Engine for a vehicle and vehicle

Abstract

The application discloses an engine and a vehicle, and relates to the field of engines, and the engine comprises a cylinder cover, an oil injector arranged on the cylinder cover and formed with an oil injection port, and a piston arranged below the cylinder cover and spaced from the cylinder cover, wherein one end of the piston towards the cylinder cover is formed with a combustion chamber, the combustion chamber is sequentially connected with a first protruding part, a second protruding part and a guide surface, the first protruding part is protruded towards the oil injection port and located in an oil injection surface of the oil injection port, the second protruding part is arranged at a top of the combustion chamber and protruded towards a gap between the cylinder cover and the piston, and the guide surface is tangent to the first protruding part and the second protruding part respectively. According to the engine provided by the application, the oil-gas mixing uniformity in the combustion chamber and the air utilization rate can be improved, and the fuel economy is improved.

Description

Technical Field

[0001] This application relates to the field of vehicles, and more particularly to an engine and a vehicle for use in vehicles. Background Technology

[0002] With increasing global focus on environmental protection and energy efficiency, engines, as key power sources in transportation, industrial machinery, and power generation, face multiple challenges, including improving fuel economy, reducing emissions, and enhancing reliability. However, after fuel injection, the distribution of the air-fuel mixture in the piston combustion chamber is not uniform, easily resulting in localized rich and lean fuel zones. This prevents the achievement of ideal combustion conditions, leading to energy loss and fuel waste, increased emissions of unburned hydrocarbons and particulate matter, and reduced thermal efficiency. Utility Model Content

[0003] This application aims to address at least one of the technical problems existing in the prior art. To this end, one objective of this application is to provide an engine for a vehicle that can improve the uniformity of air-fuel mixing and air utilization within the combustion chamber, thereby improving fuel economy.

[0004] This application also proposes a vehicle having the aforementioned engine.

[0005] An engine for a vehicle according to an embodiment of this application includes: a cylinder head; a fuel injector disposed on the cylinder head and having a fuel injection port; a piston located below the cylinder head and spaced apart from the cylinder head, a combustion chamber being formed at one end of the piston facing the cylinder head, the combustion chamber having a first protrusion, a second protrusion, and a guide surface connected in sequence, the first protrusion protruding towards the fuel injection port and located within the fuel injection surface of the fuel injection port, the second protrusion being disposed at the top of the combustion chamber and protruding towards the gap between the cylinder head and the piston, and the guide surface being tangent to the first protrusion and the second protrusion, respectively.

[0006] An engine for a vehicle according to an embodiment of this application includes a piston, a combustion chamber formed on the top of the piston, the combustion chamber may have a first protrusion, a second protrusion and a guide surface, the first protrusion may be located within the injection surface of the fuel injector, the second protrusion is located on the top of the combustion chamber, and the guide surface is tangent to the first protrusion and the second protrusion respectively. When fuel is injected through the fuel injector toward the first protrusion, part of the fuel flows through the first protrusion and is guided along the guide surface and the second protrusion to the gap between the piston and the cylinder head, where it is mixed with air, thereby making the fuel diffusion more complete and improving the uniformity of the fuel-air mixture and the air utilization rate.

[0007] In some embodiments of this application, a third protrusion extending toward the cylinder head is formed on a portion of the bottom surface of the combustion chamber. The inner diameter of the third protrusion gradually decreases along the direction of the piston toward the cylinder head. The combustion chamber also has a groove that is respectively connected to the third protrusion and the first protrusion and recessed toward the bottom of the piston.

[0008] In the above scheme, by providing a third protrusion and a groove, some fuel can be guided through the groove to the outer wall of the third protrusion and continue to diffuse along the third protrusion, thereby improving the uniformity of the fuel-air mixture and improving the air utilization rate.

