Active-passive fusion type pre-combustion chamber jet ignition system

Abstract

The invention provides an active-passive fusion type pre-combustion chamber jet ignition system which comprises a pre-combustion chamber shell, a spark plug and an oil sprayer, the pre-combustion chamber shell and the oil sprayer are arranged at the top end of a cylinder cover at intervals, and the spark plug is arranged on the pre-combustion chamber shell; an oil inlet hole and a jet hole which are communicated with a main combustion chamber of an engine are formed in the pre-combustion chamber shell, a first oil injection hole and a second oil injection hole are formed in the oil injector, fuel injected from the first oil injection hole enters a pre-combustion chamber cavity through the oil inlet hole to form pre-combustion chamber mixed gas, and fuel injected from the second oil injection hole enters the main combustion chamber to form pre-combustion chamber mixed gas. And the jet flow hole is used for jetting main jet flow flames to the main combustion chamber, and then the main combustion chamber mixed gas in the main combustion chamber is ignited. The pre-combustion chamber can integrate the advantages of an active pre-combustion chamber and a passive pre-combustion chamber, the aim of improving jet flow flame energy of the pre-combustion chamber of a novel structure is achieved, and the problems of engine lean burn limit widening and cold start are solved.

Description

Technical Field

[0001] This application belongs to the field of internal combustion engine technology, and in particular relates to an active-passive fusion pre-combustion chamber jet ignition system. Background Technology

[0002] Global climate and environmental issues pose severe challenges to the future development of humankind. Petroleum, as a primary energy source, has limited reserves and its use is accompanied by the production of pollutants. Therefore, an increasing number of researchers worldwide are dedicated to developing low-carbon and zero-carbon alternative fuels. Methanol, as a representative alternative fuel, has a wide range of sources and low production costs; however, misfires often occur when using spark plug ignition under low-load and lean-burn conditions. With the advancement of modern science and technology, pre-combustion chamber jet ignition technology, capable of solving these problems, has emerged.

[0003] Pre-combustion chamber jet ignition technology is generally divided into two categories: active and passive. Both have the common feature of installing a spark plug in the pre-combustion chamber and setting an injection orifice at the lower end of the pre-combustion chamber. The difference is that the active pre-combustion chamber has an injector to supply fuel to the pre-combustion chamber, while the passive pre-combustion chamber does not have an injector to inject fuel into the pre-combustion chamber. Therefore, compared with the passive pre-combustion chamber, the advantage of the active pre-combustion chamber is that it can further widen the lean-burn limit of the engine, while the advantage of the passive pre-combustion chamber is that it is simple in structure and easy to use. The advantages of each are also the disadvantages of each other. Summary of the Invention

[0004] In view of this, this application aims to propose an active-passive fusion pre-combustion chamber jet ignition system to solve the problems of widening the lean-burn limit of the engine and cold start.

[0005] To achieve the above objectives, the technical solution of this application is implemented as follows: This application provides an active-passive fusion pre-combustion chamber jet ignition system, including a pre-combustion chamber housing, a spark plug, and an injector, wherein the pre-combustion chamber housing and the injector are spaced apart on the top of the cylinder head, and the spark plug is mounted on the pre-combustion chamber housing; The pre-combustion chamber housing is provided with an oil inlet and a jet orifice that communicate with the main combustion chamber of the engine. The injector is provided with a first injection orifice and a second injection orifice. The fuel injected from the first injection orifice enters the pre-combustion chamber cavity through the oil inlet to form a pre-combustion chamber mixture. The fuel injected from the second injection orifice enters the main combustion chamber to form a main combustion chamber mixture. The jet orifice is used to inject a main jet flame into the main combustion chamber, thereby igniting the main combustion chamber mixture.

[0006] Furthermore, the pre-combustion chamber shell is made of high-temperature and high-pressure resistant steel. The top of the pre-combustion chamber shell is pre-set with an assembly slot. The spark plug is threaded into the assembly slot. The center electrode and side electrode of the spark plug are both connected to the pre-combustion chamber cavity. When energized, the spark plug electrode generates a high-energy spark, which then ignites the combustible mixture in the pre-combustion chamber cavity.

[0007] Furthermore, the oil inlet is located at the middle end of the pre-combustion chamber housing, and the oil inlet is adjacent to the first injection hole and located on the same axis.

[0008] Furthermore, the oil inlet hole is a horizontally arranged conical hole, wherein the inner hole diameter is 2~4mm and the outer hole diameter is 4~6mm.

[0009] Furthermore, the jet orifice is a cylindrical orifice with a diameter of 2-4 mm, used for the inflow of combustible gas mixture and the injection of jet flame.

[0010] Furthermore, the pre-combustion chamber mixture formed in the pre-combustion chamber cavity is ignited by the spark plug to form a high-energy flame. The high-energy flame forms a secondary jet flame through the fuel inlet and a main jet flame through the jet orifice. The main jet flame ignites the main combustion chamber mixture in the main combustion chamber, forming a high-pressure zone to ensure stable combustion of the main combustion chamber mixture in the lean-burn state. The secondary jet flame is injected into the main combustion chamber through the fuel inlet and, under the action of the gradually expanding orifice, reduces the high-temperature impact on the injector.

