Exhaust system front muffler and exhaust system

Abstract

The application provides an exhaust system front muffler and an exhaust system, and the exhaust system front muffler comprises an air inlet pipe, an outer cylinder, an air outlet end cover, an air outlet pipe and an inner cylinder; the air inlet pipe, the outer cylinder, the air outlet end cover and the air outlet pipe are sequentially connected, and the inner cylinder is arranged in the inner portion of the outer cylinder; the other end of the air inlet pipe is welded and fixed with one end of the outer cylinder, the outer surface of one end of the inner cylinder is provided with a gasket, the gasket is in gap cooperation with the outer cylinder, and the end portion of the air inlet pipe and the end portion of the inner cylinder exist a deformation gap in the axial direction; the other end of the inner cylinder, the other end of the air outlet end cover and one end of the air outlet pipe are welded and fixed. The above exhaust system front muffler can not only avoid the knocking of the inner cylinder and the outer cylinder in the muffler during the driving of the automobile to cause abnormal sound, but also can improve the thermal fatigue fracture of the exhaust pipe.

Description

Technical Field

[0001] This invention relates to the field of automotive exhaust system technology, and in particular to a front muffler and exhaust system for an exhaust system. Background Technology

[0002] Currently, automobile exhaust temperatures are generally high, with some exhaust systems having front muffler temperatures exceeding 750°C.

[0003] The front muffler of the exhaust system is prone to expansion of the exhaust pipe at high temperatures, which can cause thermal fatigue fracture of the exhaust pipe.

[0004] Especially when there is sound-absorbing cotton in the front muffler pipe, on the one hand, the sound-absorbing cotton can effectively reduce noise, but it will also significantly reduce the heat dissipation of the muffler exhaust pipe, causing the temperature of the exhaust pipe inside the muffler to rise. Under high temperature, the exhaust pipe expands axially, and the exhaust pipe inside the muffler is prone to thermal fatigue fracture failure, which will cause abnormal noise inside the muffler and affect the NVH performance of the car.

[0005] In view of the above, there is a need for a front muffler that improves the thermal fatigue fracture of the exhaust pipe inside the muffler. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a front muffler and exhaust system for an exhaust system. This design not only prevents abnormal noises caused by collisions between the inner and outer cylinders of the muffler during vehicle operation, but also allows for expansion gaps to accommodate the free expansion of the inner cylinder at high temperatures, reducing stress on the exhaust pipe and improving its resistance to thermal fatigue fracture. The technical solution adopted by this invention is as follows:

[0007] An exhaust system front muffler includes an intake pipe, an outer cylinder, an exhaust end cap, an exhaust pipe, and an inner cylinder;

[0008] The air inlet pipe, outer cylinder, air outlet end cap, and air outlet pipe are connected in sequence, and the inner cylinder is disposed inside the outer cylinder.

[0009] The other end of the air intake pipe is welded and fixed to one end of the outer cylinder. A washer is provided on the outer surface of one end of the inner cylinder. The washer is clearance-fitted with the outer cylinder. There is a deformation gap between the end of the air intake pipe and the end of the inner cylinder in the axial direction.

[0010] The other end of the inner cylinder, the other end of the air outlet cover, and one end of the air outlet pipe are welded and fixed.

[0011] Furthermore, one end of the outer cylinder gradually narrows to form a first contraction section, an outer cylinder middle diameter section, a second contraction section, and an outer cylinder small diameter section connected in sequence, with the outer cylinder middle diameter section and the outer cylinder small diameter section arranged coaxially;

[0012] The small-diameter section of the outer cylinder is welded and fixed to the air inlet pipe, and the middle-diameter section of the outer cylinder is clearance-fitted with the gasket.

[0013] Furthermore, the inner cylinder includes a first straight segment, a bent segment, and a second straight segment connected in sequence. The first straight segment is arranged coaxially with the air inlet pipe, and the second straight segment is arranged coaxially with the air outlet pipe. The air inlet pipe and the air outlet pipe are not coaxial.

[0014] Furthermore, the other end of the second straight segment expands outward to form a flared section, and the other end of the air outlet cap gradually narrows inward to form a third contracted section and a small diameter section of the end cap connected in sequence. The flared section, the small diameter section of the end cap, and the air outlet pipe are welded and fixed together.

[0015] Furthermore, a support member is connected between the first straight segment and the outer cylinder;

[0016] The support member divides the space between the outer cylinder and the inner cylinder into a first chamber and a second chamber. The first chamber is filled with a first sound-absorbing cotton, and the second chamber is filled with a second sound-absorbing cotton.

[0017] The outer surface of the first straight segment is provided with a first sound-absorbing hole corresponding to the first sound-absorbing cotton, and the outer surface of the second straight segment is provided with a second sound-absorbing hole corresponding to the second sound-absorbing cotton.

