Oil-gas separation mechanism for motorcycle engine

Abstract

The application provides an oil-gas separation mechanism of a motorcycle engine and belongs to the technical field of engines. The oil-gas separation mechanism of the motorcycle engine has the advantages of good oil-gas separation effect.

Description

Technical Field

[0001] This invention belongs to the field of engine technology and relates to an oil-gas separation mechanism for a motorcycle engine. Background Technology

[0002] The main function of the engine oil-gas separator is to extract the oil-gas mixture from the crankcase and separate the oil and gas using a specific method. The separated gas is either re-entered into the cylinder for combustion or expelled, while the separated oil returns to the oil pan for reuse.

[0003] Existing engine oil-gas separation mechanisms, such as the motorcycle engine with an oil-gas separation mechanism disclosed in Chinese patent literature [Patent No.: 202023239237.5; Application Publication No.: CN213980911U], include a housing, a camshaft rotatably connected inside the housing, a timing driven gear connected to one end of the camshaft, a first cavity communicating with the internal space of the housing in the middle of the timing driven gear, a second cavity communicating with the first cavity inside the camshaft, and an exhaust assembly rotatably connected to the end of the camshaft away from the timing driven gear, with a third cavity communicating with the second cavity inside the exhaust assembly.

[0004] In this type of oil-gas separator, after the gas-fuel mixture passes through the separator, a very small amount of oil enters the camshaft and forms oil droplets that condense on the inner wall of the second cavity. These oil droplets flow back into the engine housing through the gap between the camshaft and the breather valve. However, precisely because of the gap between the camshaft and the breather valve, some of the unseparated gas-fuel mixture in the housing enters the second cavity of the camshaft through this gap. This mixture carries a large amount of oil and is subsequently discharged through the breather valve and breather pipe, resulting in a large amount of oil being discharged with the exhaust gas and reducing the oil-gas separation efficiency. Summary of the Invention

[0005] The purpose of this invention is to address the aforementioned problems in the prior art by proposing an oil-gas separation mechanism for a motorcycle engine, and to solve the technical problem of how to improve the oil-gas separation effect of the oil-gas separation mechanism.

[0006] The objective of this invention can be achieved through the following technical solution: an oil-gas separation mechanism for a motorcycle engine, the engine including a housing, the oil-gas separation mechanism including a camshaft located in the housing and having an exhaust passage, characterized in that the oil-gas separation mechanism further includes an exhaust pipe and a sealing element sleeved outside the exhaust pipe, the sealing element including a sealing portion that is annularly protruding and elastic, the housing having a mounting hole, the exhaust pipe passing through the mounting hole and being axially positioned with the housing, the sealing element extending into the exhaust passage, the exhaust pipe pressing the circumferential edge of the sealing portion against the passage wall of the exhaust passage.

[0007] A centrifugal valve assembly is installed at one end of the camshaft, and the exhaust pipe is installed at the other end. After the gas-fuel mixture in the housing undergoes oil-gas separation by the centrifugal valve assembly, the oil droplets flow back into the housing, while the exhaust gas is discharged through the exhaust passage and exhaust pipe. A seal is fitted over the inner end of the exhaust pipe. As the exhaust pipe moves, it pushes the seal into the exhaust passage, causing the circumferential edge of the seal to contact the passage wall. As the exhaust pipe continues to move, the seal deforms under pressure, pressing its circumferential edge tightly against the passage wall to form a seal. Finally, the exhaust pipe is axially positioned against the housing. This seal effectively seals the gap between the camshaft and the exhaust pipe, preventing the gas-fuel mixture in the housing from entering the exhaust passage through this gap, thus improving the oil-gas separation efficiency. After separation by the centrifugal valve assembly, a very small amount of oil may enter the exhaust passage, adhering to the passage wall and forming oil droplets. This only needs to be cleaned periodically, such as during vehicle maintenance.

[0008] In the aforementioned oil-gas separation mechanism for a motorcycle engine, the seal further includes an annular body. The sealing part is located on one side of the body, and an annular buffer groove is provided on the outer circumferential side between the sealing part and the body. The sealing part is obliquely inclined outward along the direction from the body towards the sealing part. Because the sealing part is obliquely inclined outward, when it contacts and presses against the camshaft, it can move a small distance towards the buffer groove, giving it a greater rebound pressing force and improving sealing performance. This prevents the mixed gas in the housing from entering the exhaust passage through the gap, thereby improving the oil-gas separation effect of the oil-gas separation mechanism. Furthermore, even if the camshaft rotates relative to the exhaust pipe, causing wear on the sealing part, the small distance the sealing part moves towards the buffer groove during installation allows it to rebound after wear, ensuring it remains tightly against the exhaust passage wall and maintaining a tight seal.