[0009] In some embodiments of this application, the first protrusion is an arc protrusion along the first direction, and the radius of the first protrusion is r1 and satisfies: 0.5mm≤r1≤4.5mm, where the first direction is the extension direction of the piston.

[0010] In the above scheme, the uniformity of oil-gas mixing can be further improved by setting the radius of the first protrusion between 0.5 mm and 4.5 mm.

[0011] In some embodiments of this application, the diameter of the piston is d1, the first protrusion is annular, and the inner diameter of the first protrusion is d2, satisfying: 0.5≤d2 / d1≤0.75.

[0012] In the above scheme, by setting the ratio of the inner diameter of the first protrusion to the diameter of the piston within the above range, the air-fuel mixture concentration in the combustion chamber can be more uniform, which is beneficial to fuel consumption and emissions.

[0013] In some embodiments of this application, along the cross section in the first direction, the shortest distance between the center of the first protrusion and the top surface of the piston is h1, and the maximum distance between the groove and the top surface of the piston is h2, satisfying: 0.18≤h1 / h2≤0.5.

[0014] In the above scheme, by setting the ratio of the shortest distance between the center of the first protrusion and the top surface of the piston to the maximum distance between the groove and the top surface of the piston within the above range, the oil mist separation position can be made moderate, ensuring that the oil mist mixing at the top and bottom of the combustion chamber is more uniform.

[0015] In some embodiments of this application, the angle between the guide surface and the top surface of the piston is α and satisfies: 0 < α < 90°.

[0016] In the above scheme, by setting the angle between the guide surface and the top surface of the piston within the aforementioned range, the airflow can be guided to be compressed onto the top surface and edge of the piston, enhancing the vortex intensity and flow velocity on the piston top surface, accelerating the mixing speed of fuel and air, and improving the uniformity of the mixture.

[0017] In some embodiments of this application, the angle between the guide surface and the wall adjacent to the third protrusion along the first direction is θ and satisfies: 90° < θ < 130°.

[0018] In the above scheme, by setting the included angle between the guide surface and the wall adjacent to the third protrusion within the above range, the guide surface can strengthen and guide the clockwise rotating vortex in the middle of the combustion chamber to the groove near the central axis of the combustion chamber and the bottom when the piston moves downward, thereby accelerating the oil-air mixing at that position, improving the uniformity of oil-air mixing, and promoting combustion.

[0019] In some embodiments of this application, along the cross section in the first direction, the shortest distance between the center of the second protrusion and the top surface of the piston is h3 and satisfies: 0.1mm≤h3≤3mm; wherein, the second protrusion is tangent to the top surface of the piston.

[0020] In the above scheme, the above structure can make the edge arc of the second protrusion convex upward, forming a counterclockwise vortex near the top of the piston and above the second protrusion. Combined with the squeeze flow formed by the guide surface and the bottom surface of the cylinder head, the airflow can more easily reach the side of the piston top surface, enhance the flow field intensity, facilitate the oil-gas mixing at this position in the middle and later stages of combustion, and reduce carbon soot emissions.

[0021] In some embodiments of this application, the third protrusion is a conical protrusion, the included angle of the top of the third protrusion is β, and the included angle of the oil jet of the oil injection port is γ and satisfies: -20°≤γ-β≤20°.

[0022] In the above scheme, by setting the top angle of the third protrusion and the oil jet angle of the fuel injector within the above range, it can be ensured that the oil mist is distributed more evenly in the vertical direction along the oil jet axis, thereby improving space and air utilization.

[0023] The vehicle of an embodiment of this application is described below.

[0024] The vehicle according to the embodiments of this application is equipped with the engine of the above embodiments. Since the vehicle according to the embodiments of this application is equipped with the engine of the above embodiments, the engine of the vehicle includes a piston, and a combustion chamber is formed on the top of the piston. The combustion chamber has a first protrusion, a second protrusion and a guide surface. When fuel is injected into the first protrusion through the fuel injector, part of the fuel flows through the first protrusion and is guided along the guide surface and the second protrusion to the gap between the piston and the cylinder head, and then mixes with air. Therefore, during the operation of the vehicle, the fuel-air mixture is more uniform, the economy is better and the pollutant emissions are less, which not only meets the emission regulations but also improves emissions and fuel economy.

