| 摘要 |
PROBLEM TO BE SOLVED: To provide a wood crack preventing screw for effectively preventing the crack of a wood. SOLUTION: A screw stem portion 1 having a spiral screw thread 2 formed on the outer periphery is cut at its front end side, and the front end of a cut face 3 is offset to the outside of an axial center P of the screw stem portion 1. The cut face 3 is constituted by two faces each having an angle 10 of 90°-180°. The front ends of these two faces 3a, 3b can be offset to the outside of the axial center P of the screw stem portion 1. COPYRIGHT: (C)2006,JPO&NCIPI
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