| 摘要 |
<p>An operating mechanism for a rotary valve comprises a rack 18 reciprocatable within a housing 10 by an actuator 20 axially movable from outside the housing through an access aperture 30. The rack engages a pinion 14 connectable with a valve stem 16. A bellows seal 24 surrounds the actuator and is sealed at one end to the rack and at the other end to the housing about the aperture to prevent escape of any noxious fluids which might escape past the valve gland into the operating mechanism housing when sealingly mounted to the valve body.</p> |
