Engine cylinder cover and methanol compression ignition engine
By installing a centrally located methanol injector and an eccentrically located diesel injector on the engine cylinder head, the problems of cold start difficulties and occasional misfires in methanol engines are solved, achieving uniform fuel mixing and rapid start-up.
Patent Information
- Application Number
- CN202423178726.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-23
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2034-12-23
AI Technical Summary
Methanol engines suffer from difficulties in cold starting and occasional misfires, especially when the cylinder diameter is large or the ambient temperature is low.
The engine employs two fuel injectors mounted on the cylinder head. The first injector, centered, injects methanol, while the second injector, offset, injects flammable fuels such as diesel. The engine is started via compression ignition. The injector position and angle design ensures uniform fuel mixing and improves atomization.
It effectively solves the problems of cold start difficulty and occasional misfire in methanol engines, improves combustion start-up effect and fuel mixing uniformity, and ensures successful engine start-up.
Smart Images
Figure CN223825126U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of engine technology, specifically to an engine cylinder head and a methanol compression ignition engine including the cylinder head. Background Technology
[0002] A methanol engine is an engine that uses methanol as fuel to generate power. Typically, when a methanol engine is ignited, methanol is first injected into the cylinder, and then ignited by a spark plug. If the engine cylinder bore is large, the spark plug is usually located in the middle. Combined with the high latent heat of methanol vaporization (meaning vaporization requires a lot of heat), there may be localized low temperatures within the cylinder, leading to ignition failure. Furthermore, if the ambient temperature is low, cold starts of the engine can be difficult due to the combination of the low ambient temperature and the high latent heat of methanol vaporization. Utility Model Content
[0003] In view of this, this application aims to provide an engine cylinder head that, through the structural design of the fuel injector, enables effective compression ignition, with the goal of solving the problems of difficult cold starts and occasional misfires in methanol engines.
[0004] This application provides an engine cylinder head, including a cylinder head body, wherein one or more sealing portions for sealing cylinders are provided on the cylinder head body;
[0005] The cover portion is provided with a first injector for injecting a first fuel into the cylinder and a second injector for injecting a second fuel into the cylinder. The first injector is located in the center of the cover portion, and the second injector is located on one side of the first injector and has a distance between them.
[0006] The nozzle of the first injector protrudes from the inner cylinder surface and has a plurality of first nozzles arranged circumferentially. The nozzle of the second injector protrudes from the inner cylinder surface and has at least two second nozzles on the side facing the first injector.
[0007] In one possible implementation, the central axis of the first injector is perpendicular to the inner cylinder surface.
[0008] In one possible implementation, the angle between the central axis of the second injector and the inner cylinder surface is 90°-110°, and when the angle is greater than 90°, it tilts away from the first injector.
[0009] In one possible implementation, the angle between the central axis of the first nozzle and the inner cylinder surface is 10°-35°; and / or, the angle between the central axis of the second nozzle and the inner cylinder surface is 10°-35°.
[0010] In one possible implementation, there are two second nozzles; the two second nozzles are at an angle of 30°-70° in the horizontal plane and are symmetrically distributed on both sides of the line connecting the central axis of the first injector and the central axis of the second injector.
[0011] In one possible implementation, the vertical distance from the central axis of the second injector to the central axis of the cover portion is L, the radius of the cylinder is R, and the ratio of L to R is 0.6-0.9.
[0012] In one possible implementation, the cover portion is further provided with two air inlets located on one axial side of the first injector and two exhaust ports located on the other axial side of the first injector, and the second injector is located between one of the air inlets and one of the exhaust ports that are adjacent in the circumferential direction.
[0013] In one possible implementation, the cylinder head body has an upper water chamber and a lower water chamber; the cover portion has a through hole for accommodating the second injector, the through hole including a first section located in the upper water chamber, a second section located in the partition separating the upper water chamber and the lower water chamber, and a third section located in the lower water chamber; the second injector is disposed in the through hole via a spacer sleeve;
[0014] The spacer has a first sleeve section located within the first hole section, an outer protrusion located within the second hole section, and a second sleeve section located within the third hole section;
[0015] The spacer is an integral structure, and the outer protrusion protrudes from the first sleeve segment and the second sleeve segment and is used to block the second hole segment.
[0016] This application also provides a methanol compression ignition engine, including an engine block and an engine cylinder head as described in any of the preceding claims, wherein the first injector is a methanol injector and the second injector is a diesel injector.
[0017] This application also provides an engine, including an engine block and an engine cylinder head as described in any of the preceding claims.
