To prevent adhesion or a slip so as to facilitate displacement in the circumference direction and in the axial direction by positioning a lining provided with a low friction face between a seat and a bush of a housing and facing the low friction surface with the bush.

Desirably, a flatwise hose is used as an expansible tubular member 10, and loops adjacent to the hose are brought into tight contact with each other, and the hose is arranged so as to form a continuous coil of an expansible tube. A low friction material 15 is provided by a bushing of a split type ring shape so as to be placed on the flatwise hose 10 or a similar expansible member arranged in a space between the end parts mutually facing the inside of two sleeves 8, 9. In this way, the low friction material 15 is faced to the expansible member via its low friction surface and positioned with a packing, that is, a steel surface directed outward.