Engine

Abstract

The invention provides an engine. The engine comprises an air cylinder body, an air cylinder cover and an air intake and exhaust system. The cylinder cover is connected with the cylinder body and forms a combustion chamber with the cylinder cover, the cylinder cover comprises a ventilation channel and a valve guide pipe, the ventilation channel is communicated with the combustion chamber, and the valve guide pipe forms a channel communicated with the ventilation channel; the air inlet and exhaust system comprises an air valve penetrating through the channel, and at least part of the air valve extends into the air duct and controls the air duct to be communicated with or disconnected from the combustion chamber. The air inlet and exhaust system further comprises a valve sealing ring, the valve sealing ring is installed on the air cylinder cover and located at the joint of the air passage and the combustion chamber, the valve sealing ring is suitable for containing at least part of the valve, a cylindrical throat opening is defined by the inner edge of the valve sealing ring, and an included angle larger than 0 degree is formed between the axis of the throat opening and the axis of the passage. Through the arrangement, the air inlet efficiency of the air inlet channel is improved, fuel oil and air are fully mixed, and the combustion efficiency of an engine is higher.

Description

Technical Field

[0001] This application relates to the field of power systems, and more particularly to an engine. Background Technology

[0002] As the power source for vehicles such as cars and motorcycles, the engine drives the piston to reciprocate within the cylinder by igniting the fuel-air mixture in the combustion chamber, which in turn drives the crankshaft to rotate. During engine operation, airflow efficiency is a crucial factor affecting engine efficiency, encompassing both intake and exhaust efficiency.

[0003] In related technologies, a turbine is typically installed at the end of the air intake away from the combustion chamber to improve airflow efficiency through turbocharging. However, the turbine increases the overall size of the engine. Without considering the need for an additional turbocharger, how to increase the engine's airflow efficiency to improve its overall performance has become a pressing technical challenge in the industry. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the purpose of this application is to provide an engine with higher working efficiency.

[0005] To achieve the above objectives, this application adopts the following technical solution:

[0006] An engine includes: a cylinder block, a cylinder head, and an intake and exhaust system; the cylinder head is connected to the cylinder block and forms a combustion chamber with the cylinder head, the cylinder head including a vent passage and a valve guide, the vent passage communicating with the combustion chamber; the intake and exhaust system includes a valve passing through the valve guide, at least a portion of the valve extending into the vent passage and controlling the vent passage to communicate or disconnect from the combustion chamber; the intake and exhaust system further includes a valve sealing ring, the valve sealing ring being mounted on the cylinder head and located at the connection between the vent passage and the combustion chamber, the valve sealing ring being adapted to receive at least a portion of the valve, the inner edge of the valve sealing ring surrounding a cylindrical gill, the axis of the gill forming an angle greater than 0° with the axis of the valve.

[0007] Furthermore, the ventilation duct includes an intake duct capable of supplying a fuel-air mixture to the combustion chamber; the valve guide includes an intake valve guide communicating with the intake duct; the valve includes an intake valve passing through a first channel formed by the intake valve guide; the intake valve is capable of controlling the connection or disconnection between the intake duct and the combustion chamber; the valve sealing ring includes an intake valve sealing ring located at the connection between the intake duct and the combustion chamber, and housing at least a portion of the intake valve; the inner edge of the intake valve sealing ring surrounds a cylindrical intake nozzle; the axis of the intake nozzle forms a first angle ranging from 5° to 15° with the axis of the first channel.

[0008] Furthermore, the ventilation duct includes an exhaust duct capable of discharging exhaust gas from the combustion chamber, the valve guide includes an exhaust valve guide communicating with the exhaust duct, the valve includes an exhaust valve passing through the second channel formed by the exhaust valve guide, the exhaust valve being capable of controlling the connection or disconnection between the exhaust duct and the combustion chamber; the valve sealing ring includes an exhaust valve sealing ring located at the connection between the exhaust duct and the combustion chamber, and housing at least a portion of the exhaust valve, the inner edge of the exhaust valve sealing ring surrounding a cylindrical exhaust nozzle, the axis of the exhaust nozzle forming a second angle with the axis of the second channel, the second angle being smaller than the first angle.

