JPH0724577Y2 - Drainage structure of exhaust gas exhaust pipe for silencer - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to an improvement of a water draining structure in an exhaust gas outlet pipe of a silencer used in an exhaust system of an internal combustion engine.

[Conventional technology]

Exhaust gas derivation, which is generally L-shaped at the end of the silencer, is used in the exhaust system of internal combustion engines used for vehicles such as forklifts, hydraulic or pneumatic pressure generators used in civil engineering work, power generators, etc. The tube is attached.

Since this pipe end of this exhaust gas outlet pipe stands up,
Rainwater will come in from the pipe end.

Therefore, conventionally, as disclosed in, for example, Japanese Utility Model Laid-Open No. 63-118, a drainage is provided to remove the invading water.

This will be described with reference to FIGS. 4 and 5. Reference numeral 1 denotes a silencer, the upstream side of which is connected to an internal combustion engine (not shown) via an exhaust pipe 2. And on the downstream side of this silencer 1,
An exhaust gas lead-out pipe 3 having a substantially L shape is attached.

The exhaust gas lead-out pipe 3 has a tubular body 4 protruding in the horizontal direction.
It is formed by welding the tube body 5 standing upright substantially vertically from the end of the tube body 4. And the tubular body 4
A small hole 6 for draining water is formed at the bottom of the.

According to the drainage structure of the exhaust gas outlet pipe for the silencer thus configured, the end portion of the pipe body 5 forming the exhaust gas outlet pipe 3
51 is opened to the outside air, the exhaust gas discharged from the internal combustion engine is silenced by the silencer 1, and after the sound pressure is reduced, the exhaust gas is discharged from the end portion 51 of the pipe body 5.

Then, the rainwater or the like that has entered from the end portion 51 of the pipe body 5 is discharged from the drainage small hole 6 formed in the bottom portion of the pipe body 4 that constitutes the exhaust gas discharge pipe 3. Has become.

[Problems to be solved by the device]

However, the conventional drainage structure of the exhaust gas lead-out pipe for a muffler has a small hole 6 for draining formed in the bottom of the pipe body 4.
Since it is drained from the inside, it is easy to prevent the accumulated rainwater and the like from dripping due to the surface tension, and the drainage function cannot be sufficiently exerted. As a result, rainwater or the like collected in the exhaust gas discharge pipe 3 penetrates the exhaust gas discharge pipe 3 and enters the silencer 1, and is contaminated by soot and the like in the silencer 1 and exhaust gas at the initial stage of the operating state. There was such a problem that it was blown out together with it to stain the surroundings, or it stayed in the silencer 1 and corroded the silencer 1.

The present invention has been made to solve such conventional problems, and an object thereof is to provide a drainage structure of a muffler exhaust gas discharge pipe capable of reliably discharging invading rainwater and the like. To provide.

[Means for Solving the Problems]

The drainage structure of the exhaust gas outlet pipe for the muffler according to the present invention is
In the drainage structure of the exhaust gas outlet pipe for the muffler, the exhaust gas outlet pipe having a substantially L-shape with a drain on the bottom is attached to the end of the silencer so that the pipe end stands up. While forming an exhaust gas lead-out pipe with a first tubular body that projects horizontally from the end of the container and a substantially L-shaped second tubular body that has a tubular diameter larger than this first tubular body, The end of the second tubular body is superposed and fixed to the upper side wall surface of the first tubular body so that the downstream side stands upright, and a drainage passage is formed in the gap between the first tubular body and the second tubular body. It consists of

[Action]

In the present invention, when rainwater or the like enters from the opening end of the second pipe body, the rainwater or the like is passed through the drainage passage formed in the gap between the first pipe body and the second pipe body. It can be discharged to the outside through

Also, during operation, outside air can enter through the water drain passage formed in the gap between the first pipe body and the second pipe body, and the exhaust gas temperature can be lowered.

〔Example〕

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

FIG. 1 shows a structure for draining an exhaust gas outlet pipe for a silencer according to an embodiment of the present invention, and 10 denotes a silencer.

The silencer 10 has an exhaust pipe 11 on the upstream side of an internal combustion engine (not shown).
Are connected via. An exhaust gas outlet pipe 12 having a substantially L shape is attached to the downstream side of the silencer 10.

The exhaust gas lead-out pipe 12 is substantially L-shaped with the first pipe body 13 protruding horizontally from the end portion of the silencer 10, and has a pipe diameter larger than that of the first pipe body 13. It is formed by the body 14. Then, the second pipe body 14 covers the inner side 17 of the upstream end portion 16 on the upper side wall surface 18 of the first pipe body 13 so that the downstream side 15 stands upright, and the portion is fixed by welding. . Therefore, the end portion 151 on the downstream side 15 of the second pipe body 14 forming the exhaust gas outlet pipe 12 is open to the outside air.

Due to the joining of the first tubular body 13 and the second tubular body 14, a gap having a substantially crescent-shaped cross section between the first tubular body 13 and the second tubular body 14.
19 is formed, and the gap 19 is sized so as to function as the drainage passage 20.

Next, the function and effect of this embodiment thus configured will be described.

