| 摘要 |
<p>A driven barrel of a winch device includes a closed cylindric space (16) which is concentric with the barrel and accomodates a piston (17), which can move on an axis (12) from one end of the cylindrical space to the other in non-rotatable connection (19, 20) with the inside of the barrel. The axis (12) has screw threads (15) and the piston (17) has a center bore with screw threads meshing with the screw threads of the axis, whereat the cylindric space contents a fluid and the piston (17) is given a leak from one side of the piston to the other side. In order to stop the loaded rope to be unwound from the barrel if the rotation speed of the barrel should increase over a certain value the leak is in the form of a canal (21) which accomodates a valve means including a valve housing and a valve body (22). The valve means stops the fluid flow over the valve body in one direction at a certain pressure drop over the valve body.</p> |
