| 摘要 |
<p>The actuator (2) can be used to apply fluids to the web of a papermaking machine. The actuator comprises a housing (4) having a first inlet (16) connectable to the fluid source and a second inlet (10) connectable to a pressure source. A resilient bellows structure (30) extends between the first and second inlets within the housing to define an internal region of the bellows structure in sealed communication with one of the first and second inlets and an external region of the bellows structure in sealed communication with the other inlet. A valve member (50) adapted to move with the bellows structure is provided to open and close the first inlet to vary the flow of fluid from the fluid source and maintain a pressure related to a balance of forces of the bellows structures. An outlet (58) from the housing in communication with the first inlet permits the exit of the flow of fluid to a flow controlling orifice. A pneumatic control signal provided to the second inlet controls expansion or contraction of the bellows structure.</p> |
