High-power-density two-stroke compression ignition engine structure

Abstract

The invention discloses a high-power-density two-stroke compression-ignition engine structure which comprises an air cylinder body, a piston rod and a piston rod. The cylinder cover is integrally arranged at the top of the cylinder body and comprises two inclined plane structures which are symmetrically distributed; the exhaust system comprises two valve passages arranged on the same side of the cylinder cover, the peripheral sides of the valve passages are communicated with exhaust passages, and the inner ends of the valve passages are communicated with the combustion chamber; and the air inlet system comprises two scavenging groups, and each scavenging group comprises a plurality of scavenging ports communicated with the combustion chamber. By arranging the valve type exhaust port, a single-side air port-air port type air exchange mode is improved into an up-down air port-valve type air exchange mode, the layout of air ports and air valves is optimized, the air inlet and exhaust process is smoother, the air exchange efficiency of the engine is improved, the air flow direction in the air exchange process is smooth, and the air exchange efficiency of the engine is improved. The relative phase between intake and exhaust is easy to change; ventilation quality can be effectively improved, and heat efficiency is improved.

Description

Technical Field

[0001] The present invention belongs to the field of engines, and particularly relates to a high power density two-stroke compression ignition engine structure. Background Art

[0002] In military vehicles, the engine ensures battlefield mobility with its high power and reliability, and can be regarded as the "heart" of armored vehicles. In the field of civilian vehicles, high-performance engines also lead the green development and meet the needs of high-speed and heavy-load. With the process of military modernization, the performance requirements for the power system of armored vehicles are increasing day by day. In order to achieve higher mobility, the engine design is gradually tending towards miniaturization and lightweight, which also promotes high power density to become an important goal for the development of military and civilian vehicle engines. Compared with spark-ignition engines, compression-ignition engines are not limited by detonation, have a very high compression ratio, and have better thermal efficiency and economy than spark-ignition engines. Compared with four-stroke engines, the two-stroke engine doubles the working frequency at the same rotational speed and has great potential to significantly improve the power density. However, in traditional two-stroke compression ignition engines, the intake and exhaust ports are on the same side, and the gas needs to flow upward and then downward to complete scavenging. A considerable part of the fuel-air mixture is discharged without burning or incomplete combustion, resulting in low scavenging quality, problems of incomplete scavenging and short circuit, so the thermal efficiency is low, the emissions are high, and pollution is caused. Summary of the Invention

[0003] The purpose of the present invention is to overcome the above problems existing in the prior art, and provide a high power density two-stroke compression ignition engine structure, which uses an air-port-valve structure arranged up and down to solve the problems of low scavenging efficiency, incomplete scavenging and short circuit of traditional two-stroke compression ignition engines.

[0004] To achieve the above technical purpose and reach the above technical effect, the present invention is realized through the following technical solutions:

[0005] A high power density two-stroke compression ignition engine structure, comprising:

[0006] A cylinder block, containing a combustion chamber;

[0007] A cylinder head, integrally arranged on the top of the cylinder block, including two symmetrically distributed inclined plane structures;

[0008] An exhaust system, including two valve passages arranged on the same side of the cylinder head, an exhaust passage is communicated with the periphery of the valve passage, and the inner end of the valve passage is communicated with the combustion chamber;

[0009] An intake system, including two groups of scavenging groups, and each scavenging group includes a plurality of scavenging ports communicated with the combustion chamber.

[0010] Further, it also includes:

[0011] The valve guide is arranged in the valve passage;

[0012] The valve is installed in cooperation with the valve guide;

[0013] The valve seat is installed in cooperation with the inner end of the valve passage.

[0014] Furthermore, the valve is a flat-bottom valve, the back of its head adopts a conical structure, and is connected to the rod part through a transition radius.

[0015] Furthermore, each scavenging group includes four scavenging ports.

[0016] Furthermore, the width of a single scavenging port corresponds to a central angle of 23° along the circumferential side of the cylinder block.

[0017] Furthermore, the interval angle between two scavenging groups is 58°, and the interval angle between two adjacent scavenging ports in each scavenging group is 10°.

[0018] Furthermore, the length of the scavenging port is 18 mm, the width is 16.66 mm, the height from the upper end of the scavenging port to the top dead center of the cylinder block is 64 mm, the shaft inclination angle is 90°, and the swirl direction angle is 20°.

[0019] Furthermore, the combustion chamber is a re-entrant ω-shaped combustion chamber.