[0009] Furthermore, the range of the second included angle is 0° to 10°.

[0010] Furthermore, the cylinder head includes a splice portion surrounding the intake manifold and connected to the intake valve sealing ring, the splice portion being adapted to house the intake valve sealing ring, the splice portion and the intake valve sealing ring forming an intake vent.

[0011] Furthermore, the intake valve sealing ring is interference-fitted with the splicing part.

[0012] Furthermore, the air intake includes an air intake port located at the end of the air intake away from the combustion chamber. The outer peripheral wall of the air intake includes a first part and a second part, the surface areas of the first part and the second part are basically the same, the first part is closer to the air intake port than the second part, both the first part and the second part are formed by grinding, and the grinding depth of the first part is greater than the grinding depth of the second part.

[0013] Furthermore, the intake and exhaust system also includes a throttle valve, and the cylinder head includes a cylinder head body, a first mounting part, and a second mounting part. The first mounting part and the second mounting part are connected to the cylinder head body, and the first mounting part is located above the second mounting part. The end of the intake manifold away from the combustion chamber is the intake port. The first mounting part and the second mounting part are distributed around the intake port. Both the first mounting part and the second mounting part are tightly connected to the throttle valve and both have an end face that abuts against the throttle valve. The end face of the first mounting part is parallel to the end face of the second mounting part and is not on the same plane.

[0014] Furthermore, in the front-rear direction of the cylinder head, the length of the second mounting part is basically the same as the length of the first mounting part.

[0015] Furthermore, the structures of the first mounting part and the second mounting part are basically the same. Both include a cantilever and a connecting platform. The cantilever is connected to the cylinder head body, and the connecting platform is located at the end of the cantilever away from the cylinder head body and extends towards the front and upper part of the cylinder head.

[0016] This application provides an engine in which the valve sealing ring is installed on the cylinder head and located at the connection between the air passage and the combustion chamber. The inner edge of the valve sealing ring forms a cylindrical gill, so that the axis of the passage where the intake valve is installed forms an angle greater than 0° with the axis of the gill, thereby reducing the large pressure loss generated when the airflow passes through the gill and improving the working efficiency of the engine. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the engine in an embodiment of this application;

[0018] Figure 2 This is a schematic diagram of the cylinder head and intake / exhaust system in the embodiments of this application;

[0019] Figure 3 This is a perspective view of the cylinder head in the embodiment of this application;

[0020] Figure 4 This is a cross-sectional view of the cylinder head in an embodiment of this application;

[0021] Figure 5 In the embodiments of this application Figure 4 Enlarged view of point A;

[0022] Figure 6 In the embodiments of this application Figure 4 Enlarged view of point B;

[0023] Figure 7 This is a schematic diagram of the cylinder head in an embodiment of this application;

[0024] Figure 8 This is a side view of the cylinder head in the embodiment of this application;

[0025] Figure 9 This is a cross-sectional view of the cylinder head and intake / exhaust system in an embodiment of this application;

[0026] Figure 10 In the embodiments of this application Figure 9 Enlarged view of point C;

[0027] Figure 11 This is a schematic diagram of the connection structure in the embodiment of this application. Detailed Implementation

[0028] To enable those skilled in the art to better understand the present application, the technical solutions in specific embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0029] It should be noted that the terms "first," "second," and similar terms used in this application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, "a" or "one," and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. "A plurality" or "several" indicates at least two. Unless otherwise stated, terms such as "front," "back," "left," "right," "lower," and / or "upper" are for illustrative purposes only and are not limited to a location or spatial orientation. Terms such as "comprising" or "including" indicate that the elements or objects preceding "comprising" encompass the elements or objects listed following "comprising" or "including" and their equivalents, and do not exclude 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.

