Low-engine-oil-consumption piston two-ring structure of diesel engine

Abstract

The low-engine-oil-consumption piston two-ring structure of the diesel engine comprises a ring body, the ring body is in a hollow column shape, the ring body is provided with a strip-shaped piston ring closed opening in the axial direction, the top of the inner wall of the ring body is provided with an upper chamfered face, the lower bottom of the inner wall of the ring body is provided with a lower chamfered face, and the top of the outer wall of the ring body is provided with a top conical angle. A nose-shaped groove is formed in the bottom of the outer wall of the ring body; and a Cr coating is coated on the outer wall of the ring body between the top conical angle and the nose-shaped groove. According to the low-engine-oil-consumption piston two-ring structure of the diesel engine, the problem that the oil scraping capacity of the oil scraping blade of the piston ring is weak under the low-load working condition of the engine is solved, the defect that in the prior art, the engine oil consumption is increased to one thousandth and exceeds 0.5 thousandth is overcome, and meanwhile the service life standard requirement of a piston two-ring is met.

Description

Technical Field

[0001] This utility model belongs to the field of diesel engine technology, specifically relating to a low-oil-consumption piston two-ring structure for diesel engines. Background Technology

[0002] Diesel engine pistons typically have three piston rings. Because the first compression ring has poor lubrication in its working area, it is usually a steel barrel-faced ring used for oil distribution and sealing, preventing excessive wear. The second ring is designed as a rectangular tapered ring to scrape oil from the cylinder liner walls; it is made of steel or cast iron. The oil ring is designed with evenly distributed drain holes and two very narrow scraping edges to scrape oil from the cylinder walls and ensure timely return of scraped oil to the oil pan; it is made of steel. Due to increasing engine manufacturing costs and rising customer expectations for engine lifespan, wear-resistant coatings are widely used on engine moving parts to balance these demands. The current mainstream piston ring outer circumference coating strategy is a DLC coating for the first ring, a PVD coating for the second ring, and a PVD coating for the oil ring. These coatings significantly extend the lifespan of the piston rings.

[0003] Due to the PVD coating process required for the outer surface of the second ring, a 0.2mm bevel angle oil scraping blade is formed on the outer surface and lower side of the finished second ring. As a result of the bevel angle, the oil scraping blade is no longer sharp, the oil scraping ability of the second ring is weakened, and the oil that is not scraped clean remains on the cylinder liner wall and is burned. Under low engine load conditions, this leads to an increase in oil consumption of 1‰, exceeding the standard requirement of 0.5‰. Utility Model Content

[0004] The purpose of this invention is to provide a low-oil-consumption piston two-ring structure for diesel engines, which solves the problem of weak oil scraping ability of piston ring scraping blades under low-load engine conditions.

[0005] The technical solution adopted by this utility model is a low oil consumption piston two-ring structure for diesel engines, including a ring body, which is a hollow column shape. The ring body has a strip-shaped piston ring closed opening along the axial direction. The top of the inner wall of the ring body has an upper chamfered surface, the bottom of the inner wall of the ring body has a lower chamfered surface, the top of the outer wall of the ring body has a top conical angle, the bottom of the outer wall of the ring body has a nose-shaped groove, and a Cr coating is applied to the outer wall of the ring body between the top conical angle and the nose-shaped groove.

[0006] The features of this utility model also include:

[0007] The outer diameter of the ring is 120 mm, the ring thickness is 4.2 mm, and the ring height is 2.5 mm.

[0008] The inner diameter runout of the ring is 0.15 mm, and the straightness of the bottom end of the ring is 0.003 mm.

[0009] The closing gap of the strip piston ring is 0.5-0.7mm.

[0010] The dimensions of both the upper and lower chamfered surfaces are 0.2 × 45°.

[0011] The angle of the top cone is 2.5°±0°30′.

[0012] The radial dimension of the nose-shaped groove is 0.4-0.8 mm, the axial dimension of the nose-shaped groove is 0.3-0.7 mm, the nose-shaped groove is opened along the ring body from the bottom outer wall to the top inner wall, and the inner included angle of the nose-shaped groove is 75°±0.5°.

[0013] The Cr coating thickness is 0.05 mm.

