WO2003067104A1

WO2003067104A1 - Locking nut

Info

Publication number: WO2003067104A1
Application number: PCT/JP2003/001098
Authority: WO
Inventors: Ryusuke Mashima
Original assignee: Mashima Seisakusyo Co., Ltd.
Priority date: 2002-02-04
Filing date: 2003-02-04
Publication date: 2003-08-14
Also published as: AU2003211911A1

Abstract

A locking nut adapted to impart a loosening-preventive function to a main nut itself by plastically deforming the internal thread of the main nut, wherein although the tightening operation is simplified, the loosening of the main nut can be prevented even if the locking nut becomes loosened. A locking nut (1) adapted to be tightened from above a main nut (2) threadedly engaged on an external thread (20) to thereby prevent the loosening of the main nut, wherein the locking nut is made of a material having higher hardness than that of the material of the main nut and has a projection (13) formed around the peripheral edge of the threaded hole in the axial end surface, the projection being pressed at its front end against the peripheral edge of the threaded hole in the main nut to plastically deform the internal thread of the main nut.

Description

Description Lock nut Technical field

The present invention relates to a fastening technique for various mechanical devices and building steel frames, and more particularly, to a fastening nut which is screwed onto a male screw portion (such as a port) from a fastening nut. The present invention relates to a locking nut for preventing loosening. Background art

Conventionally, a port and a nut as fastening means may be gradually loosened by an external force such as vibration, and various means have been proposed as means for preventing such loosening of the nut.

Among these, as a typical loosening prevention means, a fastening structure using a double nut using two nuts of the same size (same outer diameter) is well known.

This double nut is designed so that one nut (final fastening nut) screwed to a male thread (porto etc.) is tightened from the other nut (locking nut). Both nuts are prevented from loosening by the action of tightly tightening the nuts.

In such a double nut, it is necessary to tighten the two nuts to ensure that they are in close contact with each other. For this reason, while tightening one lock nut, rotate the other nut in the loosening direction. As a result, it is necessary to perform a complicated work of firmly tightening both nuts.

If the lock nut is loose, double-nut There is a problem that the function of the nut is lost and the nut for final fastening cannot be prevented from loosening.

In the conventional double nut, the seating surface (axial end surface) of the locking nut has the same area as the seating surface of the final fastening nut. When the lock nut is rotated, the nut for final tightening rotates together with the lock nut, and the nuts cannot be tightened. .

Therefore, in order to prevent this co-rotation, complicated work such as turning the nut for final tightening in the loosening direction while tightening the lock nut and forcibly tightening both nuts together is forced. .

Conventionally, for example, as described in Japanese Patent Application Laid-Open No. H10-61645 and Japanese Patent Application Laid-Open No. H11-31520, a protrusion is formed on a peripheral portion of a screw hole on an axial end face. Lock nuts with a projection are known.

When the conventional lock nut is tightened to the nut for final tightening, the protrusion protruding from the peripheral portion of the screw hole is crushed, and the female screw portion and the male screw portion (porto, etc.) of the nut for final tightening are removed. The nut is to be caught in the threaded portion, thereby restricting the rotation of the nut for final fastening and preventing the nut from turning.

As described above, the protrusion formed on the conventional lock nut functions only when it is crushed, and is not a protrusion for plastically deforming the female screw portion of the nut for final tightening. There is a problem in that the locknut cannot be reused as a locknut because it is crushed.

In particular, since the conventional lock nut functions only when the projections are crushed, the hardness of the material must be equal to or less than the hardness of the material of the nut for final fastening. In addition, there is a problem that the projection cannot be reused as a lock nut because the projection is crushed.

The present invention has been made in order to solve the above-described problems, and securely tightens both nuts while preventing the nuts for final tightening from rotating together when the nuts for locking are tightened. The primary task is to provide a locking nut that can be matched. In addition, the female thread of the final fastening nut is plastically deformed by the locking nut, and the final fastening nut itself has a function of preventing loosening, so that the fastening work is simplified and the locking nut is further reduced. The second problem is to prevent the nut for final tightening from being loosened even if the lock is loosened, and to provide a locking nut that can be reused. . Disclosure of the invention

In order to solve the above first problem, a locking nut (claim 1) of the present invention comprises:

A locking nut that is designed to prevent loosening of the final fastening nut by tightening from above the final fastening nut screwed into the male thread.

