Pre-combustion chamber structure

Abstract

The invention discloses a pre-combustion chamber structure which is arranged in a combined type cylinder cover and comprises a nozzle body, a pre-combustion chamber body and a high-voltage wire assembly. The nozzle body is arranged at the top of a combustion chamber of the combined type cylinder cover, an injection head of the nozzle body is exposed in the combustion chamber, the nozzle body comprises a plurality of flame injection holes, and the flame injection holes are formed in the injection head exposed in the combustion chamber; the lower end of the pre-combustion chamber body abuts against and is in butt joint with the upper end of the nozzle body. The high-voltage wire assembly penetrates through the interior of the pre-combustion chamber body and is inserted into the nozzle body. The ignition end of a sparking plug of the high-voltage wire assembly is located at the top in a combustion cavity of the nozzle body. The mixed gas entering the combustion chamber can enter the combustion cavity through the multiple flame spraying holes to be ignited by the sparking plug firstly, and flames of the ignited mixed gas are sprayed into the combustion chamber through the multiple flame spraying holes to ignite the mixed gas in the combustion chamber. Therefore, the spark plug can be directly utilized to ignite mixed gas transmitted from the piston combustion chamber.

Description

Technical Field

[0001] The invention relates to the field of engine design and manufacturing, in particular to a pre-combustion chamber structure. Background Art

[0002] The current spark-ignition piston engine generally adds a mixer to the intake manifold, injects the fuel gas at a single point, mixes the fuel gas and fresh air, and then sends them into each cylinder separately. Near the end of the cylinder compression, the mixed combustible gas is ignited by sparks.

[0003] There are generally two current ignition methods, one is to use a pre-combustion chamber with a spark plug, and the other is to directly use a spark plug.

[0004] At present, there are two types of pre-combustion chambers: passive and active. In the passive type, the combustible mixture in the pre-combustion chamber is backflowed from the cylinder, such as Figure 1 As shown, the pre-combustion chamber structure includes a cylinder head 1, a pre-combustion chamber body 4 and a spark plug 8. Among them, a first accommodating cavity 2 is arranged in the cylinder head 1, and the cylinder head 1 has a first side surface for sealing the main combustion chamber of the internal combustion engine. The pre-combustion chamber body 4 is arranged on the cylinder head 1 and protrudes from the first side surface. A pre-combustion chamber 5 is arranged inside the pre-combustion chamber body 4. The pre-combustion chamber 5 has a first inner wall and a second inner wall arranged opposite to each other, and a plurality of spray holes connected to the pre-combustion chamber 5 are opened on the first inner wall. However, the concentration of the combustible mixture in the backflow pre-combustion chamber is relatively thin, and a high-energy spark is required to ignite it. The durability and ignition stability of the spark plug are poor, the combustion and flame propagation of the mixture are unstable, the fuel consumption rate is large, and the engine is prone to misfire (the spark cannot ignite the combustible mixture in the cylinder); and Figure 1 In the technical solution, it is necessary to process the first accommodating cavity 2 and the second accommodating cavity 3, and an insertion port (not shown) is opened on the pre-combustion chamber body 4. When performing threaded installation, it is also necessary to ensure that the insertion port is directly opposite to the first accommodating cavity 2, which undoubtedly increases the difficulty of processing and assembling the accessories; furthermore, although the distance between the ignition end 9 of the spark plug 8 and the first inner wall is smaller than the distance between the ignition end 9 and the second inner wall, which is more conducive to scavenging, it is also easier for unburned mixture to accumulate in the space between the ignition end 9 and the second inner wall.

[0005] Active type means that on the basis of direct injection of combustible gas into the cylinder, the spark plug directly ignites the pure combustible gas in the pre-combustion chamber, such as Figure 2As shown, the ignition device is arranged in the cylinder head 1, and a cylinder is arranged below the cylinder head 1. The ignition device with active intake pre-combustion chamber includes: an injection mechanism 33, a spark plug 4, an intake connecting pipe 9, an intake pipe 28, a nozzle 20, a natural gas main path 29 and a natural gas branch 30. The flame is ejected and ignites the lean mixture in the cylinder combustion chamber, thereby pushing the piston in the cylinder to do work. This structure allows the gas engine to achieve fast and stable lean mixture combustion, but a check valve is generally provided, the structure is complex, maintenance is difficult, and trial production requirements are high.

[0006] The direct ignition method of the spark plug requires higher ignition energy, and has more stringent requirements on the reliability and durability of the spark plug, and there is also the problem of misfire. In addition, the intake is a single-point intake in the intake pipe. During the intake stroke, the valve opens in the early stage, and at the end of the previous exhaust stroke, there is still high-temperature and high-pressure gas in the cylinder. The high-concentration mixed gas in the intake pipe is easy to cause backfire in the intake pipe, which poses a safety hazard.

