JPH032664Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is used for flexible exhaust pipes.

[Conventional technology]

There is something called a flexible exhaust pipe. A flexible exhaust pipe is an exhaust pipe made from a flexible bellows pipe.
Prior art documents disclosing flexible exhaust pipes include, for example, Utility Model Application No. 40885 (1983), Utility Model Application No. 40885 (1983), and Utility Model Application No. 40885 (1983).
107816, Utility Model 57-46179, Utility Model 55-110723,
Examples include Utility Model 57-46180 and Utility Model 57-33218.

The flexible exhaust pipe is provided in the middle of the exhaust pipe 1, as shown in FIG. 21st
In the figure, 10 is a flexible exhaust pipe.

In FIG. 21, 2 is an engine, 3 is an exhaust manifold, 4 is a catalytic converter, and 5 is a muffler. Further, 6 represents a suspension member that suspends the entire exhaust system on the body of the automobile.

The reason why the flexible exhaust pipe 10 is provided in the middle of the exhaust pipe 1 is that the vibrations of the engine 2 are
This is to prevent the vibration from being transmitted to the entire body, thereby reducing idle vibration and muffled noise.

FIG. 22 is an enlarged longitudinal sectional view of a conventional flexible exhaust pipe 10.

In FIG. 22, 11 is a bellows tube, and 12 is an outer cylinder. The flexible exhaust pipe 10 is a bellows pipe 11
is covered with an outer cylinder 12.

In the flexible exhaust pipe 10, an inner cylinder 13 is also inserted into the bellows pipe 11. Arrow G represents the flow of exhaust gas.

In the flexible exhaust pipe 10, the bellows pipe 11
The inner cylinder 13 is inserted into the inner cylinder 1.
3, noise will be generated from the flexible exhaust pipe 10. That is, without the inner cylinder 13,
Since the exhaust gas (arrow G) is pulsating, the bellows tube 11 resonates using this pulsating pressure as an excitation source. This resonance is emitted into the air as noise. This is the reason why noise is generated from the flexible exhaust pipe 10 without the inner cylinder 13.

If the inner cylinder 13 is inserted into the bellows tube 11, the pulsating pressure of exhaust gas will not directly hit the bellows tube 11. Therefore, in order to reduce noise, the bellows pipe 1
An inner cylinder 13 is inserted into the inner cylinder 1. (for example,
Utility model 57-46180, 1987-110723, 1987 Utility development
−46179).

Further, regarding the flexible exhaust pipe 10, as described above, the bellows pipe 11 is covered with the outer cylinder 2, and the reason for this will be explained.

That is, the outer cylinder 12 is for protecting the bellows tube 11 from flying stones, rainwater, muddy water, dust, and the like. Particularly in cold regions, salt is sprinkled on roads to prevent them from freezing, so if the outer cylinder 12 is not present, salt water will leak into the bellows pipe 1.
However, the outer cylinder 12 is essential in order to prevent this salt water from adhering. This is because the temperature of the bellows pipe 11 is approximately 700 to 800°C due to the passage of exhaust gas, but if salt water adheres to the bellows pipe 11 at such a high temperature, it will cause damage even though the bellows pipe 11 is made of stainless steel. Regardless, corrosion progresses very quickly.

Note that the opening 23 of the outer cylinder 12 is opened rearward with respect to the direction of travel of the automobile (direction of arrow Q), and this is to prevent rainwater, muddy water, salt water, etc. from entering.

[Problem that the invention attempts to solve]

The conventional flexible exhaust pipe 10 shown in FIG. 22 has the following two problems.

Firstly, the bellows pipe 11 is connected to the arrow A while driving the car.
The problem is that the tip 21 of the outer cylinder 12 collides with the exhaust gas outlet pipe 22 and generates a sound when it vibrates in the -B direction.

The second problem is that even if the opening 23 is opened rearward with respect to the direction of travel of the vehicle (direction of arrow Q), rainwater, muddy water, salt water, etc. may enter through the beam opening 23. .

For the second problem above,
It has been proposed that the opening 23 has a labyrinth structure to make it difficult for rainwater, muddy water, salt water, etc. to enter.

Figure 23 is a reprint of a drawing from Utility Model Application Publication No. 60-40885. In FIG. 23, the part labeled 24 is the labyrinth structure part.

If it is the type shown in Figure 23, it will certainly be difficult for rainwater, muddy water, salt water, etc. to enter.

