JP2003003842A - Outer component of exhaust system and production method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an outer component having small diameter connection openings on both ends thereof by an inexpensive press die method without adopting an expensive spinning method. SOLUTION: This outer component comprises a first component part 3 in which one end of a cylindrical body 3b is opened in a large diameter same as that thereof and the other end is narrowed down by a press working to form a connection opening 3e, and a second component part 4 having a connection opening 4c narrowed down by the press working. The second component part 4 is joined and fixed to the large opening 3a of the first component part 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outer part used in an exhaust system of an internal combustion engine and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, outer parts (outer shell) of a purifying device or a muffler provided in an exhaust system of an internal combustion engine for automobiles.
In order to connect the exhaust pipe to the front and rear ends thereof, a small-diameter connection port is formed in the front and rear.

Therefore, conventionally, two plates 104 and 10 having a cylindrical or elliptic cylindrical main body 101 as shown in FIG. 3A and connection ports 102 and 103 having small diameters are formed.
It is known to use No. 5 and to join them by the curl seam method as shown in FIG. Note that FIG.
In (b), 106 and 107 denote curl seam portions.

Further, a cylindrical or elliptic cylindrical metal element pipe 201 as shown in FIG. 4A is used, and both ends in the axial direction of the pipe 201 are spatula 202 as shown in FIG. 4B. Is reduced by a spinning method (spatula drawing method) that moves the tube 201 in the axial direction and the radial direction of the tube 201, and the tapered portions 203, 2
It is also known to form connection ports 205 and 206 having a small diameter with 04.

[0005]

In the conventional outer part shown in FIG. 3, the outer part is composed of three parts, and
There is a problem in productivity because it requires curl seam processing at some locations.

In the case of forming an outer part by spinning as shown in FIG. 4, there is a problem that the mechanism becomes expensive because it is necessary to incorporate a special function into the spinning machine. .

[0007] Therefore, an object of the present invention is to provide an outer part of an exhaust system which can be constituted by two parts and can be molded by a press machine which is cheaper than a spinning machine, and a manufacturing method thereof. is there.

[0008]

In order to solve the above-mentioned problems, the first invention according to claim 1 is such that one end of a cylindrical main body portion is opened with a large diameter equal to that of the main body portion, It is composed of a first part having a small-diameter connection port that is narrowed by pressing at the end and a second part that has a small-diameter connection port that is narrowed by pressing, and at the large-diameter side opening of the first part. It is an outer component for an exhaust system, characterized in that the second component is bonded and fixed.

A second aspect of the present invention is the method for manufacturing an outer part according to the first aspect of the present invention, wherein one end of the tubular main body portion is opened with a large diameter equal to that of the main body portion, and the other end is formed. The first part having a small-diameter connection port in its part is press-formed from a cylindrical metal tube, and the second part having a small-diameter connection port is press-formed from a metal plate. A method of manufacturing an outer component of an exhaust system, characterized in that the second component is bonded and fixed to a radial opening.

According to a third aspect of the present invention, one end of the tubular main body portion has a large diameter equal to that of the main body portion, and the other end portion has a small-diameter connection port narrowed by press working. A first part and a second part having the same shape as the first part, and the first part and the second part are joined and connected to each other at their large diameter side openings. It is the outer part of the exhaust system.

A fourth aspect of the present invention is the method of manufacturing an outer part according to the third aspect of the present invention, wherein one end of the tubular main body portion has a large diameter equal to that of the main body portion, and the other end. The first part having a small-diameter connection port is formed by press working, and the second part having the same shape as the first part is separately formed by press working, and these are joined to each other at their large diameter side openings. And a method of manufacturing an outer component of an exhaust system, which is characterized in that the outer components are connected.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described based on the embodiments shown in FIGS.

FIG. 1 shows a first embodiment.

In the first embodiment, first, as shown in FIG. 1A, a metallic cylindrical material 1 and a metallic plate material 2 are prepared.

Next, the tubular material 1 is drawn by a pressing machine into the shape of the first part 3 shown in FIG. 1 (b). That is, the diameter of one opening 3a is made the same as the diameter of the main portion 3b, and the other end is drawn by a press die to reduce the diameter, and the tapered portion 3c and the connection opening 3d having a small diameter are formed. The reduced diameter portion 3e is formed. The main body 3b is formed in a cylindrical shape or an elliptic cylinder, and the connection port 3d is formed in a cylindrical shape.

