| 摘要 |
PURPOSE:To attain a displacement designated by a digital signal with high accuracy and with a simple constitution by controlling a large number of steps with a small number of electric control signals. CONSTITUTION:The supply air which underwent the pressure control through a pressure control valve 27 is sent to a drive actuator mechanism 26 as well as to a position detecting cylinder 19 through a throttle 28. The electric signal supplied from outside is sent to solenoid valves V1-V3 in the form of binary signals to actuate an SW drive actuator 34 which drives changeover switches SW1- SW3 respectively. Then a position detecting nozzle 18Sn is turned on, i.e., made conductive with the air by means of a binary control logic circuit. The decision for ON position of the nozzle 18Sn (S0-S7 with 8 steps) can be freely controlled with the ON-OFF combination of a solenoid valve 35 (V1-V3 with 8 steps) which drives the actuator 34, i.e., the combination of digital signals 0 and 1. |