[0030] The singular forms “a,” “the,” and “the” used in this application specification and appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0031] like Figure 1 As shown, this application provides an engine 100, which can be used as a power supply device for vehicles such as automobiles and motorcycles. In the embodiments of this application, the engine 100 is a reciprocating piston internal combustion engine, which can convert the chemical energy of fuel into the mechanical energy of piston movement and output power. The engine 100 includes a housing 10, which constitutes the main frame of the engine 100. The housing 10 includes a cylinder head cover 11, a cylinder head 12, a cylinder block 14, a crankcase 15, and an oil pan 16 connected in sequence. To clearly illustrate the technical solution of this application, the following are also provided: Figure 1 The engine 100 is located in the up-down, left-right, and front-back directions.

[0032] In this embodiment, the engine 100 is a V-type engine. The V-type engine includes a first cylinder head 12a and a second cylinder head 12b arranged one in front of the other. Both the first cylinder head 12a and the second cylinder head 12b are connected to the cylinder block 14, and their structures are basically the same except for their positions and orientations. It should be noted that "basically the same structure" means that the number and shape of their functional components are the same. The situation where some functional components are symmetrical about a specific point for ease of installation and arrangement also falls under the aforementioned shape consistency.

[0033] like Figure 1 and Figure 2As shown, the engine 100 also includes an intake and exhaust system 20 mounted on the cylinder head 12. The intake and exhaust system 20 can deliver air into the cylinder head 12, mix the air with atomized fuel to form a fuel mixture, and also discharge the exhaust gas formed after the combustion of the fuel mixture from the cylinder head 12.

[0034] The intake and exhaust system 20 includes an intake system 21, which includes an air filter (not shown), an intake manifold 211, and a throttle valve 212. The air filter is used to absorb and filter air. The intake manifold 211 connects the air filter and the cylinder head 12, and it can receive and deliver air filtered by the air filter.

[0035] like Figure 2 and Figure 3 As shown, in one implementation, the cylinder head 12 and the cylinder block 14 form a combustion chamber 141 for the reciprocating motion of the piston mechanism. The cylinder head 12 includes a ventilation passage 121 and a valve guide 122. The ventilation passage 121 communicates with the combustion chamber 141, and the valve guide 122 forms a channel 1221 communicating with the ventilation passage 121. The intake and exhaust system 20 also includes a valve 22 passing through the valve guide 122. At least a portion of the valve 22 extends into the ventilation passage 121 and controls the connection or disconnection between the ventilation passage 121 and the combustion chamber 141.

[0036] Specifically, the intake and exhaust system 20 also includes a valve sealing ring 23, which is installed on the cylinder head 12 and located at the connection between the air passage 121 and the combustion chamber 141. The valve sealing ring 23 is adapted to accommodate at least part of the valve 22. The inner edge of the valve 22 is sealed to form a cylindrical gill 231, and the axis of the gill 231 forms an angle greater than 0° with the axis of the valve 22.

[0037] By setting the above, the axis of the channel 1221 where the valve 22 is installed forms an angle greater than 0° with the axis of the nozzle 231, thereby reducing the large pressure loss when the airflow passes through the nozzle 231 and improving the working efficiency of the engine 100.

[0038] like Figure 4 As shown, in one implementation, the ventilation duct 121 includes an intake duct 1211 and an exhaust duct 1212 capable of delivering a fuel-air mixture into the combustion chamber 141. The number of intake ducts 1211 and the number of exhaust ducts 1212 are the same, and both have at least one.

[0039] Each intake manifold 211 corresponds to an intake port 1211, and the air output from the air filter is evenly distributed to different intake ports 1211 through the intake manifold 211. A throttle valve 212 is mounted on the cylinder head 12, connecting the intake manifold 211 and the intake ports 1211. By adjusting the opening angle of the throttle valve 212, the amount of air entering the intake ports 1211 is increased or decreased. The intake ports 1211 have opposing intake ports 1211a and outlet ports 1211b. Intake port 1211a is connected to the throttle valve 212 and is used to receive the air supplied by the throttle valve 212. Outlet port 1211b is connected to the combustion chamber 141 and is used to deliver the fuel-air mixture from the intake ports 1211 to the combustion chamber 141. The exhaust duct 1212 has an intake end 1212a and an exhaust end 1212b, with the intake end 1212a communicating with the combustion chamber 141. When the engine 100 is a turbocharged engine, the exhaust end 1212b communicates with a turbine (not shown) mounted on the cylinder head 12. When the engine 100 is a naturally aspirated engine, the exhaust end 1212b communicates with an exhaust manifold (not shown) to discharge exhaust gases from the engine 100 through the exhaust manifold.

