JPH0914250A - Fastening method by covered nut - Google Patents

Abstract

PURPOSE: To provide a fastening method by a covered nut that can prevent a nut from being self-locked or left untightened or can prevent the scattering of a jacket member mounted on the nut. CONSTITUTION: In a covered nut A, a jacket member 2 mounted on the periphery of a nut 1 is contracted to adhere closely, and one side part of the jacket member 2 is formed into a diameter smaller than the internal thread minor diameter of the nut 1 to form a locking part 6. The covered nut A and an external thread body 4 are screwed with each other from the other side of the locking part 6, and the locking part 6 is screwed with the external thread 5 of an external thread body 4 protruded from one side part of the nut 1, thus integrating the locking part 6 with the external thread 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fastening method using a covering nut for assembling or connecting articles.

[0002]

2. Description of the Related Art When tightening a mounting member such as an article using a large number of bolts and nuts, whether the nuts or bolts are tightened with a predetermined tightening force (whether they are not forgotten to tighten), In addition, it is important that the nut or bolt after being tightened does not loosen.

Therefore, regarding the forgetting of tightening,
The present inventor has provided a technique in which a bolt or a nut is covered with a synthetic resin film, and it is possible to determine whether the tightening is completed or not tightened by the presence or absence of the synthetic resin film. (For example, Japanese Utility Model Application Laid-open No. Sho 62-190114, and Japanese Utility Model Application Laid-Open Sho 63-7
In addition, as a measure for preventing the loosening of the bolt or the nut described above, a spring washer or the like is interposed on the seat surface, or a split pin is engaged with the nut and the bolt.
Further, a double nut or a spring nut is attached to the threaded portion of the bolt on the upper surface of the nut.

However, the former countermeasure is to confirm that the film has been forgotten to be tightened due to detachment of the film.
The film removed from the bolts and nuts scatters in the vicinity of the mounting member and becomes dust, and not only is it difficult to clean up, but if the mounting member is a mechanical system, the bolt
The film detached from the nut mixes in and interferes with the operation of the mounting member.

Alternatively, the detached film becomes stuck in a box wrench which is a tightening tool, which causes a problem when tightening other nuts.

Further, in the latter countermeasure, even when a spring washer is used, when it is used in a place where vibration is generated, it may still loosen, and when a split pin, a double nut or a spring nut is used. In the case of tightening with a large number of bolts and nuts, the workability is significantly reduced. And other various problems.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and the outer cover member attached to the outer periphery of the nut is contracted and brought into close contact with one side of the outer cover member. In a covered nut in which a locking portion is formed by molding the portion into a diameter smaller than the root diameter of the female thread of the nut, the covering nut and the male screw body are screwed from the other side of the locking portion. By engaging the locking part with the male thread of the male screw body protruding from one side of the nut and integrating this locking part with the male thread, the detent of the nut or forgetting to tighten or not An object of the present invention is to provide a fastening method using a covering nut capable of preventing the mounted outer covering member from scattering.

[0008]

Means for Solving the Problems The means of the present invention for achieving the above-mentioned object is to install a shrinkable jacket member formed into a tubular shape on the outer periphery of a nut, and shrink the jacket member to nut the nut. In addition to closely contacting the outer periphery, one side of this jacket member is formed with a diameter smaller than the root diameter of the female thread of the nut to form a locking portion for the male thread of the male thread. Then, the encapsulation nut and the male screw body are screwed together from the other side of the engaging portion of the encapsulating nut, and the engaging portion of the encapsulating nut is moved to the nut by rotating the encapsulating nut or the male screw body. There is a fastening method in which a male nut body protruding from the side is screwed into the male thread, and the locking portion is integrated with the male thread.

Further, the covering nut and the male screw body are screwed together from the other side of the engaging portion of the covering nut, and the female nut and the male screw body of the nut are rotated by rotating the covering nut or the male screw body. There is a fastening method in which a locking portion is interposed between the screw and the locking portion integrated with a male screw.

Further, the encapsulation nut and the male screw body are screwed together from the other side of the engaging portion of the encapsulating nut, and the engaging portion of the encapsulating nut is expanded by rotating the encapsulating nut or the male screw body. Then, there is a fastening method using a covered nut in which this locking portion is integrated with the male screw by screwing the male screw body protruding from one side portion of the nut with the male screw.

