Lubricating structure of highly strengthened steel piston of engine

Abstract

The invention discloses an engine high-strengthening steel piston lubricating structure which comprises a piston main cooling structure, and the piston main cooling structure comprises a main cooling cavity, an oil inlet channel and an oil return channel. The main cooling cavity is arranged in the top of a piston, close to a piston ring groove and of an annular cavity structure, and the upper portion of the main cooling cavity is connected with the top of the piston and a combustion chamber and used for absorbing heat transmitted by the wall face of the combustion chamber. The oil inlet channel is parallel to the outer circle of the piston, the upper portion of the oil inlet channel is communicated with the main cooling cavity, the lower portion of the oil inlet channel is communicated with the piston cooling nozzle, and the oil inlet channel is used for guiding external pressure lubricating oil into the main cooling cavity to cool the piston. Under the condition of splash lubrication of the engine, forced lubrication between the piston and the cylinder sleeve, between the piston ring and the cylinder sleeve and between the piston and the piston pin is increased, that is, lubricating oil entering the friction pair has certain pressure, an oil film can be established between the friction pair more quickly, and a better lubrication effect is achieved.

Description

Technical Field

[0001] This invention relates to the field of engine lubrication technology, specifically to a high-strength steel piston lubrication structure for engines. Background Technology

[0002] The piston is a crucial moving and power-transmitting component of an engine. Under the influence of high-temperature, high-pressure combustion gases, the piston continuously reciprocates at high speed, pushing the connecting rod downwards and driving the crankshaft to rotate, thus achieving power output. During piston operation, the piston rings and cylinder liner provide sealing and oil scraping functions. High compressive and tensile loads are transmitted between the piston pin and the piston, and between the connecting rod small-end bushing and the piston pin, with relative movement occurring. The piston also applies a lateral thrust in the radial direction of the cylinder liner. During this process, there are high relative speeds between the piston rings and cylinder liner, and between the piston and cylinder liner. Due to the heat load inside the cylinder, the operating temperatures of the piston rings, the inner wall of the cylinder liner, the piston pin bore, and the outer diameter all exceed 150°C. This results in relatively harsh lubrication conditions among these moving parts—cylinder liner, piston rings, piston, and piston pin—requiring adequate lubrication.

[0003] Currently, most engines use splash lubrication for lubrication between pistons and piston pin bores, cylinder liners and piston rings, and pistons and cylinder liners. As engines develop towards high speed and high power sealing, the thermal and mechanical loads of each friction pair are increasing, and the lubrication requirements are becoming more stringent. Splash lubrication alone is insufficient to establish a stable oil film between friction pairs, and cannot achieve sufficient lubrication and cooling of the friction pairs, which may lead to abnormal wear or even damage to the friction pairs. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the existing defects and provide a high-strength steel piston lubrication structure for engines. Under the conditions of engine splash lubrication, it increases the forced lubrication of piston and cylinder liner, piston ring and cylinder liner, and piston and piston pin. That is, the lubricating oil entering the above friction pairs has a certain pressure, which can establish an oil film between the friction pairs more quickly and achieve better lubrication effect, which can effectively solve the problems in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a high-strength steel piston lubrication structure for an engine, comprising a main piston cooling structure, wherein the main piston cooling structure includes a main cooling chamber, an oil inlet passage, and an oil return passage;

[0006] The main cooling chamber is built into the top of the piston and close to the piston ring groove, and has an annular cavity structure. The upper part of the main cooling chamber connects the top of the piston and the combustion chamber, and is used to absorb the heat transferred from the combustion chamber wall.

[0007] The oil inlet passage is arranged parallel to the outer circle of the piston. The upper part of the oil inlet passage is connected to the main cooling chamber, and the lower part is connected to the piston cooling nozzle. It is used to introduce external pressure lubricating oil into the main cooling chamber to cool the piston.

[0008] The oil return passage is arranged parallel to the outer circle of the piston. The upper part of the oil return passage is connected to the main cooling chamber, and the lower part is connected to the crankcase and oil pan. It is used to allow the lubricating oil that has been cooled to flow into the oil pan through the oil return passage when the engine is running.

[0009] As a preferred embodiment of the present invention, it further includes a piston pin hole forced lubrication structure, which is distributed in the piston pin holes on both sides of the piston inner cavity and includes an inclined oil hole I, which connects the piston pin hole and the main cooling cavity.

[0010] As a preferred embodiment of the present invention, the piston pin hole forced lubrication structure further includes an oil distribution groove, which covers the oil hole of the piston pin hole and has an arc-shaped shallow groove structure.

[0011] As a preferred embodiment of the present invention, it further includes a piston-piston ring and cylinder liner forced lubrication structure, wherein the piston-piston ring and cylinder liner forced lubrication structure is located in the lower part of the piston oil ring groove and is symmetrically distributed along the piston pin hole.

