A piston ring set for reducing blow-by and oil consumption of a hydrogen combustion engine

Abstract

The utility model discloses a piston ring set of reducing hydrogen burning engine blowby and oil consumption, including the top ring and oil scraper ring of adapting to hydrogen burning engine, the top ring includes ring body and wiper, and the lower end surface of ring body is equipped with the first recess that penetrates along the circumference, and it extends from the outer edge of ring body to the inside, and ring body and wiper are equipped with the first opening and second opening that penetrate respectively in radial and axial, and the staggered angle alpha of two openings on circumference satisfies 90 DEG <= alpha <= 180 DEG, the oil scraper ring is the nose type integral structure, and its lower end surface is equipped with the second recess that penetrates along the circumference, and it extends from the outer edge of oil scraper ring to the inside, and its groove bottom is inclined to the outer edge of oil scraper ring downward, and the included angle beta of the groove bottom of second recess and vertical side wall satisfies 75 DEG <= beta < 90 DEG, and the upper part of corresponding second recess is convex and forms the nose, and its outer circular surface is the taper surface, and it is inclined to the center direction of oil scraper ring from the groove bottom of second recess, and the inclination angle gamma satisfies 1 DEG <= gamma <= 2 DEG, and the inside lower end of oil scraper ring is equipped with the chamfer gap along the circumference.

Description

Technical Field

[0001] This utility model relates to the field of hydrogen fuel cell engine technology, and in particular to a piston ring assembly for reducing blow-by and oil consumption in hydrogen fuel cell engines. Background Technology

[0002] Hydrogen combustion engines, as key equipment in the field of new energy power, have become a core research and development direction for industries such as automobiles and construction machinery due to the advantages of zero carbon emissions and high energy density from hydrogen combustion. Piston ring assemblies, as a crucial barrier between the engine cylinder and crankcase, bear the dual core functions of gas sealing and oil control. The top ring needs to efficiently block hydrogen gas leakage from the combustion chamber to prevent gas contamination of the oil and reduction of engine efficiency; the oil scraper ring needs to precisely scrape excess oil from the cylinder wall to prevent oil from entering the combustion chamber and contributing to carbon deposits, while ensuring a uniform oil film on the cylinder wall to reduce friction loss. However, the inherent characteristics of hydrogen gas molecules—small size and high permeability—combined with the high-frequency reciprocating, high-temperature, and high-pressure operating conditions of hydrogen combustion engines, place stringent requirements on the "sealing-oil scraping" synergy of the piston ring assembly, making traditional piston ring assemblies inadequate.

[0003] Existing piston ring designs with a combination of top ring and oil scraper ring generally suffer from a lack of synergy. Top rings often employ a single-opening structure or double-opening designs that are not properly staggered, allowing hydrogen fuel gas to leak rapidly from the openings, leading to reduced sealing efficiency. The large amount of leaked fuel gas directly impacts the oil scraper ring, forcing it to bear excessive sealing and oil scraping loads simultaneously. Furthermore, the groove structure and sealing surface morphology of the oil scraper ring are poorly adapted to the top ring. The depth and width ratio of the second groove are poorly designed, resulting in a narrow oil return channel prone to accumulation. The structure of the nose and cone surface is not optimized for fuel gas leakage scenarios, leading to decreased sealing performance during oil scraping. Moreover, fuel gas leakage further exacerbates oil oxidation and deterioration, creating a vicious cycle of "seal failure → surge in oil scraping load → increased oil consumption." These synergy deficiencies make existing piston ring assemblies insufficiently adaptable to the operating requirements of hydrogen-powered engines, impacting engine reliability and user experience.

