Engine piston, engine and vehicle

Abstract

The utility model relates to an engine piston, an engine and a vehicle, the engine piston comprises a piston main body, the piston main body is provided with a pin hole penetrating through the side wall, and the engine piston is characterized in that the top of the piston main body is provided with a pit; the bottom face of the pit is arranged to be of a plane structure in the horizontal direction of the pin hole, the bottom face of the pit is arranged to be of a cambered surface structure in the radial direction of the pin hole, and the bottom face of the pit and the top face of the piston body are in transition through a smooth curved surface. The cambered surface structure in the bottom surface of the pit can improve the tumble ratio of gas and the flowing speed of mixed gas, and the plane structure can restrain generation of vortexes, so that sufficient combustion of gas in a combustion chamber can be guaranteed, the compression ratio of the piston is improved, and the volume of the pit at the top of the piston is reduced on the premise that the high compression ratio of a methanol engine is met. The compression height of the piston is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of engine component design, in particular to an engine piston, an engine and a vehicle. Background Technique

[0002] The piston of an automobile engine is one of the main components in the engine. The top of the engine piston and the cylinder head together form a combustion chamber, and different shapes of the combustion chamber affect the thermal efficiency of engine combustion.

[0003] For existing engine pistons, especially methanol engine pistons, the top of the piston adopts a bowl-shaped structure with a flat bottom surface. The bowl-shaped structure is not conducive to the flow of the mixed gas inside the combustion chamber, the gas flow rate is low, which affects the tumble ratio. Moreover, the compression ratio required by methanol engines is higher than that of gasoline engines. The existing combustion chamber structure is not conducive to the improvement of the compression ratio, and the space for improving the engine thermal efficiency is low. Content of the Utility Model

[0004] In order to solve the technical problem that the top structure of the above-mentioned engine piston is not conducive to the flow of the mixed gas and the improvement of the compression ratio, resulting in a low space for improving the engine thermal efficiency, the utility model provides an engine piston and an engine.

[0005] To achieve the above object, the utility model provides an engine piston, including a piston body. A pin hole penetrating the side wall is provided on the piston body. A concave pit is provided at the top of the piston body. The bottom surface of the concave pit is set as an arc surface structure in the radial direction of the pin hole, and the bottom surface of the concave pit is set as a plane structure in the horizontal direction of the pin hole.

[0006] Further, the depth of the lowest point of the arc surface structure inside the piston body is the same as the depth of the plane structure inside the piston body.

[0007] Further, the arc surface structure and the plane structure are transitioned by a smooth curved surface.

[0008] Further, the bottom surface of the concave pit and the upper top surface of the piston body are transitioned by a smooth curved surface.

[0009] Further, the smooth curved surface where the arc surface structure transitions with the upper top surface of the piston body is set as an arc surface.

[0010] Further, a transition surface is provided between the plane structure and the upper top surface of the piston body, and the transition surface is inclined with respect to the upper top surface of the piston body.

[0011] Furthermore, second arc surfaces are arranged on both sides of the transition surface. The second arc surfaces are connected to the planar structure and the upper top surface of the piston body, and smooth transitions are provided among the transition surface, the second arc surfaces, and the arc surface.

[0012] Furthermore, a piston ring is arranged at the top of the piston body. The piston ring is sleeved on the outer wall of the piston body. The ring land above the piston ring is the fire land. The distance between the outer circular surface of the fire land and the intersection between the arc surface structure and the upper top surface of the piston body is 10 mm - 15 mm.

[0013] Another object of this embodiment is to provide an engine, which is provided with the above-mentioned engine piston.

[0014] Another object of this embodiment is to provide a vehicle, which is provided with the above-mentioned engine piston.

[0015] The above technical solution of the present utility model has the following advantages compared with the prior art:

[0016] (1) The arc surface structure in the bottom surface of the recess can increase the gas tumble ratio and the flow velocity of the mixed gas. The planar structure can suppress the generation of eddy currents, thereby ensuring the full combustion of the gas in the combustion chamber, increasing the compression ratio of the piston, reducing the volume of the recess at the top of the piston on the premise of meeting the high compression ratio of the methanol engine, and further reducing the compression height of the piston.

[0017] (2) The recess is connected through a smooth curved surface. The bottom of the recess and the top of the piston are connected through a transition surface and an arc surface, which can ensure the smooth flow of the mixed gas, accelerate the combustion speed, and further improve the thermal efficiency of the engine. Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 is a schematic structural view of the engine piston of the present utility model;

[0020] Figure 2 is a sectional view of the engine piston of the present utility model along the extension direction of the air flow channel;

[0021] Figure 3 is a sectional view of the engine piston of the present utility model along the axial direction of the piston pin.