An annular projection is formed on the axial end face,

An annular seating surface for contacting the seating surface of the nut for final fastening is formed at the tip of the annular projection.

The configuration was such that the area of the annular seating surface was formed smaller than the area of the axial end surface.

This locking nut (Claim 1) is used by being tightened from above a nut for final tightening screwed to a male thread portion such as a port. That is, the annular projection has a nut for final tightening. With the male thread so that it faces <.

When the locking nut is screwed in this way, the annular seating surface of the annular projection comes into contact with the seating surface of the nut for final fastening. By further tightening the lock nut, the lock nut and the final nut are firmly fastened, but at this time, the nut comes into contact with the seat surface of the final nut. Since the area of the annular seating surface is formed smaller than the area of the axial end surface, the contact area between the two nuts can be reduced. This makes it possible to prevent the nuts for final tightening from rotating together with the tightening of the nuts for locking, and to increase the tightening pressure by reducing the contact area. Can be tightened.

In addition, because of the annular seating surface, the annular seating surface is pressed annularly against the seating surface of the final fastening nut when the locking nut is tightened. The pressing force can be applied evenly to the seating surface of the nut for final fastening, and when the annular projection breaks even if the annular seating surface bites into the seating surface of the nut for final fastening. As a result, pressure can be reliably applied to the nut for final fastening.

In order to solve the above second problem, a locking nut of the present invention (claim 2)

A locking nut that is tightened from the final fastening nut screwed into the male thread to prevent the final fastening nut from loosening.

It is made of a material having a higher hardness than the material of the nut for final fastening. The female screw part of the nut for final fastening is formed with a protrusion for plastic deformation. The locking nut according to the present invention (Claim 2) is used by tightening from above a final fastening nut screwed into a male thread portion such as a porto, that is, a protrusion faces the final fastening nut. Screw it into the male screw part.

When the locking nut is screwed in this way, the projection is formed at the periphery of the screw hole, and the tip of the projection comes into contact with the periphery of the screw hole of the nut for final fastening. . When the lock nut is further tightened, the tip of the protrusion is pressed against the periphery of the screw hole of the final tightening nut, and the pressing force causes the female screw of the final tightening nut. The part is plastically deformed.

Due to the plastic deformation of the female thread, the clearance between the female thread and the male thread is lost, and the female thread and the male thread are in close contact with each other, which increases the rotational resistance of the nut for final tightening. Therefore, the nut for final tightening has its own locking function.

Therefore, even if the lock nut is loosened, the nut for final tightening itself can prevent the nut from loosening.

Also, unlike the conventional method, complicated work such as tightening both nuts so that the lock nuts and the final tightening nuts are in close contact with each other is not required, and the tightening nuts are simply tightened. It is possible to prevent loosening of the nut for final tightening with a simple operation.

In particular, in the present invention, as a means for plastically deforming the female screw portion of the nut for final tightening by a pressing force accompanying the tightening of the nut for locking, the hardness of the material of the nut for locking is mainly determined. The hardness is higher than the hardness of the nut material.

Therefore, even if the tip of the projection is cut into the nut for final fastening, the projection is not crushed, and the female screw portion of the nut for final fastening can be securely plastically deformed. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a cross-sectional view of a double-nut structure using a locking nut of an embodiment according to claim 1 of the present invention. FIG. 2 is a half sectional view of the lock nut. FIG. 3 is a half sectional view showing another example of the annular projection. FIG. 4 is a half sectional view showing another example of the annular projection. FIG. 5 is a half cross-sectional view showing another example of a nut for sucking. FIG. 6 is a cross-sectional view of a double-nut structure using the locking nut of the embodiment according to claim 2 of the present invention. FIG. 7 is a bottom view of the locking nut. FIG. 8 is an enlarged sectional view of the locking nut. FIG. 9 is an enlarged cross-sectional view showing another example of the projection formed on the locking nut. FIG. 10 is an enlarged half-sectional view showing another example of the protrusion formed on the locking nut. FIG. 11 is an enlarged half-sectional view showing another example of the protrusion formed on the locking nut. FIG. 12 is an enlarged half-sectional view showing another example of the protrusion formed on the locking nut. FIG. 13 is an enlarged half-sectional view showing another example of the protrusion formed on the locking nut. FIG. 14 is a bottom view showing another example of the locking nut of the present invention. FIG. 15 is an enlarged sectional view of the locking nut. FIG. 16 is a bottom view showing another example of the locking nut of the present invention. FIG. 17 is a cross-sectional view of the locking nut. FIG. 18 is a bottom view showing another example of the lock nut of the present invention. FIG. 19 is a cross-sectional view of the locking nut. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment corresponding to claim 1 of the present invention will be described with reference to an embodiment shown in the drawings.

