JP2587690Y2 - Silencer - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a muffler mounted on a vehicle exhaust system.

[0002]

2. Description of the Related Art In order to reduce exhaust noise during vehicle running,
Conventionally, a muffler as disclosed in Japanese Utility Model Laid-Open Publication No. 59-133714 is installed in a vehicle exhaust system, and an expansion attenuation function of exhaust energy in an expansion chamber of the muffler and a resonance chamber are used. Exhaust noise is silenced by the resonance damping effect of.

However, with the increase in the number of high-performance engines, high-frequency burr noise generated from the exhaust discharge port at the time of cold tends to occur frequently as a user complaint. Such burr noise generally occurs when the engine is rapidly accelerated or decelerated or when the engine is not completely warmed up. In fact, the silencer having the above-described structure cannot muffle the burr sound. Was.

Therefore, recently, in order to prevent such burr noise,
As shown in Japanese Utility Model Laid-Open Publication No. 64-36615 or FIG. 4, a silencer 5 in which an exhaust chamber 3 is mounted on an outlet pipe 1 is widely used.

[0005] The exhaust chamber 3 comprises an outer cylinder 7 surrounding the outlet pipe 1 in the muffler 5 and glass wool 9 filled in the outer cylinder 7, and the outlet pipe surrounded by the outer cylinder 7. A large number of small holes 11
Are drilled.

[0006] Reduced diameter portions 7a, 7 are provided at both ends of the outer cylinder 7.
b is formed, the reduced diameter portion 7a on the upstream side is welded to the outer periphery of the outlet pipe 1 and the outer reduced diameter portion 7a is inserted into the outer cylinder insertion hole 18 of the baffle plate 17 that partitions the first expansion chamber 13 and the resonance chamber 15. The cylinder 7 is press-fitted, and the exhaust chamber 3 is held by a baffle plate 17. And
Usually, the outer cylinder insertion hole 18 is formed by burring.

Thus, according to the silencer 5, together with the exhaust energy of the high-frequency component emitted from the engine,
The burr is absorbed by the glass wool 9 in the exhaust chamber 3.

In the drawings, reference numerals 19 and 21 denote end plates for closing both ends of the shell 23, 25 an inlet pipe, and 27 and 29 baffle plates.

[0009]

By the way, as the exhaust gas discharged from the engine flows into the silencer 5 through the inlet pipe 25, the temperature of the silencer 5 gradually increases, and the outlet pipe 1 and the outer cylinder 7 are heated. Expands thermally, but there is a difference in thermal expansion between the outer cylinder 7 and the outlet pipe 1.

Therefore, in order to prevent the occurrence of cracks due to the difference in thermal expansion between the two, conventionally, the reduced diameter portion 7b on the downstream side of the outer cylinder 7 is made to be a free end with respect to the outer periphery of the outlet pipe 1, and The outer circumference is slidable. Also, as described above, the outer cylinder 7 and the baffle plate 17
Is not fixed, and the outer cylinder 7 is press-fitted and held in the outer cylinder insertion hole 18.

Therefore, as the muffler 5 becomes hotter,
In the outer cylinder 7, the reduced diameter portion 7b slides on the outer periphery of the outlet pipe 1 and slides through the press-fitted outer cylinder insertion hole 18 so that the outlet pipe 1 is inserted in the direction of press-fitting (FIG. 5).
(In the direction of arrow A).

Then, the silencer 5 is activated by stopping the engine.
When the outer cylinder 7 cools, the outer cylinder 7 contracts in the opposite direction (the direction of arrow B in the figure). At this time, the baffle plate 17 at the peripheral edge of the outer cylinder insertion hole 18
5 is pulled in the same direction with the movement of the outer cylinder 7 and deformed as shown by a two-dot chain line in FIG. When the deformation exceeds a certain limit, the shape returns to the original shape as shown by the solid line. When the baffle plate 17 returns to the original shape beyond the certain limit, the baffle plate 17 suddenly Since it is restored, there is a possibility that intense friction occurs between the outer cylinder 7 and the baffle plate 17 and abnormal noise is generated.

Since the cause of such abnormal noise is caused by the internal structure of the muffler, the user cannot understand the cause, and the user is unnecessarily nervous.

The present invention has been devised in view of the above circumstances, and a vehicle exhaust system which prevents generation of abnormal noise between the outer cylinder and the baffle plate when the outer cylinder of the exhaust chamber contracts after thermal expansion. The object of the present invention is to provide a silencer.