However, as can be seen from Figure 23, the second
Even in the case shown in FIG. 3, it cannot be said that the first problem, that is, the problem of noise, has been solved. This is because when the bellows tube 11 vibrates in the direction of the arrow AB, the outer tubes 12a and 12b collide in the labyrinth structure portion 24.

The present invention solves these problems of the conventional technology.

The technical problem of the present invention is to not only make it difficult for rainwater, muddy water, salt water, etc. to adhere to the bellows pipe in a flexible exhaust pipe, but also to reduce noise caused by collisions between outer cylinders.

[Means for solving problems]

In order to achieve this technical problem, the following measures are taken in the present invention.

That is, the flexible exhaust pipe according to the present invention includes a flexible bellows pipe, an outer cylinder covering the outside of the bellows pipe, an inner cylinder disposed inside the bellows pipe, and an inner cylinder. and an exhaust gas outlet pipe arranged coaxially with respect to the inner cylinder while maintaining a predetermined distance therebetween. One end of the bellows tube is welded to the inner cylinder and serves as an exhaust gas inlet. The other end of the bellows pipe is welded to an exhaust gas outlet pipe to serve as an exhaust gas outlet. One end of the outer cylinder is welded to the bellows tube at the exhaust gas inlet. A stay is attached to the exhaust gas outlet pipe, and the tip of the outer cylinder and the tip of the stay are arranged close to each other and have a labyrinth structure. Further, a cushioning material is attached to at least one of the distal end portion of the outer cylinder and the distal end portion of the stay to soften the impact.

The above are the measures taken in the present invention.

[Effect]

In the flexible exhaust pipe of the present invention, in addition to the fact that the tip of the outer cylinder and the tip of the stay have a labyrinth structure as described above,
A cushioning material is attached to such a portion. For this reason, not only does it become difficult for rainwater, muddy water, salt water, etc. to adhere to the bellows pipe, but even if the bellows pipe bends while the car is being driven, noise is reduced due to the presence of the cushioning material.

The effect of the present invention will be made clearer from the following examples.

〔Example〕

FIG. 1 is a longitudinal sectional view of a flexible exhaust pipe according to a first embodiment of the present invention.

In FIG. 1, the flexible exhaust pipe 10 is
A bellows pipe 11, an outer cylinder 12 for protecting the bellows pipe 11 from flying stones, rainwater, salt water, etc., an inner cylinder 13 for reducing exhaust gas noise, and an exhaust gas outlet pipe 22.
It is composed of. Arrow G represents the flow of exhaust gas. Arrow Q indicates flexible exhaust pipe 1
0 represents the direction of travel of the car when it is attached to the car.

The outer cylinder 12 covers the bellows tube 11. Further, the inner cylinder 13 is arranged inside the bellows tube 11.
A certain amount of space is provided between the outer cylinder 12 and the bellows tube 11. In addition, the inner cylinder 13 and the bellows pipe 11
There is also a certain amount of space between them.

The inner cylinder 13 and the exhaust gas outlet pipe 22 have approximately the same diameter and are arranged coaxially. In addition, the inner cylinder 13
A certain distance is maintained between the exhaust gas outlet pipe 22 and the exhaust gas outlet pipe 22.

30 is an exhaust gas inlet, and 31 is an exhaust gas outlet. The exhaust gas inlet 30 is formed in the inner cylinder 13, and the exhaust gas outlet 31 is formed in the exhaust gas outlet pipe 2.
It is formed in 2.

As can be seen from FIG. 1, the tip portion 45 of the outer cylinder 12 extends to the vicinity of the exhaust gas outlet pipe 22. The tip portion 45 is an open end (ie, the opening 23). The opening 23 is opened toward the rear with respect to the direction of travel of the automobile (direction of arrow Q), and as mentioned earlier, this is to prevent rainwater, muddy water, salt water, etc. from entering.

At the exhaust gas inlet 30, the bellows pipe 11 and the outer cylinder 12 are both welded to the inner cylinder 13 at a portion designated by the reference numeral 32. The bellows pipe 11 and the exhaust gas outlet pipe 22 are welded together at a portion designated by reference numeral 33, that is, around the exhaust gas outlet 31. 39 is a ring for holding down the bellows tube 11.

Everything up until now is exactly the same as before.

As can be seen from FIG. 1, the flexible exhaust pipe 10 of the present invention is characterized in that the opening 23 of the outer cylinder 12 has a labyrinth structure and that a cushioning material 41 is attached to this part. There is. These will be explained in detail.