[0025] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0026] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0027] Figure 1 This is a schematic diagram of the engine structure according to an embodiment of this application;

[0028] Figure 2 yes Figure 1 A partial structural diagram of the piston;

[0029] Figure 3 yes Figure 2 A schematic diagram of the local method for circle A in the middle;

[0030] Figure 4 yes Figure 1 A partial structural diagram of the fuel injector and piston;

[0031] Figure 5 This is a schematic diagram of the flow field and oil mist distribution in the combustion chamber.

[0032] Figure label:

[0033] 10. Engine;

[0034] 11. Cylinder head; 12. Injector; 121. Injector port; 13. Piston;

[0035] 14. Combustion chamber; 141. First protrusion; 142. Second protrusion; 143. Guide surface;

[0036] 144. Third protrusion; 145. Groove. Detailed Implementation

[0037] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0038] The following is for reference. Figures 1-5 The present application describes an engine 10 for a vehicle, which includes a cylinder head 11, an injector 12, and a piston 13.

[0039] The fuel injector 12 is disposed on the cylinder head 11, and the fuel injector 12 forms a fuel injection port 121. The piston 13 is located below the cylinder head 11 and spaced apart from the cylinder head 11. A combustion chamber 14 is formed at one end of the piston 13 facing the cylinder head 11. The combustion chamber 14 has a first protrusion 141, a second protrusion 142 and a guide surface 143 connected in sequence. The first protrusion 141 protrudes towards the fuel injection port 121 and is located within the fuel injection surface of the fuel injection port 121. The second protrusion 142 is disposed at the top of the combustion chamber 14 and protrudes towards the gap between the cylinder head 11 and the piston 13. The guide surface 143 is tangent to the first protrusion 141 and the second protrusion 142 respectively.

[0040] Currently, the distribution of the air-fuel mixture in the piston combustion chamber is not uniform after fuel injection, which easily leads to localized areas of rich and lean fuel. This makes it impossible to achieve ideal combustion conditions, resulting in energy loss and fuel waste, increased emissions of unburned hydrocarbons and particulate matter, and reduced thermal efficiency.

[0041] In this regard, this application proposes an engine 10 for a vehicle that can improve the uniformity of fuel-air mixing and air utilization in the combustion chamber 14, thereby improving fuel economy.

[0042] Specifically, such as Figure 1 As shown, the engine 10 includes a cylinder head 11, a fuel injector 12, and a piston 13. The fuel injector 12 can be disposed at the cylinder head 11, and the fuel injector 12 can form a fuel injection port 121. The fuel injector 12 can inject fuel through the fuel injection port 121. The piston 13 can be located below the cylinder head 11. It should be noted that "below" can refer to the direction in which the cylinder head 11 faces the bottom along a first direction, and the piston 13 can be spaced apart from the cylinder head 11. The first direction can be the extension direction of the piston 13. A combustion chamber 14 can be formed at the end of the piston 13 facing the cylinder head 11. The combustion chamber 14 can be used for fuel combustion. The combustion chamber 14 has a first protrusion 141, a second protrusion 142, and a guide surface 143. The first protrusion 141, the second protrusion 142, and the guide surface 143 can be connected in sequence. The first protrusion 141 can protrude towards the fuel injector 121 and is located within the fuel injection surface of the fuel injector 121. It can be understood that fuel can be sprayed onto the first protrusion 141 through the fuel injector 121. The second protrusion 142 can be disposed at the top of the combustion chamber 14 and protrudes towards the gap between the cylinder head 11 and the piston 13. The guide surface 143 can be tangent to the first protrusion 141 and the second protrusion 142 respectively.