[0040] Valve guide 122 includes an intake valve guide 1222 communicating with the intake passage 1211 and an exhaust valve guide 1223 communicating with the exhaust passage 1212. Valve 22 includes an intake valve 221 and an exhaust valve 222. The intake valve 221 passes through a first channel 1221a formed by the intake valve guide 1222, and the intake valve 221 can control the connection or disconnection between the intake passage 1211 and the combustion chamber 141. The exhaust valve 222 passes through a second channel 1221b formed by the exhaust valve guide 1223, and the exhaust valve 222 can control the connection or disconnection between the exhaust passage 1212 and the combustion chamber 141.

[0041] like Figure 5 and Figure 6As shown, the valve sealing ring 23 includes an intake valve sealing ring 232 and an exhaust valve sealing ring 233. The intake valve sealing ring 232 is located at the connection between the intake duct 1211 and the combustion chamber 141, and houses at least a portion of the intake valve 221. The inner edge of the intake valve sealing ring 232 surrounds a cylindrical intake manifold 2311. The intake manifold 2311 serves as a transition structure connecting the intake duct 1211 and the combustion chamber 141. Air entering the intake duct 1211 changes its flow direction through the intake manifold 2311, causing a deflection in the airflow direction to reduce pressure loss generated during airflow within the intake duct 1211. The exhaust valve sealing ring 233 is located at the connection between the exhaust duct 1212 and the combustion chamber 141, and houses at least a portion of the exhaust valve 222. The inner edge of the exhaust valve sealing ring 233 surrounds a cylindrical exhaust manifold 2312. The exhaust port 2312 serves as a transitional structure connecting the exhaust duct 1212 and the combustion chamber 141. The air entering the exhaust duct 1212 changes its flow direction through the exhaust port 2312, causing the airflow direction to shift, thereby reducing the pressure loss generated when the exhaust gas flows through the exhaust port 2312 and improving exhaust efficiency.

[0042] like Figures 4 to 6 As shown, in one implementation, the axis of the intake vent 2311 forms a first angle α with the axis of the first channel 1221a, and the axis of the exhaust vent 2312 forms a second angle β with the axis of the second channel 1221b, the second angle β being smaller than the first angle α.

[0043] As one implementation, the first included angle α ranges from 5° to 15°, and the second included angle β ranges from 0° to 10°. Further, the first included angle α ranges from 7° to 12°, and the second included angle β ranges from 3° to 8°. More preferably, the first included angle α is 10°, and the second included angle β is 6°.

[0044] It should be noted that if the first included angle α is too small, it will result in a large angle between the intake manifold 2311 and the intake duct 1211, leading to a significant pressure loss at the junction of the intake duct 1211 and the intake manifold 2311. If the first included angle α is too large, this design of the intake duct 1211 and intake manifold 2311 will excessively encroach on the space of the exhaust duct 1212 in the cylinder head 12, affecting the exhaust efficiency of the engine 100. If the range of the second included angle β is too small, the pressure loss generated when the exhaust gas passes through the exhaust manifold 2312 will be significant, affecting the exhaust efficiency of the exhaust gas passing through the exhaust duct 1212. If the range of the second included angle β is too large, with the length of the intake duct 1211 remaining constant, a longer exhaust duct 1212 is required to meet the exhaust requirements of the engine 100, resulting in an increase in the size and weight of the engine 100.

