CN212106036U

CN212106036U - Combustion chamber structure of two-stroke engine

Info

Publication number: CN212106036U
Application number: CN202020089218.XU
Authority: CN
Inventors: 苏杭; 马瑞博; 李双清; 柳茂斌; 李连豹
Original assignee: Zhejiang Geely Holding Group Co Ltd; Ningbo Geely Royal Engine Components Co Ltd
Current assignee: Zhejiang Geely Holding Group Co Ltd; Ningbo Geely Royal Engine Components Co Ltd
Priority date: 2020-01-15
Filing date: 2020-01-15
Publication date: 2020-12-08
Anticipated expiration: 2030-01-15

Abstract

The utility model discloses a two-stroke engine's combustion chamber structure, two-stroke engine includes cylinder cap and piston, the cylinder cap is located the piston top, the cylinder cap below with form the combustion chamber between the piston top, the combustion chamber structure including set up in the cylinder cap bottom adopts the first crowded gas face of whole face rotary machining formation and set up in the cooperation of piston head first crowded gas face just adopts the second crowded gas face of rotary machining formation. The utility model discloses a set up in the first crowded gas face that adopts whole face rotation machining to form bottom the cylinder cap and set up in the first crowded gas face of piston head cooperation and adopt the second crowded gas face that rotation machining formed, both mutually support crowded gas, play good water conservancy diversion effect to the air current, the air current motion of high tumble flow has been obtained, make when the burning is finished, waste gas and the gas mixture distribution obvious region that does not burn, the fresh air overflow volume reduces, the burning oil consumption is more abundant, thereby improve combustion efficiency, reduce and discharge.

Description

Combustion chamber structure of two-stroke engine

Technical Field

The utility model relates to the technical field of automobiles, especially, relate to a two-stroke engine's combustion chamber structure.

Background

At present, the extended range electric vehicle is widely used, and when the vehicle-mounted rechargeable energy storage system cannot meet the requirement of the endurance mileage, the vehicle-mounted auxiliary power supply device provides electric energy for the power system so as to prolong the endurance mileage. The extended range electric motor car of using on the existing market adopts two-stroke engine more, compare four-stroke engine can effectively solve bulky, problem with high costs, nevertheless simultaneously, traditional two-stroke engine's combustion chamber structure is mostly for setting up the pit face at the piston top surface for simple and constitute the combustion chamber structure with cylinder cap lower terminal surface, this kind of design is because the combustion chamber structure, factors such as size and piston top position all have great influence to gas motion and oil-gas mixture in the cylinder, thereby make the scavenging process uncontrollable, fresh air overflow volume is high, the burning is insufficient, lead to the combustion efficiency can't further improve, the oil consumption is high and the emission is poor.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a can improve combustion efficiency's two-stroke engine's combustion chamber structure.

The utility model provides a two-stroke engine's combustion chamber structure, two-stroke engine includes cylinder cap and piston, the cylinder cap is located the piston top, the cylinder cap below with form the combustion chamber between the piston top, the combustion chamber structure including set up in the cylinder cap bottom adopts the first crowded gas face of whole face rotary machining formation and set up in the cooperation of piston head first crowded gas face just adopts the second crowded gas face of rotary machining formation.

Further, the vertex angle of the first air-squeezing surface is the same as that of the second air-squeezing surface, and the vertex angle is 120-160 degrees.

Further, the cylinder cap includes protruding face, protruding face is located cylinder cap upper portion, the piston include with protruding face corresponds the pit face that sets up, protruding face with pit face forms the cavity body, the cavity body is located the combustion chamber.

Furthermore, an inner concave surface is arranged between the convex surface and the first air squeezing surface, the pit surface comprises a first pit surface and a second pit surface, the first pit surface is adjacent to the second pit surface, the first pit surface is a cylindrical surface, and the first pit surface is opposite to the inner concave surface.

Furthermore, the radius of the inner concave surface is 10-30 mm, the radius of the first concave surface is 70-90 mm, and the ratio of the height of the second concave surface to the height of the piston head is 0.5-0.85.

Further, the two-stroke engine still includes the (air) intake valve, the cylinder cap still including being located cylinder cap upper portion is used for the installation the intake duct of (air) intake valve, the direction is arranged to the intake duct with pit face opposite direction.

Furthermore, the middle part of the cylinder cover is provided with a wedge-shaped part, and the convex surface is positioned on the narrow side of the wedge-shaped part.