[0018] The engine cylinder head provided in this application has two fuel injectors on each cover section, meaning two fuel injectors are configured for each cylinder. The first fuel injector is centrally located and can inject methanol, while the second fuel injector is off-center and can inject ignition fuels such as diesel. During engine start-up, depending on the situation, such as a cold start, a flammable ignition fuel can be injected for effective combustion and starting via compression ignition. Simultaneously, the centrally located first fuel injector with multiple nozzles sprays methanol in all directions, while the off-center second fuel injector with at least two nozzles sprays diesel towards the first injector. This not only facilitates adjustment of the ratio of the two fuels but also ensures rapid and uniform mixing of diesel and methanol, preventing excessive dispersion and improving fuel-air atomization and mixing, thus enhancing combustion and starting performance. Therefore, using this engine cylinder head in a methanol-fueled engine can solve the problems of difficult cold starts and occasional misfires in methanol engines. Attached Figure Description
[0019] Figure 1 The figure shown is a schematic diagram of the inner cylinder surface of the cylinder head in an embodiment of this application;
[0020] Figure 2 The diagram shown is a schematic representation of the included angle of the second nozzle in an embodiment of this application;
[0021] Figure 3 The diagram shown is a schematic cross-sectional view of the cylinder head in an embodiment of this application.
[0022] Figures 1-3 middle:
[0023] 1. Cylinder head body; 11. Cover part; 2. Intake port; 3. Exhaust port; 4. First injector; 5. Second injector; 6. Piston; 7. Spacer; 71. Outer boss; 8. Upper water chamber; 9. Lower water chamber; 10. Baffle plate. Detailed Implementation
[0024] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0025] Please refer to the attached document. Figures 1-3This application provides an engine cylinder head that is fitted onto the engine block. It can be a single-cylinder cylinder head or an integrated cylinder head for multiple cylinders. The engine cylinder head includes a cylinder head body 1, on which one or more sealing portions 11 for sealing cylinders are provided. Each sealing portion 11 is provided with a first injector 4 for injecting a first fuel into the cylinder and a second injector 5 for injecting a second fuel into the cylinder. The first injector 4 is located in the center of the sealing portion 11, and the second injector 5 is located to one side of the first injector 4, with a distance between them. That is, the first injector 4 is centrally located, and the second injector 5 is off-center. Thus, the first injector 4 can be used to inject methanol, and the second injector 5 can be used to inject flammable fuels such as diesel. Meanwhile, the nozzle of the first injector 4 protrudes from the inner cylinder surface (referring to the cylinder surface on the side of the cylinder head that covers the cylinder) and has multiple first nozzles arranged circumferentially. If the multiple first nozzles are evenly arranged circumferentially, methanol can be injected simultaneously from multiple angles and directions, which is beneficial for the uniform distribution of methanol in the combustion chamber. The nozzle of the second injector 5 protrudes from the inner cylinder surface and has at least two second nozzles on the side facing the first injector 4. In this way, the second injector 5 can spray two jets of diesel fuel at the same time, which is beneficial for increasing the initial injection volume during startup. Moreover, the second nozzles spray towards the first injector 4, so that the diesel fuel spray is injected into the injection and dispersion area of methanol, which is beneficial for the two fuels to mix quickly and evenly, rather than being dispersed over a long distance. When the engine starts, due to the setting of flammable fuel, a compression ignition starting mode can be used. The piston 6 in the cylinder compresses the atomized fuel, which reaches the diesel ignition point and causes the diesel fuel to burn, igniting the methanol, thus successfully starting the engine.
[0026] As can be seen, in this application, each cylinder head cap 11 is equipped with two fuel injectors, meaning each cylinder has two fuel injectors. The first fuel injector 4 is centrally located and can be used to inject methanol, while the second fuel injector 5 is off-center and can be used to inject ignition fuels such as diesel. When the engine starts, depending on the situation, such as a cold start, a flammable ignition fuel can be injected for effective combustion and starting via compression ignition. Simultaneously, the first fuel injector 4, centrally located with multiple nozzles, sprays methanol in all directions, while the second fuel injector 5, off-center with at least two nozzles, sprays diesel towards the first injector. This not only facilitates adjusting the ratio of the two fuels but also ensures rapid and uniform mixing of diesel and methanol, preventing excessive dispersion and reducing the mixing effect of the two fuels. This improves the fuel-air atomization mixing effect, ensuring successful and rapid starting during compression ignition, and enhancing the combustion and starting effect. Applying the engine cylinder head provided in this application to an engine using methanol as fuel can solve the problems of difficult cold starts and occasional misfires in methanol engines.
