Pre-combustion chamber structure and engine

Abstract

The pre-combustion chamber structure comprises a cylinder cover, a spark plug, an oil sprayer and an adapter, the cylinder cover comprises a first installation part, a second installation part and a main combustion chamber, the spark plug is installed in a first installation cavity, the oil sprayer is installed in a second installation cavity, and the adapter is installed in a third installation cavity. A spraying hole is formed in the bottom wall of the adapter, a pre-combustion chamber is defined between the first installation part and the bottom wall of the adapter, and the main combustion chamber communicates with the pre-combustion chamber through the spraying hole. In the utility model, the spark plug and the fuel injector are closer to the cooling structure outside the cylinder cover, the spark plug and the fuel injector can be quickly cooled, the part of the cylinder cover between the first mounting part and the adapter forms the part of the outer wall of the pre-combustion chamber, and the outer wall of the cylinder cover is directly contacted with the cooling structure, so that the pre-combustion chamber can quickly dissipate heat outwards through the cylinder cover; and overhigh temperature in the pre-combustion chamber caused by heat accumulation in the pre-combustion chamber is avoided, and the risk of overheat ablation of a spark plug and an oil injector is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of engines, in particular to a pre-chamber structure and an engine. Background Art

[0002] The combustion chamber of an engine includes a main combustion chamber and a pre-chamber. The pre-chamber is communicated with the main combustion chamber through injection holes. The high-temperature and high-pressure gas generated by combustion in the pre-chamber enters the main combustion chamber through the injection holes, and a high-speed injection flame is formed in the main combustion chamber to quickly ignite the mixed gas in the main combustion chamber and complete ignition. When the engine ignites, the pre-chamber has a high temperature. In the related art, the spark plug and the fuel injector are fixed in the engine cylinder head by means of the pre-chamber structure, and the external cooling medium cannot quickly reduce the temperature of the inner cavity of the pre-chamber, resulting in a risk of overheating and ablation of the spark plug and the fuel injector. Summary of the Invention

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. For this purpose, the utility model provides a pre-chamber structure capable of reducing the risk of overheating and ablation of the spark plug and the fuel injector.

[0004] The utility model also provides an engine having the above pre-chamber structure.

[0005] According to the pre-chamber structure of the first aspect embodiment of the utility model, it includes:

[0006] A cylinder head, including a first mounting portion, a second mounting portion and a main combustion chamber. The second mounting portion is located between the first mounting portion and the main combustion chamber. The first mounting portion is provided with a first mounting cavity and a second mounting cavity, and the second mounting portion is provided with a third mounting cavity;

[0007] A spark plug, mounted in the first mounting cavity and in contact with the inner wall of the first mounting cavity;

[0008] A fuel injector, mounted in the second mounting cavity and in contact with the inner wall of the second mounting cavity;

[0009] An adapter, mounted in the third mounting cavity. The bottom wall of the adapter is provided with injection holes. A pre-chamber is defined between the first mounting portion and the bottom wall of the adapter. The main combustion chamber is communicated with the pre-chamber through the injection holes.

[0010] According to the pre-chamber structure of the embodiment of the utility model, it has at least the following beneficial effects:

[0011] In the present utility model, the spark plug and the fuel injector are both closer to the cooling structure outside the cylinder head. The spark plug and the fuel injector can be quickly cooled. A part of the cylinder head between the first mounting portion and the adapter forms a part of the outer wall of the pre - combustion chamber. Since the outer wall of the cylinder head is in direct contact with the cooling structure, the pre - combustion chamber can quickly dissipate heat outward through the cylinder head, avoiding the accumulation of heat in the pre - combustion chamber and resulting in too high a temperature in the pre - combustion chamber, and reducing the risk of overheating and ablation of the spark plug and the fuel injector.

[0012] According to some embodiments of the present utility model, there is a gap between one end of the spark plug facing the adapter;

[0013] and / or, there is a gap between one end of the fuel injector facing the adapter.

[0014] According to some embodiments of the present utility model, the adapter has a first inner cavity, the cylinder head further includes a transition portion, the first mounting portion and the second mounting portion are respectively connected to opposite ends of the transition portion, the transition portion has a second inner cavity, and the first inner cavity and the second inner cavity form the pre - combustion chamber.

[0015] According to some embodiments of the present utility model, the wall thickness of the transition portion is less than or equal to the wall thickness of the first mounting portion;

[0016] and / or, the thickness of the transition portion is less than or equal to the wall thickness of the second mounting portion.

[0017] According to some embodiments of the present utility model, the cross - sectional area of at least a part of the second inner cavity gradually increases in the direction close to the first mounting portion;

[0018] and / or, the cross - sectional area of the second inner cavity is greater than the cross - sectional area of the first inner cavity.

[0019] According to some embodiments of the present utility model, the adapter is threadedly connected to the third mounting cavity;

[0020] and / or, the spark plug is threadedly connected to the first mounting cavity;

[0021] and / or, the fuel injector is threadedly connected to the second mounting cavity.