During this press molding, the first part 3
The opening diameter of the one opening 3a is set to the main body 3 of the first component 3.
Since the diameter is not made smaller than the diameter of b, the mold can be easily attached to and detached from the opening 3a in the pressing machine, and the main body portion 3b and the other reduced diameter portion 3e can also be formed by drawing. Even when the reduced diameter portion 3e is tilted with respect to the axis of the main body portion 3b as shown in FIG. 1 (b), it can be formed by pressing with a cam slide die.
Further, a joining piece 3f is bent outward by press molding on one opening 3a side of the first component 3.

Further, the plate-shaped material 2 is also drawn by a press into the shape of the second part 4 shown in FIG. 1 (b). That is, the opening 4a is formed from the plate-shaped material 2 to have a diameter substantially the same as that of the main body 3b by pressing, and the reduced diameter portion 4d including the tapered portion 4b and the connection port 4c is also pressed. Even in this case, with the cam slide mold,
As shown in FIG. 1 (b), an inclined reduced diameter portion 4d can be formed. Further, the outer peripheral portion of the plate-shaped material 2 is used as a joining piece 4e.

As described above, since the tapered portions 3c and 4b are formed by drawing using a press, the tapered portions 3c and 4 are formed.
b can be formed at a large angle with respect to the axis of the main body 3b,
The area occupied by the taper portions 3c and 4b can be minimized.

Next, the joining piece 3f of the first part 3 and the joining piece 4e of the second part 4 which have been press-molded as described above are polymerized, and these are curled by a curl seam machine.
The two parts 3 and 4 are joined as shown in FIG. Figure 1
In (c), 5 indicates the curl seam portion.

The two parts 3 and 4 may be joined by welding.

FIG. 2 shows a second embodiment.

In the second embodiment, first, a metal first tubular material 6 and a second tubular material 7 as shown in FIG. 2A are prepared. The two materials 6 and 7 have the same shape.

Next, the first tubular material 6 is drawn by a pressing machine into the shape of the first part 8 shown in FIG. 2 (b). That is, the diameter of one opening 8a is made the same as the diameter of the main body 8b, and the other end is drawn by a press die to reduce the diameter, and the reduced diameter portion 8e including the tapered portion 8c and the connection port 8d. To mold. The main body 8b is formed in a cylindrical shape or an elliptic cylinder, and the connection port 8d is formed in a cylindrical shape. At the time of this press molding, since the opening diameter of one opening 8a of the first component 8 is not made smaller than the diameter of the main body portion 8b of the first component 8, mounting of the mold in the pressing machine from this opening 8a. , The mold can be easily removed, and the main body portion 8b and the other reduced diameter portion 8
e can also be formed by drawing with a press. Also,
The axis of the connection port 8d is closer to that of the main body 8b than the axis of the main body 8b.
Even if it is eccentric α as in (b), this connection port 8d can be easily formed by pressing. Further, a joining piece 8f is bent outward by press molding on one opening 8a side of the first component 8.

The second tubular material 7 shown in FIG.
Is drawn by a pressing machine in the same manner as the first tubular material 6 to form a second part 9 shown in FIG. 1 (b). The shape of the second part 9 is the same as the shape of the first part 8. In this second part 9, 9a is the same opening as 8a, 9b is the same main part as 8b, and 9c is the same. 8
A tapered portion similar to c, 9d is a connection opening similar to 8d,
9e is a reduced diameter portion similar to 8e, and 9f is a joining piece similar to 8f.

Also in the second embodiment, the reduced diameter portions 8e and 9e are provided.
Is formed by drawing using a press, the tapered portions 8c and 9c can be formed at a large angle with respect to the axis of the main body portions 8b and 9b, and the occupied area of the portion formed by the tapered portions 8c and 9c is the minimum required. Can be limited.

Next, the first and the second parts 8 and 9f of the first part 8 and the second part 9 press-molded as described above are polymerized and curled by a curl seam machine, as shown in FIG. 2 (c). The two parts are joined together as described above. 1 in FIG. 2 (c)
0 indicates the curl seam portion.