Further, the two-stroke engine also comprises an oil injector and a spark plug, wherein the oil injector and the spark plug are arranged in the middle of the wedge-shaped part, and the oil injector is mounted on the convex surface.

Further, the two-stroke engine further comprises an intake valve and an intake valve seat ring, the intake valve is positioned on the upper portion of the cylinder cover, the included angle between the convex surface and the intake valve seat ring is 125-155 degrees, and the included angle between the convex surface and the intake valve seat ring is smaller than the vertex angle of the first air squeezing surface.

Further, the two-stroke engine also comprises a cylinder body, wherein the cylinder body comprises a cylinder wall and an exhaust passage, and the exhaust passage is positioned at the lower part of the cylinder wall.

The utility model provides a two-stroke engine's combustion chamber structure is through setting up in the first crowded gas face that adopts whole face rotation machining to form bottom the cylinder cap and set up in the first crowded gas face of piston head cooperation and adopt the second crowded gas face that rotation machining formed, both mutually support and crowd gas, play good water conservancy diversion effect to the air current, the air current motion of high tumble has been obtained, make when the burning finishes, waste gas and the gas mixture that does not burn distribute obvious region, fresh air overflow volume reduces, the burning is more abundant, thereby improve combustion efficiency, reduce and discharge. The vertex angle of the first air squeezing surface is the same as that of the second air squeezing surface and ranges from 120 degrees to 160 degrees, so that sufficient air squeezing area is ensured, and full matching between the first air squeezing surface and the second air squeezing surface is facilitated. Simultaneously through first pit face relative with interior concave surface, the radius of first pit face and interior concave surface radius mutually support promptly, the gas mixture of being convenient for lets first crowded gas face and the crowded gas face of second cooperate better in combustion process to obtain better air current motion.

Drawings

Fig. 1 is a front combination schematic diagram of a two-stroke engine according to an embodiment of the present invention.

Fig. 2 is a schematic cross-sectional view of a cylinder head in the two-stroke engine shown in fig. 1.

Fig. 3 is a schematic cross-sectional view of a piston in the two-stroke engine of fig. 1.

Fig. 4 is a schematic layout of the two-stroke engine of fig. 1.

Fig. 5 is a schematic view of the arrangement of pistons in the two-stroke engine shown in fig. 1.

Detailed Description

The following detailed description of the embodiments of the present invention is provided with reference to the accompanying drawings and examples. The following examples are intended to illustrate the invention, but are not intended to limit the scope of the invention.

As shown in fig. 1 to 5, in the present embodiment, a combustion chamber structure of a two-stroke engine is provided, the two-stroke engine including a cylinder head 2, a piston 4, an intake valve 1, a cylinder block, an injector 10, and a spark plug 11. The cylinder head 2 is located above the piston 4. A combustion chamber 16 is formed between the underside of the cylinder head 2 and the upper side of the piston 4. The combustion chamber structure includes a first squish face and a second squish face 12. The first squish face includes a first portion 6 and a second portion 9. The first air squeezing surface is arranged at the bottom of the cylinder cover 2, and the second air squeezing surface 12 is arranged at the head of the piston 4.

As shown in fig. 1, 2 and 4, the cylinder head 2 includes a convex surface 15, and a wedge portion 8 is provided in the middle of the top. In this embodiment, the wedge portion 8 is the wedge face, and the wedge face heat radiating area is little, and the heat loss is little, and the gas mixture can form good high tumble flow air current in the compression stroke, has improved mixing quality. The raised surface 15 is located on the narrower side (left side in the figure) of the wedge 8 and serves to concentrate the airflow. An inner concave surface (not marked) is arranged between the convex surface 15 and the first air squeezing surface, and the radius R of the inner concave surface₁10-30 mm. And an air inlet channel for installing the air inlet valve 1 is arranged on the outer side of the other side of the wedge-shaped part 8. In this embodiment, the intake passage includes the first intake passage 5 and the second intake passage 7, and a sufficient amount of intake air is ensured.

As shown in fig. 2 and 4, the spark plug 11 and the injector 10 are disposed in the middle of the wedge portion 8 in the middle of the cylinder head 2, and the injector 10 is mounted on the convex surface 15. In the embodiment, the fuel injector 10 is directly arranged on the cylinder cover 2, so that the two-stroke engine adopts a mode of direct injection in the cylinder, fuel can be directly injected into the cylinder and is fully mixed with fresh air, and the fuel efficiency is greatly improved.

