| 摘要 |
PROBLEM TO BE SOLVED: To neatly store a self-boring screw for attaching an exterior member coated with a paint film without damaging a surface film, and to smoothly perform the following puttying. SOLUTION: The screw having a countersunk head part with a cross-shaped hole to which a driver bit is fitted, a shaft part on which a male screw is arranged and a pointed tip end, is provided with a first screw part in which a single-start thread is formed on the peripheral surface of the shaft part from the lower of the head part to the middle of the shaft part and a second screw part in which a double-start thread is formed which comprises a higher screw thread formed to have a larger outside diameter than that of the single-start thread from the terminal part of the first screw part toward the tip part and a lower screw thread formed to have a smaller outside diameter than that of the single-start thread of the first screw part. The second screw part is so formed that its screw thread is gradually lowered in the vicinity of the tip part toward the tip part, so that the screw can be neatly stored by pushing the surface film of the exterior member in the inside of the exterior member, and post-treatment such as puttying can be smoothly performed.
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