JP2005330839A - Exhaust pipe connection structure in muffler - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To insert an exhaust pipe into a predetermined position of a muffler main body without enhancing accuracy of positions for opening through-holes on an outer shell, enhance degrees of freedom of the positions for opening the through-holes by omitting burring processing, and simplify work processes. <P>SOLUTION: The both through-holes 11a, 11a are formed larger than outer diameter of an inlet tube 5. Reinforcing and gap closing members 7 having cylindrical parts 71 closely contacting outer peripheral faces of projecting parts of the inlet tube 5 and flange parts 72 projecting outwardly from edge parts of the through-holes 11a, 11a of the cylindrical parts 71 are fitted into positions of the inlet tube 5 corresponding to the both through-holes 11a, 11a. The flange parts 72 of the reinforcing and gap closing members 7 are welded and fixed to the circumference of the outer peripheral face of the outer shell 11 around the through-holes 11a, 11a. The cylindrical parts 71 of the reinforcing and gap closing members 7 are welded fixedly to the whole outer peripheral face of the inlet tube 5. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an exhaust pipe connection structure in a muffler.

  Conventionally, as an exhaust pipe connection structure in a muffler, for example, as shown in FIG. 9, a case (outer shell) 102 having both ends shielded by elliptical end plates 101, 101 and having a hollow inside, and the above case A plurality of chambers (silence chambers) 104 formed by partitioning a plurality of partition walls 103 so as to have different volumes in the internal cavities 102, and exhaust gas passing through the chambers 104 through the chambers 104. Exhaust gas provided through the case 102 so that the exhaust gas can flow into one chamber 104 formed inside the case 102 and a large number of communication means 105 that allow the gas to pass through in sequence. Gas inflow means (inlet exhaust pipe) 106 and exhaust gas that has passed through the multiple chambers 104 are transferred to the case 10. The outside through the case 102 to discharge the formed exhaust gas outflow means (outlet exhaust pipe) 107 and the vehicle muffler which is composed are known (e.g., see Patent Document 1.).

  In this conventional example, when the exhaust pipe (exhaust gas inflow means 106, exhaust gas outflow means 107) is inserted from the side of the outer shell (case 102), a through hole is opened and the through hole and the exhaust pipe In order to prevent gas leakage between the pierced hole and the outer shell in which the pierced hole is formed, the patch is fixed by spot welding, and an exhaust pipe is inserted into the pierced hole. The entire circumference of the joint of the outer shell, patch and exhaust pipe is welded.

JP-A-10-169428 (Specification (2) page, FIGS. 1 to 4)

However, since burring is performed from the inner side to the outer side after the outer shell is wound, it is difficult to burring the outer shell depending on the position and angle at which the through hole is opened. In the outer shell, there is a problem that it is more difficult. Also, the burring is provided for the purpose of preventing gas leakage between the through hole and the exhaust pipe, and it is almost between the exhaust pipe to be inserted. Since the inner diameter is formed so that there is no gap, it is necessary to improve the accuracy of the position where the through hole is opened, and there is a problem that correction cannot be made if the position is incorrect.

  The problem to be solved by the present invention is that the exhaust pipe can be inserted and fixed at a predetermined position of the outer shell without increasing the accuracy of the position of making the through hole in the outer shell, and the through hole is eliminated by omitting the burring process. It is an object to provide an exhaust pipe connection structure in a muffler that can increase the degree of freedom of the position where the valve is opened.

  In order to solve the above-mentioned problem, the exhaust pipe connection structure in the muffler according to claim 1 is a state in which a through-hole penetrating through the hollow portion of the muffler body is provided on the side wall of the outer shell constituting the muffler body, and the through-hole is penetrated In the exhaust pipe connection structure in the muffler, an exhaust pipe whose one end is closed is inserted and fixed, and a communication hole communicating with the inside of the hollow portion of the muffler body is formed on the side wall of the exhaust pipe. A cylindrical portion that is in close contact with the outer peripheral surface of the projecting portion of the exhaust pipe and outward from the side edge of the through hole of the cylindrical portion. A reinforcing and gap closing member each having a flange portion projecting on the flange portion, and the flange portion of the reinforcing and gap closing member is arranged around the through hole with respect to the outer surface of the outer shell. Ri together are welded, the cylindrical portion of the reinforcing and gap blockage member is a means which is characterized in that it is welded over its entire periphery to the outer peripheral surface of the exhaust pipe.

