JP2006152996A - Silencer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a silencer which makes it possible to set high the height above ground of a vehicle by making a silencer to be of flat section without entailing the increase in back pressures, as well as being superior in space-saving, low cost and silencing properties. <P>SOLUTION: A silencer 1 includes a cylindrical casing 2 provided with a flat section in a center-axis direction Z, an inlet pipe (a first pipe ) 6 provided so as to nearly align with a long diameter X of the flat section, and an outlet pipe (a second pipe) 7 provided parallel with the center-axis direction Z. The inlet pipe 6 and the outlet pipe 7 are arranged so as to intersect each other, and a vicinity of intersecting portion 6a of the inlet pipe 6 is formed in a flat section. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a silencer provided in an exhaust system of a vehicle or the like equipped with an internal combustion engine.

Conventionally, a silencer is provided in an exhaust system of a vehicle or the like equipped with an internal combustion engine for the purpose of reducing exhaust noise. A silencer, for example, contains a silencing element such as a partition plate or an inner pipe in a casing in which end plates are joined to both open ends of a cylindrical body formed of two or more outer cylinders to suppress radiated sound. Is formed. Such a silencer is disposed under the floor of the vehicle. However, due to space limitations, the center axis direction of the silencer casing may be disposed in the vehicle width direction. In such a case, there are many cases in which a first pipe in the radial direction of the cross section and a second pipe in the central axis direction are provided in the casing, and an upstream exhaust pipe and a downstream exhaust pipe are connected to each pipe. there were.
(See Patent Document 1)
JP-A-9-303133

  Recently, in order to secure the ground clearance of the vehicle while increasing the space in the vehicle interior, a silencer having a flatter section tends to be employed. On the other hand, a pipe provided in the silencer and through which exhaust gas flows is required to have a diameter larger than a certain diameter from the viewpoint of back pressure performance.

  Therefore, like the conventional silencer described above, the first pipe must be provided at the end of the silencer so as not to intersect the second pipe. For this reason, in order to connect the upstream side exhaust pipe to the first pipe, it is necessary to handle an extra exhaust pipe, which may cause problems in terms of space and cost. In addition, since it is necessary to arrange the first pipe and the second pipe so as not to intersect with each other, the design freedom of the silencer is low, and there is a problem in terms of the silencing performance.

  In order to solve the above-mentioned problem, the invention according to claim 1 includes a cylindrical casing having a flat cross section in the central axis direction, a first pipe provided so as to substantially coincide with the long diameter of the flat cross section, In a silencer including a second pipe provided in a central axis direction, the first pipe and the second pipe are arranged so as to intersect with each other, and at least − of the first pipe and the second pipe The silencer is characterized in that the vicinity of the crossing portion is formed in a flat cross section.

  According to a second aspect of the present invention, in the first aspect of the present invention, the vicinity of one of the first pipe and the second pipe is formed in a flat cross section, and the downstream side is the side formed in the flat cross section. It is a silencer characterized by connecting an exhaust pipe.

  A third aspect of the present invention is the silencer according to the first aspect, wherein a small hole is provided except in the vicinity of the intersection of the first pipe and the second pipe.

  According to the first aspect of the present invention, the silencer can have a more flat cross section without increasing the back pressure, and the ground clearance of the vehicle can be set high. At that time, since the first pipe can be set at an arbitrary position in the axial direction of the silencer, an effect can be exhibited in terms of space and cost. Moreover, the design freedom of the silencer can be increased, and the effect can be exhibited in terms of the silencing performance.

  According to the second aspect of the invention, an increase in back pressure can be suppressed and abnormal noise can be suppressed.

  If a small hole is provided near the intersection, the noise reduction effect may be reduced due to the short distance between the first pipe and the second pipe, or the flow rate of exhaust gas may increase due to flattening and noise may occur. It was. According to the third aspect of the present invention, such a silencing effect can be reduced and abnormal noise can be suppressed.

  The best mode for carrying out the present invention will be described based on the embodiment shown in FIGS.

  FIG. 1 shows a silencer 1 according to the first embodiment. (A) Plan sectional view, (b) is a sectional view taken along line AA in (a), and (c) is a sectional view taken along line BB in (a). It is sectional drawing.

  The casing 2 of the silencer 1 is formed by joining end plates 4 and 5 to a cylindrical body 3 in which a metal plate is formed in a two-layered cylinder so as to close both open ends 3b and 3c. . The cylindrical body 3 is formed in a flat elliptical cross section having a major axis X and a minor axis Y. The inside of the casing 2 is partitioned into two sound deadening chambers 13 and 14 by a partition plate 8 having a plurality of through holes 8a.

  The inlet pipe 6 for connecting to the upstream side exhaust pipe J as the first pipe is inserted through the opening 3 a formed in the cylindrical body 3 so as to substantially coincide with the major axis X of the elliptical cross section of the casing 2. It is provided so as to cross the body 3. The opening end 6 b in the casing 2 of the inlet pipe 6 is closed by a cap 9, and a plurality of small holes 11 that can communicate with the sound deadening chamber 14 are provided on the side surface of the inlet pipe 6. The cap 9 is fixed to a position facing the opening 3 a of the cylindrical body 3. In addition, the reinforcement member 10 is provided in the outer periphery of the opening part 3a of the cylindrical body 3, and the improvement of durability is achieved.

  An outlet pipe 7 for connecting to the downstream side exhaust pipe K as a second pipe is provided through the opening 4 a formed in the end plate 4 substantially parallel to the central axis direction Z of the casing 2. The outlet pipe 7 is provided so as to pass through the partition plate 8 and open to the silencing chamber 13, and a plurality of small holes 12 that can communicate with the silencing chamber 14 are provided on the side surface of the outlet pipe 7.

