JP2000205225A - Bolt and nut having sloped outer control surface and method of tightening/releasing thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide mass-producible bolts and nuts of a simple structure, having a sloped outer contour surface difficult in tightening/releasing with a general tightening tool, particularly in releasing, and a method of tightening/ releasing thereof. SOLUTION: An outer contour surface of a nut 1 is formed with a sloped surface 2 spread from top toward downward. In this way, the nut can not be surely tightened/released without using an exclusive tightening tool coming into surface contact with this sloped surface 2. A tightening tool of general spanner or the like comes into line contact with an outer contour of the nut 1, accordingly particularly making releasing difficult. In this way, mischief and theft by a general person are surely prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a head and a nut of a bolt, and more particularly to a bolt and a nut having an inclined outer contour surface having an inclined outer contour surface, and methods for fastening and releasing the bolt and nut.

[0002]

2. Description of the Related Art A head portion and a nut of a bolt have a peripheral surface having a hexagonal outer contour, for example, and each peripheral surface is vertically formed vertically. That is, most of the peripheral side surfaces are formed at right angles to the bottom surface. Some of them have an inclined surface on a part of the peripheral side surface, but this is only an inclined surface for chamfering, and there is no one entirely composed of an inclined surface.

[0003]

The conventional heads and nuts of the conventional bolts have vertical peripheral surfaces solely for the convenience of fastening and release and the ease of manufacture. That is, when fastening or loosening bolts and nuts, fastening tools such as spanners, box spanners, torque wrenches, etc. are used, but all of these are vertical members that fit into the outer contours of the bolt head and nut. It has a mating surface. On the other hand, when these fastening tools have an engagement surface shaped so as not to fit into the head portion or nut of the bolt, reliable fastening is impossible or a very long time is required for fastening. Occurs.

[0004] Although bolts and nuts need to be securely fastened, there are cases where the fastening cannot be easily released. Generally, it is necessary that fastening and release can be performed reliably and easily. However, it is often desirable that ordinary people cannot easily release the fastening once it has been fastened. That is,
For example, in the case of a railway rail or a public facility, an inexperienced person may play a trick if the fastening can be easily released. In addition, theft accidents are likely to occur. Of course, no matter what the structure of the bolts and nuts is, if a special dedicated fastening tool corresponding to this is used, it is difficult to completely prevent the release of the fastening. However, it is rare for ordinary people to easily obtain dedicated fastening tools and to always prepare them. Further, if a bolt or nut having a complicated shape or a fixing agent is used in order to prevent the release of the fastening, it becomes expensive and lacks universality. Therefore, there is a demand for bolts and nuts which have a simple structure, but which can be securely fastened and whose fastening is generally difficult to release. In addition, bolts and nuts are used in large quantities and need to be easily manufactured.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned demands, and it is difficult to reliably perform the fastening with a general fastening tool such as a wrench, and it is more difficult to release the fastening, and it is relatively easy. It is an object of the present invention to provide bolts and nuts having a simple structure which can be manufactured in a simple manner, and methods for fastening and releasing the bolts and nuts.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a bolt head and a nut having a polygonal or arbitrary non-circular outer contour, comprising a surface of the outer contour. Are bolts and nuts having a slanted outer contour surface composed of a slant surface which spreads from the upper side to the lower side. Further, a bolt head and a nut having a polygonal or arbitrary non-circular outer contour of a bolt and a nut, wherein the outer contour surface is inclined from the upper surface to the lower surface so as to be inclined. A method for fastening and unfastening an object, wherein a dedicated fastening tool having a concave portion having an inner contour shape fitted into the outer contour of the head portion and the nut of the bolt is put on the head portion and the nut of the bolt, and It is characterized by a method of fastening and releasing bolts and nuts having an inclined outer contour surface for rotating a fastening tool. A bolt head and a nut having a polygonal or arbitrary non-circular outer contour, wherein a bottom surface of the bolt or nut is formed by an inclined surface in which the surface of the outer contour spreads downward from above and inclines. A fastening method for tightening the fastening object by directly contacting or directly contacting the surface of the fastening object with a washer, wherein the head portion of the bolt and the bottom surface of the nut are fixed to the surface of the washer when fastening. It is arranged at least below the surface of the fastening object. Also,
The washer has a larger area than the bottom surface of the head portion and the nut of the bolt, and is formed of a shape that curves upward in an arc, or the washer or the head portion of the bolt and the nut of the object to be fastened. A concave hole into which the bottom surface fits is formed on the contact surface of the bottom surface.