[0043] It should be noted that, as Figure 5As shown, when fuel is injected through the injector 121 onto the first protrusion 141, it can be split, that is, the fuel is divided into two flow paths. One part of the fuel flows to the bottom of the combustion chamber 14 and mixes with the air at the bottom, while the other part of the fuel mixes with the fresh air in the upper part of the combustion chamber 14. Alternatively, after contacting the first protrusion 141, the fuel flows along the guide surface 143 and finally flows along the second protrusion 142 to the gap between the piston 13 and the cylinder head 11 and mixes with the fresh air. It can be understood that the guide surface 143 and the second protrusion 142 can play a guiding role, so that the fuel can mix with the air in the gap between the piston 13 and the cylinder head 11, thereby improving the uniformity of the fuel-air mixture and improving the air utilization rate. While ensuring fuel economy, it minimizes the emission of hydrocarbons and particulate matter.

[0044] Furthermore, when the piston 13 is moving upwards, during the compression stroke, the guide surface 143 can accelerate the smooth breaking of airflow within the combustion chamber 14, enhance turbulent kinetic energy, improve the flow field within the combustion chamber 14, increase the combustion speed in the initial stage of combustion, shorten the duration of combustion, help advance the combustion center of gravity, and increase the effective pressure. The guide surface 143 can also guide the airflow to be squeezed onto the top and edge of the piston 13, enhance the vortex intensity and velocity on the top surface of the piston 13, accelerate the mixing speed of fuel and air, and improve the uniformity of the mixture. When the piston 13 is moving downwards, during the power stroke, the guide surface 143 can strengthen and guide the clockwise rotating vortex in the middle of the combustion chamber 14 to the vicinity of the central axis and bottom of the combustion chamber 14, accelerate the mixing of fuel and air, improve the uniformity of fuel and air, and promote combustion.

[0045] In short, the engine 10 of this application embodiment includes a piston 13, and a combustion chamber 14 is formed on the top of the piston 13. The combustion chamber 14 may have a first protrusion 141, a second protrusion 142, and a guide surface 143. The first protrusion 141 can be located within the injection surface of the fuel injector 121, the second protrusion 142 is located on the top of the combustion chamber 14, and the guide surface 143 is tangent to the first protrusion 141 and the second protrusion 142 respectively. When fuel is injected into the first protrusion 141 through the fuel injector 121, part of the fuel is diverted by the first protrusion 141 and guided along the guide surface 143 and the second protrusion 142 to the gap between the piston 13 and the cylinder head 11, and then mixed with air, thereby making the fuel diffusion more complete, improving the uniformity of the fuel-air mixture and the air utilization rate.

[0046] like Figure 2As shown in some embodiments of this application, a third protrusion 144 is formed on a portion of the bottom surface of the combustion chamber 14. The third protrusion 144 can extend toward the cylinder head 11. Along the direction of the piston 13 toward the cylinder head 11, the inner diameter of the third protrusion 144 gradually decreases. The third protrusion 144 can improve the uniformity of fuel mixing with the air in the middle of the combustion chamber 14. The combustion chamber 14 also has a groove 145. The groove 145 can be connected to the third protrusion 144 and the first protrusion 141 respectively. The groove 145 can be recessed toward the piston 13. The groove 145 can provide guidance for fuel movement and further promote fuel diffusion. By connecting the groove 145 with the first protrusion 141, fuel can flow along the groove 145 and mix with the air at the bottom of the combustion chamber 14. In addition, some fuel can be guided through the groove 145 to the outer wall of the third protrusion 144 and continue to diffuse along the third protrusion 144, thereby improving the uniformity of fuel-air mixing and improving air utilization.

