| 摘要 |
PROBLEM TO BE SOLVED: To execute the open/close control sequence of each valve 7-9 in an isolation vent valve system 5 surely in safety through a simple arrangement. SOLUTION: This valve controller comprises a pulse generator 21 generating a pulse signal for bringing a preset specified time after rising of a supply command signal S0 before full-close of a C valve 9 into on state based on the supply command signal S0 for bringing the interval from start of pressurized air supply to the end thereof into on state, an OR circuit 24 for delivering the logical sum of a signal S19 and the logical product of the pulse signal and a signal S14 to a B valve 8, an off delay timer 28 for delivering a signal S12 obtained by delaying the falling of the logical product signal S20 of the supply command signal S0 and a signal S16 by a specified time to an A valve 7, and an on delay timer 26 for generating a signal S13 by delaying the rising of the signal S20 by a specified time and delivering it to the C valve 9.
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