  As described above, the inlet pipe 6 and the outlet pipe 7 are provided so as to intersect with each other, and the vicinity 7a of the outlet pipe 7 is formed in a flat cross section so as not to contact the inlet pipe 6. Further, the small holes 11 and 12 provided in both the inlet pipe 6 and the outlet pipe 7 are provided except for the vicinity of the intersections 6a and 7a.

  The exhaust gas flowing through the upstream side exhaust pipe J flows into the muffler chamber 14 from the small hole 11 provided in the inlet pipe 6. The exhaust gas flows into the sound deadening chamber 13 through a through hole 8 a provided in the partition plate 8, passes through the outlet pipe 7 from the opening end 7 b of the outlet pipe 7, and is then guided to the downstream exhaust pipe K. A part of the exhaust gas is led directly from the sound deadening chamber 14 through the small hole 12 to the outlet pipe 7.

  Since the inlet pipe 6 substantially coincides with the major axis direction X of the elliptical cross section of the casing 2 as described above and is provided so as to cross the cylindrical body 3, the silencer can be supported in a well-balanced manner. is there. For this reason, the vibration of the silencer can be reduced, and the effect of improving the durability and reducing the humming noise transmitted to the vehicle interior is exhibited. Moreover, in the present Example 1, since the cross-section vicinity 7a of the outlet pipe 7 to which the downstream exhaust pipe K is connected is formed in a flat cross section, an increase in back pressure and generation of abnormal noise can be suppressed.

  Since the diameter of the inlet pipe 6 and the outlet pipe 7 can be secured to a certain diameter or more and the silencer can be made to have a flatter cross section while suppressing the increase in back pressure, the ground clearance of the vehicle can be increased. At that time, since the inlet pipe 6 can be set at an arbitrary position in the axial direction of the silencer, an effect can be exhibited in terms of space and cost. Moreover, the design freedom of the silencer can be increased, and the effect can be exhibited in terms of the silencing performance. Further, since the small holes 11 and 12 are provided except for the vicinity of the intersections 6a and 7a of the inlet pipe 6 and the outlet pipe 7, the generation of abnormal noise can be suppressed.

  2A and 2B show a silencer 21 of Example 2. FIG. 2A is a sectional view taken along a plane, FIG. 2B is a sectional view taken along the line CC in FIG. 2A, and FIG. 2C is a sectional view taken along the line DD in FIG. FIG.

  In the second embodiment, the inlet pipe 26 as the first pipe and the outlet pipe 27 as the second pipe are provided so as to intersect with each other, and the vicinity 26a, 27a of the inlet pipe 26 and the outlet pipe 27 do not contact each other. Thus, it is formed in a flat cross section. Since other configurations are the same as those in the first embodiment, the same reference numerals are given and description thereof is omitted.

  In the second embodiment, the same effects as those of the first embodiment are exhibited. Furthermore, since it is possible to reduce the flatness of the inlet pipe 26 and the outlet pipe 27, it is possible to further suppress an increase in back pressure and generation of abnormal noise.

  3A and 3B show a silencer 31 according to the third embodiment. FIG. 3A is a plan sectional view, FIG. 3B is a sectional view taken along line EE in FIG. 3A, and FIG. 3C is a sectional view taken along line FF in FIG. It is sectional drawing.

  In the third embodiment, the inlet pipe 36 as the first pipe and the outlet pipe 37 as the second pipe are provided so as to intersect with each other, and the vicinity 36a of the inlet pipe 36 is flat so as not to contact the outlet pipe 37. It is formed in a cross section. Since other configurations are the same as those in the first embodiment, the same reference numerals are given and description thereof is omitted.

  In the first to third embodiments, the first pipe is an inlet pipe and the second pipe is an outlet pipe. However, the first pipe may be an outlet pipe and the second pipe may be an inlet pipe. In addition, a cylindrical casing having an arbitrary flat cross section can be employed.

BRIEF DESCRIPTION OF THE DRAWINGS It shows the silencer of Example 1 of this invention, (a) is the plane sectional view, (b) is the sectional view on the AA line in (a), (c) is the sectional view on the BB line in (a). Figure. The silencer of Example 2 of this invention is shown, (a) is the plane sectional drawing, (b) is the CC sectional view taken on the line in (a), (c) is the DD sectional view in (a). Figure. 1 shows a silencer according to a first embodiment of the present invention, in which (a) is a plan sectional view thereof, (b) is a sectional view taken along line EE in (a), and (c) is a sectional view taken along line FF in (a). Figure.

Explanation of symbols

1, 21, 31 Silencer 2 Casing 6, 26, 36 Inlet pipe (first pipe)
7, 27, 37 Outlet pipe (second pipe)
6a, 7a, 26a, 27a, 36a, 37a Intersection X Long diameter Y Short diameter Z Central axis

Claims (3)

In a silencer comprising a cylindrical casing having a flat cross section in the central axis direction, a first pipe provided so as to substantially coincide with the long diameter of the flat cross section, and a second pipe provided in the central axis direction The silencer is disposed so that the first pipe and the second pipe intersect with each other, and at least one of the intersections of the first pipe and the second pipe is formed in a flat cross section. . 2. The muffler according to claim 1, wherein the intersection of one of the first pipe and the second pipe is formed in a flat cross section, and a downstream exhaust pipe is connected to the side formed in the flat cross section. vessel. The silencer according to claim 1, wherein a small hole is provided except in the vicinity of an intersection of the first pipe and the second pipe.

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