| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a rolling bolt of a double thread configuration with improved durability, mechanical strength, and productivity. Ž<P>SOLUTION: In the rolling bolt of the double thread configuration, a coarse thread of a standard first pitch, and a fine thread of a second pitch being smaller than the first pitch are manufactured on an outer circumference part by rolling. In a thread crest 53 of the coarse thread, a thread face 53c is formed in a trough bottom side from a substantially center part of the thread crest. Thread ridges 52 of the fine thread are protrusions periodically formed in a top side from the substantially center part of the thread crest of the coarse thread. A small crest side of crest parts on both sides of a trough part of the fine thread formed on the thread crest of the coarse thread is formed as a flat part conforming to a height of a trough bottom part of the thread crest 52 of the fine thread within a predetermined angle range. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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