JP2007224778A - Muffler structure for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a muffle structure for a vehicle capable of restraining a radiation sound generated in a muffling part. <P>SOLUTION: A muffler 10 is formed by applying the muffler structure for the vehicle, and has an upper muffler 12 formed as a hollow structure, an inlet pipe 16 formed in a cylindrical shape and having one end opening in the upper muffler 12 by penetrating through the upper muffler 12, and a separator 74 integrally formed in the inlet pipe 16, positioned inside the upper muffler 12 and connecting the upper wall 12A of the upper muffler 12, a lower wall 12B and the inlet pipe 16. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle muffler structure attached to a vehicle such as an automobile.

As a muffler applied to an automobile exhaust system, a flat muffler in which the size in the vertical direction of the vehicle body is smaller than the size in the vehicle width direction is known (for example, see Patent Document 1).
Japanese Patent Laid-Open No. 6-328954

  However, the flat muffler according to the prior art as described above has relatively low rigidity of the upper and lower flat surfaces along the longitudinal direction of the flat cross section, and therefore, when an inlet pipe for introducing exhaust gas is inserted into the muffler. There is a concern that the radiated sound will increase.

  In view of the above fact, an object of the present invention is to obtain a vehicle muffler structure capable of suppressing radiated sound generated in a silencer.

  In order to achieve the above-mentioned object, a muffler structure for a vehicle according to the first aspect of the present invention is a muffler part formed as a hollow structure, and is formed in a cylindrical shape, and has one end penetrating through an outline of the muffler part. An exhaust circulation cylinder that is open in the silencer, and an exhaust circulation cylinder that is integrally formed with the exhaust circulation cylinder and is located inside the silencer, and connects the outer wall of the silencer and the exhaust circulation cylinder Reinforcing means.

  In the muffler structure for a vehicle according to claim 1, the exhaust circulation cylinder that penetrates the outer wall of the silencer and opens one end in the silencer constitutes an exhaust introduction part or an exhaust part. The exhaust gas introduced into (inside) is silenced and discharged by, for example, expansion or resonance in the silencer. Here, in the muffler structure for the vehicle, the reinforcing means connects the exhaust circulation cylinder, which is a high-rigidity member formed in a cylindrical shape (closed cross-section structure), and the outer shape of the silencer in the silencer, Since the outer shell of the silencer is reinforced, the rigidity of the silencer outer shell in the connecting direction by the reinforcing means is improved. Thereby, the radiated sound radiated from the outer surface of the silencer can be suppressed.

  Thus, in the vehicle muffler structure according to the first aspect, it is possible to suppress the radiated sound generated in the flat-shaped silencer. The reinforcing means may be formed integrally with the exhaust circulation cylinder, or may be formed separately from the exhaust circulation cylinder and fixed integrally with the exhaust circulation cylinder. good.

  A vehicle muffler structure according to a second aspect of the invention is the vehicle muffler structure according to the first aspect, wherein the silencer has a flat outer portion formed in a flat shape, and the exhaust circulation cylinder The body penetrates a portion between the flat outlines in the flat outline and is joined to the flat outline at the penetration site, and the reinforcing means connects the flat planes of the flat outline.

  In the muffler structure for a vehicle according to claim 2, the rigidity in the flat direction of the flat shell portion is obtained by connecting the flat surfaces that are likely to be low rigidity portions in the silencer by the reinforcing means reinforced by the exhaust circulation cylinder. improves. That is, it is possible to suppress the vibration of each flat surface in the flat direction, and to effectively suppress the radiated sound radiated from the flat surface.

  The vehicle muffler structure according to a third aspect of the present invention is the vehicle muffler structure according to the second aspect, wherein the reinforcing means includes an inner space of the flat outer portion and a closed space surrounding the exhaust circulation cylinder. It constitutes at least a part of the partition wall partitioned into other spaces.

  In the vehicle muffler structure according to claim 3, since the inside of the flat outer portion is partitioned into at least two spaces (partition chambers) including a closed space surrounding the exhaust circulation cylinder and other spaces, the closed space The rigidity of the reinforcement part by the reinforcement means which comprises at least one part of this partition is higher. In particular, in the configuration in which the exhaust gas distribution cylinder is applied to the exhaust gas introduction portion, the exhaust gas has a large energy, so that the rigidity of the silencer outer shell is improved on the introduction side, so that the radiation noise suppression effect is increased. .