The end portion 151 on the downstream side 15 of the second pipe body 14 that constitutes the exhaust gas outlet pipe 13 is open to the outside air, so rainwater and the like enter from there regardless of the operating state or the stopped state. The rainwater or the like that has infiltrated drops downward through the wall surface or the internal space of the first pipe body 13 forming the exhaust gas discharge pipe 12,
It moves to the crescent-shaped gap 19 between the first pipe body 13 and the second pipe body 14 which form the exhaust gas discharge pipe 12, that is, the drainage passage 20. Since this drainage passage 20 is formed by a crescent-shaped gap 19 in cross section, rainwater or the like is less subject to resistance due to surface tension as compared with a round hole, and its circulation is not hindered. . Therefore, rainwater and the like flowing into the drainage passage 20 can be easily discharged to the outside.

Further, the exhaust gas discharged from the internal combustion engine is silenced by the silencer 10, the sound pressure is reduced, and then flows into the exhaust gas outlet pipe 12 attached to the end portion of the silencer 10. At this time, the first pipe body 13 and the second pipe body that form the exhaust gas discharge pipe 12
Since there is a gap 19 between 14 and
The outside air is sucked from 19 and mixed with the flowing exhaust gas to lower the temperature of the exhaust gas. Then, the exhaust gas is discharged from the end portion 151 of the second pipe body 14 on the downstream side 15.

As described above, according to this embodiment, rainwater or the like that has entered from the end portion 151 of the downstream side 15 of the second pipe body 14 that constitutes the exhaust gas outlet pipe 12 constitutes the exhaust gas outlet pipe 12. A crescent-shaped gap 19 between the first pipe body 13 and the second pipe body 14, that is, a drainage passage 20.
There is no longer any discharge to the outside through the drainage passage 20 and the inflow to the first pipe body 13 forming the exhaust gas lead-out pipe 12. Therefore, rainwater accumulated in the exhaust gas outlet pipe 12 does not flow into the muffler 10, is contaminated by soot and the like in the muffler 10, and is blown out together with the exhaust gas at the beginning of the operating state to the surroundings. Problems such as soiling the inside of the muffler 10 and remaining inside the muffler 10 to corrode the inside of the muffler 10 are solved.

Further, the first pipe body 13 and the second pipe body that form the exhaust gas discharge pipe 12
The crescent-shaped gap 19 with respect to 14, that is, the drainage passage 20 forms an opening communicating with the outside air in the middle of the exhaust gas outlet pipe 12, and therefore functions as a device for introducing the outside air according to the exhaust gas flow velocity. As a result, it becomes possible to positively cool the exhaust gas and improve the sound deadening performance.

FIG. 3 shows another embodiment of the present invention.
A slit (21) is provided at the upstream end (16) to increase the welding length with the first tubular body (13).

According to this embodiment, in addition to exhibiting the same effect as the above embodiment, since the number of welded portions between the first pipe body 13 and the second pipe body 14 is increased, the joint strength between both is improved, It becomes possible to give more durability as compared with the example.

Incidentally, in order to improve the joint strength, it is possible to use plug welding or the like.

[Effect of device]

As described above, according to the present invention, a substantially L-shaped exhaust gas outlet pipe having a drainage at the bottom is attached to the end portion of the silencer so that the pipe end stands up. In the water draining structure of No. 1, the first tube body that horizontally protrudes from the end of the silencer and the second tube body that is substantially L-shaped and has a tube diameter larger than this first tube body. While forming the exhaust gas outlet pipe, the end portion of the second pipe body is superposed and fixed to the upper side wall surface of the first pipe body so that the downstream side stands up, and the gap between the first pipe body and the second pipe body Since the water drainage passage is formed in the interior, it is possible to reliably discharge the invading rainwater and the like, and the risk of infiltrating rainwater and the like into the muffler is reduced, and when starting the internal combustion engine It is possible to prevent water from blowing out. or,
The drainage passage serves as an outside air introduction port during operation, the exhaust gas temperature can be lowered, and the sound deadening performance can be improved.

[Brief description of drawings]

FIG. 1 is a side view showing a drainage structure of an exhaust gas outlet pipe for a silencer according to an embodiment of the present invention. FIG. 2 is an enlarged vertical sectional view taken along the line II-II in FIG. FIG. 3 is a top view showing a drainage structure of an exhaust gas outlet pipe for a silencer according to another embodiment of the present invention. FIG. 4 is a side view showing a conventional drainage structure of an exhaust gas outlet pipe for a silencer. FIG. 5 is a bottom view showing the water draining structure of the silencer exhaust gas lead-out pipe shown in FIG. 4. [Explanation of symbols of main parts] 10 …… Silencer 12 …… Exhaust gas outlet pipe 13 …… First pipe 14 …… Second pipe 15 …… Downstream side of second pipe 14 ………… The upstream end portion of the two pipes 18 ... the upper side wall surface of the first pipe 13 19 ... the gap 20 ... a drainage passage.

Claims (1)

[Scope of utility model registration request] 1. A water drainage structure for a muffler exhaust gas lead-out pipe, comprising a substantially L-shaped exhaust gas lead-out pipe provided with a water drain at the bottom and attached to the end of the muffler so that the pipe end stands upright. In the above, the first tubular body protruding horizontally from the end of the silencer,
The exhaust gas lead-out pipe is formed with a second pipe having a substantially L-shape and a pipe diameter larger than that of the first pipe, and the end portion of the second pipe is formed so as to stand upright on the downstream side. A drainage structure for an exhaust gas outlet pipe for a silencer, characterized in that the drainage passage is formed in the gap between the first pipe body and the second pipe body by being superposed and fixed on the upper side wall surface of the pipe body. .