Exhaust gas circulating valve

Abstract

The utility model relates to a waste gas circulating valve which comprises a rotating shaft, a valve plate, a lining, a shell and a first bearing. The bushing is made of a first material. The housing covers the outside of the bushing and is made of a second material that is more corrosion resistant than the first material. The bushing includes a through hole serving as an exhaust gas passage, and a first shaft hole and a second shaft hole disposed opposite to each other perpendicular to the through hole. The valve plate is contained in the through hole, and the rotating shaft is contained in the first rotating shaft hole and the second rotating shaft hole and can rotate in the first rotating shaft hole and the second rotating shaft hole. The bushing also includes a first bearing seat portion, and the housing includes a third bearing seat portion adjacent thereto. The first bearing is arranged in the first bearing seat part and the third bearing seat part in a press fit mode and supports the first end of the rotating shaft. A first concave part is arranged at the position, adjacent to the bottom face of the first bearing seat part, of the inner circumferential face of the first bearing seat part so that the first bearing can be pressed in conveniently, and the bottom face of the first bearing seat part can abut against the end face of the first bearing. Therefore, the corrosion resistance of the waste gas channel is improved at lower cost, and the sealing between parts is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of motor vehicles, and more particularly to an exhaust gas recirculation valve. Background Art

[0002] The exhaust gas recirculation valve directs engine exhaust gas to the engine's intake manifold for combustion. By absorbing some of the heat generated by combustion, the exhaust gas reduces combustion temperature and pressure, thereby reducing the formation of nitrogen oxides. Therefore, the exhaust gas recirculation valve improves engine combustion efficiency and reduces nitrogen oxide emissions, making it a key component for achieving energy conservation and emission reduction in motor vehicles.

[0003] Typically, an exhaust gas recirculation valve consists of a housing and an end cap secured together. The space formed by these two components houses a motor and a gear transmission mechanism. The housing includes a through-hole for the exhaust gas passage, within which the valve disc is received and secured to a rotating shaft. Driven by the motor, the shaft rotates via the gear transmission mechanism, driving the valve disc to open and close the exhaust gas passage, thereby controlling the amount of exhaust gas entering the engine.

[0004] Chlorine in exhaust gas can corrode exhaust gas recirculation valve components, causing shaft rotation problems or valve plate jamming, which can affect engine operation. Therefore, improving the corrosion resistance of the exhaust gas passageway through which the exhaust gas flows and improving the seals between exhaust gas recirculation valve components are key challenges. Utility Model Content

[0005] The present invention aims to solve at least one aspect of the above-mentioned problems in the prior art.

[0006] To this end, the present invention proposes an exhaust gas recirculation valve, comprising a rotating shaft and a valve plate fixed to the rotating shaft, wherein the rotating shaft comprises a first end and a second end, and is characterized in that the exhaust gas recirculation valve further comprises:

[0007] a bushing made of a first material, the bushing including a through-hole serving as an exhaust gas passage and a first rotating shaft hole and a second rotating shaft hole arranged opposite to each other perpendicular to the through-hole, the valve plate being received in the through-hole, the rotating shaft being received in the first rotating shaft hole and the second rotating shaft hole and being rotatable therein, the bushing further including a first bearing seat portion, the first bearing seat portion including a bottom surface extending perpendicularly to the first rotating shaft hole and an inner peripheral surface extending from a peripheral edge of the bottom surface of the first bearing seat portion in a direction away from the through-hole;

[0008] a shell covering the outside of the bushing, the shell being made of a second material, the first material being more corrosion-resistant than the second material, and the shell correspondingly comprising a third bearing seat portion adjacent to the first bearing seat portion;

[0009] a first bearing, the first bearing being press-fitted into the first bearing seat portion and the third bearing seat portion and configured to support the first end of the rotating shaft;

[0010] The inner circumferential surface of the first bearing seat is provided with a first recessed portion at a position adjacent to the bottom surface of the first bearing seat, so as to facilitate the pressing-in of the first bearing so that the bottom surface of the first bearing seat abuts against the end surface of the first bearing.

[0011] According to the present invention, by adding a bushing made of a more corrosion-resistant material, the corrosion resistance of the exhaust gas passage through which the exhaust gas flows is improved. Furthermore, by allowing the bottom surface of the first bearing seat to abut against the end surface of the first bearing, a seal is formed between the bottom surface of the first bearing seat and the end surface of the first bearing, preventing exhaust gas from leaking through the gap between the rotating shaft and the inner surface of the shaft hole of the bushing.