[0022] Explanation of the reference numerals in the drawings in the specification: piston body - 1; pit - 2; upper top surface of the piston body - 3; pin hole - 4; arc surface structure - 5; plane structure - 6; first arc surface - 7; outer cylindrical surface of the firing shore - 8; transition surface - 9; second arc surface - 10. DETAILED DESCRIPTION

[0023] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the utility model, but not all of them. Based on the embodiments of the utility model, all other embodiments obtained by ordinary persons in the field without creative work should fall within the scope of protection of the utility model.

[0024] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0025] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0026] The utility model is described in detail with reference to the schematic diagram. When describing the embodiments of the utility model, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general proportion, and the schematic diagrams are only examples, which should not limit the scope of protection of the utility model. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0027] At the same time, in the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper, lower, left, right, inside and outside" are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0028] Unless otherwise clearly specified and defined in the present utility model, the terms "installation, connection, and coupling" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may also be a mechanical connection, an electrical connection, or a direct connection, and may also be indirectly connected through an intermediate medium, or may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0029] Engines include various types such as gasoline engines, methanol engines, and fuel engines. Among them, methanol engines have more advantages in terms of economy and environmental protection. However, in the actual application process, in order to make the methanol engine have the same performance as the traditional gasoline engine, the methanol engine requires a higher compression ratio than the traditional gasoline engine. The compression ratio refers to the degree to which the engine's mixture gas is compressed. The size of the compression ratio is related to the air flow at the inlet and outlet. The level of the compression ratio directly affects the thermal efficiency of the engine. The existing combustion chamber structure of methanol engines is not conducive to the improvement of the compression ratio. In order to increase the compression ratio of the existing methanol engine combustion chamber, the piston center of gravity is too high, so that the swing amount of the piston head during the piston operation is relatively large, which is likely to cause unstable piston movement. Moreover, the existing combustion chamber structure of methanol engines is not conducive to the flow of the mixture gas, further affecting the thermal efficiency of the engine.

[0030] Embodiment 1

[0031] To solve the above-mentioned problems, the following refers to Figures 1 to 3 Describe an engine piston provided according to this embodiment, including a piston body 1. A pin hole 4 penetrating the side wall is provided on the piston body 1. A piston pin is inserted into the piston body 1 from the pin hole 4 to transmit the gas force borne by the piston body 1. A concave pit 2 is provided at the top of the piston body 1. The bottom surface of the concave pit 2 is set as a planar structure 6 in the horizontal direction of the pin hole 4. The planar structure 6 can suppress the generation of gas vortices in the combustion chamber, reduce the turbulence intensity, can reduce heat loss, and improve the combustion efficiency; the bottom surface of the concave pit 2 is set as a curved surface structure 5 in the radial direction of the pin hole 4. The upper part of the curved surface structure 5 corresponds to the intake port and the exhaust port of the engine. The extending direction of the curved surface structure 5 is consistent with the air flow direction of the engine. When the gas enters the concave pit 2, it flows along the curved surface structure 5, which can increase the gas tumble ratio, improve the flow velocity of the mixture gas, thereby accelerating the combustion speed, and further improving the thermal efficiency of the engine. The concave pit structure in this embodiment makes the mixture gas flow smoothly and accelerates the combustion speed. Therefore, under the requirement of meeting the high compression ratio of the methanol engine, compared with the existing combustion chamber design, it has a smaller piston compression height, so that the piston center of gravity moves downward, and further can reduce the swing amplitude during the piston operation, ensuring the stability of the operation.

[0032] In one embodiment, the depth of the lowest point of the arc surface structure 5 inside the piston body 1 is the same as the depth of the plane structure 6 inside the piston body 1, ensuring the consistency of the internal depth of the pit 2, facilitating the transitional connection of the joint surfaces between the arc surface structure 5 and the plane structure 6 and the upper top surface 3 of the piston body 1. Additionally, the same depth also avoids the depression at the bottom of the pit 2 and the impact on the gas flow.

[0033] In one embodiment, the arc surface structure 5 and the plane structure 6 are transitioned through a smooth curved surface, and the bottom surface of the pit 2 and the upper top surface 3 of the piston body 1 are transitioned through a smooth curved surface, both of which can further ensure the smoother flow of the mixed gas and improve the thermal efficiency of the engine combustion.

[0034] In one embodiment, referring to Figure 2 , the smooth curved surface where the arc surface structure 5 transitions with the top surface of the piston body 1 is an arc surface, which is set as the first arc surface 7 here. In this embodiment, the radius of the first arc surface 7 is any value within 5 - 10 mm, further ensuring the smooth flow of the mixed gas.

[0035] In one embodiment, referring to Figure 3 , the plane structure 6 is connected to the top surface of the piston body 1 through a transition surface 9. The transition surface 9 is inclined with respect to the upper top surface 3 of the piston body 1. In this embodiment, the included angle between the transition surface 9 and the upper top surface 3 of the piston body 1 is any value between 30° and 45°. The design of this included angle can ensure the space setting of the combustion chamber and optimize the combustion chamber structure, which is beneficial to reducing the center of gravity of the piston body 1 and reducing the swing amplitude of the piston.