The two parts 8 and 9 may be joined by welding.

In the case of press-molding as in the present invention, if the main body portions 3b, 8b, 9b are too long in the axial direction, there are problems such as mounting and demolding of the press die.
When the axial length of the formed outer component is as short as about 200 mm, the structure and manufacturing method of the first embodiment shown in FIG. 1 is adopted, and when it is longer than 200 mm, the structure shown in FIG.
It is desirable to adopt the structure and the manufacturing method thereof according to the second embodiment shown in FIG.

According to the second embodiment, the first
The parts 8 and the second part 9 can have the same shape, and in that case, there is a feature that the press dies of the first part 8 and the second part 9 can be shared.

The outer part of the present invention is used as an outer part (outer shell) of a purifying device, a muffler or the like provided in the exhaust system of an internal combustion engine.

[0031]

As described above, according to the present invention, since the outer part having the small-diameter connection ports at both ends can be composed of two parts, the conventional three parts shown in FIG. Productivity is better than that.

Further, since the outer part can be formed by a drawing process using a press, that is, a press die system without adopting the conventional spinning process system as shown in FIG. 4, the machine is less expensive than a spinning machine. Can be molded with.

Furthermore, a connection port that is inclined or eccentric with respect to the axis of the main body can also be formed by pressing.

Further, the angle of the taper portion required for forming the connection port, that is, the angle of the taper portion with respect to the axis of the main body can be made larger than that in the spinning method, so that this taper portion is formed. The occupied portion can be formed to a necessary minimum as compared with the spinning method, and a large internal volume required by the device using the outer component can be secured.

Further, since the press die system is used, it is possible to reduce the degree of occurrence of defects in the working process.

[Brief description of drawings]

1A and 1B show a first embodiment of the present invention, in which FIG. 1A is a side sectional view showing a material, FIG. 1B is a side sectional view showing two parts press-molded from the material of FIG. ) Is a side cross-sectional view of the outer part in which the part (b) is assembled.

2A and 2B show a second embodiment of the present invention, in which FIG. 2A is a side sectional view showing a material, FIG. 2B is a side sectional view showing two parts press-formed from the material of FIG. ) Is a side cross-sectional view of the outer part in which the part (b) is assembled.

3A and 3B show a conventional outer part, wherein FIG. 3A is a side sectional view showing components, and FIG. 3B is a side sectional view of an outer part in which the parts shown in FIG.

FIG. 4 shows another conventional outer part, (a)
Is a side sectional view of the material, and (b) is a side sectional view of the outer part formed by the spinning process.

[Explanation of symbols]

1,2,6,7 material 3,8 First part 4,9 Second part 3a, 4a, 8a, 9a openings 3b, 8b, 9b Main part 3c, 4b, 8c, 9c Tapered part 3d, 4c, 8d, 9d connection port 3e, 4d, 8e, 9e Reduced diameter part

Claims (4)

[Claims] 1. A first component having one end of a tubular main body having a large diameter equal to that of the main body and having a small-diameter connection port narrowed at the other end by press working, and the first component being pressed by press working. And a second component having a small-diameter connection port, wherein the second component is joined and fixed to the large-diameter side opening of the first component. 2. A first component having one end of a tubular main body having a large diameter equal to that of the main body and having a small-diameter connection port at the other end is formed by press working from a tubular metal tube. , A second part having a small-diameter connection port is separately formed by pressing from a metal plate,
A method for manufacturing an outer component of an exhaust system, comprising bonding and fixing the second component to the large-diameter side opening of the first component. 3. A first component having a tubular main body having one end having a large diameter equal to that of the main body and having a small-diameter connection port narrowed by press working at the other end, and the first component. The same shape as the second
An outer component of an exhaust system, which is composed of a component, and the first component and the second component are joined and connected to each other at respective large diameter side openings. 4. A first part having a large-diameter opening having the same diameter as that of the main part and one end having a small-diameter connection opening at the other end of the tubular main part is formed by press working, and the first part is separately provided. A method of manufacturing an outer component of an exhaust system, characterized in that a second component having the same shape as the above is molded by press working, and these are joined and connected to each other at their respective large-diameter side openings.