Furthermore, the encapsulation nut and the male screw body are screwed together from the other side of the engaging portion of the encapsulating nut, and the engaging portion of the encapsulating nut is locked by rotating the encapsulating nut or the male screw body. The locking part is made integral with the external thread by screwing it onto the external thread of the external thread that protrudes from one side of the nut. The locking part is cylindrical and its cross-sectional shape is a perfect circle. Shaped or irregularly circular or eccentric.

Further, a shrinkable outer jacket member formed in a tubular shape is attached to the outer circumference of the nut, and the outer jacket member is contracted to be in close contact with the outer circumference of the nut, and one side portion of the outer jacket member is attached to the nut. A covering nut formed to have a substantially same shape or a larger diameter than the root diameter of a female screw to form a locking portion for the male screw of the male screw body by screwing the covering nut and the male screw body. After fastening or before fastening, the locking part is contracted, and it is brought into close contact with the male screw of the male screw that protrudes from one side of the nut, and the fastening part is integrated with the male screw. It is in.

[0013]

The present invention configured as described above has the following effects.

After the cylindrical shrinkable jacket member is mounted on the outer circumference of the nut and then the jacket member is contracted, the jacket member is brought into close contact with the outer circumference of the nut.

Further, one side portion of this outer cover member is formed to have a diameter smaller than the root diameter of the female thread of the nut, so that a covered nut having an engaging portion for the male thread of the male thread can be obtained.

In the first example, when fastening a mounting member such as an article, the covering nut and the male screw body are screwed with the mounting member sandwiched from the other side of the engaging portion of the covering nut. Then, when the nut or the male screw body is rotated by a tool, the tip of the male screw of the screw body reaches one side of the nut due to the screwing. Since the nut protrudes from one side portion and is screwed into the locking portion of the covering nut, the locking portion is combined with the male screw to be integrated.

Therefore, after tightening to the mounting member, the locking portion is screwed into the male thread of the male thread body, and the rotation of the nut in the loosening direction is prevented by the friction and the engagement with the male thread and the female thread. It will be a deterrent because it will be suppressed due to crowding.

The outer cover member that is in close contact with the outer periphery of the nut does not scatter due to the engaging portion connected to it even if it is peeled off when tightened by a tool.

In the second example, the engagement portion is sandwiched between the female thread of the nut and the male thread of the male thread by screwing the covering nut and the male thread, so that a gap between the both thread portions is generated. It is packed and the resistance of the nut is stopped by this resistance,
Even if the outer cover member that is in close contact with the outer periphery of the nut is peeled off by this locking portion, it is held integrally.

In a third example, the engagement portion formed by screwing the nut and the male screw body so as to cover a part of the screw hole on one side of the nut has a male screw body with the tip of the male screw. It is expanded and screwed onto the male screw of the male screw body, and the outer cover member becomes integral with the male screw by this locking portion.

Further, the locking portion formed by contraction of the outer cover member is cylindrical and has a cross-sectional shape of a perfect circle. Further, by forming it into a deformed circular shape or an eccentric shape, The screwed state of the male screw body to the male screw is sure.

Further, in the fourth example, the envelope nut of this example is provided with a shrinkable outer jacket member formed in a tubular shape on the outer circumference of the nut, and the outer jacket member is shrunk to be closely attached to the outer circumference of the nut. At the same time, one side portion of this outer cover member is formed into a shape substantially the same as or larger than the root diameter of the female thread of the nut to form a locking portion for the male thread of the male screw body. When fastening the mounting member, the mounting nut and the male screw body are screwed from the other side of the locking portion of the covering nut with the mounting member sandwiched therebetween, and the covering nut or the male screw body is secured. When rotated by a tool or the like, the tip of the male thread of the male thread reaches one side of the nut due to the screwing.

When the male screw is further rotated, the male screw protrudes from one side portion of the nut. When the engaging portion is contracted after or before the fastening by the screw engagement of the covered nut and the male screw body, The locking portion is in close contact with the external thread of the external thread body and is connected to and integrated with the external thread.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a fastening method using a covering nut according to the present invention will be described with reference to the drawings.