  A vehicle muffler structure according to a fourth aspect of the present invention is the vehicle muffler structure according to the second or third aspect, wherein the muffler portion is located on the outer side in the flat direction of the flat outer portion and in the flat outer portion. It further has a protruding outer portion connected to one flat surface.

  In the muffler structure for a vehicle according to the fourth aspect, the protruding outer portion protrudes from the flat surface side on one side of the flat outer portion. Thereby, the silencer has a rigidity of the flat surface on the connecting side of the protruding outer portion in the flat outer portion higher than the rigidity of the other flat surface, and the flat surface on the high rigidity side and the other flat surface are Since it is connected, the radiation sound suppressing effect of the other flat surface is high.

  A vehicle muffler structure according to a fifth aspect of the present invention is the vehicle muffler structure according to any one of the first to fourth aspects, wherein the reinforcing means is entirely disposed from an opening end of the exhaust circulation cylinder. It is a plate-like body extending toward the outer shell of the muffling portion over the circumference, and the boundary portion with the opening end of the exhaust circulation cylinder has a round shape that widens the opening area of the opening end. .

  In the muffler structure for a vehicle according to claim 5, since the boundary between the opening end of the exhaust circulation cylinder and the plate-like (flat plate-like) reinforcing means is rounded around the entire circumference, in other words, the exhaust Since the stress concentration at the boundary between the distribution cylinder and the reinforcing means is alleviated, the effect of reinforcing the silencer shell by the reinforcing means is improved. Further, since the reinforcing means is continuous from the opening end of the exhaust circulation cylinder, it is easy to form them integrally.

  As described above, the muffler structure for a vehicle according to the present invention has an excellent effect that it is possible to suppress the radiated sound generated in the silencer.

  A muffler 10 to which a vehicle muffler structure according to a first embodiment of the present invention is applied will be described with reference to FIGS. 1 to 6. For convenience of explanation, the directions indicated by the arrows FR, UP, and W as appropriate in the drawings are the forward direction (traveling direction), the upward direction, and the vehicle width direction of the vehicle on which the muffler 10 is mounted. .

  FIG. 4 is a perspective view of the muffler 10 to which the vehicle muffler structure according to the embodiment of the present invention is applied. As shown in this figure, the muffler 10 is composed of an upper muffler (upper shell) 12 as a flat outer portion constituting the muffling portion in the present invention, and a protruding outer shape connected to the lower side of the upper muffler 12 and constituting the muffling portion. A lower muffler (lower shell) 14 as a part and an inlet pipe 16 as an exhaust circulation cylinder (gas introduction part) for introducing exhaust gas into the upper muffler 12 are configured.

  The upper muffler 12 is a hollow structure that is formed in a substantially rectangular shape that is long in the vehicle width direction in a plan view and that is formed in a flat shape that has a smaller vertical dimension than a front-rear dimension in a side view. Therefore, in the upper muffler 12, the vertical direction of the vehicle body is the flat direction, and the longitudinal direction of the vehicle body and the vehicle width direction are grasped as the longitudinal direction of the flat cross section. In this embodiment, the vehicle body longitudinal direction is mainly described as the longitudinal direction of the flat cross section in the present invention. Further, the upper muffler 12 is a flat plane in which the upper wall 12A and the lower wall 12B extend along a substantially horizontal plane.

  As shown in FIG. 2 with the upper wall 12A partially cut away, the interior of the upper muffler 12 is surrounded by three pairs of partition plates 18, 20, 22 arranged substantially symmetrically with respect to the center in the vehicle width direction. It is divided into seven in the width direction. A space sandwiched between the partition plates 18 in the upper muffler 12 is defined as a first chamber 24, and spaces adjacent to the outer sides of the first chamber 24 in the vehicle width direction are sandwiched between the partition plates 18 and the partition plates 20. Spaces adjacent to the outer side in the vehicle width direction of the second chamber 26 between the partition plates 20 and the partition plates 22 are respectively defined as third chambers 28, and the partition plate 22, that is, the vehicle in the first chamber 24. The spaces adjacent to the outside in the width direction are respectively fourth chambers 30.

