Patent GB-1048619-A (GB)
Abstract: 1,048,619. Calculating machines. K. DIEHL. Aug. 14, 1964 [Aug. 16, 1963], No. 33146/64. Heading G4B. A four-rules ten-key calculating- machine has means for setting the decimal point before a calculation and adjusting the position of the output so that the decimal point is still in the correct position. The decimal point is adjusted by use of a knob 15 actuating a slide 181. This slide has teeth 182 and rotates a pinion 147 to position a shaft 137 according to the number of figures after the decimal point. The shaft has a number of abutment pins spaced helically, the axial distance between them being equal to the distance between denominations in the register. An arm 175 engages with teeth on a pinion 138 to lock the shaft in its adjusted position so that a dog 69 on the register carriage 30 strikes one of the pins 144. The shaft has limited axial movement and this is such that the carriage 30 is correctly aligned when held by the dog 69 engaging a pin 144 whether it is moving to the left or to the right. There is also a certain amount of angular play between the teeth 182 and the pinion 147 and the shaft may also be held by a latch 148 engaging the pinion 147. In this case the dog 69 can pass between adjacent pins 144 and the carriage will complete its full travel. In the position shown in Fig. 7 the machine is set for normal calculations in which the decimal point is ignored and the carriage 30 is free to move unimpeded by the pins 144 at any time. If the slide 181 is moved one place to the left, the machine is set for division operations in which the largest possible quotient is produced, and the dog 69 then abuts a pin 167 (Fig. 6, not shown), mounted on and parallel to the shaft 137. Division.-To effect a division operation, the dividend is set up on a pin box in the usual way and the division key (:) is depressed, thus transferring the dividend into the main counter mounted on the carriage 30. If the slide 181 is in the position for whole number division the carriage 30 is held at the left-hand end of its travel by a latch 315. If it is set for division with largest possible quotient, the latch 315 is released by the turning of a cam 319 on the decimal shaft 137 and the carriage moves to the right until the dog 69 abuts the pin 167. In each of these cases the number is printed by a printing mechanism 23, but no decimal point is printed. If the slide 181 is adjusted to the right of the position shown to indicate 1, 2, 3 or 4 decimal places, the latch 315 is freed and the carriage 30 moves to the right until the dog 69 abuts the appropriate pin 144. The dividend is then transferred into the main counter in the required position. This time, however, a decimal point is printed by the appropriate type bar 203. After input of the dividend, the divisor is set up and the result key (=) is depressed. This then inputs the divisor into the stationary register (not shown). The decimal shaft 137 is then locked in position by the latch 148 so that the carriage 30 is free to move to the right-hand end of its travel. It then reverses and the calculation starts, the carriage moving in steps into its left-hand position ready for printing the remainder from the main counter. This is printed without a decimal point as the remainder is not properly located with regard to the pre-set decimal point. Printing of the quotient from the revolution counter (not shown) then takes place and the decimal point is correctly placed for this, if one was originally set up. Multiplication.-This is similar to the arrangement described above, the multiplicand being set up and then transferred into the stationary register by depression of the multiply key ( x ). The result key (=) is then depressed and the multiplier, either called up from a storage register or set up on the keyboard, is put into the revolution counter. The calculation then takes place and the carriage 30 is moved to the right at the end of it. The drive is then reversed and if a decimal point has been set up, the carriage is stopped when the dog 69 abuts one on the pins 144, the shaft 137 being held in its operative position by the arm 175, and the product is printed from the counter. If no decimal point was set up the carriage moves into its left-hand position before printing the product. Sequence control.-A programme shaft 118, Fig. 5, can rotate once in twelve separate steps. Slides 104, 105, 106 have teeth 115, 116, 117 engaging toothed wheels 119, 120, 121, respectively. Normally they are held in the position shown in Fig. 5, but when one key is depressed the corresponding slide is released to follow a rod 111 moved under the action of a cam 112 on the main machine shaft 38. When the cam 112 rotates the rod 111 anti-clockwise about a shaft 110, the slide which has been released is moved to the left and its tooth steps the shaft 118 by one or two steps according to the position of the corresponding toothed wheel. The shaft is rotated through one step by depression of the division key (:) at which position various cams on it are arranged to input the dividend into the main counter. Depression of the result key then rotates it through two steps for the input of the divisor. After the calculation and with the result key still depressed the shaft is rotated through a further two steps for output of the remainder and a final single step for output of the quotient. During multiplication, the shaft is rotated through two steps at each operation. This shaft controls all the operation of the machine by means of cams 123, 127, 130 &c. Prevention of errors.-A number of balls 190 in a channel member 189 prevent any two function control keys being operated together. Moreover, once one of these keys has been depressed it is not possible to move the decimal point key as to do so requires downward movement of a lever 185 and this is prevented by the ball locking device 189, 190.