  The exhaust pipe connection structure in a muffler according to claim 2 is the exhaust pipe connection structure in a muffler according to claim 1, wherein the exhaust pipe is an inlet tube through which exhaust gas flows into the muffler body. It was.

  The exhaust pipe connection structure in the muffler according to claim 3 is the exhaust pipe connection structure in the muffler according to claim 1, wherein the exhaust pipe is an outlet tube for exhausting exhaust gas from the inside of the muffler body. It was.

In the exhaust pipe connection structure in the muffler according to claim 1, as described above, the through hole is formed larger than the outer diameter of the exhaust pipe without forming a burring in the through hole. Since a predetermined annular gap is formed between the exhaust pipe and the exhaust pipe, the exhaust pipe can be inserted into a predetermined position of the muffler body without increasing the accuracy of the position where the through hole is made in the outer shell. Will be able to.
Further, since it is not necessary to form a burring in the through hole, the degree of freedom of the position for opening the through hole can be increased, and the mold and work process can be simplified.

  In addition, the through-hole corresponding position in the exhaust pipe includes a cylindrical portion that is in close contact with the outer peripheral surface of the protruding portion of the exhaust pipe, and a flange portion that protrudes outward from the through-hole side edge of the cylindrical portion. Reinforcing and gap closing members are respectively mounted, and the flanges of the reinforcing and gap closing members are welded and fixed to the outer surface of the outer shell around the through holes, and the cylindrical parts of the reinforcing and gap closing members are exhausted. By welding and fixing to the outer peripheral surface of the pipe over the entire circumference, even if a predetermined annular gap is formed between the through hole and the exhaust pipe, it is possible to completely prevent the exhaust gas from leaking. At the same time, the flange portion of the reinforcing and gap closing member is welded and fixed to the outer shell, so that the outer shell having the through hole is reinforced.

  The exhaust pipe connection structure in a muffler according to claim 2, wherein the exhaust pipe is constituted by an inlet tube that allows exhaust gas to flow into the muffler body, and the exhaust pipe connection structure in the muffler according to claim 3 It is possible to connect to the muffler body in a straight tubular state without bending the inlet pipe or outlet pipe in the muffler, by configuring the outlet tube that exhausts exhaust gas from the exhaust pipe. Can be raised.

  Embodiments of the present invention will be described below with reference to the drawings.

The exhaust pipe connection structure in the muffler of the first embodiment corresponds to the invention described in claims 1 and 2.
First, the exhaust pipe connection structure in the muffler of the first embodiment will be described with reference to the drawings.

  1 is a plan view showing a muffler to which the exhaust pipe connection structure in the muffler of the first embodiment is applied, FIG. 2 is an enlarged sectional view taken along line II-II in FIG. 1, and FIG. 3 is taken along line III-III in FIG. 4 is an enlarged cross-sectional view taken along line IV-IV in FIG. 1, FIG. 5 is a view taken in the direction of arrow A in FIG. 2, and FIG. 6 is a view taken in the direction of arrow B in FIG. A muffler main body 1, inner plates 2, 3, 4, an inlet tube (exhaust pipe) 5, an outlet tube 6, a reinforcing and gap closing member 7, and an exhaust control valve 8 are provided as main components.

More specifically, the muffler body 1 is composed of a cylindrical outer shell 11 and outer plates 12 and 13 that close both end openings of the outer shell 11.
The muffler body 1 has four muffler chambers (resonance chambers) 1a and muffler chambers (expansion chambers) with three inner plates 2, 3, and 4 in the muffler body 1 at predetermined intervals in the longitudinal direction. ) 1b, silencer chamber (expansion chamber) 1c, and silencer chamber (expansion chamber) 1d.

  The outlet tube 6 passes through the outer plate 12 and all the inner plates 2, 3, 4 and is opened to the sound deadening chamber 1 d on the inlet 6 a side, and the outlet side is disposed outside the muffler body 1.