[0036] In one embodiment, referring to Figure 3 , second arc surfaces 10 are provided on both sides of the transition surface 9. The second arc surfaces 10 are connected to the plane structure 6 at the bottom of the pit 2 and the upper top surface 3 of the piston body 1, enabling a smooth transition between the transition surface 9, the plane structure 6 at the bottom of the pit 2, and the upper top surface 3 of the piston body 1, ensuring the smoothness of the inner wall of the pit 2 and avoiding the generation of turbulence. Further, the radius of the second arc surface 10 is set to 8 - 10 mm.

[0037] In one embodiment, to ensure the integrity of the entire inner wall of the pit 2, the transition surface 9, the second arc surfaces 10, and the first arc surface 7 are smoothly transitioned to increase the flow rate of the mixed gas.

[0038] In one embodiment, a piston ring is provided at the top of the piston body 1. The piston ring is sleeved on the outer wall of the piston body 1. The ring land above the piston ring is the firing land. The distance between the outer circular surface 8 of the firing land and the junction of the arc surface structure 5 and the upper top surface 3 of the piston body 1 is 10 mm - 15 mm to ensure the overall strength of the top surface of the piston body 1.

[0039] The working principle of the engine piston provided in this embodiment is as follows: During the operation of a methanol engine, the mixed gas enters the recess 2. The mixed gas passes through the arc surface structure 5, which increases the tumble ratio and flow velocity of the mixed gas. Additionally, when the mixed gas flows in the recess 2, in the axial direction of the piston pin, the recess 2 is provided with a planar structure 6. Different from the traditional protruding structure, the planar structure 6 can suppress the generation of gas vortices and affect the combustion speed. Moreover, the arc surface structure 5 and the upper top surface 3 of the piston body 1 are transitionally connected through a first arc surface 7, and the planar structure 6 and the upper top surface 3 of the piston body are transitionally connected through a transition surface 9 and a second arc surface 10, further ensuring smooth gas flow. Furthermore, the inner walls of the recess 2 are smoothly transitionally connected to avoid the generation of protrusions or depressions in the recess 2, reducing friction and further increasing the flow velocity of the mixed gas, thereby accelerating the combustion speed of the engine and enhancing the engine thermal efficiency.

[0040] Embodiment 2

[0041] Different from the above embodiment, this embodiment provides an engine, and this engine is provided with the above engine piston to improve the combustion efficiency of the engine.

[0042] Embodiment 3

[0043] Different from the above embodiment, this embodiment provides a vehicle, and this vehicle is provided with the above engine piston to improve the combustion efficiency of the engine on the vehicle.

[0044] Note that the above is only the preferred embodiment of the present invention and the applied technical principle. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein. Various obvious changes, re-adjustments, and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. An engine piston, comprising a piston body (1), wherein the piston body (1) is provided with a pin hole (4) penetrating a side wall, wherein: The top of the piston body (1) is provided with a recess (2); The bottom surface of the recess (2) is configured as a curved surface structure (5) in the radial direction of the pin hole (4), and the bottom surface of the recess (2) is configured as a plane structure (6) in the horizontal direction of the pin hole (4); the depth of the lowest point of the curved surface structure (5) in the piston body (1) is the same as the depth of the plane structure (6) in the piston body (1); The arc surface structure (5) and the plane structure (6) are transitioned through a smooth curved surface; the bottom surface of the pit (2) and the upper top surface (3) of the piston body (1) are transitioned through a smooth curved surface.

2. The engine piston according to claim 1, characterized in that: The smooth curved surface transitioning between the arc surface structure (5) and the upper top surface (3) of the piston body (1) is configured as an arc surface.

3. The engine piston according to claim 2, characterized in that: A transition surface (9) is arranged between the planar structure (6) and the upper top surface (3) of the piston body (1), and the transition surface (9) is arranged obliquely relative to the top surface of the piston body (1).

4. The engine piston according to claim 3, characterized in that: Second arc surfaces (10) are arranged on both sides of the transition surface (9); the second arc surface (10) is connected to the planar structure (6) and the upper top surface (3) of the piston body (1); and a smooth transition is formed between the transition surface (9), the second arc surface (10) and the arc surface.

5. The engine piston according to claim 1, characterized in that: A piston ring is arranged on the top of the piston body (1), and the piston ring is sleeved on the outer wall of the piston body (1). The annular bank above the piston ring is a fire bank, and the distance between the outer cylindrical surface (8) of the fire bank and the intersection of the arc surface structure (5) and the upper top surface (3) of the piston body (1) is 10mm-15mm.

6. An engine, characterized in that: An engine piston comprising the engine piston according to any one of claims 1 to 5.

7. A vehicle, characterized in that: An engine piston comprising the engine piston according to any one of claims 1 to 6.

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