[0014] The beneficial effects of this utility model are:

[0015] The low oil consumption piston ring structure for diesel engines provided by this utility model solves the problem of weak oil scraping ability of piston ring scraping blades under low engine load conditions, makes up for the defects of existing technology where oil consumption increases to 1‰, exceeding 0.5‰, and at the same time meets the piston ring life specification requirements. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the low-oil-consumption piston two-ring structure of this utility model for diesel engines;

[0017] Figure 2 This is a schematic diagram of the AA cross-section of this utility model.

[0018] In the figure, 1. Ring body, 2. Closed strip piston ring, 3. Upper chamfered surface, 4. Lower chamfered surface, 5. Top conical angle, 6. Nose-shaped groove, 7. Cr coating. Detailed Implementation

[0019] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0020] The diesel engine low-oil-consumption piston two-ring structure provided by this utility model, such as Figure 1 As shown, it includes a ring body 1, which is a hollow column shape. The ring body 1 has a strip-shaped piston ring opening 2 along its axial direction. The elastic force of the strip-shaped piston ring opening 2 is 20-30N. Figure 2As shown, the inner wall of ring 1 has an upper chamfered surface 3 at the top and a lower chamfered surface 4 at the bottom. The outer wall of ring 1 has a top conical angle 5 at the top and a nose-shaped groove 6 at the bottom, forming a very sharp oil scraping blade. A Cr coating 7 is applied to the outer wall of ring 1 between the top conical angle 5 and the nose-shaped groove 6. The outer diameter of ring 1 is 120mm, the ring thickness is 4.2mm, and the ring height is 2.5mm. The inner diameter runout of ring 1 is 0.15mm, and the straightness of the bottom end of ring 1 is 0.003mm. The closing gap of the strip piston ring closure 2 is 0.5-0.7mm. The upper chamfered surface 4 is also present. The dimensions of the corner face 3 and the lower chamfer face 4 are both 0.2×45°; the angle of the top cone angle 5 is 2.5°±0°30′; the radial dimension of the nose-shaped groove 6 is 0.4-0.8mm, the axial dimension of the nose-shaped groove 6 is 0.3-0.7mm, the nose-shaped groove 6 is opened along the ring body 1 from the bottom outer wall to the top inner wall, and the inner included angle of the nose-shaped groove 6 is 75°±0.5°; the thickness of the Cr coating 7 is 0.05mm; this solves the problem of weak oil scraping ability of the piston ring oil scraping edge under low engine load conditions, makes up for the defect of increased oil consumption of 1‰ in the existing technology, exceeding 0.5‰, and meets the piston ring life specification requirements.

[0021] The diesel engine low oil consumption piston two-ring structure provided by this utility model works as follows: the existing piston ring is a conventionally designed rectangular conical ring with a full PVD coating on the outer surface. The PVD coating has the characteristics of high wear resistance, strong anti-galling, and long service life. The outer surface of the piston is fully coated. Due to the requirements of the coating manufacturing process, the outer surface and lower side of the piston ring will form a 0.2mm conical oil scraping edge. Ideally, the oil scraping edge is a very sharp edge without rounded corners. Such a sharp edge is very beneficial for oil scraping. Although the original piston ring oil scraping edge is already very small, when scraping oil downwards, a small amount of oil will still remain in the cylinder liner and be consumed by combustion. In this application, the outer surface of the piston ring body 1 is partially inlaid with a Cr coating, and a nose-shaped groove is machined on the lower side and outer surface. This will form a very sharp oil scraping edge, with a cutting edge angle usually less than 0.05mm, which is very beneficial for the piston ring to scrape oil downwards. However, the outer surface of the piston ring in the prior art is fully coated with PVD, and the coating is very hard. Because the coating is easily damaged during machining, the outer surface of the ring is usually not machined, and only the lower side of the ring is machined. As a result, the oil scraping edge angle of the ring is usually 0.2mm, which is not conducive to oil scraping. After engine testing, the piston rings of this application meet the durability requirements. The wear of the rings after the durability test is close to that of existing piston rings. Under the same working conditions, the oil consumption of the piston rings of this application is reduced from 1‰ to 0.35‰, meeting the standard requirement of 0.5‰.

