JP3451587B2 - Pipe connection structure to silencer and method of connection - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silencer pipe connecting structure for connecting a pipe member to a muffler pipe of the silencer, and a connecting method thereof.

[0002]

2. Description of the Related Art Recently, in automobiles, exhaust pipes have been made thinner in order to reduce weight and cost.
As for the connecting portion of the exhaust pipe to the muffler pipe of the silencer, there is a demand for a connecting structure that does not use welding because of the difficulty of arc welding due to the thinning of the exhaust pipe.

Conventionally, as a pipe connection structure to a muffler which does not use welding as described above, for example, an actual open flat wire 4-1059 is used.
A connection structure as disclosed in Japanese Patent No. 33 is known. FIG. 7 shows a pipe connection structure to the silencer disclosed in this publication. In this connection structure, a slit 13a is formed at an end of the muffler pipe 13 of the silencer 11 at a predetermined angle. The exhaust pipe 15 is inserted at the end.

On the outside of the muffler pipe 13, a pair of semicircular tightening bands 17 are arranged.
In the state in which the batch member 15a fixed to the outer periphery of the exhaust pipe 15 is fitted in the fitting hole 17a formed in 7, the pair of tightening bands 17 is tightened by the bolt 19 and the nut 20, so that the muffler pipe 13 The exhaust pipe 15 is fixed to the.

In the pipe connection structure to such a muffler, since the muffler pipe 13 and the exhaust pipe 15 are connected by the pair of tightening bands 17, welding can be made unnecessary.

[0006]

However, in such a conventional pipe connecting structure to a muffler, since the muffler pipe 13 and the exhaust pipe 15 are connected by the pair of tightening bands 17, the number of parts is reduced. However, there is a problem in that a large number of assembling steps are required.

Further, there is a possibility that the tightening force becomes small at the joint between the pair of tightening bands 17 and in the vicinity thereof, resulting in poor sealing. The present invention has been made in order to solve such a conventional problem, and an object thereof is to provide a connecting structure of a pipe body and a connecting method thereof, which can greatly improve the sealability with a simple structure as compared with the conventional structure. To do.

[0008]

According to a pipe connecting structure for a muffler of claim 1, a pipe member is connected to a projecting portion of a muffler pipe projecting outward from a through hole formed in an end plate of the muffler. In the pipe connection structure to the silencer for
While forming a burring portion protruding outward along the peripheral edge of the through hole of the end plate of the silencer, forming an annular projection protruding outward along the outer periphery of the burring portion,
The pipe member is plastically deformed and fitted to the outer periphery of the annular projection of the burring portion.

A method of connecting a pipe to the silencer according to claim 2 is
A pipe connecting method to a silencer for connecting a pipe member to a projecting portion of a muffler pipe protruding outward from a through hole formed in an end plate of the silencer, wherein the through hole of the end plate of the silencer is provided. After fitting the pipe member to the outer periphery of the burring portion formed to project outward along the peripheral edge of, the muffler pipe, the burring portion and the overlapping portion of the pipe member are plastically deformed by bulging, and the muffler pipe,
It is characterized in that an annular protrusion protruding outward along the outer periphery of the burring portion and the pipe member is formed in a superposed state.

A pipe connecting method to the silencer according to claim 3 is as follows:
In a pipe connecting method to a muffler for connecting a pipe member to a projecting portion of a muffler pipe protruding outward from a through hole formed in an end plate of the muffler, a pipe member is fitted to an outer periphery of the muffler pipe. And abutting the end surface of the pipe member to the end surface of the burring portion formed to project outward along the peripheral edge of the through hole of the end plate of the silencer, and then abutting the burring portion and the pipe member. A fitting member is fitted on the outer periphery of the pipe, and the muffler pipe, the burring portion, the pipe member and the connecting member are plastically deformed by bulging at the butting portion of the burring portion and the pipe member, It is characterized in that an annular protrusion protruding outward along the outer periphery of the connecting member is formed in a superposed state.

A method of connecting a pipe to the silencer according to claim 4 is
A pipe connecting method to a silencer for connecting a pipe member to a projecting portion of a muffler pipe protruding outward from a through hole formed in an end plate of the silencer, wherein the through hole of the end plate of the silencer is provided. After forming an annular protrusion that protrudes outward along the outer periphery of the burring portion that is formed to protrude outward along the peripheral edge of the The expanded diameter portion is plastically deformed, and the expanded diameter portion of the pipe member is fitted to the annular protrusion of the burring portion.

(Operation) In the pipe connecting structure to the muffler according to the first aspect, the annular protrusion protruding outward is formed along the outer periphery of the burring portion,
The pipe member is plastically deformed and fitted on the outer periphery of the annular protrusion of the burring portion. In the method of connecting the pipe to the muffler of the second aspect, the muffler pipe, the burring portion, and the annular projection protruding outward along the outer circumference of the pipe member are formed in a superposed state by bulging.

