Patent GB-718159-A (GB)
Title: Electrical impulse counting arrangements
IPC: H01J17/00
Filed: 1952-11-13
Abstract: 718,159. Electronic counting-apparatus. NATIONAL CASH REGISTER CO. Nov. 13, 1952 [Dec. 4, 1951 ; Dec. 4, 1951], No. 28602/52. Class 106 (1). [Also in Groups XL(a) and XL(c)] In an electronic counting arrangement of the kind which includes a series of tubes rendered conducting seriatim in responses to impulses and with means for automatically priming the tube next to be rendered conducting, alternate tubes are interconnected to form two operational groups to which operating potentials are alternately applied by an impulse responsive device having two modes of operation and caused to change from one mode to the other alternately in response to successive impulses, so that during one mode of operation a tube in one group is rendered conducting to prime a tube in the other group which is caused to be rendered conducting when the device changes its mode of operation in response to the next impulse. In a first embodiment pulses from a source 67, Fig. 1, cause a brief conduction in a pulse shaping tube 52 connected in a selfextinguishing circuit, and a corresponding signal passes from the cathode 60 to a point 83 which is connected to the grids of two tubes 50, 51 arranged as a trigger pair with cathode loads 70, 71 and an interconnecting capacitor 73 which serves to transmit an extinguishing pulse to the conducting tube of the pair when the other tube is turned on by an input pulse. In a counter decade of tubes 0 ... 9, even-numbered anodes are connected, via a common resistor 90, to the cathode of tube 30, and odd-numbered anodes via a resistor 91 to the cathode of tube 51, so that when one of the counter tubes (e.g. No. 1) is conducting the associated trigger tube (51) is also conducting and, since the opposite tube (50) is not, the counter tubes (0, 2) on either side of the conducting tubes have their anodes at substantially earth potential By virtue of interconnection between the shield grid of each tube and the control grid of the next higher tube (excepting the 9 to 0 stage) the tube at the RH side of the conducting tube is primed to respond when the next input pulse reverses the trigger pair 50, 51. Transfer to the next denomination when the discharge passes from tube 9 to tube 0 is provided by a second pulse shaping tube 53 connected in a self-extinguishing circuit, the grids of this tube receiving an impulse from a potentiometer connection 114 in the cathode circuit of the tube 0. Output from the tube 53 is via a connection 116. In a second embodiment the trigger pair 50, 51 have earthed cathodes and resistive anode loads with a capacitor interconnection for transmitting extinguishing pulses. The even-numbered and add-numbered counting tube anodes are connected to the respective anodes of the trigger tubes. In a third embodiment cold-cathode discharge tubes, constructed as shown in Fig. 5, form the counter decade. A probe electrode P between the cathode K and the anode A is connected to an igniter electrode I, of the next higher tube in each ease, and the firing of the tubes is controlled by a thyratron trigger pair as in the first embodiment. A second igniter electrode 12 and an auxiliary anode Ax are not used.