| 摘要 |
PURPOSE:To enable to keep the quantity of input current and the quantity of control air substantially in a proportional relationship, by providing guide for attaining uniform distribution of pressure acted to the upstream sides of valves for opening and closing respective orifices. CONSTITUTION:By providing guides 17, 18 on the upstream sides of orifices 14, 15, distribution of pressure acted to the upstream sides of the orifices 14, 15 from an air passage 12 can be made uniform. Since this enables a valve supporting member 7 to operate smoothly at a correct position, the quantity of control air can be made proportional to the quantity of electric power supplied to a coil 3 of a proportional electromagnetic driving means, and at the same time, hunting of control-air flow can be also prevented. |