[0045] The above configuration makes the junction between the intake duct 1211 and the intake nozzle 2311 smoother, reducing the pressure loss generated when the airflow passes through the junction of the intake duct 1211 and the intake nozzle 2311. Furthermore, while ensuring the compactness of the engine 100, it reduces the pressure loss of the exhaust gas flow, thus ensuring the exhaust performance of the engine 100.

[0046] In one implementation, the cylinder head 12 includes a splice portion 123 surrounding the intake manifold 1211 and connected to the intake valve sealing ring 232. The splice portion 123 is adapted to accommodate the intake valve sealing ring 232, and the intake valve sealing ring 232 is interference-fitted with the splice portion 123. The splice portion 123 and the intake valve sealing ring 232 surround to form an intake manifold 2311, thereby extending the axial length of the intake manifold 2311 and reducing the pressure loss of airflow passing through the intake manifold 2311.

[0047] Specifically, the splicing part 123 forms a first limiting groove 1231, the inner diameter of which is larger than the inner diameter of the air intake duct 1211. The inner edge of the air intake valve sealing ring 232 is connected to the inner wall of the air intake duct 1211, and a smooth curved surface is formed at the junction of the two.

[0048] In this embodiment, the cylinder head 12 forms a second limiting groove 124 at the exhaust end 1212b of the exhaust passage 1212, and the exhaust valve sealing ring 233 is disposed in the second limiting groove 124 and is interference-fitted with the cylinder head 12.

[0049] As one implementation, the outer peripheral wall of the intake vent 2311 includes a first part 2311a and a second part 2311b. The surface areas of the first part 2311a and the second part 2311b are basically the same. The first part 2311a is closer to the intake port 1211a than the second part 2311b. Both the first part 2311a and the second part 2311b are formed by grinding. The grinding depth of the first part 2311a is greater than the grinding depth of the second part 2311b. Through the above arrangement, the junction between the intake duct 1211 and the intake vent 2311 is made smoother, reducing the pressure loss generated when the airflow passes through the junction of the intake duct 1211 and the intake vent 2311. In addition, while minimizing interference with the exhaust duct 1212, the flow cross-sectional area of ​​the intake duct 1211 is further increased, thereby increasing the intake volume of the intake duct 1211.

[0050] like Figure 7As shown, in one implementation, the cylinder head 12 includes multiple mounting portions 129, each of which is tightly connected to the throttle valve 212 via fasteners, and each mounting portion 129 has an end face that abuts against the throttle valve 212. The multiple mounting portions 129 include a first mounting portion 129a and a second mounting portion 129b. The cylinder head 12 includes a cylinder head body 126, and the first mounting portion 129a and the second mounting portion 129b are connected to the cylinder head body 126, with the first mounting portion 129a located above the second mounting portion 129b. The intake manifold 121 has an intake port for receiving air, and the first mounting portion 129a and the second mounting portion 129b are arranged around the intake port. Both the first mounting portion 129a and the second mounting portion 129b have an end face that abuts against the throttle valve 212. The end face of the first mounting portion 129a is parallel to the end face of the second mounting portion 129b, but they are not on the same plane.

[0051] To clearly illustrate the technical solution of this application, the following are also provided: Figure 7 The cylinder head 12 shown is positioned vertically, horizontally, and front-back.

[0052] Specifically, in the front-rear direction of the cylinder head 12, the length of the second mounting portion 129b is substantially the same as the length of the first mounting portion 129a. It should be noted that, due to tolerances inherent in the manufacturing process of the cylinder head 12, these tolerances may be caused by deformation during molding, material handling, or assembly. Therefore, the statement in this application that the lengths are substantially the same means that, after considering the tolerances present in actual conditions, the actual deviation between the length of the second mounting portion 129b and the length of the first mounting portion 129a does not exceed a 5% tolerance.

[0053] In this embodiment of the application, the cylinder head 12 includes a pair of first mounting portions 129a, which are distributed along the left and right directions of the cylinder head 12. The cylinder head 12 has a pair of intake passages 1211, which are located between the pair of first mounting portions 129a, and a second mounting portion 129b is located between the pair of intake passages 1211.