1 to 10, A is a cover nut,
A nut 1 and a shrinkable jacket member 2 which are used for assembling or connecting an article b such as a mounting member.
The nut 1 is basically configured by mounting a shrinkable jacket member 2 formed in a tubular shape on the outer circumference of the nut 1, shrinks the jacket member 2 by heating or the like, and closely adheres to the outer circumference of the nut 1. At the same time, the one side portion of the outer cover member 2 is formed to have a smaller diameter than the root diameter of the female thread 3 of the nut 1 as indicated by a symbol x in FIG. 1 (a) and FIG. An engaging portion 6 for the male screw 5 of the body 4 is formed.

As described above, the nut 1 is a conventional one used for assembling or connecting the article b such as a mounting member, and its type, screw type, material, etc. are limited. It is not something that will be done.

The shrinkable outer cover member 2 is a thin film having a predetermined thickness made of a synthetic resin material having a cylindrical shape and having a large shrinkage in the circumferential direction and having a heat shrinkability. Shaped ones are suitable and, if necessary, as shown in FIG.
As shown in (b) and FIG. 2 (f), perforations 7 may be provided in the axial direction or both in the axial direction and the circumferential direction so that the portion in close contact with the outer periphery of the nut 1 may be easily cracked.

The outer cover member 2 may be formed of a thin film material of rubber resin so as to elastically contact the nut 1 and the male screw 5 of the male screw body 4.

Although not shown in the drawing, the outer periphery of the nut 1 is subjected to engagement processing such as grooves and knurls, and the outer periphery of the nut 1 is contracted. The member 2 may be formed to be entangled.

In forming the locking portion 6,
As shown in FIG. 1 (a), the nut 1 is molded so as to cover a part of the screw hole on one side, and FIG.
As shown in (c) to (d), the nut 1 is formed into a tubular portion that axially projects from one side portion to a predetermined size.

Further, as shown in FIG. 2 (b), a predetermined size is inserted into the screw hole at one side of the nut 1, and the nut 1 is brought into close contact with the female screw 3 surface or the female screw 3 It is formed so as to be separated from the surface.

Further, the locking portion 6 is formed in a cylindrical shape in the axial direction, and its cross-sectional shape is formed in a circular shape with the screw hole of the nut 1 as shown in FIG. 3 (a). , A modified circular shape, that is, an elliptical shape as shown in FIG.
As shown in (c), it is formed into a continuous or discontinuous corrugated shape (irregular shape), and further, as shown in FIGS. 3 (d) and 2 (d), in the screw hole of the nut 1. On the other hand, it is formed eccentrically, and may be curved in a distortion shape that occurs inside and outside in the circumferential direction.

Further, as shown in FIG. 2 (c), one or both of the cylindrical locking portions 6 may be formed with a predetermined inclination with respect to the axial direction. Although not shown, this locking portion 6 may be formed into a tip bud shape in which the diameter gradually decreases from the side surface side of the nut 1 toward the tip thereof. From the root diameter at, the shape is formed into a smaller diameter as indicated by the symbol x in FIGS. 1 (a) and 2.

Further, as shown in FIG. 2 (e), the diameter may be relatively greatly reduced, and the locking portion 6 and the external thread 5 of the external thread 5 are in a soft-hardened state. Is appropriately set according to the degree.

The engaging portion 6 has its opening end side
As shown by a phantom line in FIG. 2A, the structure may be closed. In this case, since the gap between the male screw 5 and the female screw 3 is covered after the fastening to the mounting member b,
In addition to maintaining the airtightness and oil / watertightness of the fastening portion, it is possible to prevent concrete from adhering to the male screw 5 of the male screw body 4 protruding from the nut 1 at the place where concrete is placed.

Therefore, according to the above-described embodiment, when the two-member mounting members b, b as shown in FIG. 1C are fastened by the male screw body 4 such as a bolt and the nut 1, First, as shown in FIGS. 1 and 2, a hexagon nut 1
As shown in FIG. 1 (a), the shrinkable outer jacket member 2 formed in a tubular shape is attached to the outer periphery of the outer circumference of the outer shell as indicated by the phantom line, and the outer jacket member 2 is shrunk by heating. Member 2
Is closely attached to the outer periphery of the nut 1 as shown by the solid line in the figure.