[0020] Furthermore, it also includes a protective structure installed in cooperation, and this protective structure includes:

[0021] Two upper clamping seats are symmetrically installed to form a limit on the circumferential side of the cylinder block and are fitted and installed with the top of the scavenging port;

[0022] The lower clamping seat is fitted and installed with the bottom of the scavenging port;

[0023] The spacer sleeve is installed between the upper clamping seat and the lower clamping seat and has the same height as the scavenging port;

[0024] The fastener is used to fixedly connect the upper clamping seat, the spacer sleeve, and the lower clamping seat in sequence;

[0025] The support base is installed below the cylinder block to form an elastic support;

[0026] The anti-rotation limiting part is fixedly installed on the upper clamping seat, and the top is used to limit between the exhaust passages;

[0027] The connecting top seat is fixedly installed at the bottom of the lower clamping seat and is slidably connected to the support base;

[0028] The elastic part is installed outside the connecting top seat, and the bottom end is connected to the support base.

[0029] Further, the upper clamping seat includes an arc-shaped clamping block and positioning connection blocks symmetrically arranged at both ends of the arc-shaped clamping block. A positioning through-hole is provided through the middle of the positioning connection block, and a first positioning screw hole is provided in the middle of the arc-shaped clamping block;

[0030] The lower clamping seat is of an annular plate structure, with a number of second positioning screw holes evenly distributed on its surface along the circumferential direction, and third positioning screw holes corresponding to the positioning through-holes; a number of guiding and limiting holes are also provided;

[0031] The fastener passes through the positioning through-hole, spacer sleeve and is fixedly connected to the third positioning screw hole;

[0032] The support base includes an annular support bottom plate. The surface of the annular support bottom plate is provided with sliding connection columns corresponding to the second positioning screw holes, and guiding connection columns cooperating with the guiding and limiting holes. Elastic connection pieces are symmetrically provided at the top of the guiding connection columns, and limiting protrusions are provided on the outer sides of the elastic connection pieces;

[0033] The connecting top seat includes a positioning top column cooperating with the second positioning screw hole. A rotation limiting block and an installation connection column are successively provided at the bottom of the positioning top column. A sliding connection hole cooperating with the sliding connection column is provided through the middle of the connecting top seat; an elastic member is installed on the outer side of the installation connection column;

[0034] The anti-rotation limiting member includes a central limiting rod. An anti-rotation connection column cooperating with the first positioning screw hole is provided at the bottom end of the central limiting rod. The peripheral side of the top end of the central limiting rod is in close contact with the surface of the exhaust passage, and a rotation positioning block is provided on the top end surface of the central limiting rod.

[0035] The beneficial effects of the present invention are:

[0036] By providing a valve-type exhaust port, the present invention improves the single-sided port-port type ventilation mode into an up-and-down arranged port-valve type ventilation mode, optimizes the layout of the ports and valves, makes the intake and exhaust processes smoother, improves the ventilation efficiency of the engine, makes the gas flow smooth during the ventilation process, and is easy to change the relative phase between intake and exhaust. It can effectively improve the ventilation quality and thermal efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The drawings described herein are used to provide a further understanding of the present invention, form a part of this application, and the illustrative embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0038] Figure 1 is a schematic diagram of the port-valve structure of the present invention;

[0039] Figure 2 is a schematic diagram of the port-valve structure of the present invention;

[0040] Figure 3It is a cross-sectional view of the air port valve structure of the present invention;

[0041] Figure 4 It is a top view of the air port valve structure of the present invention;

[0042] Figure 5 It is a bottom view of the air port valve structure of the present invention;

[0043] Figure 6 It is a schematic diagram of the installation of the protection structure of the present invention;

[0044] Figure 7 It is a partial schematic diagram of the protection structure of the present invention;

[0045] Figure 8 It is a partial schematic diagram of the protection structure of the present invention;

[0046] Figure 9 It is a partial schematic diagram of the protection structure of the present invention;

[0047] Figure 10 It is a schematic diagram of the full load characteristic power - speed of the present invention with the air port length of 10mm and the air port width corresponding to the central angles of 8°, 11°, 14°, 17°, 20°, 23° along the circumferential side of the cylinder block;

[0048] Figure 11 It is a schematic diagram of the full load characteristic power - speed of the present invention with the air port length of 12mm and the air port width corresponding to the central angles of 8°, 11°, 14°, 17°, 20°, 23° along the circumferential side of the cylinder block;

[0049] Figure 12 It is a schematic diagram of the full load characteristic power - speed of the present invention with the air port length of 14mm and the air port width corresponding to the central angles of 8°, 11°, 14°, 17°, 20°, 23° along the circumferential side of the cylinder block;

[0050] Figure 13 It is a schematic diagram of the full load characteristic power - speed of the present invention with the air port length of 16mm and the air port width corresponding to the central angles of 8°, 11°, 14°, 17°, 20°, 23° along the circumferential side of the cylinder block;