[0027] In some embodiments, the central axis of the first injector 4 is perpendicular to the inner cylinder surface. The first injector 4 is centrally located and vertically positioned, and its nozzle has multiple first nozzles arranged circumferentially, which can uniformly inject fuel into the cylinder in the circumferential direction, which is beneficial to the uniform mixing of the two fuels, as well as to improve the completeness of combustion and help improve the compression ignition start-up effect.
[0028] In some embodiments, the angle between the central axis of the second injector 5 and the inner cylinder surface is 90°-110°, and when the angle is greater than 90°, it tilts away from the first injector 4. That is, the second injector 5 can be set vertically or tilted. When set vertically, the second nozzle also faces the first injector 4 or the cylinder central axis, which is beneficial for mixing the two fuels. When the second injector 5 is tilted, it tilts away from the first injector 4, and the second nozzle also faces the first injector 4 or the cylinder central axis. The tilt angle of the second injector 5 should not be too large, and should not exceed 20°. That is, the angle between the tilted central axis and the cylinder central axis should not exceed 20°, so as to prevent the nozzle from not facing the cylinder center and affecting the fuel injection area, thus affecting the start-up.
[0029] The vertical distance from the central axis of the second injector 5 to the central axis of the cover portion 11 (which is also the central axis of the cylinder) is L, the radius of the cylinder is R, and the ratio of L to R is 0.6-0.9. This setting can prevent the second injector 5 from being too close to the first injector 4, as close-range non-parallel cross-injection would cause the two fuels to move away from each other. It can also prevent the second injector 5 from being too far to the edge and thus failing to inject fuel into the combustion chamber.
[0030] In some embodiments, the angle between the central axis of the first nozzle and the inner cylinder surface is 10°-35°; and / or, the angle between the central axis of the second nozzle and the inner cylinder surface is 10°-35°. That is, as... Figure 1 As shown, the first nozzle sprays methanol mist outwards at a downward angle, while the second nozzle sprays diesel fuel towards the center of the cylinder at a downward angle. Figure 1 and Figure 2 The cone shape in the image is a visual representation of the spray pattern. This design facilitates more uniform mixing of the two fuels and improves the evenness of their distribution throughout the combustion chamber.
[0031] In some embodiments, such as Figure 2 As shown, there are two second nozzles, with an included angle of 30°-70° in the horizontal plane, and they are symmetrically distributed on both sides of the line connecting the central axis of the first injector 4 and the central axis of the second injector 5. This optimizes the diesel injection area and effect, improves the mixing uniformity of diesel and methanol, prevents excessive dispersion leading to uneven mixing, and also facilitates rapid compression ignition.
[0032] The cover portion 11 is also provided with two air inlets 2 located on one axial side of the first injector 4 and two exhaust ports 3 located on the other axial side of the first injector 4. The second injector 5 is located between an adjacent air inlet 2 and an exhaust port 3 in the circumferential direction. The cylinder head is divided into an intake side and an exhaust side on both sides in the width direction. The second injector 5 can be located between the air inlet 2 and the exhaust port on the intake side, or it can be located between the air inlet 2 and the exhaust port on the exhaust side.
[0033] like Figure 3 As shown, the cylinder head body 1 has an upper water chamber 8 and a lower water chamber 9, both extending towards the first injector 4. The upper water chamber 8 and the lower water chamber 9 are separated by a partition 10 in the thickness direction of the cylinder head body 1, and the ends of the upper water chamber 8 and the lower water chamber 9 near the first injector 4 are connected. Coolant can flow through the upper water chamber 8 to the first injector 4 to cool the nozzle of the first injector 4, and then flow away through the lower water chamber 9; in this way, the coolant continuously flows through the nozzle of the first injector 4, continuously cooling it.
[0034] The cover portion 11 has a through hole for accommodating the second injector 5. The through hole includes a first section located in the upper water chamber 8, a second section located on the partition plate 10, and a third section located in the lower water chamber 9. At the same time, a spacer 7 is provided in the through hole, and the second injector 5 is disposed in the spacer 7. That is, the second injector 5 is disposed in the through hole through the spacer 7 to prevent it from being immersed in the coolant.
