| 摘要 |
PURPOSE:To manufacture a bent form of heat-shrink tubes having a given shape, e.g., with a fixed curvature, by a method in which a molding cylinder consisting of a bent tube with many internally through small holes in its side face is set in an isolating manner from the inner wall of an out tube consisting of air-tight walls not to be deformed even when evacuated to vacuum. CONSTITUTION:An original pipe 7 is thrust through a molding cylinder 2 and fixed to the pipe fixers 32 and 32' of a cover 3. The pipe 7 is beforehand heated to more than its softening temperature. When the air-tight space formed by an outer tube 1, the pipe 7, and the cover 3 is evacuated to a vacuum through an exhaust pipe 41, the pipe 7 is expanded to closely adhere to the inner wall of the cylinder 2, as shown by the full line, where the inner wall of the cylinder 2 serves as a mold for the pipe 7. After the pipe 7 in the expanded state is hardened by cooling, the fixers 32 and 32' of the cover 3 are released and opened and the molding is taken out. A given bent form of tubes can thus be obtained by very simple operations. |