FIG. 1 is a cross-sectional view of a double-nut structure using the locking nut of the embodiment, and FIG. 2 is a half-sectional view of the locking nut.

As shown in Fig. 2, this lock nut 1 is It is formed in a hexagonal nut shape with a female screw 11 formed on its surface, and an annular projection 13 is formed on one axial end surface 12 at the periphery of the screw hole.

The other axial end surface 14 may be formed as a flat seat surface, or may be formed with a similar annular projection.

The annular projection 13 is formed in a cylindrical shape at the periphery of the screw hole of the axial end face 12, and a tip thereof is formed in a circularly continuous annular seating face 15. The area is formed smaller than the area of the axial end face 12.

In this case, the area of the annular seating surface 15 is made smaller than the area of the axial end surface 12 by making the width a of the annular seating surface 15 smaller than the width b from the nut outer periphery 16 to the screw hole 10. Usually, the area of the annular seating surface 15 is set in consideration of the amount of reduction in the contact area and the strength of the annular projection, and a = l Z 2 b and a = l It is preferable to set b, a = lZ4b.

3 and 4 are half sectional views showing other examples of the annular projection.

The example of Fig. 3 shows an example in which an annular projection 13 is formed in the middle part between the nut outer periphery 16 of the axial end face 12 and the screw hole 10; the example of Fig. 4 shows a screw from the nut outer periphery 16 This is an example in which an annular projection 13 inclined in a tapered shape toward the hole 10 is formed.

As shown in FIG. 1, the lock nut 1 is used as a double nut with the final tightening nut 2. In this case, the male nut of the bolt 4 passed through the members 3 to be tightened is used. After the nuts 2 for final fastening are screwed into the screw portions 40 to fasten the members to be fastened 3, 3, the locking nut 1 is moved so that the annular projection 13 faces the nut 2 for final fastening. Screw it into the male thread part 40 of the bolt 4.

When the locking nut 1 is screwed in this way, the annular projection 1 The annular seating surface 15 of 3 contacts the seating surface 20 of the nut 2 for final fastening. Then, by further tightening the locking nut 1, the locking nut 1 and the final tightening nut 2 are firmly fastened. Since the area of the annular seating surface 15 that contacts the seating surface 20 of the fastening nut 2 is formed smaller than the area of the axial end surface 12, the contact area between both nuts 1 and 2 is reduced. It is possible to prevent the nuts 2 for final tightening from rotating together with the tightening of the nuts 1 for locking, and to increase the tightening pressure by the reduced contact area. Therefore, the two nuts 1 and 2 can be securely tightened.

In addition, since the annular seating surface 15 is used, the annular seating surface 15 is annularly pressed against the seating surface 20 of the final tightening nut 2 as the locking nut 1 is tightened.

Therefore, the pressing force accompanying the tightening of the locking nut 1 can be evenly applied to the seating surface 20 of the nut for final tightening 2, and the annular seating surface 15 can be applied to the nut for final tightening. Even if it penetrates into the seating surface 20 of the second 2, the annular projection 13 is not crushed, and the pressure can be reliably applied to the nut 2 for final fastening.

Next, FIG. 5 is a half-sectional view showing another example of a locking nut. The locking nut 1 is formed by drawing a steel plate with a press to form the main body 1a. After molding, the female screw 11 is machined to form a locking nut 1.The shape of the annular projection 13 can be formed in the same manner as in FIGS. 2, 3, and 4. it can.