[0012] In a preferred embodiment, the first recessed portion is configured as a first annular groove that is continuous along the circumference of the inner circumferential surface of the first bearing seat. Preferably, the first annular groove has an arc-shaped longitudinal cross-section. An annular groove with an arc-shaped longitudinal cross-section is easier to process.

[0013] In a preferred embodiment, the bushing is made of stainless steel, and / or the housing is made of an aluminum alloy. Preferably, the housing is die-cast over the bushing. This allows for the corrosion-resistant exhaust gas recirculation valve to be manufactured at a relatively low cost and in a simple manner.

[0014] In a preferred embodiment, the sleeve also includes a second bearing seat portion, the second bearing seat portion includes a bottom surface extending perpendicular to the second shaft hole and an inner circumferential surface extending from the periphery of the bottom surface of the second bearing seat portion in a direction away from the through hole, and the shell correspondingly includes a fourth bearing seat portion adjacent to the second bearing seat portion, and the exhaust gas recirculation valve also includes a second bearing, the second bearing is press-fitted in the second bearing seat portion and the fourth bearing seat portion, and is used to support the second end of the shaft, and the inner circumferential surface of the second bearing seat portion is provided with a second recessed portion at a position adjacent to the bottom surface of the second bearing seat portion.

[0015] In a preferred embodiment, the second recessed portion is configured as a second annular groove continuous along the circumferential direction of the inner circumferential surface of the second bearing seat portion. Preferably, the second annular groove has an arc-shaped longitudinal cross-section.

[0016] In a preferred embodiment, a gasket is disposed between the bottom surface of the second bearing seat and the end surface of the second bearing. Due to the elasticity of the gasket, the axial position of the rotating shaft and, consequently, the position of the valve disc can be adjusted, thereby avoiding excessive friction between the valve disc and the bushing caused by improper positioning of the valve disc.

[0017] In a preferred embodiment, the bushing further includes an exhaust gas flow detection hole located downstream of the valve plate in the direction of exhaust gas flow. This allows convenient detection of the flow rate of exhaust gas entering the engine intake manifold using a flow sensor connected to the exhaust gas flow detection hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be described in detail below by way of non-limiting embodiments with reference to the accompanying drawings, in which:

[0019] Figure 1 is a perspective view of an exhaust gas recirculation valve according to an exemplary embodiment of the present invention;

[0020] Figure 2 yes Figure 1 A longitudinal sectional view of the exhaust gas recirculation valve is shown, in which part of the structure is removed to more clearly show the innovative features of the present invention;

[0021] Figure 3 yes Figure 2 An enlarged view of part A in FIG;

[0022] Figure 4 yes Figure 2 An enlarged view of part B in FIG;

[0023] Figure 5 yes Figure 1 A perspective view of a bushing for an exhaust gas recirculation valve is shown; and

[0024] Figure 6 yes Figure 5 A longitudinal section of the bushing is shown.

[0025] The accompanying drawings are schematic only and are not necessarily drawn to scale. They show only those parts necessary to illustrate the present invention, and other parts may be omitted or mentioned only briefly. In addition to the parts or parts shown in the accompanying drawings, the present invention may also include other parts or parts. DETAILED DESCRIPTION

[0026] In the following description, many specific details are set forth to provide those skilled in the art with a more comprehensive understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be implemented without some of these specific details. Furthermore, it should be understood that the present invention is not limited to the specific embodiments described. Rather, any combination of the following features and elements may be considered to implement the present invention, regardless of whether they relate to different embodiments. Therefore, the following features, embodiments, and advantages are provided for illustrative purposes only and should not be considered as elements or limitations of the claims unless expressly set forth in the claims.

