Patent GB-886901-A (GB)
Title: Improvements in electrical counters
Inventor: HALLIDAY ANTHONY MARTIN
IPC: G06K15/06
Filed: 1957-11-12
Abstract: 886,901. Electric selective signalling systems. NATIONAL RESEARCH DEVELOPMENT CORPORATION. Feb. 12, 1959 [Nov. 12, 1957], No. 35167/57. Class 40 (1). An electric pulse counter comprising a series of cascaded multi-cathode counting tubes is provided with means for recording the count, including a bank of photo-cells, an opaque movable mask with a series of windows arranged in accordance with a code, gate means for energizing the photo-cells from the counting stages and a group of pen electrodes adapted to supply recording potentials to a travelling web of electro-sensitive material. As described, the recording mechanism comprises five electrode pens 1-5 arranged transversely across a continuously moving strip 6 of electro-sensitive paper, each pen being energized through a corresponding brush 11-15 bearing on a commutator 7 which carries three rows 8-10 of five contacts 16 each, the contacts 16 covering an angular spread of about 270 degrees of the commutator 7, and being energized from a common brush 17. The brush 17 is supplied via a circuit 18 with pulses derived from a bank of photocells 20-29 corresponding to the digits 0-9 located in a line parallel to the axis of a cylindrical opaque mask 19 having ten circumferential rows 30-39 of holes, one row for each photo-cell, the holes in each row being arranged in a code adapted to supply energizing pulses to the pen electrodes 1-5 in such manner that dots are recorded on the strip 6 to represent the arabic numeral to which the row and associated photo-cell correspond. A brush contact or further photo-cell 40 supplies a pulse to a programme counting tube 42 once each revolution of the mask 19, the cathodes of the tube 42 controlling a relay 45 adapted to control energization of the photo-cell 40, a relay 46 controlling zeroizing of the counting tubes 47, 48 &c. The tube 42 also controls a circuit 85, Fig. 2, adapted to supply pulses alternatively to other counting registers (not shown), and gates such as 60 . . . 69 in the cathode circuits of the individual counting tubes thereby effecting sequential scanning of the tubes 47, 48 &c. The counting tube 47 has its reading recorded when the programme tube 42 causes cathode follower 80 to conduct thereby enabling diodes 70-79 to pass potential from the operative cathode of the tube 47 to a photo-cell 20-29 which is thereby primed to produce the required code pulses when illuminated through the windows in the mask 19. The code pulses selectively energize the pen electrodes 1-5, the circuit being completed via the electro-sensitive paper 6 and a conductive plate 89, Fig. 2. A modification of the counting tube cathode circuit for use with " slow " counting tubes is described (Fig. 2A, not shown). In an operating cycle, the programme tube 42 steps on to cause the circuit 85 to supply the pulses to be counted to a second counting register (not shown), when the first register comprising tubes 47, 48 &c. is to be read. The tubes 47, 48 &c. then have their readings recorded successively, the recording of each digit corresponding to a single rotation of the mask 19 and commutator 7 which are both driven by a motor 92. When all the tubes 47, 48 &c. have been scanned, the programme tube 42 energizes the relay 46 which zeroizes the tubes 47, 48 &c. and may also change the state of the circuit 85. The relay 45 is also energized to remove potential from the photo-cell 40. The next recording operation may follow automatically or may be manually controlled. In a modification (Fig. 3, not shown), there are three pen electrodes for each digit, but a group of three pens is provided for each counting tube in a register. In a further modification (Figs. 4 and 5, not shown), the mask is disc-shaped, and a bank of photo-cells is provided for each counting tube.