As can be seen from FIG. 1, the exhaust gas outlet pipe 22
An annular stay 42 is attached by welding at a portion designated by reference numeral 43. The tip 37 of the stay 42 extends to about the tip portion 45 of the outer cylinder 12.

A stopper 44 having an L-shaped cross section is welded to the stay 42. This stopper 44
It is arranged so as to cover the tip portion 45 of.

A cushioning material 41 is attached to the tip portion 45 of the outer cylinder 12. The buffer material 41 is attached to the tip portion 45 of the outer tube 12 so as to cover the tip portion 45 of the outer tube 12 . The material of the cushioning material 41 may be rubber, resin, wire net, asbestos, heat-resistant fiber, or the like.

Another thing to pay attention to in this embodiment is that, as can be seen from FIG. 1, a drain hole 38 is provided in the lower part of the outer cylinder 12.

The operation of this embodiment will be explained.

In the flexible exhaust pipe 10 of this embodiment, in addition to the opening 23 of the outer tube 12 having a labyrinth structure as described above, a buffer material 41 is attached to this portion. Therefore, not only does it become difficult for rainwater, muddy water, salt water, etc. to adhere to the bellows pipe 11, but even if the bellows pipe 11 bends in the direction of arrow A-B while driving the car, the cushioning material 11 prevents noise. becomes smaller.

Moreover, since the flexible exhaust pipe 12 of this embodiment is provided with a water drain hole 38, even if rainwater, muddy water, salt water, etc. should enter the outer cylinder 12, it will be easily drained from there.

FIG. 2 is a longitudinal sectional view of a flexible exhaust pipe according to a second embodiment of the present invention. The one in Figure 2 is
A bellows 51 for sealing is provided on the cushioning material 41 to make it even more difficult for rainwater, muddy water, salt water, etc. to enter than the one shown in FIG. Second
In the figure, 52 is a holding member for holding the cushioning material 41. The holding member 52 is welded to the inside of the outer cylinder 12.

The other matters regarding the flexible exhaust pipe 10 in FIG. 2 are exactly the same as those in FIG. 1, so the reference numerals are only added to the figure and further explanation will be omitted.

FIG. 3 is a longitudinal sectional view of a flexible exhaust pipe according to a third embodiment of the present invention. The one shown in FIG. 3 has a sealing membrane 53 attached to the buffer material 41 for sealing, making it even more difficult for rainwater, muddy water, salt water, etc. to enter than the one shown in FIG. The material for the sealing film 53 is preferably resin, glass fiber, or the like.

In FIG. 3, 52 is a holding member for holding the cushioning material 41. The holding member 52 is welded to the inside of the outer cylinder 12.

Other aspects of the flexible exhaust pipe 10 shown in FIG. 3 are exactly the same as those shown in FIG.

FIG. 4 is a longitudinal sectional view of a flexible exhaust pipe according to a fourth embodiment of the present invention. In FIG. 4, 52 is a holding member for holding the cushioning material 41. The holding member 52 is welded to the inside of the outer cylinder 12.

The one shown in Fig. 4 has an eaves 54 extending toward the rear of the vehicle (in the direction of arrow P) on the holding member 52, making it even more difficult for rainwater, muddy water, salt water, etc. to enter than the one shown in Fig. 1. be.

Other aspects of the flexible exhaust pipe 10 shown in FIG. 4 are exactly the same as those shown in FIG. 1, so the reference numerals are only added to the figure and further explanation will be omitted.

FIG. 5 is a longitudinal sectional view of a flexible exhaust pipe according to a fifth embodiment of the present invention. In the one shown in FIG. 5, a bellows 51 for sealing is provided on the cushioning material 41, making it even more difficult for rainwater, muddy water, salt water, etc. to enter than the one shown in FIG. Fifth
In the figure, the cushioning material 41 is attached to the tip portion 45 of the outer cylinder 12 in the same way as in FIG.

The other matters regarding the flexible exhaust pipe 10 in FIG. 5 are exactly the same as those in FIG. 1, so the reference numerals are only added to the figure and further explanation will be omitted.

FIG. 6 is a longitudinal sectional view of a flexible exhaust pipe according to a sixth embodiment of the present invention. In the one shown in FIG. 6, a labyrinth structure is constructed by extending an annular stay 42 to a position where it covers a buffer material 41 from the outside.

The other matters regarding the flexible exhaust pipe 10 in FIG. 6 are exactly the same as those in FIG. 1, so the reference numerals are only added to the figure and further explanation will be omitted.