[0004] The above background information is provided only to aid in understanding the concept and technical solution of this utility model. It does not necessarily belong to the prior art of this patent application. In the absence of clear evidence that the above information was disclosed on the filing date of this patent application, the above background information should not be used to evaluate the novelty and inventiveness of this application. Utility Model Content

[0005] The purpose of this invention is to propose a piston ring assembly that reduces blow-by and oil consumption in hydrogen fuel cell engines, thereby solving the technical problems of insufficient coordination between the top ring and the oil scraper ring, easy leakage of fuel gas from the opening, and obstruction of oil return in the prior art.

[0006] Therefore, this utility model proposes a piston ring assembly to reduce blow-by and oil consumption in hydrogen fuel cell engines.

[0007] Preferably, the present invention may also have the following technical features:

[0008] A piston ring assembly for reducing blow-by and oil consumption in a hydrogen fuel cell engine includes a top ring and an oil scraper ring adapted to the hydrogen fuel cell engine. The two rings are combined to form a structure through size adaptation and functional synergy, which is used to simultaneously achieve sealing and oil scraping.

[0009] The top ring includes a ring body and a scraper. The lower end face of the ring body is provided with a first groove that runs through the circumference. The first groove extends from the outer edge of the ring body inward. The first groove is used to embed the scraper, and the scraper can extend and retract radially along the first groove. The ring body and the scraper are respectively provided with a first opening and a second opening that both penetrate radially and axially. The first opening and the second opening are offset by an angle α on the circumference, which satisfies 90°≤α≤180°.

[0010] The oil scraper ring is a nose-shaped integrated structure. The lower end face of the oil scraper ring is provided with a second groove that runs through the circumference. The second groove extends inward from the outer edge of the oil scraper ring, and its bottom is inclined downward toward the outer edge of the oil scraper ring. The angle β between the bottom of the second groove and the vertical sidewall of the second groove satisfies 75°≤β<90°. A nose opening is formed by protrusions at the upper part of the second groove. The outer circular surface of the nose opening is a conical surface. The conical surface is inclined from the bottom of the second groove toward the center of the oil scraper ring, and its inclination angle γ satisfies 1°≤γ≤2°. The lower inner end of the oil scraper ring is provided with a chamfered notch along the circumference.

[0011] Preferably, the axial height of the top ring is H, the axial thickness of the oil scraper ring is D, and H and D satisfy 1.5D≤H≤2.5D.

[0012] Preferably, the vertical sidewall of the second groove and the bottom of the groove are smoothly transitioned by a circular arc, and the radius of the circular arc r1 satisfies 0.1mm≤r1≤0.3mm.

[0013] Preferably, the depth a of the second groove satisfies 14D≤a≤12D, and the groove width b satisfies 13D≤b≤35D.

[0014] Preferably, the axial height h of the nasal opening satisfies 1.2a≤h≤2a.

[0015] Preferably, the upper surface of the nasal opening is an arc-shaped surface, and the radius r2 of the arc-shaped surface satisfies 2D≤r2≤4D.

[0016] Preferably, the transition between the conical surface and the upper end face of the nose is provided with a rounded corner, and the radius of the rounded corner r3 satisfies 0.05mm≤r3≤0.15mm.

[0017] Preferably, the chamfer notch is a 45° right-angle chamfer, with a chamfer depth e satisfying 25D≤e≤35D and a chamfer width f satisfying 15D≤f≤12D.

[0018] Preferably, the surface roughness Ra of the bottom of the second groove is ≤0.8μm.

[0019] Preferably, the ring body and the oil scraper ring are both made of martensitic stainless steel or alloy cast iron, and the scraper blade is made of elastic alloy.

[0020] The beneficial effects of this utility model compared with the prior art include:

[0021] 1. The piston ring assembly of this utility model, consisting of a "combined top ring + nose-shaped oil scraper ring," forms a complete protection system through functional synergy. The top ring, with its double-opening staggered design, intercepts more than 80% of the combustion gases, while the radial extension and retraction characteristics of the scraper ensure a tight seal against the cylinder wall. The conical surface of the oil scraper ring receives residual combustion gases to form a secondary seal, and the inclined groove bottom and inner chamfer work together to construct an efficient oil guiding channel. The two simultaneously achieve "multi-stage combustion gas interception + directional oil return." Compared with traditional independent ring assemblies, blow-by volume is reduced, oil consumption is decreased, and the core pain points of hydrogen fuel cell engines are precisely addressed.