  As shown in FIG. 4, the inlet tube 5 is provided so as to penetrate the side wall of the outer shell 11. That is, on the side wall of the outer shell 11, two through holes 11a and 11a penetrating through the muffler chamber 1b in the muffler body 1 are opened, and the inlet tube 5 is inserted through the through holes 11a and 11a. It is inserted.

  The through holes 11a and 11a are formed larger than the outer diameter of the inlet tube 5 inserted into the through holes 11a and 11a, thereby enabling fine adjustment of the positional relationship between the muffler body 1 and the inlet tube 5.

  The opening on the opposite side of the inlet tube 5 from the inlet 5a is closed by a lid member 51, and a plurality of small holes 5b communicating with the inside of the sound deadening chamber 1b are formed in the peripheral wall of the inlet tube 5. Has been.

  The reinforcing and gap closing member 7 closes the gap between the through holes 11 a and 11 a opened in the side wall of the outer shell 11 and the inlet tube 5 and connects and fixes the outer shell 11 and the inlet tube 5. A cylindrical portion 71 that is in close contact with the outer peripheral surface of the inlet tube 5 on the outside of the outer shell 11 and protrudes outwardly from the side holes of the through holes 11a and 11a of the cylindrical portion 71. And a flange portion 72 having an arcuate cross section along the outer surface.

  The flange portion 72 of the reinforcing and gap closing member 7 is fixed to the outer surface of the outer shell 11 by welding around the entire circumference of the through holes 11a and 11a, and the cylindrical portion 71 of both the reinforcing and gap closing member 7 is fixed. The entire circumference of the inlet tube 5 is fixed by welding. In addition, all welding, such as plasma welding, laser welding, seam welding, or TIG welding, can be applied for welding.

  2 and 3, the exhaust control valve 8 is provided in a through hole 31 that penetrates the inner plate 3, and closes the through hole 31 with a predetermined urging force from the sound deadening chamber 1c side. Is provided. Further, the inner plate 3 is formed with a plurality of small holes 32 communicating with both the muffler chambers 1b-1c.

The inner plate 4 is formed with a plurality of small holes 41 communicating between the sound deadening chambers 1c-1d. The total opening area of the small holes 42 is formed to be substantially the same as the total opening area of the through holes 31 and the small holes 32 in the inner plate 3.
In addition, the inner plate 2 is formed with a plurality of small holes 21 communicating between the two silencing chambers 1a and 1b, so that the silencing chamber 1a forms a resonance chamber.

Next, the operation of the first embodiment will be described.
Since the exhaust pipe connection structure in the muffler of the first embodiment is configured as described above, the urging force of the exhaust control valve 8 is set to such an extent that the engine speed does not open in a predetermined low speed range. By doing so, the exhaust pressure flowing through the muffler body 1 is small when the engine is running at a low speed, so that the exhaust control valve 8 is kept closed as shown in FIGS.

  Thus, when the exhaust control valve 8 is closed, the exhaust from the engine flows into the silencer chamber 1b from the small hole 5b of the inlet tube 5, and the exhaust gas flowing into the silencer chamber 1b flows into the inner plate 3 Since the through hole 31 is closed by the exhaust control valve 8, the through hole 31 flows into the silencer chamber 1 c through the plurality of small holes 32 formed in the inner plate 3. Then, after flowing into the sound deadening chamber 1d through the plurality of small holes 41 formed in the inner plate 4 from inside the sound deadening chamber 1c, the air is exhausted outside the vehicle via the outlet tube 6.

  As described above, the exhaust gas flowing into the silencing chamber 1b is expanded when flowing into the silencing chamber 1c by closing the large-diameter through hole 31 formed in the inner plate 3 and passing only through the small hole 32. Therefore, the noise reduction requirement required at the time of low-speed rotation of the engine can be satisfied.

  Next, when the engine speed exceeds a predetermined low speed rotation range and the exhaust pressure exceeds the valve closing force based on the urging force of the exhaust control valve 8, the exhaust control valve 8 is pushed open toward the silencing chamber 1c side. The valve opens.