[0015]

In order to achieve the above object, according to the present invention, an exhaust chamber is mounted on an outlet pipe in a shell, and an outer cylinder of the exhaust chamber is replaced with an outer cylinder of a baffle plate. In the vehicle exhaust system silencer inserted into the insertion hole , close the outer cylinder insertion hole with the outer cylinder.
And the edge side of the peripheral edge of the outer cylinder insertion hole is expanded.
When opened, the edge is separated from the outer cylinder in a non-contact state . And the invention according to claim 2 is the invention according to claim 2
In the muffler according to the item 1, the car around the opening edge of the outer cylinder insertion hole
The outer cylinder insertion hole, and
It is separated from the outer cylinder in a non-contact state.

The invention according to claim 3 is characterized in that the shell inside
Attach an exhaust chamber to the outlet pipe, and
Insert the outer cylinder of the chamber into the outer cylinder insertion hole of the baffle plate.
In the silencer of the vehicle exhaust system that is inserted,
A holding member is interposed between the outer cylinder and the outer cylinder insertion hole and the outer cylinder.
The space is closed by the holding member, and
Then, the edge of the opening peripheral edge of the outer cylinder insertion hole is not connected to the outer cylinder.
It is characterized in that it is separated in a contact state. And claims
According to a fourth aspect of the present invention, in the muffler according to the third aspect, the holding portion is provided.
The material is a ring-shaped elastic metal member,
In the invention according to claim 5, the holding member is fixed to the outer periphery of the outer cylinder.
The exhaust chamber holding member having a substantially J-shaped cross section,
The outer peripheral edge of the outer cylinder insertion hole is
It is characterized by being engaged.

[0017]

As the exhaust gas discharged from the engine flows into the silencer, the temperature of the silencer gradually increases, and the outer cylinder of the exhaust chamber thermally expands.

The outer cylinder extends in the direction of press-fitting the outlet pipe while sliding in the outer cylinder insertion hole, and when the silencer cools down due to the stop of the engine, the outer cylinder contracts in the opposite direction to move outward. baffle plate of the cylindrical insertion hole peripheral portion to deform in the same direction with the movement of the outer tube, but claim 1 及
The invention according to claim 2 is characterized in that:
Since the edge side is expanded and the edge is separated from the outer cylinder in a non-contact state, the edge portion of the baffle plate does not bite into the outer periphery of the outer cylinder when the outer cylinder contracts.

Further, the mute according to claim 3 to claim 5 is provided.
In the container, a holding member is interposed between the outer cylinder insertion hole and the outer cylinder,
Edge of the peripheral edge of the opening of the outer cylinder insertion hole via the holding member
Is a structure that is separated from the outer cylinder in a non-contact state
In addition, the outer cylinder is inserted through the holding member by thermal expansion.
It expands and contracts while easily sliding the attachment hole, and the periphery of the outer cylinder insertion hole.
The baffle plate of the part hardly deforms. Claim 4
In the silencer according to the above, it was slightly deformed with the movement of the outer cylinder
Later, even if it returns to the original shape, the outer cylinder and the baffle plate
The elastic metal member also prevents the generation of sliding noise between
You.

[0020]

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. Since the configuration other than the devised portion is the same as that of the conventional example shown in FIG. 4 and subsequent figures, the description thereof is omitted here, and only the devised portion will be described. The same components as those in the conventional example are denoted by the same reference numerals.

FIG . 1 shows a muffler according to claims 1 and 2.
In the figure, reference numeral 31 denotes a first expansion chamber 13 and a resonance chamber 15 similar to the conventional baffle plate 17 shown in FIG.
In the baffle plate partitioning the door, the baffle plate 31 to be closed to the outer tube insertion hole 33 provided, the outer cylinder 7 of the A Utore'<br/> exhaust chamber 3 mounted on the heat pipe 1 is pressed held I have.

The outer cylinder insertion hole 33 in this embodiment is
Is formed by curling instead of the conventional burring process, and has a structure in which a curl portion 35 is provided at the opening peripheral portion. By providing the curl portion 35 at the opening peripheral portion in this manner, the opening peripheral portion is formed. The edge 37 of the portion is separated from the outer cylinder 7 and does not contact the outer periphery of the outer cylinder 7.