[0022] 2. The top ring scraper telescopic structure and the integrated structure of the oil scraper nose of this utility model complement each other. The elastic fitting characteristics of the top ring scraper compensate for the cylinder wall machining error and reduce the load on the oil scraper ring from the gas impact. The dimensional relationship between the height of the oil scraper nose and the depth of the second groove (nose height > groove depth) ensures that the conical surface sealing and the groove oil scraping function do not interfere with each other. Combined with the guiding effect of the inner chamfer, it avoids oil accumulation from affecting the sealing effect, so that the piston ring assembly maintains stable sealing and oil scraping performance during high-speed reciprocating motion, thus improving the reliability of operation.

[0023] 3. The combined structure of this utility model is optimized for the combustion characteristics of hydrogen engines. The staggered double opening design of the top ring extends the combustion leakage path and reduces the risk of hydrogen combustion corrosion to the ring assembly. The line contact characteristics between the oil scraper ring cone surface and the cylinder wall reduce friction loss, and the arc transition structure of the second groove avoids stress concentration. The two work together to share the workload and reduce excessive wear of a single component. With the selection of wear-resistant materials, the service life of the ring assembly is extended compared with traditional designs, making it suitable for the long-term high temperature and high pressure working environment of hydrogen engines. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the top ring structure according to a specific embodiment of the present invention.

[0025] Figure 2 This is a cross-sectional view of the top ring according to a specific embodiment of this utility model.

[0026] Figure 3This is a specific embodiment of the present utility model. Figure 2 Enlarged diagram of point A in the middle.

[0027] Figure 4 This is a cross-sectional view of the top ring according to a specific embodiment of this utility model.

[0028] Figure 5 This is a specific embodiment of the present utility model. Figure 4 Enlarged diagram of point B in the middle.

[0029] Explanation of reference numerals in the attached drawings: 1-top ring; 11-ring body; 111-first groove; 112-first opening; 113-first protrusion; 12-scraper; 121-second opening; 2-oil scraper ring; 21-second groove; 22-nose; 23-conical surface; 24-chamfered notch; 25-arc; 26-rounded corner. Detailed Implementation

[0030] The present invention will now be described in further detail with reference to specific embodiments and the accompanying drawings. It should be emphasized that the following description is merely exemplary and is not intended to limit the scope and application of the present invention.

[0031] Non-limiting and non-exclusive embodiments will be described with reference to the following figures, wherein the same reference numerals denote the same parts unless otherwise specifically stated.

[0032] This embodiment provides a piston ring assembly that reduces blow-by and oil consumption in a hydrogen fuel cell engine. The following is a description of the assembly in conjunction with the attached diagram. Figures 1-5 This application provides a further detailed description of its technical solution. This application and the "Piston Assembly with Combined Piston Rings and Unloading Groove Structure" submitted by the applicant on the same day are complementary technical solutions. The former's core innovation is the "piston ring land unloading groove + combined top ring," which uses the unloading groove to relieve the upward thrust of high-pressure gas on the top ring and the combined top ring to enhance sealing and fit. Together, they solve the problems of high-pressure top ring floating and increased sealing gap. This application focuses on the collaborative sealing and oil-scraping design of "combined top ring 1 + oil scraper ring 2," solving the technical problems of secondary sealing and efficient oil scraping. Both applications address different pain points in hydrogen fuel cell engines under different operating conditions, and their technical paths are completely independent. The piston ring assembly structure of this application is as follows:

[0033] It includes a top ring 1 and an oil scraper ring 2 adapted to a hydrogen fuel cell engine. The two are combined to form a structure through size adaptation and functional synergy, which is used to simultaneously achieve sealing and oil scraping.

