Patent GB-310370-A (GB)
Abstract: 310,370. Friden, C. M. F. April 24, 1928, [Convention date]. Multiplying and dividing apparatus.-A motor driven machine for the four rules comprises a totalizing-counter with reversible numeral wheels, actuators therefor having a uni-directional movement, and manual means for selecting the direction of rotation of the numeral wheels and for initiating the operation of the machine. As shown in Figs. 1, 2, and 3 a clutch is provided between the motor and the actuator shaft and the drive to the numeral wheels is through sets of normally inoperative transmission gears, the operation of the clutch and the selection of the gears being effected by the depression of either one of two control keys. The construction of the key-board, actuators, and totalizing-counter, the means for laterally shifting the totalizer carriage, and the zeroizing means are similar to those described in Specification 229,642. The driving shaft 14 connected to the motor drives the actuator shaft 5 through a clutch comprising a ratchet wheel 15 on the shaft 5 and a pawl 17 within a housing 16 secured to the shaft 14. The pawl 17 is normally held disengaged by a foot 18 thereon co-operating with a projection 22 on a spring controlled clutch lever 21. Movement of the lever 21 to control the rotation of the actuators 3 is effected by control keys 24, 25 either of which on being depressed is adapted, through pins 33, 37, to rock a lever 34 underlying a pin 38 on the clutch lever. The totalizer comprises numeral wheels 41 with pinions 44 arranged to be driven in one direction by a set of transmission gears 54 and in the other by a set of transmission gears 55, 56. The gears 54, 55, are normally in engagement with intermediate pinions 47 adapted to be driven by the actuators. The spindles of the transmission gears are carried in a frame 49 pivoted on the shaft 48 of the intermediate pinions and the frame 49 is provided with a projecting pin 64 engaging a slot in the end of an arm of a bell crank lever 62 the other arm of which is connected by a link 66 to a lever 65. The position of the lever is controlled by pins 67, 68 on the stems of the keys 24, 25 which pins on depression of the corresponding key raise or lower the rear end of the link to select the set of transmission gears. This selection is effected prior to the release of the clutch by the lost motion existing between the lever 34 and pin 38. The frame is held in its adjusted position by a pin 74 on the lever 65 co-operating with one or other of the notches 72, 73 in an extension 71 of the clutch lever 21. Return of the lever 65 to its neutral central position is effected by a double cam lever 76 engaging a pin 77 on the lever. Transfer mechanism.-Transfer in either direction of rotation is effected by a single set of transfer pins 8 spirally arranged on the actuators. The transfer levers are composed of two parts one 83 mounted in the totalizer carriage and the other 85 pivoted to the frame 49. A pin 46 on a numeral wheel, at transfer, depresses the levers 83, 85 and places the cam part 9 into the path of the appropriate pin 8 to deflect it into engagement with the next higher pinion 47. The levers are restored to normal position by cams 12 on the actuators. Spring pressed balls 82, 87 are provided to hold the levers 83, 85 in either position of adjustment.