JP2005330830A - Muffler - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new muffler further improving discharge of condensed water from an outlet pipe by effectively evaporating condensed water collected in the muffler chamber with using exhaust heat of exhaust gas led in the muffler chamber. <P>SOLUTION: In the muffler provided with a muffling chamber CH, an inlet pipe 10 leading exhaust gas to the muffling chamber CH, and the outlet pipe 20 discharging exhaust gas from the muffling chamber CH to an outside, the inlet pipe 10 is provided roughly in parallel with a bottom wall Cb with making an inside of the muffling chamber CH close to the bottom wall Cb, and a part thereof touches condensed water W stored in the muffling chamber CH. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a silencer connected to an exhaust system of an engine, and more particularly to an improvement of a silencer that can promote the discharge of condensed water stored in the bottom of the silencer to the outside.

Conventionally, a silencer connected to an exhaust system of a vehicle engine such as an automobile exhausts the exhaust gas silenced in the noise reduction chamber, an inlet pipe that leads exhaust gas from the engine to the noise reduction chamber, and the silencer. In such a silencer, when the exhaust gas led from the inlet pipe to the silencer chamber is cooled while flowing through the silencer chamber, moisture contained therein is removed. Condensed and separated into condensed water, which accumulates at the bottom of the silencer chamber, which causes corrosion of the silencer chamber, and various technical means have been proposed to discharge this condensed water to the outside through the outlet pipe. For example, in Patent Document 1 described later, the opening surface of the opening in the silencer chamber of the tail pipe (outlet pipe) is close to the bottom surface of the silencer chamber. Only, which discharge of condensed water from the tailpipe has to be accelerated is disclosed.
Japanese Utility Model Publication No. 56-46023

  However, as disclosed in Patent Document 1, even if the opening of the tail pipe (outlet pipe) is brought close to the bottom of the silencer, the condensed water is sufficiently discharged only by the momentum of the exhaust gas exhaust flow. There is a problem that can not be.

  The present invention has been made in view of such circumstances, and condensate water from an outlet pipe is effectively vaporized by using the exhaust heat of the exhaust gas guided into the silencer chamber to effectively vaporize the condensed water. It aims at providing the new silencer which improved discharge | emission of this.

  In order to achieve the above object, the invention according to claim 1 is a silencer comprising a silencer chamber, an inlet pipe for leading exhaust gas to the silencer chamber, and an outlet pipe for exhausting exhaust gas from the silencer chamber to the outside. In the inlet pipe, at least a part of the inlet pipe is provided close to the bottom wall of the silencer chamber and substantially parallel to the bottom wall, and is in contact with the condensed water stored in the silencer chamber. It is a feature.

  In order to achieve the object, the invention according to claim 2 is the one according to claim 1, wherein the opening end of the inlet pipe in the silencer chamber is more open than the opening end of the outlet pipe in the silencer chamber. Is also characterized by being placed at the top.

  Furthermore, in order to achieve the object, the invention according to claim 3 is the one according to claim 1 or 2, wherein the inlet pipe is both supported by the end plate of the silencer chamber and the partition plate in the silencer chamber. It is characterized by being supported.

  According to the first aspect of the present invention, the inlet pipe that guides the high-temperature exhaust gas from the engine into the silencer chamber contacts the condensed water accumulated at the bottom of the silencer chamber and heats the condensed water. The temperature rises and vaporization of the condensed water is promoted. The vaporized condensed water is easily discharged from the outlet pipe together with the exhaust flow, so that the condensed water is relied only on the momentum of the exhaust gas exhaust flow as disclosed in Patent Document 1. Compared with what was made to discharge | emit, the discharge | emission of the condensed water collected in the bottom part of the silencer is improved significantly.

  According to the second aspect of the present invention, since the opening end of the inlet pipe is positioned higher than the opening end in the silencer chamber C of the outlet pipe, the condensed water in the silencer chamber is There is no backflow into the pipe.

  Furthermore, according to the third aspect of the present invention, the inlet pipe is supported at both ends by the end plate of the silencer chamber and the partition plate in the silencer chamber, so that the support rigidity of the inlet pipe is increased, and the condensed water is increased. Even if the inlet pipe is formed long in order to further promote vaporization, the support rigidity is not lowered.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below based on examples of the present invention illustrated in the accompanying drawings.

  In this embodiment, the silencer of the present invention is applied to the exhaust system of an automobile engine. FIG. 1 is a schematic plan view of the exhaust system of the engine equipped with the silencer of the present invention, and FIG. FIG. 3 is a sectional view taken along line 3-3 in FIG. 2, FIG. 4 is a sectional view taken along line 4-4 in FIG. 3, and FIG. FIG. 5 is a cross-sectional view taken along line 5-5.