In this embodiment, since the exhaust gas discharged from the engine flows, the temperature of the muffler gradually increases as the exhaust gas discharged from the engine flows into the outlet pipe 1.
Then, the outer cylinder 7 thermally expands.

As in the prior art, the outer pipe 7 slides through the inserted outer pipe insertion hole 33 while the outlet pipe 1 is inserted.
In the press-fitting direction (the direction of arrow A in FIG. 1). When the silencer cools down due to the stop of the engine, the outer cylinder 7 contracts in the opposite direction (the direction of arrow B in the figure), but in the present embodiment, the outer cylinder 7 curls around the opening periphery of the outer cylinder insertion hole 33. Part 35
And the edge 37 is in a non-contact state from the outer periphery of the outer cylinder 7.
, The edge 37 of the baffle plate 31 does not bite into the outer periphery of the outer cylinder 7 when the outer cylinder 7 contracts, and as a result, the curl portion 35 Since the slide is performed, the baffle plate 31 is not deformed as indicated by a two-dot chain line in the related art.

Therefore, according to the present embodiment, it is possible to reliably prevent generation of abnormal noise between the outer cylinder 7 and the baffle plate 31 due to contraction of the outer cylinder 7 of the exhaust chamber 3 after thermal expansion. Having. According to this embodiment, the outer cylinder
Since the insertion hole 33 is closed by the outer cylinder 7, the first expansion chamber
The function of 13 and the resonance chamber 15 is not impaired.

FIG. 2 shows a muffler according to claims 3 and 4.
In the figure, reference numeral 39 denotes a baffle plate for partitioning the first expansion chamber 13 and the resonance chamber 15; 41, an outer cylinder insertion hole 43 provided in the baffle plate 39; The elastic metal member 41 is a SUS formed in a cylindrical shape.
It is formed by winding wool into a donut shape and spot-welded to at least two locations on the outer periphery of the outer cylinder 7 and attached to the exhaust chamber 3.

The outer cylinder insertion hole 43 is burred to a size capable of holding the elastic metal member 41 mounted on the outer periphery of the exhaust chamber 3.
Insert the outlet pipe 1 into the exhaust chamber 3
By press-fitting the outer cylinder 7, the outer cylinder insertion hole 43 and the outer cylinder 7
Is closed by the elastic metal member 41, and the exhaust chamber is closed.
The bar 3 is made of the baffle plate 3 by the elastic metal member 41.
9 and through the elastic metal member 41
The edge 45 of the opening peripheral portion of the outer cylinder insertion hole 43 is
7 has a structure separated from the outer periphery in a non-contact state .

In this embodiment, the outer cylinder 7 extends in the direction of arrow A due to the thermal expansion accompanying the inflow of the exhaust gas. The elastic metal member 4 has less resistance to expansion and contraction of the outer cylinder 7 due to thermal expansion than the curled portion 35 in the first embodiment.
1 is interposed, the outer cylinder 7 is connected to the elastic metal member 4.
1, the outer cylinder insertion hole 43 is extended while easily sliding.

When the silencer cools down due to the stop of the engine, the outer cylinder 7 moves in the opposite direction (the direction of arrow B in the figure).
However, the outer cylinder 7 expands and contracts while easily sliding in the outer cylinder insertion hole 43 via the elastic metal member 41, and the outer cylinder insertion hole 43.
The baffle plate 39 at the peripheral edge of is hardly deformed.
Further, even if the outer cylinder 7 is slightly deformed in accordance with the movement of the outer cylinder 7 and returns to the original shape, the elastic metal member 41 also prevents the generation of sliding noise between the outer cylinder 7 and the baffle plate 39. .

Therefore, according to the present embodiment, it is of course possible to surely prevent generation of abnormal noise between the outer cylinder 7 and the baffle plate 39 due to the contraction of the outer cylinder 7 of the exhaust chamber 3 after thermal expansion. According to the present embodiment, since the elastic metal member 41 having less resistance to expansion and contraction of the outer cylinder 7 due to thermal expansion than the first embodiment is interposed, the outer cylinder 7 and the baffle plate 39 itself are provided. This also has the advantage that the occurrence of sliding noise with the above can be prevented and the dimensional accuracy can be made rough. or,
Also in this embodiment, the space between the outer cylinder insertion hole 43 and the outer cylinder 7 is
The first expansion chamber 1 is closed by the elastic metal member 41.
3 and the function of the resonance chamber 15 are not impaired.

