Asymmetric small-backlash piston structure for reducing CH original row

Abstract

The invention discloses an asymmetric small-backlash piston structure which comprises a piston, a cylinder cover, a cylinder body and a cylinder sleeve. The cylinder cover is installed on the upper portion of the cylinder body. A cylinder hole is formed in the air cylinder body, and the cylinder sleeve is installed in the cylinder hole. The piston is mounted in the cylinder sleeve and comprises a head part, a combustion chamber and a skirt part, the head part is provided with a firepower bank, the combustion chamber is formed in the top surface of the head part, a plurality of piston rings are arranged on the side surface of the head part, and the lower part of the head part is connected with the skirt part; the head portion is of an oval structure, the backlash between the firepower bank and the main thrust face is P, the backlash between the firepower bank and the auxiliary thrust face is Q, the backlash between the firepower bank and the non-thrust face is L, and P > = Q > L. The combustor has the advantages of being high in reliability, capable of reducing fuel entering the backlash space, high in combustion efficiency and the like.

Description

Technical Field

[0001] The invention relates to the technical field of engine pistons, and in particular to an asymmetric small side clearance piston structure for reducing CH primary displacement. Background Art

[0002] The automobile piston is like the central part of the automobile engine, and plays an extremely important role when the engine starts. The automobile piston is used to withstand gas pressure and drive the crankshaft to rotate through the piston pin. The top of the piston is also a part of the combustion chamber. The general automobile piston is divided into three categories: diesel engine piston, gasoline engine piston, and universal piston.

[0003] There is a side clearance between the cylinder head, piston and cylinder liner. Studies have shown that a small side clearance between the piston head and the cylinder liner is conducive to combustion, but thermal expansion and processing deviation during the piston working process lead to abnormal wear, which is not conducive to reliability; a large side clearance between the piston head and the cylinder liner is conducive to wear resistance, but not conducive to combustion. In addition, the side clearance is small and far away from the combustion chamber. When fuel enters the side clearance, the fuel in the side clearance cannot be fully burned, and CH emissions are too high.

[0004] The disclosure of the above background technology content is only used to assist in understanding the concept and technical solution of the present invention. It does not necessarily belong to the prior art of this patent application. In the absence of clear evidence that the above content has been disclosed on the filing date of this patent application, the above background technology should not be used to evaluate the novelty and creativity of the present application. Summary of the invention

[0005] The (main) purpose of the present invention is to provide a piston head with an asymmetric elliptical structure, through which the size of the side clearance space of each part of the piston head is adjusted to achieve the purpose of taking into account both combustion and piston reliability.

[0006] To this end, the present invention proposes an asymmetric small side clearance piston structure for reducing CH primary displacement.

[0007] Preferably, the present invention may also have the following technical features:

[0008] An asymmetric small side clearance piston structure comprises a piston, a cylinder head, a cylinder block and a cylinder liner, wherein the cylinder head is mounted on the upper part of the cylinder block; a cylinder hole is arranged in the cylinder block, and the cylinder liner is mounted in the cylinder hole; the piston is mounted in the cylinder liner, and the piston comprises a head, a combustion chamber and a skirt; the head is provided with a fire bank, the top surface of which is provided with the combustion chamber, the side surface of which is provided with a plurality of piston rings, and the lower part is connected to the skirt; the head is an elliptical structure, wherein the side clearance between the fire bank and the main thrust surface is P, the side clearance between the secondary thrust surface is Q, and the side clearance between the non-thrust surface is L, and P≥Q>L.

[0009] Furthermore, the piston ring closest to the piston top surface is the first piston ring, and the piston head between the first piston ring and the piston top surface is the firing land.

[0010] Furthermore, a sealing ring is assembled inside the first piston ring.

[0011] Furthermore, P>Q.

[0012] Furthermore, the difference between P and Q is 0-0.1 mm.

[0013] Furthermore, the difference between Q and L is 0.1-0.2 mm.

[0014] Furthermore, the head of the piston is an asymmetric elliptical structure, and the two short semi-axes of the ellipse are asymmetric; wherein the two short semi-axes of the asymmetric ellipse are the short semi-axis I and the short semi-axis II, and the length of the short semi-axis I is shorter than the length of the short semi-axis II; the fire shore side corresponding to the short semi-axis I is on the same side as the main thrust surface, forming a side gap P; the fire shore side corresponding to the short semi-axis II is on the same side as the secondary thrust surface, forming a side gap Q.

[0015] The beneficial effects of the present invention compared with the prior art include: in the present invention, by controlling the side clearance values ​​of P, Q, and L, the side clearance of the main thrust surface and the side clearance of the auxiliary thrust surface are larger, thereby ensuring reliability, and the side clearance of the non-thrust surface is small, thereby reducing the fuel from entering the side clearance space, while taking into account combustion efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is an installation schematic diagram of the present invention.

[0017] Figure 2 and Figure 3 It is a schematic diagram of the side clearance between the piston head and the cylinder sleeve of the present invention.

[0018] 1. Cylinder head; 2. Cylinder liner; 3. Piston; 4. Combustion chamber; 5. Side clearance space; 31. Main thrust surface; 32. Secondary thrust surface; 33. Non-thrust surface. DETAILED DESCRIPTION

[0019] The present invention will be further described in detail below in conjunction with specific implementations and with reference to the accompanying drawings. It should be emphasized that the following description is merely exemplary and is not intended to limit the scope of the present invention and its application.