  The first chamber 24 in the upper muffler 12 is partitioned forward and backward by a separator portion 74 described later. Specifically, the separator 74 converts the first chamber 24 into an exhaust gas introduction chamber 24A into which exhaust gas is introduced from the inlet pipe 16, and a communication chamber 24B as a closed space located in front of the exhaust gas introduction chamber 24A. It is partitioned. Each partition plate 18 is formed with a plurality of through holes (not shown) that allow the exhaust gas to flow from the exhaust gas introduction chamber 24 </ b> A of the first chamber 24 to the second chamber 26. Further, each partition plate 18 is formed with a plurality of through holes (not shown) that communicate the communication chambers 24 </ b> B and the second chambers 26. Therefore, the two second chambers 26 communicate with each other via the communication chamber 24B.

  In the upper muffler 12, two partition plates 18 that pass through the partition plates 18 and different partition plates 20 and communicate with the second chamber 26 on one side in the vehicle width direction and the third chamber 28 on the other side are communicated. A communication pipe 32 is provided. Further, as shown in FIGS. 1 to 3, the upper muffler 12 passes through the partition plate 18 and the partition plate 20 on one side with respect to the center in the vehicle width direction, and one end opens into the third chamber 28. A pair of communication pipes 34 having the other end penetrating the lower wall 12B and opening into the lower muffler 14 are disposed. As shown in FIG. 3, each communication pipe 34 is curved so as to form a substantially right angle in the rear view in the exhaust gas introduction chamber 24A.

  Further, a pair of outlet pipes 36 arranged in parallel in the vehicle width direction are connected to the lower wall 12B of the upper muffler 12, respectively. As shown in FIGS. 1 and 4, the pair of outlet pipes 36 penetrates the rear wall 44 of the lower muffler 14 and opens to the outside. Therefore, each of the pair of outlet pipes 36 communicates the rear portion of the exhaust gas introduction chamber 24A of the upper muffler 12 and the external space.

  As shown by a broken line in FIG. 2, the lower muffler 14 is formed in a substantially rectangular shape having a size in the front-rear direction equal to that of the upper muffler 12 in plan view and a size in the vehicle width direction smaller than that of the upper muffler 12. In this embodiment, the dimension in the vehicle width direction substantially coincides with the interval between the partition plates 18. Further, as shown in FIGS. 1 to 4, the bottomed cylindrical shape is such that the peripheral wall 14 </ b> B is erected from the periphery of the substantially rectangular bottom portion 14 </ b> A in the plan view.

  In the lower muffler 14, the upper opening end of the peripheral wall 14 </ b> B is connected (linked) to the center in the vehicle width direction of the lower wall 12 </ b> B of the upper muffler 12. In this embodiment, as shown in FIGS. 1 and 3, the upper end of the peripheral wall 14B is continuously or intermittently welded or the like to a band-shaped connecting bracket 38 that is fixed to the lower wall 12B and has an annular shape in plan view. It is fixed. Therefore, the lower muffler 14 is closed by the upper muffler 12 to form a hollow structure.

  The peripheral wall 14 </ b> B of the lower muffler 14 extends in the vertical direction that matches the flat direction of the upper muffler 12. A pair of side walls 40 extending along the front direction of the vehicle body and the vertical direction of the vehicle body on the peripheral wall 14B are connected below the corresponding partition plate 18 so as to intersect the partition plate 18 a plurality of times. (See FIG. 2). Further, a front wall 42 and a rear wall 44 that extend along substantially the vehicle width direction and substantially the vehicle body vertical direction and connect the front and rear ends of the pair of side walls 40 are respectively located below the front and rear ends of the upper muffler 12. Yes. That is, the pair of side walls 40 of the lower muffler 14 are connected to the lower wall 12B including the middle portion in the front-rear direction so as to connect both front and rear ends (high rigidity portions) of the lower wall 12B of the upper muffler 12. Yes.

  As described above, the portion of the lower wall 12B of the upper muffler 12 that mainly constitutes the first chamber 24 forms a closed cross section with the lower muffler 14 when viewed from any of the planar view, the layout view, and the side view. The lower muffler 14 is reinforced (stiffened).

