| 摘要 |
PROBLEM TO BE SOLVED: To improve durability of a rubber-like elastic body by expanding an inner cylinder in diameter in place of drawing of an outer cylinder or in combination with this drawing by expanding the inner diameter and imparting preliminary compression to the rubber-like elastic body. SOLUTION: An inner cylinder 2 and an intermediate cylinder 4 are formed on a cylindrical parts in which a liquid sealing part is formed around a rubber-like elastic body 5. A tube expanding bar 8 is inserted from one end part of the first inner cylinder 2 of the cylindrical parts and the inner cylinder 2 is expended in diameter. Subsequently, the tube expending bar 8 is pulled out, the tube expanding bar 8 is inserted from the opposite side of the inner cylinder 2 and the tube expanding bar 8 is passed through to the last so as to expand the remaining part in diameter. Next, after the second inner cylinder 2 is internally fitted and press fitted into the inner cylinder 2 after the expanding in diameter, an outer cylinder is externally fitted in liquid such as ethylene glycol liquid and drawing is performed for the outer cylinder so as to radially reduce the outer cylinder in diameter. As a result, a rubber bush 1 in which liquid is filled in the liquid sealing part and preliminary compression is imparted to the rubber-like elastic body 5 by the expanding of the inner cylinder 2 in diameter and drawing of the outer cylinder is completed. Therefore, durability can be remarkably improved by uniform preliminary compression. |
