JPH073245B2 - Nut and mounting method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nut and its mounting method.

[0002]

2. Description of the Related Art A so-called crimp nut having a cylindrical protrusion on the seat surface side is used. This cylindrical protrusion is formed by backward extrusion or forward extrusion in the screw axis direction.

[0003]

When the nut provided with the above-mentioned cylindrical protrusion is crimped, the crimped portion is not flush with the lower surface of the plate, but rather deformed so as to be located below the lower surface of the plate. I often do it. For this reason, the range of adaptation to the plate thickness is poor, and problems such as fastening defects occur when plates with an inappropriate thickness are fastened.

On the other hand, a welding nut is also used, but it is not suitable for a surface-treated member because the plate surface becomes hot during welding.

It is an object of the present invention to solve the above-mentioned inconveniences and to provide a nut having a large adaptable range with respect to the plate thickness and a mounting method thereof.

[0006]

The first aspect of the present invention is directed to large diameter portions 32 and 52 protruding outward from the roots of cylindrical small diameter portions 34 and 54.
And the cylindrical small-diameter portion 3 of the large-diameter portions 32 and 52.
A gist is a nut characterized in that a seating surface is provided on the side of 4, 54 and annular recesses 31, 51 are provided near the inside of the large diameter portions 32, 52.

A second aspect of the invention is to use the above-mentioned nut as a mating member 4
0, 42, wherein the cylindrical small-diameter portions 34, 54 are inserted into the holes of the mating members 40, 42, and the cylindrical small-diameter portions 34, 54 are pressed to form the holes. The gist is the method of installing the nut, which is characterized by pressing it against the wall surface of the.

[0008]

When mounted, the cylindrical small-diameter portions 34 and 54 are pressed, and the excess thickness is pushed into the annular recesses 31 and 51. Then, the cylindrical small-diameter portions 34 and 54 are pressed against the wall surfaces of the holes of the mating members 40 and 42. At this time, the cylindrical small-diameter portion 34,
The tip portion of 54 is flush with the surface of the plate on which the nuts 30 and 50 are provided or is dented from the plate surface. In other words, the return-shaped recesses 31 and 51 act as caulking spaces.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 7 is a side view showing an embodiment of a nut (also referred to as a crimp nut) according to the present invention with a cross section taken on only one side. FIG. 8 is a top view thereof, and FIG. 9 is an end view seen from below.

The top side 36 of the nut 30 has a hexagonal shape like a normal hexagonal nut. The nut 30 has a through hole, and an internal thread 37 is formed on the inner surface on the top side thereof. A cylindrical small diameter portion 34 protruding in the axial direction is formed on the bottom side of the nut. Triangular mountain serrations 35 are formed on the outside of the cylindrical small-diameter portion 34. Cylindrical small diameter part 34
A brim 32 (large diameter portion) protruding outward is formed at the base of the. The bottom side of the brim 32 is a seating surface. Between the female screw portion 37 and the inner surface of the cylindrical small diameter portion 34, that is, the collar 32
An annular recess 31 is formed in the vicinity of the inside.

10 and 11 show a metal plate 4 having holes.
It is sectional drawing which shows the state which crimped the nut 30 to 0 and 42. At the time of crimping, the crimping tools 41 and 43 are used to apply a deforming pressure from below in the drawing. By this pressing, the cylindrical small-diameter portion 34 slightly expands to the outside, and the triangular mountain serrations bite into the metal plates 40 and 42. Figure 10
Shows the case where the plate thickness is 2 mm, and in FIG. 11, the plate thickness is 0.5 mm.
The case of mm is shown. By adjusting the angle α and the length h of the caulking tool, the triangular mountain serration 35
You can set the bite strength of the board.

FIG. 12 shows an example of the nut 50 when the crimping pressure during molding is lowered. In this example, the recess 51 is formed to be large.

The nuts 30 and 50 are suitable for mounting parts and the like on a metal plate having a wall thickness of 0.5 mm or more.

Such a nut also has the following advantages.
Since it can be mounted at room temperature, there is no change due to heat during plate and plate surface treatment. Oxidation does not accelerate at room temperature. The production rate is easier to increase with plastic caulking than with welding. The working environment temperature drops. Moreover, spatter does not occur. If you prepare a mobile device, you can install it outside the factory. It is possible to insert the seal packing between the nut and the plate. It is also possible to attach a metal nut to the resin plate.

Next, an example of a method for manufacturing the nut of the present invention will be described.

First, a round bar material, which is a material for a nut, is sheared to obtain many material pieces 10 shown in FIG. Both ends of each piece are sheared surfaces.

The plastic working carried out at the following first to fifth stations is cold forging, and can be carried out, for example, by a 5-step (5-station) parts homer or a nut homer. In FIGS. 2 to 6, the upper side is the punch side and the lower side is the die side, but this may be reversed. In addition,
4 to 6 are cross-sectional views along two radii (corner and side of hexagon nut) orthogonal to each other in each molded body. 4 to 6, reference numerals 1, 1a and 1b are dies, 2 is a hole punch, 3 is a projecting pin, 4 is a center pin, 5 is a sleeve, 6 and 6a punches, 7 is a projecting sleeve, and 8 is different. It is the center pin.

End face shaping is performed at the first station. As a result, the end surface of the material piece 10 of FIG. 1 is shaped,
The molded body 11 shown in FIG. 2 is obtained.

