An efficient heat dissipation diesel engine piston combustion chamber and combustion control method

Abstract

The present invention discloses a diesel engine piston combustion chamber with efficient heat dissipation, which comprises a piston body. A combustion chamber is arranged at the top of the piston body, a ring groove is arranged on the outer side, and an annular cooling oil passage is further arranged inside. The combustion chamber comprises an upper combustion chamber, a lower combustion chamber and a throat. The throat is arranged between the upper combustion chamber and the lower combustion chamber, and the throat is located at the middle position of the combustion chamber, so that the heights of the upper combustion chamber and the lower combustion chamber are equal or approximately equal. The present invention has the advantages of reliable structure, efficient cooling, and improved service life of the piston, etc.

Description

Technical Field

[0001] The present invention relates to the technical field of engine pistons, and particularly to a diesel engine piston combustion chamber with efficient heat dissipation and a combustion control method. Background Art

[0002] The in-cylinder combustion explosion pressure of diesel engines is continuously increasing, and the combustion temperature is very high. However, the vast majority of combustion chambers still retain the design of a deep omega shape, with the piston throat located on the piston top surface. Due to the limitation of the deep combustion chamber, the layout position of the piston annular cooling oil channel (horizontally arranged) is relatively low, far from the piston throat (the highest combustion temperature area) and the first and second ring grooves. It is extremely easy for the throat to crack due to poor cooling, and the high temperature in the first and second piston ring groove lands causes oil carbon deposition, resulting in ring sticking failures.

[0003] The existing patent document CN217270512 cools the throat by adding a small cooling oil channel near the throat. This not only places higher requirements on the piston production process but also affects the overall structural strength of the piston.

[0004] The disclosure of the above background art content is only used to assist in understanding the concept and technical solution of the present invention, and it does not necessarily belong to the prior art of this patent application. Without clear evidence indicating that the above content was publicly available on the filing date of this patent application, the above background art should not be used to evaluate the novelty and inventiveness of this application. Summary of the Invention

[0005] The purpose of the present invention is to provide a diesel engine piston combustion chamber with efficient heat dissipation and a combustion control method that has a reliable structure, high cooling efficiency, and can extend the service life of the piston.

[0006] To this end, the present invention provides a diesel engine piston combustion chamber with efficient heat dissipation and a combustion control method.

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

[0008] A diesel engine piston combustion chamber with efficient heat dissipation includes a piston body. A combustion chamber is provided at the top of the piston body, ring grooves are provided on the outer side, and an annular cooling oil channel is also provided inside. The combustion chamber includes an upper combustion chamber, a lower combustion chamber, and a throat. The throat is provided between the upper combustion chamber and the lower combustion chamber, and the throat is located in the middle of the combustion chamber, making the heights of the upper combustion chamber and the lower combustion chamber equal or approximately equal.

[0009] Furthermore, the combustion chamber is an eccentric combustion chamber.

[0010] Furthermore, the upper combustion chamber is trumpet-shaped, and it expands in a trumpet shape from the throat to the top surface of the piston body.

[0011] Further, the annular cooling oil passage is arranged in an inclined manner, and the annular cooling oil passage is also provided with an oil inlet and an oil outlet.

[0012] Further, the side of the oil inlet is lower and the side of the oil outlet is higher.

[0013] Further, the lowest point of the lower side of the annular cooling oil passage is within the height range of the third ring groove, and the highest point is below the first ring groove; the lowest point of the higher side of the annular cooling oil passage is above the third ring groove, and the highest point is below the first ring groove.

[0014] Further, the inclination angle of the annular cooling oil passage is 0.5 - 2°.

[0015] Further, the inclination angle of the annular cooling oil passage is 1 - 1.5°.

[0016] A combustion control method for a diesel engine piston combustion chamber with high - efficiency heat dissipation, including the above - mentioned combustion chamber, spraying fuel at the throat, so that the fuel forms vortices in the upper combustion chamber and the lower combustion chamber respectively.