[0022] Example 1

[0023] The diesel engine low-oil-consumption piston two-ring structure proposed in this embodiment, such as... Figure 1 As shown, it includes a ring body 1, which is a hollow column shape. The ring body 1 has a strip-shaped piston ring opening 2 along its axial direction, as shown in the figure. Figure 2 As shown, the inner wall of ring 1 has an upper chamfered surface 3 at the top and a lower chamfered surface 4 at the bottom. The outer wall of ring 1 has a top conical angle 5 at the top and a nose-shaped groove 6 at the bottom. A Cr coating 7 is applied to the outer wall of ring 1 between the top conical angle 5 and the nose-shaped groove 6. Under low engine load conditions, the piston ring scraper has strong oil scraping ability, with oil consumption of 0.35‰, less than 0.5‰, while meeting the piston ring life specification requirements.

[0024] Example 2

[0025] The diesel engine low-oil-consumption piston two-ring structure proposed in this embodiment, such as... Figure 1 As shown, it includes a ring body 1, which is a hollow column shape. The ring body 1 has a strip-shaped piston ring opening 2 along its axial direction, as shown in the figure. Figure 2 As shown, the top of the inner wall of the ring 1 is provided with an upper chamfered surface 3, the bottom of the inner wall of the ring 1 is provided with a lower chamfered surface 4, the top of the outer wall of the ring 1 is provided with a top conical angle 5, the bottom of the outer wall of the ring 1 is provided with a nose-shaped groove 6, and a Cr coating 7 is applied to the outer wall of the ring 1 between the top conical angle 5 and the nose-shaped groove 6.

[0026] The outer diameter of ring 1 is 120mm, the ring thickness is 4.2mm, and the ring height is 2.5mm. Under low engine load conditions, the piston ring scraper has a strong oil scraping ability, with an oil consumption of 0.35‰, less than 0.5‰, while meeting the piston ring life specification requirements.

[0027] Example 3

[0028] The diesel engine low-oil-consumption piston two-ring structure proposed in this embodiment, such as... Figure 1 As shown, it includes a ring body 1, which is a hollow column shape. The ring body 1 has a strip-shaped piston ring opening 2 along its axial direction, as shown in the figure. Figure 2 As shown, the top of the inner wall of the ring 1 is provided with an upper chamfered surface 3, the bottom of the inner wall of the ring 1 is provided with a lower chamfered surface 4, the top of the outer wall of the ring 1 is provided with a top conical angle 5, the bottom of the outer wall of the ring 1 is provided with a nose-shaped groove 6, and a Cr coating 7 is applied to the outer wall of the ring 1 between the top conical angle 5 and the nose-shaped groove 6.

[0029] The outer diameter of ring 1 is 120mm, the thickness of ring 1 is 4.2mm, and the height of ring 1 is 2.5mm.

[0030] The inner diameter runout of ring 1 is 0.15mm, and the straightness of the bottom end of ring 1 is 0.003mm. Under low engine load conditions, the piston ring scraper has a strong oil scraping ability, and the oil consumption is 0.35‰, which is less than 0.5‰, while meeting the piston ring life specification requirements.

[0031] Example 4

[0032] The diesel engine low-oil-consumption piston two-ring structure proposed in this embodiment, such as... Figure 1 As shown, it includes a ring body 1, which is a hollow column shape. The ring body 1 has a strip-shaped piston ring opening 2 along its axial direction, as shown in the figure. Figure 2 As shown, the top of the inner wall of the ring 1 is provided with an upper chamfered surface 3, the bottom of the inner wall of the ring 1 is provided with a lower chamfered surface 4, the top of the outer wall of the ring 1 is provided with a top conical angle 5, the bottom of the outer wall of the ring 1 is provided with a nose-shaped groove 6, and a Cr coating 7 is applied to the outer wall of the ring 1 between the top conical angle 5 and the nose-shaped groove 6.

[0033] The outer diameter of ring 1 is 120mm, the thickness of ring 1 is 4.2mm, and the height of ring 1 is 2.5mm.

[0034] The inner diameter runout of ring 1 is 0.15 mm, and the straightness of the bottom end of ring 1 is 0.003 mm;

[0035] The closing gap of the strip piston ring closure 2 is 0.5-0.7mm. Under low engine load conditions, the piston ring oil scraping edge has a strong oil scraping ability, and the oil consumption is 0.35‰, less than 0.5‰, while meeting the piston ring life specification requirements.

