| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a screw which is used for mounting various members, and which cannot be loosened easily by a third person with a predetermined tool after the screw is screwed into a predetermined position by providing a folded engagement groove without having regularity on a head of the screw. <P>SOLUTION: In the screw including the head and a shaft integrally formed with the head and having a male screw on the circumference, the engagement groove which is folded without having regularity is formed in the head of the screw. The engagement groove is formed combining a plurality of elliptical grooves. <P>COPYRIGHT: (C)2012,JPO&INPIT |
