JPH0968210A - Nut-locking bolt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nut-locking bolt which is put into nut-locking action in a working site simply by nut fitting work without other minute operations. SOLUTION: This locking bolt 1 comprises a bolt main body 2 and a lock pin 3. A lateral hole 5 is formed in the shank 4 of the bolt main body 2, and a longitudinal groove 6 is formed from an opening at each end of the lateral hole 5 to the end of the shank 4. The lock pin 3 has a pair of insertion pieces 7 and a pair of spring pieces 8 continued to the pieces 7 and joined to each other. The insertion pieces 7 are inserted into the lateral hole 5 in such a way as to freely move back and forth. The spring pieces 8 are extended along the longitudinal groove 6 and joined together so as to be reduced to a size not more than the diameter of the bolt shank 4. The ends of the insertion pieces 7 are normally projected from the outer periphery of the bolt shank 4 to prevent a nut 11 from being unlocked. In fitting the nut 11 around the bolt, the spring pieces 8 are elastically deflected and retained in a horizontal position inside the vertical groove 6 to avoid interference with fitting of the nut around the bolt, After the nut 11 has passed through, the spring pieces 8 are restored to automatically lock the nut into place.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bolt having a mechanism for preventing a screwed nut from coming out.

[0002]

2. Description of the Related Art A conventional nut retaining bolt is provided with a pin hole that penetrates in the radial direction at a position near the tip of a shaft. After the nut is screwed, a split pin is inserted into the pin hole. It is a type that prevents the nut from slipping out by locking the nut.

[0003]

In the conventional bolts described above, after the nuts are screwed together at the work site, detailed work for inserting the split pins and bending the tip of the split pins must be performed. However, there is a problem that workability is poor. Therefore, the present invention is
An object of the present invention is to provide a nut retaining bolt capable of preventing the nut from coming off only by screwing the nut without performing other detailed work such as mounting the split pin.

[0004]

In the present invention, in order to solve the above-mentioned problems, a retaining bolt 1 is constituted by a bolt body 2 and a retaining pin 3 attached thereto. A lateral hole 5 is formed at a position near the tip of the shaft portion 4 of the bolt body 2 so as to penetrate in the radial direction, and a vertical groove 6 is formed in the axial direction from the opening of the lateral hole 5 to the tip of the shaft portion 4, respectively. . 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 pieces 7 and are connected to each other. The insertion piece 7 is inserted into the lateral hole 5 of the bolt shaft portion 4 so as to be able to advance and retract in the radial direction. The spring pieces 8 are respectively bent from the base end of the insertion piece 7 and are directed toward the tip of the bolt shank 4 with respect to each other.
The bolt shaft portion 4 extends along the vertical groove 6 so as to converge to a dimension equal to or smaller than the diameter, and is connected to the tip end side of the bolt shaft portion 4. In the normal state, the base portion of the insertion piece 7 projects outward from the outer periphery of the bolt shaft portion 4 and prevents the nut 11 screwed into the bolt shaft portion 4 from coming off. When the nut 11 is screwed, the spring piece 8 is elastically bent in accordance with the screw advancement, and the spring piece 8 is laid down in the vertical groove 6 so that the screwing is not hindered. The nut 11 is the insertion piece 7
After passing through, the spring piece 8 is elastically restored to the normal state, and the nut 11 is prevented from coming out.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. Figure 1 is a cross-sectional view of the bolt after mounting the nut,
FIG. 2 is a cross-sectional view of a part of the bolt in the process of mounting the nut.

In the figure, the nut retaining bolt 1 is
The bolt body 2 and the retaining pin 3 attached to the bolt body 2 are provided.

