JP2002364622A - Functional parts fitting structure and functional parts fitting method for casting product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a functional parts fitting structure and a functional parts fitting method for a casting product capable of fitting the functional parts in a short time with a desirable strength, while restricting the generation of malfunction such as a crack and a breakdown. SOLUTION: In a nut 20, an annular groove 23 is formed in a fitting part 22 to be fitted to a fitting base 11, and the groove 23 is formed so that a space between the inside peripheral surface 26 and the outside peripheral surface 27 thereof is formed smaller, as it comes closer to an opening part 25 from a bottom part 24 thereof. In the fitting base 11, a top part 16 is previously formed with a cylindrical projecting part 13 having a tapered tilted part 17. The groove 23 of the nut 20 and the projecting part 13 of the fitting base 11 are fitted to each other, and the projecting part 13 is plastically deformed along the outside peripheral surface 27 of the groove 23 by caulking to fit the nut 20 to the fitting base 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a functional component mounting structure and method for fixing a functional component such as a nut to a base made of a cast product by press working or the like.

[0002]

2. Description of the Related Art Conventionally, when a female screw portion is formed on a cast product, a threading process has been performed on an inner peripheral portion of a cylindrical projection previously formed on the cast product. However, such a thread cutting process is troublesome, and there has been a problem that the processing time of a product is prolonged. In particular, in a product having many female screw portions, it is necessary to perform thread cutting while performing positioning one by one, and there is a problem that the processing time is significantly long and the manufacturing cost is high. .

[0003] In addition, at the time of the thread cutting, a processing oil must be used. Further, at the time of thread cutting, generation of chips is inevitable. On the other hand, for example, many processed products of the casting, such as airbag cases for vehicles, dislike the attachment of processing oil, chips, and the like to the products. In such a product group, it is necessary to repeatedly perform cleaning in order to almost completely remove processing oil and chips from the product after the thread cutting process. For this reason, there has been a problem that the processing time of the cast product is further increased, and the manufacturing cost is further increased.

Conventionally, as a method of quickly forming a female screw portion on a metal plate, for example, Japanese Patent Laid-Open No.
There is known a method of caulking and mounting a functional component called a pierce nut as disclosed in Japanese Patent Application Laid-Open No. 17-210 and Japanese Patent Application Laid-Open No. 8-296625.

The pierce nut has a female thread at the center of the nut body, and two cylindrical portions are formed on the lower surface of the nut body so as to surround the female thread. Among these, the side surface of the inner cylindrical portion is an inner circumferential side surface of an annular groove formed between the side surface of the female screw portion and the two cylindrical portions. On the other hand, the side surface of the outer tubular portion is the outer circumferential surface of the annular groove and the outer surface of the nut body. Of these two tubular portions, the inner tubular portion is formed such that the height from the bottom of the annular groove is increased. The outer peripheral side surface of the annular groove is inclined, and the radial width decreases from the bottom of the annular groove toward the opening. In addition, serrations extending in the vertical direction over the entire circumference are formed on the outer peripheral side surface of the annular groove.

When such a pierce nut is caulked and mounted on a metal plate, a caulking device having a lower die and a punch is used. Here, the lower mold is formed with a cylindrical convex step protruding upward from the upper surface serving as the press surface, and the inner diameter is the same as the diameter of the inner peripheral side surface of the annular groove of the pierce nut. It is almost the same size. Further, the outer diameter of the protruding step is formed so as to be smaller by a predetermined amount than the diameter of the outer peripheral side surface of the opening of the annular groove.

At the time of caulking, the nut body is driven into the metal plate set on the lower die by the punch. Thus, a punched hole is formed on the metal plate by shearing the inner cylindrical portion of the pierce nut and the lower step, and at the same time, the periphery of the punch hole is pushed out by the lower step. While being pressed into the annular groove of the pierce nut. Then, by this press-fitting, the peripheral edge of the punched hole comes into contact with the outer peripheral side surface of the annular groove, and is caulked in a state of being cut into the serration.

As described above, conventionally, the peripheral edge of the punched hole is pressed into the annular groove of the pierce nut while the peripheral edge of the punched hole of the metal plate is stretched and plastically deformed by the convex step of the lower die. I try to tighten.

