Improvements in or relating to fluid counters

摘要

1,102,002. Reversible binary counter. R. W. WARREN. 11 May, 1965 [11 May, 1964], No. 19890/65. Heading G4P. A reversible binary counter has a plurality of pulse converters 121, 122 (Fig. 1b, and Fig. 2, not shown), 123, 124 (Fig. la) the state of each of which represents one of the digits of a binary number. In one embodiment (Figs. la and 1b) if, for example, the number stored in the counter is 5, i.e. converter 124 is in its " 0 " state (flow along channel 179), converter 123 is in its " 1 " state (flow along channel 178) converter 122 is in its " 0" state (flow along channel 175) and converter 121 is in its " 1 " state (flow along channel 174) and a count forward pulse is received at channel 172 the first converter 121 is switched to its " 0 " state. Since, on commencement of the pulse along channel 172, flow existed along channel 174, AND gate 132 is enabled, the resultant output flow along channel 190 switching the converter 122 to its " 1 " state. Since, initially, there was no flow along channel 176, AND gate 134 is not enabled and since there is consequently no flow along channel 192, AND gates 136, 138 remain closed and so converters 123, 124 do not change state. The final state of the counter is thus 0110 representing the digit 6. If the counter is in its 1000 state and a count backward pulse is received on the input channel 171, the converter 121 is switched to its " 1 " state. Since initially there was flow along channel 173, AND gate 131 is enabled so that the converter 122 changes state. Since there was also flow in channels 173, 175, AND gate 133 is open so that, on commencement of the count backward pulse, AND gate 135 is enabled to change the state of converter 123. Similarly gates 137, 139 are enabled to change the state of converter 124 so that finally the counter is in its 0111 state. In another embodiment (Fig. 2, not shown) input pulses are received only on one channel (201), flow in the input channels (213, 214) of a flipflop (211) indicating that the count is to be forwards or backwards respectively.