Patent GB-466118-A (GB)
Title: Improvements in or relating to cash registers and similar accounting machines
IPC: G06C7/10
Filed: 1935-11-20
Abstract: 466,118. Cash registers. NATIONAL CASH REGISTER CO. Nov. 20, 1935, No. 32129. Convention date, Nov. 20, 1934. [Class 106 (i)] In a cash register or similar accounting machine having printing and indicating means that remain in differentially set position at the end of the machine operation, zero printing and eliminating is controlled in each denomination by a member (e.g. the latch carrier) of the differential mechanism that returns to home position during each operation. Differential mechanism.- The differential mechanism for eachamount bank includes a differential arm 13, Figs. 1 and 3, and a latch 14 pivoted on a stud 20 of a carrier 21. The arm and carrier are both rotatable about the axis of a shaft 16 and are connected by a spring 22 that tends to hold the carrier in abutment with a stud 23 on the arm. A driver 12 co-operating with the latch is rigid with a sleeve 15 and receives constant clockwise and counterclockwise excursions at each machine operation. By the abutment of the latch with a surface 19 of the driver, the latch and differential arm are constrained to follow the clockwise movement of the driver until the arm is arrested by contact with a zero stop pawl 26 or the stem 11 of a depressed key. The latch is now rocked one step in excess of the movement of the differential arm, wherein, by the engagement of its stud 24 with a slot 25 in the arm, the latch is rocked counterclockwise out of engagement with the driver and into engagement with one of a series of registering notches 30, where it is held by an arcuate surface 32 of the driver. To prevent premature disengagement of the latch, due to the spring 22 being overcome by the inertia of the differential arm and connected parts, the pin 24 of the latch engages a slot 27 in a disc 28 freely rotatable about the axis of shaft 16, the slot being so shaped that the inertia of the disc tends to hold the latch in engagement with the driver and thus offsets the inertia of the differential arm. The totalizer actuators are driven by the differential arms 13 through toothed sectors 35 and gears 37, but the indicators and type wheels are driven by the latch carrier 21. Minimum-movement device. The indicator drum 143, Fig. 1, and type-wheel 140 of a denomination are interconnected by a sector 138 driven from the associated latch carrier 21 through a minimum-movement device comprising a beam 38 and arcuate link 39, Figs. 1, 3 and 6, At the conclusion of the setting movements of the differential members, the links 39 are rocked by rollers 49 counterclockwise about their pivots 41 until their inner edges abut sleeves on the shaft 16, in which position the setting of the indicators and type-wheels will correspond with that of the latch carriers 21. Controlling printing of zeros. First embodiment. As shown in Fig. 1, the asterisk on each type wheel is situated in zero position and the zero one step in advance of the asterisk. Thus the asterisk will normally be in printing position when the differential arm 13 is arrested by the zero stop pawl and the latch carrier makes one step of movement, while to print a zero, the type-wheel must be retracted one step from this position. For this purpose, the pivot 41 of the arcuate link 39 of the minimum-movement device is not mounted directly on the latch carrier 21, but is carried by a bell crank 42, Fig. 6, pivoted at 43 to the carrier, means being, provided to rock the bell crank counterclockwise when a zero is to be printed. These means comprise a roller 44 mounted on the bell crank and embraced by a cam slot 45 in a plate 46 that is rockable about the axis of shaft 16 and operatively connected by a link 58 to a lever 59, 80 pivoted on a shaft 61 rocked with the rollers 49 about the shaft 52 at each operation. A roller 79 on the arm 80 of the lever is adapted to co-operate with a blocking arm 78 of locking lever 72 having a second arm 76 co-operating with the cam-shaped edge 82 of the latch carrier 21, Fig. 3. If the latch is broken in the zero position, the latch carrier moves one step, the locking lever 72 remains in normal position, the lever 59, 80 rocks idly clockwise about its shaft 61 as the latter rocks counterclockwise about shaft 52, the cam plate 46 is held in normal position by a spring 67 and an asterisk is printed. If the latch is broken by the stem of a depressed key, the locking lever is rocked to interpose its blocking arm 78 in the path of stud 79 and the lever 59, 80 is rendered effective to rock the cam plate 46 clockwise. This movement of the cam plate is ineffective to shift the link 39, since the stud 44 has moved clockwise with the latch carrier away from the operative part of the cam slot. However, by means of overlapping lugs 81 on the levers 59, 80, all the levers 59, 80 of lower denomination will be rendered effective to rock their associated cam discs 46, with the result that if the latch of one of these lower denominations is broken in zero position, the associated cam slot 45 will become effective to rock the link 39 and position the zero for printing. Controlling printing of zeros. Second embodiment. If the zero is situated in usual position on the type wheel with the asterisk one step in advance of it, the locking lever 72, Fig. 9, is arranged to present its arm 84 to stud 85 of lever 86 (corresponding to lever 59, 80, Fig. 6) when the latch is broken in zero position. Locking levers of denominations in which keys are depressed are rocked counterclockwise to ineffective position by the cam edge 82. Locking levers of lower denomination than that in which a key is depressed are also disabled by overlapping lugs 87.