[0009]

However, the conventional method of caulking and mounting a pierce nut has a small thickness, such as a sheet metal, is highly ductile, and can be easily plastically deformed.
In addition, it is suitable for those whose plastic deformation can be relatively large. However, the method cannot simply be applied to castings. That is, a cast product generally has a large thickness and poor ductility. For this reason, in a cast product, the amount of plastic deformation cannot be made large. And it is almost difficult to form a punched hole in the casting due to the shearing between the inner cylindrical portion of the pierce nut and the protruding step of the lower die, and cracks or breakage may occur around the swaged portion. There is. As described above, it has been difficult to caulk and attach the pierce nut to the cast product with the desired strength.

The present invention has been made by paying attention to such problems existing in the prior art. An object of the present invention is to provide a mounting structure and a mounting method of a functional component in a cast product, in which a functional component can be mounted in a short time while a desired strength is secured, while suppressing occurrence of a defect such as a crack or breakage. It is in.

[0011]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a structure for mounting a functional component in a cast product in which a predetermined functional component is fixed to a base made of the cast product. Wherein the functional component has a groove that forms a substantially annular shape in a plane in a mounting portion with respect to the base, and the groove is formed such that a distance between opposed side walls decreases from a bottom toward an opening. The base has a substantially cylindrical convex portion formed at a position corresponding to the groove in the mounting portion for attaching the functional component, and the convex portion is formed in a state where the groove and the convex portion are fitted. The gist is that the functional component is caulked and fixed to the base by plastically deforming along the side surface shape of the groove.

According to the first aspect of the present invention, the convex portion of the base made of a cast product formed in advance is engaged with the groove of the functional component, and the base and the functional component are formed by, for example, press working. Thereby, the convex portion is slightly plastically deformed along the inner surface shape of the groove portion. Here, the groove has a smaller opening width toward the opening, and the functional component is prevented from coming off. As a result, it is possible to easily attach the functional component to the base with a small amount of plastic deformation while maintaining the desired strength while suppressing the occurrence of defects such as cracks and breakage. In addition, since the convex portion of the base is formed simultaneously with the casting, the functional component can be engaged with the convex portion, and the functional component can be attached to the base only by press working. The manufacturing time can be shortened. Further, when the functional component is mounted on the base, the convex portion formed on the base serves as a mark, so that the mounting position of the functional component can be easily grasped.

Further, the invention described in claim 2 of the present application is characterized in that, in the invention described in claim 1, the projection has an inclined portion formed on at least a part of a top portion thereof. is there.

According to a third aspect of the present invention, in the second aspect, the inclined portion of the convex portion is formed in a tapered shape. According to the invention described in claim 2 or claim 3 of the present application, in addition to the effect of the invention described in claim 1, the top of the convex portion of the base is formed into the above-described shape, so that the top portion of the convex portion is formed. Becomes thinner. For this reason, when pressing the base and functional parts,
Even with a small pressing force, the convex portion can be easily plastically deformed with a desired strength. When the inclined portion is formed in a tapered shape, such an effect appears more remarkably.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the groove of the functional component is provided in the groove of the functional base. The main feature is that a deformation portion of the convex portion is housed in the deformation direction, and a housing portion engaging with the deformation portion is provided.

In the invention according to claim 4 of the present application, in addition to the operation of the invention according to any one of claims 1 to 3, when the base and the functional component are pressed,
When an inclined portion is provided on the top portion, the convex portion of the base undergoes plastic deformation while gradually contacting the bottom surface of the groove of the functional component from the pointed end side of the inclined portion. At that time, the deformed part of the convex part
While sliding on the bottom surface of the groove, the groove is deformed so as to warp to the accommodation portion side of the groove. For this reason, the plastic deformation of the top of the convex part by the press working of the base and the functional component becomes easy. Then, the functional component can be easily fixed to the base by the engagement between the deformed portion of the convex portion and the accommodation portion of the groove.