As shown in fig. 1, 2 and 4, the intake valve 1 includes an intake valve seat (not labeled), the intake valves 1 are respectively and correspondingly installed in the first intake passage 5 and the second intake passage 7, and the opening and closing of the intake ports of the first intake passage 5 and the second intake passage 7 are respectively controlled by the intake valve 1.

The top of the head of the piston 4 includes a concave surface arranged corresponding to the convex surface 15. The convex surface 15 and the concave surface form a cavity body which is positioned in the combustion chamber 16 and is convenient to distributeThe mixture of the combustion. In the present embodiment, the pit surface includes a first pit surface 13 and a second pit surface 14, and the first pit surface 13 adjoins the second pit surface 14. In this embodiment, the first pit surface 13 has a cylindrical shape and the second pit surface 14 has a planar shape, and is easily fitted to the combustion chamber 16 to satisfy the compression ratio required for the two-stroke engine. In other embodiments, the first pit surface 13 and the second pit surface 14 may have other shapes, and may be used as the first pit surface 13 and the second pit surface 14 in the present embodiment as long as they can correspond to the convex surface 15. Radius R of the first pit surface 13₂70-90 mm, height h of the second pit surface 14₂Height h of the head of the piston 4₁The ratio is 0.5-0.85, and the radius and the height in the range enable fresh air and fuel oil to be fully mixed, so that combustion is more sufficient.

As shown in fig. 2 and 3, the direction of the air intake passage is opposite to the direction of the pit surface, in order to form a suitable combustion space.

As shown in fig. 1, in the present embodiment, the cylinder block includes a cylinder wall 3 and an exhaust passage (not shown) located at a lower portion of the cylinder wall 3. Because the present embodiment adopts the scheme of air intake of the cylinder head 2 and air exhaust of the cylinder wall 3, the scavenging mode is the reverse direct current mode. The arrangement scheme cancels the exhaust valve and the valve actuating mechanism thereof, has small volume, less parts, light weight and low cost, and improves NVH (noise, vibration and harshness).

As shown in fig. 2 and 3, the first air squeezing surface is formed by full-surface rotary processing, the second air squeezing surface 12 is formed by rotary processing in cooperation with the first air squeezing surface, and air squeezing can be better performed by arranging the first air squeezing surface and the second air squeezing surface 12 which are mutually matched, so that a good flow guiding effect is achieved on air flow, and high-tumble air flow motion is obtained. Vertex angle theta of first inflatable surface₁Angle of vertex theta with the second inflatable surface₁Similarly, when the first and second pumping surfaces 12 are engaged with each other, the tumble ratio, the flow coefficient, and the distribution of the mixture can be formed to meet the needs of the user, and the combustion efficiency can be improved finally. Vertex angle theta₁All are 120 degrees to 160 degrees, and the apex angle theta₁In this range it is advantageous to ensure a sufficient fit between the two and to ensure a sufficient squeezingArea of gas.

As shown in fig. 1, 2 and 3, the first squish face is arranged at the bottom of the cylinder cover 2 and is processed by rotating the whole face, and the second squish face 12 is arranged at the head of the piston 4 and is matched with the first squish face and is formed by rotating the second squish face 12, so that fresh air and fuel oil can be fully mixed, when the mixed gas is compressed and combusted, the piston 4 makes reciprocating linear motion in the cylinder body and is matched with the cylinder cover 2 to squib gas, the surface of the mixed gas contacted with the cylinder cover 2 is the first squish face, and the surface of the mixed gas contacted with the piston 4 is the second squish face 12. Cylinder cap 2 and piston 4 first crowded face and the crowded face 12 of second that mutually supports the production, good water conservancy diversion effect has been formed to the air current through crowded gas, obtain the air current motion of high tumble, make when the burning is ended, waste gas and the obvious region of unburnt gas mixture distribution, waste gas distributes in cylinder wall 3 below promptly, the gas mixture of unburnt distributes in cavity body department, thereby when exhaust gas, guide exhaust gas that can be better discharges, reduce the fresh air outflow, the burning is more abundant, thereby improve combustion efficiency, reduce oil consumption and emission.

In the present embodiment, the angle θ between the convex surface 15 and the intake valve seat ring is shown in FIG. 2₂125-155 degrees, and the included angle theta is formed because the oil injector 10 is arranged on the convex surface 15₂The range of (1) is set to ensure that the oil mist sprayed from the injector 10 is uniformly distributed in the combustion chamber, thereby improving the combustion efficiency. The included angle theta between the convex surface 15 and the inlet valve seat ring₂Smaller than the vertex angle theta of the first inflatable surface₁In order to be able to better organize the air flow movement, the combustion efficiency is increased.