[0007] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0008] The purpose of the present invention is to provide a pre-combustion chamber structure, which can directly use the spark of the spark plug to ignite the mixed gas transmitted from the piston combustion chamber inside the nozzle, and then directly spray the burned flame into the combustion chamber. In this way, the compression ignition ratio is small and the pressure is low. The compression ignition effect is better than that of a diesel engine, and the combustion is more complete. The pre-combustion chamber structure is simple in structure and high in reliability, and can realize rapid and stable composite staged combustion of gas engines.

[0009] To achieve the above-mentioned purpose, the present invention provides a pre-combustion chamber structure, which is arranged in a composite cylinder head, and the pre-combustion chamber structure includes a nozzle body, a pre-combustion chamber body and a high-voltage wire assembly; the nozzle body is arranged at the top of the combustion chamber of the composite cylinder head, and the injection head of the nozzle body is exposed in the combustion chamber, the nozzle body includes a plurality of flame spray holes, and the plurality of flame spray holes are arranged on the injection head exposed in the combustion chamber; the lower end of the pre-combustion chamber body abuts against and docks with the upper end of the nozzle body; the high-voltage wire assembly passes through the interior of the pre-combustion chamber body and is inserted in the nozzle body, and the ignition end of the spark plug of the high-voltage wire assembly is located at the top of the combustion chamber of the nozzle body; wherein the mixture entering the combustion chamber can enter the combustion chamber through the plurality of flame spray holes and be ignited by the spark plug first, and the flame of the ignited mixture is then sprayed into the combustion chamber through the plurality of flame spray holes and ignites the mixture in the combustion chamber.

[0010] In a preferred embodiment, the axial cross-section of the injection head is a U-shaped structure, and the orientation of the multiple flame nozzles includes a nozzle hole coaxial with the longitudinal center axis of the nozzle body and arranged at the bottom end of the U-shaped structure, and multiple nozzle holes arranged around the nozzle hole at the bottom end of the U-shaped structure.

[0011] In a preferred embodiment, the included angles between the central axes of the plurality of injection holes arranged around the bottom end of the U-shaped structure and the longitudinal central axis of the nozzle body are the same or different.

[0012] In a preferred embodiment, the nozzle body also includes a threaded mounting portion and an I-shaped stop flange; the threaded mounting portion is arranged at one end of the nozzle body, the threaded mounting portion includes an internal threaded portion and an external threaded portion, the internal threaded portion is used for threaded connection with the spark plug; the I-shaped stop flange is arranged at the outer circle of the middle section of the nozzle body and extends radially outward, the nozzle body includes an upper flange and a lower flange, the lower flange is used to support the upper mounting surface of the lower mounting hole of the pre-combustion chamber structure of the composite cylinder head, the injection head is located below the lower flange and inserted into the lower mounting hole, and the external thread is located above the upper flange.

[0013] In a preferred embodiment, the pre-combustion chamber body includes an upper axial through hole and a lower axial internal thread; the upper axial through hole is used to accommodate a high-voltage wire assembly and a spark plug; the lower axial internal thread is used to be threadedly connected to the external thread of the nozzle body; wherein the lower end of the pre-combustion chamber body abuts against the top surface of the upper flange of the nozzle body to limit the axial position of the nozzle body.

[0014] In a preferred embodiment, the pre-combustion chamber structure also includes an ignition coil sleeve, which is arranged in the lower mounting hole of the pre-combustion chamber structure of the composite cylinder head, and the ignition coil sleeve includes a central through hole and a mounting flange; the central through hole is used to accommodate the high-voltage wire assembly; the mounting flange is arranged in the middle of the outer circle of the ignition coil sleeve, and extends radially outward to form a disc-shaped structure, and the mounting flange includes a plurality of annular mounting holes, and the mounting holes are used to be connected to the upper mounting plane of the upper mounting hole by bolts; wherein the lower end of the ignition coil sleeve abuts against the upper end of the pre-combustion chamber body to limit the axial limit of the pre-combustion chamber body and the nozzle body.

[0015] In a preferred embodiment, the upper mounting hole, the lower mounting hole, the ignition coil sleeve, the pre-combustion chamber body, the nozzle body, the high-voltage wire assembly and the spark plug are coaxially arranged.

[0016] In a preferred embodiment, the pre-combustion chamber structure further includes an O-ring, which is arranged between the lower plane of the mounting flange and the upper mounting plane of the upper mounting hole and between the outer wall of the pre-combustion chamber body and the inner wall of the upper mounting hole.

