| 摘要 |
This invention relates to apparatus for controlling the inclination of a pivotable member relative to a fixed structure, in particular the inclination of the jib of a crane. Control is effected by two jacks, each being connected by one end to the jib and by the other end to the body of the crane. The points of attachment of the jacks to the jib and the pivot axis of the jib define the vertices of two deformable triangles, one preferably being right-angled when the other has been flattened to a straight line. The lifting torque of a crane can thereby be substantially constant for all values of jib inclination. |