[0011] Furthermore, the first injection hole is arranged horizontally, and the second injection hole is arranged at an angle; The fuel injected from the first injection hole mixes with the combustible mixture entering through the jet hole in the pre-combustion chamber to form a pre-combustion chamber mixture with an equivalence ratio of 0.8 to 1.2.

[0012] Compared with the prior art, the active-passive fusion pre-combustion chamber jet ignition system described in this application has the following advantages: (1) The active-passive fusion pre-combustion chamber jet ignition system described in this application only requires the installation of spark plugs in the pre-combustion chamber and does not require additional fuel injectors, which simplifies the structure of the pre-combustion chamber shell and has the advantages of small size, easy processing and wide application scenarios.

[0013] (2) The active-passive fusion pre-combustion chamber jet ignition system described in this application has an oil inlet in the pre-combustion chamber. This design can ensure the reliable construction of a high equivalence ratio in the pre-combustion chamber cavity, which is conducive to the formation of a highly active jet flame, thereby expanding the lean-burn limit of the engine and solving the cold start problem. Attached Figure Description

[0014] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a cross-sectional view of the pre-combustion chamber jet ignition device described in the embodiments of this application; Figure 2 This is a cross-sectional view of the injector described in the embodiment of this application; Figure 3 This is a schematic diagram of the compression stroke fuel injection and air-fuel mixture flow as described in the embodiments of this application; Figure 4 This is a schematic diagram of the jet flame generated in the pre-combustion chamber during the power stroke, as described in the embodiments of this application.

[0015] Explanation of reference numerals in the attached figures: 1-Pre-combustion chamber shell; 101-oil inlet; 102-jet orifice; 103-assembly slot; 2-spark plug; 3-injector; 301-first injection orifice; 302-second injection orifice; 303-horizontal fuel injection; 304-inclined fuel injection; 4-pre-combustion chamber mixture; 5-main combustion chamber mixture; 501-combustible mixture; 6-high-energy flame; 601-main jet flame; 602-secondary jet flame. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0017] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0018] Please see Figures 1 to 4As shown, this embodiment provides an active-passive fusion pre-combustion chamber jet ignition system, including a pre-combustion chamber housing 1, a spark plug 2, and an injector 3. The pre-combustion chamber housing 1 and the injector 3 are arranged at intervals on the top of the cylinder head, and the spark plug 2 is installed on the pre-combustion chamber housing 1. The pre-combustion chamber housing 1 is provided with an oil inlet 101 and an injection port 102 that communicate with the main combustion chamber of the engine, and the injector 3 is provided with a first injection port 301 (i.e. Figure 2 The horizontal spray hole) and the second oil spray hole 302 (i.e. Figure 2 The fuel injected from the first injection hole 301 enters the pre-combustion chamber cavity through the oil inlet hole 101 to form the pre-combustion chamber mixture 4. The fuel injected from the second injection hole 302 enters the main combustion chamber to form the main combustion chamber mixture 5. The jet hole 102 is used to inject the main jet flame 601 into the main combustion chamber, thereby igniting the main combustion chamber mixture 5 in the main combustion chamber.

[0019] This embodiment of an active-passive fusion pre-combustion chamber jet ignition system combines the advantages of both active and passive pre-combustion chambers. This pre-combustion chamber only requires the installation of spark plugs 2, eliminating the need for additional fuel injectors 3, thus simplifying the structure of the pre-combustion chamber shell 1. It has the advantages of small size, easy processing, and wide application scenarios. At the same time, the pre-combustion chamber is provided with an oil inlet 101. This design can ensure the reliable construction of a high stoichiometry ratio within the pre-combustion chamber cavity, which is conducive to the formation of highly active jet flames, thereby widening the lean-burn limit of the engine and solving the cold start problem.

[0020] In some embodiments, the top of the pre-combustion chamber housing 1 is provided with an assembly slot 103, and the spark plug 2 is threaded into the assembly slot 103. The center electrode and the side electrode of the spark plug 2 are both connected to the pre-combustion chamber cavity and are used to ignite the pre-combustion chamber mixture 4 in the pre-combustion chamber.

[0021] Specifically, in this embodiment, such as Figure 3 As shown, the pre-combustion chamber housing 1 is fixed to the engine cylinder head by a pressure plate and bolts. The spark plug 2 and the fuel injector 3 are installed on the upper end of the cylinder head. The upper end of the fuel injector 3 is connected to a fuel pipe to provide fuel to the fuel injector 3. The fuel injector 3 controls the injection frequency and injection quantity through an electrical control system, thereby forming a combustible mixture in the main combustion chamber and the pre-combustion chamber respectively. The spark plug 2 controls the energization and de-energization of the spark plug 2 through an electrical control system, thereby controlling the timing of ignition of the pre-combustion chamber mixture 4.

