Patent GB-754104-A (GB)
Title: Improvements in or relating to type-composing machines
Inventor: HIGONNET RENE ALPHONSE EUGENE
IPC: B41B27/32
Filed: 1951-09-28
Abstract: 754,104. Photo-electric digital multiplier. HIGONNET, R. A. E., and MOYROUD, L. M. Sept. 26, 1952 [Sept. 28, 1951], No. 22704/51. Class 40 (3). [Also in Groups XVI, XIX and XX] In a photographic type-composing apparatus a keyboard selects characters which are represented in code in digital forms, indicative of the widths of the characters while the point set of a selected character is also represented in digital form. The product of these two values is produced by a photo-electric arrangement and passed on to an accumulator which stores the sum of the products fed to it. In one form of multiplier, there is provided a continuously rotating opaque disc 64, Fig. 8, having four groups of sixteen translucent slits 66 and a single slit 68. Photo-electric devices 70, 72 produce impulses corresponding to the passage of a slit 66, 68 respectively past a fixed position. Impulses from the device 70 pass through a conducting segment 76 of an insulating slipring 74 to one of four switches 100 and thence to the stages C1 to C8 of the accumulator, the switches being selectively closed according to one of the figures to be multiplied. However, the stages of the accumulator can be desensitized by a voltage on lead 84 connected to a flip-flop device 86. A binary counter 88 having stages D1 to D8 is connected to the device 70 through a delay device 91, and to a selector 28, which is set according to the other multiplying figure and connected to the device 72. In operation, assuming the figures to be multiplied to be 11 and 5, a timing device 94 synchronized with the disc 64 actuates the flip-flop device 86 to produce a de-sensitizing voltage on lead 84. An impulse due to slit 68 then passes through the selector 28 to the stages D1 and D4 of the counter 88. The device 70 then sends sixteen delayed impulses to the counter 88 and sixteen undelayed impulses to the C1 stage of the accumulator. The first ten impulses " fill up " the counter 88 to its maximum setting of 15, while having no effect on the accumulator owing to the voltage on lead 84. The eleventh impulse changes the counter to zero, and sends an impulse on lead 106 to reverse the device 86 and remove the voltage from lead 84. Because of the delay device 91, this impulse has no effect on the accumulator. The remaining five impulses are passed to the accumulator stage C1 to represent 5 x 1 or 5 units. The device 94 then cuts again to produce a voltage on lead 84. The second group of sixteen impulses results in five impulses being passed to stage C2. Since the switch to stage C4 is open the third group has no effect. After one revolution of the disc, the units represented by impulses passed to the accumulator amount to 5Î1, 5 X 2 and 5 Î 8, or 55. In a modification, Fig. 10, each group of slits 110 is radially staggered, and they each pass in front of a slot 112. A stepped cam 114 is set to obscure part of the slot, this action being equivalent to that of the selector 28. The impulses which are allowed by the cam to be generated are passed to the accumulator stages by the means shown in Fig. 8 Specifications 685,310, 691,738, 691,762, 619,910, [all in Group XX], and 754,208, [Group XIX], are referred to.