1. A cylinder cover comprises an air inlet throat and an exhaust throat and is characterized in that an air inlet chamfer is arranged at a bottom hole of the air inlet throat, an exhaust chamfer is arranged at a bottom hole of the exhaust throat, the center of the air inlet chamfer deviates a first preset distance towards the direction of the exhaust throat relative to the center of the air inlet throat, and a communicating groove communicated between the air inlet chamfer and the exhaust chamfer is formed in the bottom surface of the cylinder cover.

2. The cylinder head of claim 1, wherein a center of the exhaust chamfer is offset a second predetermined distance toward the intake throat relative to a center of the exhaust throat.

3. The cylinder head of claim 2, wherein a center of the intake chamfer and/or a center of the exhaust chamfer is located on a center line of the intake throat and the exhaust throat.

4. The cylinder head according to claim 2, characterized in that the first preset distance is greater than 0 and equal to or less than 0.3 times the diameter of the exhaust throat and/or the second preset distance is greater than 0 and equal to or less than 0.3 times the diameter of the intake throat.

5. The cylinder head of claim 1, wherein the communication groove is symmetrical with respect to a line connecting centers of the intake throat and the exhaust throat.

6. The cylinder head according to claim 5, wherein both side walls of the communication groove extend in a straight line.

7. The cylinder head according to claim 6, wherein both side walls of the communication groove extend in directions parallel to a central line connecting the intake throat and the exhaust throat.

8. The cylinder head according to claim 1, wherein the connecting portions of the two side walls of the communicating groove and the intake chamfer and the exhaust chamfer are both smooth transition surface structures.

9. The cylinder head according to claim 1, wherein a width of the communication groove is greater than 0 and equal to or less than a diameter of the exhaust throat.

10. The cylinder head of claim 1, wherein the intake chamfer and/or the exhaust chamfer is a rounded rotary chamfer.

11. A cylinder head according to claim 10, characterized in that the longitudinal section of the inlet chamfer and/or the longitudinal section of the outlet chamfer is a straight line or a curved line.

12. The cylinder head according to claim 10, wherein a longitudinal section of the intake chamfer and/or a longitudinal section of the exhaust chamfer is a curve that is convex toward an inside of the cylinder.

13. A cylinder head according to claim 10, characterized in that the centre line of revolution of the inlet chamfer and/or the exhaust chamfer is parallel with respect to the axis of the inlet throat.

14. The cylinder head according to claim 10, wherein a turning center line of the intake chamfer is arranged obliquely to an axis of the intake throat and a lower end opening of the intake chamfer is arranged toward the exhaust throat, and/or a turning center line of the exhaust chamfer is arranged obliquely to an axis of the exhaust throat and a lower end opening of the exhaust chamfer is arranged toward the intake throat.

15. The cylinder head of claim 14, wherein the angle of inclination of the centerline of revolution of the intake chamfer with respect to the axis of the intake throat is 30 ° or less, and the angle of inclination of the centerline of revolution of the exhaust chamfer with respect to the axis of the exhaust throat is 30 ° or less.

16. The cylinder head of claim 1, wherein the number of intake throats is one or two or three.

17. The cylinder head of claim 1, comprising a first intake throat and a second intake throat, the first intake throat being spaced from a cylinder head intake port by a distance less than the second intake throat being spaced from the cylinder head intake port, a first intake valve seat ring being disposed in the first intake throat, a second intake valve seat ring being disposed in the second intake throat, the first intake valve seat ring being spaced from the bottom surface of the cylinder head by a height greater than the second intake valve seat ring.

18. The cylinder head of claim 17, wherein a difference in height of the first and second intake valve seats is equal to or less than 0.2 times an intake valve diameter.

19. The cylinder head of claim 1, including at least two intake ports, and wherein each of the intake ports is spaced apart.

20. The cylinder head of claim 1, wherein the number of intake throats is at least two, and the intake chamfers of at least two of the intake throats are different.