[0036] Example 5

[0037] The diesel engine low-oil-consumption piston two-ring structure proposed in this embodiment, such as... Figure 1 As shown, it includes a ring body 1, which is a hollow column shape. The ring body 1 has a strip-shaped piston ring opening 2 along its axial direction, as shown in the figure. Figure 2 As shown, the top of the inner wall of the ring 1 is provided with an upper chamfered surface 3, the bottom of the inner wall of the ring 1 is provided with a lower chamfered surface 4, the top of the outer wall of the ring 1 is provided with a top conical angle 5, the bottom of the outer wall of the ring 1 is provided with a nose-shaped groove 6, and a Cr coating 7 is applied to the outer wall of the ring 1 between the top conical angle 5 and the nose-shaped groove 6.

[0038] The outer diameter of ring 1 is 120mm, the thickness of ring 1 is 4.2mm, and the height of ring 1 is 2.5mm.

[0039] The inner diameter runout of ring 1 is 0.15 mm, and the straightness of the bottom end of ring 1 is 0.003 mm;

[0040] The closing gap of the closed section 2 of the strip piston ring is 0.5-0.7mm;

[0041] Both the upper chamfered surface 3 and the lower chamfered surface 4 have dimensions of 0.2×45°. Under low engine load conditions, the piston ring oil scraping edge has a strong oil scraping ability, with oil consumption of 0.35‰, less than 0.5‰, while meeting the piston ring life specification requirements.

[0042] Example 6

[0043] The diesel engine low-oil-consumption piston two-ring structure proposed in this embodiment, such as... Figure 1 As shown, it includes a ring body 1, which is a hollow column shape. The ring body 1 has a strip-shaped piston ring opening 2 along its axial direction, as shown in the figure. Figure 2 As shown, the top of the inner wall of the ring 1 is provided with an upper chamfered surface 3, the bottom of the inner wall of the ring 1 is provided with a lower chamfered surface 4, the top of the outer wall of the ring 1 is provided with a top conical angle 5, the bottom of the outer wall of the ring 1 is provided with a nose-shaped groove 6, and a Cr coating 7 is applied to the outer wall of the ring 1 between the top conical angle 5 and the nose-shaped groove 6.

[0044] The outer diameter of ring 1 is 120mm, the thickness of ring 1 is 4.2mm, and the height of ring 1 is 2.5mm.

[0045] The inner diameter runout of ring 1 is 0.15 mm, and the straightness of the bottom end of ring 1 is 0.003 mm;

[0046] The closing gap of the closed section 2 of the strip piston ring is 0.5-0.7mm;

[0047] The dimensions of both the upper chamfered surface 3 and the lower chamfered surface 4 are 0.2 × 45°;

[0048] The top cone angle 5 is 2.5°±0°30′. Under low engine load conditions, the piston ring oil scraping edge has a strong oil scraping ability, and the oil consumption is 0.35‰, which is less than 0.5‰, while meeting the piston ring life specification requirements.

[0049] Example 7

[0050] The diesel engine low-oil-consumption piston two-ring structure proposed in this embodiment, such as... Figure 1 As shown, it includes a ring body 1, which is a hollow column shape. The ring body 1 has a strip-shaped piston ring opening 2 along its axial direction, as shown in the figure. Figure 2 As shown, the top of the inner wall of the ring 1 is provided with an upper chamfered surface 3, the bottom of the inner wall of the ring 1 is provided with a lower chamfered surface 4, the top of the outer wall of the ring 1 is provided with a top conical angle 5, the bottom of the outer wall of the ring 1 is provided with a nose-shaped groove 6, and a Cr coating 7 is applied to the outer wall of the ring 1 between the top conical angle 5 and the nose-shaped groove 6.

[0051] The outer diameter of ring 1 is 120mm, the thickness of ring 1 is 4.2mm, and the height of ring 1 is 2.5mm.

[0052] The inner diameter runout of ring 1 is 0.15 mm, and the straightness of the bottom end of ring 1 is 0.003 mm;

[0053] The closing gap of the closed section 2 of the strip piston ring is 0.5-0.7mm;

[0054] The dimensions of both the upper chamfered surface 3 and the lower chamfered surface 4 are 0.2 × 45°;

[0055] The angle of the top cone angle 5 is 2.5°±0°30′;

[0056] The radial dimension of the nose-shaped groove 6 is 0.4-0.8 mm, and the axial dimension is 0.3-0.7 mm. The nose-shaped groove 6 is formed along the ring body 1 from the bottom outer wall to the top inner wall, and the inner included angle of the nose-shaped groove 6 is 75°±0.5°. Under low engine load conditions, the piston ring oil scraping edge has a strong oil scraping ability, and the oil consumption is 0.35‰, less than 0.5‰, while meeting the piston ring life specification requirements.