In the pipe connecting method to the muffler according to the third aspect of the present invention, the muffler pipe, the burring portion, the annular member protruding outward along the outer circumferences of the pipe member and the connecting member are formed in a superposed state by bulging. It In the method of connecting a pipe to a silencer according to a fourth aspect, the expanded diameter portion of the pipe member is plastically deformed, and the expanded diameter portion of the pipe member is fitted to the annular protrusion of the burring portion.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the embodiments shown in the drawings. FIG. 1 shows a first embodiment of a pipe connecting method to a muffler of the present invention. In the figure, reference numeral 21 denotes an elliptic cylindrical muffler body forming a muffler 23.

An end plate 25 is wound around the opening of the silencer body 21 to form a wound portion 27. End plate 2
5 is made of stainless steel, for example, 0.6 to 1.2
The thickness is about mm. The end plate 25 has a through hole 25.
a is formed, and the muffler pipe 29 is formed in the through hole 25a.
Has been inserted.

The muffler pipe 29 is made of stainless steel and has a wall thickness of, for example, about 0.3 to 1.0 mm. A burring portion 31 protruding outward is formed on the peripheral edge of the through hole 25a. A pipe member 33 forming an exhaust pipe is fitted around the burring portion 31.

The pipe member 33 is made of stainless steel and has a wall thickness of, for example, about 0.8 mm. Further, annular projections 29a, 31a, 33a protruding outward along the outer periphery are formed in a superposed state at the superposed portions of the muffler pipe 29, the burring portion 31 and the pipe member 33.

The muffler pipe 29 of the silencer 23 described above
The pipe member 33 is connected to the pipe member 33 as described below. First, as shown in FIG. 2A, the pipe member 33 is fitted around the outer periphery of the burring portion 31.

Next, as shown in (b), the pipe member 3
The die member 35 is fitted on the outer periphery of the muffler pipe 2
The bulge processing device 37 is inserted into the inner circumference of 9. An annular recess 35a having an arcuate cross section is formed on the inner circumference of the die member 35. The bulge processing device 37 has a muffler pipe 29.
It has a urethane member 39 which is inserted into.

At the center of the urethane member 39, there is a rod member 41.
And the plate 43 is fixed to the tip of the rod member 41. The urethane member 39 is fixed to the tip of the support member 45 inserted into the pipe member 33. Bar member 4
1 and the rear end of the support member 45 are pulled out from the pipe member 33.

When the rod member 41 is pulled from this state as shown in (c), the urethane member 39 causes the muffler pipe 29, the burring portion 31, and the pipe member 33 to face the annular recess 35a of the die member 35. Plastic deformation of the muffler pipe 29, the burring portion 31 and the pipe member 33, and annular protrusions 29a, 31a, 33a protruding outward are formed in a superposed state.

In the pipe connection structure to the silencer described above,
The pipe member 33 is fitted to the outer circumference of the burring portion 31, and the ring-shaped projections 29a, 3 projecting outward along the outer circumferences of the muffler pipe 29, the burring portion 31, and the pipe member 33.
Since 1a and 33a are formed in a polymerized state, the sealing property can be greatly improved with a simple structure as compared with the conventional case. Further, in the pipe connecting method to the silencer described above, the annular projections 29a, 31a, 33a protruding outward along the outer circumferences of the muffler pipe 29, the burring portion 31, and the pipe member 33 are overlapped by bulging. Since it is formed, the pipe connection structure to the silencer described above is easy,
You can definitely get it.

FIG. 3 shows a second embodiment of the pipe connecting method to the muffler of the present invention. In this embodiment,
The projecting length of the muffler pipe 29 is made longer than the projecting length of the burring portion 31, and the pipe member 33 is fitted to the outer periphery of the muffler pipe 29. Further, a connecting member 47 is fitted around the outer periphery of the butt portion of the burring portion 31 and the pipe member 33.

The connecting member 47 is made of stainless steel and has a wall thickness of, for example, about 0.1 to 0.4 mm. The muffler pipe 29 and the burring portion 3 are provided at the abutting portion of the burring portion 31 and the pipe member 33.
1, annular protrusions 29b, 31b, 33b, 47 protruding outward along the outer peripheries of the pipe member 33 and the connecting member 47
b is formed in a polymerized state.

The muffler pipe 29 of the silencer 23 described above
The pipe member 33 is connected to the pipe member 33 as described below. First, as shown in FIG. 4A, a pipe member 33 is fitted on the outer periphery of the muffler pipe 29, the end surface of the pipe member 33 is brought into contact with the end surface of the burring portion 31, and the burring portion 31 and The connecting member 47 is fitted on the outer periphery of the butted portion of the pipe member 33.

