| 摘要 |
Provided in the present invention are a bolt and a nut, which comprise: a bolt where a right spiral unit and a left spiral unit having a smaller diameter than the right spiral unit are continuously formed on a spiral unit in an axial direction; a right screw nut which is fastened to the right spiral unit; a left screw nut which is fastened to the left spiral unit; and a middle washer which circumscribes to the right spiral unit of the bolt and is included into between the right screw nut and the left screw nut in order to be combined with the outer circumferential surfaces of the right and left screw nuts in a male-female fastening method. Therefore, the fastening bolt and nut can be fastened by preventing a bolt and a nut combined with an object to be combined from rotating in a loosening direction, can prevent the axial direction movement of the right and left screw nuts even during the occurrence of repetitive vibration in the axial direction of the bolt by including the middle washer between the right and left screw nuts, and can easily loosen the nut from the spiral unit of the bolt with intention by selectively releasing the combining state between a middle screw and the left screw nut. |