[0057] Example 8

[0058] The diesel engine low-oil-consumption piston two-ring structure proposed in this embodiment, such as... Figure 1 As shown, it includes a ring body 1, which is a hollow column shape. The ring body 1 has a strip-shaped piston ring opening 2 along its axial direction, as shown in the figure. Figure 2 As shown, the top of the inner wall of the ring 1 is provided with an upper chamfered surface 3, the bottom of the inner wall of the ring 1 is provided with a lower chamfered surface 4, the top of the outer wall of the ring 1 is provided with a top conical angle 5, the bottom of the outer wall of the ring 1 is provided with a nose-shaped groove 6, and a Cr coating 7 is applied to the outer wall of the ring 1 between the top conical angle 5 and the nose-shaped groove 6.

[0059] The outer diameter of ring 1 is 120mm, the thickness of ring 1 is 4.2mm, and the height of ring 1 is 2.5mm.

[0060] The inner diameter runout of ring 1 is 0.15 mm, and the straightness of the bottom end of ring 1 is 0.003 mm;

[0061] The closing gap of the closed section 2 of the strip piston ring is 0.5-0.7mm;

[0062] The dimensions of both the upper chamfered surface 3 and the lower chamfered surface 4 are 0.2 × 45°;

[0063] The angle of the top cone angle 5 is 2.5°±0°30′;

[0064] The radial dimension of the nose-shaped groove 6 is 0.4-0.8mm, the axial dimension of the nose-shaped groove 6 is 0.3-0.7mm, the nose-shaped groove 6 is opened along the ring body 1 from the bottom outer wall to the top inner direction, and the inner included angle of the nose-shaped groove 6 is 75°±0.5°.

[0065] The Cr coating thickness is 0.05mm. Under low engine load conditions, the piston ring scraper has strong oil scraping ability, with oil consumption of 0.35‰, less than 0.5‰, while meeting the piston ring life specifications.

Claims

1. A two-ring configuration for low oil consumption pistons for diesel engines, characterized in that, The application relates to a piston ring, which comprises a ring body (1) in a hollow columnar shape, a strip-shaped piston ring closed opening (2) is arranged on the ring body (1) in an axial direction, an upper chamfer surface (3) is arranged on the top inner wall of the ring body (1), a lower chamfer surface (4) is arranged on the lower bottom inner wall of the ring body (1), a top conical angle (5) is arranged on the top outer wall of the ring body (1), a nose-shaped groove (6) is arranged on the bottom outer wall of the ring body (1), and a Cr coating (7) is coated on the outer wall of the ring body (1) between the top conical angle (5) and the nose-shaped groove (6).

2. The low oil consumption diesel engine piston two ring design of claim 1 wherein, The outer diameter of the ring body (1) is 120 mm, the ring thickness of the ring body (1) is 4.2 mm, and the ring height of the ring body (1) is 2.5 mm.

3. The low oil consumption diesel engine piston two ring design of claim 1 wherein, The inner diameter runout of the ring body (1) is 0.15 mm, and the straightness of the bottom end of the ring body (1) is 0.003 mm.

4. The low oil consumption diesel engine piston two ring design of claim 1 wherein, The closed opening gap of the strip-shaped piston ring closed opening (2) is 0.5-0.7 mm.

5. The low oil consumption diesel engine piston two ring design of claim 1 wherein, The sizes of the upper chamfer surface (3) and the lower chamfer surface (4) are both 0.2*45 DEG.

6. The low oil consumption diesel engine piston two ring design of claim 1 wherein, The angle of the top conical angle (5) is 2.5 DEG+ / -0*30'.

7. The low oil consumption diesel engine piston two ring design of claim 1 wherein, The radial size of the nose-shaped groove (6) is 0.4-0.8 mm, the axial size of the nose-shaped groove (6) is 0.3-0.7 mm, the nose-shaped groove (6) is arranged on the ring body (1) from the bottom outer wall to the top inner wall in a direction, and the inner included angle of the nose-shaped groove (6) is 75 DEG+ / -0.5 DEG.

8. The low oil consumption diesel engine piston two ring design of claim 1 wherein, The thickness of the Cr coating (7) is 0.05 mm.

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