  Further, as shown in FIG. 1, a partition plate 46 that partitions the space in the lower muffler 14 forward and backward is disposed in the lower muffler 14, and the space on the front side of the partition plate 46 is the above-described communication pipe 34. Is a fifth chamber 48 opened. On the other hand, the space on the rear side of the partition plate 46 is a sixth chamber 50, and the outlet pipe 36 described above passes through the lower chamber 12 </ b> B and the rear wall 44 through the sixth chamber 50, thereby exhaust gas introduction chamber. It opens to 24A and the outside.

  Further, as shown in FIG. 1, an outlet pipe 52 having a front end opened in the lower muffler 14 and penetrated through the partition plate 46 and the rear wall 44 and a rear end opened to the outside is disposed in the lower muffler 14. It is installed. Therefore, the exhaust gas introduced into the fifth chamber 48 via the communication pipe 34 is discharged to the outside through the outlet pipe 52.

  As shown in FIGS. 1, 2, and 4, the inlet pipe 16 penetrates through the front wall 12 </ b> C positioned between the upper wall 12 </ b> A and the lower wall 12 </ b> B that are upper and lower flat surfaces in the upper muffler 12. A part of which enters the first chamber 24. As shown in FIGS. 2 and 6, in this embodiment, the inlet pipe 16 is arranged slightly offset with respect to the center in the width direction of the upper muffler 12, but may be arranged at the center. The inlet pipe 16 is fixed to the upper muffler 12 by welding or the like at a through portion (edge portion of the through hole) 12D with the front wall 12C of the upper muffler 12. The inlet pipe 16 includes a merging pipe portion 54 located outside the upper muffler 12 and a discharge pipe portion 56 located inside the upper muffler 12 as main components.

  As shown in FIGS. 1 and 3, the merging pipe portion 54 includes connection portions 54 </ b> A and 54 </ b> B to which a pair of exhaust pipes (not shown) communicating with the exhaust manifold of the internal combustion engine are connected independently. And a merging portion 54C for merging the exhaust gases introduced from 54A and 54B, respectively. The connecting portions 54A and 54B are inclined so that the front end side is lower than the rear end side. The confluence portion 54C is arranged along the horizontal plane and is continuous with the rear ends of the connection portions 54A and 54B, and is vertically higher than the vehicle width direction dimension of the cross section substantially orthogonal to the horizontal direction (macro flow direction). It is formed in a flat shape with small dimensions.

  The discharge pipe portion 56 is continuously disposed behind the merging portion 54C along the horizontal plane, and has a flat cross-sectional shape like the merging portion 54C. As shown in FIGS. 1 and 4, a gas exhaust port 58 that is an open end for blowing exhaust gas into the exhaust gas introduction chamber 24 </ b> A of the first chamber 24 is provided at the rear end of the exhaust pipe portion 56. .

  The discharge pipe portion 54 described above is formed in a tubular shape having the above-described shape by joining the upper half 64 as the first half and the lower half 66 as the second half. The upper half 64 is a half pipe shape in which the upper halves of the merging pipe part 54 (connection parts 54A, 54B, 54C) and the discharge pipe part 56 are integrally formed and open downward (front part forming the connection parts 54A, 54B). Is formed in a shape of two half pipes), and a joining flange 68 projects from the portion constituting the merging pipe portion 54 along the vehicle width direction. The lower half 66 is formed in a half pipe shape in which the lower halves of the merging pipe portion 54 and the discharge pipe portion 56 are integrally formed and open upward, and a joining flange 70 is formed from a portion constituting the merging pipe portion 54. Projects along the vehicle width direction.

  The discharge pipe portion 56 is formed in a tubular shape by abutting the lower opening end of the upper half 64 and the upper opening end of the lower half 66 and joining the upper and lower joining flanges 68 and 70 by welding or the like. Yes. A ring member 72 for joining to the exhaust pipe is fixed to the front ends of the connecting portions 54A and 54B in a fitted state, and the front ends are strengthened. Note that the joining flanges 68 and 70 are not set in the exhaust pipe portion 56 that is located in the upper muffler 12 and is allowed to leak exhaust gas.

