| 摘要 |
<p>A valve body (12) includes a passageway (18) for the flow of fluid therethrough, a valve member (26), such as a ball valve member, is positioned in the passageway (18) for rotatable movement about a first rotational axis (38) between an open position and a closed position to open and close the passageway (18). An actuator (30) orbits about the first axis (38) to move the valve member (26) between the open and closed positions. A bent unitary valve stem (28) extends between the valve member (26) and the actuator (30). A lower end (40) of the unitary valve stem (28) is aligned with the first axis (38) and is connected to the valve member (26) for rotation with the valve member (26). An upper end of the unitary valve stem (28) is aligned with a second axis (44) angularly displaced from the first axis (38). A bearing assembly (46) retained in the actuator (30) connects the stem upper end (42) to the actuator (30). A bellows (50), bent to follow the curvature of the valve stem (28), surrounds the valve stem (28) to form a primary pressure boundary hermetically sealing the valve stem (28). A housing (82) surround the bellow (50) forming a secondary pressure boundary with the handle (68) of the actuator (30) and accompanying static and dynamic 0-ring seals. A lower end of the bellow (50) is connected to the valve body (12). An upper end of the bellow (50) is connected to the bearing assembly (46) which rotatably supports the bellow (50) in the actuator (30). The actuator (30) orbits about the first axis (38) to open and close the valve while the upper end of the bellows (50) rotates about the second axis (44). Turning the actuator (30) transmits torque through the pressure boundaries without applying torque to the bellows (50).</p> |
