540311-A (GB)
Abstract: 540,311. Calculating- apparatus. BALL, W., KEEN, G. P., and BRITISH ADDING & CALCULATING MACHINES, Ltd. April 29, 1939, No. 7756/40. Divided out of 540,283. [Class 106 (i)] In a machine having a number of totalizers with the pinions arranged in denominational sets a totalizer selecting mechanism is provided comprising a set of control members, one for each denominational set of pinions, adapted to be adjusted to permit engagement of the selected totalizer pinions with corresponding operating members associated with the differential actuating mechanism and means for establishing and interrupting the drive between the selected totalizer pinions and the actuating mechanism during a machine cycle. The invention is shown applied to machines as described in Specifications 263,505, 288,672, [both in Class 106 (i)], 343,448, 343,473, 343,474, 343,475, 343,476 and 352,958. The keyboard and differential mechanism is similar to that described in Specifications 540,283 and 540,315. Totalizer selecting mechanism.-Nine totalizers are provided with the pinions 11 of a denomination arranged around a corresponding actuating wheel 44, Figs. 2 and 3, rotatably mounted on a shaft 45. The wheels 44 are connected to the differential actuating racks 12 through intermediate pinions 46 axially movable into alignment at appropriate times in the cycle of operation for adding, subtracting and total-taking operations. Each pinion 11 is secured to a sleeve 52 on a spindle 53 which extends through a corresponding radial slot in a partition plate 10. Each spindle 53 is provided with a collar 57 bearing against a single notched disc 55 secured to the shaft 45. A circumferential spring 58 on each side of the plate 10 encircles the spindles 53. The selective setting of the discs may cause the totalizer wheels to engage the actuating wheel 44 directly the other totalizer wheels being locked out of engagement by the disc. In the form shown the engaging movement is indirect. For this purpose the ends of the spindles 53 pass through heart-shaped slots 62 on a control disc 59 mounted for limited oscillatory movement on the plate 10 and provided with an arm 66 having a pin engaging an arm 303 of a control shaft 309 operated at appropriate times in the cycle. A bank of totalizer selection keys co-operate with a differentially movable rack similar to rack 12, which through gearing rotates the shaft 45 to align the notch of the cam disc 55 with the totalizer to be selected so that when the control disc 59 is displaced the spindle 53 is moved down from the left-hand side of the heart shaped slot into the lower notch 64 while the other spindles are held in the notches 65. Transfer mechanism.-Each totalizer pinion carries a single tooth disc 67 which, at transfer, engages the corresponding arm 70 of a spider member 69 rotatably mounted on the shaft 45. When the member 69 is rocked its arm 71 rocks a bell-crank 206 in one direction for addition and in the opposite direction for subtraction so as to move a pin 209 thereon from the position shown in Fig. 2 to a position opposite the branches 211 or 212 of a zig-zag slot in the normally stationary rack 14 of the next higher denomination. This allows the rack to move an additional step to effect the transfer towards the end of the cycle of operation after the release of the holding latches at opposite ends of the rack. The bell-crank 206 is retained in one or other of its set positions by a latching lever 76 and is released by the pin 84 on the control lever 66 engaging the end 85 of the latching lever. Total-taking mechanism. - In total-taking operations the transfer parts act as stops for the zero position and the spider member 69 is held against movement by its connection with a lever 90 having a forked end engaged by a rectangular shaft 93 when the latter is rotated to a position at right angles to that shown in Fig. 2. Movement of the racks 12 during total taking operations is controlled in the known manner by pawls engaging ratchet teeth on the differential rack mechanism. Printing mechanism.-Printing is effected in a manner similar to that described in Specifications 343,448 and 540,320.