[0054] The above-mentioned configuration makes the stress on each mounting part 129 more uniform, resulting in higher overall structural strength and better modal properties of the cylinder head 12, and makes the overall structure of the cylinder head 12 more compact, which helps to achieve lightweight design of the engine 100.

[0055] like Figure 8 As shown, in one implementation, any one of the multiple mounting parts 129 includes a cantilever 1293 and a connecting platform 1294. One end of the cantilever 1293 is connected to the main body of the cylinder head 12, and the other end is connected to the connecting platform 1294. The connecting platform 1294 extends towards the front and upper part of the cylinder head 12.

[0056] Specifically, the extension direction of the cantilever 1293 forms an angle γ with the extension direction of the connecting platform 1294, and the angle γ ranges from 90° to 180°.

[0057] The above settings facilitate the installation of the throttle valve 212 and reduce intake resistance.

[0058] like Figures 9 to 11 As shown, in one implementation, the intake system 21 also includes a connecting structure 215 connecting the throttle valve 212 and the cylinder head 12. The connecting structure 215 is annular and arranged around the intake port of the intake manifold 1211. The throttle valve 212 is connected to the cylinder head 12 through the connecting structure 215. The throttle valve 212 has an end 2121 connected to the cylinder head 12. The connecting structure 215 is fitted onto the end 2121 of the throttle valve 212. The cylinder head 12 forms a fixing groove 125, which surrounds the intake port of the intake manifold 1211. The connecting structure 215 is interference-fitted into the fixing groove 125.

[0059] The above settings reduce the difficulty of installing the throttle body 212, and no fasteners such as bolts and pins are needed when installing the throttle body 212, making the structure of the connection between the throttle body 212 and the cylinder head 12 more compact, and making the overall weight of the engine 100 lighter.

[0060] Furthermore, the inner edge of the connecting structure 215 forms a continuous curved surface with the inner wall of the intake duct 1211 to avoid pressure loss when air enters the intake duct 1211.

[0061] Specifically, the connecting structure 215 is made of rubber and has a metal part 2155 inside, thereby improving the structural strength of the connecting structure 215 and extending its service life.

[0062] In one implementation, the connecting structure 215 includes a main body 2151 and a protrusion 2152. The main body 2151 forms the main frame of the connecting structure 215, and the protrusion 2152 is disposed on the outer edge of the main body 2151. When the connecting structure 215 is installed in the fixing groove 125, the protrusion 2152 surrounding the outer edge of the main body 2151 deforms to increase the stability and sealing of the connecting structure 215 installed in the fixing groove 125.

[0063] Furthermore, the connecting structure 215 also includes an abutment portion 2153, which is disposed on the inner edge of the main body portion 2151. The abutment portion 2153 abuts against the throttle valve 212 in the mounting direction of the throttle valve 212 to avoid direct contact between the throttle valve 212 and the cylinder head 12. Since the engine 100 will vibrate when it is working, the above arrangement can reduce the hard friction between the throttle valve 212 and the cylinder head 12.

[0064] In this structure, part of the metal part 2155 is located inside the abutment part 2153, and another part of the metal part 2155 is located inside the main body part 2151, thereby improving the structural strength of the connecting structure 215 and extending its service life.

[0065] Optionally, the connecting structure 215 includes an abutment portion 2153 and a limiting portion 2154 connected to the abutment portion 2153. The abutment portion 2153 is arranged on the inner edge of the main body portion 2151, and the limiting portion 2154 is disposed on the inner edge of the abutment portion 2153. The limiting portion 2154 extends from the abutment portion 2153 toward the throttle valve 212. When the throttle valve 212 is connected to the connecting structure 215, the throttle valve 212 abuts against the limiting portion 2154, thereby forming a buffer gap between the abutment portion 2153 and the throttle valve 212. This avoids direct contact between the throttle valve 212 and the abutment portion 2153, reducing wear on the end 2121 of the throttle valve 212.

