| 摘要 |
<p>A water craft, e.g. a tug, has a rudder propeller or other thrust generator rotatable about a vertical axis, for steering, and arranged under the front half of the craft. The thrust generator is arranged under a shaft construction comprising an outer wall which is a substantially fixed component of the hull and has its upper end above the water line, and an inner wall mounted in the outer wall so that it can be raised. The inner shaft wall is supported by thrust blocks in the space between the walls. The thrust generator is mounted on the inner shaft wall and is drivable from within the craft via a transmission passing through the shaft construction. The rotating thrust generator occupies a space whose horizontal extent is smaller than that of the clear space which exists within the outer shaft wall when the inner shaft wall is raised.</p> |