FIG. 7 is a longitudinal sectional view of a flexible exhaust pipe according to a seventh embodiment of the present invention. The one in FIG. 7 has a cover 55 with a U-shaped cross section attached to the tip 45 of the annular stay 42 to cover the cushioning material 41 from both inside and outside, and is better than the one in FIG. 1. Furthermore, it is made even more difficult for rainwater, muddy water, salt water, etc. to penetrate.

The other details regarding the flexible exhaust pipe 10 in FIG. 7 are exactly the same as those in FIG. 1, so the reference numerals are only added to the figure and further explanation will be omitted.

FIG. 8 is a longitudinal sectional view of a flexible exhaust pipe according to an eighth embodiment of the present invention. In the case shown in FIG. 8, a holding member 56 having an L-shaped cross section is attached to the tip portion 45 of the outer cylinder 12.
A buffer material 41 having an L-shaped cross section is attached to the inside of the shock absorber 6, and an annular stay 42 is brought close to the buffer material 41 to form a labyrinth structure.

Other aspects of the flexible exhaust pipe 10 shown in FIG. 8 are exactly the same as those shown in FIG. 1, so the reference numerals are only added to the figure and further explanation will be omitted.

FIG. 9 is a longitudinal sectional view of a flexible exhaust pipe according to a ninth embodiment of the present invention. In the case shown in FIG. 9, a holding member 56 having a crank-shaped cross section is attached to the tip portion 45 of the outer cylinder 12, and a cushioning material 41 having an L-shaped cross-section is attached to the outside of the holding member 56.
is attached, and an annular stay 42 is brought close to the buffer material 41 to form a labyrinth structure.

The other matters regarding the flexible exhaust pipe 10 in FIG. 9 are exactly the same as those in FIG. 1, so the reference numerals are only added to the figure and further explanation will be omitted.

FIG. 10 is a longitudinal sectional view of a flexible exhaust pipe according to a tenth embodiment of the present invention. In the case shown in FIG. 10, a holding member 56 having a U-shaped cross section is attached to the tip 45 of the outer cylinder 12, and a cushioning material 41 having an L-shaped cross section is attached to the back side of the holding member 56. An annular stay 42 is brought close to a member 41 to form a labyrinth structure.

The other details regarding the flexible exhaust pipe 10 shown in FIG. 10 are exactly the same as those shown in FIG. 1, so the reference numerals are only added to the figure and further explanation will be omitted.

FIG. 11 is a longitudinal sectional view of a flexible exhaust pipe according to an eleventh embodiment of the present invention. In the case shown in FIG. 11, a holding member 56 having an L-shaped cross section is attached to the inside of the outer cylinder 12, and a cushioning material 41 having an L-shaped cross-section is attached to the inside of the holding member 56.
An annular stay 42 is brought close to a buffer material 41 to form a labyrinth structure.

Other details regarding the flexible exhaust pipe 10 shown in FIG. 11 are exactly the same as those shown in FIG. 1, so the reference numerals are only added to the figure and further explanation will be omitted.

FIG. 12 is a longitudinal sectional view of a flexible exhaust pipe according to a twelfth embodiment of the present invention. In the one shown in FIG. 12, a holding member 56 having an L-shaped cross section is attached to the inside of the outer cylinder 12, and a cushioning material 41 having an L-shaped cross-section is attached to the inside of the holding member 56.
An annular stay 42 having an L-shaped tip 37 is brought close to a buffer material 41 to form a labyrinth structure.

The other details regarding the flexible exhaust pipe 10 in FIG. 12 are exactly the same as those in FIG. 1, so the reference numerals are only added to the figure and further explanation will be omitted.

FIG. 13 is a longitudinal sectional view of a flexible exhaust pipe according to a thirteenth embodiment of the present invention. In the one shown in FIG. 13, a holding member 56 having an L-shaped cross section is attached to the tip portion 45 of the outer cylinder 12, and a buffer material 41 is attached to the tip of the holding member 56. Further, a stay 61 having a U-shaped cross section is attached around the exhaust gas outlet pipe 22. The U-shape of the stay 61 is open toward the outside in the radial direction. As can be seen from the figure, the one in FIG. 13 has a labyrinth structure by fitting the buffer material 41 into the stay 61.

Other details regarding the flexible exhaust pipe 10 shown in FIG. 13 are exactly the same as those shown in FIG. 1, so that only reference numerals are added to the figure and further explanation will be omitted.

