JPH11294429A - Strong coupling bolt and nut - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent uncoupling of a bolt and nut by intentionally exerting an excessive force. SOLUTION: An axially extending wedge groove 14 is formed in the male screw part 13 of a bolt 10 or the female screw part 21 of a nut 20. A wedge body 30 is driven in the wedge groove with the female screw part of the nut threadedly engaged with the male screw part of the bolt. The nut female screw part and the bolt male screw part are forced into strong pressure-bonding with each other on the opposite side to the wedge groove, and by crushing the female screw of the nut or the male screw of the bolt, the bolt and the nut are strongly intercoupled in a non-removable state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bolt and a nut which can be strongly coupled, and more particularly to a bolt and a nut which, once fastened, are irremovably coupled to each other.

[0002]

2. Description of the Related Art When two or more workpieces are fastened,
Bolts and nuts are often used. Normally, in such a bolt / nut, a bolt shaft portion is inserted into an insertion hole of a member to be fastened, a female screw of the nut is screwed into a male screw of the bolt, and a plurality of members to be tightened are tightened between the bolt head and the nut. The method of fastening is common.

By the way, in this kind of bolt / nut, there is a possibility that the fastening may be loosened due to vibration, thermal expansion, aging, etc., and therefore various methods for preventing loosening have been proposed. For example, a method using a bending washer or a lock wire,
There are known a method of penetrating a split pin through a nut and a bolt, a method of using a double nut (JP-A-6-26512, etc.), and a method of using a bolt having a self-locking screw (JP-A-7-42724, etc.). Have been.

[0004]

However, in the conventional methods for preventing loosening, it is assumed that the bolts and nuts are reused and the loosening is simply prevented, so that the bolts or nuts are intentionally excessively large. When the bolt or the nut is turned by force, the bolt or the nut turns in a loosening direction, and there has been a problem that the fastening of the member to be fastened can be released.

In order to prevent this, it is necessary to fix the bolt screw portion and the nut by welding or the like, but the operation is very complicated.

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to provide a bolt and a nut in which a member to be fastened cannot be disengaged even if an excessive force is intentionally applied.

[0007]

SUMMARY OF THE INVENTION Accordingly, a bolt according to the present invention is a bolt for fastening at least two members to be fastened between a bolt head and a nut. Wedge grooves are formed extending in the axial direction over the range in which the wedge grooves are formed, and further include a wedge body that fits into the wedge grooves and can interfere with the female screw of the nut. The wedge body is driven between the male screw part of the bolt and the female screw part of the nut in the wedge groove in a state in which the female screw part of the wedge groove and the female screw part of the nut on the opposite side of the wedge groove are mutually engaged. It is characterized in that the female screw of the nut is crushed and the female screw of the nut is crushed, and the nut is firmly irremovably connected to the nut.

One of the features of the present invention is that a wedge groove extending in the axial direction is formed in the male screw portion of the bolt, and a wedge is driven into the wedge groove in a state where the female screw portion of the nut is screwed into the male screw portion of the bolt.
The male screw portion of the bolt and the female screw portion of the nut on the opposite side of the wedge groove are strongly press-fitted to each other, the female screw of the nut is crushed, and the bolt and the nut are detachably and strongly connected. As a result, the bolt and the nut are integrated, and if the bolt or the nut is intentionally loosened with an excessive force, the bolt or the nut is not loosened, and the fastening is not released unless the bolt or the nut is broken.

Since the wedge member is driven between the male screw portion and the female screw portion of the nut, the wedge groove may be formed at least over a range where the nut of the male screw portion is located at the time of fastening. The shape of the wedge body is not particularly limited as long as the wedge body can be driven into a wedge groove between the bolt male screw part and the nut female screw part. For example, the entire wedge may be L-shaped, and the wedge may be inserted into a wedge groove formed in a part of the bolt external thread portion in the axial direction. Therefore, a wedge groove is formed so as to be opened in the bolt screw portion tip surface or the bolt head top surface, and the wedge body is driven into the wedge groove from the opening end of the bolt screw portion tip surface or the bolt head top surface. Is good.