[0022] In some embodiments, the oil inlet 101 is located at the middle end of the pre-combustion chamber housing 1, and the oil inlet 101 is adjacent to the first injection hole 301 and located on the same axis. The oil inlet 101 is a horizontally arranged conical hole, wherein the inner hole diameter is 2~4mm and the outer hole diameter is 4~6mm; the jet hole 102 is a cylindrical hole with a cylindrical hole diameter of 2~4mm. The first injection hole 301 is horizontally arranged, and the second injection hole 302 is inclined. The fuel injected from the first injection hole 301 mixes with the combustible mixture 501 entering through the jet hole 102 in the pre-combustion chamber to form a pre-combustion chamber mixture 4 with an equivalence ratio of 0.8 to 1.2. The second injection hole 302 injects inclined fuel 304 into the main combustion chamber to form a main combustion chamber mixture 5.

[0023] Specifically, in this embodiment, during the engine compression stroke, the horizontally injected fuel 303 and the combustible mixture 501 entering through the jet orifice 102 mix in the pre-combustion chamber to form a pre-combustion chamber mixture 4 with a high equivalence ratio, ranging from 0.8 to 1.2. Since the pre-combustion chamber volume accounts for approximately 3% of the clearance volume of the main combustion chamber, even when the main combustion chamber is in a lean-burn state, the pre-combustion chamber mixture 4 can still maintain a high equivalence ratio, which is beneficial for the generation of high-energy jet flames.

[0024] In some embodiments, the pre-combustion chamber mixture 4 formed in the pre-combustion chamber cavity is ignited by the spark plug 2 to form a high-energy flame 6. The high-energy flame 6 forms a secondary jet flame 602 through the oil inlet 101 and a main jet flame 601 through the jet hole 102. The main jet flame 601 ignites the main combustion chamber mixture 5 in the main combustion chamber, so that the main combustion chamber mixture 5 in the main combustion chamber under lean combustion conditions can be stably burned.

[0025] Specifically, in this embodiment, such as Figure 4 As shown, during the engine's power stroke, the pre-combustion chamber mixture 4 is ignited by the spark plug 2 to form a high-energy flame 6. Under the influence of the high pressure difference between the main combustion chamber and the pre-combustion chamber, the high-energy flame 6 forms a small amount of secondary jet flame 602 through the fuel inlet hole 101. The gradually expanding orifice diameter reduces the high-temperature impact on the injector 3. The high-energy flame 6 forms a large amount of main jet flame 601 through the jet hole 102. The main jet flame 601 ignites the main combustion chamber mixture 5 and shortens the combustion duration of the mixture in the main combustion chamber, promoting normal and stable combustion of the mixture in the main combustion chamber under lean-burn conditions. This achieves the goal of widening the lean-burn limit range of the engine and solving the cold start problem.

[0026] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

[0027] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. An active-passive fusion pre-chamber jet ignition system, characterized in that: comprising a pre-chamber shell, a spark plug and an oil injector, wherein the pre-chamber shell and the oil injector are arranged at the top end of the cylinder head, and the spark plug is arranged on the pre-chamber shell; the pre-chamber shell is provided with an oil inlet hole and a jet hole which are in communication with the main combustion chamber, the oil injector is provided with a first oil injection hole and a second oil injection hole, the fuel injected by the first oil injection hole enters the pre-chamber cavity through the oil inlet hole to form a pre-chamber mixture, the fuel injected by the second oil injection hole enters the main combustion chamber to form a main combustion chamber mixture in the main combustion chamber, and the jet hole is used to inject a main jet flame into the main combustion chamber to ignite the main combustion chamber mixture in the main combustion chamber.

2. The active-passive fusion pre-chamber jet ignition system according to claim 1, characterized in that: the top end of the pre-chamber shell is provided with an assembly groove, the spark plug is arranged in the assembly groove through screwing, and the center electrode and the side electrode of the spark plug are in communication with the pre-chamber cavity.

3. The active-passive fusion pre-chamber jet ignition system according to claim 1, characterized in that: the oil inlet hole is located at the middle end of the pre-chamber shell, and the oil inlet hole is adjacent to the first oil injection hole and located on the same axis.

4. The active-passive fusion pre-chamber jet ignition system according to claim 3, characterized in that: the oil inlet hole is a horizontally arranged conical hole, wherein the inner hole diameter is 2-4 mm and the outer hole diameter is 4-6 mm.

5. The active-passive fusion pre-chamber jet ignition system according to claim 1, characterized in that: the jet hole is a cylindrical hole with a diameter of 2-4 mm.

6. The active-passive fusion pre-chamber jet ignition system according to claim 1, characterized in that: the pre-chamber mixture formed in the pre-chamber cavity is ignited by the spark plug to form a high-energy flame, the high-energy flame forms a secondary jet flame through the oil inlet hole and a main jet flame through the jet hole, and the main jet flame ignites the main combustion chamber mixture in the main combustion chamber to make the main combustion chamber mixture in the main combustion chamber burn stably under lean combustion conditions.

7. The active-passive fusion pre-chamber jet ignition system according to claim 6, characterized in that: the first oil injection hole is horizontally arranged, and the second oil injection hole is obliquely arranged; the fuel injected by the first oil injection hole mixes with the combustible mixture entering through the jet hole in the pre-chamber cavity to form a pre-chamber mixture with an equivalence ratio of 0.8-1.

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