[0047] Furthermore, in some embodiments, the angle between the guide surface 143 and the adjacent wall of the third protrusion 144 along the first direction is θ, satisfying the relationship: 90° < θ < 130°. It can be seen that the angle between the guide surface 143 and the adjacent wall of the third protrusion 144 can be greater than 90 degrees and less than 130 degrees. For example, the angle between the guide surface 143 and the adjacent wall of the third protrusion 144 can be, but is not limited to, 95°, 100°, 110°, 120°, etc. This arrangement allows the guide surface 143 to strengthen and guide the clockwise rotating vortex in the middle of the combustion chamber 14 to the groove 145 near the central axis and bottom of the combustion chamber 14 when the piston 13 moves downward, accelerating the fuel-air mixing at this location, improving the uniformity of fuel-air mixing, and promoting combustion. In a specific embodiment, the angle between the guide surface 143 and the adjacent wall of the third protrusion 144 is 111.58 degrees.

[0048] like Figure 2As shown, in some embodiments of this application, the first protrusion 141 is an arc protrusion along the first direction, and the radius of the first protrusion 141 is r1, satisfying the relationship: 0.5mm≤r1≤4.5mm. That is, the radius of the first protrusion 141 can be any value between 0.5mm and 4.5mm. For example, the radius of the first protrusion 141 can be, but is not limited to, 0.5mm, 1.5mm, 2.5mm, 3.5mm, 4.5mm, etc. If the radius of the first protrusion 141 is too large or too small, it will affect the vortex size of the oil mist flowing towards the top of the piston 13 at the guide surface 143 and the groove 145, thereby affecting the secondary mixing of the mixer and reducing the uniformity of the mixed gas. Therefore, setting the radius of the first protrusion 141 within the above range can further improve the uniformity of the oil-gas mixture. In some embodiments, the radius of the first protrusion 141 is 2.2mm.

[0049] like Figure 2 As shown, in some embodiments of this application, the diameter of the piston 13 is d1, and the first protrusion 141 is annular. Therefore, the first protrusion 141 has an inner diameter, and the inner diameter of the first protrusion 141 is d2, satisfying the relationship: 0.5≤d2 / d1≤0.75. That is, the ratio of the inner diameter of the first protrusion 141 to the diameter of the piston 13 can be any value between 0.5 and 0.75. For example, the ratio of the inner diameter of the first protrusion 141 to the diameter of the piston 13 can be, but is not limited to, 0.5, 0.6, 0.7, or 0. 75. If the ratio of the inner diameter of the first protrusion 141 to the diameter of the piston 13 is too small, the air-fuel mixture in the groove 145 and the bottom of the combustion chamber 14 will be too rich. If the ratio of the inner diameter of the first protrusion 141 to the diameter of the piston 13 is too large, the air-fuel mixture at the top of the piston 13 will be too rich, and the air utilization rate in the middle of the combustion chamber 14 will be low. Therefore, setting the ratio of the inner diameter of the first protrusion 141 to the diameter of the piston 13 within the above range can make the air-fuel mixture concentration in the combustion chamber 14 more uniform, which is beneficial to fuel consumption and emissions.

[0050] like Figure 2As shown, in some embodiments of this application, along the cross-section in the first direction, the shortest distance between the center of the first protrusion 141 and the top surface of the piston 13 is h1, and the maximum distance between the groove 145 and the top surface of the piston 13 is h2, satisfying the relationship: 0.18≤h1 / h2≤0.5. That is, the ratio of the shortest distance between the center of the first protrusion 141 and the top surface of the piston 13 and the maximum distance between the groove 145 and the top surface of the piston 13 can be any value between 0.18 and 0.5. For example, the ratio of the shortest distance between the center of the first protrusion 141 and the top surface of the piston 13 and the maximum distance between the groove 145 and the top surface of the piston 13 can be, but is not limited to, 0.18, 0.3, 0.4, 0.5, etc. If the ratio is smaller, the oil mist is optimally distributed. The higher the oil position, the more it is distributed at the top edge of the piston 13, resulting in poorer mixture uniformity. The weakened vortex intensity of the groove 145 at the bottom of the combustion chamber 14 further reduces the mixture uniformity at the third protrusion 144. If the ratio is larger, the position of the first protrusion 141 is closer to the bottom of the combustion chamber 14, making the optimal oil mist separation position lower, resulting in the oil mist in the combustion chamber 14 being relatively concentrated in the middle position, and the mixture being relatively poor, which is not conducive to fuel consumption and emissions. Therefore, by setting the ratio of the shortest distance between the center of the first protrusion 141 and the top surface of the piston 13 and the maximum distance between the groove 145 and the top surface of the piston 13 within the above range, the oil mist separation position can be made moderate, ensuring that the oil mist mixture at the top and bottom of the combustion chamber 14 is more uniform.