[0022] According to some embodiments of the present utility model, the adapter is threadedly connected to the third mounting cavity, and an opening is formed at one end of the third mounting cavity facing the main combustion chamber. The adapter can be installed in the third mounting cavity through the opening.

[0023] According to some embodiments of the present utility model, the adapter includes at least one first region and at least one second region, and at least one of the injection holes is provided in both the first region and the second region. Among them,

[0024] The number of the injection holes located in the first region is different from the number of the injection holes located in the second region;

[0025] and / or, the inner diameter of the injection holes located in the first region is different from the inner diameter of the injection holes located in the second region;

[0026] and / or, the circumferential pitch of adjacent injection holes located in the first region on the adapter is different from the circumferential pitch of adjacent injection holes located in the second region on the adapter;

[0027] and / or, the included angle between the center line of the injection holes located in the first region and the center line of the adapter is different from the included angle between the center line of the injection holes located in the second region and the center line of the adapter.

[0028] According to some embodiments of the present invention, a first combustion zone and a second combustion zone are provided in the main combustion chamber, the concentration of the mixed gas in the first combustion zone is greater than that in the second combustion zone, and the flame jet flow rate in the first region is greater than the flame jet flow rate in the second region; the adapter is threadedly connected to the third installation cavity, and the end point of the lower end of the external thread of the adapter is aligned with the end point of the lower end of the internal thread of the second installation part, so that the first region faces the first combustion zone and the second region faces the second combustion zone.

[0029] An engine according to an embodiment of the second aspect of the present invention includes:

[0030] The prechamber structure according to the embodiment of the first aspect;

[0031] A cooling structure, at least wrapping the outside of the prechamber.

[0032] The additional aspects and advantages of the present invention will be partially given in the following description, partially become obvious from the following description, or be understood through the practice of the present invention. Description of the Drawings

[0033] The present invention will be further described below in conjunction with the drawings and embodiments, where:

[0034] Figure 1 is a schematic diagram of an embodiment of the prechamber structure of the present invention;

[0035] Figure 2 is Figure 1 a schematic diagram of an embodiment of the middle cylinder head;

[0036] Figure 3 is Figure 1Schematic diagram of an embodiment of the middle adapter;

[0037] Figure 4 Schematic diagram of the distribution of an embodiment of the injection holes;

[0038] Figure 5 Partial structural schematic diagram of the engine in the present invention.

[0039] Reference numerals:

[0040] Pre-chamber structure 100, cylinder head 110, first mounting portion 111, first mounting cavity 1111, second mounting cavity 1112, second mounting portion 112, third mounting cavity 1121, opening 1122, main combustion chamber 113, transition portion 114, second inner cavity 1141, spark plug 120, fuel injector 130, adapter 140, injection hole 141, first inner cavity 142, first region 143, second region 142, pre-chamber 150; cooling structure 200. Detailed description of the specific embodiment

[0041] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, in which the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation of the present invention.

[0042] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as up, down, front, back, left, right, etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0043] In the description of the present invention, the meaning of several is more than one, the meaning of multiple is more than two, and understandings such as greater than, less than, exceeding, etc. do not include the present number, and understandings such as above, below, within, etc. include the present number. If the first and second are described only for the purpose of distinguishing technical features, they should not be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0044] In the description of the present invention, unless otherwise clearly defined, words such as setting, installation, connection, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0045] In the description of the present utility model, the descriptions referring to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0046] Referring to Figure 1 and Figure 2 , in an embodiment of the present utility model, a pre-chamber structure 100 is provided. The pre-chamber structure 100 includes a cylinder head 110, a spark plug 120, an injector 130 and an adapter 140. The cylinder head 110 can cooperate with the cylinder block of the engine and is installed on the top of the cylinder block. A combustion chamber is formed inside the cylinder head 110, and high-temperature and high-pressure gas burns in the combustion chamber. The injector 130 is used to inject fuel into the combustion chamber in a timely and accurate manner. The spark plug 120 is used to introduce high-voltage electricity into the combustion chamber, and the fuel is ignited by the generated spark to generate power and ignite the combustible gas in the combustion chamber. The cylinder head 110 includes a first mounting portion 111, a second mounting portion 112 and a main combustion chamber 113. The second mounting portion 112 is located between the first mounting portion 111 and the main combustion chamber 113. The first mounting portion 111 is provided with a first mounting cavity 1111 and a second mounting cavity 1112. The second mounting portion 112 is provided with a third mounting cavity 1121. Among them, the spark plug 120 is installed in the first mounting cavity 1111 and is in contact with the inner wall of the first mounting cavity 1111. The injector 130 is installed in the second mounting cavity 1112 and is in contact with the inner wall of the second mounting cavity 1112. Both the spark plug 120 and the injector 130 are in direct contact with the cylinder head 110. The cooling structure outside the cylinder head 110 can cool the spark plug 120 and the injector 130 through the cylinder head 110, which is beneficial to the rapid cooling of the spark plug 120 and the injector 130.

