| 摘要 |
A radially expandable assembly comprises a first elongate member (3, 27, 55, 83), a second elongate member (1, 29, 59, 93) movable in an axial direction relative to the first member, one of the first and second members being provided with a substantially conical surface (11, 41, 63), and a radially expandable and contractable component (17, 45, 67, 95). The radially expandable and contractable component comprises a plurality of part-cylindrical members (19, 47, 69, 97, 103) which together extend substantially in a circle and are provided with a resilient member (21, 21', 21", 49, 71, 99, 109) biasing the part-cylindrical members radially inwardly. Consequently, movement in a first direction of the member provided with the substantially conical surface (11, 41, 63) causes the surface to engage with a radially inner surface of the radially expandable component (17, 45, 67, 95) so as to move the part-cylindrical members (19, 47, 69, 97, 103) radially outwardly beyond a periphery of an outer of the first and second members and movement in a second direction causes the part-cylindrical members to contract radially inwardly under the biasing effect of the resilient member (21, 21', 21", 49, 71, 99, 109) such that the part-cylindrical members do not extend outwardly beyond the periphery of the outer of the first and second members. |