21. The cylinder head of claim 1, including a head inlet port disposed at a side or top or bottom surface of the cylinder head.

22. A gas engine, characterized by comprising a cylinder head according to any one of claims 1 to 21.

Background

With the development of gas engine technology, more and more gas engines are transformed on the basis of diesel engines at present. In the case of a diesel engine, the combustion mode is diffusion combustion, and a certain degree of swirl helps the oil bundles to mix with air, thereby improving the combustion process, so that an air inlet passage in the cylinder head of the engine is required to organize the air flow to generate a sufficient swirl ratio during the intake process. Wherein, the vortex refers to the gas rotational flow movement organized around the cylinder axial direction.

However, the combustion mode of the gas engine is premixed combustion, the requirement on the strength of vortex is not high, and small-scale turbulent motion is needed to form a flame wrinkle surface, so that the flame propagation speed is increased, and the heat efficiency is improved, wherein the turbulent motion refers to small rotational flow which is generated in a flow field when the air flow speed is high and has unfixed directions, and is different from laminar motion. For a gas engine, the strength of the vortex does not need to be increased, and the increase of the tumble strength in the cylinder can be beneficial to forming turbulence at the end of compression and generating enough turbulent kinetic energy when the piston moves up to the top dead center, so that the aim of optimizing combustion is fulfilled. Wherein, the tumble refers to the gas rotational flow motion of which the rotation central axis is vertical to the axial direction of the cylinder sleeve.

Therefore, for the existing gas engine cylinder cover which is designed by integrally modifying the diesel engine cylinder cover, tumble flow required by the gas engine is difficult to generate in the cylinder.

Therefore, how to improve the tumble strength in the cylinder of the gas engine is a technical problem that needs to be solved by those skilled in the art.

Disclosure of Invention

In view of the above, the present invention provides a cylinder head, which is improved in structure based on the existing diesel engine, so that the gas entering the cylinder generates the tumble motion required by the gas engine, and further, the thermal efficiency of the gas engine is improved. Another object of the present invention is to provide a gas engine comprising the above cylinder head.

In order to achieve the purpose, the invention provides the following technical scheme:

a cylinder cover comprises an air inlet throat and an exhaust throat, wherein an air inlet chamfer is arranged at a bottom hole of the air inlet throat, an exhaust chamfer is arranged at a bottom hole of the exhaust throat, the center of the air inlet chamfer is deviated by a first preset distance towards the direction of the exhaust throat relative to the center of the air inlet throat, and a communicating groove communicated between the air inlet chamfer and the exhaust chamfer is formed in the bottom surface of the cylinder cover.

Preferably, the center of the exhaust chamfer is offset by a second preset distance towards the intake throat relative to the center of the exhaust throat.

Preferably, the center of the inlet chamfer and/or the center of the outlet chamfer are located on the central connecting line of the inlet throat and the outlet throat.

Preferably, the first predetermined distance is greater than 0 and equal to or less than 0.3 times the diameter of the exhaust throat, and/or the second predetermined distance is greater than 0 and equal to or less than 0.3 times the diameter of the intake throat.

Preferably, the communicating groove is in a symmetrical structure relative to a central connecting line of the air inlet throat and the exhaust throat.

Preferably, both side walls of the communication groove extend along straight lines.

Preferably, the extending directions of the two side walls of the communicating groove are parallel to the central connecting line of the air inlet throat and the air outlet throat.

Preferably, the connection parts of the two side walls of the communication groove and the air inlet chamfer and the air outlet chamfer are both smooth transition surface structures.

Preferably, the width of the communication groove is greater than 0 and equal to or less than the diameter of the exhaust throat.

Preferably, the intake chamfer and/or the exhaust chamfer is a rounded rotary chamfer.

Preferably, the longitudinal section of the inlet chamfer and/or the longitudinal section of the outlet chamfer is a straight line or a curved line.

Preferably, a longitudinal section of the intake chamfer and/or a longitudinal section of the exhaust chamfer is a curve protruding toward the cylinder interior.