[0017] In a preferred embodiment, the precombustion chamber structure also includes a sealing gasket, which is arranged between the lower end face of the precombustion chamber body and the upper plane of the upper flange of the nozzle body and between the lower plane of the lower flange of the nozzle body and the upper mounting surface of the lower mounting hole of the precombustion chamber structure of the composite cylinder head.

[0018] Compared with the prior art, the pre-combustion chamber structure of the present invention has the following beneficial effects: the technical solution of the present application directly utilizes the spark of the spark plug to ignite the gas transmitted from the piston combustion chamber inside the nozzle, and then directly sprays the burned flame into the combustion chamber, so that the compression ignition ratio is small, the pressure is low, the compression ignition effect is better than that of a diesel engine, and the combustion is more complete; and the technical solution has a simple structure, high reliability, and good compression ignition effect, which can optimize the engine's in-cylinder combustion, solve the compression ignition problem that plagues lean-burn engines, reduce thermal load, improve the reliability of cylinder heads and pistons, and enhance the durability of spark plugs, and can achieve fast and stable composite staged combustion of gas engines; the key is that the main components of the technical solution are all installed in coaxially arranged upper and lower mounting holes, the components are all coaxially arranged, the processing and manufacturing are simpler, the processing quality is easy to ensure, and it is conducive to a more reasonable structural layout of the composite cylinder head. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic structural diagram of a passive pre-combustion chamber according to an embodiment of the prior art;

[0020] Figure 2 It is a structural schematic diagram of an active pre-combustion chamber according to an embodiment of the prior art;

[0021] Figure 3 is a schematic diagram of a front cross-sectional structure of a pre-combustion chamber ignition device according to an embodiment of the present invention;

[0022] Figure 4 is a schematic diagram of a longitudinal cross-sectional structure of a pre-combustion chamber body according to an embodiment of the present invention;

[0023] Figure 5 Schematic diagram of the longitudinal cross-sectional structure of a nozzle body according to one embodiment of the present invention.

[0024] Description of main reference numerals:

[0025] 1-piston, 2-composite cylinder head, 3-bolt, 4-ignition coil sleeve, 5-high-voltage wire assembly, 6-O-ring, 7-pre-combustion chamber body, 8-spark plug, 9-sealing gasket, 10-nozzle body, 11-combustion chamber, 12-combustion chamber, 101-threaded mounting portion, 102-I-shaped stop flange, 103-injection head, 104-flame nozzle, 13-structural cavity. DETAILED DESCRIPTION

[0026] The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific implementation modes.

[0027] Unless explicitly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “comprising”, etc., will be understood to include the stated elements or components but not to exclude other elements or components.

[0028] like Figures 3 to 5 As shown, according to a preferred embodiment of the present invention, a pre-combustion chamber structure is arranged in a composite cylinder head 2, and the pre-combustion chamber structure includes a nozzle body 10, a pre-combustion chamber body 7 and a high-voltage wire assembly 5; the nozzle body 10 is arranged at the top of the combustion chamber of the composite cylinder head 2, and the injection head 103 of the nozzle body 10 is exposed in the combustion chamber, and the nozzle body 10 includes a plurality of flame spray holes 104, and the plurality of flame spray holes 104 are arranged on the injection head 103 exposed in the combustion chamber; the lower end of the pre-combustion chamber body 7 abuts against and docks with the upper end of the nozzle body 10; the high-voltage wire assembly 5 passes through the interior of the pre-combustion chamber body 7 and is inserted in the nozzle body 10, and the ignition end of the spark plug 8 of the high-voltage wire assembly 5 is located at the top of the combustion chamber 11 of the nozzle body 10; wherein the mixed gas entering the combustion chamber can enter the combustion chamber 11 through the plurality of flame spray holes 104 and be ignited by the spark plug 8 first, and the flame of the ignited mixed gas is then sprayed into the combustion chamber through the plurality of flame spray holes 104 and ignites the mixed gas in the combustion chamber.

[0029] In some embodiments, the position of the injection head 103 of the nozzle body 10 exposed in the combustion chamber can be adjusted according to different models of engines and different needs. For example, it can be inserted into the combustion chamber of the piston 1 and set to reach the throat position of the combustion chamber of the piston 1. This is more beneficial and timely for igniting the mixture in the entire combustion chamber.

