Patent GB-890585-A (GB)
IPC: G06C23/02
Abstract: 890,585. Calculating-machines. CONTINA BUREAUX - UND RECHENMASCHINENFABRIK A.G. March 10, 1959 [April 8, 1958; April 22, 1958], No. 8263/59. Class 106 (1). A calculating machine having a steppedtoothed drum with transfer and totalizing elements arranged in a circle round it and having at one end a crank handle for its operation is now provided at the other end with a motor drive. The invention is applied to a machine similar to that described in Specifications 656,185 and 656,601. Driving mechanism. Addition and subtraction.-In the arrangement shown in Figs. 1 and 2, the drive unit is incorporated in the machine which is sufficiently compact to be held in the hand. The motor 23 drives the drum shaft 33 through gearing 25, 26, 28, 30 and a spring 31 which allows the shaft to be driven independently of the motor by the crank handle (not shown). The motor is energized by an accumulator 24 which may be charged from a main supply through a socket 42 and charging device 41. A control slide 1 is moved downwardly for addition and upwardly for subtraction. In the latter case, a ball 4 cams an arm 5 carried by the slide into engagement with a projection 8 of the drum 9 and the latter is raised to render a complementary set of toothings effective. In either case, an extension 11 of the slide 1 cams a lever 14 counterclockwise (Fig. 2) to engage contacts 34, 35 in the motor circuit and to remove a roller 37 from a notch 40 in a disc 42 keyed to the drum shaft 33. Moreover, an arm 17 releases a brake spring 19 from a brake disc 20 on the motor shaft. The drum 9 will thus be driven by the motor until the slide 1 is restored, after which it is driven until the roller 37 re-enters the notch 40, whereupon the motor circuit is de-energized and the brake 19 applied. If the machine is to be operated manually, a slide 342 is moved to place an insulating plate 341 between the contacts 34, 35. In a second embodiment, Fig. 3, the drive unit is arranged to be fitted to an existing machine. A pin 69 in the drum shaft of the machine is engaged by resilient forked members 65 of the drive unit. The drum is moved between the addition and subtraction positions by an arm 72 carried by the control slide 43 and acting through springs 59, 60 on a lever 61. In a third embodiment, Fig. 10, the drive unit is intended to be stood on a desk and receives the calculating machine itself on its upper surface. In this case, the drum is moved between the addition and subtraction positions by keys 78, 79 respectively pivoted about shafts 82, 83 in the base unit and acting through springs 85, 108. Depression of either key rocks a member 87 which withdraws the stop roller and closes the motor circuit contacts. In yet another embodiment, Figs. 14 and 15, the control slide a is formed with a rack b which rotates, through a pinion d, a wheel e having a long tooth which engages a notch in the drive shaft i so as to shift it (and the drum shaft) axially for addition and subtraction. Setting multiplier digit.-In the last embodiment, Figs. 14 and 15, a disc may be set in accordance with the multiplier digit which is indicated by a drum o engaged by a ball detent r. As the drum e is moved from its zero position, a projection t moves from a latch u which is thus allowed to engage one of two slots x in the control slide a to retain it in the operated position so that the machine repeatedly cycles. In each cycle, a pin y in a wheel z on the driving shaft engages teeth n of the disc l to restore it one step per cycle. After the set number of cycles, the projection t withdraws the latch u to allow the control slide a to return to its normal position.