Preferably, the centre line of revolution of the inlet chamfer and/or the exhaust chamfer is parallel to the axis of the inlet throat.

Preferably, the centre of gyration of the inlet chamfer is arranged obliquely with respect to the axis of the inlet throat and the lower end opening of the inlet chamfer is arranged towards the exhaust throat, and/or the centre of gyration of the exhaust chamfer is arranged obliquely with respect to the axis of the exhaust throat and the lower end opening of the exhaust chamfer is arranged towards the inlet throat.

Preferably, the inclination angle of the revolution center line of the air inlet chamfer relative to the axis of the air inlet throat is less than or equal to 30 degrees, and the inclination angle of the revolution center line of the exhaust chamfer relative to the axis of the exhaust throat is less than or equal to 30 degrees.

Preferably, the number of the air inlet throats is one or two or three.

Preferably, the cylinder cover comprises a first air inlet throat and a second air inlet throat, the distance between the first air inlet throat and an air inlet of a cylinder cover is smaller than the distance between the second air inlet throat and an air inlet of the cylinder cover, a first air inlet valve seat ring is arranged in the first air inlet throat, a second air inlet valve seat ring is arranged in the second air inlet throat, and the height from the first air inlet valve seat ring to the bottom surface of the cylinder cover is larger than the height from the second air inlet valve seat ring to the bottom surface of the cylinder cover.

Preferably, the difference in height between the first intake valve seat insert and the second intake valve seat insert is equal to or less than 0.2 times the intake valve diameter.

Preferably, at least two air inlets are included, and each air inlet is arranged separately.

Preferably, the number of the air inlet throats is at least two, and the air inlet chamfers of at least two air inlet throats are different.

Preferably, a cylinder head intake port is included, arranged at a side or top or bottom surface of the cylinder head.

The cylinder cover comprises an air inlet throat and an exhaust throat, wherein an air inlet chamfer is arranged at the bottom hole of the air inlet throat, an exhaust chamfer is arranged at the bottom hole of the exhaust throat, the center of the air inlet chamfer deviates a first preset distance towards the exhaust throat relative to the center of the air inlet throat, and a communication groove communicated between the air inlet chamfer and the exhaust chamfer is formed in the bottom surface of the cylinder cover.

The working principle of the invention is as follows:

when an engine cylinder inhales air, an inlet valve is opened, inlet airflow sequentially flows through an air inlet channel, the inlet valve, an inlet valve seat ring and an inlet chamfer and then enters the cylinder, the inlet chamfer has an obvious flow guiding effect, and meanwhile, the inlet chamfer is designed to be deviated towards the direction of an exhaust throat, so that the width of a gap close to one side of the exhaust throat is larger, most of the inlet airflow enters the cylinder from the gap close to one side of the exhaust throat, the airflow far away from one side of the exhaust throat is reduced, and airflow on the two sides can more easily form large-scale tumble motion after entering the cylinder. Meanwhile, the air inlet chamfer and the air outlet chamfer are communicated through the communicating groove, and the air flow close to one side of the air outlet throat can be further guided to the air outlet side, so that effective tumble flow is formed in the cylinder.

Therefore, the invention has the following beneficial effects:

1) on the basis of the structure of the existing diesel engine, the eccentric chamfer is arranged at the air inlet throat, so that the effective flow guide of the air inlet flow is realized, and the tumble strength is favorably enhanced;

2) in the preferred scheme of the invention, the exhaust chamfer is arranged in a manner of offsetting towards the direction of the air inlet throat, so that the exhaust circulation capacity can be further enhanced, and the pumping loss is reduced;

3) the communicating groove is adopted to communicate the chamfers of the air inlet side and the air outlet side, and the air flow passing through the vicinity of the spark plug can be further disturbed by the communicating groove in the compression process to form more turbulence, so that the turbulent kinetic energy near the spark plug is greatly increased, the flame propagation speed is accelerated, and the heat efficiency of the gas engine is further improved.