According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the functional component has a male component or a female component. The gist consists of:

According to the fifth aspect of the present invention, in addition to the operation of the first aspect of the present invention, an operation of threading the base is omitted. Is done. Therefore, no machining oil is required for thread cutting, and no chips are generated. As a result, a troublesome cleaning step for removing the processing oil attached to the base can be omitted, and the processing time of the product is greatly reduced.

According to a sixth aspect of the present invention, in the invention according to any one of the first to fifth aspects, at least a part of a side wall of the groove of the functional component is provided. The gist has a serration extending from the bottom of the groove toward the opening.

Here, for example, when the groove of the functional component is formed in an annular shape and the convex portion of the base is formed in a cylindrical shape, even if the functional component is mounted on the base by press working, If a large rotational torque is generated between the functional component and the functional component, the functional component may rotate relative to the base. On the other hand, according to the invention described in claim 6 of the present application, in addition to the operation of the invention described in any one of claims 1 to 5, the protrusion of the base and the groove of the functional component are provided. When the two are pressed in a state where they are engaged with each other, the convex portions are plastically deformed while biting into the serrations of the grooves. Therefore, even in the case described above, the attached functional component is suppressed from rotating relative to the base.

According to a seventh aspect of the present invention, in the first aspect of the present invention, the base is made of a light metal material. It is.

According to the seventh aspect of the present invention, in addition to the function of the first aspect, the amount of plastic deformation can be reduced while reducing the weight of the product. The functional component can be easily mounted on a base made of a small cast product having poor ductility.

Further, the invention according to claim 8 of the present application is characterized in that, in the invention according to claim 7, the light metal material is a magnesium alloy. According to the invention described in claim 8 of the present application, in addition to the effect of the invention described in claim 7, in the base made of a magnesium alloy casting that is easily cracked and is not easily plastically deformed. The effect of the invention described in any one of claims 6 is particularly effectively exerted.

According to a ninth aspect of the present invention, in accordance with the first aspect of the present invention, the base is provided in a housing of an airbag device mounted on a vehicle. The gist is to be a body.

According to the ninth aspect of the present invention, in addition to the operation of the first aspect of the present invention, it is mounted on a vehicle, and in particular, is provided with a processing oil or a chip. It is suitable for manufacturing a housing of an airbag device that does not like adhesion.

According to a tenth aspect of the present invention, there is provided a method for mounting a functional component in a cast product, wherein a predetermined functional component is fixed to a base made of the cast product. A groove that forms a substantially annular shape in the mounting part for the base,
It is formed in advance so that the distance between the opposing side walls decreases from the bottom toward the opening, and the base has a substantially cylindrical protrusion at a position corresponding to the groove at a mounting portion of the functional component. Part is formed in advance, and in a state where the groove and the convex portion are fitted, the functional component is formed on the base by plastically deforming the convex portion along the inner surface shape of the groove by press working. The gist is to fix by caulking.

According to the tenth aspect of the present invention, the same effect as that of the first aspect of the invention is exerted.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, the nut 20 as a functional component is formed of a screw component having a female screw portion 21 at the center. On the other hand, the plate-shaped mounting base 11 as a base is a part of a housing of an airbag device mounted on a steering wheel (not shown) of a vehicle (not shown), and is formed by casting a magnesium alloy material. Goods. A horn switch mechanism (not shown) is mounted on the mounting base 11, and a nut 20 is crimped to the fixing portion 12 of the mounting base 11 by a mounting method described later. First, details of the nut 20 and the mounting base 11 will be described.

The nut 20 has a flat annular groove 23 formed in a mounting portion 22 for the mounting base 11.
The groove 23 is formed so that the distance between the inner peripheral surface 26 as an opposite side wall and the outer peripheral surface 27 as the same side wall decreases from the bottom 24 toward the opening 25. Here, in the present embodiment, the groove 23 is formed on the inner peripheral surface 2.
6 is formed so as to be parallel to the reference surface of the screw hole of the female screw portion 21, while the outer peripheral surface 27 is inclined toward the inner peripheral surface 26 as the distance from the bottom 24 of the groove 23 increases. I have. The corners formed by the bottom 24 and the outer peripheral surface 27 of the groove 23 and the vicinity thereof are plastically deformed by the protrusions 13 of the mounting base 11 formed when the nut 20 is swaged to the mounting base 11. Housing part 18,
The housing portion 28 that engages with the plastic deformation portion 18 is configured.