[0018] Furthermore, the support member includes a support body, an inner flange, and an outer flange. The support body is an annular sheet shape and is supported between the outer cylinder and the first straight segment. The inner flange is located at the inner edge of the support body and is in clearance fit with the first straight segment. The outer flange is located at the outer edge of the support body and is in transition fit with the outer cylinder.

[0019] Furthermore, the surface of the supporting body is provided with annular reinforcing ribs that protrude outwards.

[0020] Furthermore, the surface of the support body is provided with several small holes.

[0021] An exhaust system, wherein the exhaust system has a front muffler.

[0022] Advantages of this invention:

[0023] Only the intake pipe is welded and fixed to the outer cylinder, while the inner cylinder is spaced apart from the intake pipe. A gasket is installed on the outside of the inner cylinder to prevent collisions between the inner and outer cylinders during vehicle operation, which could cause abnormal noises. On the other hand, it ensures that the inner cylinder has axial expansion distance at high temperatures, which reduces the stress on the exhaust pipe and improves the situation of thermal fatigue deformation. Attached Figure Description

[0024] Figure 1This is a schematic diagram of the structural composition of the present invention.

[0025] Figure 2 This is a cross-sectional view of the present invention.

[0026] Figure 3 for Figure 2 Enlarged view of a portion of point A in the middle.

[0027] Figure 4 for Figure 2 Enlarged view of section B in the middle.

[0028] Figure 5 This is a structural diagram of the support component.

[0029] In the diagram: 100-Inlet pipe, 200-Outer cylinder, 210-First contraction section, 220-Outer cylinder middle diameter section, 230-Second contraction section, 240-Outer cylinder small diameter section, 300-Outlet end cap, 310-Third contraction section, 320-End cap small diameter section, 400-Outlet pipe, 500-Inner cylinder, 510-First straight section, 511-First silencing hole, 520-Bending section, 530-Second straight section, 531-Second silencing hole, 540-Flanged section, 600-Washer, 700-Support component, 710-Support body, 720-Inner flange, 730-Outer flange, 740-Reinforcing rib, 750-Small hole, 800-First silencing cotton, 900-Second silencing cotton. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0031] Please see the appendix Figure 1 - Appendix Figure 5 This application first proposes a front muffler and exhaust system for an exhaust system, including an intake pipe 100, an outer cylinder 200, an exhaust end cap 300, an exhaust pipe 400, and an inner cylinder 500; the intake pipe 100, outer cylinder 200, exhaust end cap 300, and exhaust pipe 400 are connected sequentially, and the inner cylinder 500 is disposed inside the outer cylinder 200; the other end of the intake pipe 100 is welded and fixed to one end of the outer cylinder 200, and a washer 600 is provided on the outer surface of one end of the inner cylinder 500, the washer 600 having a clearance fit with the outer cylinder 200, and there is a deformation gap in the axial direction between the end of the intake pipe 100 and the end of the inner cylinder 500; the other end of the inner cylinder 500, the other end of the exhaust end cap 300, and one end of the exhaust pipe 400 are welded and fixed.

[0032] In existing technology, the intake pipe 100, outer cylinder 200, and inner cylinder 500 are typically welded together. The inner cylinder 500 has no axial expansion space. During the operation of the entire exhaust system, the end of the inner cylinder 500 will deform axially during thermal fatigue. Therefore, the connection between the intake pipe and the inner and outer cylinders is a high-risk area for thermal fatigue fracture. Once the inner cylinder fails, abnormal noise will be emitted inside the muffler as the car is driven, affecting the vehicle's NVH performance.

[0033] As attached Figure 2 and attached Figure 3 As shown in the embodiment of this application, the right end of the intake pipe 100 is connected to the left end of the outer cylinder 200, the left end of the exhaust end cap 300 is welded and fixed to the right end of the outer cylinder 200, and the right end of the outer cylinder 200 is welded and fixed to the left end of the exhaust pipe 400 and the right end of the inner cylinder 500. The outer diameter of the right end of the intake pipe 100 is smaller than the outer diameter of the left end of the outer cylinder 200. After the right end of the intake pipe 100 is inserted into the left end of the outer cylinder 200, the two are welded and fixed. At this time, there is a certain distance (i.e., deformation gap) between the left end of the inner cylinder 500 and the intake pipe 100. In addition, the clearance fit between the washer 600 and the outer cylinder 200 shortens the radial distance between the inner cylinder 500 and the outer cylinder 200, and also ensures that the left end of the inner cylinder 500 does not directly contact the outer cylinder 200 or the intake pipe 100. Thus, during vehicle operation, the gasket 600 prevents the inner cylinder 500 from colliding with the outer cylinder 200, thus avoiding abnormal noise. It also allows the inner cylinder 500 to expand freely in the axial direction at high temperatures, especially preventing thermal fatigue fracture at the connection between the intake pipe 100 and the outer cylinder 200.