[0020] Non-limiting and non-exclusive embodiments will be described with reference to the following figures, wherein like reference numerals refer to like parts unless otherwise specifically stated.

[0021] like Figures 1 to 3The asymmetric small side clearance piston structure shown in the figure comprises a piston 3, a cylinder head 1, a cylinder block, and a cylinder liner 2, wherein the cylinder head 1 is mounted on the upper part of the cylinder block; a cylinder hole is provided in the cylinder block, and the cylinder liner 2 is installed in the cylinder hole; the piston 3 is installed in the cylinder liner 2; the piston 3 comprises a head, a combustion chamber 4, and a skirt, wherein the head is provided with a fire bank 35, the top surface of which is provided with the combustion chamber 4, the side surface of which is provided with a plurality of piston rings, and the lower part is connected with the skirt 36; the head is an elliptical structure, wherein the side clearance between the fire bank 35 and the main thrust surface 31 is P, the side clearance between the auxiliary thrust surface 32 is Q, and the side clearance between the non-thrust surface 33 is L, and P≥Q>L. In this embodiment, the side clearance of the main thrust surface 31 and the side clearance of the auxiliary thrust surface 32 are large to ensure reliability, and the side clearance of the non-thrust surface 33 is small to reduce fuel ingress and take into account combustion efficiency. More specifically, the piston ring closest to the piston top surface is the first piston ring 37, and the piston head between the first piston ring 37 and the piston top surface is the fire bank 35. During operation, after the first piston ring 37 is equipped with a sealing ring, the sealing ring separates the fire bank 35 from the lower part of the piston head. The piston is an asymmetric side clearance piston.

[0022] Preferably, P>Q, for example, the difference between P and Q is 0-0.1 mm, that is, PQ=0-0.1 mm. The side clearance can avoid or reduce the piston, ensuring smooth back and forth movement of the piston.

[0023] More specifically, the difference between Q and L is 0.1-0.2 mm, that is, QL=0.1-0.2 mm.

[0024] In some embodiments, reference Figures 2-3 The head is an asymmetric ellipse structure, and the two short semi-axes of the asymmetric ellipse are asymmetric; wherein the two short semi-axes of the asymmetric ellipse are the short semi-axes I39 and the short semi-axes II38, and the length of the short semi-axes I39 is shorter than the length of the short semi-axes II38. The firepower shore side corresponding to the short semi-axes I39 is on the same side as the main thrust surface 31; the firepower shore side corresponding to the short semi-axes II38 is on the same side as the secondary thrust surface 32.

[0025] Those skilled in the art will appreciate that numerous variations to the above description are possible, and that the examples and figures are intended only to describe one or more specific implementations.

[0026] Although what is considered as exemplary embodiments of the present invention has been described and described, it will be understood by those skilled in the art that various changes and substitutions may be made thereto without departing from the spirit of the present invention. In addition, many modifications may be made to adapt specific situations to the teachings of the present invention without departing from the central concept of the present invention described herein. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but the present invention may also include all embodiments and their equivalents that fall within the scope of the present invention.

Claims

1. An asymmetric small side clearance piston structure, comprising a piston, a cylinder head, a cylinder block, and a cylinder liner, wherein the cylinder head is mounted on the upper part of the cylinder block; a cylinder hole is provided in the cylinder block, and the cylinder liner is installed in the cylinder hole; the piston is installed in the cylinder liner, and the piston comprises a head, a combustion chamber, and a skirt, wherein the head is provided with a fire land, the top surface of which is provided with the combustion chamber, the side surface of which is provided with a plurality of piston rings, and the lower part is connected to the skirt; characterized in that: The head has an elliptical structure, wherein the side clearance between the fire shore and the main thrust surface is P, the side clearance between the auxiliary thrust surface is Q, and the side clearance between the non-thrust surface is L, and P≥Q>L.

2. An asymmetric small side clearance piston structure as claimed in claim 1, characterized in that: The piston ring closest to the piston top surface is the first piston ring, and the piston head between the first piston ring and the piston top surface is the firing land.

3. An asymmetric small side clearance piston structure as claimed in claim 2, characterized in that: A sealing ring is installed inside the first piston ring.

4. An asymmetric small side clearance piston structure as claimed in claim 1, characterized in that: Said P>Q.

5. An asymmetric small side clearance piston structure as claimed in claim 1, characterized in that: The difference between P and Q is 0-0.1 mm.

6. An asymmetric small side clearance piston structure as claimed in claim 1, characterized in that: The difference between Q and L is 0.1-0.2 mm.

7. An asymmetric small side clearance piston structure as claimed in claim 1, characterized in that: The head of the piston is an asymmetric elliptical structure, and the two short semi-axes of the ellipse are asymmetric; wherein the two short semi-axes of the asymmetric ellipse are the short semi-axis I and the short semi-axis II, and the length of the short semi-axis I is shorter than the length of the short semi-axis II; the fire shore side corresponding to the short semi-axis I is on the same side as the main thrust surface, forming a side gap P; the fire shore side corresponding to the short semi-axis II is on the same side as the secondary thrust surface, forming a side gap Q.

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