Next, as shown in FIG.
The die member 35 is fitted on the outer periphery of the muffler pipe 29.
The bulge processing device 37 is inserted into the inner circumference of the. Then, when the rod member 41 is pulled from this state, as shown in (c), the muffler pipe 29, the burring portion 31, the pipe member 33, and the connecting member 47 are caused by the urethane member 39.
Is plastically deformed toward the annular recess 35a of the die member 35, and protrudes outward along the outer peripheries of the muffler pipe 29, the burring portion 31, the pipe member 33 and the connecting member 47, and the annular protrusions 29b, 31b, 33b, 47b is formed in a polymerized state.

In the pipe connecting structure to the muffler of the second embodiment, the connecting member 47 is fitted on the outer periphery of the abutting portion of the burring portion 31 and the pipe member 33, and the abutting portion of the burring portion 31 and the pipe member 33. At the muffler pipe 29, the burring portion 31, the pipe member 33, and the connecting member 47, the annular protrusion 2 protruding outward along the outer periphery thereof.
Since 9b, 31b, 33b, and 47b are formed in a polymerized state, the sealability can be greatly improved with a simple structure as compared with the conventional case.

Further, in the pipe connecting method to the silencer of this embodiment, the muffler pipe 29,
Burring part 31, pipe member 33 and connecting member 47
Annular protrusions 29b, 31 protruding outward along the outer periphery of the
Since b, 33b and 47b are formed in a superposed state, the pipe connection structure to the silencer of the second embodiment can be easily and surely obtained.

FIG. 5 shows a third embodiment of the pipe connecting method to the silencer and an embodiment of the pipe connecting structure according to the present invention. In this embodiment, the pipe is connected to the silencer along the outer periphery thereof. An annular protrusion 31c is formed so as to protrude in one direction. The pipe member 33 is plastically deformed and fitted on the outer periphery of the annular protrusion 31c of the burring portion 31 to form the annular protrusion 33c.

The muffler pipe 29 of the silencer 23 described above
The pipe member 33 is connected to the pipe member 33 as described below. First, as shown in (a) of FIG. 6, the annular protrusion 3 that protrudes outward along the outer periphery of the burring portion 31 in advance.
1c is formed, and the outer periphery of the annular protrusion 31c is inserted into the enlarged diameter portion 33d of the pipe member 33.

Next, as shown in (b), the expanded diameter portion 33d.
A metal piece 49 on which an arcuate portion 49a having a shape corresponding to the annular protrusion 31c is formed is rolled along the outer periphery of the, and the expanded diameter portion 33d is plastically deformed by the annular protrusion 31c of the burring portion 31. The enlarged diameter portion 33d of the pipe member 33 is fitted to form the annular protrusion 33c.

In the pipe connecting structure to the muffler of the third embodiment, an annular projection 31c is formed so as to project outward along the outer circumference of the burring portion 31, and the outer circumference of the annular projection 31c of the burring portion 31 is formed. Since the pipe member 33 is plastically deformed and fitted, the sealability can be greatly improved with a simple structure as compared with the conventional case. Further, in the pipe connecting method to the muffler of this embodiment, the expanded diameter portion 33d of the pipe member 33 is plastically deformed so that the expanded diameter portion 33d of the pipe member 33 is fitted to the annular projection 31c of the burring portion 31. Because I chose
The pipe connection structure to the muffler of the third embodiment can be easily and surely obtained.

In the above-described first and second embodiments, an example in which bulge processing is performed by the bulge processing device 37 using the urethane member 39 has been described, but the present invention is limited to such embodiments. Not, for example,
Bulge processing by hydraulic pressure, bulge processing by a metal piece, etc. may be used. Further, in addition to the bulge processing, the deformation processing may be performed with a metal roller.

Further, in the above-described embodiment, the silencer 23
Although the example in which the present invention is applied to the connection of the exhaust pipe to the muffler pipe 29 has been described, the present invention is not limited to such an embodiment, and is also applied to, for example, the connection of the finisher pipe to the muffler pipe. be able to.

[0035]

As described above, in the pipe connecting structure to the muffler according to the first aspect of the present invention, the annular protrusion protruding outward is formed along the outer periphery of the burring part, and the annular protrusion of the burring part is formed. Since the pipe member is plastically deformed and fitted on the outer periphery, the sealing property can be greatly improved as compared with the conventional structure with a simple structure. In the pipe connecting method to the muffler according to the second aspect of the present invention, the muffler pipe, the burring portion, and the annular protrusion protruding outward along the outer circumference of the pipe member are formed in a superposed state by bulge processing. With such a structure, it is possible to easily and surely obtain a connection structure of pipes which can significantly improve the sealing property as compared with the conventional structure.