[0051] like Figure 3 As shown, in some embodiments of this application, the angle between the guide surface 143 and the top surface of the piston 13 is α, satisfying the relationship: 0 < α < 90°. It can be understood that α can represent the slope of the guide surface 143. The smaller the angle between the guide surface 143 and the top surface of the piston 13, the larger the volume formed at the top of the piston 13. The worse the vortex effect formed by the guide surface 143 on the oil mist diversion, the worse the uniformity of the air-fuel mixture in the top volume of the combustion chamber 14 of the piston 13, the lower the air utilization rate, and the higher the fuel consumption and emissions. The larger the angle between the guide surface 143 and the top surface of the piston 13, the less likely the oil mist is to divert to the top of the piston 13. The oil mist distribution is mainly in the middle and bottom of the piston 13. Similarly, the vortex at the guide surface 143 will also be weakened. While affecting the uniformity of the air-fuel mixture and thus affecting fuel consumption and emissions, it also affects the distribution of combustion temperature, with the temperature concentrated in the middle, thereby affecting the reliability of the piston 13. Therefore, setting the angle between the guide surface 143 and the top surface of the piston 13 within the above range can guide the airflow to be squeezed onto the top surface and edge of the piston 13, enhance the vortex intensity and flow velocity on the top surface of the piston 13, accelerate the mixing speed of fuel and air, and improve the uniformity of the mixture. In some embodiments, the angle between the guide surface 143 and the top surface of the piston 13 can be 45°.

[0052] like Figure 3 As shown, in some embodiments of this application, the second protrusion 142 is an arc protrusion along the cross section in the first direction, and the radius of the second protrusion 142 is r2, satisfying the relationship: 0.1mm≤r2≤3mm. That is, the radius of the second protrusion 142 can be any value between 0.1mm and 3mm. For example, the radius of the second protrusion 142 can be, but is not limited to, 0.1mm, 1mm, 2mm, 3mm, etc. This setting can improve the vortex intensity between the piston 13 and the cylinder head 11, which is beneficial to the uniformity of oil-air mixing at the top of the piston 13, improves air utilization, and reduces fuel consumption and emissions.

[0053] like Figure 3 As shown, in some embodiments of this application, along the cross-section in the first direction, the shortest distance between the center of the second protrusion 142 and the top surface of the piston 13 is h3, satisfying the relationship: 0.1mm ≤ h3 ≤ 3mm. That is, the shortest distance between the center of the second protrusion 142 and the top surface of the piston 13 can be any value between 0.1mm and 3mm. For example, the shortest distance between the center of the second protrusion 142 and the top surface of the piston 13 can be, but is not limited to, 0.1mm, 1mm, 2mm, 3mm, etc. This setting can... The edge arc of the second protrusion 142 is convex upwards, forming a counterclockwise vortex near the top of the piston 13 and above the second protrusion 142. Combined with the squeeze flow formed by the guide surface 143 and the bottom surface of the cylinder head 11, the airflow can more easily reach the side of the top surface of the piston 13, enhancing the flow field intensity and facilitating the oil-gas mixing at this position in the middle and later stages of combustion, thus reducing carbon soot emissions. In some embodiments, the second protrusion is tangent to the top surface of the piston, that is, the radius of the second protrusion 142 and the shortest distance between the center of the second protrusion 142 and the top surface of the piston 13 are the same.

