GB786166A - Improvements in electronic counters - Google Patents

Abstract

786,166. Electronic counting apparatus. IMPERIAL CHEMICAL INDUSTRIES, Ltd. Sept. 16, 1955 [Sept. 17, 1954], No. 26980/54. Class 106 (1). In a counting apparatus adapted for both positive and negative operation and comprising at least two multicathode counters, the carry (or borrow) between a lower counter and the next higher counter is effected by allowing a pulse through a first gate (or a second gate) to the next higher counter to cause addition (or subtraction) in that counter when any pulse to be added (or subtracted), or any pulse coincident therewith, overlaps in the first (or second) gate the trailing edge or a pulse derived from the trailing edge of the signal leaving the cathode preceding the zero cathode (or the zero cathode) of the lower counter. As described, the movements of a disc 10 coupled to the indicating shaft of a weighing machine, for example, are detected by photo-cells cooperating with radial markings on the disc whereby two overlapping trains of pulses are applied to a discriminating device 11 which provides corresponding signals on one only of its two output channels according to the direction or rotation of the disc 10, These signals are fed to " first " gates 12, 13, associated with the respective counting tubes C1, C2, &c. when the disc 10 is moving in the positive direction and to " second gates 14, 15, &c. when the disc is moving in the negative direction. A further supply of pulses is fed via a shaping circuit 16 to all the gates 12, 13, 14, 15, &c. and the ninth cathode K9 of each tube C1, C2, &c. is connected to the " first " gate 13, &c. of the next higher tube, while the zero cathode K0 of each tube C1, C2, &c. is connected to the " second " gate 15, &c. of the next higher tube. Thus, " carry " or " borrow " pulses are gated through to higher tubes simultaneously with the occurrence of the counting pulse giving rise to the " carry " or " borrow ". In a more detailed diagram (Fig. 3, not shown), multigrid valves are used as gates and mono-stable hard-valve trigger circuits develop pulses derived from cathodes K0 and K9. R.C. delay networks including blocking diodes serve to produce double pulses for the two guide electrode systems from each signal input pulse. Specifications 757,922, [Group XXXVII], and 771,052, [Group XXXVIII], are referred to.