Patent GB-502958-A (GB)
Abstract: 502,958. Calculating - apparatus. CHICK, T. W. June 28, 1937, No. 18014. [Class 106 (i)] In a multiplying and dividing machine division is effected by setting up a standard series of multiples of the divisor, comparing these with the upper part of the dividend, selecting tho largest multiple that is less than the said part, registering the quotient figure corresponding to the selected multiple, subtracting this multiple from the dividend and setting the difference as the new dividend. The multiples are entered into separate totalizers negatively and the dividend is entered into these totalizers positively so as to obtain the differences. The multiple required is that in the totalizer containing the smallest positive difference and a selecting or canvassing mechanism is provided to isolate this'totalizer. The mechanism is also adapted to perform multiplication by setting up the standard series of multiples of the multiplicand, selecting the required multiple in accordance with the digits of the multiplier, and by summing the selected multiples to obtain the required product. Keyboard and differential mechanism. The machine as shown in Figs. 4 and 5 has banks of keys 1, the keys being numbered " 0 " to " 9 " and the " 0 " key serving-merely as a release key. Each key stem 3 is connected by a bridge piece 12, Fig. 7, to a second stem 11 and these stems carry teeth meshing with mutilated pinions 9 on a transverse shaft 10. A pinion of each pair of stems engages rack teeth on a plate 13. The plates 13 for each denominational order are supported on blocks 13b and each plate has a number of projections 14 for co-operation with the bridge piece to prevent depression of more than one key in any bank. When a key is depressed its plate is displaced and held by a latch 15. In the displaced position differential stops 19, 20 on the plate limit the travel of racks 21, 22 coupled to a pinion 24 on a transverse shaft 25 adapted to move downwardly a constant amount on the operation of the driving mechanism. The racks 21 are normally held inactive by a stop pawl 26 which is released by the plate 13 of any key other than the " 0 " key. The rack 21 in each denomination meshes with a gear 30 on a shaft 31 and receives a motion corresponding to the key depressed. Each gear 30 is formed with a sleeve on which is slidably keyed a gear 32. The gears 32 can be moved axially into alignment with positive or negative main differential actuating racks 34, 34a that are carried in mountings on arms 47 keyed to rock-shafts 48 operated at the proper time in a cycle to raise the racks to engage the gears 32. The racks 34, 34a are connected by interengaging pinions 35, 36 and pivoted toothed sectors 39, 40 so as to move to equal extents in opposite directions. The racks 34, 34a, can be restored by the operation of bails 500 engaging slots in the racks. Other bails 504 are provided for setting purposes in certain operations. Totalizer mechanism. The machine has four upper totalizer DP, DM, QM and QMT, for dividend or product, divisor or multiplicand, quotient or multiplier, and quotient summation register respectively. Each totalizer comprises a receiving wheel 50 which can be aligned with either the positive or negative actuating rack intermediate wheels 51, 52 and 53, Figs. 8 and 11, and numeral drums 54. Transfer mechanism. A transfer tooth 61b Fig. 10, on a wheel 61 in mesh with the wheel 51 co-operates with the part 69 of a double wheel 68 which at transfer displaces a lock bar 614 in the next higher denomination. The lock bar in its raised or lowered position, depending on the direction of rotation of the receiving wheel 50, places stop surfaces thereon in such a position as to free one or other of a pair of rocking members 55, 56. These rocking members are pivoted on transfer actuating bars 59, 60 which are displaced during the cycle of movement to cause a projection on the active rocking member to advance the transfer wheel 61 one step in the appropriate direction. After a transfer action the wheel 61 is moved axially to free the rocking members which are then restored to normal position, Fig. 9, and the wheel 61 restored to active position. To reset a totalizer to zero the transfer wheels 61 are slid to bring the tooth 61b thereon into the path of a projection 75 on arms 76 secured to the zeroizing shaft 77. Multiples-forming mechanism. To set up multiples of the divisor the receiving wheels 50 of the totalizer DM are engaged with the negative racks 34a and the totalizer zeroized to transmit their setting to the positive racks 34. At the same time pinions 94 are moved into engagement with the racks 34 and through larger pinions 93 transmit the movement to setting racks 92. These racks are arranged in pairs and formed with horizontal slots 97 in which a reading or sensing bar 98 may slide there being one bar 98 for each denomination. Each bar 98 engages a vertical slot 99 in'a pair of members 100 adapted to slide horizontally a constant amount by the actuation of a bail 101. During the travel of the bar 98 it encounters selected stop surfaces 102 on product plates 91, 91a, Figs. 4 and 13, with steps arranged in accordance with the units and tens of the partial products of the digits 1 to 10 by themselves ; the rearward movement of the plates is arrested by rear stop surfaces engaging a stop bar 103 secured to the setting racks 92. The product plates are formed-with units and tens product entering racks 103a, 104a, Figs. 4, 14 and 15, in -engagement with entering gear wheels 105, 113 of associated multiple totalizers 1x .... 