[0027] Figure 1 The exhaust gas recirculation valve 100 according to an exemplary embodiment of the present invention is shown in a perspective view. Figure 1 As shown, the exhaust gas recirculation valve 100 includes a housing 1 and an end cover 2, and the housing 1 and the end cover 2 are fixed to each other. A motor and a gear transmission mechanism (not shown) are accommodated in the internal space formed by the housing 1 and the end cover 2. An exhaust gas channel 3 and a rotating shaft hole 4 are formed in the housing 1. The exhaust gas recirculation valve 100 also includes a rotating shaft 5 and a valve plate 6. The rotating shaft 5 is received in the rotating shaft hole 4 and can be rotated by the motor via the gear transmission mechanism. The valve plate 6 is arranged in the exhaust gas channel 3 and fixed to the rotating shaft 5, so that it can rotate driven by the rotating shaft 5 to open and close the exhaust gas channel 3, thereby controlling the amount of exhaust gas entering the engine.

[0028] According to the present invention, the exhaust gas recirculation valve 100 further includes a bushing 7, and the housing 1 is covered on the outside of the bushing 7. Figure 2 and 6 As shown, bushing 7 includes a through hole 70 forming exhaust passage 3, and first and second rotation shaft holes 71 and 72 arranged perpendicularly to through hole 70 and facing each other. Rotation shaft 5 is received in first and second rotation shaft holes 71 and 72 and is rotatable therein. Valve disc 6 is received in through hole 70 and fixed to rotation shaft 5, thereby being driven by rotation shaft 5 to rotate.

[0029] The bushing 7 is made of a first material and the housing 1 is made of a second material, and the first material is more corrosion-resistant than the second material. Preferably, the housing 1 is covered on the outside of the bushing 7 by die-casting. During the operation of the exhaust gas recirculation valve 100, the exhaust gas enters the engine intake manifold through the through hole 70 under the control of the valve plate 6. In the present invention, the exhaust gas only contacts the bushing 7 and not the housing 1. Therefore, the bushing 7 made of a more corrosion-resistant material enables the exhaust gas recirculation valve 100 to have better working performance. Generally speaking, more corrosion-resistant materials are more expensive, so this also allows the use of more expensive materials to be reduced, thereby reducing production costs.

[0030] For example, the bushing 7 is made of stainless steel, and the housing 1 is made of an aluminum alloy. Preferably, the housing 1 is die-casted onto the bushing 7, thereby simplifying the manufacture of the exhaust gas recirculation valve. However, it should be understood that the first and second materials may be any suitable materials known in the art, and the housing 1 and bushing 7 may be secured together in other suitable manners.

[0031] like Figure 2 As shown, the shaft 5 has a first end 51 and a second end 52. Figure 2 In the embodiment shown, the exhaust gas recirculation valve 100 further includes a first bearing 8 and a second bearing 9. The first bearing 8 is used to support the first end 51 of the rotating shaft 5, and the second bearing 9 is used to support the second end 52 of the rotating shaft 5.

[0032] like Figure 6 As shown, the bushing 7 further includes a first bearing seat portion 73 and a second bearing seat portion 74. The first bearing seat portion 73 includes a bottom surface 76 extending perpendicularly to the first shaft hole 71 and an inner peripheral surface 75 extending from the periphery of the bottom surface 76 in a direction away from the through hole 70. The second bearing seat portion 74 includes a bottom surface 78 extending perpendicularly to the second shaft hole 72 and an inner peripheral surface 77 extending from the periphery of the bottom surface 78 in a direction away from the through hole 70. Figures 2 to 4 As shown, the housing 1 accordingly includes a third bearing seat portion 11 adjacent to the first bearing seat portion 73 and a fourth bearing seat portion 12 adjacent to the second bearing seat portion 74. The first bearing 8 is press-fitted into the first bearing seat portion 73 and the third bearing seat portion 11, and the second bearing 9 is press-fitted into the second bearing seat portion 74 and the fourth bearing seat portion 12.

[0033] like Figure 3 As shown, the outer circumferential surface 81 of the first bearing 8 abuts against the inner circumferential surface 75 of the first bearing seat 73 and the inner circumferential surface 13 of the third bearing seat 11, and the end surface 82 of the first bearing 8 abuts against the bottom surface 76 of the first bearing seat 73. Because the end surface 82 of the first bearing 8 abuts against the bottom surface 76 of the first bearing seat 73, leakage of exhaust gas through the first shaft hole 71 between the shaft 5 and the bushing 7 is prevented.

[0034] Since more corrosion-resistant materials usually have higher hardness, when the first bearing 8 is pressed into the third bearing seat 11 and the first bearing seat 73 in sequence, it may be difficult to press it into the first bearing seat 73, making it difficult for the end face 82 of the first bearing 8 to rest against the bottom face 76 of the first bearing seat 73, so that the exhaust gas leaks through the gap between the end face 82 of the first bearing 8 and the bottom face 76 of the first bearing seat 73.