Then, one side portion of the outer cover member 1 is formed to have a diameter smaller than the root diameter of the female screw 3 of the nut 1 by heat shrinkage, and the locking portion 6 for the male screw body 4 to the male screw 5 is formed. The other side portion of the outer cover member 1 is bent so as to engage with a part of the seat surface of the nut 1 and is supported by the outer edge of the seat surface, as shown in FIG.

The other side of the outer cover member 1 is shown in FIG.
As shown in (c), the nut 1 may be molded so as to be located on the peripheral surface.

As a result, the mounting members b and b are sandwiched and fastened from both sides thereof by the covering nut A and the male screw body 4. First, the male screw body 4 is inserted into the through holes 7 and 7 of the mounting members b and b.
The external thread 5 is passed through, and the internal thread 3 is screwed onto the external thread 5 protruding from one of the mounting members b, with the bearing surface side of the covering nut A corresponding to the mounting member b.

Then, when the covering nut A is rotated by applying a tool such as a wrench or a wrench, the tip portion of the male screw 5 of the screw body 4 is fitted with the nut 1 as the male screw 5 and the female screw 3 are screwed together. One side, that is, one that reaches the locking portion 6,
When the covering nut A is further rotated, the male screw 5 projects from one side portion of the nut A and is screwed into the locking portion 6 of the covering nut A as shown in FIG. The locking portion 6 is engaged with and coupled to the ridges and valleys of the screw of the male screw 5, and is integrated with the male screw body.

In the case of the locking portion 6 formed in a cylindrical shape as shown in FIG. 2 (a), similarly, as shown in FIG. The engaging portion 6 is in a screwed state, and the locking portion 6 is in a state in which the internal thread 6 a is formed by the external thread 5 and has a double nut shape with the nut 1.

Therefore, after tightening to the mounting members b, b, when the locking portion 6 is screwed onto the male screw 5 of the male screw body 4 and tries to rotate in the loosening direction of the nut 1, friction or friction thereof is generated. By engaging the male thread 5 and the female thread 3, the nut 1
On the side opposite to the bearing surface, the nut 1 is bitten by the internal thread 3 of the nut 1 to prevent the nut 1 from rotating in the reverse direction, which serves as a detent for the nut 1.

The outer cover member 2 that is in close contact with the outer peripheral surface of the nut 1 is peeled off from the nut 1 as shown in FIG. 1 (c) due to the force and resistance applied when tightening with a tool. The locking portion 6 connected to the peeling portion 2 has a male screw body 4
Since it is fixed to the male screw 5, it does not separate from the male screw 4 or the nut 1 and does not scatter to the outside.

In particular, in this cover nut A, the tightening position of the nut 1 can be visually confirmed by the locking portion 6, and as shown by the reference sign y in FIG. If it is decided that the nut 1 has reached this position, it can be judged from the outside that the tightening has been completed, and in the unlikely event that the nut 1 becomes loose, the dimensional change indicated by the symbol y will not occur. Since it appears on the screw 5, the returning state of the nut 1 can also be determined from the outside.

If the outer cover member 2 is made of a rubber-based resin thin film material and is elastically brought into contact with the nut 1 and the male screw 5 of the male screw body 4, the nut 1 can be made. At the time of screwing with the male screw body 4, the locking portion 6 is spread by the male screw 5 due to its elasticity, and the screwing progresses. It is possible to generate a large frictional resistance on both the members 5 and 6 by contacting them.

Next, as shown in FIG. 2B, in the state where the engaging portion 6 of the covering nut A is pushed into the screw hole of the nut 1, the female screw 3 in the covering nut A is shown. When the male screw 5 of the male screw body 4 is screwed, as shown in FIG. 5A, the tip of the male screw 5 pushes the locking portion 6 and gradually feeds it outward.

When the nut A or the male screw body 4 is further rotated, the locking portion 6 finally projects to the outside of the nut 1. If the rotation is continued as it is, the locking portion 6
While being familiar with the male screw 5, as shown in FIG. 5B, the female screw 6a is formed by this male screw,
It becomes a double nut shape with the nut 1.

When the mounting member b is fastened to the covering nut A, the same working effect as that of the above-described example is exhibited.