The material of the lock nut 1 is not particularly limited, and may be steel (SWCH 8-: L0, SS400, S45C, etc.), high tension steel, stainless steel (SUS3 04, etc.), alloy steel (SCM 435, etc.), titanium, and other synthetic resins such as aluminum, copper, rigid PVC, polycarbonate, etc. if they have a higher hardness than the material of the nut 2 for final fastening. Etc. It can be used, and the shape is not limited to a hexagonal nut shape, but may be a square nut shape or the like.

Next, an embodiment corresponding to claim 2 of the present invention will be described with reference to an embodiment shown in the drawings.

FIG. 6 is a sectional view of a double nut structure using a locking nut according to an embodiment of the present invention, FIG. 7 is a bottom view of the locking nut, and FIG. 8 is an enlarged sectional view of the locking nut. It is.

As shown in FIGS. 7 and 8, the nut 6 for locking has a hexagonal nut shape in which a female screw portion 61 is formed on the inner peripheral surface of the screw hole 60. Four single-width protrusions 63 are formed at the same interval along the periphery of the screw hole of one axial end face (bottom face) 62 of the nut body 6a.

The other end surface (upper surface) 64 in the axial direction may be formed on a flat surface, or may have a similar projection.

Also, the shape of the nut body 6a is not limited to a hexagonal nut shape, but can be formed into a square nut shape, and the nut body 6a can be formed by drawing a steel plate by pressing. Can also.

Each of the protrusions 63 is formed integrally with the nut body 6a at the periphery of the screw hole of the axial end face 62, and the side surface thereof is formed in a convex arc shape as shown in FIG. However, its cross-sectional shape is formed in a square shape.

The number of protrusions 63 is not limited to four in the embodiment, but may be one, or two, three, five, six, or the like.

Further, the side surface shape of the protrusion 63 may be a square shape as shown in FIG. 9, the cross-sectional shape thereof is a triangular shape as shown in FIG. 10, a chevron shape as shown in FIG. It can be formed in a semicircular shape as shown in FIG. 12 and in a circular arc shape as shown in FIG.

The locking nut 6 is used for final tightening as shown in FIG. Nut 7 is used as a double nut.

In this case, the material of the final fastening nut 7 is generally made of mild steel, but the locking nut 6 of the present embodiment has a higher hardness than the material of the final fastening nut 7. It is formed of a material.

Specific materials include steel (SWCH8-10, SS400, S405C, etc.), high tension steel, stainless steel (SUS304, etc.), alloy steel (SCM435) Etc.), titanium, and other synthetic resins such as aluminum, copper, hard vinyl chloride-polycarbonate, etc., as long as the hardness is higher than the material of the nut 2 for final fastening.

Therefore, as shown in FIG. 6, the final fastening nut 7 is screwed into the male screw portion 90 of the bolt 9 passed through the members to be fastened 8, 8 to fasten the members to be fastened 8, and then the The nut 6 is screwed into the male screw portion 90 such that the projection 63 faces the nut 7 for final fastening.

As a result, the tip of the projection 63 comes into contact with the periphery of the screw hole of the nut 7 for final tightening, but when the nut 6 for locking is further tightened, the tip of the projection 63 becomes The female screw 70 is plastically deformed at the screw hole opening of the nut 7 by the pressing force against the peripheral edge of the screw hole of the nut 7.

When the female screw portion 70 is plastically deformed in this manner, the clearance between the female screw portion 70 and the male screw portion 90 is lost, and the female screw portion 70 and the male screw portion 90 are firmly adhered. However, the rotational resistance of the nut 7 for final tightening is accordingly increased, so that the nut 7 for final tightening itself has a locking function.

Therefore, even if the locking nut 6 is loosened, the final fastening nut 7 can prevent the loosening of the locking nut 6 by itself, and it is also easy to simply tighten the locking nut 6. It is possible to prevent the nut 7 for final tightening from being loosened by a simple operation. In particular, as a means for plastically deforming the female thread portion 70 of the nut 7 for final fastening by the pressing force accompanying the tightening of the nut 6 for locking, the material of the material of the locking nut 6 is used. The hardness is higher than the hardness of the material of the nut 7 for final fastening.

Therefore, even if the tip of the projection 63 bites into the nut 7 for final fastening, the projection 63 is not crushed, and the female screw portion 70 of the nut 7 for final fastening is securely plastically deformed. be able to.