[0035] To this end, advantageously, the inner circumferential surface 75 of the first bearing seat portion 73 is provided with a first recessed portion at a position adjacent to the bottom surface 76, thereby forming a gap between the inner circumferential surface 75 of the first bearing seat portion 73 and the outer circumferential surface 81 of the first bearing 8, that is, the contact area therebetween is small, which is conducive to reducing the pressing resistance of the first bearing 8, thereby facilitating the first bearing 8 to be pressed into place, so that the end face 82 of the first bearing 8 can be tightly against the bottom surface 76 of the first bearing seat portion 73, thereby avoiding exhaust gas leakage.

[0036] Preferably, if Figure 3 、 5 As shown in FIG6 , the first recessed portion is provided as a first annular groove 75′ which is continuous along the circumferential direction of the inner circumferential surface 75 of the first bearing seat portion 73. Figure 6 As shown, the first annular groove 75' has an arc-shaped longitudinal section. An annular groove of this shape is easy to process. However, it should be understood that any suitable shape is possible.

[0037] like Figure 4 As shown, the outer circumferential surface 91 of the second bearing 9 abuts against the inner circumferential surface 77 of the second bearing seat 74 and the inner circumferential surface 14 of the fourth bearing seat 12. Because a portion of the outer circumferential surface 91 of the second bearing 9 abuts against the inner circumferential surface 77 of the second bearing seat 74, leakage of exhaust gas through the second shaft hole 72 between the shaft 5 and the bushing 7 is prevented.

[0038] Advantageously, as Figure 4 As shown, a gasket 10 can be provided between the bottom surface 78 of the second bearing seat 74 and the end surface 92 of the second bearing 9. Due to the elasticity of the gasket 10, the axial position of the rotating shaft 5 and the position of the valve disc 6 can be adjusted, thereby avoiding excessive friction between the valve disc 6 and the bushing 7 due to improper position of the valve disc 6.

[0039] To facilitate press-fitting of the gasket 10, preferably, as described above with respect to the first bearing seat 73, the inner circumferential surface 77 of the second bearing seat 74 is provided with a second recessed portion at a location adjacent to the bottom surface 78. For example, the second recessed portion is provided as a second annular groove 77' that is continuous along the circumference of the inner circumferential surface 77 of the second bearing seat 74. The second annular groove 77' preferably has an arc-shaped longitudinal cross-section.

[0040] like Figure 3 and 4As shown, the length of the contact between the outer circumferential surface 91 of the second bearing 9 and the inner circumferential surface 77 of the second bearing seat 74 is larger than the length of the contact between the outer circumferential surface 81 of the first bearing 8 and the inner circumferential surface 75 of the first bearing seat 73. The leakage of exhaust gas through the second shaft hole 72 between the shaft 5 and the bushing 7 is avoided by the abutment between the outer circumferential surface 91 of the second bearing 9 and the inner circumferential surface 77 of the second bearing seat 74, rather than the leakage of exhaust gas at the first shaft hole 71 being avoided by the abutment between the end face 82 of the first bearing 8 and the bottom face 76 of the first bearing seat 73.

[0041] Alternatively, to facilitate the press-fitting operation of the second bearing 9, the second bearing seat 74 may be designed similarly to the first bearing seat 73, that is, the outer circumferential surface 91 of the second bearing 9 abuts against the inner circumferential surface 77 of the second bearing seat 74 over only a short contact length, while the end surface 92 of the second bearing 9 abuts against the bottom surface 78 of the second bearing seat 74. In this case, leakage of exhaust gas through the second shaft hole 72 via the shaft 5 and the bushing 7 is prevented by the abutment between the end surface 92 of the second bearing 9 and the bottom surface 78 of the second bearing seat 74.

[0042] like Figure 1 、 2 , 5 and 6, the bushing 7 further includes an exhaust gas flow detection hole 79, which is located downstream of the valve plate 6 in the exhaust gas flow direction. An exhaust gas sensor (not shown) can be connected to the exhaust gas flow detection hole 79 to detect the flow rate of exhaust gas entering the engine intake manifold.

