Exhaust muffler support structure

Abstract

To provide an exhaust muffler support structure capable of reducing vibrations in a vehicle.SOLUTION: An exhaust muffler support structure comprises: an engine; a catalyst converter and an exhaust muffler both suspended at a lower section of a vehicle; a first exhaust pipe connecting edge sections of the engine and the catalyst converter; a second exhaust pipe connecting the edge sections of the catalyst converter and the exhaust muffler; a first elastic body supporting one of the edge sections of the exhaust muffler; a second elastic body supporting the other of the edge sections of the exhaust muffler; and a third elastic body supporting one edge section or the other edge section of the catalyst converter. The third elastic body has lower rigidity than the first elastic body and the second elastic body.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a support structure for an exhaust muffler.

Background Art

[0002] Patent Document 1 discloses a configuration in which an engine and an exhaust muffler are arranged relative to each other in the direction of the output shaft of the engine, and a low-rigidity portion for suppressing the transmission of vibration from the engine to the exhaust muffler is provided in the middle of the exhaust pipe leading from the engine to the exhaust muffler. Further, Patent Document 1 discloses that both ends of the exhaust muffler are supported by the vehicle body via rubber mounts.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the configuration disclosed in Patent Document 1, the exhaust muffler and the catalytic converter are suspended from the vehicle body at three points, but there is room for improvement in reducing vibration.

[0005] The present disclosure has been made in view of the above, and an object thereof is to provide a support structure for an exhaust muffler that can reduce the vibration of a vehicle.

Means for Solving the Problems

[0006] The support structure of the exhaust muffler according to the present disclosure includes an engine, a catalytic converter and an exhaust muffler suspended below the vehicle, a first exhaust pipe connecting an end of the engine and an end of the catalytic converter, a second exhaust pipe connecting an end of the catalytic converter and an end of the exhaust muffler, a first elastic body supporting one end of the exhaust muffler, a second elastic body supporting the other end of the exhaust muffler, and a third elastic body supporting one or the other end of the catalytic converter, and the rigidity of the third elastic body is lower than the rigidity of either the first elastic body or the second elastic body.

Advantages of the Invention

[0007] According to the present disclosure, vibrations of the vehicle can be reduced.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0009] The support structure of the exhaust muffler according to the embodiment of the present disclosure will be described with reference to the drawings. Note that the components in the following embodiments include those that can be replaced by those skilled in the art and are easy to replace, or those that are substantially the same.

[0010] (Support Structure of Exhaust Muffler) The support structure of the exhaust muffler according to the embodiment will be described with reference to FIGS. 1 and 2. The support structure of the exhaust muffler according to the embodiment is a structure for supporting an exhaust muffler (muffler) mounted on a vehicle.

[0011] As shown in FIG. 1, the support structure 1 includes an engine 11, a catalytic converter 12, an exhaust muffler 13, a first exhaust pipe 14, a second exhaust pipe 15, a first elastic body 16, a second elastic body 17, and a third elastic body 18. In this support structure 1, the engine 11, the catalytic converter 12, and the exhaust muffler 13 are arranged adjacent to each other in the longitudinal direction of the vehicle.

[0012] The engine 11 is a driving source of the vehicle. The catalytic converter 12 is, for example, an underfloor type catalyst and is arranged in the exhaust passage of the engine 11. Further, the catalytic converter 12 is arranged in front of the exhaust muffler 13 in the longitudinal direction of the vehicle. Also, the catalytic converter 12 is suspended below the vehicle through a suspended portion 121. The suspended portion 121 is provided at one end (the upstream end) of the catalytic converter 12.

[0013] The exhaust muffler 13 is for suppressing exhaust noise. This exhaust muffler 13 is suspended below the vehicle through suspended portions 131 and 132. The suspended portion 131 is provided at one end (the upstream end) of the exhaust muffler 13. Also, the suspended portion 132 is provided at the other end (the downstream end) of the exhaust muffler 13.

[0014] The first exhaust pipe 14 connects the engine 11 and the end of the catalytic converter 12. The second exhaust pipe 15 connects the end of the catalytic converter 12 and the end of the exhaust muffler 13. Both the first exhaust pipe 14 and the second exhaust pipe 15 are formed in a curved shape, for example, having a shape bent in a U shape or an S shape.

[0015] The first elastic body 16 supports one end (the upstream end) of the exhaust muffler 13. Specifically, this first elastic body 16 is attached to the suspended portion 131 provided at the upstream end of the exhaust muffler 13.

[0016] The second elastic body 17 supports the other end (the downstream end) of the exhaust muffler 13. Specifically, this second elastic body 17 is attached to the suspended portion 132 provided at the downstream end of the exhaust muffler 13.

[0017] The third elastic body 18 supports one or the other end (the upstream or downstream end) of the catalytic converter 12. Specifically, this third elastic body 18 is attached to the suspended portion 121 provided at the upstream end of the catalytic converter 12.