FIG. 14 is a longitudinal sectional view of a flexible exhaust pipe according to a fourteenth embodiment of the present invention. In the one shown in FIG. 14, a holding member 56 having a crank-shaped cross section is attached to the tip portion 45 of the outer cylinder 12, and a buffer material 41 is attached to the tip of the holding member 56. In addition, the exhaust gas outlet pipe 22
A stay 61 having a U-shaped cross section is attached around the periphery. The U-shape of the stay 61 is open in the direction of travel of the automobile (direction of arrow Q). As can be seen from the figure, the one in FIG. 14 has a labyrinth structure by fitting the buffer material 41 into the stay 61.

Other details regarding the flexible exhaust pipe 10 shown in FIG. 14 are exactly the same as those shown in FIG. 1, so the reference numerals are only added to the figure and further explanation will be omitted.

FIG. 15 is a longitudinal sectional view of a flexible exhaust pipe according to a fifteenth embodiment of the present invention. In the one shown in FIG. 15, a holding member 56 having a U-shaped cross section is attached to the tip portion 45 of the outer cylinder 12, and a buffer material 41 is attached to the tip of the holding member 56. Further, a stay 61 having a U-shaped cross section is attached around the exhaust gas outlet pipe 22. The U-shape of the stay 61 opens toward the rear of the automobile (in the direction of arrow P). As can be seen from the figure, the one in Fig. 15 has a cushioning material 4 inside the stay 61.
1 is inserted to form a labyrinth structure.

The other matters regarding the flexible exhaust pipe 10 in FIG. 15 are exactly the same as those in FIG. 1, so the reference numerals are only added to the figure and further explanation will be omitted.

FIG. 16 is a longitudinal sectional view of a flexible exhaust pipe according to a sixteenth embodiment of the present invention. In the one shown in FIG. 16, a holding member 56 having a U-shaped cross section is attached to the tip portion 45 of the outer cylinder 12, and a buffer having a U-shaped cross section is installed inside the holding member 56. A material 41 is attached. Holding member 5
The U-shape of 6 is open toward the center in the radial direction. As can be seen from the figure, the one in FIG. 16 has a labyrinth structure in which the stay 42 is fitted into the buffer material 41.

Other details regarding the flexible exhaust pipe 10 shown in FIG. 16 are completely the same as those shown in FIG. 1, so that only the reference numerals are added to the figure and further explanation will be omitted.

FIG. 17 is a longitudinal sectional view of a flexible exhaust pipe according to a seventeenth embodiment of the present invention. In the one shown in FIG. 17, a holding member 56 having a U-shaped cross section is attached to the tip portion 45 of the outer cylinder 12, and a buffer having a U-shaped cross section is installed inside the holding member 56. A material 41 is attached. Holding member 5
The U-shape number 6 is open in the direction of travel of the car (direction of arrow Q). Further, the tip 37 of the annular stay 42 is bent into an L-shape. 17th
As can be seen from the figure, the tip 37 of the stay 42 is fitted into the buffer material 41 to form a labyrinth structure.

The other details regarding the flexible exhaust pipe 10 in FIG. 17 are exactly the same as those in FIG. 1, so the reference numerals are only added to the figure and further explanation will be omitted.

FIG. 18 is a longitudinal sectional view of a flexible exhaust pipe according to the 18th embodiment of the present invention. In the one shown in FIG. 18, a holding member 56 having a U-shaped cross section is attached to the tip portion 45 of the outer cylinder 12, and a buffer having a U-shaped cross section is installed inside the holding member 56. A material 41 is attached. Holding member 5
The U-shape number 6 is open toward the rear of the car (in the direction of arrow P). As shown in FIG. 18, the tip 3 of the stay 42 is inside the cushioning material 41.
7 is fitted, creating a labyrinth structure.

Other details regarding the flexible exhaust pipe 10 shown in FIG. 18 are completely the same as those shown in FIG. 1, so that only the reference numerals are added to the figure and further explanation will be omitted.

FIG. 19 is a longitudinal sectional view of a flexible exhaust pipe according to a nineteenth embodiment of the present invention. In the case shown in FIG. 19, the cushioning material 41 is made of a flexible member. The material for the buffer material 41 is preferably resin or metal.

Other details regarding the flexible exhaust pipe 10 shown in FIG. 19 are exactly the same as those shown in FIG. 1, so the reference numerals are only added to the figure and further explanation will be omitted.

FIG. 20 is a longitudinal sectional view of a flexible exhaust pipe according to a twentieth embodiment of the present invention. In the one shown in FIG. 20, the cushioning material 41 is made of a flexible member, and an eaves 72 extending rearward (in the direction of arrow P) is provided. The material for the buffer material 41 is preferably resin or metal.