[0066] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. An engine, comprising: Cylinder block; A cylinder head, which is connected to the cylinder block and forms a combustion chamber with the cylinder head, the cylinder head including a vent passage and a valve guide, the vent passage communicating with the combustion chamber; An intake and exhaust system, comprising a valve passing through the valve guide, at least a portion of the valve extending into the air passage and controlling the air passage to communicate with or disconnect from the combustion chamber; The characteristic feature is that the intake and exhaust system further includes a valve sealing ring, which is installed on the cylinder head and located at the connection between the air passage and the combustion chamber. The valve sealing ring houses at least a portion of the valve, and the inner edge of the valve sealing ring surrounds a cylindrical nozzle. The axis of the nozzle forms an angle greater than 0° with the axis of the valve.

2. The engine according to claim 1, characterized in that, The ventilation duct includes an intake duct capable of supplying a fuel-air mixture to the combustion chamber. The valve guide includes an intake valve guide forming a first channel communicating with the intake duct. The valve includes an intake valve passing through the first channel, and the intake valve is capable of controlling the connection or disconnection between the intake duct and the combustion chamber. The valve sealing ring includes an intake valve sealing ring located at the connection between the intake duct and the combustion chamber, and houses at least a portion of the intake valve. The inner edge of the intake valve sealing ring surrounds a cylindrical intake nozzle, and the axis of the intake nozzle forms a first angle ranging from 5° to 15° with the axis of the intake valve.

3. The engine according to claim 2, characterized in that, The ventilation duct includes an exhaust duct capable of discharging exhaust gases from the combustion chamber. The valve guide includes an exhaust valve guide, which forms a second channel communicating with the exhaust duct. The valve includes an exhaust valve passing through the second channel, and the exhaust valve is capable of controlling the connection or disconnection between the exhaust duct and the combustion chamber. The valve sealing ring includes an exhaust valve sealing ring located at the connection between the exhaust duct and the combustion chamber, and houses at least a portion of the exhaust valve. The inner edge of the exhaust valve sealing ring surrounds a cylindrical exhaust nozzle, and the axis of the exhaust nozzle forms a second angle with the axis of the exhaust valve, the second angle being smaller than the first angle.

4. The engine according to claim 3, characterized in that, The second included angle ranges from 0° to 10°.

5. The engine according to claim 2, characterized in that, The cylinder head includes a splice portion surrounding the intake manifold and connected to the intake valve sealing ring. The splice portion is adapted to receive the intake valve sealing ring, and the splice portion and the intake valve sealing ring surround the intake vent.

6. The engine according to claim 5, characterized in that, The intake valve sealing ring is interference-fitted with the splicing part.

7. The engine according to claim 2, characterized in that, The air intake duct includes an air intake port located at one end of the air intake duct away from the combustion chamber. The outer peripheral wall of the air intake port includes a first part and a second part. The surface areas of the first part and the second part are basically the same. The first part is closer to the air intake port than the second part. Both the first part and the second part are formed by grinding. The grinding depth of the first part is greater than the grinding depth of the second part.

8. The engine according to claim 2, characterized in that, The intake and exhaust system also includes a throttle valve. The cylinder head includes a cylinder head body, a first mounting portion, and a second mounting portion. The first mounting portion and the second mounting portion are connected to the cylinder head body, and the first mounting portion is located above the second mounting portion. The end of the intake manifold away from the combustion chamber is the intake port. The first mounting portion and the second mounting portion are distributed around the intake port. Both the first mounting portion and the second mounting portion are tightly connected to the throttle valve and both have an end face that abuts against the throttle valve. The end face of the first mounting portion is parallel to the end face of the second mounting portion and is not on the same plane.

9. The engine according to claim 8, characterized in that, In the front-rear direction of the cylinder head, the length of the second mounting portion is substantially the same as the length of the first mounting portion.

10. The engine according to claim 8, characterized in that, The first mounting part and the second mounting part have basically the same structure. Both include a cantilever and a connecting platform. The cantilever is connected to the cylinder head body, and the connecting platform is located at the end of the cantilever away from the cylinder head body and extends towards the front and upper part of the cylinder head.

Images