[0047] The adapter 140 is installed in the third mounting cavity 1121. Referring to Figure 3 , the bottom wall of the adapter 140 is provided with a spray hole 141. A pre-chamber 150 is defined between the bottom wall of the first mounting portion 111 and the adapter 140. One end of both the first mounting cavity 1111 and the second mounting cavity 1112 penetrates through to the pre-chamber 150. The main combustion chamber 113 is communicated with the pre-chamber 150 through the spray hole 141. The main combustion chamber 113 and the pre-chamber 150 together form a combustion chamber. The injector 130 injects fuel into the pre-chamber 150. The spark generated by the spark plug 120 ignites the fuel and generates high-temperature and high-pressure gas. The high-temperature and high-pressure gas enters the main combustion chamber 113 through the spray hole 141 and forms a high-speed jet flame in the main combustion chamber 113, thereby igniting the mixed gas in the main combustion chamber 113.

[0048] Since the spark plug 120 and the fuel injector 130 are directly mounted on the cylinder head 110, there are no other components intervening between the spark plug 120 and the cylinder head 110 and between the fuel injector 130 and the cylinder head 110. Both the spark plug 120 and the fuel injector 130 are closer to the cooling structure outside the cylinder head 110, shortening the heat transfer distance between the cooling structure outside the cylinder head 110 and the spark plug 120 and between the cooling structure and the fuel injector 130, enabling rapid heat exchange between the cooling structure and the spark plug 120 and between the cooling structure and the fuel injector 130, and achieving rapid temperature reduction of the spark plug 120 and the fuel injector 130. Additionally, a part of the cylinder head 110 located between the first mounting portion 111 and the adapter 140 forms a part of the outer wall of the pre-chamber 150, and the internal space of this part is relatively close to the spark plug 120 and the fuel injector 130. Since the outer wall of the cylinder head 110 is in direct contact with the cooling structure, the pre-chamber 150 can rapidly dissipate heat to the outside through the cylinder head 110 and conduct heat exchange with the cooling structure, preventing heat accumulation in the pre-chamber 150 and resulting in too high a temperature in the pre-chamber 150, and reducing the risk of overheating and ablation of the spark plug 120 and the fuel injector 130.

[0049] In addition, in the traditional pre-chamber structure 100, mounting holes for installing the spark plug 120 and the fuel injector 130 are provided on the pre-chamber component. After the pre-chamber component is mounted and fixed on the cylinder head 110, the spark plug 120 and the fuel injector 130 are then installed in the mounting holes of the pre-chamber component, resulting in the pre-chamber 150, the fuel injector 130, and the spark plug 120 being relatively far from the external cooling structure. The heat dissipation and temperature reduction efficiency of the pre-chamber 150, the fuel injector 130, and the spark plug 120 are poor. Moreover, the pre-chamber component needs to cooperate with multiple components, the overall structural design of the pre-chamber component is relatively complex, the processing difficulty of the pre-chamber structure 100 is high, which is not conducive to improving the thermal efficiency of the engine. In the present utility model, the spark plug 120 and the fuel injector 130 are directly mounted on the cylinder head 110, and the spark plug 120, the fuel injector 130, and the adapter 140 are independent of each other. The split structural design of the spark plug 120, the fuel injector 130, and the adapter 140 simplifies the adapter 140 and the pre-chamber structure 100, has low processing and manufacturing costs, facilitates the technical improvement and thermal efficiency improvement of the pre-chamber structure 100, and has high temperature reduction efficiency for the spark plug 120, the fuel injector 130, and the adapter 140, and can effectively solve the problem of overheating and ablation of the spark plug 120 and the fuel injector 130.

[0050] It is understandable that the cylinder head 110 in the traditional engine combustion system has installation positions for the spark plug 120, the fuel injector 130, and the pre-combustion components. The cylinder head 110 in this embodiment has the same structural arrangement as the cylinder head in the traditional combustion system, and the original installation positions on the cylinder head can be directly used for installing the spark plug 120, the fuel injector 130, and the adapter 140 without the need to additionally deform the structure of the cylinder head 110, reducing the production cost of the pre-combustion chamber structure 100. Additionally, the first installation part 111 is arranged above the second installation part 112, and the second installation part 112 is arranged above the main combustion chamber 113. The cylinder head 110 can be conveniently installed on the top of the engine cylinder block, and the piston in the cylinder can cooperate with the combustion environment in the main combustion chamber 113 to enable the engine to operate continuously. The pre-combustion chamber structure 100 can be integrated into the engine combustion system and cooperate with other structures.

[0051] One end of the spark plug 120 facing the adapter 140 extends out of the first installation cavity 1111 and enters the pre-combustion chamber 150 to facilitate ignition in cooperation with the fuel injector 130. Exemplarily, the electrode at the end of the spark plug 120 extends into the pre-combustion chamber 150, and the spark generated by the electrode at the end of the spark plug 120 directly acts in the pre-combustion chamber 150 and can cooperate with the fuel injector 130 for ignition, avoiding other components from blocking the ignition position and causing ignition failure.