[0051] Figure 14 It is a schematic diagram of the full load characteristic power - speed of the present invention with the air port length of 18mm and the air port width corresponding to the central angles of 8°, 11°, 14°, 17°, 20°, 23° along the circumferential side of the cylinder block;

[0052] Figure 15 It is a schematic diagram of the full load characteristic power - speed of the present invention with the air port width corresponding to the central angle of 23° along the circumferential side of the cylinder block and the air port lengths of 10mm, 12mm, 14mm, 16mm, 18mm;

[0053] Figure 16 When the air inlet length of the present invention is 18 mm and the air inlet width corresponds to a central angle of 23° along the circumferential side of the cylinder block, the schematic diagram of the full-load characteristic power-rotation speed at the heights of 60 mm, 64 mm, 68 mm, 72 mm, and 76 mm from the upper end of the air inlet to the top dead center of the cylinder block 4. Specific embodiments

[0054] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0055] In the description of the present invention, it should be understood that the terms "opening", "upper", "lower", "thickness", "top", "middle", "length", "inner", "periphery", etc. indicating the orientation or position relationship are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present invention.

[0056] As Figure 1-5 shown, a high-power density two-stroke compression ignition engine structure includes:

[0057] A cylinder block 4 containing a combustion chamber 6;

[0058] A cylinder head 3 integrally provided at the top of the cylinder block 4, including two symmetrically distributed inclined plane structures;

[0059] An exhaust system, including two valve passages 2 provided on the same side of the cylinder head 3, an exhaust passage 1 communicating with the circumferential side of the valve passage 2, and the inner end of the valve passage 2 communicating with the combustion chamber 6;

[0060] An intake system, including two groups of scavenging groups, each scavenging group including a plurality of scavenging ports 5 communicating with the combustion chamber 6.

[0061] As a specific embodiment of the present invention, it further includes:

[0062] A valve guide provided in the valve passage 2;

[0063] A valve, cooperatively installed with the valve guide;

[0064] A valve seat, cooperatively installed with the inner end of the valve passage 2.

[0065] As a specific embodiment of the present invention, the valve is a flat-bottom valve, the back of its head adopts a conical structure, and is connected to the rod part through a transition radius. The overhead double-valve structure makes the combustion chamber 6 more compact, allows the use of a higher compression ratio, reduces the intake and exhaust resistance, and can effectively improve the performance of the engine.

[0066] As a specific embodiment of the present invention, in order to reasonably set the number of scavenging ports 5, each scavenging group includes four scavenging ports 5.

[0067] As a specific embodiment of the present invention, the width of a single scavenging port 5 corresponds to a central angle of 23° along the circumferential side of the cylinder block 4.

[0068] As a specific embodiment of the present invention, the interval angle between two scavenging groups is 58°, and the interval angle between two adjacent scavenging ports 5 within each scavenging group is 10°.

[0069] As a specific embodiment of the present invention, the length of the scavenging port 5 is 18 mm, the width is 16.66 mm, the height from the upper end of the scavenging port 5 to the top dead center of the cylinder block 4 is 64 mm, the shaft inclination angle is 90°, and the swirl direction angle is 20°. Compared with the traditional return and cross-flow scavenging methods, the direct-current scavenging method of the present invention has higher scavenging efficiency.

[0070] As a specific embodiment of the present invention, the combustion chamber 6 is a constricted ω-shaped combustion chamber, which helps to form a vortex to better organize the flow of the in-cylinder gas.

[0071] The present invention adopts an upper and lower arranged port-valve type gas exchange mode, making the intake and exhaust processes smoother, improving the gas exchange efficiency of the engine, making the gas flow direction smooth during the gas exchange process, effectively improving the gas exchange quality, increasing the thermal efficiency, and reducing emissions.

[0072] Specific operating principle: The piston moves from the bottom dead center to the top dead center within one stroke. When the piston moves below the scavenging port 5, fresh air enters the scavenging port 5 at this time, and the air enters the cylinder block 4 for direct current flow. When the piston moves to the scavenging port 5, the scavenging port 5 will be blocked by the piston to achieve the closing of the scavenging port 5, that is, no more air intake. After that, the piston continues to move upward to compress the air. When the piston moves to the top dead center, the high-pressure mixed oil and gas explodes and expands, pushing the piston downward and then causing the crank to do work and rotate. At the same time, a large amount of exhaust gas is generated, and the overhead valve opens to discharge the exhaust gas, and then it is closed by the cam mechanism. Then the piston moves to the low position below the scavenging port 5 to perform a reciprocating stroke.