  In FIG. 1, an exhaust system Ex for exhausting exhaust gas exhausted by the operation to the atmosphere is connected to an automobile engine, which is generally indicated by E. The exhaust system Ex is connected to an exhaust manifold Mf connected to an exhaust port of the engine E and an exhaust pipe 1 connected to a downstream end thereof in order from the upstream side to the downstream side, and includes a catalyst Ca and a prechamber. P and a silencer M are provided.

  Then, the exhaust gas discharged from the engine E is purified by the catalyst Ca, the primary component is silenced by the pre-chamber P, the secondary noise is silenced by the silencer M, and the exhaust gas is discharged to the atmosphere.

  Next, the structure of the silencer M according to the present invention will be described in detail with reference to FIGS.

  When the exhaust system Ex is connected to the engine E, the silencer M is arranged with an inclination angle θ with respect to a horizontal plane so as to take a slightly inclined posture as shown in FIG. The condensed water W collected in the muffler chamber CH is collected at the front part thereof.

  The shell 2 constituting the casing of the sound deadening chamber M is made of stainless steel, and the shell main body 2a formed in the shape of an elliptic cylinder, and the rear end plates 2b and 2c before and after being airtightly caulked and fixed to the front and rear opening ends. And is formed in a sealed hollow elliptical cylindrical shape. And this shell 2 is arrange | positioned toward the up-down direction on the short diameter side. The exhaust pipe 1 extending from the pre-chamber P is connected to the front end plate 2b of the shell 2, and the tail pipe 9 opening to the atmosphere is connected to the rear end plate 2c in an airtight manner.

  In the muffler chamber CH defined by the shell 2, the first partition plate 3 and the second partition plate 4 are substantially parallel to the front and rear end plates 2b and 2c with a space in the longitudinal direction. The first expansion chamber 5 is formed by the first partition plate 3 and the second partition plate 4 in the middle portion in the longitudinal direction of the shell 2, and the first expansion chamber 5 The second expansion chamber 6 is formed by the front end plate 2 b and the first partition plate 3 on the front side of the first expansion chamber 5, and the second partition plate 4 is formed on the rear side of the first expansion chamber 5. A resonance chamber 7 is formed by the rear end plate 2c. Therefore, the silencing chamber CH is partitioned into a first expansion chamber 5, a second expansion chamber 6 and a resonance chamber 7.

  As shown in FIG. 4, a plurality of communication holes 15, 16, 17 are opened in the first partition plate 3 at intervals, and the first partition plate 3 is connected to the first partition plate 3 via the communication holes 15, 16, 17. The expansion chamber 5 and the second expansion chamber 6 are in communication with each other. In addition, as shown in FIG. 5, the second partition plate 4 has a plurality of small holes 18, and the second expansion chamber 5 and the resonance chamber 7 communicate with each other through the small holes 18. Has been.

  2 and 3, the rear end (downstream end) of the exhaust pipe 1 through which the exhaust gas from the pre-chamber P is guided straddles the first and second expansion chambers 5 and 6 in the silencer chamber CH. The front end (upstream end) of the inlet pipe 10 disposed in this manner is connected in communication. The inlet pipe 10 is close to the bottom wall Cb of the muffling chamber CH, and has a base portion 10a extending across the first and second expansion chambers 5 and 6 substantially parallel to the bottom wall Cb, and the base portion 10a. It is formed in an L-shape with a tip portion 10b that is bent and extended upward at a substantially right angle from the rear end portion (downstream side portion), and the base end of the base portion 10a is penetrated and supported by the front end plate 2b of the shell 2, Further, the intermediate portion of the base portion 10a is supported through the support hole 13 formed in the first partition plate 3, that is, the base portion 10a of the inlet pipe 10 is supported at both ends by the silencer chamber CH. Even if the ten base portions 10a are formed long, high support rigidity of the inlet pipe 10 is ensured.

  The opening end portion of the tip portion 10b of the inlet pipe 10 is directed upward in the silencing chamber CH, and the opening surface thereof is substantially parallel to the bottom wall Cb of the silencing chamber CH. And this opening end part is located higher than the opening end part in the silencer chamber CH of the outlet pipe 20 mentioned later, and the condensed water in the silencer chamber CH flows back into the inlet pipe 10 so that it may mention later. There has been no such thing.

  The high-temperature exhaust gas guided from the exhaust pipe 1 to the inlet pipe 10 is discharged upward in the first expansion chamber 5 of the sound deadening chamber CH. Then, as will be described later, the base 10a of the inlet pipe 10 heated by the exhaust gas comes into contact with the condensed water accumulated in the muffler chamber CH, and the condensed water is heated by the inlet pipe 10 and vaporized. it can.

