Patent ID: 8413921

Claim:
A supporting unit for a long piece of material comprising: a casing having an entrance and an exit through which a long piece of material is inserted, said casing comprising a member for an inserting side of the casing that has the entrance, a member for an outgoing side that is placed at an opposite side of the casing, from the member for the inserting side and has the exit, lateral members that enclose the space between the member for the inserting side and the member for the outgoing side, liners attached to an inner surface of each of the lateral members; each of said liners having openings, and affixing means that fix the member for the inserting side, the member for the outgoing side, and the lateral members; and a supporting mechanism for the long piece of material installed in the casing, said supporting mechanism comprising: a group of spherical bodies that is provided around a central axis of the long piece of material, a plurality of movable supporting members that are provided around the group of spherical bodies and having surfaces that contact a periphery of the group, and a plurality of biasing means that push each of the movable supporting members toward the central axis of the long piece of material, wherein the biasing means are coil springs and wherein back surfaces of the moveable supporting members, opposite from the surfaces that contact the periphery of the group of spherical bodies, have concave portions in which are mounted one end of the coil springs, and wherein opposite ends of the coil springs pass through said openings in the liners and are mounted on the inner surfaces of each of the lateral members.