| 摘要 |
PURPOSE:To prevent intrusion of expanding rubber into the boundary of tubes by sticking an inner tube fast to a jig and to improve the quality in manufacturing a composite tube by a rubber expanding process by placing a packing between the end face of the inner tube which is slightly longer than the outer tube and a jig. CONSTITUTION:An outer tube 2 and an inner tube 1 which is slightly longer than the outer tube 2 are contracted in a die 3 to bring the end face of the inner tube 1 into contact with a packing 12 placed on the bottom of the die 3. Expanding medium rubber 4 which is slightly longer than the inner tube 1 is inserted into the inner tube 1 and fixed to the die 3 by a cover through a packing 11 and a strap 7 in the upper part of the inner tube 1. The end face of the inner tube 1 is closely stuck to an adjoining jig by packings 11, 12. Then, a punch 5 is pressed down to give compressive load to the expanding medium rubber 4 through seal rubber 8. The medium rubber 4 is expanded, and the inner tube is expanded to stick it closely to the inner peripheral face of the outer tube 2. As the end face of the inner tube 1, a strap 7 and the bottom face of the die 3 are always in close contact, the expanding medium rubber does not flow out, and harmful substances do not interpose in the boundary of composite tubes. |