[0009] In the aforementioned oil-gas separation mechanism for a motorcycle engine, the buffer groove has a V-shaped cross-section, and the circumferential edge of the sealing part protrudes beyond the circumferential edge of the main body. The V-shaped cross-section of the buffer groove allows the sealing part to better elastically deform towards the buffer groove, and the longer length of the sealing part increases the sealing area between the sealing part and the camshaft, thereby improving sealing performance.

[0010] In the aforementioned oil-gas separation mechanism for a motorcycle engine, the exhaust passage wall has an annular stepped surface, which is perpendicular to the axial direction of the exhaust passage. The circumferential edge of the sealing part abuts against the stepped surface. This structure prevents the exhaust gas after oil-gas separation from directly impacting the circumferential edge of the sealing part, thus preventing the sealing part from being blown open and ensuring its sealing performance.

[0011] In the aforementioned oil-gas separation mechanism for a motorcycle engine, the exhaust pipe includes an annularly protruding abutment portion on its circumferential outer wall. The outer diameter of the abutment portion is smaller than the diameter of the mounting hole, and the main body abuts against the abutment portion. The abutment portion acts as abutment against a sealing element, limiting the position of the sealing element. The abutment portion causes the sealing element to elastically deform, pressing its circumferential edge tightly against the channel wall of the exhaust passage.

[0012] In the aforementioned oil-gas separation mechanism for a motorcycle engine, the exhaust passage is flared at the end near the exhaust pipe, and both the seal and the abutment are integrally located within the exhaust passage. The seal and abutment are located within the camshaft, which reduces the corrosive interference of oil and gas on the seal, improving its service life and sealing performance.

[0013] In the aforementioned oil-gas separation mechanism for a motorcycle engine, the outer edge of the mounting hole has a first annular calibration surface. The exhaust pipe includes a calibration part that protrudes annularly on its outer circumferential wall. The calibration part abuts against the first calibration surface, causing the central axis of the exhaust passage and the central axis of the exhaust pipe to overlap. By having the calibration part abut against the first calibration surface, the central axis of the exhaust passage and the central axis of the exhaust pipe overlap, meaning the camshaft and the exhaust pipe are coaxially arranged. This ensures that the force pressing the circumferential edge of the sealing part against the stepped surface is balanced, guaranteeing sealing performance. Furthermore, it ensures that the wear on each edge of the sealing part is consistent, further guaranteeing sealing performance.

[0014] In the aforementioned oil-gas separation mechanism for a motorcycle engine, the calibration section has a second calibration surface in the shape of a cone, and the first calibration surface has an arc-shaped cross-section. The second calibration surface abuts against the first calibration surface. This structure improves the fit between the second and first calibration surfaces, enhances calibration, ensures the coaxial arrangement of the camshaft and exhaust pipe, and improves the sealing performance of the sealing section.

[0015] In the aforementioned oil-gas separation mechanism for a motorcycle engine, the mechanism further includes fasteners and a pressure plate. The bottom of the pressure plate has a clearance hole through which the outer end of the exhaust pipe passes. The pressure plate is fixedly connected to the housing by the fasteners. The pressure plate presses the calibration part against the first calibration surface, thereby axially positioning the exhaust pipe and the housing. By pressing the calibration part against the first calibration surface with the pressure plate, the exhaust pipe and the housing are axially positioned, allowing the seal to move into place and ensuring proper sealing, thus facilitating installation.

[0016] In the aforementioned oil-gas separation mechanism for a motorcycle engine, the exhaust pipe includes a pair of annular protrusions on its circumferential outer wall. The outer diameter of the protrusions is smaller than the diameter of the mounting hole. Both protrusions are located within the mounting hole, and a sealing ring for sealing the housing and the exhaust pipe is fitted between the pair of protrusions. The smaller outer diameter of the protrusions allows the exhaust pipe to pass through the mounting hole without affecting its installation, prevents contact between the protrusions and the housing, and ensures the coaxiality of the camshaft and the exhaust pipe, thus guaranteeing the sealing performance of the seal.

[0017] Compared with the prior art, the oil-gas separation mechanism for a motorcycle engine provided by the present invention has the following advantages:

[0018] 1. This oil-gas separation mechanism moves the exhaust pipe to push the sealing element into the exhaust channel, and the exhaust pipe also presses the circumferential edge of the sealing part against the channel wall of the exhaust channel to form a seal, so that the mixed gas in the housing cannot enter the exhaust channel through the gap, thereby improving the oil-gas separation effect of the oil-gas separation mechanism.