[0052] In one embodiment, there is a gap between one end of the spark plug 120 facing the adapter 140, that is, there is a certain distance between the spark plug 120 and the adapter 140, and the space between them is part of the pre-combustion chamber 150; by separating the spark plug 120 from the adapter 140, the internal volume of the pre-combustion chamber 150 can be increased, providing sufficient space for the spark plug 120 to ignite, achieving effective ignition of the pre-combustion chamber 150, and maintaining the surface-to-volume ratio and cross-sectional ratio of the pre-combustion chamber 150 within a preset range to provide appropriate combustion pressure and jet range for ignition. Similarly, there is a gap between one end of the fuel injector 130 facing the adapter 140, that is, there is a certain distance between the fuel injector 130 and the adapter 140, and the space between them is part of the pre-combustion chamber 150, providing sufficient space for the fuel injector 130 to inject fuel and achieving effective ignition of the pre-combustion chamber 150.

[0053] It should be noted that the spark plug 120 is located above the adapter 140, and the fuel injector 130 is located above the adapter 140. One end of the spark plug 120 facing the adapter 140 refers to the lower end of the spark plug 120 and the upper end of the adapter 140. Similarly, one end of the fuel injector 130 facing the adapter 140 refers to the lower end of the fuel injector 130 and the upper end of the adapter 140. It can be understood that by setting intervals between the spark plug 120 and the adapter 140 and between the fuel injector 130 and the adapter 140, the contact area between the pre-chamber 150 and the cooling structure can be increased, and the heat exchange rate between the pre-chamber 150 and the cooling structure can be further improved, enabling the pre-chamber 150 to quickly dissipate heat outward and enhancing the temperature reduction effect of the pre-chamber 150.

[0054] A plurality of injection holes 141 can be provided. The high-temperature and high-pressure gas in the pre-chamber 150 enters the main combustion chamber 113 through different injection holes 141, and high-speed injection flames are formed in different regions of the main combustion chamber 113, which can increase the ignition area and quickly ignite the mixed gas in the main combustion chamber 113, improving the combustion speed.

[0055] The injection holes 141 penetrate the adapter 140 along the arrangement direction of the first mounting portion 111 and the second mounting portion 112. Both ends of the injection holes 141 communicate with the pre-chamber 150 and the main combustion chamber 113 respectively, and the pre-chamber 150 realizes jet ignition through the injection holes 141. In one embodiment, both ends of the injection holes 141 penetrate to opposite ends of the adapter 140 respectively. The lower end of the injection holes 141 directly communicates with the main combustion chamber 113, and the upper end of the injection holes 141 directly communicates with the pre-chamber 150. The flow path of the high-temperature and high-pressure gas in the pre-chamber 150 into the main combustion chamber 113 is short, and the ignition efficiency is high. In another embodiment, referring to Figure 1 And Figure 3 , a first inner cavity 142 is provided inside the adapter 140. The injection holes 141 are provided on the bottom wall of the adapter 140 and penetrate the bottom wall of the adapter 140. The bottom wall of the adapter 140 and the first mounting portion 111 define the pre-chamber 150. One end of the injection holes 141 communicates with the pre-chamber 150, and the other end of the injection holes 141 communicates with the main combustion chamber 113. By providing the first inner cavity 142 inside the adapter 140, the volume of the pre-chamber 150 can be increased, providing sufficient ignition space for the spark plug 120 and the fuel injector 130, and providing appropriate combustion pressure and jet range for ignition; moreover, the contact area between the adapter 140 and the second mounting portion 112 can be increased, and the installation of the adapter 140 in the cylinder head 110 is more stable.

[0056] Specifically, the cylinder head 110 further includes a transition portion 114. The first mounting portion 111 and the second mounting portion 112 are respectively connected to opposite ends of the transition portion 114. A second inner cavity 1141 is provided inside the transition portion 114. The first inner cavity 142 communicates with the second inner cavity 1141 to form a pre-chamber 150. The electrode at the end of the spark plug 120 extends into the second inner cavity 1141 and cooperates with the fuel injector 130 for ignition in the second inner cavity 1141. The first inner cavity 142 and the second inner cavity 1141 jointly provide an ignition space. In addition, the cooling structure can be directly in contact with the outer wall of the transition portion 114, and the pre-chamber 150 is cooled through the transition portion 114, realizing rapid heat dissipation of the pre-chamber 150.

[0057] In addition, the wall thickness of the transition portion 114 can be further set to be less than or equal to the wall thickness of the first mounting portion 111. On the one hand, the structural strength of the first mounting portion 111 is improved, making the installation of the spark plug 120 and the fuel injector 130 more stable. On the other hand, the pre-chamber 150 is closer to the cooling structure outside the cylinder head 110, further improving the heat dissipation efficiency of the pre-chamber 150 and reducing the risk of overheating and ablation of the spark plug 120 and the fuel injector 130. Similarly, the wall thickness of the transition portion 114 can also be set to be less than or equal to the wall thickness of the second mounting portion 112 to improve the installation stability of the adapter 140 and increase the cooling rate of the pre-chamber 150.