  As shown in FIG. 1, the inlet pipe 16 described above is integrally formed with a separator 74 as a reinforcing (stiffening) means for partitioning the first chamber 24 into an exhaust gas introduction chamber 24A and a communication chamber 24B. . As shown in FIG. 5, a substantially rectangular flat plate-like separator body 74A extending in the vertical direction and the vehicle width direction from the outer peripheral portion of the discharge pipe portion 56, and an upper wall extending forward from the upper edge of the separator body 74A. 12A, an upper flange 74B fixed to the inner surface of the separator body 74A, a lower flange 74C extending forward from the lower edge of the separator body 74A and fixed to the inner surface of the lower wall 12B, and a front side from both edges of the separator body 74A in the vehicle width direction. The side flanges 74 </ b> D that extend to the partition plate 18 and are fixed to the partition plate 18 are the main components.

  In this embodiment, the substantially rectangular flat plate-shaped separator main body 74A extends from the edge (opening edge) of the gas discharge port 58 in the discharge pipe portion 56, and as shown in FIG. 74C and 74D are continuously ring-shaped as a whole. The upper muffler 12 and the partition plate 18 are fixed to each flange 74B, 74C, 74D by welding or the like.

  As described above, in the muffler 10, the gas discharge port 58 of the discharge pipe portion 56 opens in the first chamber 24 only in the exhaust gas introduction chamber 24 </ b> A. In addition, the separator 74 includes a communication chamber 24 </ b> B that is a closed space surrounding the discharge pipe portion 56 with the upper wall 12 </ b> A, the lower wall 12 </ b> B, the front wall 12 </ b> C, and the left and right partition plates 18 (the front portions). It is composed. The upper wall 12A and the lower wall 12B of the upper muffler 12 are connected via a separator 74 to a discharge pipe portion 56 (inlet pipe 16) that is a highly rigid member having a cylindrical shape (having a closed sectional structure). Yes. In other words, the upper wall 12 </ b> A and the lower wall 12 </ b> B are connected to each other via the separator 74 and the discharge pipe portion 56.

  The structure of the separator 74 whose function has been mainly described above will be supplemented. As shown in FIG. 5, the separator 74 includes an upper separator 76 formed integrally with the upper half 64 and a lower separator 78 formed integrally with the lower half 66. The upper separator 76 is formed with the upper portion of the separator 74 (the upper portions of the separator main body 74A and the side flange 74D and the upper flange 74B), and the lower separator 78 is formed with the lower portion of the separator 74 (the separator main body 74A and the side flange 74D). The lower and lower flanges 74C) are formed.

  As shown in FIG. 1, the discharge pipe portion 56 of the inlet pipe 16 is disposed slightly offset from the center in the vertical direction of the communication chamber 24 </ b> B, and the upper separator 76 has a larger vertical dimension than the lower separator 78. It is configured. In this embodiment, the upper separator 76 and the lower separator 78 are not fixed, but they may be fixed by welding or the like.

  The upper half 64 integrally formed with the upper separator 76 and the lower half 66 integrally formed with the lower separator 78 are formed by, for example, press working, forging, casting or the like using stainless steel or titanium alloy as a material. The

  3 and 4, the muffler 10 described above is connected to the lower side in the vehicle vertical direction with respect to the upper muffler 12 elongated in the vehicle width direction and the lower wall 12B of the upper muffler 12. The muffler 14 is formed in a substantially T shape in rear view. As a result, the automobile equipped with the muffler 10 is configured to ensure the required muffler capacity while ensuring a wide space R on the both sides with respect to the center in the vehicle width direction (lower muffler 14). The present invention is applied to an application for reducing exhaust gas noise of a relatively large internal combustion engine.

  Further, the muffler 10 is connected to a valve device (not shown) for opening and closing the pair of outlet pipes 36 so as to switch the exhaust system path. Specifically, with respect to the short path for exhausting air through the inlet pipe 16, the first chamber 24, and the pair of outlet pipes 36, the exhaust gas introduction chamber 24 </ b> A of the upper muffler 12, the second chamber 26, and the second chamber 26. The configuration is such that the third chamber 28 (communication pipe 32) on the opposite side in the width direction, the fifth chamber 48 of the lower muffler 14 and the long path exhausted via the outlet pipe 52 can be switched. Note that the communication chamber 24B that communicates with the left and right second chambers 26 can be used as a tuning element for tuning exhaust sound, for example, as a resonance chamber or an expansion chamber.