[0019] 2. The cross-section of the buffer groove in the seal of this oil-gas separation mechanism is V-shaped, and the length of the sealing part is relatively long, so that the sealing part can fit more tightly against the camshaft, increasing the sealing area and improving the sealing performance. This prevents the mixed gas in the housing from entering the exhaust channel through the gap, thereby improving the oil-gas separation effect of the oil-gas separation mechanism. Even if the camshaft rotates and wears the sealing part, the rebound of the sealing part can ensure the sealing performance.

[0020] 3. This oil-gas separation mechanism, through the cooperation of the second calibration surface and the first calibration surface, ensures that the camshaft and exhaust pipe are set coaxially, thereby improving the sealing performance of the sealing part. Attached Figure Description

[0021] Figure 1 This is a cross-sectional view of the overall structure of this oil-gas separation mechanism.

[0022] Figure 2 This is a cross-sectional view of the exhaust pipe and seals of this oil-gas separation mechanism.

[0023] Figure 3 This is an exploded view of the exhaust pipe, seals, and sealing rings of this oil-gas separation mechanism.

[0024] Figure 4 This is an oil-gas separation mechanism Figure 2 Enlarged view of area A.

[0025] Figure 5 This is an enlarged view of the pressure plate of the oil-gas separation mechanism.

[0026] In the figure, 1. Housing; 11. Mounting hole; 12. First calibration surface; 2. Camshaft; 21. Exhaust passage; 22. Stepped surface; 3. Exhaust pipe; 31. Abutment part; 32. Calibration part; 321. Second calibration surface; 33. Protruding edge; 4. Seal; 41. Sealing part; 42. Main body; 43. Buffer groove; 5. Fastener; 6. Pressure plate; 61. Clearance hole; 7. Sealing ring. Detailed Implementation

[0027] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0028] like Figure 1 As shown, the motorcycle engine includes a housing 1 and an oil-gas separation mechanism. The oil-gas separation mechanism includes a camshaft 2, an exhaust pipe 3, a seal 4, a fastener 5, a pressure plate 6, and a sealing ring 7. The camshaft 2 is rotatably mounted in the housing 1 and has an exhaust passage 21. The housing 1 has a mounting hole 11.

[0029] like Figure 2 , Figure 3 As shown, the circumferential outer wall of the exhaust pipe 3 has an abutment portion 31, a pair of protruding edges 33, and a calibration portion 32. The abutment portion 31, the pair of protruding edges 33, and the calibration portion 32 are all annularly protruding, with the pair of protruding edges 33 located between the abutment portion 31 and the calibration portion 32. The outer diameters of the abutment portion 31 and the protruding edges 33 are both smaller than the diameter of the mounting hole 11, while the outer diameter of the calibration portion 32 is larger than the diameter of the mounting hole 11.

[0030] The sealing element 4 includes a sealing part 41 and a main body 42, both of which are annular. The sealing part 41 is located on one side of the main body 42. The sealing part 41 and the main body 42 are an integral structure. The sealing part 41 is elastic. There is an annular buffer groove 43 on the outer circumferential direction between the sealing part 41 and the main body 42. The cross-section of the buffer groove 43 is V-shaped. The sealing part 41 is inclined outward along the direction of the main body 42 toward the sealing part 41. The circumferential edge of the sealing part 41 protrudes outward from the circumferential edge of the main body 42.

[0031] The sealing element 4 is fitted over the exhaust pipe 3, and the main body 42 abuts against the abutment part 31. The exhaust passage 21 is flared at the end near the exhaust pipe 3. The exhaust pipe 3 passes through the mounting hole 11 and is axially positioned with the housing 1. A pair of protruding edges 33 are located in the mounting hole 11, and the sealing ring 7 is located between the pair of protruding edges 33. The sealing ring 7 seals the gap between the exhaust pipe 3 and the housing 1. The sealing element 4 and the abutment part 31 are both integrally inserted into one end of the exhaust passage 21. The passage wall at one end of the exhaust passage 21 has an annular stepped surface 22, which is perpendicular to the axial direction of the exhaust passage 21. The exhaust pipe 3 presses the edge of the sealing part 41 tightly against the stepped surface 22.

[0032] like Figure 4 As shown, the outer edge of the mounting hole 11 has a first annular calibration surface 12, the cross-section of which is arc-shaped, and the calibration part 32 has a second calibration surface 321 that is conical. Figure 5 As shown, the bottom of the pressure plate 6 has a clearance hole 61, the outer end of the exhaust pipe 3 passes through the clearance hole 61, the pressure plate 6 is fixed to the housing 1 by fasteners 5 such as bolts, the pressure plate 6 pushes the calibration part 32 so that the second calibration surface 321 abuts against the first calibration surface 12, so that the exhaust pipe 3 is axially positioned with the housing 1, and the central axis of the exhaust channel 21 and the central axis of the exhaust pipe 3 overlap.

