| 摘要 |
<p>A direct operated valve assembly (10, 210, 310) is provided including a valve body (12, 212, 312) having a pressurized inlet port (30, 230, 330) in communication with a source of pressurized air, a cylinder port (32, 232, 332), a valve bore (36, 236, 336) extending axially within the valve body, and a valve member (46, 246, 346) supported within the valve bore and movable between predetermined positions within the valve bore to selectively direct pressurized air from said inlet port through the cylinder port. An actuator (14, 214, 314) is mounted to the valve body for moving the valve member in a first direction and a biasing member (66, 266, 366) is disposed between the valve member (46, 246, 346) and the valve body (12, 212, 312) to provide a biasing force to the valve member in an opposite direction. Also, an air-assist passage (94, 294, 394) is included for providing a source of pneumatic pressure that acts in combination with the biasing member (66, 266, 366) to operatively move the valve member (46, 246, 346) in a direction opposite to the movement induced by the actuator (14, 214, 314). <IMAGE></p> |
