METHOD AND STRUCTURE FOR PREVENTING SCREW FROM LOOSENING AND METHOD OF MANUFACTURING MALE SCREW

摘要

Prior to engaging a male screw (18A) formed on the outer circumference of a second member (18) with a female screw (15A) formed on the inner circumference of a hole (15) in a first member (5), protruding parts (40) which protrude outward in the radial direction and are positioned at one end side of the male screw (18A) in the axial direction are formed in a plurality of regions which are separated from each other in the circumferential direction on the outer circumference of the second member (18) on which the male screw (18A) is formed. The male screw (18A) is then engaged with the female screw (15A) from the other end side of the male screw (18A) in the axial direction. The torque required to rotate the male screw (18A) engaged with the female screw (15A) in the loosening direction is set so as to be greater in a state where the protruding parts are interposed between the male screw (18A) and the female screw (15A) than in a state where the protruding parts are not so interposed.