In the pipe connecting method to the muffler according to the third aspect of the present invention, the muffler pipe, the burring portion, the annular member protruding outward along the outer circumferences of the pipe member and the connecting member are formed in a superposed state by bulging. I did so,
It is possible to easily and surely obtain a connecting structure for pipes, which has a simple structure and can significantly improve the sealing property as compared with the conventional structure. In the method of connecting a pipe to a silencer according to a fourth aspect of the present invention, the expanded diameter portion of the pipe member is plastically deformed, and the expanded diameter portion of the pipe member is fitted to the annular protrusion of the burring portion. The pipe connection structure to the silencer can be obtained easily and surely.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of a method for connecting a pipe to a silencer of the present invention.

FIG. 2 is an explanatory diagram showing a method of connecting pipe members to the muffler pipe of FIG.

FIG. 3 is a cross-sectional view showing a second embodiment of the pipe connecting method to the silencer of the present invention.

FIG. 4 is an explanatory view showing a method of connecting pipe members to the muffler pipe of FIG.

FIG. 5 is a cross-sectional view showing a third embodiment of the pipe connecting method to the muffler of the present invention.

FIG. 6 is an explanatory view showing a method of connecting pipe members to the muffler pipe of FIG.

FIG. 7 is a perspective view showing a conventional pipe connection structure to a silencer.

[Explanation of symbols]

23 silencer 25 end plate 25a through hole 29 Muffler pipe 31 Burling part 33 Pipe member 29a, 31a, 33a Annular protrusion 29b, 31b, 33b, 47b Annular protrusion 31c, 33c Annular protrusion 47 Connecting member

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F01N 7/08 F01N 1/08 F16L 41/08

Claims (4)

(57) [Claims] 1. A pipe member (33) is connected to a protrusion of a muffler pipe (29) protruding outward from a through hole (25a) formed in an end plate (25) of a silencer (23). In the pipe connection structure to the silencer, the through hole (25) of the end plate (25) of the silencer (23) is provided.
A burring portion (3) protruding outward along the periphery of a).
1) and an annular protrusion (31c) protruding outward along the outer periphery of the burring part (31), and the annular protrusion (31) of the burring part (31) is formed.
A pipe connecting structure to a muffler, characterized in that a pipe member (33) is plastically deformed and fitted to the outer periphery of (c). 2. A pipe member (33) for connecting to a protruding portion of a muffler pipe (29) protruding outward from a through hole (25a) formed in an end plate (25) of a silencer (23). In the method for connecting a pipe to a silencer, the through hole (25) of the end plate (25) of the silencer (23) is used.
After fitting the pipe member (33) to the outer periphery of the burring part (31) formed to project outward along the peripheral edge of (a), the muffler pipe (29) and the burring part (3).
1) and the overlapped portion of the pipe member (33) are plastically deformed by bulging, and an annular protrusion protruding outward along the outer periphery of the muffler pipe (29), the burring portion (31) and the pipe member (33). (29a, 31a, 33a)
A method for connecting a pipe to a silencer, characterized in that the pipes are formed in a superposed state. 3. A pipe member (33) for connecting to a protruding portion of a muffler pipe (29) protruding outward from a through hole (25a) formed in an end plate (25) of a silencer (23). In the method of connecting a pipe to a muffler, the pipe member (3) is provided on the outer periphery of the muffler pipe (29).
3) is fitted and the end face of the pipe member (33) is formed so as to project outward along the peripheral edge of the through hole (25a) of the end plate (25) of the silencer (23) ( Three
After contacting the end face of 1), a coupling member (47) is fitted on the outer periphery of the butt portion of the burring portion (31) and the pipe member (33), and the burring portion (31) and the pipe member (33). At the butt portion of the muffler pipe (29), the burring portion (31), the pipe member (3
3) and the connecting member (47) are plastically deformed by bulging, and the muffler pipe (29) and the burring portion (3
1), an annular protrusion (29b, 31b,) protruding outward along the outer periphery of the pipe member (33) and the connecting member (47).
33b, 47b) is formed in a superposed state, a pipe connecting method to a silencer. 4. A pipe member (33) is connected to a protrusion of a muffler pipe (29) protruding outward from a through hole (25a) formed in an end plate (25) of a silencer (23). In the method for connecting a pipe to a silencer, the through hole (25) of the end plate (25) of the silencer (23) is used.
After forming an annular protrusion (31c) protruding outward along the outer periphery of the burring part (31) formed so as to protrude outward along the peripheral edge of a), the annular shape of the burring part (31) is formed. The outer circumference of the protrusion (31c) is inserted into the enlarged diameter portion (33d) of the pipe member (33), the enlarged diameter portion (33d) is plastically deformed, and the annular protrusion (31c) of the burring portion (31) is formed. The enlarged diameter portion (3) of the pipe member (33)
3d) is fitted, and a pipe connecting method to a silencer.