JP3489762B2 - Nut retaining bolt - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bolt provided with a mechanism for preventing a nut from being screwed out. 2. Description of the Related Art A conventional nut retaining bolt is provided with a pin hole penetrating in the radial direction at a position near the tip of a shaft portion. After the nut is screwed, a split pin is inserted into the pin hole. The nut is prevented from coming off by penetrating and locking the nut. [0003] In the above-mentioned conventional bolt, after engaging a nut at a work site, fine work for locking such as insertion of a split pin and bending of the tip of the split pin is performed. And the workability is poor. Therefore, the present invention
It is an object of the present invention to provide a nut retaining bolt that can prevent the nut from coming off without performing other detailed operations such as mounting a split pin by merely screwing the nut. In the present invention, in order to solve the above-mentioned problems, a bolt 1 is constituted by a bolt main body 2 and a retaining pin 3 attached thereto. At the position near the tip of the shaft portion 4 of the bolt body 2, a horizontal hole 5 is formed penetrating in the radial direction, and a vertical groove 6 is formed in the axial direction from the opening of the horizontal hole 5 to the tip of the shaft portion 4. . The retaining pin 3 is provided with a pair of insertion pieces 7 whose tips are opposed to each other, and a pair of spring pieces 8 which are continuous with the insertion piece 7 and are connected to each other. The insertion piece 7 is inserted into the lateral hole 5 of the bolt shaft 4 so as to be able to advance and retreat in the radial direction. The spring pieces 8 bend from the base end of the insertion piece 7 respectively, and move toward each other toward the tip of the bolt shaft 4.
And extends along the vertical groove 6 so as to converge to a dimension equal to or smaller than the diameter of the bolt shaft 4 and is connected at the tip end side of the bolt shaft portion 4. In a normal state, the base of the insertion piece 7 protrudes outward from the outer periphery of the bolt shaft 4 to prevent the nut 11 screwed to the bolt shaft 4 from coming off. When the nut 11 is screwed, the spring piece 8 is elastically bent in accordance with the screw advance and falls down in the vertical groove 6, so that screwing is not hindered. Nut 11 is inserted piece 7
After passing through, the spring piece 8 is elastically restored to the normal state, and the nut 11 is prevented from coming off. Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of a bolt after mounting a nut,
FIG. 2 is a sectional view of a part of the bolt in the process of mounting the nut. [0006] In the drawing, the nut retaining bolt 1 is
It has a bolt body 2 and a retaining pin 3 attached to the bolt body 2. A lateral hole 5 is formed in the bolt body 2 near the tip of the shaft portion 4 so as to penetrate in the radial direction. This side hole 5
The longitudinal grooves 6 are formed so as to extend in the axial direction from the opening of each of the shaft portions 4 to the tip of the shaft portion 4. The retaining pin 3 is formed by bending an elastic metal wire, and has a pair of insertion pieces 7 having opposite ends.
And a pair of spring pieces 8 which are bent and connected to each other. The insertion piece 7 is inserted into the lateral hole 5 of the bolt shaft 4 so as to be able to advance and retreat in the radial direction. The spring piece 8 is the insertion piece 7
So that they converge toward the distal end of the bolt shaft portion 4 to have a dimension equal to or less than the diameter of the bolt shaft portion.
It extends along the vertical groove 6 and is connected in a loop at the tip end side of the bolt shaft 4. The spring pieces 8 may be connected in a U-shape. In a normal state, the base of the insertion piece 7 is
Projecting outward from the outer periphery of the nut 11 to prevent the nut 11 screwed to the bolt shaft 4 from coming off. When the nut 11 is screwed, the spring piece 8 is elastically bent according to the screw advance and falls down in the vertical groove 6. Therefore, the screwing of the nut 11 is not hindered. After the nut 11 has passed through the insertion piece 7, the spring piece 8 is elastically restored to the normal state and the insertion piece 7 projects,
The nut 11 is prevented from coming off. The bolt body 2 is brought to the work site with the retaining pin 3 attached thereto in advance, and is attached to a required position, and the nut 1 is attached.
1 is screwed. At the work site, there is no need to perform any special slippage prevention operation other than the work of tightening the nut 11. As described above, in the present invention, the bolt 1 is constituted by the bolt body 2 and the retaining pin 3 attached thereto, and the tip of the shaft portion 4 of the bolt body 2 is closer to the tip. At a position, a horizontal hole 5 is formed penetrating in the radial direction, and a vertical groove 6 is formed in the axial direction from the opening of the horizontal hole 5 to the tip of the shaft portion 4. And a pair of spring pieces 8 continuous with the insertion piece 7 and connected to each other.
The insertion piece 7 is inserted into the lateral hole 5 of the bolt shaft part 4 so as to be able to advance and retreat in the radial direction. The spring pieces 8 are bent from the base end of the insertion piece 7 respectively, and It extends along the vertical groove 6 so that it converges to a dimension equal to or smaller than the diameter of the bolt shaft portion 4 toward the front end, and is connected at the front end side of the bolt shaft portion 4. In a normal state, the base of the insertion piece 7 is The nut 11 protrudes outward from the outer periphery of the bolt shaft 4 and prevents the nut 11 screwed to the bolt shaft 4 from coming off.
When the nut 11 passes through the insertion piece 7, the spring piece 8 is elastically bent in accordance with the screw advance so as to fall down into the vertical groove 6 so as not to hinder the screwing. 8 is restored to its normal state by elasticity, and the nut 11 is prevented from coming out. Therefore, the bolt body 2 is brought to the work site in a state where the retaining pin 3 is mounted in advance, and the nut 11 is screwed into the required position. By simply doing so, the nut can be prevented from coming off without performing a special slippage prevention operation such as insertion of the split pin or bending of the tip of the split pin. This has the effect of simplifying work on site and improving work efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of a bolt after mounting a nut. FIG. 2 is a sectional view of a part of a bolt in the process of mounting a nut. [Description of Signs] 1 bolt 2 bolt body 3 retaining pin 4 shaft 5 lateral hole 6 vertical groove 7 insertion piece 8 spring piece 11 nut

Claims (1)

(57) [Claims 1] A lateral hole formed penetrating in the radial direction near the tip of the bolt shaft portion, and an axial direction extending from the opening of the lateral hole to the tip of the bolt shaft portion. A bolt body having a longitudinal groove formed in the bolt hole; a pair of insertion pieces which are inserted into the lateral hole so as to be able to advance and retreat in the radial direction with respect to the bolt shaft portion, and whose tips are opposed to each other; Bent from the base end, extend along the vertical groove of the bolt shaft portion so as to converge toward the distal end of the bolt shaft portion with a dimension equal to or less than the diameter of the bolt shaft portion, and are connected at the distal end side of the bolt shaft portion. In the normal state, the base of the insertion piece protrudes outward from the outer periphery of the bolt shaft to prevent the nut screwed to the bolt shaft from coming out, but when the nut is screwed, The spring piece is made to approach against the elasticity according to the screw advance, and the vertical A retaining pin which does not hinder the screwing by falling down in the groove and which is restored to a normal state by elastic force after passing through the nut to prevent the nut from coming off. .