Other details regarding the flexible exhaust pipe 10 shown in FIG. 20 are exactly the same as those shown in FIG. 1, so that only the reference numerals are added to the figure and further explanation will be omitted.

[Effect of idea]

As can be seen from the description of the above embodiments, according to the present invention, in addition to making it difficult for rainwater, muddy water, salt water, etc. to adhere to the bellows pipe in a flexible exhaust pipe, noise caused by collision of the outer cylinder can be further reduced. This has the effect of reducing the amount of water.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a flexible exhaust pipe according to a first embodiment of the present invention, FIG. 2 is a vertical cross-sectional view of a flexible exhaust pipe according to a second embodiment of the present invention, and FIG. , FIG. 4 is a longitudinal cross-sectional view of a flexible exhaust pipe according to a fourth embodiment of the present invention, and FIG. 5 is a longitudinal cross-sectional view of a flexible exhaust pipe according to a fourth embodiment of the present invention. FIG. 6 is a vertical cross-sectional view of a flexible exhaust pipe according to a fifth embodiment of the present invention; FIG. 7 is a longitudinal cross-sectional view of a flexible exhaust pipe according to a sixth embodiment of the present invention; FIG. FIG. 8 is a longitudinal cross-sectional view of a flexible exhaust pipe according to an eighth embodiment of the present invention, and FIG. 9 is a longitudinal cross-sectional view of a flexible exhaust pipe according to a ninth embodiment of the present invention. FIG. 10 is a vertical cross-sectional view of a flexible exhaust pipe according to a tenth embodiment of the present invention, and FIG. 11 is a vertical cross-sectional view of a flexible exhaust pipe according to an eleventh embodiment of the present invention. 12 is a longitudinal sectional view of a flexible exhaust pipe according to a 12th embodiment of the present invention, and FIG. 13 is a longitudinal sectional view of a flexible exhaust pipe according to a 13th embodiment of the present invention. FIG. 14 is a vertical sectional view of a flexible exhaust pipe according to a fourteenth embodiment of the present invention, and FIG. 15 is a longitudinal sectional view of a flexible exhaust pipe according to a fifteenth embodiment of the present invention.
FIG. 6 is a vertical cross-sectional view of a flexible exhaust pipe according to a sixteenth embodiment of the present invention, and FIG. 17 is a longitudinal cross-sectional view of a flexible exhaust pipe according to a sixteenth embodiment of the present invention.
A vertical cross-sectional view of a flexible exhaust pipe according to an embodiment of
FIG. 18 is a vertical sectional view of a flexible exhaust pipe according to the 18th embodiment of the present invention, FIG. 19 is a vertical sectional view of the flexible exhaust pipe according to the 19th embodiment of the present invention, and FIG. , a vertical cross-sectional view of a flexible exhaust pipe according to the 20th embodiment of the present invention, FIG. 21 is an overall view of an automobile exhaust system showing the mounting position of the flexible exhaust pipe, and FIG. 22 is a conventional flexible exhaust pipe. FIG. FIG. 23 is a longitudinal sectional view of another conventional flexible exhaust pipe (flexible exhaust pipe disclosed in Japanese Utility Model Application No. 60-40885). 10... Flexible exhaust pipe, 11... Bellows pipe, 12... Outer tube, 13... Inner tube, 22... Exhaust gas outlet pipe, 30... Exhaust gas inlet, 31... Exhaust gas outlet, 41... Cushioning material, 42...stay.

Claims (1)

[Claims for Utility Model Registration] A flexible bellows tube, an outer tube covering the outside of the bellows tube, an inner tube disposed inside the bellows tube, and a combination of the inner tube and the bellows tube. and an exhaust gas outlet pipe arranged coaxially with the inner cylinder with a predetermined distance therebetween, and one end of the bellows pipe is welded to the inner cylinder and serves as an exhaust gas inlet. The other end of the bellows pipe is welded to the exhaust gas outlet pipe to serve as an exhaust gas outlet, and one end of the outer tube is a flexible exhaust pipe welded to the bellows pipe at the exhaust gas inlet. A stay is attached to the exhaust gas outlet pipe, the tip of the outer cylinder and the tip of the stay are arranged close to each other and have a labyrinth structure, and the tip of the outer cylinder and a tip portion of the stay, at least one of which is provided with a cushioning material for cushioning impact.