| 摘要 |
Low particulate slit valve system and method for controlling the closure pressure applied to a slit valve. An apparatus in accordance with the present invention includes a barrier having a slit valve aperture, a valve seat surrounding the aperture, a closure movable towards and away from the valve seat, a sensing mechanism for determining the pressure differential on the two sides of the barrier, a processing unit responsive to the pressure differential and operative to produce a control signal, and a valve actuator responsive to the control signal and operative to control the force applied to the closure. The method of the invention includes determining a first fluid pressure on a first side of the barrier, determining a second pressure on a second side of the barrier, and applying a closure pressure to the closure which is related to the pressure differential between the first fluid pressure and the second fluid pressure. If the pressure differential is low, zero or very near to zero pressure is applied to the closure to seal the aperture. If the pressure differential is high, a proportionately larger pressure is applied to the closure.
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