  Next, the operation of the first embodiment will be described.

  In the muffler 10 having the above configuration, for example, when the engine speed is lower than a predetermined threshold, the exhaust gas introduced from the inlet pipe 16 mainly includes the exhaust gas introduction chamber 24A, the second chamber 26, and the second chamber 26 of the upper muffler 12. The sound is silenced via the third chamber 28 (communication pipe 32) opposite to the second chamber 26 in the width direction, the fifth chamber 48 of the lower muffler 14, and the outlet pipe 52, and exhausted to the outside. On the other hand, when the engine speed exceeds the threshold value, the exhaust gas introduced from the inlet pipe 16 is silenced via the exhaust gas introduction chamber 24A of the upper muffler 12 and the pair of outlet pipes 36 and is exhausted to the outside. . In this case, the exhaust gas is discharged through a short path, so that the exhaust resistance is small and the engine output is improved.

  Here, in the muffler 10 having the upper muffler 12 formed in a flat shape, the upper wall 12A and the lower wall 12B constituting the flat surface of the upper muffler 12 are connected to the discharge pipe portion 56 via the separator 74. Therefore, the upper wall 12A and the lower wall 12B are reinforced in the vertical direction. Therefore, the upper wall 12A and the lower wall 12B of the upper muffler 12 have high vertical rigidity and suppress vibration in the vertical direction, so that the radiated sound emitted from the flat upper muffler 12 is suppressed. be able to.

  This effect will be described in comparison with a comparative example shown in FIG. The muffler 100 according to the comparative example is a wound muffler that is flattened in the vertical direction, and an inlet pipe 104 is introduced from the front wall 102. The inlet pipe 104 introduces exhaust gas into the rear end opening 104 </ b> A and exhaust holes 104 </ b> B provided in the pipe wall. The muffler 100 has a small difference in rigidity between the upper surface 100A and the lower surface 100B, and also a small difference in rigidity between the upper surface 100A and the lower surface 100B. Therefore, no matter where the exhaust gas hits the upper surface 100A or the lower surface 100B, radiated sound is emitted. Prone to occur. Therefore, it is difficult to reduce the radiated sound only by devising the discharge direction of the inlet pipe 104, and in order to reduce the radiated sound, for example, measures such as sandwiching a sound insulating material such as glass wool with the outer wall of the muffler 100 as a multilayer structure. Was necessary.

  On the other hand, in the muffler 10, the separator 74 provided in the inlet pipe 16 reinforces the upper wall 12A and the lower wall 12B as described above, that is, the discharge pipe portion 56 which is a highly rigid structure having a closed cross-sectional shape. Since the separator 74 strengthened by the reinforcement reinforces the upper wall 12A and the lower wall 12B, it has been realized that the muffler 10 as a whole can reduce the radiation noise. Moreover, in the muffler 10, the separator 74 forms a part of the outer wall (outer wall having a double closed cross-sectional structure including the discharge pipe part 56) surrounding the communication chamber 24 </ b> B that is a closed space around the discharge pipe part 56. The rigidity of the reinforcement part by the separator 74 in the muffler 12 is further improved. For this reason, the radiated sound radiated | emitted from the upper muffler 12 made into the flat shape can be suppressed.

  As described above, in the muffler 10 to which the vehicle muffler structure according to the first embodiment is applied, it is possible to suppress the radiated sound generated in the flat upper muffler 12.

  Furthermore, in the muffler 10, the pair of side walls 40 of the lower muffler 14 is connected to the lower wall 12 </ b> B of the upper muffler 12 that is likely to cause radiated sound. In other words, the lower wall 12 </ b> B is reinforced by the lower muffler 14. Therefore, the rigidity of the lower wall 12B is higher than the rigidity of the upper wall 12A. Since the lower wall 12B and the upper wall 12A having high rigidity are connected by the separator 74, the reinforcing (stiffening) effect of the upper wall 12A having relatively low rigidity is improved. Thereby, the muffler 10 as a whole can further reduce the radiated sound.