[0054] like Figure 4 As shown, in some embodiments of this application, the third protrusion 144 is a conical protrusion with a top angle of β and an oil jet angle of γ at the fuel injector 121, satisfying the relationship: -20°≤γ-β≤20°. That is, the difference between the oil jet angle of the fuel injector 121 and the top angle of the third protrusion 144 can be any value between -20° and 20°. For example, the difference between the oil jet angle of the fuel injector 121 and the top angle of the third protrusion 144 can be, but is not limited to, -20°, -10°, 0, 10°, 20°, etc. This setting can ensure that the oil mist is more evenly distributed in the vertical direction along the oil jet axis, thereby improving space and air utilization.

[0055] like Figure 4As shown, in some embodiments of this application, the groove portion 145 is an arc-shaped groove along the first direction, and the radius of the groove portion 145 is r3, satisfying the relationship: 3mm≤r3≤8mm. That is, the radius of the groove portion 145 can be any value between 3mm and 8mm. For example, the radius of the groove portion 145 can be, but is not limited to, 3mm, 5mm, 6mm, 8mm, etc. By setting the radius of the groove portion 145 within the above range, the vortex intensity of the groove portion 145 after the oil mist contacts the first protrusion 141 and is diverted can be guaranteed, further improving the uniformity of fuel and air mixing at the groove portion 145. In some embodiments, the minimum distance between the center of the groove portion 145 and the top surface of the piston 13 can be any value between 7mm and 15mm. The groove portion 145 can be annular, and the ratio between the maximum inner diameter of the groove portion 145 and the diameter of the piston 13 can be any value between 0.59 and 0.7. This setting can further improve the uniformity of fuel and air mixing at the groove portion 145.

[0056] like Figure 4 As shown, in some embodiments of this application, the shortest distance between the apex of the third protrusion 144 and the top surface of the piston 13 is h4, where h4 satisfies the relationship: 3mm ≤ h4 ≤ 12mm. If the shortest distance between the apex of the third protrusion 144 and the top surface of the piston 13 is too large, the air-fuel mixture at the top of the combustion chamber 14 will be leaner, resulting in low air utilization. Therefore, setting the shortest distance between the apex of the third protrusion 144 and the top surface of the piston 13 within the aforementioned range can improve the uniformity of the air-fuel mixture. In some embodiments, the shortest distance between the apex of the third protrusion 144 and the top surface of the piston 13 is 6.71mm.

[0057] like Figure 4 and Figure 5 As shown, in some embodiments of this application, the injector 12 divides the combustion chamber 14 along the center line of the fuel jet, with the upper part accounting for 30% to 45% of the total volume. The distance between the spray landing point (i.e., the intersection of the spray center line and the inner cavity of the piston 13 combustion chamber 14) and the top surface of the piston 13 is greater than the shortest distance between the center of the first protrusion 141 and the top surface of the piston 13, and less than the shortest distance between the center of the groove 145 and the top surface of the piston 13. This is more conducive to the flow field in the groove 145. At the same time, the vortex formed on both sides of the spray by the guide surface 143 and the bottom surface of the cylinder head 11 jointly promotes the mixing of the air-fuel mixture in the middle and bottom of the piston 13 combustion chamber 14.

[0058] The vehicle of an embodiment of this application is described below.

