| 摘要 |
A manual valve operator with override clutch apparatus is disclosed for selectively actuating a valve. The apparatus includes an operator housing defining an enclosure. An input shaft is rotatably supported by the housing and a worm wheel has a first and a second side, the second side of the worm wheel defining a clutch drive. The worm wheel is disposed within the housing and intermeshes with the input shaft such that when the input shaft is driven, the input shaft drives the worm wheel and the clutch drive about a rotational axis. A sleeve has an outer surface which defines an annular groove. The sleeve has a driven end and an output end. The driven end of the sleeve cooperates with the clutch drive of the worm wheel for selective engagement of the clutch drive and the driven end of the sleeve. A clutch actuating handle is rotatably supported by the housing. The clutch actuating handle has a first and a second end. The second end of the clutch actuating handle defines an offset clutch driver which slidably cooperates with the annular groove of the sleeve. The arrangement is such that when the handle is rotated relative to the housing, the offset clutch driver rides within the annular groove for urging the sleeve axially along the rotational axis so that in a first axial disposition of the sleeve, the clutch drive of the worm wheel and the driven end of the sleeve are engaged relative to each other so that the sleeve is rotated by the worm wheel about the rotational axis. However, when the sleeve is disposed in a second axial disposition thereof, the driven end of the sleeve is disengaged relative to the clutch drive of the worm wheel. A driven shaft has a first and a second end, the second end of the driven shaft being connected to the valve. The driven shaft extends coaxially through the sleeve, the driven shaft being keyed to the sleeve such that relative rotation between the sleeve and the driven shaft is inhibited while axial movement of the sleeve relative to the driven shaft is permitted. The arrangement is structured such that when the sleeve is in the first axial disposition thereof, the worm wheel drivably rotates the sleeve so that the rotating sleeve rotatably drives the driven shaft for actuating the valve. Also, when the sleeve is in the second axial disposition thereof, the driven end of the sleeve is disengaged from the clutch drive of the worm wheel so that rotation of the sleeve and the driven shaft keyed thereto by the input shaft is inhibited. |