  As shown in FIGS. 2 and 3, a relatively short communication pipe 11 is supported on the second partition plate 4 substantially in parallel with the axis of the shell 2, and the communication pipe 11 has a first expansion. The chamber 5 and the resonance chamber 7 are in communication with each other, and exhaust gas in the first expansion chamber 5 is guided to the resonance chamber 7.

  An outlet pipe 20 is disposed in the shell 2 in parallel with the inlet pipe 10. The outlet pipe 20 as a whole is bent in an S shape along the longitudinal direction of the shell 2 and is extended long, and each of the outlet pipes 20 has a straight shape, and each has an exhaust gas inlet pipe portion 21, a return direction pipe portion 22, and an exhaust gas. The discharge pipe portion 23 is composed of two upstream and downstream direction changing pipe portions 24 and 25 that connect them together, and is bent twice.

  As clearly shown in FIG. 2, the straight exhaust gas inlet pipe portion 21 is disposed on one side of the bottom of the shell 2 in parallel with the axis of the shell 2, and the first and second partition plates 3. , 4 are supported through the support holes 26 and 29 opened in the center. The opening end of the front end (upstream end) is expanded in a divergent shape and opened in the second expansion chamber 6, and the rear end (downstream end) is in the resonance chamber 7, It is connected to the upstream direction change pipe section 24. The exhaust gas introduction pipe portion 21 is arranged at the bottom of the shell 2, thereby facilitating introduction of the exhaust flow containing the vaporized condensed water in the shell 2 into the outlet pipe 20.

  Further, as clearly shown in FIG. 3, the return pipe portion 22 is located in the upper part of the shell 2, is located at the center in the left-right direction, and is arranged in parallel with the axis of the shell 2. The first and second partition plates 3 and 4 are supported through the support holes 27 and 30 opened. And the rear end (upstream end) is in the resonance chamber 7 and is connected to the upstream direction change pipe portion 24, and the front end (downstream end) is in the second expansion chamber 6, It is connected to the downstream direction change pipe section 25.

  Further, as clearly shown in FIG. 3, the exhaust gas discharge pipe portion 23 is located at a substantially central portion in the left-right direction at the lower portion in the shell 2 and is disposed in parallel with the axis of the shell 2. The first and second partition plates 3 and 4 and the rear end plate 2c are supported through the support holes 28, 31 and 32. The front end (upstream end) is in the second expansion chamber 6 and is connected to the downstream direction change pipe portion 25, and the rear end (downstream end) is opened to the atmosphere. It is connected to the.

  As shown in FIGS. 4 and 5, the three pipe parts constituting the outlet pipe 20, that is, the exhaust gas inlet pipe part 21, the return direction pipe part 22, and the exhaust gas discharge pipe part 23 are substantially parallel to each other. These are arranged in parallel along the longitudinal direction of the shell 2.

  As shown in FIG. 3, an exhaust sound interference hole 34 made up of a large number of small holes is opened in the upper region of the return pipe portion 22 corresponding to the first expansion chamber 5. The exhaust sound interference hole 34 has a function of effectively preventing resonance of exhaust sound of the exhaust gas flowing through the long outlet pipe 20.

  As shown in FIG. 3, the lowermost portions of the first partition plate 3 and the second partition plate 4 are provided with water passage holes 36 and 37 that allow the front and rear to communicate with each other. Since the shell 2 is slightly forward tilted as described above, the water is collected at the front bottom in the shell 2 through the water passage holes 36 and 37.

  Next, the operation of this embodiment will be described.

  Now, the engine E is operated, and the exhaust gas discharged therefrom is guided to the exhaust system Ex. The exhaust gas flowing through the exhaust system Ex enters the silencer M, where main exhaust noise is silenced.

  By the way, when the high-temperature exhaust gas that has flowed into the silencer M is cooled in the silencer chamber CH, the moisture contained therein is dewed to become condensed water, and the shell 2 is inclined forward in this condensed water. As a result, the water passes through the water passage holes 37 and 36 and accumulates at the front portion of the sound deadening chamber CH, that is, at the bottom portion in the second expansion chamber 6. The exhaust gas is heated by contact with the inlet pipe 10 through which the exhaust gas flows, is vaporized, and is efficiently discharged to the outside through the outlet pipe 20.

  As shown by an arrow A in FIG. 2, the exhaust gas discharged from the engine E is guided into the sound deadening chamber CH through the inlet pipe 10. As shown in FIG. 3, the base 10a of the inlet pipe 10 extends in the vicinity of the bottom wall Cb of the silencing chamber CH substantially in parallel with the bottom wall Cb, and is brought into contact with the condensed water accumulated at the bottom of the silencing chamber CH. Therefore, the inlet pipe 10 heated by the high-temperature exhaust gas can heat the condensed water and vaporize at an early stage. In this case, since the base portion 10a of the inlet pipe 10 extends over the first and second expansion chambers 5 and 6 and extends substantially in parallel with the bottom wall Cb of the silencer chamber CH, the condensed water in the silencer chamber CH The contact area can be increased and vaporization of condensed water is further promoted.