Next, as shown in FIG. 2 (b), the engaging portion 6 of the covering nut A is pushed into the screw hole of the nut 1 and the peak and valley portions of the female screw 3 are engaged. Locking part 6
When the male thread 5 of the envelope nut A is screwed onto the male thread 5 of the male thread body 4 in the state in which is closely attached,
As shown in FIG. 3, the tip portion of the male screw 5 is screwed into the locking portion 6.

When the nut A or the male screw body 4 is further rotated, the locking portion 6 is sandwiched between the male screw 5 and the female screw 3, as shown in FIG. 6 (b). In addition, the gap between the male screw 5 and the female screw 3 is eliminated, and so-called caulking is performed in the tightened state.

Even when the mounting member b is fastened to the covering nut A, the same working effects as those of the above-described examples are exhibited, and the covering nut A of each example illustrated in the present embodiment is as follows. The configuration of the locking portion 6 also has the same effects as the above, and thus detailed description thereof will be omitted.

Further, the covering nut A in the embodiment of the present invention.
As shown in FIG. 2 (b), a spring washer 8 (a variety of springs may be used) is attached to the bearing surface side of the nut 1, and the nut 1 is covered with the shrinkable jacket member 2. As shown in FIG. 2 (f), the spring 1 and the flat washer 9 are attached to the bearing surface side of the nut 1, and the shrinkable jacket member 2 is provided.
Although not shown, other members such as washers, packings, O-rings, etc. required for fastening, tightening, detenting, etc. can also be covered.

In the case of covering the nut 1 with the jacket member 2, as shown in FIG.
It is also possible to cover with the nut 1 described above by attaching a stopper member 10 required for fastening, tightening, detenting and the like of washers, packings, O-rings and the like.

FIG. 8 shows a fastening method according to another example of the covering nut A. In this covering nut A, the shrinkable covering member 2 formed in a tubular shape on the outer circumference of the nut 1 is shown in FIG. As shown in a), the nut 1 is attached by shrinking the outer cover member 2
Adhere to the outer circumference.

At this time, the locking portion 6 of the outer cover member 2 is formed in one side portion to have substantially the same shape or a larger diameter than the root diameter of the female screw 3 of the nut 1.

Then, as shown in FIG. 8 (b), after the fastening nut A is fastened by screwing the male screw body 4 or before the fastening, the locking portion 6 is further contracted by heating or the like, By bringing the locking portion 6 into one piece with the male screw 5 by closely adhering it to the ridges and valleys of the male screw 5 of the male screw body 4 projecting from one side of the nut 1, the above-described action and effect are exhibited. Let

At this time, as shown in FIG. 9, if the male screw 5 of the male screw body 4 is provided with a recess or an engaging portion 11 such as a different screw pitch, the engaging portion 6 and the male screw 5 are separated from each other. The bond between is stronger.

When the nut 1 is covered with the outer cover member 2, as shown in FIG. 10, two or a plurality of nuts 1 and 1 provided in a double nut state can be externally mounted. The combination etc. can be performed arbitrarily.

[0059]

As described above, according to the method of fastening with the nut of the present invention having the above-described structure, the outer jacket member covered with the nut is screwed into the male screw body of the nut and integrated with the male screw. Therefore, even if the outer cover member that was in close contact with the outer circumference of the nut is peeled off during fastening, the outer cover member in this part is connected to the locking part and does not separate from the nut or male screw body. , Which does not scatter near the mounting member to become dust, and does not cause a trouble to a machine or the like due to mixing of the sheath member due to this, No hassle to clean.

Alternatively, the detached jacket member does not get stuck in a box wrench which is a tightening tool and causes a trouble when tightening other nuts.

Since the locking portion is screwed into close contact with the crests and valleys of the male thread, even if the nut tries to rotate in the loosening direction, the locking portion is caught between the male thread and the female thread of the nut. As it prevents the nut from rotating, it serves as a detent.

When the locking portion comes into close contact with the male thread portion of the male screw body, this portion serves as a mark for tightening. Therefore, the locking portion is located on the male screw protruding from the nut, so that the nut is tightened. It will prevent you from forgetting. And so on.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing each example of a fastening state of a covering nut used in a fastening method with a covering nut according to the present invention.

FIG. 2 is a cross-sectional view showing another example of the covering nut used in the fastening method with the covering nut according to the present invention.

FIG. 3 is a front view showing still another example of the covering nut used in the fastening method with the covering nut according to the present invention.