[0034] The top ring 1 includes a ring body 11 and a scraper 12. The lower end face of the ring body 11 is provided with a first groove 111 that runs through the circumference. The first groove 111 extends from the outer edge of the ring body 1 inward. The first groove 111 is used to embed the scraper 12, and the scraper 12 can extend and retract radially along the first groove 111. The radial extension and retraction design of the scraper 12 can adapt to changes in cylinder wall clearance and ensure sealing fit. The inner side of the lower end face of the ring body 11 forms a radial extension corresponding to the first groove 111. The first protrusion 113 extends, and the radial width of the first protrusion 113 meets the structural strength requirements of the ring body 11. The ring body 11 and the scraper 12 are respectively provided with a first opening 112 and a second opening 121 that penetrate both radially and axially. The circumferential offset angle α between the first opening 112 and the second opening 121 satisfies 90°≤α≤180°. The non-acute angle of 90°~180° ensures that the circumferential offset distance of the openings is sufficient, and the gas needs to take a longer detour to pass through the opening, which greatly improves the gas leakage resistance.

[0035] The oil scraper ring 2 is a nose-shaped integrated structure. The lower end face of the oil scraper ring 2 has a second groove 21 that extends circumferentially. The second groove 21 extends inward from the outer edge of the oil scraper ring 2, with its bottom inclined downwards towards the outer edge. The angle β between the bottom of the second groove 21 and its vertical sidewall satisfies 75°≤β<90°. The inclined bottom guides the scraped oil to flow back quickly to the crankcase, preventing oil stagnation. A nose opening 22 is formed corresponding to the upper part of the second groove 21. The outer circular surface of the nose opening 22 is a conical surface 23. The conical surface 23 extends from the second groove 21... The bottom of the groove is inclined towards the center of the oil scraper ring 2, and its inclination angle γ satisfies 1°≤γ≤2°. The conical surface 23 design can enhance the sealing effect with the cylinder wall and at the same time assist in scraping off residual oil from the cylinder wall. The lower inner end of the oil scraper ring 2 is provided with a chamfered notch 24 along the circumferential direction. The oil scraper ring 2 is installed in the piston groove. When the piston reciprocates during operation, the lower inner end of the oil scraper ring 2 contacts the lower end face of the piston groove. The chamfered notch 24 at the lower end can form an oil guiding surface, allowing the scraped oil to flow more smoothly into the crankcase, avoiding stagnation at the lower inner end of the oil scraper ring 2, reducing contact friction with the bottom of the piston groove during movement, and improving the smoothness of movement.

[0036] It should be noted that after the top ring 1 is assembled, the scraper 12 and the first groove 111 of the ring body 11 form an embedded fit. This structural design allows the scraper 12 to extend and retract only in the radial direction of the first groove 111 to adapt to the cylinder wall clearance. The circumferential fit between the scraper 12 and the first groove 111 has no relative displacement space. Therefore, the circumferential offset angle α between the first opening 112 of the ring body 11 and the second opening 121 of the scraper 12 almost remains at the assembly setting value and will not change with the reciprocating motion of the piston 2. Specifically, the appropriate model can be selected based on the vehicle's operating conditions to suit the usage needs of different hydrogen-powered vehicles. For example, for low-load vehicles primarily used for low-speed, short-distance travel (such as hydrogen-powered small urban commuter vehicles and short-distance delivery minivans), a top ring 1 with α=100°~110° can be selected. At this angle, the engine gas pressure is relatively low. This angle can both block direct gas leakage by staggering the openings and ensure the radial extension and retraction flexibility of the scraper 12, reducing structural rigidity redundancy and frictional power consumption. For medium-load vehicles that balance urban commuting and high-speed driving (such as hydrogen-powered compact family cars), the appropriate model can be selected. For SUVs, mid-size sedans, and intercity logistics light trucks, a top ring of α=120°~130° can be selected, balancing sealing performance and structural adaptability, stably withstanding medium gas pressure, and suitable for most common usage scenarios. For high-load vehicles with long-term heavy loads and high power output (such as hydrogen-powered heavy-duty freight trucks, engineering vehicles, and high-power commercial vehicles), a top ring of α=150°~160° can be selected. This extends the gas leakage path through a larger circumferential offset distance, improving sealing redundancy and effectively resisting the risk of gas leakage under high gas pressure. All angle selections are based on the structural characteristic that α remains constant after top ring assembly, and the angle range avoids interference at the opening edge, ensuring the proper functioning of the scraper extension and retraction function, and achieving precise matching of sealing performance for different vehicle types under different operating conditions.