[0033] During installation, the sealing element 4 is fitted over the exhaust pipe 3. The exhaust pipe 3 passes through the mounting hole 11 until the calibration part 32 abuts against the housing 1. Then, the pressure plate 6 is placed and locked. The pressure plate 6 pushes the calibration part 32 so that the second calibration surface 321 abuts against the first calibration surface 12, so that the exhaust pipe 3 is installed in place and the sealing element 4 is installed in place. The circumferential edge of the sealing part 41 is pressed against the channel wall of the exhaust channel 21 to form a seal.

[0034] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

[0035] Although this document frequently uses terms such as housing 1, mounting hole 11, first calibration surface 12, camshaft 2, exhaust passage 21, stepped surface 22, exhaust pipe 3, abutment 31, calibration part 32, second calibration surface 321, raised edge 33, seal 4, sealing part 41, main body 42, buffer groove 43, fastener 5, pressure plate 6, clearance hole 61, and sealing ring 7, the possibility of using other terms is not excluded. These terms are used merely for the convenience of describing and explaining the essence of the invention; interpreting them as any additional limitation would contradict the spirit of the invention.

Claims

1. An oil-gas separation mechanism for a motorcycle engine, the engine including a housing (1), the oil-gas separation mechanism including a camshaft (2) located in the housing (1) and having an exhaust passage (21), characterized in that, The oil-gas separation mechanism also includes an exhaust pipe (3) and a sealing element (4) fitted over the exhaust pipe (3). The sealing element (4) includes a ring-shaped, protruding, and elastic sealing portion (41). The housing (1) has a mounting hole (11). The exhaust pipe (3) passes through the mounting hole (11) and is axially positioned with the housing (1). The sealing element (4) extends into the exhaust channel (21). The exhaust pipe (3) presses the circumferential edge of the sealing portion (41) against the channel wall of the exhaust channel (21). The sealing element (4) also includes a ring-shaped body (42). The sealing portion (41) is located on one side of the body (42). 1) There is an annular buffer groove (43) on the outer circumferential side between the main body (42) and the main body (42). The sealing part (41) is inclined outward along the direction of the main body (42) toward the sealing part (41). The channel wall of the exhaust channel (21) has an annular stepped surface (22). The stepped surface (22) is perpendicular to the axial direction of the exhaust channel (21). The circumferential edge of the sealing part (41) abuts against the stepped surface (22). The exhaust pipe (3) includes an annular protruding abutment part (31) on the outer circumferential side wall. The outer diameter of the abutment part (31) is smaller than the diameter of the mounting hole (11). The main body (42) abuts against the abutment part (31).

2. The oil-gas separation mechanism for a motorcycle engine according to claim 1, characterized in that, The buffer groove (43) has a V-shaped cross-section, and the circumferential edge of the sealing part (41) protrudes out from the circumferential edge of the main body (42).

3. The oil-gas separation mechanism for a motorcycle engine according to claim 1 or 2, characterized in that, The exhaust passage (21) is flared at one end near the exhaust pipe (3), and the seal (4) and the abutment (31) are both located in the exhaust passage (21).

4. The oil-gas separation mechanism for a motorcycle engine according to claim 1 or 2, characterized in that, The mounting hole (11) has a first calibration surface (12) in the shape of an annular shape at the circumferential edge of the outer opening. The exhaust pipe (3) includes a calibration part (32) in the shape of an annular protrusion on the circumferential outer wall. The calibration part (32) abuts against the first calibration surface (12) so that the central axis of the exhaust channel (21) and the central axis of the exhaust pipe (3) overlap.

5. The oil-gas separation mechanism for a motorcycle engine according to claim 4, characterized in that, The calibration section (32) has a second calibration surface (321) in the shape of a cone, the cross-section of the first calibration surface (12) is arc-shaped, and the second calibration surface (321) abuts against the first calibration surface (12).

6. The oil-gas separation mechanism for a motorcycle engine according to claim 4, characterized in that, The oil-gas separation mechanism also includes fasteners (5) and pressure plates (6). The bottom of the pressure plate (6) has a clearance hole (61). The outer end of the exhaust pipe (3) passes through the clearance hole (61). The pressure plate (6) is fixed to the housing (1) by the fasteners (5). The pressure plate (6) presses the calibration part (32) onto the first calibration surface (12) to make the exhaust pipe (3) axially positioned with respect to the housing (1).

7. The oil-gas separation mechanism for a motorcycle engine according to claim 1 or 2, characterized in that, The exhaust pipe (3) includes a pair of protruding edges (33) on the circumferential outer wall. The outer diameter of the protruding edges (33) is smaller than the diameter of the mounting hole (11). Both of the protruding edges (33) are located in the mounting hole (11). A sealing ring (7) for sealing the housing (1) and the exhaust pipe (3) is sleeved between the pair of protruding edges (33).

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