FIG. 3 shows a muffler according to claims 3 and 5.
In the drawing, reference numeral 47 denotes an exhaust chamber holding member welded to the outer periphery of the outer cylinder 7 of the exhaust chamber 3 and having a substantially J-shaped cross section. The folded portion 47a and the base 47b of the exhaust chamber holding member 47 are shown in FIG. Is set slightly wider than the thickness m of the baffle plate 39. The abutment periphery of the opening peripheral edge portion of the outer tube insertion hole 43 on the inner periphery of the folding Kaehen 47a of the exhaust chamber holding member 47, and engage, the outer tube insertion hole of the exhaust chamber 3 is a baffle plate 39 43 Between the outer tube insertion hole 43 and the outer tube 7.
Are closed by an exhaust chamber holding member 47 . Further, the tip 47c of the folded piece 47a has a shape slightly expanded outward , and by thus expanding the tip 47c outward, the outer cylinder insertion hole 4 into the gap 49 is formed.
The periphery of the opening 3 is easy to insert.

Thus, according to the present embodiment, the intended purpose can be achieved similarly to the embodiment shown in FIG. In the embodiment shown in FIG. 2 , the elastic metal member 41 is mounted around the outer circumference of the outer cylinder 7 of the exhaust chamber 3, but may be spot-welded to the outer cylinder insertion hole 43 side. It is also possible to achieve the intended purpose.

[0034]

As described above, according to the invention described in the claims, when the outer cylinder of the exhaust chamber contracts after thermal expansion, generation of abnormal noise between the outer cylinder and the baffle plate is ensured. According to the invention of claim 4 , the elastic metal member has an effect of preventing the sliding noise between the outer cylinder and the baffle plate itself.

[Brief description of the drawings]

1 is an enlarged sectional view of a silencer according to an embodiment of claim 1 and claim 2.

FIG. 2 is an enlarged sectional view of a main part of a muffler according to an embodiment of the present invention.

FIG. 3 is an enlarged sectional view of a main part of a muffler according to an embodiment of the present invention.

FIG. 4 is a cross-sectional view of a conventional silencer.

FIG. 5 is an enlarged sectional view of a main part of the muffler shown in FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 outlet pipe 3 exhaust chamber 7 outer cylinder 9 glass wool 11 small hole 13 first expansion chamber 15 resonance chamber 31, 39 baffle plate 33, 43 outer cylinder insertion hole 35 curl portion 37, 45 edge 41 elastic metal member 47 exhaust chamber holding Element

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F01N 1/02-1/08

Claims (5)

(57) [Scope of request for utility model registration] An exhaust chamber (3) is mounted on an outlet pipe (1) in a shell, and an outer cylinder (7) of the exhaust chamber (3) is inserted into an outer cylinder insertion hole (33 ) of a baffle plate (31). In the vehicle exhaust system silencer inserted in ()), the outer cylinder insertion hole (33) is closed with the outer cylinder (7).
The edge (3) of the peripheral edge of the opening of the outer cylinder insertion hole (33)
7) Expand the side and move the edge (37) away from the outer cylinder (7).
A silencer characterized by being separated into a contact state . 2. A curl portion (35) is provided on the periphery of the opening of the outer cylinder insertion hole (33), and the edge (37) of the opening periphery of the outer cylinder insertion hole (33) is connected to the outer cylinder (7). 2. The silencer according to claim 1, wherein the silencer is separated from the contactless state . 3. An outlet pipe (1) in a shell.
Attach the exhaust chamber (3), and
Put the outer cylinder (7) of (3) outside the baffle plate (39).
In the silencer of the vehicle exhaust system inserted in the cylinder insertion hole (43)
Te, holding member between the outer tube insertion hole (43) the outer tube (7)
Between the outer tube insertion hole (43) and the outer tube (7).
While closing with the holding member, via the holding member,
Remove the edge (45) of the peripheral edge of the opening of the outer cylinder insertion hole (43).
Characterized in that it is separated from the cylinder (7) in a non-contact state.
Silencer. 4. The holding member is a ring-shaped elastic metal member.
The sound deadening according to claim 3, characterized in that (41).
vessel. 5. A holding member fixed to an outer periphery of an outer cylinder.
A substantially J-shaped exhaust chamber holding member (47)
The outer chamber insertion hole (4
The peripheral edge of the opening of (3) is engaged.
Item 7. The silencer according to Item 3.