[0073] As Figure 6 shown, it also includes a cooperating protective structure, and this protective structure includes:

[0074] Two upper clamping seats 20 are symmetrically installed to form a limit on the circumferential side of the cylinder block 4 and are fitted and installed with the top of the scavenging port 5;

[0075] A lower clamping seat 10 is fitted and installed with the bottom of the scavenging port 5;

[0076] A spacer sleeve 30 is installed between the upper clamping seat 20 and the lower clamping seat 10 and has the same height as the scavenging port 5;

[0077] A fastener 40 is used to fixedly connect the upper clamping seat 20, the spacer sleeve 30, and the lower clamping seat 10 in sequence;

[0078] A support base 60 is installed below the cylinder block 4 to form an elastic support;

[0079] An anti-rotation limiting member 50 is fixedly installed on the upper clamping seat 20, and the top is used to limit between the exhaust passages 1;

[0080] A connecting top seat 70 is fixedly installed at the bottom of the lower clamping seat 10 and is slidably connected to the support base 60;

[0081] An elastic member 80 is installed outside the connecting top seat 70, and the bottom end is connected to the support base 60.

[0082] As Figure 7-9 shown, as a specific embodiment of the present invention, the upper clamping seat 20 includes an arc-shaped clamping block 201 and positioning connection blocks 202 symmetrically arranged at both ends of the arc-shaped clamping block 201. A positioning through hole 203 runs through the middle of the positioning connection block 202, and a first positioning screw hole 204 is provided in the middle of the arc-shaped clamping block 201.

[0083] The lower clamping seat 10 is of an annular plate structure, and a plurality of second positioning screw holes 101 are evenly distributed on the surface along the circumferential direction, as well as third positioning screw holes 102 corresponding to the positioning through holes 203; a plurality of guiding and limiting holes 103 are also provided.

[0084] The fastener 40 passes through the positioning through hole 203, the spacer sleeve 30 and is fixedly connected to the third positioning screw hole 102;

[0085] The support base 60 includes an annular support bottom plate 601. The surface of the annular support bottom plate 601 is provided with sliding connection columns 602 corresponding to the second positioning screw holes 101, as well as guiding connection columns 603 cooperating with the guiding and limiting holes 103. Elastic connection pieces 604 are symmetrically arranged at the top ends of the guiding connection columns 603, and limiting protrusions 605 are arranged outside the elastic connection pieces 604.

[0086] The connecting top seat 70 includes a positioning top column 701 that cooperates with the second positioning screw hole 101. A rotation limiting block 702 and an installation connecting column 703 are successively provided at the bottom of the positioning top column 701. A sliding connection hole 704 that cooperates with the sliding connection column 602 is provided through the middle of the connecting top seat 70. An elastic member 80 is installed outside the installation connecting column 703, and the elastic member 80 is specifically a spring structure.

[0087] The anti-rotation limiting member 50 includes a central limiting rod 501. An anti-rotation connecting column 503 that cooperates with the first positioning screw hole 204 is provided at the bottom end of the central limiting rod 501. The peripheral side of the top end of the central limiting rod 501 is in close contact with the surface of the exhaust passage 1, and a rotation positioning block 502 is provided on the top end surface of the central limiting rod 501.

[0088] During specific use, axial limitation of the overall structure can be formed under the cooperation of the upper clamping seat 20 and the lower clamping seat 10, and the scavenging port 5 can be prevented from being overly pressed through the setting of the spacer sleeve 30; through the cooperation of the connecting top seat 70 and the elastic member 80, the elastic support of the overall structure can be fully ensured, and the central through-hole structure of the annular support bottom plate 601 reserves a certain buffer space for the bottom of the cylinder block 4; through the close contact between the peripheral side of the top end of the central limiting rod 501 and the surface of the exhaust passage 1, limitation in the horizontal direction can be achieved, rotation in the horizontal direction can be avoided, and thus effective protection of the overall structure can be realized.

[0089] In the description of this specification, the description with reference to terms such as "one embodiment", "example", "specific example", etc. means 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 invention. In this specification, the schematic representations 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.

[0090] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art of this industry should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed.

Claims

1. A high power density two-stroke compression ignition engine structure, characterized in that: include: A cylinder block (4) containing a combustion chamber (6); The cylinder cover (3) is integrally arranged on the top of the cylinder body (4), and comprises two symmetrically distributed inclined surface structures; An exhaust system comprises two valve channels (2) arranged on the same side of a cylinder head (3), the peripheral side of the valve channels (2) being connected to an exhaust channel (1), and the inner end of the valve channels (2) being connected to a combustion chamber (6); The air intake system comprises two scavenging groups, each of which comprises a plurality of scavenging ports (5) connected to a combustion chamber (6).