[0030] In some embodiments, the axial cross-section of the injection head 103 is a U-shaped structure, and the orientations of the multiple flame spray holes 104 include a spray hole coaxial with the longitudinal center axis of the nozzle body 10 and arranged at the bottom end of the U-shaped structure, and multiple spray holes arranged around the spray hole at the bottom end of the U-shaped structure.

[0031] In some embodiments, the central axis of the plurality of injection holes arranged around the bottom end of the U-shaped structure is the same or different from the longitudinal central axis of the nozzle body 10. In other words, if the central axis of the plurality of injection holes is the same as the longitudinal central axis of the nozzle body 10, a row of annular injection holes is actually provided. If the central axis of the plurality of injection holes is at a different angle to the longitudinal central axis of the nozzle body 10, multiple rows of annular injection ports can be provided, and the radial positions of the multiple rows of annular injection ports can be arranged at intervals, so that the injection angles are more diverse, which is conducive to igniting the mixture in the combustion chamber of the piston 1.

[0032] In some embodiments, the nozzle body also includes a threaded mounting portion 101 and an I-shaped stop flange 102; the threaded mounting portion 101 is arranged at one end of the nozzle body 10, and the threaded mounting portion 101 includes an internal threaded portion and an external threaded portion, and the internal threaded portion is used for threaded connection with the spark plug 8; the I-shaped stop flange 102 is arranged at the outer circle of the middle section of the nozzle body 10 and extends radially outward, and the nozzle body 10 includes an upper flange and a lower flange, and the lower flange is used to support the upper mounting surface of the lower mounting hole of the pre-combustion chamber structure of the composite cylinder head 2, and the injection head 103 is located below the lower flange and inserted into the lower mounting hole, and the external thread is located above the upper flange.

[0033] In some embodiments, the pre-combustion chamber body 7 includes an upper axial through hole and a lower axial internal thread; the upper axial through hole is used to accommodate the high-voltage wire assembly 5 and the spark plug 8; the lower axial internal thread is used to be threadedly connected to the external thread of the nozzle body 10; wherein the lower end of the pre-combustion chamber body 7 abuts against the top surface of the upper flange of the nozzle body 10, so as to limit the axial position of the nozzle body 10.

[0034] In some embodiments, the pre-combustion chamber structure also includes an ignition coil sleeve 4, which is arranged in the lower mounting hole of the pre-combustion chamber structure of the composite cylinder head 2, and the ignition coil sleeve 4 includes a central through hole and a mounting flange; the central through hole is used to accommodate the high-voltage wire assembly 5; the mounting flange is arranged in the middle of the outer circle of the ignition coil sleeve 4, and extends radially outward to form a disc-shaped structure, and the mounting flange includes a plurality of annular mounting holes, and the mounting holes are used to be connected to the upper mounting plane of the upper mounting hole through bolts 3; wherein the lower end of the ignition coil sleeve 4 abuts against the upper end of the pre-combustion chamber body 7 to limit the axial limit of the pre-combustion chamber body 7 and the nozzle body 10.

[0035] In some embodiments, the upper mounting hole, the lower mounting hole, the ignition coil sleeve 4, the pre-combustion chamber body 7, the nozzle body 10, the high-voltage wire assembly 5 and the spark plug 8 are coaxially arranged. Figure 3 This coaxially arranged structure of the technical solution of the present application is conducive to the reasonable arrangement of the structural cavity 13 of the composite cylinder head 2.

[0036] In some embodiments, the pre-combustion chamber structure further includes an O-ring 6, which is disposed between the lower plane of the mounting flange and the upper mounting plane of the upper mounting hole and between the outer wall of the pre-combustion chamber body 7 and the inner wall of the upper mounting hole.

[0037] In some embodiments, the precombustion chamber structure also includes a sealing gasket 9, which is arranged between the lower end surface of the precombustion chamber body 7 and the upper plane of the upper flange of the nozzle body 10, and between the lower plane of the lower flange of the nozzle body 10 and the upper mounting surface of the lower mounting hole of the precombustion chamber structure of the composite cylinder head 2.

[0038] In summary, the pre-combustion chamber structure of the present invention has the following advantages: the technical solution of the present application directly utilizes the spark of the spark plug to ignite the gas transmitted from the piston combustion chamber inside the nozzle, and then directly sprays the burned flame into the combustion chamber, so that the compression ignition ratio is small, the pressure is low, the compression ignition effect is better than that of a diesel engine, and the combustion is more complete; and the technical solution has a simple structure, high reliability, and good compression ignition effect, which can optimize the engine's in-cylinder combustion, solve the compression ignition problem that plagues lean-burn engines, reduce thermal load, improve the reliability of cylinder heads and pistons, and enhance the durability of spark plugs, and can achieve fast and stable composite staged combustion of gas engines; the key is that the main components of the technical solution are all installed in coaxially arranged upper and lower mounting holes, the components are all coaxially arranged, the processing and manufacturing are simpler, the processing quality is easy to ensure, and it is conducive to a more reasonable structural layout of the composite cylinder head.

