| 摘要 |
PROBLEM TO BE SOLVED: To provide a wood screw that suppresses increase in insertion torque even in an application in which high viscosity rubber for waterproof and a wood abut on each other and are penetrated.SOLUTION: A wood screw 10 includes a head part 11 receiving turning force, a shaft part 12 in which a shank 12a is a columnar shape, a screw tip part 13 in which a shank 13a is a conical shape, first and second screw threads 14, 15 straddling the screw tip part 13 and the shaft part 12. The screw tip part 13 includes at least four V-shaped grooves 16 formed rotationally symmetrically with the rotational axis of the shank 13a as a center and with equal intervals so as to extend to the tip of the screw tip part 13. The wood screw 10 rotates by receiving turning force at the head part 11, and thereby a screw-in object member is pierced at the edges of the V-shaped grooves 16. |