[0034] Please see the appendix Figure 3 The outer cylinder 200 gradually narrows at one end to form a first contraction section 210, an outer cylinder middle diameter section 220, a second contraction section 230, and an outer cylinder small diameter section 240 connected in sequence. The outer cylinder middle diameter section 220 and the outer cylinder small diameter section 240 are arranged coaxially. The outer cylinder small diameter section 240 is welded and fixed to the air inlet pipe 100, and the outer cylinder middle diameter section 220 is clearance-fitted with the gasket 600.

[0035] Specifically, the first contraction section 210 and the second contraction section 230 form a flared structure at both ends, which improves the clearance fit between the inner diameter of the middle diameter section 220 of the outer cylinder and the outer diameter of the washer 600, and from the attached Figure 2 It can be seen that the length of the middle diameter section 220 of the outer cylinder is greater than the length of the washer 600, which provides sufficient deformation gap for the expansion of the inner cylinder 500 and guides the expansion action of the inner cylinder 500. When the inner cylinder 500 expands to a certain length, the second contraction section 230 can also block the washer 600 to prevent the inner cylinder 500 from squeezing the air inlet pipe 100.

[0036] Please see the appendix Figure 2 The inner cylinder 500 includes a first straight section 510, a bent section 520 and a second straight section 530 connected in sequence. The first straight section 510 is coaxially arranged with the air inlet pipe 100 and the second straight section 530 is coaxially arranged with the air outlet pipe 400. The air inlet pipe 100 and the air outlet pipe 400 are not coaxial.

[0037] In one specific embodiment, rounded transition areas are formed between the bent section 520 of the inner cylinder 500 and the first straight section 510, and between the second straight section 530, respectively, to ensure the connectivity between the sections in the inner cylinder 500. The bent section 520 is used to realize the different axis arrangements between the first straight section 510 and the second straight section 530 to adapt to the different axis installation requirements of the air inlet pipe 100 and the air outlet pipe 400.

[0038] To meet the sealing and welding requirements of the muffler outlet, please refer to the appendix. Figure 4 The other end of the second straight segment 530 expands outward to form a flared segment 540, and the other end of the air outlet end cap 300 gradually narrows inward to form a third contracted segment 310 and an end cap small diameter segment 320 connected in sequence. The flared segment 540, the end cap small diameter segment 320 and the air outlet pipe 400 are welded and fixed together.

[0039] Specifically, the exhaust end cap 300 is an eccentric end cap. Its left end is the large-diameter section, which is welded to the outer cylinder 200 in one weld. Its right end is the small-diameter section 320 of the end cap, which is welded to the flared section 540 and the exhaust pipe 400 in one weld to meet the coaxial installation requirements between the exhaust pipe 400 and the inner cylinder 500.

[0040] In this application, in order to support the inner cylinder 500 within the outer cylinder 200, a support member 700 is connected between the first straight segment 510 and the outer cylinder 200; the support member 700 divides the space between the outer cylinder 200 and the inner cylinder 500 into a first chamber and a second chamber, the first chamber being filled with a first sound-absorbing cotton 800 and the second chamber being filled with a second sound-absorbing cotton 800; a first sound-absorbing hole 511 corresponding to the first sound-absorbing cotton 800 is provided on the outer surface of the first straight segment 510, and a second sound-absorbing hole 531 corresponding to the second sound-absorbing cotton 800 is provided on the outer surface of the second straight segment 530.

[0041] As attached Figure 2 and attached Figure 5As shown in this application, since the right end of the inner cylinder 500 is fixed to the air outlet cover 300 and the air outlet pipe 400, while its left end is a free end, a support member 700 can be provided at the first straight section 510 near the left end of the inner cylinder 500 to support the inner cylinder 500, thus saving the number of support members 700 used. At the same time, the first sound-absorbing cotton 800 and the second sound-absorbing cotton 900 filled in the two cavities formed on both sides of the support member 700 can cooperate with the first sound-absorbing hole 511 and the second sound-absorbing hole 531 respectively to achieve the effect of eliminating standing waves and reducing flow noise.

[0042] As an embodiment of this application, the first silencing hole portion 511 and the second silencing hole portion 531 are each composed of a plurality of silencing holes.

[0043] In one specific embodiment, as shown in the appendix Figure 5 As shown, the support member 700 includes a support body 710, an inner flange 720, and an outer flange 730. The support body 710 is an annular plate-shaped support between the outer cylinder 200 and the first straight segment 510. The inner flange 720 is located at the inner edge of the support body 710 and is in clearance fit with the first straight segment 510. The outer flange 730 is located at the outer edge of the support body 710 and is in transition fit with the outer cylinder 200.