[0058] In one embodiment, as Figure 2 , it is set that the cross-sectional area of at least part of the second inner cavity 1141 gradually increases in the direction close to the first mounting portion 111, that is, the cross-sectional area of the second inner cavity 1141 gradually increases from bottom to top, so that the cross-section of the transition portion 114 has a gradually increasing trend from bottom to top. On the one hand, the volume of the pre-chamber 150 is increased, enabling the pre-chamber 150 to provide sufficient ignition space, and at the same time increasing the surface area of the transition portion 114 and the contact area with the cooling structure, improving the heat dissipation efficiency of the pre-chamber 150. On the other hand, when the flame and high-temperature and high-pressure gas in the pre-chamber 150 flow from top to bottom, due to the gradually shrinking cross-sectional area of the second inner cavity 1141, better combustion pressure is provided, increasing the jet velocity of the flame and gas, and improving the ignition efficiency. In addition, the first mounting portion 111 is connected to the top of the transition portion 114, and the transition region between the transition portion 114 and the first mounting portion 111 has a relatively large cross-sectional area, providing sufficient installation space for the spark plug 120 and the fuel injector 130, making the spark plug 120 and the fuel injector 130 inclined and forming a certain angle with each other. The fuel sprayed by the fuel injector 130 is distributed around the electrode of the spark plug 120. When ignited, the concentration of the air-fuel mixture near the electrode of the spark plug 120 is high, which can improve the ignition stability and the flame propagation speed.

[0059] Further, the cross-sectional area of the second inner cavity 1141 can be set to be larger than that of the first inner cavity 142. The pre-chamber 150 forms a constriction at the first inner cavity 142. The flame and gas in the pre-chamber 150 are accelerated when passing through the first inner cavity 142, which can increase the flame injection speed and the penetration distance of the jet flame. In one embodiment, the cross-sectional area of at least a part of the second inner cavity 1141 is gradually increased from bottom to top, and the cross-sectional area of the second inner cavity 1141 is larger than that of the first inner cavity 142. The spark plug 120 and the fuel injector 130 ignite in the first inner cavity 142 to generate a flame and high-temperature and high-pressure gas. Since the cross-sectional area of the first inner cavity 142 gradually decreases and is larger than that of the second inner cavity 1141, the flame and gas are gradually accelerated during the flow along the first inner cavity 142 towards the second inner cavity 1141 and when entering the second inner cavity 1141, which can greatly increase the flame injection speed and the ignition efficiency.

[0060] The fixing method of the adapter 140 in the second installation part 112 is not limited to welding, clamping, riveting, etc., so that the adapter 140 is firmly fixed in the third installation cavity 1121. For the convenience of disassembly, assembly and later maintenance of the adapter 140, in one embodiment, the adapter 140 is threadedly connected in the third installation cavity 1121. The inner wall of the third installation cavity 1121 is provided with internal threads, and the outer wall of the adapter 140 is provided with external threads that cooperate with the internal threads. The adapter 140 can be disassembled and assembled by screwing, and the operation is relatively convenient. It should be noted that in the combustion system of a traditional engine, the pre-combustion component is threadedly connected in the cylinder head 110. The adapter 140 in this embodiment is adapted to the installation hole of the cylinder head 110 in the original engine combustion system, and the cylinder head 110 in the original system can be directly used for installation without additionally setting an installation structure for the adapter 140 in the cylinder head 110, which can reduce the production cost of the pre-chamber structure 100.

[0061] Further, an opening 1122 is formed at one end of the third installation cavity 1121 facing the main combustion chamber 113. The third installation cavity 1121 communicates with the main combustion chamber 113 through the opening 1122. The adapter 140 can be inserted through the opening 1122 and installed in the third installation cavity 1121. The disassembly and assembly of the adapter 140 are relatively convenient, and there is no need to additionally provide a channel in the cylinder head 110 to communicate with the third installation cavity 1121 for installing the adapter 140, so the processing cost of the pre-chamber structure 100 is low. It should be noted that in the combustion system of a traditional engine, a channel is provided in the cylinder head 110 that penetrates to the main combustion chamber 113 and the top of the cylinder head 110. The pre-chamber component is inserted into the channel through the top of the cylinder head 110 and installed above the main combustion chamber 113 through the channel. Then, the spark plug 120 and the fuel injector 130 are installed in the pre-chamber component, and a seal is provided in the channel to seal the channel. There are many parts in the pre-chamber structure 100, and the assembly is relatively cumbersome and complex. In this embodiment, the adapter 140 is loaded from the bottom of the cylinder head 110 upward. With the large space of the main combustion chamber 113, it can be directly inserted into the third installation cavity 1121 through the opening 1122 to complete the installation, effectively improving the installation convenience of the adapter 140 and simplifying the structure of the cylinder head 110. In addition, the spark plug 120 cooperates with the inner wall of the first installation cavity 1111, and the fuel injector 130 cooperates with the inner wall of the second installation cavity 1112. There is no need to additionally provide a sealing structure in the first installation cavity 1111 and the second installation cavity 1112, simplifying the structural composition and assembly process of the pre-chamber structure 100.