The invention also provides a gas engine comprising the cylinder cover. The derivation process of the beneficial effects generated by the gas engine is substantially similar to the derivation process of the beneficial effects brought by the cylinder cover, and therefore, the description is omitted.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic view of the connection between an intake chamfer and an exhaust chamfer in an embodiment of the present invention;

FIG. 2 is a schematic view of the inclined arrangement of the center line of gyration of the air intake chamfer in an exemplary embodiment of the invention;

FIG. 3 is a schematic view of an intake airflow flowing from an intake throat to an exhaust throat in an embodiment of the present invention;

FIG. 4 is a schematic illustration of two intake valve races disposed at different heights in an exemplary embodiment of the invention;

FIG. 5 is a schematic diagram illustrating an arrangement of two intake throats and a cylinder head intake port at different intervals in an embodiment of the present invention.

The meaning of the various reference numerals in figures 1 to 5 is as follows:

1-air inlet throat, 2-air outlet throat, 3-air inlet chamfer, 4-air outlet chamfer, 5-air inlet throat center, 6-air outlet throat center, 7-air inlet chamfer center, 8-air outlet chamfer center, 9-communicating groove, 10-air inlet valve seat ring, 11-air inlet throat axis, 12-air inlet chamfer gyration center line, 13-first air inlet valve seat ring, 14-second air inlet valve seat ring, 15-first air inlet channel, 16-second air inlet channel, 17-cylinder cover bottom surface, 18-cylinder cover air inlet, 19-first air inlet throat, 20-second air inlet throat and 21-air inlet outlet throat center connecting line.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1 to 5, fig. 1 is a schematic structural view illustrating a communication between an intake chamfer and an exhaust chamfer according to an embodiment of the present invention; FIG. 2 is a schematic view of the inclined arrangement of the center line of gyration of the air intake chamfer in an exemplary embodiment of the invention; FIG. 3 is a schematic view of an intake airflow flowing from an intake throat to an exhaust throat in an embodiment of the present invention; FIG. 4 is a schematic illustration of two intake valve races disposed at different heights in an exemplary embodiment of the invention; FIG. 5 is a schematic diagram illustrating an arrangement of two intake throats and a cylinder head intake port at different intervals in an embodiment of the present invention.

The invention provides a cylinder cover, which comprises an air inlet throat 1 and an exhaust throat 2 of the existing diesel engine, wherein the bottom hole of the air inlet throat 1 is provided with an air inlet chamfer 3, the bottom hole of the exhaust throat 2 is provided with an exhaust chamfer 4, the center (the center 7 of the air inlet chamfer) of the air inlet chamfer 3 is deviated by a first preset distance L1 towards the direction of the exhaust throat 2 relative to the center (the center 5 of the air inlet throat) of the air inlet throat 1, and the bottom surface 17 of the cylinder cover is provided with a communicating groove 9 communicated between the air inlet chamfer 3 and the exhaust chamfer 4.

The working principle of the invention is as follows:

when an engine cylinder inhales air, an inlet valve is opened, inlet airflow sequentially flows through an air inlet channel, the inlet valve, an inlet valve seat ring and an inlet chamfer 3 and then enters the cylinder, the inlet chamfer 3 has an obvious flow guiding effect, and meanwhile, the inlet chamfer 3 is designed to be deviated towards the direction of an exhaust throat opening 2, so that the width of a gap close to one side of the exhaust throat opening 2 is larger, most of the inlet airflow enters the cylinder from the gap close to one side of the exhaust throat opening 2, the airflow far away from one side of the exhaust throat opening 2 is reduced, and the airflow on the two sides can more easily form large-scale tumble motion after entering the cylinder. Meanwhile, the air inlet chamfer 3 is communicated with the air outlet chamfer 4 through the communicating groove 9, so that the air flow close to one side of the air outlet throat 2 can be further guided to the air outlet side, and effective tumble flow is formed in the cylinder. The direction of the intake airflow from the intake throat 2 to the exhaust throat 2 is shown by the arrows in fig. 3.