  And since the separator 74 is integrally extended from the edge part of the gas exhaust port 58 in the exhaust pipe part 56 of the inlet pipe 16 which is an exhaust gas introduction part, the energy which exhaust gas has greatly produces a radiated sound. Easy parts are effectively reinforced. Therefore, the muffler 10 has a greater exhaust noise reduction effect than a configuration in which the flat plate-like separator 74 extending in the vertical direction is provided in other portions. Further, by extending the separator 74 from the open end, that is, the rear end of the discharge pipe portion 56, the communication chamber 24B can be set wide, and tuning for improving the muffler performance as a muffler (expansion device or resonator) is performed. The width expands.

  Further, in the muffler 10, the separator 74, the upper wall 12A, the lower wall 12B, the front wall 12C, and the left and right partition plates 18 of the upper muffler 12 constitute an outer wall that surrounds the communication chamber 24B. The outer portion surrounding 24B has higher rigidity than the other portions. For this reason, in the muffler 10, the resonance frequency differs greatly between the outer portion surrounding the communication chamber 24B and other portions (vibration coupling is suppressed), and the resonance frequency of the outer portion is in a band where there is no practical problem. Therefore, the resonance characteristics of the upper muffler 12 other than the outer portion surrounding the communication chamber 24B may be considered. And since the part other than the outer part surrounding the communication chamber 24B in the upper muffler 12 constitutes a vibration system having a shorter front-rear length than the upper muffler 12 when the separator 74 is not provided, the resonance frequency becomes higher. Thereby, a radiated sound can be suppressed more effectively.

  Furthermore, in the muffler 10, since the discharge pipe portion 56 of the inlet pipe 16 is disposed along the longitudinal direction of the vehicle body, which is the longitudinal direction of the flat cross section, the gas flow introduced into the upper muffler 12 becomes the longitudinal direction of the vehicle body. (Exhaust velocity component is large), and the exhaust gas discharged from the inlet pipe 16 is less likely to face the upper wall 12A side. Since this structure prevents exhaust gas from directly hitting the upper wall 12A, it contributes to suppressing radiated sound.

  In the muffler 10, since the separator 74 is integrally formed with the discharge pipe portion 56 of the inlet pipe 16, more specifically, the upper separator 76 is integrally formed with the upper half 64 constituting the inlet pipe 16. In addition, since the lower separator 78 is integrally formed with the lower half 66, the separator 74 is configured by joining the joining flanges 68 and 70. Thus, in the muffler 10, work such as welding for joining the separator 74 to the discharge pipe portion 56 can be made unnecessary. Furthermore, the yield of the material which comprises these can be improved, and the number of parts can be reduced.

  Next, a second embodiment of the present invention will be described with reference to FIGS. Note that parts and portions that are basically the same as those in the first embodiment of the gradator are denoted by the same reference numerals as those in the first embodiment, and description thereof is omitted. Moreover, illustration may be omitted.

  7 shows a muffler 80 to which a vehicle muffler structure according to a second embodiment of the present invention is applied, in a side sectional view corresponding to FIG. 1, and FIG. Is shown in a perspective view corresponding to FIG. As shown in these drawings, in the muffler 80, the boundary between the gas discharge port 58, which is the opening end of the discharge pipe portion 56, and the separator 74 widens the opening width and height of the gas discharge port 58 backward. It is different from the first embodiment in that it is a round shape portion 82.

  The round shape portion 82 is continuously formed over the entire circumference of the gas discharge port 58. As a result, stress concentration at the boundary between the discharge pipe portion 56 and the separator 74 is unlikely to occur, and the posture change (relative displacement) of the separator 74 with respect to the discharge pipe portion 56 is suppressed (stiffness is improved). . Therefore, the separator 74 in the present embodiment is further enhanced in rigidity as compared with the first embodiment. Other configurations of the muffler 80 are the same as the corresponding configurations of the muffler 10.

  Therefore, the muffler 80 according to the second embodiment can obtain the same effect by the same operation as that according to 10 according to the first embodiment. Moreover, in the muffler 80, since the rigidity of the separator 74 itself is improved by providing the shape portion 82, the effect of reinforcing the upper wall 12A and the lower wall 12B by the separator 74 is high. Thereby, in the muffler 80, it becomes possible to suppress a radiated sound still more effectively.