[0012] As a preferred embodiment of the present invention, the piston-piston ring and cylinder liner forced lubrication structure includes an inclined oil hole II, which is obliquely disposed on both sides of the piston pin hole. One end of the inclined oil hole II is connected to the main cooling chamber, and the other end passes through the lower outer circle of the piston oil ring groove and communicates with the outside of the piston.

[0013] As a preferred embodiment of the present invention, it further includes a connecting rod small end bushing lubrication structure, which is located at the piston inner side opening and is perpendicular to the piston pin hole direction, and is symmetrically distributed along the piston pin hole axis.

[0014] As a preferred embodiment of the present invention, the connecting rod small end bushing lubrication structure includes an inclined oil hole III, which is symmetrically distributed on both sides of the piston pin hole. One side of the inclined oil hole III is connected to the main cooling chamber, and the other side passes through the inner wall of the piston and is directly opposite the center of the piston pin hole.

[0015] Compared with the prior art, the beneficial effects of the present invention are: the high-strength steel piston lubrication structure of this engine is reasonably designed and ingeniously conceived. Under the conditions of engine splash lubrication, it increases the forced lubrication of piston and cylinder liner, piston ring and cylinder liner, and piston and piston pin. That is, the lubricating oil entering the above friction pairs has a certain pressure, which can establish an oil film between the friction pairs more quickly, effectively reducing the thermal load on the friction surfaces and preventing overheating and burning. Attached Figure Description

[0016] Figure 1 This is the front view of the present invention;

[0017] Figure 2 for Figure 1 Top view;

[0018] Figure 3 for Figure 2 Sectional view at point AA;

[0019] Figure 4 for Figure 2 Sectional view at point BB;

[0020] Figure 5 for Figure 2 Sectional view at CC;

[0021] Figure 6 for Figure 2 Sectional view at point DD.

[0022] In the diagram: 1 Main cooling chamber, 2 Combustion chamber, 3 Piston ring groove, 4 Oil inlet passage, 5 Oil return passage, 6 Piston pin hole, 7 Oil distribution groove, 8 Inclined oil hole I, 9 Oil ring groove, 10 Inclined oil hole II, 11 Inclined oil hole III. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments (for ease of description and understanding, the following refers to...). Figure 3 (The above is described above). Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of the present invention.

[0024] Please see Figure 1-6 The present invention provides a technical solution: a high-strength steel piston lubrication structure for an engine, including a piston main cooling structure, a piston pin hole forced lubrication structure, a piston-piston ring and cylinder liner forced lubrication structure, and a connecting rod small end bushing lubrication structure.

[0025] The piston main cooling structure includes a main cooling chamber 1, an oil inlet passage 4, and an oil return passage 5. The main cooling chamber 1 is built into the top of the piston and close to the piston ring groove 3, forming an annular cavity structure. The upper part of the main cooling chamber 1 is connected to the piston top and the combustion chamber 2, which is used to absorb the heat transferred from the wall of the combustion chamber 2 and reduce the heat load on the piston head. The outer side of the main cooling chamber 1 is connected to the piston ring groove 3, which is used to absorb the heat in the piston fire shore area, reduce the temperature of the piston ring groove 3, and prevent the piston ring groove 3 from overheating and coking.

[0026] The oil inlet passage 4 is arranged parallel to the outer circle of the piston. The upper part of the oil inlet passage 4 is connected to the main cooling chamber 1, and the lower part is connected to the piston cooling nozzle. It is used to introduce external pressure lubricating oil into the main cooling chamber 1 to cool the piston.

[0027] The oil return passage 5 is arranged parallel to the outer circle of the piston. The upper part of the oil return passage 5 is connected to the main cooling chamber 1, and the lower part is connected to the crankcase and oil pan. It is used to allow the lubricating oil that has been cooled to flow into the oil pan through the oil return passage when the engine is running.

[0028] The piston pin hole forced lubrication structure is distributed in the piston pin holes 6 on both sides of the piston inner cavity, including the inclined oil hole I8 and the oil distribution groove 7.

[0029] Among them, the inclined oil hole I8 connects the piston pin hole 6 and the main cooling chamber 1. One side of the inclined oil hole I8 is connected to the bottom of the main cooling chamber 1, and the other side is connected to the side of the piston pin hole 6. The oil distribution groove 7 covers the oil hole of the piston pin hole 6 and has an arc-shaped shallow groove structure.

[0030] The piston-piston ring and cylinder liner forced lubrication structure is located in the lower part of the piston oil ring groove and is symmetrically distributed along the piston pin hole 6. Two inclined oil holes II10 with a certain included angle are distributed on each side. One end of the inclined oil hole II10 is connected to the main cooling chamber 1, and the other side passes through the lower outer circle of the piston oil ring groove and communicates with the outside of the piston.