In the present embodiment, as shown in fig. 2 and 3, the first pit surface 13 is opposed to the concave surface between the convex surface 15 and the first squish surface, that is, the concave surface radius R₁Radius R of the first pit surface₂The mutual cooperation is convenient for the mixture to let the first squish face better cooperate with the second squish face 12 in the combustion process, thereby obtaining better air current motion.

In this embodiment, the first pit surface 13 is further matched with a transition fillet (not labeled) at the head of the piston 4 to form a combustion space, so that the combustion area of the mixed gas is increased, and the mixed gas is combusted more sufficiently.

In this document, the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", "vertical", "horizontal", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for the sake of clarity and convenience of description of the technical solutions, and thus, should not be construed as limiting the present invention.

As used herein, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, including not only those elements listed, but also other elements not expressly listed.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The utility model provides a two-stroke engine's combustion chamber structure, its characterized in that, two-stroke engine includes cylinder cap (2) and piston (4), cylinder cap (2) are located piston (4) top, cylinder cap (2) below with form combustion chamber (16) between piston (4) top, the combustion chamber structure including set up in cylinder cap (2) bottom adopts the first crowded gas face of whole face gyration processing formation and set up in piston (4) head cooperation first crowded gas face just adopts second crowded gas face (12) that gyration processing formed.

2. The combustion chamber structure of a two-stroke engine as claimed in claim 1, characterized in that the apex angle of the first squish surface is the same as the apex angle of the second squish surface (12), said apex angle (θ)₁) Is 120-160 degrees.

3. The combustion chamber structure of a two-stroke engine as claimed in claim 1, characterized in that said cylinder head (2) comprises a convex surface (15), said convex surface (15) being located at the upper part of said cylinder head (2), said piston (4) comprising a concave surface arranged in correspondence with said convex surface (15), said convex surface (15) and said concave surface forming a cavity body, said cavity body being located in said combustion chamber (16).

4. A combustion chamber structure of a two-stroke engine according to claim 3, wherein an inner concave surface is provided between the convex surface (15) and the first squish surface, the pit surface includes a first pit surface (13) and a second pit surface (14), the first pit surface (13) is adjacent to the second pit surface (14), the first pit surface (13) is a cylindrical surface, and the first pit surface (13) is opposite to the inner concave surface.

5. The combustion chamber structure of a two-stroke engine as set forth in claim 4, wherein the concave inner surface radius (R) is₁) 10-30 mm, the radius (R) of the first pit surface (13)₂) 70-90 mm, the height (h) of the second pit surface (14)₂) Height (h) of the head of the piston (4)₁) The ratio is 0.5 to 0.85.

6. The combustion chamber structure of a two-stroke engine as claimed in claim 3, characterized in that the two-stroke engine further comprises an intake valve (1), the cylinder head (2) further comprises an intake passage located at the upper part of the cylinder head (2) for mounting the intake valve (1), and the direction of the intake passage is opposite to the direction of the pit surface.

7. A combustion chamber structure of a two-stroke engine according to claim 3, characterized in that the cylinder head (2) is provided with a wedge (8) in the middle, and the raised surface (15) is located on the narrower side of the wedge (8).

8. A combustion chamber structure of a two-stroke engine according to claim 7, characterized in that the two-stroke engine further comprises an injector (10) and a spark plug (11), the injector (10) and the spark plug (11) being arranged in the middle of the wedge portion (8), the injector (10) being mounted on the raised surface (15).

9. A combustion chamber arrangement for a two-stroke engine according to claim 3, characterized in that the two-stroke engine further comprises an inlet valve (1), the inlet valve (1) further comprises an inlet valve seat insert, the inlet valve (1) is located in the upper part of the cylinder head (2), and the angle (θ) between the convex surface (15) and the inlet valve seat insert is₂) Is 125-155 degrees, and the included angle (theta) between the convex surface (15) and the inlet valve seat ring₂) Less than the apex angle (theta) of the first squish face₁)。

10. The combustion chamber structure of a two-stroke engine, as recited in claim 9, characterized in that said two-stroke engine further comprises a cylinder block including cylinder walls (3) and an exhaust passage located below said cylinder walls (3).