[0062] The fixing method of the spark plug 120 in the first installation part 111 is not limited to clamping, interference connection, etc., so that the spark plug 120 is firmly fixed in the first installation cavity 1111. Similarly, the fixing method of the fuel injector 130 in the first installation part 111 is not limited to clamping, interference connection, etc., so that the fuel injector 130 is firmly fixed in the second installation cavity 1112. In one embodiment, the spark plug 120 is threadedly connected in the first installation cavity 1111, and the inner wall of the first installation cavity 1111 is provided with an internal thread that cooperates with the spark plug 120. The fuel injector 130 is threadedly connected in the second installation cavity 1112, and the inner wall of the second installation cavity 1112 is provided with an internal thread that is adapted to the fuel injector 130. Both the spark plug 120 and the fuel injector 130 can be installed by screwing, so as to improve the convenience of disassembly and assembly of the spark plug 120 and the fuel injector 130. In addition, the internal thread can be processed in the installation holes of the cylinder head 110 for passing through the spark plug 120 and the fuel injector 130 in the original engine combustion system, so that the spark plug 120 and the fuel injector 130 are threadedly connected to the cylinder head 110, reducing the processing cost of the pre-chamber structure 100.

[0063] The inner wall of the first installation cavity 1111 is further provided with a first limiting portion, which abuts against the spark plug 120 along the extending direction and / or circumferential direction of the first installation cavity 1111. The first limiting portion limits the installation depth of the spark plug 120 and functions to block the rotation of the spark plug 120 within the first installation cavity 1111, so as to improve the installation accuracy of the spark plug 120 and effectively control the ignition performance of the pre-chamber 150. Exemplarily, the first installation cavity 1111 is arranged as a stepped hole, and the stepped position of the stepped hole forms the first limiting portion, which abuts against the spark plug 120 in the direction away from the second installation portion 112 to limit the insertion depth of the spark plug 120 within the first installation cavity 1111; alternatively, a protrusion protruding inwards is provided on the inner wall of the first installation cavity 1111, and the protrusion forms the first limiting portion. When the spark plug 120 is inserted to a preset depth within the first installation cavity 1111, the first limiting portion abuts against the spark plug 120 circumferentially to limit the rotation of the spark plug 120 relative to the first installation portion 111. It can be understood that the inner wall of the first installation cavity 1111 abuts against the spark plug 120 radially to limit the radial wobbling of the spark plug 120. Additionally, for the case where the spark plug 120 is threadedly connected within the first installation cavity 1111, the external thread of the spark plug 120 cooperates with the internal thread of the first installation cavity 1111, and the limiting of the spark plug 120 in the extending direction, circumferential direction and radial direction within the first installation cavity 1111 can be achieved simultaneously.

[0064] Similarly, the inner wall of the second installation cavity 1112 is further provided with a second limiting portion, which abuts against the fuel injector 130 along the extending direction and / or circumferential direction of the second installation cavity 1112. The second limiting portion limits the installation depth of the fuel injector 130 and functions to block the rotation of the fuel injector 130 within the second installation cavity 1112. The inner wall of the third installation cavity 1121 is provided with a third limiting portion, which abuts against the adapter 140 along the extending direction and / or circumferential direction of the third installation cavity 1121. The third limiting portion limits the installation depth of the adapter 140 and functions to block the rotation of the adapter 140 within the third installation cavity 1121. The second limiting portion and the third limiting portion can be set to have the same form as the first limiting portion, and will not be elaborated here.

[0065] In an embodiment, the inner wall of the second installation portion 112 is recessed outwards compared with the inner wall of the transition portion 114 near one end of the second installation portion 112 for installing the adapter 140. After the adapter 140 is installed in the second installation portion 112, the inner wall of the first inner cavity 142 does not exceed the inner wall of the second inner cavity 1141 near one end of the second installation portion 112, so as to avoid the inner wall of the adapter 140 applying resistance to the high-temperature and high-pressure flame within the first inner cavity 142. Moreover, the wall thickness of the cylinder head 110 at the second installation portion 112 is small, and the second inner cavity 1141 can be closer to the cooling structure, improving the cooling efficiency of the pre-chamber 150.

[0066] One end of the adapter 140 protruding towards the main combustion chamber 113 protrudes outside the third installation cavity 1121 and enters the main combustion chamber 113. The high-temperature and high-pressure flame ejected from the injection holes 141 can quickly contact and ignite the mixed gas in the main combustion chamber 113. One end of the injection hole 141 facing the main combustion chamber 113 forms an injection port. The surface of the adapter 140 facing the main combustion chamber 113 is set as an arc surface or a spherical crown surface to increase the distribution area of the injection port and the ignition area and improve the ignition efficiency.