[0007] The outer contour surfaces of the head portion of the bolt and the nut are inclined surfaces. Therefore, in a general fastening tool, the head portion of the bolt and the outer contour of the nut are in line contact with each other, and the fastening tool cannot be slipped and sufficiently fastened. Further, since the release of the fastening generally requires a larger force than the fastening, the bolt and the nut of the present invention cannot be loosened by a general fastening tool such as a spanner. On the other hand, since header processing has been developed in recent manufacturing techniques, bolts and nuts having inclined surfaces can be manufactured relatively easily and in large quantities.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a bolt and a nut having an inclined outer contour according to an embodiment of the present invention; Since the head portion of the bolt and the nut have substantially the same shape, the following description will mainly focus on the nut. The nut 1 according to the present invention shown in FIGS. 1 to 3 is of a general shape having a hexagonal outer contour in the present embodiment. All the peripheral side surfaces of this outer contour are formed of inclined surfaces 2 having an angle θ as shown in FIG. The inclined surface 2 extends from the upper surface 3 of the nut 1 toward the bottom surface 4 and is inclined. Although the angle θ may be arbitrary, for example, about 20 ° to about 60 ° is appropriate.
In the center of the nut 1, a screw hole 5 having a size corresponding to the outer contour of the nut 1 is threaded. Further, the nut having the above structure can be easily press-formed from a round material by header processing.

FIG. 4 shows a state in which the nut 1 of the present invention is fastened or unfastened by a spanner 6 which is one of general fastening tools. The spanner 6 includes a hole 7 and a handle 8. The hole 7 is generally a hexagonal hole having a vertical inner wall 9.
Therefore, when the wrench 6 is engaged with the nut 1, the inner wall 9 abuts on the inclined surface 2 of the nut 1 only at its lower end, and comes into a line contact state. Therefore, even if the wrench 6 is tightened in this state, a sufficient tightening force is not transmitted to the nut 1, resulting in insufficient tightening. On the other hand, when the nut 1 is sufficiently fastened by any means, the nut 1 is tightened.
It is probably impossible to try to relax with. As described above, the release of the fastening caused by mischief or the like is reliably prevented.

FIG. 5 shows a dedicated fastening tool 10 for securely fastening the nut 1 of the present invention. The dedicated fastening tool 10 includes, for example, a head 12 that forms a concave portion 11 having an inner contour shape corresponding to the outer contour surface of the nut 1 that needs to be fastened, and an operation section 13 that rotates the head. An inclined wall 14 corresponding to the inclined surface 2 of the nut is formed in the recess 11. Fastening work,
The head 12 of the special fastening tool 10 is put on the nut 1 lightly screwed on the bolt or the stud 15, and the recess 11 is
To fit. As a result, the entire inclined wall 14 of the recess 11 comes into contact with the inclined surface 2 of the nut. That is, the surface contact is different from the line contact in FIG. Therefore, a sufficient fastening force is applied to the nut 1 by rotating the operation unit 13, and the bottom surface 4 of the nut 1 is pressed against the fastening target 16, and secure fastening is performed. On the other hand, in order to loosen the nut 1, it is sufficient to rotate the operation unit 13 in the reverse direction, and the fastening is easily released as in the case of a normal nut using a fastening tool such as a conventional spanner.

The use of the dedicated fastening tool 10 as described above enables the fastening and unfastening of the nut 1 of the present invention. However, as described above, the dedicated fastening tool 10 has You need something that matches its size. Therefore, it is a limited tool. Further, if the person holding the dedicated fastening tool 10 as shown in FIG. 5 releases the fastening of the nut 1, the person needs to prepare various kinds of dedicated fastening tools 10 in advance. Therefore, even if the single dedicated fastening tool 10 is prepared, the fastening release is not easily and arbitrarily performed. As described above, the release of the fastening by the ordinary person can be reliably prevented.

The nut 1 of the present invention may be fastened directly to the fastening object 16 as shown in FIG. 5, but is often fastened via a washer 17 as shown in FIG. In the present embodiment, a recess 18 is formed in the washer 17 on the upper surface side. The concave hole 18 has an area into which the bottom surface 4 side of the nut 1 fits, and the bottom surface 4 of the nut 1 contacts the bottom surface 19 of the concave hole 18. In addition, the depth of the concave hole 18 may be an appropriate depth, and for example, is preferably 2 to 3 m / m or more.

In general, when the nut 1 is to be fastened or released, it is desirable that the dedicated fastening tool 10 is inserted to the vicinity of the bottom surface 4 of the nut 1. That is, when the lower surface of the dedicated fastening tool 10 is at the same level position as the surface of the fastening object 16 or the washer 17, it is easy to perform secure fastening and fastening release. Therefore, as shown in FIG. 6, when the bottom surface 4 of the nut 1 comes to a position lower than the surface of the washer 17, it becomes more difficult to release the fastening of the nut 1. As described above, the effect of preventing the release of the fastening can be improved. In addition, in FIG.
7, when the washer 17 is not specified, as shown in FIG.
8a may be provided. Thereby, substantially the same effect as described above can be obtained.

The washer 17 shown in FIG. 6 is a flat plate. For example, as shown in FIG. 8, there is a washer 20 which is curved upward in a free state in an arc shape. As shown in FIG. 9, when the nut 1 is tightened, only the portion of the washer 20 that comes into contact with the bottom surface 4 of the nut 1 is in close contact with the surface of the fastening target 16 as shown in FIG. A) is located above the bottom surface 4 of the nut 1 by a height h. Thereby, substantially the same effects as described above can be obtained.

