摘要 |
Controlled variable table data, which consist of pulse number data corresponding to the maximum controlled variable of a fluid valve and divided into N divisions in each of which given pulse number data are set, are stored in a memory so that the sum of the given pulse number data in the N divisions may be equal to the number of pulses for giving a given controlled variable to the fluid valve. On the other hand, period table data, which consist of pulse interval data divided into divisions corresponding in number to the divisions of the controlled variable table data for determining a given control pattern, are stored in another memory. The fluid valve is controlled by successively generating pulses corresponding to the pulse number data in the individual divisions of the controlled variable table data at pulse intervals set in the individual divisions of the time length table data, driving a pulse motor by means of the generated pulses to control the flow rate and fluid pressure, counting the pulses, converting the count into an analog signal, thereby driving an actuator for the fluid valve.
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