Therefore, on the basis of the existing diesel engine, the eccentric chamfers are arranged on the air inlet throat 1 and the communicating grooves 9 are adopted to communicate the chamfers on the air inlet side and the air outlet side, so that the effective flow guide of air inlet flow is realized, the tumble strength is favorably enhanced, the turbulent flow is favorably formed in the last stage of compression, and the heat efficiency of the gas engine is improved.

It should be noted that the exhaust chamfer 4 of the present invention may be designed to be concentric with the exhaust throat 2, or may be eccentrically arranged similarly to the intake chamfer 3. Preferably, the center of the exhaust chamfer 4 (exhaust chamfer center 8) is offset in the direction of the intake throat 1 by a second predetermined distance L2 with respect to the center of the exhaust throat 2 (exhaust throat center 6). So set up, can make the water conservancy diversion face between air intake chamfer 3 and the exhaust chamfer 4 further enlarge to can guide more gas to flow along the direction of air intake throat 1 to exhaust throat 2, be favorable to strengthening the tumble motion. Meanwhile, the exhaust chamfer 4 which is eccentrically arranged is arranged, so that the exhaust circulation capacity can be further enhanced, and the pumping loss is reduced.

Preferably, the inlet chamfer center 7 and/or the exhaust chamfer center 8 is located on the line connecting the inlet throat center 5 and the exhaust throat center 6 (inlet exhaust throat center line 21). So set up, not only be convenient for process eccentric chamfer characteristic, but also can guide the air current that admits air more effectively, reduce gaseous kinetic energy loss.

Preferably, the first preset distance L1 is greater than 0 and equal to or less than 0.3 times the diameter D2 of the exhaust throat 2, and specifically, the first preset distance L1 may be 0.1 times, or 0.2 times, or 0.3 times the diameter D2 of the exhaust throat 2. And/or the second preset distance L2 is greater than 0 and equal to or less than 0.3 times the diameter D1 of the intake throat 1, specifically, the second preset distance L2 may be 0.1 times, or 0.2 times, or 0.3 times the diameter D1 of the intake throat 1. In the practical application process, corresponding design parameters can be selected according to specific models.

It should be noted that the communicating groove 9 in the present invention is located between the inlet chamfer 3 and the outlet chamfer 4, and is mainly used for guiding the airflow from the inlet throat 1 to the outlet throat 2 side, and preferably, the communicating groove 9 is symmetrical with respect to the inlet and outlet throat center connecting line 21.

Further preferably, both side walls of the communication groove 9 extend along straight lines, and thus, the communication groove 9 may be specifically processed into a straight groove or a trapezoidal groove. Of course, the side wall of the communication groove 9 may also extend along a curve such as an arc line, an asymptote line or a hyperbola, and will not be described herein.

Further preferably, the extending directions of both side walls of the communicating groove 9 are parallel to the intake and exhaust throat center connecting line 21, that is, the communicating groove 9 is preferably processed into a straight groove structure.

Preferably, the joints of the two side walls of the communication groove 9 and the air inlet chamfer 3 and the air outlet chamfer 4 are all smooth transition surface structures. With this arrangement, the loss of kinetic energy when the air flow passes through the communication groove 9 can be reduced.

Preferably, the width H of the communication groove 9 is greater than 0 and equal to or less than the diameter D2 of the exhaust throat 2, specifically, the width H of the communication groove 9 may be 0.1 times or 0.2 times or 0.3 times or 0.4 times or 0.5 times or 0.6 times or 0.7 times or 0.8 times or 0.9 times or 1 times the diameter D2 of the exhaust throat 2. In the practical application process, corresponding design parameters can be selected according to specific models.