[0059] The vehicle according to the embodiments of this application is equipped with the engine 10 of the above embodiments. Since the vehicle according to the embodiments of this application is equipped with the engine 10 of the above embodiments, the engine 10 of the vehicle includes a piston 13. A combustion chamber 14 is formed on the top of the piston 13. The combustion chamber 14 has a first protrusion 141, a second protrusion 142 and a guide surface 143. When fuel is injected into the first protrusion 141 through the fuel injector 121, part of the fuel is diverted through the first protrusion 141 and guided along the guide surface 143 and the second protrusion 142 to the gap between the piston 13 and the cylinder head 11, and then mixed with air. Therefore, during the operation of the vehicle, the fuel-air mixture is more uniform, the economy is better, and the pollutant emissions are less. It not only meets the emission regulations but also improves emissions and fuel economy.

[0060] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0061] In the description of this application, "first feature" and "second feature" may include one or more of the features.

[0062] In the description of this application, "multiple" means two or more.

[0063] In the description of this application, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or it may include the first and second features not being in direct contact but being in contact through another feature between them.

[0064] In the description of this application, the terms "above," "over," and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0065] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0066] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. An engine for a vehicle, characterized by, include: Cylinder head (11); Injector (12), the injector (12) is disposed on the cylinder head (11), and the injector (12) has an injection port (121); A piston (13) is located below the cylinder head (11) and spaced apart from the cylinder head (11). A combustion chamber (14) is formed at one end of the piston (13) facing the cylinder head (11). The combustion chamber (14) has a first protrusion (141), a second protrusion (142), and a guide surface (143) connected in sequence. The first protrusion (141) protrudes towards the fuel injector (121) and is located within the fuel injection surface of the fuel injector (121). The second protrusion (142) is located at the top of the combustion chamber (14) and protrudes towards the gap between the cylinder head (11) and the piston (13). The guide surface (143) is tangent to the first protrusion (141) and the second protrusion (142) respectively.

2. The engine for a vehicle according to claim 1, characterized by, A third protrusion (144) extending toward the cylinder head (11) is formed on a portion of the bottom surface of the combustion chamber (14). The inner diameter of the third protrusion (144) gradually decreases along the direction of the piston (13) toward the cylinder head (11). The combustion chamber (14) also has a groove (145) that is connected to the third protrusion (144) and the first protrusion (141) respectively and is recessed toward the piston (13) below.

3. The engine for a vehicle according to claim 2, characterized by, In the cross section along the first direction, the first protrusion (141) is an arc protrusion, the radius of the first protrusion (141) is r1 and satisfies: 0.5mm≤r1≤4.5mm, and the first direction is the extension direction of the piston (13).

4. The engine for a vehicle according to claim 3, characterized in that, The piston (13) has a diameter of d1, the first protrusion (141) is annular, and the inner diameter of the first protrusion (141) is d2 and satisfies: 0.5≤d2 / d1≤0.

75.

5. The engine for a vehicle according to claim 4, characterized by Along the first direction, the shortest distance between the center of the first protrusion (141) and the top surface of the piston (13) is h1, and the maximum distance between the groove (145) and the top surface of the piston (13) is h2, satisfying: 0.18≤h1 / h2≤0.

5.

6. The engine for a vehicle according to claim 2, characterized by The angle between the guide surface (143) and the top surface of the piston (13) is α and satisfies: 0 < α < 90°.

7. The engine for a vehicle according to claim 2, characterized by In the cross section along the first direction, the included angle between the guide surface (143) and the wall adjacent to the third protrusion (144) is θ and satisfies: 90° < θ < 130°.

8. The engine for a vehicle according to claim 3, characterized by, In the cross section along the first direction, the shortest distance between the center of the second protrusion (142) and the top surface of the piston (13) is h3 and satisfies: 0.1mm≤h3≤3mm; The second protrusion (142) is tangent to the top surface of the piston (13).

9. The engine for a vehicle according to claim 2, characterized by, The third protrusion (144) is a conical protrusion, the top angle of the third protrusion (144) is β, and the oil jet angle of the oil nozzle (121) is γ and satisfies: -20°≤γ-β≤20°.

10. A vehicle characterized by comprising: An engine for a vehicle including any one of claims 1-9.

Images