[0035] The spacer 7, along the thickness direction of the cylinder head body 1, has a first sleeve section located within the upper water chamber 8 (i.e., the first bore section), an outer boss 71 located within the second bore section, and a second sleeve section located within the lower water chamber 9 (i.e., the third bore section). The spacer 7 is an integral structure, and the outer boss 71 protrudes from the first and second sleeve sections and is used to seal the second bore section. In this way, the outer boss 71 on the spacer 7 can effectively seal the second bore section, preventing coolant in the upper water chamber 8 from flowing from the through hole into the lower water chamber 9 and affecting the coolant flow to the first injector, thus affecting the cooling effect. At the same time, by providing an integral outer boss 71 on the outer wall of the spacer 7 to seal the partition plate 10, it is easier to assemble and implement than to provide a sealing ring on the outside of the spacer 7.
[0036] This application also provides a methanol compression ignition engine, including an engine block and an engine cylinder head as described in any of the above embodiments, wherein the first injector 4 is a methanol injector and the second injector 5 is a diesel injector. This methanol compression ignition engine has the beneficial effects described in the above embodiments, which will not be repeated here.
[0037] Embodiments of this application also provide an engine, including an engine block and an engine cylinder head as described in any of the above embodiments, without limiting the types of the first injector 4 and the second injector 5, or the types of the first fuel and the second fuel. This engine has the beneficial effects described in the above embodiments, which will not be repeated here.
[0038] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.
[0039] The components and devices described in this application are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the accompanying drawings. As those skilled in the art will recognize, these components and devices can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the words “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.
[0040] It should also be noted that in the apparatus and equipment of this application, the components can be disassembled and / or reassembled. These disassemblies and / or reassemblies should be considered as equivalent solutions of this application.
[0041] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of this application. Therefore, this application is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.
[0042] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.
[0043] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications or equivalent substitutions made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. An engine cylinder head, characterized in that, Includes a cylinder head body, wherein one or more sealing portions for sealing the cylinder are provided on the cylinder head body; The cover portion is provided with a first injector for injecting a first fuel into the cylinder and a second injector for injecting a second fuel into the cylinder. The first injector is located in the center of the cover portion, and the second injector is located on one side of the first injector and has a distance between them. The nozzle of the first injector protrudes from the inner cylinder surface and has a plurality of first nozzles arranged circumferentially; the nozzle of the second injector protrudes from the inner cylinder surface and has at least two second nozzles on the side facing the first injector. The first injector is centrally located and has multiple nozzles to spray methanol in all directions, while the second injector is eccentrically located and has at least two nozzles to spray ignition fuel toward the first injector.
2. The engine cylinder head as described in claim 1, characterized in that, The central axis of the first injector is perpendicular to the inner cylinder surface.
3. The engine cylinder head as described in claim 1, characterized in that, The angle between the central axis of the second injector and the inner cylinder surface is 90°-110°, and when the angle is greater than 90°, it tilts away from the first injector.
4. The engine cylinder head as described in claim 1, characterized in that, The angle between the central axis of the first nozzle and the inner cylinder surface is 10°-35°; and / or, the angle between the central axis of the second nozzle and the inner cylinder surface is 10°-35°.
5. The engine cylinder head as described in claim 1, characterized in that, There are two second nozzles; the two second nozzles are at an angle of 30°-70° in the horizontal plane and are symmetrically distributed on both sides of the line connecting the central axis of the first injector and the central axis of the second injector.
6. The engine cylinder head as described in claim 1, characterized in that, The vertical distance from the central axis of the second injector to the central axis of the cover is L, the radius of the cylinder is R, and the ratio of L to R is 0.6-0.
9.
7. The engine cylinder head as described in claim 1, characterized in that, The cover portion is also provided with two air inlets located on one side of the first injector's axial direction and two exhaust ports located on the other side of the first injector's axial direction, and the second injector is located between one of the air inlets and one of the exhaust ports that are adjacent in the circumferential direction.
8. The engine cylinder head as claimed in claim 1, characterized in that, The cylinder head body has an upper water chamber and a lower water chamber; the cover portion has a through hole for accommodating the second injector, the through hole including a first section located in the upper water chamber, a second section located in the partition separating the upper water chamber and the lower water chamber, and a third section located in the lower water chamber; the second injector is disposed in the through hole through a spacer sleeve; The spacer has a first sleeve section located within the first hole section, an outer protrusion located within the second hole section, and a second sleeve section located within the third hole section; The spacer is an integral structure, and the outer protrusion protrudes from the first sleeve segment and the second sleeve segment and is used to block the second hole segment.
9. A methanol compression ignition engine, characterized in that, It includes an engine block and an engine cylinder head as described in any one of claims 1-8, wherein the first injector is a methanol injector and the second injector is a diesel injector.
10. An engine, characterized in that, Includes the engine block and the engine cylinder head as described in any one of claims 1-8.