[0044] In this embodiment, the inner flange 720 and the outer flange 730 are used to increase the contact area between the support member 700 and the inner and outer cylinders, improve the support stability of the inner cylinder 500, and make the plane of the support body 710 perpendicular to the axis of the first straight segment 510, so as to prevent the support body 710 from tilting and increasing the installation error between the inner cylinder 500, the outer cylinder 200, and the air outlet end cap 300.

[0045] Furthermore, in order to improve the structural strength of the support member 700, the surface of the support body 710 is provided with annular reinforcing ribs 740 protruding outward.

[0046] Furthermore, in order to connect the first chamber and the second chamber and improve the noise reduction effect, the surface of the support body 710 is provided with a number of small holes 750.

[0047] On the other hand, this application also provides an exhaust system, including the aforementioned front muffler. Applying the aforementioned front muffler to the exhaust system can prevent abnormal noises caused by the collision between the inner and outer cylinders of the muffler during vehicle operation, and improve the situation of thermal fatigue fracture of the exhaust pipe.

[0048] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An exhaust system front muffler characterized by: It comprises an air inlet pipe (100), an outer cylinder (200), an air outlet end cover (300), an air outlet pipe (400), and an inner cylinder (500); The air inlet pipe (100), the outer cylinder (200), the air outlet end cover (300), and the air outlet pipe (400) are sequentially connected, and the inner cylinder (500) is arranged inside the outer cylinder (200); One end of the right side of the air inlet pipe (100) is welded and fixed with one end of the left side of the outer cylinder (200), and the outer surface of one end of the left side of the inner cylinder (500) is provided with a gasket (600), the gasket (600) is in clearance fit with the outer cylinder (200), and there is a deformation gap in the axial direction between one end of the right side of the air inlet pipe (100) and one end of the left side of the inner cylinder (500). One end of the right side of the inner cylinder (500), one end of the right side of the air outlet end cover (300), and one end of the left side of the air outlet pipe (400) are welded and fixed.

2. The exhaust system pre-muffler of claim 1, wherein: One end of the left side of the outer cylinder (200) is gradually tapered to form a first contraction section (210), an outer cylinder medium diameter section (220), a second contraction section (230), and an outer cylinder small diameter section (240) which are sequentially connected, and the outer cylinder medium diameter section (220) and the outer cylinder small diameter section (240) are coaxially arranged; The outer cylinder small diameter section (240) is welded and fixed with the air inlet pipe (100), and the outer cylinder medium diameter section (220) is in clearance fit with the gasket (600).

3. The exhaust system pre-muffler of claim 1, wherein: The inner cylinder (500) comprises a first straight section (510), a bending section (520), and a second straight section (530) which are sequentially connected, the first straight section (510) is coaxially arranged with the air inlet pipe (100), the second straight section (530) is coaxially arranged with the air outlet pipe (400), and the air inlet pipe (100) is different in axis from the air outlet pipe (400).

4. The exhaust system pre-muffler of claim 3, wherein: One end of the right side of the second straight section (530) is outwardly expanded to form a flared section (540), one end of the right side of the air outlet end cover (300) is gradually tapered inward to form a third contraction section (310) and an end cover small diameter section (320) which are sequentially connected, and the flared section (540), the end cover small diameter section (320), and the air outlet pipe (400) are welded and fixed.

5. The exhaust system pre-muffler of claim 3, wherein: A support (700) is connected between the first straight section (510) and the outer cylinder (200); The support (700) divides the space between the outer cylinder (200) and the inner cylinder (500) into a first chamber and a second chamber, the first chamber is filled with first sound-absorbing cotton (800), and the second chamber is filled with second sound-absorbing cotton (800); A first sound-absorbing hole portion (511) corresponding to the first sound-absorbing cotton (800) is arranged on the outer surface of the first straight section (510), and a second sound-absorbing hole portion (531) corresponding to the second sound-absorbing cotton (800) is arranged on the outer surface of the second straight section (530).

6. The exhaust system pre-muffler of claim 5, wherein: The support piece (700) comprises a support body (710), an inner flange (720) and an outer flange (730), the support body (710) is annular and sheet-shaped, supported between the outer cylinder (200) and the first straight segment (510), the inner flange (720) is arranged at the inner edge of the support body (710) and gaps with the first straight segment (510), and the outer flange (730) is arranged at the outer edge of the support body (710) and transitions with the outer cylinder (200).

7. The exhaust system pre-muffler of claim 6, wherein: The surface of the support body (710) is outwardly convexly provided with an annular reinforcing rib (740).

8. The exhaust system pre-muffler of claim 6, wherein: The surface of the support body (710) is provided with a plurality of small holes (750).

9. An exhaust system characterized by: An exhaust system front muffler comprising any one of claims 1-8.

Images