| 摘要 |
<p>PURPOSE: To provide a pilot type 2-port vacuum valve stably setting inside a vacuum chamber to a desired pressure without stirring up particles by a simple constitution and a simple operation. CONSTITUTION: This pilot type 2-port vacuum valve is provided with a main valve 24 fully opening/closing a main channel B connecting a first and second ports 3 and 4, a sub-valve 9 restrictively opening/closing a sub-channel A having an opening area smaller than the main channel B, a main valve drive part connected to the main valve 24 via a first shaft 6 and driving the main valve 24 by a hydraulic pressure, first elastic members 10 and 14 energizing the first shaft 6 in the directing of closing the main valve 24, a sub-valve drive part connected to the sub-valve 9 via a second shaft 7 and driving the sub-valve 9 by the hydraulic pressure, a second elastic member 15 energizing the second shaft 7 in the direction of closing the sub-valve 9, and an operation port 35 introducing the pressure fluid to the main pressure operation chamber 47a and sub-pressure operation chamber 48a.</p> |
