For example, a shot-blasting device polishes a wire by throwing shot-blasting media against it, where the wire is a long piece of material being pulled and tensioned. This shot-blasting device comprises a wire-feeding device, a device for throwing shot-blasting media, and a device for winding a wire. The wire-feeding device, which is provided on one side of a polishing chamber, through which side the wire enters, causes a wire that has been wound in a coil to run in almost a straight line, and feeds it into the chamber. The device for throwing the media, which is installed inside the polishing chamber, throws them at the wire that is coming from the wire-feeding device and running through the chamber. The device for winding a wire, which is provided on the side of the polishing chamber from which the wire comes out, reels in the wire that has been processed by the shot-blasting. The shot-blasting device has guiding equipment so as to prevent the wire from any swinging that could be caused by shot-blasting media throwing shot against the wire.
There are many kinds of guiding equipment using various mechanisms. For example, an ancillary jig for preventing swings comprising a hollow cylinder, a plurality of balls, and a cap, may be used as guiding equipment (see the Publication of Examined Utility Model No. 63-2241). The hollow cylinder has a through-hole, and a convex conic surface is formed on one end of the cylinder. Two or more V-shaped grooves are made on the conic surface toward its central axis. In each groove a ball is inserted so that a part of it can protrude through the through-hole. The cap, which is axially screwed in one end of the cylinder, keeps these balls on the conic surface by a concave conic surface.
However, before being put in the wire-feeding device, such a wire that is wound in a coil has a plurality of crooked parts. They are locally made from straps for binding coils when they are transported from their manufacturer, for example. Even though the wire feeding device tries to make the wire in a straight line, it is very difficult to completely remedy the crooked parts and do so. If the wire having these crooked parts were to pass through the guiding equipment at a velocity of 5-150 m/min, it might be scratched by the protruding parts of the balls and damaged, because there is no radial play between the wire and the balls.
The present invention was conceived so as to resolve the above problem. Its purpose is to provide a supporting mechanism that decreases the swings and deflections of a long piece of material that arise when the material is processed, as well to prevent scratches of the material. Also, it is to provide a supporting unit using this mechanism and to provide a method for preventing swings and deflections of the long piece of material using this unit.