[0037] In some examples of this embodiment, such as Figures 2-5As shown, the axial height of the top ring 1 is H, and the axial thickness of the scraper ring 2 is D. H and D satisfy 1.5D ≤ H ≤ 2.5D. From a sealing coordination perspective, H ≥ 1.5D ensures that the top ring 1 has sufficient axial structural strength to maintain the radial extension sealing force of its scraper 12. If H is too small (< 1.5D), the top ring 1 itself lacks rigidity, and the sealing pressure of the scraper 12 easily decreases, leading to a large amount of gas leakage into the scraper ring 2 area. This forces the scraper ring 2 to simultaneously bear the dual heavy load of "secondary sealing + oil scraping," resulting in a sharp drop in scraping efficiency and accelerated wear of the cone surface 23 of the scraper ring 2 due to gas impact. From an oil scraping coordination perspective, H ≤ 2.5D ensures that the piston ring land (the structure between two independent piston grooves) between the top ring 1 and the scraper ring 2 has a reasonable axial width. If H is too large (> 2.5D), it will cause the axial distance between the piston land where the top ring 1 is located and the piston groove where the scraper ring 2 is located to increase. If the distance between the top ring and the oil scraper ring is too short, it will shorten the gas leakage path, and the residual gas that is not intercepted by the top ring will more easily enter the oil scraper ring 2 area, increasing the sealing load of the oil scraper ring 2. If the ring land width is insufficient, it will compress the oil return channel. The oil scraped by the oil scraper ring 2 will have difficulty flowing back to the crankcase smoothly through the ring land area, and will easily accumulate at the ring land and run up the cylinder wall, affecting the thoroughness of oil scraping. However, the ratio range of 1.5D to 2.5D allows the top ring 1 and the oil scraper ring 2 to form a pressure distribution mechanism of "top ring main seal + oil scraper ring auxiliary seal + high-efficiency oil scraping". The top ring intercepts more than 80% of the gas pressure, and the oil scraper ring 2 only bears a small amount of residual gas sealing, which can focus on the oil scraping efficiency. At the same time, the reasonable ring land width extends the gas leakage path and widens the oil return channel, making it easier for the residual gas to be sealed by the conical surface of the oil scraper ring 2. The scraped oil flows back quickly, further strengthening the synergistic effect of "sealing-oil scraping-return".