In the second station, pre-drilling is performed. As a result, the preliminary hole 13 is formed in the molded body 11 of FIG. 2, and the molded body 12 having the shape shown in FIG. 3 is obtained.

At the third station, punching and hexagonal molding are carried out to obtain a molded body 14 shown in FIG. That is,
Holes 15 are drilled and cylindrical projections 16 are formed in the axial direction by front extrusion or rear extrusion. A shallow hole 17 is formed on the opposite surface. The shallow hole side is 18
The cross section is formed into a hexagonal shape as shown by.

In the fourth station, preforming of the caulking portion and hole penetration are performed. As a result, as shown in FIG. 5, the tip of the cylindrical protruding portion becomes the small diameter portion 20, the brim prototype 22 is formed at the base of the small diameter portion 20, and the concave prototype 2 is formed inside thereof.
1 is formed. Further, a through hole 23 is formed along the central axis.

The fifth station is for forming a caulking portion, a brim and a triangular mountain serration. By pressure molding in the axial direction at the fifth station, a collar 26 protruding outward is formed at the base of the small diameter portion 25 as shown in FIG. A seat surface 27 is formed on the bottom of the brim 26. A recess 28 is formed near the inside of the brim 26. Further, about 40 triangular mountain serrations are formed on the outer peripheral surface of the small diameter portion 25, but they are omitted in FIG. 6 (see FIG. 7). The triangular mountain serration has an action of preventing the plate and the nut from rotating relative to each other when screwing the screw into the nut (incapable of screwing).

Finally, a caulking nut shown in FIGS. 7, 8 and 9 is obtained by forming a female screw in a predetermined portion of the through hole with a tapping machine.

[0025]

According to the first aspect of the invention, the cylindrical small diameter portion 3 is arranged in the axial direction.
Large-diameter flanges 32, 52 protruding outward at the bases of 4, 54
And the cylindrical small-diameter portion 3 of the large-diameter portions 32 and 52.
Since a nut having a seating surface on the side of Nos. 4 and 54 and annular recesses 31 and 51 near the insides of the collars 32 and 52 is the main point, a highly versatile nut can be provided. Here, high versatility means that, for example, the range of adaptation to changes in plate thickness is wide. High versatility is obtained by pressing the nut against the inner wall of the hole of the plate on which the nut is to be mounted and allowing the excess thickness to flow into the annular recesses 31 and 51.

By appropriately setting the shape and volume of the annular recesses 31 and 51 provided in the nut, it is possible to realize the crimping strength according to the change of the material of the fastening material.

Further, the nut of the present invention can be manufactured by cold plastic working as described in the embodiments, and thus can be provided at a low cost.

A second aspect of the present invention is a method of mounting the nut of the first aspect of the invention on the mating members 40, 42, wherein the cylindrical small diameter portions 34, 54 are inserted into the holes of the mating members 40, 42. Since the nut mounting method is characterized in that the small diameter portions 34, 54 are pressed against the wall surface of the hole, the nut mounting method can be reliably mounted on the mating member at room temperature. When the triangular protrusion serrations are provided on the cylindrical protrusion, it can be mounted more firmly. The assembly cost for caulking can be reduced to about one-third that of welding nuts.

The present invention is not limited to the above embodiment. For example, the triangular mountain serration may not be provided and the portion may have a non-circular cross-sectional shape.

[Brief description of drawings]

1 is a cross-sectional view showing a material piece for manufacturing a nut of the present invention.

FIG. 2 is a cross-sectional view showing a molded body in the first station in the nut manufacturing process of the present invention.

FIG. 3 is a cross-sectional view showing a molded body in the second station in the nut manufacturing process of the present invention.

FIG. 4 is a cross-sectional view showing a molded body in the third station of the nut manufacturing process of the present invention.

FIG. 5 is a cross-sectional view showing a molded body at a fourth station in the nut manufacturing process of the present invention.

FIG. 6 is a cross-sectional view showing a molded body at a fifth station in the nut manufacturing process of the present invention.

FIG. 7 is a side view showing a nut according to an embodiment of the present invention, in which a cross section is taken on only one side.

FIG. 8 is a top view of the nut of FIG.

9 is an end view of the nut of FIG. 7 viewed from the seat surface side.

FIG. 10 is a cross-sectional view showing a state after the crimping of the nut of the invention.

FIG. 11 is a cross-sectional view in which the plate thickness is changed in FIG.

FIG. 12 is a side view showing a nut according to another embodiment of the present invention with a cross section taken on only one side.

[Explanation of symbols]

 34,54 Cylindrical small diameter part 32,52 Large diameter part 31,51 Annular recess ◆

Claims (2)

[Claims] 1. A large diameter portion (32, 52) protruding outward is provided at the base of the cylindrical small diameter portion (34, 54), and the cylindrical small diameter portion (34, 52) of the large diameter portion (32, 52). A nut is characterized in that a seating surface is provided on the 54) side and annular recesses (31, 51) are provided near the inside of the large diameter portions (32, 52). 2. The mating member (4) with the nut according to claim 1.
0, 42) by inserting the cylindrical small diameter portion (34, 54) into the hole of the mating member (40, 42) and pressing the cylindrical small diameter portion (34, 54). And then press this against the wall surface of the hole.