As described above, when the exhaust control valve 8 is opened, the exhaust from the engine flows into the silencer chamber 1b from the small hole 5b of the inlet tube 5, and the exhaust gas flowing into the silencer chamber 1b passes through the inner plate. 3 flows through the three through holes 31 and the plurality of small holes 32 into the sound deadening chamber 1c. Then, after flowing into the sound deadening chamber 1d through the plurality of small holes 41 formed in the inner plate 4 from inside the sound deadening chamber 1c, the air is exhausted outside the vehicle via the outlet tube 6.
As described above, since the through-hole 31 is opened in addition to the plurality of small holes 32, the exhaust flow resistance required at the time of high-speed rotation of the engine is reduced, so that a decrease in engine output can be suppressed. .

  As described above in detail, according to the exhaust pipe connection structure in the muffler of the first embodiment, the burring is not formed in the through holes 11a and 11a provided in the side wall of the outer shell 11 as described above. Since the through holes 11a and 11a are formed larger than the outer diameter of the exhaust pipe, a predetermined annular gap is formed between the through holes 11a and 11a and the inlet tube 5 so that the position can be corrected. The inlet tube 5 can be inserted and arranged at a predetermined position of the muffler body 1 without increasing the accuracy of the position where the through holes 11a and 11a are opened in the outer shell 11, so that they intersect with the outlet tube 6 without colliding. As a result, the workability can be improved.

In addition, since it is not necessary to form burring in the through holes 11a and 11a, it is possible to increase the degree of freedom of positions where the through holes 11a and 11a are opened, and to simplify the work process. In addition, a simple work tool can be used.
Further, since the through-holes 11a and 11a are opened after the outer shell 11 is wound, it is more difficult to cause burring when the outer shell 11 has a plurality of windings. Therefore, it is only necessary to open the through-holes 11a and 11a. The structure of Example 1 is more effective.
Further, when the muffler main body 1 is constituted by winding a plurality of parts, it is not necessary to provide a burring in each overlapped portion, so that the mold accuracy is not so much required, thereby improving workability.

In addition, at the positions corresponding to both the through holes 11 a and 11 a in the inlet tube 5, there are a cylindrical portion 71 that is in close contact with the outer peripheral surface of the protruding portion of the inlet tube 5, and an edge portion on the side of the through holes 11 a and 11 a Reinforcing and gap closing members 7 each having an outwardly projecting flange portion 72 are mounted, and the flange portions 72 of both the reinforcing and gap closing members 7 are around the through holes 11 a and 11 a with respect to the outer surface of the outer shell 11. While being fixed by welding over the entire circumference, the cylindrical portion 71 of both reinforcing and gap closing members 7 is welded and fixed to the outer peripheral surface of the inlet tube 5 over the entire circumference, thereby allowing the through holes 11a and 11a and the inlet tube to be fixed. Even if a predetermined annular gap is formed between the exhaust gas and the exhaust gas, it is possible to completely prevent the exhaust gas from leaking. The portion is welded and fixed to the outer shell 11, so that the outer shell 11 with the through holes 11a and 11a opened is reinforced, thereby improving durability even if the plate thickness of the outer shell 11 is reduced. The effect that it will be able to do is acquired.
Further, due to restrictions on the layout of the vehicle, when the muffler main body 1 is placed in the horizontal direction in the longitudinal direction of the vehicle, it becomes possible to easily provide the tube without bending.

  Next, another embodiment will be described. In the description of the other embodiments, the same components as those of the first embodiment are not shown, or the same reference numerals are given and the description thereof is omitted, and only the differences are described.

  The second embodiment shows a modification of the apparatus in the first embodiment. As shown in the enlarged cross-sectional view of the main part of FIG. 7, the opening on the opposite side of the inlet 5a of the inlet tube 5 is closed. The point that the lid member 51 is integrally formed with the reinforcing and gap closing member 7 is different from the first embodiment.

  Therefore, in the second embodiment, the same effect as in the first embodiment can be obtained, and the trouble of welding the lid member 51 and the cylindrical portion 71 to the outer peripheral surface of the inlet tube 5 can be saved, and the number of parts can be reduced. The additional effect of being able to reduce is obtained.

  The third embodiment shows a modification of the apparatus in the first embodiment. As shown in the enlarged cross-sectional view of the main part in FIG. 8, the third embodiment is a side opposite to the inlet 5 a of the inlet tube 5 with respect to the outer shell 11. The fixing structure is different from the first and second embodiments in that the fixing member 9 is fixed to the inner surface side of the outer shell 11 without penetrating the outer shell 11 (without opening one through hole 11a). Is.

