Patent GB-1086340-A (GB)
Abstract: 1,086,340. Calculating machines. WALTHERBUROMASCHINEN G.m.b.H. Aug. 5, 1965 [Aug. 7, 1964], No. 33629/65. Heading G4B. A calculating machine for multiplication by the " short cut " method comprises a plurality of counting mechanisms 69, 70 between which the additions or subtractions of the multiplicand in respect of each multiplier digit are distributed and means for adding together the amounts accumulated in the counting mechanisms to form the required product. In operation the digits of the multiplier are set up by keys in pin carriage 26, Fig. 3, which moves into alignment with racks 35 in known manner. The multiplier key (20, Fig. 1, not shown) is then operated to initiate a first machine cycle. During the first half revolution the racks 35 move until arrested by pins 27<SP>1</SP> and rotate the type segments which print out the multiplier on paper tape (see below). At the end of this first half revolution sliders 30, Fig. 2, are coupled to the racks 35 via levers 200 and intermediate sliders 197, such that when the racks return to their initial positions the sliders 30 are set to the value of the multiplier digits. The multiplicand is next set up in pin carriage 26 and the multiplicand key (21, Fig. 1, not shown) depressed to start a series of machine operations. During the first half of the multiplying operation the racks 35 again travel until arrested by pins 27<SP>1</SP> and rotate the type segments which print out the multiplicand (see below). Depression of multiplicand key 21 also causes rod 328, Fig. 9, to be released, pin 338 thereon moving to position 338<SP>1</SP>. During movement of bar 231 to the left at the beginning of the machine revolution, coupling rod 328 is entrained, deflecting lever 285 anticlockwise, thus lifting pawls 321, 323 out of engagement with ratchet teeth 318 and releasing sequence control lever 313 for clockwise deflection by an amount determined by the step depth detected by a main finger 260, Fig. 17. At the same time rod 282 is lowered and releases the fingers mounted in the slider carriage 235 in a given sequence. Slider Carriage and Finger Mechanism.-The shift finger 255, Fig. 17, is maintained by a pin (268, Fig. 7, not shown) in the raised position so that main finger 260 will not be shifted to the left together with the counter selector finger 270 and descend to the step representing e.g. 6 on the units slider 30, Fig. 2. This level is two steps down and consequently control lever 313 moves clockwise by two units. Thus with the carriage 235 in the units position only two machine operations will ensue. Sensing edge 273 of the selector finger 270 bears down on the step associated with numeral 7 and the upper surface of its extension 269 remains flush with edge 277 so that sensing edge (311, Fig. 8, not shown) can ride over extension 269. A swing arm (127, Fig. 11, not shown) is therefore deflected to bring counters 69, 70, Fig. 3, ready for engagement. The subtraction finger 256, Fig. 17, can drop because the slider 30 in question is set to 6 and thus mechanism (not shown) prepares counters 69, 70 for subtraction. Two machine revolutions are therefore performed at the slider 30, the multiplicand being transferred to each of the two counters 69, 70. A final machine revolution follows automatically in which, during the first half, the accumulated total is cleared from counter 69 by racks 35 and, during the second half, transferred to counter 70. The sum contained in counter 70 is then printed. Printing mechanism.-As illustrated in Fig. 3, depression of a key will cause bar 42 to swing to the right which allows racks 35 to yield to springs 39 and their rack teeth 53 will rotate type quadrants 57 via intermediate wheel 54. An aligning rail 76 which together with shaft 77 and two arms 78 forms a tiltable frame is then lowered into engagement with the wheels 54 and assures alignment of the selected type with the printing line on the paper roll 81. The type quadrants 57 are rotatably mounted on levers 83 affixed to a shaft 82. These levers 83 are retained against the pull of tension springs 84 by a restoring bar 85. Tens transfer.-As illustrated in Fig. 3, if during addition or subtraction the counting wheels 71, 72 pass from 9 to 0 or 0 to 9, the tens transfer teeth 104 push back carry-over teeth 105 which form part of carry-over levers 106 which normally lock tens transfer levers 67 in position. The bottom ends of the levers 67 co-operate with angled stops 66 on supplementary racks 63, 64 of the next higher order such that said racks cannot yield to the pull of springs 65. When counting wheels 71, 72 pass from 9 to 0 or 0 to 9 then lever 67 is released and the next higher rack 63, 64 can be shifted by spring 65 one division to the left.