The outer peripheral surface 27 of the groove 23 has a direction A from the bottom 24 to the opening 25 over the entire periphery.
A first serration 29 extending to (see FIG. 1) is formed. Further, a second serration 31 extending in the radial direction of the top surface over the entire circumference is provided on the top surface of the cylindrical portion 30 having the outer surface 20a of the nut 20 and the outer peripheral surface 27 of the groove 23 as side surfaces. Is formed.

On the other hand, the mounting base 11 is provided with a cylindrical projection 13 on the fixing portion 12 to which the nut 20 is fixed.
It is formed in advance at a position corresponding to the groove 23 of 0. The diameter of the inner peripheral surface 14 of the convex portion 13 is substantially the same as the diameter of the inner peripheral surface 26 of the groove 23, and the diameter of the outer peripheral surface 15 of the convex portion 13 is the opening of the groove 23. 25 is formed so as to have substantially the same diameter as the diameter of the outer peripheral surface 27. The projection 13 is formed simultaneously with the casting of the mounting base 11. The convex portion 13 has a tapered inclined portion 17 formed over the entire top portion 16. Here, in the present embodiment, the inclined portion 17 is formed so that the height from the outer surface 11 a of the mounting base 11 becomes smaller as going from the outer peripheral surface 15 of the convex portion 13 to the inner peripheral surface 14. The outer peripheral surface 15 and the inclined portion 17 of the convex portion 13
When the nut 20 is crimped to the mounting base 11, the corner portion formed by
8, and constitutes the plastic deformation portion 18 that engages with the accommodation portion 28.

When the nut 20 having the above configuration is mounted on the mounting base 11, the following procedure is performed, for example. As shown in FIG. 2, the groove 23 of the nut 20 in which the groove 23 is formed in the above-described shape in advance, and the protrusion 13 of the mounting base 11 in which the protrusion 13 having the inclined portion 17 is formed in advance.
And are fitted. Then, with the groove 23 of the nut 20 and the projection 13 of the mounting base 11 being fitted, the mounting base 11
Is set on the die 40 of the press device (see FIG. 2), and then the punch 41 of the press device (see FIG. 2) is
, And the mounting base 11 and the nut 20 are pressed.

By this press working, the top 16 of the projection 13 of the mounting base 11 gradually comes into contact with the bottom 24 of the groove 23 of the nut 20 from the pointed end of the tip, and plastically deforms. At this time, the plastic deformation portion 18 of the convex portion 13 of the mounting base 11 slides on the bottom 24 of the groove 23 of the nut 20 while being plastically deformed so as to be accommodated in the accommodation portion 28 of the groove 23. I do. Then, the protrusion 13 of the mounting base 11 is plastically deformed along the inclined shape of the outer peripheral surface 27 of the groove 23 of the nut 20 and bites into the first serration 29, and the nut 20 is mounted on the mounting base 11. 11 is crimped. At this time, the second serrations 31 of the nut 20 come into contact with the outer surface 11 a of the mounting base 11 and bite into the mounting base 11.

Therefore, according to the present embodiment, the following effects can be obtained. (1) In the present embodiment, the inner peripheral surface 26 is provided on the nut 20 as the outer peripheral surface 27 moves from the bottom 24 to the opening 25.
The groove 23 inclined so as to approach the side was formed in advance.
Then, in a state where the groove 23 of the nut 20 and the convex portion 13 formed in advance on the mounting base 11 are fitted, the mounting base 11
And the nut 20 were pressed, and the convex portion 13 was plastically deformed along the shape of the outer peripheral surface 27 of the groove 23. As a result, the projection 13 of the mounting base 11 comes into contact with the outer peripheral surface 27 of the nut 20 and is plastically deformed. For this reason,
The nut 20 can be swaged in a state in which the nut 20 is prevented from falling out of the mounting base 11. Further, the nut 20 can be easily mounted on the mounting base 11 with a desired amount of plastic deformation while suppressing the occurrence of defects such as cracks and breaks with a small amount of plastic deformation.