  That is, the fixing member 9 protrudes outward from the cylindrical portion 91 in close contact with the outer peripheral surface of the inlet tube 5 inside the outer shell 11 and the side edge portion of the cylindrical portion 91, and extends along the inner surface of the outer shell 11. And a flange portion 92 having an arcuate cross section.

  The flange portion 92 of the fixing member 9 is fixed to the inner peripheral surface of the outer shell 11 by welding, and the cylindrical portion 91 is fixed to the outer peripheral surface of the inlet tube 5 by welding as necessary. In addition, all welding, such as plasma welding, laser welding, seam welding, or TIG welding, can be applied for welding. Further, in this case, since it is not necessary to seal with the outside, spot welding may be used.

  Therefore, in this third embodiment, the same effect as in the first embodiment can be obtained, and the number of through holes 11a formed in the outer shell 11 can be reduced, so that work efficiency can be increased. The effect is obtained.

Although the present embodiment has been described above, the present invention is not limited to the above-described embodiment, and design changes and the like within a scope not departing from the gist of the present invention are included in the present invention.
For example, in the embodiment, the exhaust pipe connection structure in the muffler of the present application is applied to the inlet tube 5, but can also be applied to the outlet tube 6.
Moreover, the layout in the muffler main body 1 is arbitrary.

It is a top view which shows the muffler to which the exhaust pipe connection structure in the muffler of Example 1 was applied. It is an expanded sectional view in the II-II line of FIG. It is sectional drawing in the III-III line of FIG. It is an expanded sectional view in the IV-IV line of FIG. FIG. 3 is a view as seen from an arrow A in FIG. 2. FIG. 3 is a view taken in the direction of arrow B in FIG. 2. It is a principal part expanded sectional view which shows the muffler to which the exhaust pipe connection structure in the muffler of Example 2 was applied. It is a principal part expanded sectional view which shows the muffler to which the exhaust pipe connection structure in the muffler of Example 3 was applied. It is sectional drawing which shows the exhaust pipe connection structure in the muffler of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Muffler body 1a Silent room 1b Silent room 1c Silent room 1d Silent room 11 Outer shell 11a Through hole 12 Outer plate 13 Outer plate 2 Inner plate 21 Small hole 3 Inner plate 31 Through hole 32 Small hole 4 Inner plate 41 Small hole 5 Inlet Tube (exhaust pipe)
5a Inlet 5b Small hole 51 Lid 6 Outlet tube 6a Inlet 7 Reinforcement and gap closing member 71 Cylindrical part 72 Flange part 8 Exhaust control valve 9 Fixing member 91 Cylindrical part 92 Flange part

Claims (3)

A through hole penetrating the inside of the hollow portion of the muffler body is provided on the side wall of the outer shell constituting the muffler body, and an exhaust pipe having one end closed in a state of passing through the through hole is inserted and fixed, and the side wall of the exhaust pipe In the exhaust pipe connection structure in the muffler in which a communication hole communicating with the inside of the hollow portion of the muffler body is formed,
The through hole is formed larger than the outer diameter of the exhaust pipe;
The exhaust pipe is provided with a cylindrical portion in close contact with the outer peripheral surface of the projecting portion of the exhaust pipe and a flange portion projecting outward from the through-hole side edge of the cylindrical portion at the position corresponding to the through hole in the exhaust pipe. Reinforcement and gap closing members are installed,
The flange portion of the reinforcing and gap closing member is welded and fixed to the outer surface of the outer shell around the through hole, and the cylindrical portion of the reinforcing and gap closing member is fixed to the outer surface of the exhaust pipe. An exhaust pipe connection structure in a muffler characterized by being fixed by welding over the entire circumference.   2. The exhaust pipe connection structure for a muffler according to claim 1, wherein the exhaust pipe is an inlet tube for allowing exhaust gas to flow into the muffler body.   2. The exhaust pipe connection structure for a muffler according to claim 1, wherein the exhaust pipe is an outlet tube for exhausting exhaust gas from the muffler body.

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