Further, a wedge groove is formed in the male screw part of the bolt to crush the female screw of the nut. Conversely, a wedge groove is formed in the female screw part of the nut to crush the male screw of the nut, but the fastening is similarly released. Can be reliably prevented.

That is, a nut according to the present invention is a nut for fastening at least two members to be fastened between the nut and a bolt head, wherein a wedge groove extends in the axial direction in a female screw portion on an inner peripheral surface of the nut. The wedge groove further includes a wedge body which is formed to be open at one end face in the axial direction and which can fit into the wedge groove and interfere with the male screw of the bolt, wherein the male screw part of the bolt and the female screw part of the nut are screwed. When the wedge body is driven into the wedge groove from the open end of the wedge groove in the fitted state, the bolt external thread portion and the nut female thread portion on the opposite side of the wedge groove are strongly crimped to each other, and the bolt is tightened. Is crushed so as to be irremovably firmly connected to the bolt.

The wedge groove may be formed so as to be open at least at one end face in the axial direction. The wedge body is driven into the bolt male screw part and the nut female screw part on the opposite side of the wedge groove, and a bolt male screw is formed. In consideration of the operation of crushing the wedge, it is preferable that the wedge groove is formed by opening both end surfaces in the axial direction so that the wedge body can be sufficiently driven.

The wedge body has an important function of crushing the male screw of the bolt or the female screw of the nut by driving into the wedge groove. Accordingly, the wedge body may be made of a material having the same hardness as the bolt or the nut, but it is preferable to use a harder material from the viewpoint of more securely crushing the screw.

The cross-sectional shape of the wedge body is not particularly limited as long as the screw can be sufficiently crushed. For example, a rectangular cross-sectional shape, a triangular cross-sectional shape, a semicircular cross-sectional shape, a circular cross-sectional shape, and the like can be employed. . Further, the shape of the wedge groove may be any shape as long as the wedge body can be accommodated so as to interfere with the female nut or the male screw of the nut.

[0015]

According to the present invention, a wedge groove extending in the axial direction is formed in the male screw portion of the bolt or the female screw portion of the nut, and the wedge is formed with the female screw portion of the nut screwed into the male screw portion of the bolt. A wedge is driven into the groove, and the male screw part of the bolt and the female screw part of the nut on the opposite side of the wedge groove are mutually strongly press-bonded. Even if the bolt or the nut is intentionally loosened with an excessive force, the bolt and the nut are not integrated and loosened. Therefore,
Unless the bolt or the nut is broken, the fastening does not come off and the reliability of the fastening can be greatly improved.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to specific examples shown in the accompanying drawings. 1 to 3 show a preferred embodiment of a bolt capable of being strongly coupled according to the present invention. In the figure, a bolt 10 capable of strong connection has a wedge body 30. In the bolt 10, a hexagonal head 12 is formed at one end of a shaft 11, and a male screw 13 is formed by engraving a male screw from the center of the shaft 11 to the other end.

A wedge groove 14 having a substantially rectangular cross section is formed in the male screw portion 13 of the bolt 10 so as to extend in the axial direction. On the other hand, the wedge body 30 fits into the wedge groove 14 and
0 has a rectangular cross section that can sufficiently interfere with the male screw portion 13, and its tip is cut into a tapered shape to form an acute angle, and is manufactured using a material harder than the bolt 10 and the nut 20. Have been.

When a plurality of members W1 and W2 are to be fastened, the male screw 13 of the bolt 10 is inserted into the insertion hole of the members W1 and W2 via the washer 40, and the male screw 1
3 is provided with a female thread 21 of the nut 20 via a washer 40.
And the two fastened members W1 and W2 are fastened between the head 12 of the bolt 10 and the nut 20. The washer 40 may not be used in some cases.

Thereafter, the distal end side of the wedge member 30 is inserted into a wedge groove 14 formed in the male screw portion 13 of the bolt 10.
When the wedge body 30 is inserted from the open end side, the front end side of the wedge body 30 interferes with the female screw portion 21 of the nut 20. When it becomes difficult to insert the wedge body 30 further, the rear end side of the wedge body 30 is hit with a hammer or the like, 30 is completely driven into the wedge groove 14.