The projection 13 of the mounting base 11 is formed at the same time as casting.
The nut 20 can be mounted on the mounting base 11 only by engaging the groove 23 of 0 and pressing. For this reason, the manufacturing time of a product can be reduced.

When the nut 20 is mounted on the mounting base 11, the protrusion 13 formed on the mounting base 11 serves as a mark, so that the mounting position of the nut 20 can be easily grasped and the nut 20 can be easily grasped. Can be easily positioned.

(2) In this embodiment, a tapered inclined portion 17 is formed on the entire top 16 of the projection 13 of the mounting base 11. For this reason, the top part 16 of the convex part 13 becomes thin, and when pressing the mounting base 11 and the nut 20, the convex part 13 is easily plastically deformed so as to have a desired fastening strength even with a small pressing force. Can be.

(3) In the present embodiment, the groove 2 of the nut 20
In the corner portion formed by the bottom portion 24 and the outer peripheral surface 27 and the vicinity thereof, the plastic deformation portion 18 of the convex portion 13 of the mounting base 11 is housed and the housing portion engaging with the plastic deformation portion 18 28 were provided. Therefore, the nut 20 can be easily fixed to the mounting base 11 by the engagement between the plastic deformation portion 18 of the convex portion 13 of the mounting base 11 and the housing portion 28 of the groove 23 of the nut 20. .

(4) In the present embodiment, the nut 20 is made of a screw component having the female screw portion 21.
Thereby, the work of performing thread cutting on the mounting base 11 can be omitted. Therefore, processing oil is not required for forming the female screw portion 21, and generation of chips can be eliminated. As a result, the mounting base 1
A troublesome cleaning step for removing the processing oil and chips attached to 1 can be omitted, and the processing time of the product can be greatly reduced.

(5) In the present embodiment, the groove 2 of the nut 20
The first serration 29 is provided on the entire outer peripheral surface 27 of
Further, a second serration 31 is provided on the entire circumference of the top surface of the cylindrical portion 30.
Was formed. For this reason, even if rotational torque acts between the mounting base 11 and the nut 20, it is possible to suppress the crimped nut 20 from rotating relative to the mounting base 11.

(6) In the present embodiment, the mounting base 11 is made of a casting made of a magnesium alloy. For this reason, even in the case of a magnesium alloy casting product in which cracks are easily generated and plastic deformation is difficult, the effects described in the above (1) to (5) are remarkably exhibited, in addition to the fact that the product can be reduced in weight. It is suitable.

(7) In this embodiment, the mounting base 11 is
The housing of the airbag device mounted on the vehicle was used. For this reason, it can be made suitable for manufacturing a housing of an airbag device which is mounted on a vehicle and which is particularly resistant to the attachment of processing oil and chips.

(Modification) The embodiment of the present invention may be modified as follows. In the above-described embodiment, at least one of the first serration 29 and the second serration 31 of the nut 20 may be formed on a part of a surface to be formed.

In the above embodiment, a configuration may be adopted in which an inclined portion is formed in at least a part of the bottom 24 of the groove 23 of the nut 20. In the embodiment, only the outer peripheral surface 27 of the groove 23 of the nut 20 is inclined. However, for example, as shown in FIG. 3, only the inner peripheral surface 26 of the groove 23 may be inclined. In this case, the first serration 29 is formed on the inner peripheral surface 26, while
It is desirable that the convex portion 13 of the mounting base 11 be formed so that the plastic deformation portion 18 is accommodated in an accommodation portion 28 formed by the bottom portion 24 of the groove 23 of the nut 20 and the inner peripheral surface 26.

In the above-described embodiment, the groove 23 of the nut 20 is formed in a plane circular shape, but the plane shape of the groove 23 is not limited to a circular shape. The groove 23 may be formed in, for example, a plane ellipse or a plane polygon.
In addition, the groove 23 may be formed so as to be interrupted at one or a plurality of places, instead of being annular in a plane. The groove 2
3 is formed in this manner, the projection 1 of the mounting base 11
3 is formed according to the planar shape of the groove 23. Also,
The convex portion 13 may be formed so as to be interrupted at one or a plurality of positions with respect to the planar annular groove 23.