Next, FIG. 14 is a bottom view showing another example of the locking nut, and FIG. 15 is an enlarged sectional view of the locking nut.

The lock nut 6 has three long protrusions 63 formed at the same interval along the periphery of the screw hole of one axial end surface (bottom surface) 62 of the nut body 6a. .

The other axial end surface (upper surface) may be formed as a flat surface, or a similar protrusion may be formed.

Each of the protrusions 63 is formed integrally with the nut body 6a at the periphery of the screw hole of the axial end face 62, and the side surface thereof is formed in a convex arc shape as shown in FIG. The cross-sectional shape is square.

The number of the protrusions 63 is not limited to three in the embodiment, but may be one, or two, four, five or the like.

Further, the side surface shape of the protrusion 63 can be formed in a square shape as in the first embodiment, and the cross-sectional shape thereof is as shown in FIG. 10, FIG. 11, FIG. 12, FIG. It can be formed in a triangular shape, chevron shape, semicircular shape, or arc shape at the tip as shown in Fig.

Next, FIG. 16 is a bottom view showing another example of the locking nut, and FIG. 17 is a cross-sectional view of the locking nut.

This locking nut 6 is provided on one axial end face of the nut body 6a. Two

(Bottom) An annular protrusion 63 is formed on the body along the periphery of the screw hole 62.

Further, the cross-sectional shape of each of the protrusions 63 can be formed in a rectangular shape as in the first embodiment, and as shown in FIGS. 10, 11, 12 and 13. It can be formed into a triangular shape, chevron shape, semicircular shape, or arc shape at the tip. Further, the tip surface of the projection 63 can be formed in a wavy shape, a tooth shape, a saw blade shape, or the like.

Next, FIG. 18 is a bottom view showing the locking nut of the fourth embodiment, and FIG. 19 is a sectional view of the locking nut.

The locking nut 6 has four hemispherical protrusions 63 integrally formed at the same interval along the periphery of the screw hole of one axial end surface (bottom surface) 62 of the nut body 6a. Have been.

The number of protrusions 63 is not limited to four in the embodiment, but may be one, or two, three, five, six, seven, eight, ten, etc. be able to. Industrial applicability

As described above, according to the locking nut of the present invention (claim 1), the area of the annular seating surface that comes into contact with the seating surface of the nut for final fastening is formed smaller than the area of the axial end surface. As a result, the contact area between the two nuts is reduced to prevent the nuts for final tightening from rotating together with the tightening of the locking nuts, and tightening is performed by the reduced contact area. Increase the pressure and tighten both nuts securely. Can be.

In addition, because of the annular seating surface, the pressing force accompanying the tightening of the locking nut can be evenly applied to the seating surface of the nut for final tightening. Even if it cuts into the seat surface of the gut, the annular projection does not collapse, and pressure can be reliably applied to the nut for final fastening.

Further, according to the locking nut of the present invention (claim 2), the female screw portion of the final tightening nut can be plastically deformed by tightening the locking nut. It can have its own locking function.

Also, unlike the past, complicated work such as tightening both nuts so that the lock nut and the final tightening nut are in close contact with each other is not required, and the lock nut is simply tightened. It is possible to prevent loosening of the nut for final tightening with a simple operation.

In particular, since the hardness of the material of the locking nut is higher than the hardness of the material of the nut for final fastening, the protrusions are not crushed, and the female screw portion of the nut for final fastening is securely formed. It can be plastically deformed.

Claims

The scope of the claims

1. A locking nut that is to be tightened from the final fastening nut screwed into the male thread to prevent the final fastening nut from loosening.

An annular projection is formed on the axial end face,

An annular seating surface for contacting the seating surface of the nut for final fastening is formed at the tip of the annular projection,

A locking nut characterized in that the area of the annular seating surface is smaller than the area of the axial end surface.

2. A locking nut that is to be tightened from the nut for final tightening screwed into the male thread to prevent the nut for final tightening from loosening.

It is formed of a material having a hardness higher than the hardness of the material of the nut for final tightening. The tip of the nut is pressed against the peripheral portion of the screw hole on the end face in the axial direction. A locking nut, wherein a projection is formed for plastically deforming a female screw portion of the fastening nut.