Then, as shown in FIG.
The center axis of the nut 20 and the bolt 10 is displaced by the driving, and the female thread portion 21 of the nut 20 and the bolt 10
The male thread 13 of the nut is strongly pressed against each other, the thread of the female thread of the nut 20 is crushed, the nut 20 and the bolt 10 are completely integrated, and the nut 20 cannot be rotated with respect to the bolt 10. If the bolt 10 or the nut 20 is intentionally loosened with an excessive force, it will not be loosened.

Therefore, the members to be fastened W1 and W2 are held in a completely tightened state, and the head 1 of the bolt 10
2, the bolt 10 and the nut 20 cannot be disengaged unless the male thread portion 13 is broken above the nut 20 or the nut 20 itself is broken. Can be improved.

FIGS. 4 to 6 show a second embodiment.
In the drawings, the same reference numerals as those in FIGS. 1 to 3 indicate the same or corresponding parts. In this example, a semicircular wedge groove 22 is formed in the female screw portion 21 of the nut 20 over the entire length in the axial direction and is opened at both end surfaces of the nut 20, while the wedge body 30 has a cylindrical tip portion tapered. It is cut into an acute angle.

When the members W1 and W2 are fastened, the female member 21 of the nut 20 is screwed into the male thread 13 of the bolt 10 in the same manner as in the above embodiment, and the members W1 and W2 are fastened.
After tightening, the wedge body 3 is inserted into the wedge groove 22 of the nut 20 this time.
0 and the wedge body 30 is completely driven into the wedge groove 22, as shown in FIG.
And the male screw portion 13 of the bolt 10 are strongly pressed together, the male screw of the bolt 10 is crushed, and the bolt 10 and the nut 20 can be completely integrated.

[Brief description of the drawings]

FIG. 1 is a view showing a front surface (a) and a bottom surface (b) of a preferred embodiment of a bolt capable of strong connection according to the present invention.

FIG. 2 is a view showing a side surface (a) and a back surface (b) of a wedge used in the embodiment.

FIG. 3 is a diagram showing a fastening state using the bolt.

FIG. 4 shows a front view (a) and a cross-section (b) of a preferred embodiment of a nut capable of strong connection according to the present invention.

FIG. 5 is a diagram showing a side surface (a) and a back surface (b) of a wedge used in the embodiment.

FIG. 6 is a diagram showing a fastening state using the nut.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Bolt 11 Shaft part 12 Head 13 Male screw part 14 Wedge groove 20 Nut 21 Female screw part 22 Wedge groove 30 Wedge body W1, W2 Fastened member

Claims (4)

[Claims] 1. A bolt for tightening by tightening at least two members to be fastened between a bolt head and a nut, wherein a wedge groove extends in an axial direction at least in a range where the nut is located at the time of fastening in a bolt external thread portion. The wedge body further includes a wedge body that can fit into the wedge groove and interfere with the female screw of the nut, and the wedge body is screwed with the female screw part of the nut and the female screw part of the nut. By being driven between the bolt male screw part and the nut female screw part in the groove, the bolt male screw part and the nut female screw part on the opposite side of the wedge groove are mutually strongly press-fitted and the female screw of the nut is crushed, A bolt characterized in that it is irremovably firmly connected to the nut. 2. The wedge groove is formed so as to open to the tip surface of the bolt screw portion or the top surface of the bolt head, and the wedge body is formed from the opening end of the tip surface of the bolt screw portion or the top surface of the bolt head. 2. The bolt according to claim 1, wherein the bolt is driven into the wedge groove. 3. A nut for fastening at least two members to be fastened between a bolt head and a bolt head, wherein a wedge groove extends in an axial direction in a female screw portion of an inner peripheral surface and is provided on at least one end surface in the axial direction. A wedge body that is formed to be open and that can fit into the wedge groove and interfere with the male screw of the bolt, and the wedge body is screwed with the male screw part of the bolt and the female screw part of the nut; Is driven into the wedge groove from the open end of the wedge groove, so that the male screw part and the female screw part of the nut on the opposite side of the wedge groove are mutually strongly pressed and the male screw of the bolt is crushed, and A nut characterized in that it is irremovably firmly connected to the nut. 4. The nut according to claim 3, wherein the wedge groove is formed so as to open at both end faces in the axial direction.