Patent GB-665882-A (GB)
Abstract: 665,882. Calculating apparatus. AKTIEBOLAGET FACIT. June 7, 1948 [July 3, 1947], No. 15345/48. Class 106 (i). A calculating-machine comprises a setting toothed wheel for each denomination which drives a numeral wheel and cooperates with nine toothed cylinders corresponding to the digits 1-9, gear transmissions arranged between a manually or motor-driven shaft and the toothed cylinders for driving the latter at different speeds, and means under control of item-setting members to cause each setting toothed wheel to roll on the teeth of the toothed cylinders, when the latter are at rest, into mesh with the toothed cylinder corresponding to the setting of the associated setting member. A number is set on the machine by means of a slidable differential setting-member 99, Fig. 2, in each denomination. On operation of the machine, a bent end 99a of each setting-member is engaged by teeth 89c on a rack-bar 89 slidable on a shaft 91 which is raised to effect this engagement and guided by slots in plates 73, 90. A bar 101 is then moved forwardly to restore the setting-members 99 and to impart a differential movement to the rack-bars 89, the racks of which mesh with gears 66, Fig. 1, fast to segments 65 carrying planet-wheels 68 in mesh with driving-wheels 15. During this movement, a shaft 83 is rocked counter-clockwise and arms 84 lift a shaft 85 passing through holes therein and carrying arms 87 to which is secured a locking bar 88 which is thus disengaged from teeth in the segments 65. When the segments 65 are rotated by the rack-bars 89, each planet-wheel 68 is caused to roll from engagement with a fixed plate 72 over a series of toothed cylinders 74-82 into mesh with that one corresponding with the number set in that denomination. Transmission wheels 12 are then lowered into mesh with the driving-wheels 15 and, to ensure proper engagement, the latter are simultaneously rocked through a small angle by rocking the segments 65 carrying the planetwheels 68. This is achieved by rocking the shaft 85, which is formed at its ends with eccentric pins 85a mounted'in vertical slots 86a, and so moving the locking-bar 88 forwardly. Each toothed cylinder is then rotated through a number of steps depending upon the number with which it corresponds, to rotate its planetwheel 68, driving-wheel 15, transmission wheel 12 and numeral wheel (not shown) differentially. In order to enter numbers by the " short-cut " method, the cylinders 74-78 are rotated by gearing (not shown) through one to five steps respectively in the additive direction during each machine cycle and the cylinders 79-82 are rotated through four steps to one step, respectively in the subtractive direction. When the number entered in a denomination exceeds five, one is subtracted from the next higher denomination as follows. Each rack-bar 89 has a cam-slot engaged by a pin in an arm 94 pivoted to an arm 92 having a tooth which, when the rack-bars 89 are lowered after being differentially set, engages in teeth 89a of the rack-bar of the next higher denomination. A locking bar 105 which engages slots in the arms 92 while the rack-bars are raised is now slid forwardly to release the arms 92 and a member 98 is rotated. Surfaces arranged on the rotor 98 then engage the arms 94 in turn, starting with that of the lowest denomination, so that, where a rack-bar has moved through more than five steps and the arm 94 has been lowered by the cam-slot, it is now raised and forced against a rod 106, to rock the arm 92 so as to withdraw the next higher rack-bar through one step. The driving-wheels 15, segments 65 and associated parts of the different denominations are separated by guide-plates 64 secured to a tube 69 slidable on a shaft 70, the end-plates 64, the carrying plate 73 and the whole unit together with the rack-bars 89 and the associated parts forming a carriage laterally movable on the shafts 70 and 91 for carrying out multiplication. The rack-bars 89 are zeroized by means not described at the end of the complete operation.. Specifications 551,311 and 661,874 are referred to.