[0043] Although the present invention is disclosed above with reference to preferred embodiments, the present invention is not limited thereto. Any changes and modifications made by those skilled in the art without departing from the spirit and scope of the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope defined by the claims.

Claims

1. An exhaust gas recirculation valve (100), comprising a rotating shaft (5) and a valve plate (6) fixed to the rotating shaft (5), wherein the rotating shaft (5) comprises a first end (51) and a second end (52), and is characterized in that: The exhaust gas recirculation valve (100) further comprises: A bushing (7), wherein the bushing (7) is made of a first material, the bushing (7) includes a through hole (70) serving as an exhaust gas passage and a first rotating shaft hole (71) and a second rotating shaft hole (72) arranged opposite to each other perpendicular to the through hole (70), the valve plate (6) is received in the through hole (70), the rotating shaft (5) is received in the first rotating shaft hole (71) and the second rotating shaft hole (72) and is rotatable in the first rotating shaft hole (71) and the second rotating shaft hole (72), the bushing (7) further includes a first bearing seat portion (73), the first bearing seat portion (73) includes a bottom surface (76) extending perpendicular to the first rotating shaft hole (71) and an inner peripheral surface (75) extending from the peripheral edge of the bottom surface (76) of the first bearing seat portion (73) in a direction away from the through hole (70); a shell (1) covering the outside of the bushing (7), the shell (1) being made of a second material, the first material being more corrosion-resistant than the second material, and the shell (1) correspondingly comprising a third bearing seat portion (11) adjacent to the first bearing seat portion (73); a first bearing (8), the first bearing (8) being press-fitted into the first bearing seat (73) and the third bearing seat (11), and being used to support the first end (51) of the rotating shaft (5); The inner peripheral surface (75) of the first bearing seat (73) is provided with a first recessed portion at a position adjacent to the bottom surface (76) of the first bearing seat (73) to facilitate the pressing of the first bearing (8) so that the bottom surface (76) of the first bearing seat (73) abuts against the end surface (82) of the first bearing (8).

2. The exhaust gas recirculation valve (100) according to claim 1, characterized in that The first recessed portion is configured as a first annular groove (75') continuous along the circumferential direction of the inner circumferential surface (75) of the first bearing seat portion (73).

3. The exhaust gas recirculation valve (100) according to claim 2, characterized in that The first annular groove (75') has an arc-shaped longitudinal section.

4. The exhaust gas recirculation valve (100) according to any one of claims 1 to 3, characterized in that The bushing (7) is made of stainless steel, and / or the housing (1) is made of aluminum alloy.

5. The exhaust gas recirculation valve (100) according to claim 4, characterized in that The housing (1) is covered on the outside of the bushing (7) by die casting.

6. The exhaust gas recirculation valve (100) according to any one of claims 1 to 3, characterized in that The bushing (7) also includes a second bearing seat (74), the second bearing seat (74) includes a bottom surface (78) extending perpendicular to the second shaft hole (72) and an inner peripheral surface (77) extending from the periphery of the bottom surface (78) of the second bearing seat (74) in a direction away from the through hole (70), the housing (1) correspondingly includes a fourth bearing seat (12) adjacent to the second bearing seat (74), the exhaust gas recirculation valve (100) also includes a second bearing (9), the second bearing (9) is press-fitted in the second bearing seat (74) and the fourth bearing seat (12), and is used to support the second end (52) of the shaft (5), and the inner peripheral surface (77) of the second bearing seat (74) is provided with a second recessed portion at a position adjacent to the bottom surface (78) of the second bearing seat (74).

7. The exhaust gas recirculation valve (100) according to claim 6, characterized in that The second recessed portion is configured as a second annular groove (77') continuous along the circumferential direction of the inner circumferential surface (77) of the second bearing seat portion (74).

8. The exhaust gas recirculation valve (100) according to claim 7, characterized in that The second annular groove (77') has an arc-shaped longitudinal section.

9. The exhaust gas recirculation valve (100) according to claim 6, characterized in that A gasket (10) is provided between the bottom surface (78) of the second bearing seat portion (74) and the end surface (92) of the second bearing (9).

10. The exhaust gas recirculation valve (100) according to any one of claims 1 to 3, characterized in that The bushing (7) further comprises an exhaust gas flow detection hole (79), and the exhaust gas flow detection hole (79) is located downstream of the valve plate (6) in the exhaust gas flow direction.

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