[0039] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A pre-combustion chamber structure, which is arranged in a composite cylinder head, characterized in that: The pre-combustion chamber structure comprises: A nozzle body, which is arranged at the top of the combustion chamber of the composite cylinder head, and the injection head of the nozzle body is exposed in the combustion chamber, the nozzle body includes a plurality of flame spray holes, and the plurality of flame spray holes are arranged on the injection head exposed in the combustion chamber; a pre-combustion chamber body, the lower end of which abuts against and butts against the upper end of the nozzle body; and A high-voltage wire assembly passes through the interior of the pre-combustion chamber body and is inserted into the nozzle body, wherein the ignition end of the spark plug of the high-voltage wire assembly is located at the top of the combustion chamber of the nozzle body; The mixed gas entering the combustion chamber can enter the combustion cavity through the multiple flame holes and be ignited by the spark plug first, and the flame of the ignited mixed gas is then sprayed into the combustion chamber through the multiple flame holes and ignites the mixed gas in the combustion chamber.

2. The pre-combustion chamber structure according to claim 1, characterized in that: The axial cross section of the injection head is a U-shaped structure, and the orientations of the multiple flame spray holes include a spray hole coaxial with the longitudinal center axis of the nozzle body and arranged at the bottom end of the U-shaped structure, and multiple spray holes arranged around the spray hole at the bottom end of the U-shaped structure.

3. The pre-combustion chamber structure according to claim 2, characterized in that: The included angles of the central axes of the plurality of injection holes arranged around the bottom end of the U-shaped structure and the longitudinal central axis of the nozzle body are the same or different.

4. The pre-combustion chamber structure according to claim 2, characterized in that: The nozzle body also comprises: a threaded mounting portion, which is disposed at one end of the nozzle body, the threaded mounting portion comprising an internal threaded portion and an external threaded portion, the internal threaded portion being used for threaded connection with the spark plug; and An I-shaped stop flange is arranged at the outer circle of the middle section of the nozzle body and extends radially outward. The nozzle body includes an upper flange and a lower flange. The lower flange is used to abut the upper mounting surface of the lower mounting hole of the pre-combustion chamber structure of the composite cylinder head. The injection head is located below the lower flange and inserted into the lower mounting hole. The external thread is located above the upper flange.

5. The pre-combustion chamber structure according to claim 4, characterized in that: The pre-combustion chamber body comprises: an upper axial through hole for accommodating the high voltage wire assembly and the spark plug; and A lower axial internal thread, which is used for threaded connection with the external thread portion of the nozzle body; The lower end of the pre-combustion chamber body abuts against the top surface of the upper flange of the nozzle body to limit the axial position of the nozzle body.

6. The pre-combustion chamber structure according to claim 5, characterized in that: It also includes an ignition coil sleeve, which is arranged in the lower mounting hole of the pre-combustion chamber structure of the composite cylinder head, and the ignition coil sleeve includes: a central through hole for accommodating the high voltage wire assembly; and A mounting flange, which is arranged in the middle of the outer circle of the ignition coil sleeve and extends radially outward to form a disc-shaped structure, wherein the mounting flange includes a plurality of mounting holes arranged in an annular manner, and the mounting holes are used to be connected to the upper mounting plane of the upper mounting hole by bolts; The lower end of the ignition coil sleeve abuts against the upper end of the pre-combustion chamber body to limit the axial position of the pre-combustion chamber body and the nozzle body.

7. The pre-combustion chamber structure according to claim 6, characterized in that: The upper mounting hole, the lower mounting hole, the ignition coil sleeve, the pre-combustion chamber body, the nozzle body, the high-voltage wire assembly and the spark plug are coaxially arranged.

8. The pre-combustion chamber structure according to claim 6, characterized in that: It also includes an O-ring, which is arranged between the lower plane of the mounting flange and the upper mounting plane of the upper mounting hole and between the outer wall of the pre-combustion chamber body and the inner wall of the upper mounting hole.

9. The pre-combustion chamber structure according to claim 6, characterized in that: It also includes a sealing gasket, which is arranged between the lower end surface of the pre-combustion chamber body and the upper plane of the upper flange of the nozzle body, and between the lower plane of the lower flange of the nozzle body and the upper mounting surface of the lower mounting hole of the pre-combustion chamber structure of the composite cylinder head.

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