GB592174A - Improvements in or relating to electric impulse responsive apparatus - Google Patents

Abstract

592,174. Counting-apparatus; transfer mechanism. NATIONAL CASH REGISTER CO. May 19, 1944, No. 9739. Convention date, June 4, 1941. [Class 106 (i)] [Also in Group XL] A plurality of gaseous electron tubes are arranged in an endless chain so that they become conductive in sequence and means are provided whereby as one tube becomes conductive all others which were previously conducting are extinguished, the cathodes of the tubes being connected through capacitors to a common conductor. As shown in the Figure, positive impulses are impressed on the grids of all the tubes through conductor 43 and condensers 40. By closing switch 42 and grounding the grid of tube (0), which was previously at a lower negative potential than its cathode, the tube (0) is fired and becomes conductive. Its cathode potential immediately rises considerably, causing a rise at point 33 and at the grid of tube (1), so that it becomes more positive than the grids of all the other tubes. When a positive impulse of sufficient value is impressed on conductor 43, tube (1) alone will fire. Its cathode potential will rise causing condenser 29 to charge and the potential of conductor 31 to rise so that the cathode of tube (0), and any other tube which happens to be conducting, momentarily becomes more positive than its anode and thus extinguishes conduction. The grid potential of the following tube (2) will rise, preparing it for conduction on the next impulse. A self-extinguishing tube (T) is provided as shown which is fired at the same time as tube (0), that is, at the end of each cycle of operation, so as to provide a carry-over or transfer for actuating a second ring of tubes over conductor 62. The tube T is probably extinguished .due to back voltage caused by temporary induction phenomena in the cathode circuit when the condenser 52 discharges through the tube. To prevent any of the tubes firing out of order due to potential surges in the circuit, stabilizing resistors 30 may be included, as shown, or a single resistor placed in series with resistance 25 in the anode supply line as in Fig. 2 (not shown).