The communicating groove 9 is adopted to communicate the chamfers of the air inlet side and the air outlet side, and in the compression process, the air flow passing through the vicinity of the spark plug can be further disturbed through the structure of the communicating groove 9 to form more turbulence, so that the turbulent kinetic energy near the spark plug is greatly increased, the flame propagation speed is accelerated, and the heat efficiency of the gas engine is further improved.

In the present invention, the profiles of the intake chamfer 3 and the exhaust chamfer 4 on the cylinder head bottom surface 17 may be circular or non-circular, that is, both the intake chamfer 3 and the exhaust chamfer 4 may be designed as circular rotary chamfer structures, or as non-circular chamfer structures, such as elliptical chamfer structures. For convenience of processing, the intake chamfer 3 and/or the exhaust chamfer 4 are preferably rounded rotary chamfers, i.e., the intake chamfer 3 and/or the exhaust chamfer 4 are chamfered structures machined after the rotary features remove cylinder head material.

The chamfer structure with different longitudinal section shapes can be obtained according to different rotary processing surfaces, for example, after the cylinder cover material is removed by adopting a conical rotary processing surface, the longitudinal section of the obtained chamfer structure is in a linear structure. Preferably, the longitudinal section of the inlet chamfer 3 and/or the longitudinal section of the outlet chamfer 4 is a straight line or a curved line.

It is further preferred that the longitudinal section of the inlet chamfer 3 and/or the longitudinal section of the outlet chamfer 4 is a curve that is convex in the direction of the cylinder interior, as shown in fig. 2, in which case the chamfer surface that is convex in the cylinder prevents the flow separation of the air flow as it passes through the chamfer, thus ensuring more air flow into the communication groove 9.

It should be noted that the center line of revolution of the inlet chamfer 3 and/or the exhaust chamfer 4 may be arranged in parallel with the inlet throat axis 11, or may be arranged obliquely with respect to the inlet throat axis 11.

Preferably, the revolution center line (intake chamfer revolution center line 12) of the intake chamfer 3 is obliquely arranged relative to the intake throat axis 11 and the lower end opening of the intake chamfer 3 is arranged towards the exhaust throat 2, so that a wider chamfer surface can be processed on the edge of the side, close to the exhaust throat 2, of the intake throat 1, and meanwhile, the transition between the chamfer surface on the side and the cylinder head bottom surface 17 and the wall surface of the intake throat 1 is smoother, so that the kinetic energy loss of airflow flowing through the intake chamfer 3 is reduced. Meanwhile, the center line of revolution of the exhaust chamfer 4 may also be arranged obliquely with respect to the axis of the exhaust throat 2 and the lower end opening of the exhaust chamfer 4 is arranged toward the intake throat 1.

The inclination angle of the rotation center line of the inlet chamfer 3 with respect to the inlet throat axis 11 and the inclination angle of the rotation center line of the exhaust chamfer 4 with respect to the exhaust throat axis may be designed to be equal or different. Preferably, the inclination angle θ of the intake chamfer gyration center line 12 with respect to the intake throat axis 11 is greater than 0 ° and equal to or less than 30 °, and specifically, the inclination angle θ may be 30 °, or 20 °, or 10 °, or 5 °. The angle of inclination of the center of gyration of the exhaust chamfer 4 with respect to the axis of the exhaust throat 2 is greater than 0 ° and equal to or less than 30 °, and specifically may be 30 ° or 20 ° or 10 ° or 5 °, similar to the angle of inclination of the center of gyration of the intake chamfer 12.

It should be noted that the cylinder head provided by the present invention may be suitable for a two-valve engine or a multi-valve engine, that is, the number of the intake throats 1 may be one or two or three or more, and the number of the exhaust throats 2 may also be one or two or more, which is not described herein again.