[0018] Thus, in the support structure 1, the exhaust system of the engine 11 including the exhaust muffler 13 is suspended at three points on the vehicle using the first elastic body 16 and the second elastic body 17 attached to one and the other of the exhaust muffler 13, and the third elastic body 18 attached to the other part.

[0019] Also, in the support structure 1, the rigidity of the third elastic body 18 is set lower than the rigidity of either the first elastic body 16 or the second elastic body 17. That is, when the rigidity of the first elastic body 16 is Ka, the rigidity of the second elastic body 17 is Kb, and the rigidity of the third elastic body 18 is Kc, it is set to "Kc < Ka and Kc < Kb". Note that the rigidity of the first elastic body 16, the second elastic body 17, and the third elastic body 18 can be adjusted by changing their materials, sizes, etc.

[0020] Here, FIG. 2 is a diagram for explaining the propagation of vibration in the support structure 1. For example, when the engine 11 operates, composite vibrations such as torque fluctuations caused by repeating the “exhaust stroke”, “intake stroke”, “compression stroke”, and “expansion stroke”, and inertial force vibrations associated with the reciprocation of the piston are generated, and vibrations are applied to the fastening portions of the first exhaust pipe 14 and the second exhaust pipe 15.

[0021] On the other hand, the entire support structure 1 including the exhaust muffler 13 has a plurality of resonance frequencies, and when vibrations are applied at frequencies close to its resonance frequencies, the inherent vibration modes are excited. Among these vibration modes, the one with the largest amplitude is often the fundamental vibration with the longest wavelength and the fewest nodes. This is a vibration with the following characteristics.

[0022] The connection point between the first exhaust pipe 14 and the engine 11 (see (1) in FIG. 2) becomes a fixed end (node) because it is constrained by the engine 11. Also, the center of gravity point of the exhaust muffler 13 (see (5) in FIG. 2) becomes a node because of its large inertia. In this case, the upstream end (see (4) in FIG. 2) and the downstream end (see (6) in FIG. 2) of the exhaust muffler 13 have small amplitudes because they are close to the nodes, and the other parts (see (2) and (3) in FIG. 2) have large amplitudes because they are close to the antinodes.

[0023] The transmission force transmitted to the vehicle body becomes stronger as the rigidity of the elastic bodies (the first elastic body 16, the second elastic body 17, and the third elastic body 18) is greater. Therefore, if the rigidity of these elastic bodies can be reduced, it becomes difficult for the force to be transmitted to the body. However, since these elastic bodies need to support the weight of the support structure 1, there is also a limit to reducing the rigidity.

[0024] Therefore, in the support structure 1, the rigidity of the elastic body provided at the support point with a small vibration amplitude is increased, and correspondingly, the rigidity of the elastic body provided at the support point with a large vibration amplitude is decreased. That is, the rigidity Kc of the third elastic body 18 provided outside the exhaust muffler 13 is made smaller than the rigidity Ka of the first elastic body 16 provided on the upstream side of the exhaust muffler 13 and the rigidity Kb of the second elastic body 17 provided on the downstream side of the exhaust muffler 13 (Kc < Ka and Kc < Kb). Thereby, it is possible to achieve both the support of the weight of the support structure 1 and the suppression of the vibration propagation to the vehicle body.

[0025] According to the support structure of the exhaust muffler according to the embodiment described above, by making the rigidity of the third elastic body 18 lower than the rigidity of either the first elastic body 16 or the second elastic body 17, the vibration of the vehicle can be reduced.

[0026] (Modification Example 1) A modification example 1 of the support structure of the exhaust muffler according to the embodiment will be described with reference to FIG. 3. The support structure 1A of the exhaust muffler according to this modification example is the same as the above-described support structure 1 in that it includes an engine 11, a catalytic converter 12, an exhaust muffler 13, a first exhaust pipe 14, and a second exhaust pipe 15.

[0027] On the other hand, in the support structure 1A, the exhaust system of the engine 11 including the exhaust muffler 13 is suspended from the vehicle at two points using the first elastic body 16 attached to one side (the upstream end) of the exhaust muffler 13 and the third elastic body 18 attached to the other part. Also, in the support structure 1A, the rigidity of the third elastic body 18 is set lower than the rigidity of the first elastic body 16. That is, when the rigidity of the first elastic body 16 is Ka and the rigidity of the third elastic body 18 is Kc, it is set to "Kc < Ka".

[0028] Also in the support structure 1A of the exhaust muffler having such a configuration, by making the rigidity of the third elastic body 18 lower than the rigidity of the first elastic body 16, the vibration of the vehicle can be reduced.

[0029] (Modification Example 2) Regarding Modification Example 2 of the support structure of the exhaust muffler according to the embodiment, it will be described with reference to FIG. 4. The support structure 1B of the exhaust muffler according to this modification example is the same as the above-described support structure 1 in that it includes an engine 11, a catalytic converter 12, an exhaust muffler 13, a first exhaust pipe 14, and a second exhaust pipe 15.