When the groove 23 of the nut 20 and the projection 13 of the mounting base 11 are formed in a plane polygon,
For example, as shown in FIG. 4, any one of the inner surface 35 and the outer surface 36 of each side in the planar shape of the groove 23 of the nut 20 may be configured to be inclined. In this case, the plastic deformation portion 18 of the projection 13 of the mounting base 11
Is desirably formed so as to correspond to the accommodation portion 28 of the groove 23.

When the groove 23 of the nut 20 and the projection 13 of the mounting base 11 are formed in, for example, a plane ellipse, a plane polygon, or the like, the first outer peripheral surface 27 of the groove 23 has the first shape. The configuration may be such that the serrations 29 are omitted.

In the above embodiment, the nut 2
When the top of the cylindrical portion 30 is caulked so as to be separated from the outer surface 11a of the mounting base 11, the second serration 31 of the nut 20 may be omitted.

In the above embodiment, the nut 2
Both the inner peripheral surface 26 and the outer peripheral surface 27 of the groove 23
A configuration in which the space between the two peripheral surfaces 26 and 27 becomes smaller from the bottom 24 toward the opening 25 may be adopted.
In this case, the first serration 29 may be formed on at least one of the inner peripheral surface 26 and the outer peripheral surface 27.

In the above embodiment, the nut 2
Instead of 0, for example, a configuration using a screw component having an external thread portion such as a bolt may be used. In the above-described embodiment, the example of the mounting base 11 formed in a plate shape has been described, but the mounting base 11 is not limited to the plate shape. The mounting base 11 may have, for example, a block shape or the like.

In the above embodiment, the mounting base 11
Was a cast product made of magnesium alloy.
The material of 1 is optional. When the mounting base 11 is a cast product, the present invention can be similarly applied. If the mounting base 11 is a cast product of a light metal material such as an aluminum alloy, for example, the weight of the product is reduced, and the mounting base 11 is made of a cast product with a small plastic deformation and poor ductility. 20 can be easily attached.

Also, in the above embodiment, the mounting base 11
Although the top 16 of the projection 13 is formed in a tapered shape, the shape of the top 16 is not limited to the tapered shape.
The top portion 16 may be formed to have, for example, two or more inclined portions, or may have an inclined portion having a concave or convex curved surface.

Also, in the above embodiment, the top 16 of the projection 13 has an inclined portion 17 as a whole.
However, a configuration in which the inclined portion 17 is provided in a part of the crest 16 may be adopted. Further, a configuration in which the inclined portion 17 is not formed on the top portion 16 of the convex portion 13 may be adopted.

Also, in the above embodiment, the mounting base 11
Is a housing of an airbag device mounted on a vehicle. However, the present invention is similarly applied to any case made of a cast product such as a core metal of a steering wheel of a vehicle, a cylinder block or a cylinder head of an internal combustion engine, a housing of a camera, and a housing of a personal computer. be able to.

[0055]

As described above in detail, according to the first, fourth or tenth aspect of the present invention, the occurrence of defects such as cracks and breaks can be suppressed with a small amount of plastic deformation. In addition, the functional component can be easily attached to the base with the desired strength secured. In addition, it is possible to reduce the manufacturing time of the product. Further, the mounting position of the functional component can be easily grasped.

According to the second or third aspect of the present invention, in addition to the effect of the first aspect, a small pressing force is applied when the base and the functional component are pressed. However, the convex portion can be easily plastically deformed with a desired strength.

According to the invention as set forth in claim 5 of the present application, in addition to the effects of the invention as set forth in any one of claims 1 to 4, a threading process is performed on the base. Work can be omitted. Further, a troublesome cleaning step for removing processing oil and chips attached to the base can be omitted, and the processing time of the product can be greatly reduced.

According to the invention of claim 6 of the present application, in addition to the effects of the invention of any one of claims 1 to 5, the groove of the functional component and the protrusion of the base are provided. Even when the portion is formed in an annular shape, it is possible to suppress the attached functional component from rotating relative to the base.