In a preferred embodiment scheme, the cylinder cover comprises a first air inlet throat 19 and a second air inlet throat 20, the distance between the first air inlet throat 19 and the cylinder cover air inlet 18 is smaller than the distance between the second air inlet throat 20 and the cylinder cover air inlet 18, a first air inlet valve seat ring 13 is arranged in the first air inlet throat 19, a second air inlet valve seat ring 14 is arranged in the second air inlet throat 20, and the height H1 of the first air inlet valve seat ring 13 from the bottom surface 17 of the cylinder cover is larger than the height H2 of the second air inlet valve seat ring 14 from the bottom surface 17 of the cylinder cover. The first inlet throat 19 is connected to the first inlet channel 19, and the second inlet throat 20 is connected to the second inlet channel 16, as shown in fig. 4.

An air inlet valve seat ring 10 is installed in the air inlet throat 1 and used for being matched with an air inlet valve to be opened and closed so as to realize the on-off control of air inlet, the air inlet throat 1 is connected with an air inlet channel and used for guiding air inlet flow, the cylinder cover air inlet 18 is an air inlet of the air inlet channel, a connecting line of the center of the first air inlet throat 19 and the center of the second air inlet throat 20 forms a certain angle with the central line of a crankshaft of the engine, the distance between one air inlet throat and the cylinder cover air inlet 18 is inevitably larger than the distance between the other air inlet throat and the cylinder cover air inlet 18, and the distance L4 between the second air inlet throat 20 and the cylinder cover air inlet 18 in the scheme is larger than the distance L3 between the first air inlet throat 19 and the cylinder cover air inlet 18, as shown in figure 5. The height H1 of the first intake valve seat ring 13, which is closer to the cylinder cover inlet 18, from the bottom surface 17 of the cylinder cover is designed to be higher than the height H2 of the second intake valve seat ring 14 from the bottom surface 17 of the cylinder cover, and the function of the scheme is to improve the flow capacity of the air passage to the maximum extent on the premise of ensuring the air passage tumble ratio. The principle is that the first inlet duct 15 to which the first inlet throat 19 is connected can be designed to be shorter and thicker due to the different distances of the two inlet valve races to the cylinder head inlet 18, so that there is no space to modify the shape of the air duct to make it more advantageous to generate tumble flow. Therefore, the height H1 of the first intake valve seat ring 13 from the bottom surface 17 of the cylinder cover is increased, so that the flow guiding length of the guiding wall below the first intake valve seat ring 13 is further prolonged in the opening process of the valve, and tumble flow is more favorably generated. Meanwhile, the air flow is guided by the guide wall, so that the movement towards the target direction (towards the exhaust throat 2) is facilitated, and the air flow interference in the direction of the central connecting line of the two intake valves can be reduced.

Preferably, the height difference between the first intake valve seat ring 13 and the second intake valve seat ring 14 is greater than 0 and less than or equal to 0-0.2 times of the intake valve diameter.

It should be noted that, for a cylinder head having two or three or more intake throats 1, the number of intake ports is two or three or more, and the respective intake ports may be arranged separately from each other, or upstream portions (i.e., a section near the head intake port 18) of the respective intake ports may be communicated with each other to form an integrated intake section.

It should be noted that, when the number of the intake throats 1 in the present invention is two or three or more, the intake chamfers 3 of the bottom holes of each intake throat 1 may all adopt the same structure or arrangement, or adopt different structures or arrangements, for example, for a cylinder head structure having two intake throats 1, the two intake throats 1 are designed to be asymmetric structures, the intake chamfers 3 of the bottom holes of one intake throat 1 may be designed to be circular revolving chamfers with linear longitudinal sections, and the intake chamfers 3 of the bottom holes of the other intake throat 1 may be designed to be curved.

It should be noted that the intake port of the intake passage (i.e. the head intake port 18) is generally disposed at a side surface of the cylinder head, and of course, the cylinder head provided by the present invention may also have the head intake port 18 disposed at a top surface or a bottom surface of the cylinder head, so as to facilitate installation and arrangement of engines of different models.

The invention also provides a gas engine comprising the cylinder cover. The derivation process of the beneficial effects generated by the gas engine is substantially similar to the derivation process of the beneficial effects brought by the cylinder cover, and therefore, the description is omitted.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.