A lateral hole 5 is formed near the tip of the shaft portion 4 of the bolt body 2 so as to penetrate therethrough in the radial direction. This side hole 5
Vertical grooves 6 are formed so as to extend in the axial direction from the respective openings 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 whose tips are opposed to each other, and the insertion piece 7.
And a pair of spring pieces 8 that are connected to each other by being bent and connected to each other. The insertion piece 7 is inserted into the lateral hole 5 of the bolt shaft portion 4 so as to be able to advance and retract in the radial direction. The spring piece 8 is the insertion piece 7
So that they are bent from the base end of each of them and converge toward each other toward the tip of the bolt shank 4 to a dimension not larger than the diameter of the bolt shank,
It extends along the vertical groove 6 and is connected in a loop shape at the tip end side of the bolt shaft portion 4. The spring pieces 8 may be connected in a U shape. In the normal state, the base of the insertion piece 7 is the bolt shaft 4
The nut 11 that protrudes outward from the outer periphery of the nut and is screwed into the bolt shaft portion 4 is prevented from coming out. When the nut 11 is screwed, the spring piece 8 is elastically bent in accordance with the screw advancement and is laid down in the vertical groove 6. Therefore, the screwing of the nut 11 is not hindered. After the nut 11 passes through the insertion piece 7, the spring piece 8 is elastically restored to the normal state, and the insertion piece 7 projects.
Prevent the nut 11 from coming off.

Bring the bolt pin 2 to the work site with the retaining pin 3 attached in advance, and attach it at the required position to install the nut 1
Screw 1 together. At the work site, it is not necessary to perform a special slip-out prevention operation other than the tightening work of the nut 11.

[0010]

As described above, in the present invention, the bolt body 2 and the retaining pin 3 attached to the bolt body 2 constitute the retaining bolt 1, and the bolt body 2 is located at a position near the tip of the shaft portion 4. , A horizontal hole 5 is formed penetrating in the radial direction, and vertical grooves 6 are formed in the axial direction from the opening of the horizontal hole 5 to the tip of the shaft portion 4, respectively, and the tip of the retaining pin 3 is opposed to each other. A pair of insertion pieces 7 and a pair of spring pieces 8 continuous with the insertion pieces 7 and connected to each other
And the insertion piece 7 is inserted into the lateral hole 5 of the bolt shaft portion 4 so as to be able to move forward and backward in the radial direction, and the spring pieces 8 are bent from the base end of the insertion piece 7, respectively, and the insertion pieces 7 of the bolt shaft portion 4 are mutually bent. It extends along the vertical groove 6 so as to converge toward the tip to a dimension equal to or smaller than the diameter of the bolt shank 4 and is connected at the tip side of the bolt shank 4, and in the normal state, the base of the insertion piece 7 is The nut 11 protruding outward from the outer periphery of the bolt shaft portion 4 is prevented from coming out of the nut 11 screwed into the bolt shaft portion 4,
When the screw is engaged, the spring piece 8 is elastically bent in accordance with the screw advancement so that the spring piece 8 is laid down in the vertical groove 6 so that the screwing is not hindered. Since 8 is elastically restored to the normal state to prevent the nut 11 from coming off, bring the bolt body 2 to the work site with the retaining pin 3 attached in advance, attach it to the required position and screw the nut 11 into place. By simply doing so, it is possible to prevent the nut from coming off without performing a special coming-out preventing operation such as inserting the cotter pin or bending the tip of the cotter pin. This has the effect that the work at the site is easy and the work efficiency is improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a bolt after mounting a nut.

FIG. 2 is a cross-sectional view of a part of a bolt in the process of mounting a nut.

[Explanation of symbols]

 1 Bolt 2 Bolt body 3 Locking pin 4 Shaft 5 Horizontal hole 6 Vertical groove 7 Insert piece 8 Spring piece 11 Nut

Claims (1)

[Claims] 1. A bolt shaft portion is provided with a lateral hole formed near the tip thereof in a radial direction, and vertical grooves formed axially from the opening of the lateral hole to the tip of the bolt shaft portion. A bolt body, a pair of insert pieces inserted into the lateral hole so as to be able to advance and retreat in the radial direction with respect to the bolt shank, and the tips of the insert pieces facing each other, and the base pieces of the insert pieces are respectively bent to form bolts. A pair of spring pieces that extend along the vertical groove of the bolt shaft portion and that are connected to each other at the tip end side of the bolt shaft portion so as to converge toward the tip of the shaft portion to a dimension not greater than the diameter of the bolt shaft portion. In the normal state, the base of the insertion piece projects outward from the outer periphery of the bolt shaft to prevent the nut screwed on the bolt shaft from coming out, but when the nut is screwed, the spring piece is elastically resisted as the screw advances. And bring them closer to each other to lie down in the vertical groove of the bolt shaft. Thus not disturb the screwing and retaining bolt of the nut, characterized in that after passage of the nut comprises a retaining pin to prevent coming off of the nut to restore to normal the elastic force.