| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an expansion jib showing improved resistance to warping and therefore suitable for supporting an extreme load in, for example, pull-in jib operation or in a wire supporting type system or when positioning the jib supporting a substantial load while positioned in an almost vertical direction. <P>SOLUTION: The expansion jib for a crane such as a vehicle crane has an upper-side contour portion and a lower-side contour portion to be combined therewith. The lower-side contour portion consists of a plurality of shell segments each of which has an outward curved shape. The upper-side contour portion has a plurality of outward curved shell segments having contact with one another at obtuse angles. <P>COPYRIGHT: (C)2003,JPO</p> |
