Patent GB-158180-A (GB)
Title: Improvements in and relating to differential mechanism for calculating apparatus controlled by punched record sheets or the like
Filed: 1919-10-27
Abstract: 158,180. Haddan, A. J. H., (National Cash Register Co.). Oct. 27, 1919. Statistical machines with several totalizers; selecting denomination.-Relates to machines controlled by punched record-sheets and comprises differential mechanism consisting of a totalizer, an actuator movable differentially in one direction and then back to normal, and an electromagnet energized once during every operation of the actuator by means controlled by the recordsheet. The main shaft 96 of the machine is driven through bevel-gearing 94, 95 from a shaft 53 driven through worm gearing from a motor 49. Five rows of totalizers 103 are arranged in four rows of fourteen totalizers each, and a last row of thirteen, each row being mounted in an independent frame. Half the totalizers in each row are arranged on either side of the drive shaft 96. Two sets of differential racks 112 are provided for each row, one common to the seven on one side and one common to the seven on the other side. The racks 112 on opposite sides of the shaft 96 are connected together by racks 153 which gear with pinions 160 on four cross-shafts 161. Segments 170 are rocked clockwise and counterclockwise to an invariable extent each time the shaft 53 is given a complete rotation, the drive being by way of cam gear 173, 179 from a shaft 175 driven by spur gear 178, 177, 176 from the shaft 53. The segments 170 mesh with wheels 168 loose on the shafts 161, each shaft carrying a clutch 169, 181 by means of which the shaft is normally clutched .to the wheel 168. When the electromagnet 194 is energized, the armature 193 is withdrawn from an arm 192 of a bell-crank 188 thereupon rocked by a spring 196 to throw out the clutch 169, 181 which is then locked by teeth 183, 199. The rack 112 is connected to the rack 153 through a transfer lever 154 pivoted on pins 155 carried by the rack 112, and carrying pins 157 which pass through vertical slots in the racks 112 and inverted L-shaped slots in the rack 153, while the pins 155 pass through horizontal slots in the rack 153. The movement given to the shaft 161 is one step more than the digit to be entered, this step being idle as regards the racks 112; relative movement takes place between the racks to the extent of the slots 159, 156. After the racks 112 have been differentially positioned, and before their return stroke, the totalizers selected as described in Specification 158,084 are moved into gear with the racks 112 and operated on the return stroke of the racks, the totalizers being disengaged after the racks are returned to normal. The clutches 169, 181 are so formed that they engage when the member 169 is reversed to return the parts to normal position. The rear row of totalizers comprise thirteen in number, the six to the right comprising three grand totalizers and three cashiers' totalizers. These are operated by separate but similar mechanism. Each denomination of an " amount " is represented in the perforated record by five index positions, and two positions are punched to represent a digit. These co-operate with the pin box described in Specification 158,084- and with a commutator to energize the appropriate magnet 194 to arrest the movement of the rack bar 112 when it has moved an amount corresponding to the digit. The commutator is made up of five discs 371 each disc having lugs and slots, and two end discs 375 so arranged that the discs can be assembled together as shown in Figs. 7, 8. A set of five brushes 382 connected to contacts for the pin box bear on the discs 371 and two brushes 382 connected to a battery through magnets 194 bear on the end discs 375. By the completion of a circuit through two of the discs 371 and the corresponding contact pins, the appropriate electromagnet 194 is energized whenever the commutator has moved one more step than the number of steps corresponding to the digit represented by two perforations through two of the index positions of the corresponding denomination.