9x and 10x. The entering wheels 105 are carried on clutch elements 107 which can be moved to engage a units gear wheel 109 which is connected through a clutch 111a to a wheel 112 meshing with the intermediate gear 52m of the totalizer. Similarly the entering gears 113 are connected through clutch elements 114 to a wheel 115 in mesh with a whee 1116 of the next higher denomination. The multiples can be entered positively or negatively depending on the timing of the operation of the clutches 107, 114; to enter the multiples negatively the clutches 107 are engaged during the outward movement and the clutches 114 during the return movement of the racks 103a, 104a. Restoring means for the product plates and racks is constituted by a pair of bails 191, 192. Lower racks and carriage mechanism. For transferring an amount from the dividend totalizer DP to all the multiple totalizers or for transferring an amount from a selected multiple totalizer to the dividend totalizer sets of lower differential racks 133. 133a are provided to co-operate with the receiving wheels 50m. of the multiple totalizers. The wheels 50m are normally out of alignment with the racks but can be moved to selectively engage one or other set when the racks are raised by the movement of arms 300, 300a on cross-shafts 305, 305a. The sets of racks are engaged by interengaging pinions 303, 304 so as to move equal extents in opposite directions. A pair of bails 600, 604, is provided for restoring these racks. The racks 133, 133a may be connected through a carriage mechanism to bottom racks 120, 120a which are connected by pin-and-slot devices to arms 118, 119, Fig. 5, integral with the sectors 39, 40, of the main differential racks 34, 34a. The carriage mechanism comprises upper and lower transverse shafts 124, 134, Figs. 4, 5, 18, 19, 22a and 22b, one for each section of the machine. Each upper shaft 134 has a gear wheel 135 which can be brought into operative alignment with rack teeth 136 on a depending portion of the rack 133 or with teeth 136a on a depending portion of the rack 133a. The wheels 135 are arranged in groups to move together in frames 125 each frame being formed with a rack 126 meshing with a pinion 127 on a shaft 128. The lower shafts 124 carry gear wheels 123 arranged in groups in frames 125a each frame having a rack 126a meshing with a pinion 127a on a shaft 128a. Each lower shaft 124 carries a wheel 129 aligned with a carriage rack 130 so that on raising the racks 130 the movement of the main differential racks may be transmitted through the racks 120 or 120a, and the shafts 124 to the carriage racks 130. The carriage racks 130 are formed with upper parts forming racks 131 to mesh.with gear wheels 132 splined on the upper shafts 134 so as to transmit the differential movement to the lower differential racks 133, or 133a and thence to the multiple totalizers. The wheels 132 are mounted in a slidable carriage 132a so that they can be aligned with any of the racks 131. The carriage 132a, Figs. 19, 20 and 22b runs on rails 238 and has a rack 236 at each end meshing with a pinion 234 on a shaft 235 driving by worm gearing from a shaft .230. On the shaft 230 is splined a gear wheel 800 which can be shifted by a column-shift selecting lever 801 into alignment with one or other of a pair of driving racks 804, 805. One or other rack can be moved to engage the wheel 800 by operating a rock shaft 810. The selecting lever 801 is connected at opposite ends to bell-cranks 820 and 828; the bellcrank 820 is controlled by a bar 827 movable to one side or the other of a central position by a manual control key ; the bell-crank 828 is connected to a column shift slide 209 operable during dividing and multiplying operations. Means are provided to lock the carriage against movement when not required. The movement and restoration of the carriage racks 131 is controlled by bails 1000, 1001. Operating mechanism and control means. The main shaft 705, Figs. 28a and 29a carries a plurality of complementary cams 703, 704, engaging corresponding follower arms 709a, 710a secured to a boss on a cross-shaft 712. An arm 709c integral with the follower arms has a roller 706 engaging a slot in a corresponding rack 702. The movement of the racks 702 can be transmitted to one or more of a plurality of driving shafts 700 by means of