  In addition, since there are many elements that improve the rigidity of the upper muffler 12, restrictions on the muffler design are reduced. That is, for example, instead of a part of the rigidity improving element in the first embodiment, a round shape portion 82 may be provided. Similarly, the muffler 10 may be configured not to include some of the above-described rigidity improving elements.

  In each of the above-described embodiments, the mufflers 10 and 80 are provided with the upper muffler 12 and the lower muffler 14. However, the present invention is not limited to this. For example, the muffler 10 or the like does not include the lower muffler 14. It is good also as a structure. That is, the present invention is not limited to the basic configuration of the muffler 10 having the above-described configuration, and can be implemented with various modifications such as being applicable to, for example, a cylindrical muffler that is not a flat structure.

  In each of the above embodiments, the separator 74 is integrally formed with the discharge pipe portion 56. However, the present invention is not limited to this, and for example, the separator 74 is integrated with the discharge pipe portion 56 by welding or the like. May be joined together. In this case, the separator 74 may not be configured to be continuous with the edge of the gas discharge port 58.

  Further, in each of the above embodiments, the example in which the inlet pipe 16 is divided into the upper half 64 and the lower half 66 has been described. However, the present invention is not limited to this. For example, the inlet pipe 16 is integrated (seamless). None) and may be divided into three or more parts. Needless to say, the cross-sectional shape of the flow path of the inlet pipe 16 is not limited to the above embodiment.

It is a figure which shows the muffler which concerns on the 1st Embodiment of this invention, Comprising: It is sectional drawing which follows the 1-1 line | wire of FIG. It is the top view which a part of muffler concerning a 1st embodiment of the present invention cut away. It is sectional drawing which follows the 3-3 line of FIG. 1 is a perspective view of a muffler according to a first embodiment of the present invention. It is a perspective view of an inlet pipe and a separator which constitute a muffler concerning a 1st embodiment of the present invention. It is a rear view of the separator which comprises the muffler which concerns on the 1st Embodiment of this invention. It is a figure which shows the muffler which concerns on the 2nd Embodiment of this invention, Comprising: It is sectional drawing which follows the 1-1 line | wire of FIG. It is a perspective view of the inlet pipe and separator which comprise the muffler which concerns on the 2nd Embodiment of this invention. It is a perspective view of the muffler which concerns on the comparative example with embodiment of this invention.

Explanation of symbols

10 Muffler (vehicle muffler structure)
12 Upper muffler (flat outline, silencer)
12A Upper wall (flat surface)
12C front wall (the part between the flat surfaces in the flat shell)
14 Lower muffler (protruding outline)
16 Inlet pipe (cylinder for exhaust circulation)
24B Communication room (closed space surrounding the exhaust circulation cylinder)
74 Separator (reinforcing means)
80 muffler (vehicle muffler structure)
82 R-shaped part (R-shaped)

Claims (5)

A muffler formed as a hollow structure;
An exhaust circulation cylinder that is formed in a cylindrical shape and penetrates the outer wall of the muffling part and has one end opened in the muffling part;
Reinforcing means that is integrally formed with the exhaust circulation cylinder and is located on the inner side of the silencer, and connects the outer wall of the silencer and the exhaust circulation cylinder;
Vehicle muffler structure with The muffler has a flat outer portion formed in a flat shape,
The exhaust circulation cylinder passes through a portion between flat surfaces in the flat outer portion and is joined to the flat outer portion at the penetrating portion,
The vehicle muffler structure according to claim 1, wherein the reinforcing means connects the flat surfaces of the flat outer portion.   The dual-use muffler structure according to claim 2, wherein the reinforcing means constitutes at least a part of a partition wall that divides the internal space of the flat outer shell portion into a closed space surrounding the exhaust circulation cylinder and another space. .   4. The vehicle muffler structure according to claim 2, wherein the muffler portion further includes a projecting outer shell portion that is located on the outer side in the flat direction of the flat outer shell portion and is connected to one flat surface of the flat outer shell portion.   The reinforcing means is a plate-like body that extends from the open end of the exhaust circulation cylinder toward the outer shell of the muffler over the entire circumference, and a boundary with the open end of the exhaust circulation cylinder The vehicle muffler structure according to any one of claims 1 to 4, wherein the portion has a round shape that widens the opening area of the opening end.

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