[0031] The connecting rod small end bushing lubrication structure is located at the opening on the inner side of the piston and is perpendicular to the direction of the piston pin hole 6. It is symmetrically distributed along the axial direction of the piston pin hole 6, with an inclined oil hole III11 distributed on each side. One side of the inclined oil hole III11 is connected to the main cooling chamber 1, and the other side passes through the inner wall of the piston and is directly opposite the center of the piston pin hole 6.

[0032] During use, the lubricating oil injected into the piston main cooling chamber 1 by the piston cooling nozzle through the oil inlet passage after cooling the piston is supplied to the connecting rod small end bushing, piston ring and cylinder liner, and piston and piston pin respectively, resulting in a high lubricating oil utilization rate.

[0033] As the piston reciprocates at high speed, the lubricating oil injected from the piston cooling nozzle into the piston main cooling chamber 1 from the oil inlet passage generates high-frequency oscillation, and the oil outlet generates high injection pressure, which effectively improves lubrication efficiency. The high-pressure injected lubricating oil is injected into the cylinder liner from the lower part of the oil ring groove, which makes up for the problem of insufficient lubricating oil volume splashed during high-speed operation. At the same time, it is more conducive to the formation of lubricating oil film and improves the lubrication effect of the piston, piston ring and cylinder liner friction pair.

[0034] The high-pressure lubricating oil that enters the piston pin hole 6 through the forced lubrication structure is rapidly distributed in the circumferential direction through the radial oil groove, so that the lubricating oil between the piston pin hole 6 and the piston pin is quickly replenished, the oil film is established more quickly, and the heat generated during the load-bearing process can be dissipated in time. While improving the load-bearing capacity of the piston and piston pin, it effectively reduces the thermal load on the friction surface and prevents overheating and erosion.

[0035] The lubrication structure of the connecting rod small end bushing allows the high-pressure injection of lubricating oil into the connecting rod small end to compensate for the insufficient amount of lubricating oil in splash lubrication, thereby improving the load-bearing capacity of the connecting rod small end bushing and piston pin.

[0036] The parts of the invention not described in detail are prior art. Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-strength steel piston lubrication structure for an engine, characterized in that: It includes a piston main cooling structure, which includes a main cooling chamber (1), an oil inlet passage (4), and an oil return passage (5); The main cooling chamber (1) is built into the top of the piston and close to the piston ring groove (3), and has an annular cavity structure. The upper part of the main cooling chamber (1) is connected to the top of the piston and the combustion chamber (2) to absorb the heat transferred from the wall of the combustion chamber (2). The oil inlet channel (4) is arranged parallel to the outer circle of the piston. The upper part of the oil inlet channel (4) is connected to the main cooling chamber (1), and the lower part is connected to the piston cooling nozzle. It is used to introduce external pressure lubricating oil into the main cooling chamber (1) to cool the piston. The oil return passage (5) is arranged parallel to the outer circle of the piston. The upper part of the oil return passage (5) is connected to the main cooling chamber (1), and the lower part is connected to the crankcase and the oil pan. It is used to allow the lubricating oil that has been cooled to flow into the oil pan through the oil return passage when the engine is running.

2. The high-strength steel piston lubrication structure for an engine according to claim 1, characterized in that: It also includes a piston pin hole forced lubrication structure, which is distributed in the piston pin holes (6) on both sides of the piston inner cavity, including an inclined oil hole I (8), which connects the piston pin hole (6) and the main cooling cavity (1).

3. The engine high-strength steel piston lubrication structure according to claim 2, characterized in that: The piston pin hole forced lubrication structure also includes an oil distribution groove (7), which covers the oil hole of the piston pin hole (6) and has an arc-shaped shallow groove structure.

4. The engine high-strength steel piston lubrication structure according to claim 1, characterized in that: It also includes a piston-piston ring and cylinder liner forced lubrication structure, which is located in the lower part of the piston oil ring groove and is symmetrically distributed along the piston pin hole (6).

5. The engine high-strength steel piston lubrication structure according to claim 4, characterized in that: The piston-piston ring and cylinder liner forced lubrication structure includes an inclined oil hole II (10). The inclined oil hole II (10) is inclinedly arranged on both sides of the piston pin hole (6). One end of the inclined oil hole II (10) is connected to the main cooling chamber (1), and the other side passes through the lower outer circle of the piston oil ring groove and communicates with the outside of the piston.

6. The engine high-strength steel piston lubrication structure according to claim 1, characterized in that: It also includes a connecting rod small end bushing lubrication structure, which is located at the piston inner side opening and perpendicular to the piston pin hole (6), and is symmetrically distributed along the piston pin hole (6) axial direction.

7. The engine high-strength steel piston lubrication structure according to claim 6, characterized in that: The connecting rod small end bushing lubrication structure includes an inclined oil hole III (11), which is symmetrically distributed on both sides of the piston pin hole (6). One side of the inclined oil hole III (11) is connected to the main cooling chamber (1), and the other side passes through the inner wall of the piston and is directly opposite the center of the piston pin hole (6).

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