FIG. 10 shows a bolt 22 having a head portion 21 formed in the same manner as the nut 1 described above. This bolt 2
In the case of 2, the nut cannot be securely fastened or unfastened without the special dedicated fastening tool 10 like the nut 1 described above.

In the above description, the head portion 21 of the nut 1 or the bolt 22 has a hexagonal outer contour. However, FIG. 11 has a triangular outer contour, FIG. Are octagonal nuts 1a, 1b, 1
c. Of course, the shape of the outer contour is not limited to the above. FIG. 14 shows a nut 1d having an elliptical outer contour 23, and FIG.
2 shows a nut 1e having the following. These nuts 1d, 1e
In this case, substantially the same effects as described above can be obtained.

As described above, the materials of the nut 1 and the bolt 22 are not particularly limited. For example, in the case of the nut 1 and the bolt 22 made of a soft material, the nut 1 and the bolt 22 are formed by using a general fastening tool. And the bolt 22 side is easily deformed locally, so that the fastening release becomes more impossible. Therefore, it is preferable to use a relatively soft metal or soft material for tightening a place where disengagement is particularly hindered.

[0018]

According to the present invention, a bolt having an inclined outer contour surface according to the present invention,
According to the nut and the method of fastening and releasing the nut, it is relatively simple and mass production is possible, and it is difficult for ordinary people to fasten and release the fastening, especially the fastening is difficult to release, and accidents such as mischief and theft are greatly reduced. Effect.

[Brief description of the drawings]

FIG. 1 is a perspective view of a nut according to the present invention.

FIG. 2 is a top view of FIG. 1;

FIG. 3 is a side view of FIG. 2;

FIG. 4 is a sectional view showing a state in which the nut of the present invention is fastened or unfastened by a conventional fastening tool.

FIG. 5 is a sectional view for explaining a special fastening tool for fastening or unfastening a nut according to the present invention and a fastening and releasing method using the same.

FIG. 6 is a cross-sectional view for explaining a washer having a concave hole interposed between an object to be fastened and the nut of the present invention, and a method of fastening and unfastening the nut using the washer.

FIG. 7 is a cross-sectional view showing a concave hole formed on the surface of the object to be fastened when the nut is directly fastened to the object without using a washer.

FIG. 8 is a sectional view for explaining a method of fastening a nut when an arc-shaped washer is used.

FIG. 9 is a cross-sectional view for explaining a method of fastening a nut when an arc-shaped washer is used.

FIG. 10 is a front view showing a bolt provided with a head having inclined peripheral side surfaces according to the present invention.

FIG. 11 is a top view showing the nut of the present invention having a triangular outer contour.

FIG. 12 is a top view showing a nut of the present invention having a square outer contour.

FIG. 13 is a top view showing the nut of the present invention having an octagonal outer contour.

FIG. 14 is a perspective view showing a nut of the present invention having an elliptical outer contour.

FIG. 15 is a perspective view showing a nut of the present invention having an arbitrary non-circular outer contour.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Nut 1a Nut 1b Nut 1c Nut 1d Nut 1e Nut 2 Inclined surface 3 Top surface 4 Bottom 5 Screw hole 6 Spanner 7 Hole 8 Pattern portion 9 Inner wall 10 Dedicated fastening tool 11 Depression 12 Head 13 Operating portion 14 Inclined wall 15 Stud 16 Fastening Object 17 Washer 18 Concave hole 18a Concave hole 19 Bottom 19a Bottom 20 Washer 21 Head 22 Bolt 23 Elliptical outer contour 24 Non-circular outer contour

Claims (4)

[Claims] 1. A head part and a nut of a bolt having a polygonal or arbitrary non-circular outer contour, wherein said outer contour surface is formed of an inclined surface which spreads from upper to lower and inclines. Bolts having an inclined outer contour surface,
nut. 2. A bolt head and a nut having a polygonal or arbitrary non-circular outer contour, comprising a slanted surface in which the surface of the outer contour is inclined from the upper side to the lower side. And a dedicated fastening tool having an inner contour-shaped concave portion to be fitted into the outer contour of the nut and the head part of the bolt, and covers the head part and the nut of the bolt. A method for fastening and releasing bolts and nuts having an inclined outer contour surface, wherein the dedicated fastening tool is rotated. 3. A bolt head and a nut of a bolt having a polygonal or arbitrary non-circular outer contour, wherein the outer contour surface is inclined from the top to the bottom. The bottom surface of the bolt is fastened to the surface of the fastening object via a washer or directly, thereby tightening the fastening object, wherein the head portion of the bolt and the bottom surface of the nut are the washer at the time of fastening. A method for fastening a bolt and a nut having an inclined outer contour surface, wherein the bolt and the nut are disposed at least below the surface of the object or the surface of the object to be fastened. 4. The washer is formed of a shape having a larger area than the head portion of the bolt and the bottom surface of the nut and curved in an upwardly arcuate shape, or of the bolt of the washer or the object to be fastened. 4. The method according to claim 3, wherein a concave hole into which the bottom surface is fitted is formed in a contact surface of the bottom surface of the head portion and the nut.