[0067] In one embodiment, the injection holes 141 are symmetrically distributed based on the center line of the adapter 140, and the flame jets can be ejected more evenly in the main combustion chamber 113, and the processing and assembly of the adapter 140 are more convenient. In another embodiment, according to the turbulence intensity and the distribution of the mixture concentration in the main combustion chamber 113, the injection holes 141 are set to be asymmetrically distributed, and the injection holes 141 in different regions are set to have different diameters, numbers, angles, etc. to match the combustion requirements in different regions of the main combustion chamber 113, minimizing the combustion time, reducing the combustion duration, and improving the thermal efficiency of the engine. It should be noted that since the adapter 140, the spark plug 120, and the fuel injector 130 are separated and independent of each other, when the injection holes 141 need to be adjusted, the adapter 140 can be separately removed and replaced, and the structural design of the injection holes 141 is not affected by other components, and the processing difficulty and production cost of the adapter 140 are low.

[0068] Specifically, for the case of the asymmetric design of the injection holes 141, refer to Figure 3 and Figure 4, the adapter 140 includes at least one first region 143 and at least one second region 144. At least one of the injection holes 141 is provided in each of the first region 143 and the second region 144. In one embodiment, the number of the injection holes 141 in the first region 143 is different from the number of the injection holes 141 in the second region 144. Exemplarily, the number of the injection holes 141 in the second region 144 is set to be more than that in the first region 143. The flame jet flow rate in the second region 144 is large, and the second region 144 can be directed towards the region with a relatively high concentration of the mixed gas in the main combustion chamber 113. Or, in another embodiment, the inner diameter of the injection holes 141 in the first region 143 is different from the inner diameter of the injection holes 141 in the second region 144. Exemplarily, the inner diameter of the injection holes 141 in the second region 144 is set to be larger than the inner diameter of the injection holes 141 in the first region 143. The flame jet flow rate in the second region 144 is large, and the second region 144 can be directed towards the region with a relatively high concentration of the mixed gas in the main combustion chamber 113. Or, in another embodiment, the circumferential pitch of the adjacent injection holes 141 in the first region 143 on the adapter 140 is different from the circumferential pitch of the adjacent injection holes 141 in the second region 144 on the adapter 140. Exemplarily, the pitch between the injection holes 141 in the second region 144 is smaller than the pitch between the injection holes 141 in the first region 143. The injection holes 141 in the second region 144 are densely arranged, and the flame jet flow rate is large, and the second region 144 can be directed towards the region with a relatively high concentration of the mixed gas in the main combustion chamber 113. Or, the angle a between the center line of the injection holes 141 in the first region 143 and the adapter 140 is different from the angle a between the center line of the injection holes 141 in the second region 144 and the adapter 140. Exemplarily, the angle a in the second region 144 is set to be larger than the angle a in the first region 143. The flame jet range of the injection holes 141 in the second region 144 is large, and the second region 144 can be directed towards the edge region with a relatively high concentration of the mixed gas in the main combustion chamber 113.

[0069] It can be understood that the settings of the inner diameter, number, pitch and angle a of the injection holes 141 in the above different regions can be combined. For example, the number and inner diameter of the injection holes 141 in the first region 143 are both set to be larger than the number and inner diameter of the injection holes 141 in the second region 144. Or, the number and pitch of the injection holes 141 in the first region 143 are both set to be larger than the number and pitch of the injection holes 141 in the second region 144, and the angle a of the injection holes 141 in the first region 143 is smaller than the angle a of the injection holes 141 in the second region 144.

[0070] In one embodiment, a first combustion zone and a second combustion zone are provided in the main combustion chamber 113, and the concentration of the mixed gas in the first combustion zone is greater than that in the second combustion zone. The first region 143 of the adapter 140 faces the first combustion zone, and the second region 144 faces the second combustion zone. The flame jet flow rate in the first region 143 is greater than that in the second region 144, so that the flame jet flow rate ejected from the injection hole 141 is adapted to the concentration of the mixed gas in different regions in the main combustion chamber 113, thereby improving the engine thermal efficiency.

[0071] For the case where the adapter 140 is threadedly connected to the third installation cavity 1121, the external thread of the adapter 140 is adapted to and screwed with the internal thread of the third installation cavity 1211. The end point of the external thread at the lower end of the adapter 140 is aligned with the end point of the internal thread at the lower end of the second installation part 112. When the adapter 140 is installed on the second installation part 112, when the end point at the lower end of the external thread moves to be aligned with the end point at the lower end of the internal thread, the adapter 140 is blocked and cannot continue to move relative to the second installation part 112. At this time, the installation of the adapter 140 is completed, and the first region 143 faces the first combustion zone, and the second region 144 faces the second combustion zone. Through the cooperation of the starting positions of the threads of the adapter 140 and the second installation part 112, the assembly position of the adapter 140 and the orientations of different regions are positioned, so that the mixed gas in different regions of the pre-chamber 150 burns effectively, thereby improving the engine thermal efficiency.

