| 摘要 |
<p>PURPOSE:To measure and control chamber pressure with high accuracy without using any expensive absolute pressure gauge by controlling a main chamber according to absolute pressure and a subordinate chamber according to the pressure difference from the main chamber. CONSTITUTION:This controller is equipped with the main gas chamber CO, at least one of subordinate gas chambers C1 and C2 linked with the main gas chamber CO through individual partition valves GV1 and GV2 and differential gauges G1 and G2, a pressure control means 10 which measures the pressure in the main gas chamber CO and controls the pressure to specific pressure, and a partition valve control means 20 which controls the opening and closing of the partition valves GV1 and GV2. Then the main chamber CO is controlled according to the absolute pressure and the subordinate chambers C1 and C2 are controlled according to the differential pressure. Consequently, the need to use many expensive absolute pressure sensors is eliminated and high-accuracy pressure control is carried out.</p> |