2. A high power density two-stroke compression ignition engine structure according to claim 1, characterized in that: Also includes: A valve guide, arranged in the valve channel (2); The valve is installed in conjunction with the valve guide; The valve seat is mounted in cooperation with the inner end of the valve channel (2).

3. A high power density two-stroke compression ignition engine structure according to claim 2, characterized in that: The valve is a flat-bottom valve with a conical structure on the back of the head, which is connected to the stem through a transition radius.

4. A high power density two-stroke compression ignition engine structure according to claim 1, characterized in that: Each scavenging group comprises four scavenging ports (5).

5. A high power density two-stroke compression ignition engine structure according to claim 4, characterized in that: The width of a single scavenging port (5) corresponds to a central angle of 23° along the circumference of the cylinder body (4).

6. A high power density two-stroke compression ignition engine structure according to claim 5, characterized in that: The interval angle between the two scavenging groups is 58°, and the interval angle between two adjacent scavenging ports (5) in each scavenging group is 10°.

7. A high power density two-stroke compression ignition engine structure according to claim 1, characterized in that: The scavenging port (5) has a length of 18 mm and a width of 16.66 mm. The height from the upper end of the scavenging port (5) to the top dead center of the cylinder body (4) is 64 mm. The shaft inclination angle is 90°, and the swirl direction angle is 20°.

8. A high power density two-stroke compression ignition engine structure according to claim 1, characterized in that: The combustion chamber (6) is a contracted ω-shaped combustion chamber.

9. A high power density two-stroke compression ignition engine structure according to any one of claims 1 to 8, characterized in that: Also included is a protective structure for cooperative installation, the protective structure comprising: Two upper clamping seats (20) are symmetrically installed to limit the peripheral side of the cylinder body (4) and are installed in close contact with the top of the scavenging port (5); The lower clamping seat (10) is installed in close contact with the bottom of the scavenging port (5); A spacer (30) is installed between the upper clamping seat (20) and the lower clamping seat (10) and has the same height as the scavenging port (5); A fastener (40) is used to sequentially fix and connect the upper clamping seat (20), the spacer (30), and the lower clamping seat (10); A support base (60) is installed below the cylinder body (4) to form an elastic support; An anti-rotation limiting member (50) is fixedly mounted on the upper clamping seat (20), and the top portion is used to limit the position between the exhaust ducts (1); A connecting top seat (70) is fixedly mounted on the bottom of the lower clamping seat (10) and is slidably connected to the supporting base (60); The elastic member (80) is installed on the outside of the connecting top seat (70), and the bottom end is connected to the supporting base (60).

10. A high power density two-stroke compression ignition engine structure according to claim 9, characterized in that: The upper clamping seat (20) comprises an arc-shaped clamping block (201) and positioning connection blocks (202) symmetrically arranged at both ends of the arc-shaped clamping block (201), a positioning through hole (203) is provided in the middle of the positioning connection block (202), and a first positioning screw hole (204) is provided in the middle of the arc-shaped clamping block (201); The lower clamping seat (10) is an annular plate structure, and has a plurality of second positioning screw holes (101) uniformly distributed on the surface along the circumferential direction, and a third positioning screw hole (102) corresponding to the positioning through hole (203); and a plurality of guide limit holes (103); The fastener (40) passes through the positioning through hole (203), the spacer (30) and is fixedly connected to the third positioning screw hole (102); The support base (60) comprises an annular support base plate (601), the surface of the annular support base plate (601) is provided with a sliding connection column (602) corresponding to the second positioning screw hole (101), and a guide connection column (603) matched with the guide limit hole (103), the top of the guide connection column (603) is symmetrically provided with an elastic connection sheet (604), and the outer side of the elastic connection sheet (604) is provided with a limit protrusion (605); The connecting top seat (70) comprises a positioning top column (701) matched with the second positioning screw hole (101), a rotation limit block (702) and an installation connecting column (703) are sequentially arranged at the bottom of the positioning top column (701), and a sliding connection hole (704) matched with the sliding connection column (602) is arranged through the middle of the connecting top seat (70); an elastic member (80) is installed on the outer side of the installation connecting column (703); The anti-rotation limiter (50) comprises a central limiter rod (501), the bottom end of which is provided with an anti-rotation connection column (503) which matches with the first positioning screw hole (204), the top peripheral side of the central limiter rod (501) is in close contact with the surface of the exhaust duct (1), and the top surface of the central limiter rod (501) is provided with a rotation positioning block (502).

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