[0072] Referring to Figure 5 , the present invention also provides an engine, which includes the above-mentioned pre-chamber structure 100, and further includes a cooling structure 200. The cooling structure 200 at least wraps around the outside of the pre-chamber 150. The cooling structure 200 exchanges heat with the pre-chamber 150 to achieve rapid heat dissipation of the pre-chamber 150 and reduce the risk of overheating and ablation of the spark plug 120 and the fuel injector 130.

[0073] It can be understood that for a water-cooled engine, the cooling structure 200 can be set as a cooling water jacket. In addition, the engine in the present invention can be applied to vehicles. The vehicle can be a private car, such as a sedan, an SUV, an MPV or a pickup truck, etc. The vehicle can also be an operating vehicle, such as a minibus, a bus or a truck, etc.

[0074] The above has described the embodiments of the present invention in detail with reference to the drawings. However, the present invention is not limited to the above embodiments. Within the knowledge scope of those of ordinary skill in the art to which the present invention pertains, various changes can be made without departing from the purpose of the present invention. In addition, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

Claims

1. The pre-combustion chamber structure is characterized by: include: A cylinder head, comprising a first mounting portion, a second mounting portion and a main combustion chamber, wherein the second mounting portion is located between the first mounting portion and the main combustion chamber, the first mounting portion is provided with a first mounting cavity and a second mounting cavity, and the second mounting portion is provided with a third mounting cavity; a spark plug, installed in the first installation cavity and in contact with an inner wall of the first installation cavity; a fuel injector, installed in the second installation cavity and in contact with an inner wall of the second installation cavity; An adapter is installed in the third installation cavity, a spray hole is provided on the bottom wall of the adapter, a pre-combustion chamber is defined between the first installation portion and the bottom wall of the adapter, and the main combustion chamber is connected to the pre-combustion chamber through the spray hole.

2. The pre-combustion chamber structure according to claim 1, characterized in that: There is a gap between the spark plug and the end of the adapter facing each other; And / or, there is a gap between the fuel injector and the end of the adapter facing each other.

3. The pre-combustion chamber structure according to claim 1, characterized in that: The adapter has a first inner cavity, and the cylinder head also includes a transition portion, the first mounting portion and the second mounting portion are respectively connected to opposite ends of the transition portion, the transition portion has a second inner cavity, and the first inner cavity and the second inner cavity form the pre-combustion chamber.

4. The pre-combustion chamber structure according to claim 3, characterized in that: The wall thickness of the transition portion is less than or equal to the wall thickness of the first mounting portion; And / or, the thickness of the transition portion is less than or equal to the wall thickness of the second mounting portion.

5. The pre-combustion chamber structure according to claim 3, characterized in that: The cross-sectional area of ​​at least a portion of the second inner cavity gradually increases toward the first mounting portion; And / or, the cross-sectional area of ​​the second inner cavity is greater than the cross-sectional area of ​​the first inner cavity.

6. The pre-combustion chamber structure according to claim 1, characterized in that: The adapter is threadedly connected in the third mounting cavity; and / or, the spark plug is threadedly connected in the first mounting cavity; And / or, the injector is threadedly connected in the second mounting cavity.

7. The pre-combustion chamber structure according to claim 1, characterized in that: The adapter is threadedly connected in the third installation cavity. The third installation cavity forms an opening at one end facing the main combustion chamber. The adapter can be installed in the third installation cavity through the opening.

8. The pre-combustion chamber structure according to claim 1, characterized in that: The adapter includes at least one first area and at least one second area, and at least one injection hole is disposed in each of the first area and the second area, wherein: The number of the injection holes located in the first area is different from the number of the injection holes located in the second area; and / or, the inner diameter of the injection hole located in the first area is different from the inner diameter of the injection hole located in the second area; and / or, the spacing between adjacent injection holes in the first region in the circumferential direction of the adapter is different from the spacing between adjacent injection holes in the second region in the circumferential direction of the adapter; And / or, an angle between a center line of the injection hole in the first region and a center line of the adapter is different from an angle between a center line of the injection hole in the second region and a center line of the adapter.

9. The pre-combustion chamber structure according to claim 8, characterized in that: A first combustion zone and a second combustion zone are provided in the main combustion chamber, the mixed gas concentration in the first combustion zone is greater than the mixed gas concentration in the second combustion zone, and the flame jet flow in the first zone is greater than the flame jet flow in the second zone; the adapter is threadedly connected to the third mounting cavity, and the endpoint of the lower end of the external thread of the adapter is aligned with the endpoint of the lower end of the internal thread of the second mounting part, so that the first zone faces the first combustion zone, and the second zone faces the second combustion zone.

10. An engine, characterized in that include: The pre-combustion chamber structure according to any one of claims 1 to 9; The cooling structure is at least wrapped around the outside of the pre-combustion chamber.

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