Patent GB-804771-A (GB)
Title: Multiplying Machines
Filed: 1955-02-14
Abstract: 804,771. Calculating-apparatus. F.A.I. FABBRICA ADDIZIONATRICE ITALIANA S.p.A. Feb. 14, 1955 [Feb. 20, 1954; Aug. 13, 1954], No. 4344/55. Class 106 (1). A machine for performing multiplication by the repeated addition of a multiplicand with appropriate denominational shifts has a set of rack bars settable to represent the digits of a multiplier for the purpose of controlling the multiplication operation. The bars are mounted in a frame which is rockable to engage them with toothed sectors connected to the main differential mechanism of the machine so that they may be set by the latter. The invention is applied to a motor-driven ten-key machine not described in detail but having a pin-carriage 220 controlling differential actuating segments 218 for a totalizer 217 and printing mechanism. Setting the multiplier.-The multiplier is entered in the pin-carriage 220 by operation of the number keys and then a key 256, Fig. 11, is depressed. The key 256 rocks a lever 260 to engage the motor and rocks a lever 262 which causes the mainshaft 234 to rock a lever 261 counterclockwise. The lever 261 rocks a halfround shaft 25 and, through resilient connections, shafts 8 and 91, the latter through a lostmotion arrangement. The shaft 25, Fig. 5, disengages detents 22 from the multiplier racks 7; the shaft 8 moves a transverse bar 11 to the right to restore all the racks 7; and then the shaft 91 operates through cams 92 engaging pins 30 in a frame 4, in which the racks are slidably mounted, to tilt the frame about pivots 3 so as to engage the restored racks 7 with sectors 152. The latter are coupled by links 154 to the differential segments 218, Fig. 1a, which at this time have been moved to differential positions in accordance with the entered multiplier. The shaft 91 also acts through a link 210 and lever 211 to depress a link 2131 which causes the totalizer to be non-added during the current cycle. The bar 11 is then returned to the left and in the latter part of the cycle, the segments 218 are restored so that the sectors 152 set the racks 7 to represent the multiplier. Short-cut multiplication.-The multiplicand is entered into the pin-carriage and then a key 236, Fig. 12, is depressed. The key is held by a latch 237 which maintains the motor in operation, and causes a lever 247 to be rocked by the mainshaft 234 during each cycle to operate the mechanism by which the multiplier racks 7 in turn are restored step by step. This mechanism is carried by a plate 156, Fig. 5, secured to a carriage movable transversely of the machine along a shaft 87, and arranged initially for cooperation with the lowest-order multiplier rack 7. This carriage is locked to the pin-carriage by operation of the key 236. The mechanism includes a counting tooth 167 which is raised into engagement with teeth on the operative rack 7 during part of each cycle by the rocking of a half-round shaft 89 connected by a link 276 with the lever 247. The latter also acts through a link 248 and an arm 112 to shift a member 116 to the right to free an arm 106 for rocking movement and to shift an actuator 110 normally (for multiplier digits 1-5) arranged to engage a pin 107 of the arm 106. An extension 109 of this arm engages a plate 57 extending across the machine and supported for movement forwards and backwards. The plate 57 is embraced by a slide 165 carrying the tooth 167. Thus, the tooth 167 is moved by the lever 247 so as to restore the operative rack 7 by one step during each cycle of the machine. When the rack 7 is fully restored, a feeler 162 can enter a notch 176 in an extension 174 of the rack. The feeler 162 is engaged by a bail 64 which is urged counterclockwise during each cycle, to cause the feeler to sense the extension 174, by a link 197, Fig. 1a, actuated through a spring by the mainshaft. When the feeler enters the notch, a bail 67 is able to rock and also a bail 85 coupled thereto. The bail 85 causes a step shift of the pin-carriage and also of the carriage carrying the plate 156 supporting the restoring mechanism for the racks 7. If a multiplier digit is greater than 5, a feeler 169 is rocked by engagement with a portion of the corresponding rack 7 when the counting tooth 167 is moved into engagement with that rack. The feeler 169, Fig. 3, rocks a plate 52 fast on a shaft 50 carrying an arm 51 which trips a latch 45 to release a slide 42 which rocks a lever 33. The shaft 50 is arranged to rock arms 191, 193, Figs. 7a and 12, which raise the actuator 110 so that the arm 106 will be rocked in the reverse direction and will cause the counting tooth 167 to step the rack 7 to the left instead of back to the right. The arm 191 also depresses a link 196 which sets the machine for subtraction instead of addition. After a number of cycles equal to the complement of the multiplier digit, the feeler 162 can enter a second notch 177 in the extension 174, and so cause a step shift to the next denomination. During the last step of the rack 7, a side extension 171 thereof rocks a pendant 19 associated with the rack 7 of next higher order. The pendants 19 are carried by a shaft 18 raised by the rocking of the lever 33, Fig. 3, to engage offset portions of the levers 19 with teeth of corresponding racks 7. Thus, the next rack 7 is advanced one step to correct for the complementary number of repeated subtraction operations. If a multiplier rack 7 is in zero position or has been fully advanced, the feeler 162 will at once enter either the notch 176 or the notch 177 so as to cause an immediate step shift. The bail 64, Fig. 1a, in moving the feeler 162 also actuates a link 225 which causes a mainshaft-operated lever 227 to depress the non-add link 213. Eliminating two lowermost multiplier digits.- A lever 223, Fig. 1a, may be operated to shift the carriage 155 carrying the rack-restoring mechanism two places to the left prior to the multiplication operation. Concluding operation.-Following depression of the multiplication key 236, a bail 62, Fig. 5, is urged downwardly but it is blocked by the extensions 174 of the racks 7 until each of them has been restored to the position shown or fully advanced to position a notch 175 beneath the bail 62. Then the bail 62 rocks and acts through a link 198<SP>1</SP>, Fig. 12, to rock the latch 237 which releases the key 236. An arm 251 released by the key, frees a locking arm to permit the pincarriage and the carriage carrying the rackrestoring mechanism to return to their rest positions. The bail 62, Fig. 6, also acts through a lever 150 and link 148 to rock an arm 144 and so release a lever 140 which is then shifted by a stud 138 driven by the mainshaft 234. A supporting lever 135 is thus rocked and frees a lever 132 which drives a member 129 leftwards. This member has two laterally offset prongs and moves under the control of a cam 130<SP>1</SP> so that either one prong engages a stud 127 to rock a plate 121 or the other similarly rocks a second plate behind the plate 121. The plates are respectively connected by links 200, 201 to the total and sub-total keys so that either a total or sub-total operation follows in which the product is printed.