To provide a screw thread structure allowing fastening strength to be compatible with maintainability requested when the structure is used.
The thread part 14 of a bolt 10 is set to a pitch threaded with a female screw part 15 when it is contracted at a prescribed temperature. The female screw part 15 forms such a clearance C that can absorb the increased amount of the pitch of the thread part 14 when it is naturally expanded at a room temperature, and the shaft diameter D of the screw part 14 by natural expansion is set slightly larger than the root diameter d of the female screw part 15. Since the connection of the screw part 14 of the bolt 10 with the female screw part 15 threaded with the screw part 14 is maintained by utilizing heat contraction, a rigid fixing structure can be provided and also since the bolt 10 is re-cooled by utilizing a hole formed in the bolt 10, the screw part 14 can be de-threaded from the female screw part 15.
| JPH04224785A | 1992-08-14 | |||
| JPS59191406U | 1984-12-19 | |||
| JPS59168014U | 1984-11-10 | |||
| JPS58162310U | 1983-10-28 | |||
| JPS57194833A | 1982-11-30 |
Takao Ito
Jiro Higuchi