[0038] In other examples of this embodiment, such as Figure 4 and 5 As shown, the vertical sidewall of the second groove transitions smoothly to the bottom of the groove with a circular arc 25. The radius r1 of the circular arc 25 satisfies 0.1mm ≤ r1 ≤ 0.3mm. The circular arc 25 transition reduces stress concentration, preventing the oil scraper ring 2 from breaking due to excessive stress during reciprocating motion, thus improving structural stability. The depth a of the second groove 21 (i.e., the height of the vertical sidewall) satisfies... D≤a≤ D, the slot width b (i.e., the radially extended width) satisfies D≤b≤ D. The design of the groove depth to groove width ratio ensures the effectiveness of the oil scraping channel without compromising the overall structural strength of the oil scraper ring 2. If the depth a is too small, the axial space of the oil scraping channel will be insufficient, and the oil scraped by the conical surface will not flow quickly into the second groove 21, easily accumulating and overflowing at the groove opening, affecting the oil scraping efficiency. If the depth a is too large, the vertical side wall thickness will be too thin, and the oil scraper ring 2 will be prone to deformation or breakage due to stress concentration during high-speed reciprocating motion. At the same time, it may also lead to insufficient height of the nose 22, affecting the sealing effect. If the groove width b is too small, it will restrict the radial flow space of the oil, causing backflow to be obstructed, and the oil will stagnate in the second groove 21, or even run upward along the cylinder wall into the combustion chamber. If the groove width b is too large, it will excessively weaken the radial structural strength of the oil scraper ring 2, reduce its fit stability with the piston groove, and may also lead to stress concentration at the transition between the second groove 21 and the nose 22, affecting its service life. Preferably, the angle β between the bottom of the second groove 21 and the vertical sidewall satisfies 80°≤β≤85°, and the surface roughness Ra of the bottom of the groove is ≤0.8μm. Low surface roughness can reduce the adhesion of engine oil to the bottom of the groove, improve the oil return efficiency, and reduce friction loss.

[0039] In some other examples of this embodiment, such as Figure 4 and 5 As shown, the axial height h of the nose 22 satisfies 1.2a≤h≤2a, ensuring h>a, which means the height of the nose 22 is greater than the depth of the second groove. This ensures the effective contact area between the conical surface and the cylinder liner bore, improving the synergistic effect of sealing and oil scraping. The upper end face of the nose is an arc-shaped surface, and the radius r2 of the arc-shaped surface satisfies 2D≤r2≤4D. The arc-shaped surface optimizes the contact characteristics with the cylinder wall, reduces frictional resistance, and avoids sharp edges scratching the cylinder wall.

[0040] In other examples of this embodiment, such as Figure 4 and 5 As shown, the inclination angle γ of the conical surface 23 satisfies 1.5°≤γ≤1.8°, and the transition between the conical surface 23 and the upper end face of the nose 22 is provided with a rounded corner 26. The radius r3 of the rounded corner 26 satisfies 0.05mm≤r3≤0.15mm. The transition rounded corner 26 can further reduce stress concentration and improve the wear resistance and service life of the nose 22 structure.

[0041] In other examples of this embodiment, such as Figure 4 and 5 As shown, the chamfered notch 24 is a 45° right-angle chamfer, and its chamfer depth e (axial depth) satisfies D≤e≤ D, the chamfer width f (radial width) satisfies D≤f≤ D. The design of chamfer depth and width being approximately equal ensures that the oil return flow is not obstructed due to the size being too small, thus guaranteeing the structural strength of the lower inner side of the oil scraper ring 2; it also avoids the local wall thickness being too thin due to the chamfer being too large, which could lead to stress concentration and breakage during high-speed reciprocating motion; the 45° chamfer matching this size can further reduce the oil flow resistance and improve the oil guiding efficiency.

[0042] Specifically, the materials of the ring body 11 and the oil scraper ring 2 involved in this application are both martensitic stainless steel or alloy cast iron, specifically 1Cr13. Martensitic stainless steel has good wear resistance and corrosion resistance, which is suitable for the working environment of hydrogen fuel cell engines. The material of the scraper 12 is an elastic alloy, specifically 65Mn. The elastic alloy material can ensure the radial expansion and contraction performance of the scraper 12 and ensure the reliability of the seal.

[0043] Those skilled in the art will recognize that numerous variations are possible with respect to the above description, and the embodiments and figures are merely for describing one or more specific implementations.

[0044] Although exemplary embodiments of the present invention have been described and illustrated, those skilled in the art will understand that various changes and substitutions can be made thereto without departing from the spirit of the present invention. Furthermore, many modifications can be made to adapt specific situations to the doctrine of the present invention without departing from the central concept of the present invention described herein. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but may include all embodiments and equivalents that fall within the scope of the present invention.

