| 摘要 |
<p>A movable joint 10. The joint comprises a socket member 12 having a cavity. Rotation member (14, FIG 14) is positioned and able to rotate within the socket member. The rotation member has a cylindrical bore configured to receive a tubular member 100. A locking mechanism releasably locks a tubular in the cylindrical bore. When a tubular is locked in the bore the tubular and rotation member are fixed relative to one another and are rotatable relative to the socket member 12. The rotation member may be a ball which has three rotational degrees of freedom. The rotation member may have recesses 24 in its inner surface 22 which house a roller 26, and a cage with windows connected to it which can form the locking mechanism. At the lower end of each recess 24 a roller may protrude through the window in the cage.</p> |