FIG. 4 is a cross-sectional view showing an example of a screwed state with the male screw body of the covering nut in FIG. 2 (a).

FIG. 5 is a cross-sectional view showing an example of a screwed state with the male screw body of the covering nut in FIG. 2 (b).

FIG. 6 is a cross-sectional view showing another example of a screwed state with the male screw body of the covering nut in FIG. 2 (b).

FIG. 7 is a cross-sectional view showing a state in which a retaining member is interposed in the covering nut A.

FIG. 8 is a cross-sectional view showing each example of the fastening state of the covering nut used in another example of the fastening method with the covering nut according to the present invention.

FIG. 9 is a cross-sectional view showing a state where a locking portion is in close contact with a male screw provided with an engaging portion.

FIG. 10 is a cross-sectional view showing a covered nut using a plurality of nuts.

[Explanation of symbols]

 A Cover nut 1 Nut 2 Shrinkable jacket member 3 Female screw 4 Male screw body 5 Male screw 6 Locking part

Claims (5)

[Claims] 1. A shrinkable jacket member formed into a tubular shape is attached to the outer circumference of a nut, and the jacket member is contracted to be in close contact with the outer circumference of the nut, and one side portion of the jacket member is attached to the nut. A nut having a smaller diameter than the root diameter of a female thread and having a locking portion for locking the male thread of the male thread, wherein the nut and the male thread are locked in the nut. Screw from the other side of the part, and by rotating the nut or male screw body, the locking part of the nut is screwed to the male screw of the male screw projecting from one side of the nut. A fastening method using a covered nut, wherein a locking portion is integrated with a male screw. 2. A shrinkable outer jacket member formed in a tubular shape is attached to the outer circumference of the nut, and the outer jacket member is shrunk and brought into close contact with the outer circumference of the nut, and one side portion of the outer jacket member is attached to the nut. In a covered nut having a smaller diameter than the root diameter of a female thread and formed with a locking portion for the male thread of the male thread, the nut and the male thread are locked in the nut. Screw from the other side of the part, and by rotating the nut or the male screw body, the engaging part is interposed between the female thread of the nut and the male thread of the male thread body. A fastening method using a covered nut, which is integrated with the above. 3. A shrinkable jacket member formed into a tubular shape is attached to the outer circumference of the nut, and the outer jacket member is contracted and brought into close contact with the outer circumference of the nut, and one side portion of the jacket member is attached to the nut. A covering nut having a diameter smaller than the thread diameter of the female thread and formed so as to cover a part of the screw hole on one side of the nut to form a locking portion for the male thread of the male thread body, The encapsulation nut and the male screw body are screwed together from the other side of the engaging portion of the encapsulating nut, and the engaging portion of the encapsulating nut is expanded by rotating the encapsulating nut or the male screw body. A fastening method using a covered nut, characterized in that a male screw body protruding from one side is screwed onto the male screw, and the locking portion is integrated with the male screw. 4. A shrinkable outer jacket member formed in a tubular shape is attached to the outer circumference of the nut, and the outer jacket member is contracted to be in close contact with the outer circumference of the nut, and one side portion of the outer jacket member is attached to the nut. In a covered nut having a smaller diameter than the root diameter of a female thread and formed with a locking portion for the male thread of the male thread, the nut and the male thread are locked in the nut. Screw from the other side of the part, and by rotating the nut or male screw body, the locking part of the nut is screwed to the male screw of the male screw projecting from one side of the nut. A fastening method using a covered nut, characterized in that the locking portion is integrated with a male screw, and the locking portion is formed in a cylindrical shape and its cross-sectional shape is formed into a perfect circle shape, a modified circular shape or an eccentric shape. . 5. A shrinkable outer jacket member formed in a tubular shape is attached to the outer circumference of the nut, and the outer jacket member is contracted to be in close contact with the outer circumference of the nut, and one side portion of the outer jacket member is attached to the nut. A covering nut formed to have a substantially same shape or a larger diameter than the root diameter of a female screw to form a locking portion for the male screw of the male screw body by screwing the covering nut and the male screw body. A package characterized in that the locking portion is contracted after or before the fastening and is brought into close contact with the male screw of the male screw body protruding from one side of the nut, and the locking portion is integrated with the male screw. Fastening method with nuts.