Claims

1. A piston ring assembly for reducing blow-by gas and oil consumption in a hydrogen-fired engine, characterized in that, This includes a top ring and an oil scraper ring adapted to hydrogen fuel cells. The two are combined to form a structure through size adaptation and functional synergy, which is used to simultaneously achieve sealing and oil scraping. The top ring includes a ring body and a scraper. The lower end face of the ring body is provided with a first groove that runs through the circumference. The first groove extends from the outer edge of the ring body inward. The first groove is used to embed the scraper, and the scraper can extend and retract radially along the first groove. The ring body and the scraper are respectively provided with a first opening and a second opening that both penetrate radially and axially. The first opening and the second opening are offset by an angle α on the circumference, which satisfies 90°≤α≤180°. The oil scraper ring is a nose-shaped integrated structure. The lower end face of the oil scraper ring is provided with a second groove that runs through the circumference. The second groove extends inward from the outer edge of the oil scraper ring, and its bottom is inclined downward toward the outer edge of the oil scraper ring. The angle β between the bottom of the second groove and the vertical sidewall of the second groove satisfies 75°≤β<90°. A nose opening is formed by protrusions at the upper part of the second groove. The outer circular surface of the nose opening is a conical surface. The conical surface is inclined from the bottom of the second groove toward the center of the oil scraper ring, and its inclination angle γ satisfies 1°≤γ≤2°. The lower inner end of the oil scraper ring is provided with a chamfered notch along the circumference.

2. The piston ring assembly for reducing blow-by and oil consumption in a hydrogen-fueled engine according to claim 1, characterized in that: The axial height of the top ring is H, and the axial thickness of the oil scraper ring is D, wherein H and D satisfy 1.5D≤H≤2.5D.

3. The piston ring assembly for reducing blow-by and oil consumption in a hydrogen-fired engine according to claim 1 or 2, characterized in that: The vertical sidewall of the second groove and the bottom of the groove are smoothly transitioned by a circular arc, and the radius of the circular arc r1 satisfies 0.1mm≤r1≤0.3mm.

4. The piston ring assembly for reducing blow-by and oil consumption in a hydrogen-fueled engine according to claim 2, characterized in that: The depth 'a' of the second groove satisfies D≤a≤ D, the slot width b satisfies D≤b≤ D.

5. The piston ring assembly for reducing blow-by and oil consumption in a hydrogen-fired engine according to claim 4, characterized in that: The axial height h of the nostril satisfies 1.2a≤h≤2a.

6. The piston ring assembly for reducing blow-by gas and oil consumption in a hydrogen-fired engine according to claim 2 or 5, characterized in that: The upper surface of the nasal opening is an arc-shaped surface, and the radius r2 of the arc-shaped surface satisfies 2D≤r2≤4D.

7. The piston ring assembly for reducing blow-by and oil consumption in a hydrogen-fired engine according to claim 1, characterized in that: The transition between the conical surface and the upper end face of the nose is provided with a rounded corner, and the radius of the rounded corner r3 satisfies 0.05mm≤r3≤0.15mm.

8. The piston ring assembly for reducing blow-by and oil consumption in a hydrogen-fired engine according to claim 2, characterized in that: The chamfer notch is a 45° right-angle chamfer, and its chamfer depth e satisfies D≤e≤ D, the chamfer width f satisfies D≤f≤ D.

9. The piston ring assembly for reducing blow-by and oil consumption in a hydrogen-fired engine according to claim 1, characterized in that: The surface roughness Ra of the bottom of the second groove is ≤0.8μm.

10. The piston ring assembly for reducing blow-by gas and oil consumption in a hydrogen-fired engine according to claim 1, characterized in that: The ring body and the oil scraper ring are both made of martensitic stainless steel or alloy cast iron, and the scraper blade is made of elastic alloy.

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