  And the exhaust flow containing the vaporized condensed water is discharged out of the silencer M from the outlet pipe 20 while the exhaust sound is attenuated. That is, the exhaust flow together with the vaporized condensed water enters the first expansion chamber 5 from the second expansion chamber 6 through the communication holes 15, 16, 17, and further passes through the communication tube 11 from the resonance chamber 7. The exhaust vibration energy is effectively attenuated by the combined action of exhaust expansion and resonance, and the primary exhaust noise is silenced. The exhaust flow in the resonance chamber 7 enters the first expansion chamber 5 through the plurality of small holes 18, and further passes through the communication holes 15, 16, 17 of the first partition plate 3 to form the second expansion. Enter room 6. The exhaust flow merged in the second expansion chamber 6 flows into the outlet pipe 20 from the opening end of the exhaust gas entry pipe portion 21 as indicated by an arrow B in FIG. As described above, the outlet pipe 20 is bent in a S-shape so as to be extended for a long time. As a result, the exhaust sound in the outlet pipe 20 is further attenuated while flowing through the pipe 20. The noise reduction is effectively performed secondarily. Then, the exhaust flow including the vaporized condensed water that has been sufficiently silenced is discharged to the atmosphere from the rear end of the exhaust gas discharge pipe portion 23 through the tail pipe 9 as shown by an arrow C in FIG. .

  In the above-described exhaust flow process, the opening end of the tip 10b of the inlet pipe 10 in the silencing chamber CH is positioned higher than the opening end of the outlet pipe 20 in the silencing chamber CH. Condensed water does not flow back into the inlet pipe 10. In addition, the inlet pipe 10 can be supported at both ends by the front end plate 2b and the first partition plate 3 of the sound deadening chamber CH so as to be supported at both ends by the sound deadening chamber CH, and the support rigidity thereof can be increased. Even if the inlet pipe 10 is formed long in order to further promote the vaporization of the condensed water, the support rigidity is not lowered. As described above, the condensed water accumulated in the sound deadening chamber CH is heated and vaporized by contact with the inlet pipe 10 through which the high-temperature exhaust gas flows, and the vaporized condensed water passes through the outlet pipe 20 together with the exhaust flow. Even if condensed water remains without being vaporized at that time, the accumulated condensed water is collected because the exhaust gas inlet pipe portion 21 is located near the bottom of the muffler chamber CH. Is easily discharged.

  Note that the condensed water is cooled in the shell 2 by the high-temperature exhaust gas, and moisture contained therein is dewed and enters the outlet pipe 20 outside the water that is condensed and accumulated in the shell 2 and during car washing. Also includes water accumulated in the shell 2.

  As mentioned above, although the Example of this invention was described, this invention is not limited to the Example, A various Example is possible within the scope of the present invention.

  For example, in the above-described embodiment, the case where the silencer of the present invention is implemented in the exhaust system of an automobile engine has been described, but it is needless to say that this can also be implemented in the exhaust systems of other engines. Moreover, in the said Example, although the edge part opening of the front part of an inlet pipe is orient | assigned upwards in the noise reduction room, if the opening edge part is higher than the opening edge part in the noise reduction room of an outlet pipe , It may be oriented in any direction.

Schematic plan view of an exhaust system of an engine equipped with the silencer of the present invention Transverse plan view of the silencer along line 2-2 in FIG. Sectional view along line 3-3 in FIG. Sectional view along line 4-4 in FIG. Sectional drawing which follows the 5-5 line of FIG.

Explanation of symbols

2b ... End plate (front end plate)
3 ... Partition plate (first partition plate)
10 ·············· Inlet pipe 20 ································································· ..... condensed water

Claims (3)

In a silencer comprising a silencing chamber (CH), an inlet pipe (10) for guiding exhaust gas to the silencing chamber (CH), and an outlet pipe (20) for exhausting exhaust gas from the silencing chamber (CH) to the outside ,
At least a part of the inlet pipe (10) is provided substantially parallel to the bottom wall (Cb) so that the inside of the silencing chamber (CH) is close to the bottom wall (Cb). A silencer, wherein the silencer is in contact with stored condensed water (W).   The opening end in the silence chamber (CH) of the inlet pipe (10) is arranged higher than the opening end in the silence chamber (CH) of the outlet pipe (10), The muffler according to claim 1. The said inlet pipe (10) is both-end-supported by the end plate (2b) of a silencing chamber (CH), and the partition plate (3) in a silencing chamber (CH), The said Claim 1 characterized by the above-mentioned. 2. The silencer according to 2.

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