[0030] On the other hand, in the support structure 1B, the exhaust system of the engine 11 including the exhaust muffler 13 is suspended at two points on the vehicle using a second elastic body 17 attached to the other side (downstream end) of the exhaust muffler 13 and a third elastic body 19 attached to the other parts. This third elastic body 19 is attached to a suspended portion 122 provided at the downstream end of the catalytic converter 12. Further, in the support structure 1B, the rigidity of the third elastic body 19 is set lower than the rigidity of the second elastic body 17. That is, when the rigidity of the second elastic body 17 is Kb and the rigidity of the third elastic body 19 is Kc, it is set to "Kc < Kb".

[0031] Also in the support structure 1B of the exhaust muffler having such a configuration, by making the rigidity of the third elastic body 19 lower than the rigidity of the second elastic body 17, the vibration of the vehicle can be reduced.

[0032] (Modification Example 3) Regarding Modification Example 3 of the support structure of the exhaust muffler according to the embodiment, it will be described with reference to FIG. 5. The support structure 1C of the exhaust muffler according to this modification example is the same as the above-described support structure 1 in that it includes an engine 11, a catalytic converter 12, an exhaust muffler 13, a first exhaust pipe 14, and a second exhaust pipe 15.

[0033] On the other hand, in the support structure 1C, the exhaust system of the engine 11 including the exhaust muffler 13 is suspended from the vehicle at two points by using a second elastic body 17 attached to the other side (downstream end) of the exhaust muffler 13 and a third elastic body 20 attached to the other parts. This third elastic body 20 is attached to a suspended part 151 provided on the second exhaust pipe 15. Further, in the support structure 1C, the rigidity of the third elastic body 20 is set lower than the rigidity of the second elastic body 17. That is, when the rigidity of the second elastic body 17 is Kb and the rigidity of the third elastic body 20 is Kc, it is set as "Kc < Kb".

[0034] Even in the support structure 1C of the exhaust muffler having such a configuration, by making the rigidity of the third elastic body 20 lower than the rigidity of the second elastic body 17, the vibration of the vehicle can be reduced.

[0035] (Modification Example 4) A modification example 4 of the support structure of the exhaust muffler according to the embodiment will be described with reference to FIG. 6. The support structure 1D of the exhaust muffler according to this modification example is the same as the above-described support structure 1 in that it includes an engine 11, a catalytic converter 12, an exhaust muffler 13, a first exhaust pipe 14A, and a second exhaust pipe 15A.

[0036] On the other hand, in the support structure 1D, the first exhaust pipe 14A and the second exhaust pipe 15A are formed in a straight line. Further, in the support structure 1D, the exhaust system of the engine 11 including the exhaust muffler 13 is suspended from the vehicle at three points by using a first elastic body 16 attached to one side (upstream end) of the exhaust muffler 13, a second elastic body 17 attached to the other side (downstream end) of the exhaust muffler 13, and a third elastic body 18 attached to the other parts. Further, in the support structure 1D, the rigidity of the third elastic body 18 is set lower than the rigidity of either the first elastic body 16 or the second elastic body 17. That is, when the rigidity of the first elastic body 16 is Ka, the rigidity of the second elastic body 17 is Kb, and the rigidity of the third elastic body 18 is Kc, it is set as "Kc < Ka and Kc < Kb".

[0037] Also in the support structure 1D of the exhaust silencer having such a configuration, by making the rigidity of the third elastic body 18 lower than the rigidities of the first elastic body 16 and the second elastic body 17, vibrations of the vehicle can be reduced.

[0038] Further effects and modifications can be easily derived by those skilled in the art. Therefore, the broader aspects of the present invention are not limited to the specific details and representative embodiments shown and described above. Accordingly, various changes are possible without departing from the spirit or scope of the general inventive concept defined by the appended claims and their equivalents.

Explanation of Reference Numerals

[0039] 1, 1A, 1B, 1C, 1D Support structure 11 Engine 12 Catalytic converter 121, 122 Suspended portions 13 Exhaust silencer 131, 132 Suspended portions 14, 14A First exhaust pipe 15, 15A Second exhaust pipe 151 Suspended portion 16 First elastic body 17 Second elastic body 18, 19, 20 Third elastic body

Claims

【Claim 1】 An engine, A catalytic converter and an exhaust muffler suspended below the vehicle, A first exhaust pipe connecting an end of the engine and an end of the catalytic converter, A second exhaust pipe connecting an end of the catalytic converter and an end of the exhaust muffler, A first elastic body supporting one end of the exhaust muffler, A second elastic body supporting the other end of the exhaust muffler, A third elastic body supporting one or the other end of the catalytic converter, comprising, The rigidity of the third elastic body is lower than the rigidity of either the first elastic body or the second elastic body, A support structure for an exhaust muffler.

Images