GB766311A - Improvements in or relating to electronic counters - Google Patents

Abstract

766,311. Electronic counting apparatus. IMPERIAL CHEMICAL INDUSTRIES, Ltd. Nov. 29, 1954 [Nov. 30, 1953; April 7, 1954], Nos. 33155/53 and 10176/54. Class 106 (1). In counting-apparatus comprising two or more polycathode gas-filled tubes, tens transfer is effected between adjacent orders by applying the signal from the lower order zero cathode together with signals delayed relative to those applied to the second guides (i.e. the transfer electrodes next before the cathodes in the adding direction) to a first coincidence circuit and by applying signals synchronous with the second-guide signals together with a delayed zero-cathode signal to a second coincidence circuit, output signals from the two coincidence circuits being applied primarily to the first and second guides of the higher order tube respectively to add or subtract a transfer digit according to whether the lower tube is counting additively or subtractively. The limits of the delays referred to (approximately one-third of the time for one count at the maximum speed), are specified. For additive counting. negative pulses are applied to the first guides G1 of a lower order tube V1 and delayed signals are applied to the second guides G2. The latter, further delayed by a circuit R1, C1, X1, or a monostable trigger pair, are applied to the first (pentode) coincidence gate V3 to which the zero cathode of the tube V1 is directly connected. As the counting-tube discharge reaches the zero cathode, coincidence occurs and the output of the pentode V3 is passed through a shaping stage V2 and applied to the first guides G3 of the next counting tube V4, a corresponding delayed signal being applied to the second guides. In subtractive counting, negative pulses are applied to the second guides G2 of the tube V1 and delayed signals to the first guides G1. The zero cathode is connected through a delay circuit R2, C2 to the second pentode coincidence gate V6, to which are also applied positive signals, synchronized with the negative second-guide pulses, from a source 30 (e.g. the other anode of a shaping tube feeding-in the negative pulses to be counted). In this case, coincidence occurs as the counting-tube discharge arrives on the adjacent second guide after leaving the zero cathode. The output of the pentode V6 is passed through a shaping stage V5 and applied to the second guides G4 of the next counting tube V4. The same signal, delayed, is applied to the first guides G3. By reversing all the potentials, the counting tubes may be operated as polyanode tubes. The counter may be incorporated in apparatus for determining the position of a shaft, e.g. in weighing-apparatus. Specifications 757,105, 757,922, [both in Group XL (b)], and 771,057 are referred to.