| 摘要 |
PROBLEM TO BE SOLVED: To provide an easy-to-manufacture expansion screw for an expandable dowel sleeve, which is stably held in the dowel sleeve for generating high expansion force, and also to provide a fixing device having the same. SOLUTION: The expansion screw 11 for the expandable dowel sleeve 31 comprises a shaft 12, a screwing engaging means 15 provided at a first end 13 of the shaft 12, and a first thread 19 in at least one line extending from a second end 17. In a region of the first thread 19 in at least one line, apart from the second end 17, a screw portion 21 is provided which has another second thread 23 in at least one line. Preferably, an outer diameter A of the second thread 23 in at least one line is equal to an outer diameter A of the first thread 19, the pitch gradient of the second thread 23 in at least one line is equal to the pitch gradient of the first thread 19 in at least one line, and all threads 19, 23 have the same flank angle C. COPYRIGHT: (C)2008,JPO&INPIT
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