USE OF A GUIDE PORTION ON A BOLT

摘要

In a bolt of the present invention, a guide portion (116) having a small diameter is formed at the distal end of a shaft portion (15) and ridge (31) having an inverted direction screw configuration relative to the ridge (30) formed on a constant diameter portion (115) is formed. When the bolt (1) is inserted obliquely into a nut (100) and the ridge (31) gets into engagement with a female screw portion (105) of the nut (100), an effect of floating the bolt (1) is generated, and the bolt 1 cannot be driven into the nut 100 unless it is set in an appropriate tightening posture. Consequently, biting and seizing of the bolt 1 to the nut 100 can be prevented securely. If the ridge (31) is formed into a double threaded screw having an inverted direction screw configuration, the effect can be further intensified.