According to the invention of claim 7 of the present application, in addition to the effect of the invention of any one of claims 1 to 6, it is possible to reduce the weight of the product, The functional component can be easily mounted on a base made of a cast product having a small deformation and poor ductility.

According to the invention as set forth in claim 8 of the present application, in addition to the effects of the invention as set forth in claim 7, in addition to a base made of a magnesium alloy casting that is easily cracked and hardly deformed plastically. The effects of the invention according to any one of claims 1 to 6 can be particularly remarkably exhibited.

According to the invention as set forth in claim 9 of the present application, in addition to the effects of the invention as set forth in any one of claims 1 to 8, it is mounted on a vehicle, and in particular, a processing oil or It is suitable for manufacturing a housing of an airbag device that does not like the attachment of chips.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a mounting base and a nut before swaging according to an embodiment.

FIG. 2 is a cross-sectional view of the mounting base and the nut after crimping.

FIG. 3 is a sectional view of a mounting base and a nut before swaging in a modified example.

FIG. 4 is a cross-sectional view of a mounting base and a nut before swaging in a modified example.

[Explanation of symbols]

11: Mounting base as a base made of a cast product, 13: Projection, 16: Top, 17: Inclined part, 18: Plastic deformation part as deformation part, 20: Nut as functional part, 21: Female screw part , 22 ... mounting part, 23 ... groove, 24 ... bottom part, 25 ...
Opening 26, inner peripheral surface as side wall, 27 outer peripheral surface as side wall, accommodation part 29, first serration as serration.

Claims (10)

[Claims] 1. A mounting structure of a functional component in a cast product for fixing a predetermined functional component to a base made of a cast product, wherein the functional component has a groove formed in a substantially annular shape on a mounting portion with respect to the base. The groove is formed so that the distance between the opposing side walls decreases from the bottom toward the opening, and the base is located at a position corresponding to the groove in the mounting portion for mounting the functional component. A substantially cylindrical projection is formed,
A casting wherein the functional component is caulked to the base by being plastically deformed along the side surface shape of the groove in a state where the groove and the convex portion are fitted to each other, and fixed. Mounting structure of functional parts in 2. The mounting structure for a functional part in a cast product according to claim 1, wherein an inclined portion is formed on at least a part of a top portion of said convex portion. 3. The mounting structure for a functional part in a cast product according to claim 2, wherein the inclined portion of said convex portion is formed in a tapered shape. 4. A groove for accommodating a deformed portion of the protrusion in the groove of the functional component in a direction of deformation of the protrusion of the base, and an accommodating portion engaging with the deformed portion is provided. A mounting structure for a functional component in a cast product according to any one of claims 1 to 3, characterized in that: 5. The mounting of a functional component in a casting according to claim 1, wherein the functional component comprises a screw component having a male thread or a female thread. Construction. 6. The functional component according to claim 1, wherein at least a part of a side wall of the groove of the functional component has a serration extending from the bottom of the groove toward the opening. A mounting structure for a functional component in the casting according to any one of the preceding claims. 7. The mounting structure for a functional part in a cast product according to claim 1, wherein the base is made of a light metal material. 8. The structure according to claim 7, wherein the light metal material is a magnesium alloy. 9. The air conditioner according to claim 1, wherein the base is a housing of an airbag device mounted on a vehicle.
A mounting structure for a functional component in a cast product according to any one of the above. 10. A method of mounting a functional component in a cast product, wherein a predetermined functional component is fixed to a base made of a cast product, wherein the functional component has a substantially annular shape in a mounting portion with respect to the base. Grooves are formed in advance so that the distance between the side wall portions facing each other decreases from the bottom toward the opening, and the base has a substantially cylindrical portion at a position corresponding to the groove at a mounting portion for the functional component. The functional component is formed by forming a convex portion in advance and plastically deforming the convex portion along the inner surface shape of the groove by press working in a state where the groove and the convex portion are fitted. A method for mounting a functional component in a cast product, wherein the functional component is fixed by caulking to a base.