[0017] The beneficial effects of the present invention compared with the prior art include: by setting the throat at half of the depth of the combustion chamber, on the one hand, it can be closer to the annular cooling oil passage, which is beneficial to the rapid heat dissipation of the throat and reduces the problem of cracking of the throat due to high temperature; on the other hand, after the fuel is injected into the throat of the combustion chamber, it flips upward and downward into the upper combustion chamber and the lower combustion chamber and mixes with air, and then vortices are generated in the upper combustion chamber and the lower combustion chamber respectively, enabling the air and fuel to be fully mixed, which is more conducive to combustion. Setting the oil inlet on the side with a lower horizontal height of the annular cooling oil passage and the oil outlet on the relatively higher side is beneficial to the rapid flow of the cooling oil to dissipate heat from the piston and the piston ring grooves, and reduces the coking and carbon deposition of the oil. Brief Description of the Drawings

[0018] Figure 1 is a cross - sectional view of the present invention.

[0019] Figure 2 is a top view of the present invention.

[0020] Figure 3 is a schematic diagram of the combustion chamber vortex of the present invention, and the arrow direction represents two vortex states of the oil spraying upward and downward after being sprayed at the throat. Detailed Description of the Invention

[0021] The present invention will be further described in detail below in conjunction with the specific embodiments and with reference to the accompanying drawings. It should be emphasized that the following description is merely exemplary and not intended to limit the scope of the present invention and its applications.

[0022] Referring to the following drawings, non - restrictive and non - exclusive embodiments will be described, where the same reference numerals represent the same components unless otherwise specifically stated.

[0023] As Figures 1 to 3 shown, a diesel engine piston combustion chamber with efficient heat dissipation includes a piston body 5. A combustion chamber 8 is provided at the top of the piston body 5, a ring groove is provided on the outside, and an annular cooling oil passage 4 is also provided inside. The combustion chamber 8 includes an upper combustion chamber 3, a lower combustion chamber 1, and a throat 2. The throat 2 is provided between the upper combustion chamber 3 and the lower combustion chamber 1 and is the demarcation point between the upper combustion chamber 3 and the lower combustion chamber 1. The throat 2 is located at the middle position of the combustion chamber 8, making the heights of the upper combustion chamber 3 and the lower combustion chamber 1 equal or approximately equal. Compared with the prior art in which the throat is provided at a relatively upper position, in this embodiment, the throat 2 is provided at a position half of the depth of the combustion chamber 8. On the one hand, it can be closer to the annular cooling oil passage 4, which is beneficial to the rapid heat dissipation of the throat 2 and reduces the problem of cracking of the throat 2 due to high temperature. On the other hand, after the fuel is injected at the throat 2 of the combustion chamber 8, it flips upward into the upper combustion chamber 3 and the lower combustion chamber 1 and mixes with air, and then vortices are respectively generated in the upper combustion chamber 3 and the lower combustion chamber 1, forming a double vortex inside the combustion chamber 8, enabling the air and fuel to be fully mixed and being more conducive to combustion. For most existing combustion chambers, due to the too high position of the throat, the space of the upper combustion chamber is limited and it is difficult to form an effective vortex to promote combustion. Preferably, the combustion chamber is an eccentric combustion chamber.

[0024] Specifically, the upper combustion chamber 3 is in the shape of a large horn, which expands from the throat 2 to the top surface of the piston body 5 like a horn mouth, guiding the burned exhaust gas to quickly conduct heat transfer to the bottom of the cylinder head, reducing the heat absorption time of the piston and accelerating cooling. The lower combustion chamber is in a shallow ω shape.

[0025] In a further improvement of the above technical solution, the annular cooling oil passage 4 is arranged in an inclined manner, and the annular cooling oil passage 4 is also provided with an oil inlet and an oil outlet. Among them, the oil inlet side is lower and the oil outlet side is higher. The oil inlet is arranged on the side with a lower horizontal height of the annular cooling oil passage 4, and the oil outlet is arranged on the relatively higher side, which is beneficial to the rapid flow of the cooling oil to dissipate heat from the piston and the piston ring groove, reducing the coking and carbon deposition of the oil. Preferably, the lowest point of the lower side of the annular cooling oil passage 4 is within the height range of the third ring groove 6, and the highest point is below the first ring groove 7; the lowest point of the higher side of the annular cooling oil passage is above the third ring groove 6, and the highest point is below the first ring groove 7.

[0026] Furthermore, the inclination angle of the annular cooling oil passage 4 is 0.5 - 2°, such as 0.5°, 1°, 1.5°, 2°, etc. Reasonably adjusting the inclination angle of the annular cooling oil passage 4, too large deviation of the inclination angle will affect the cooling uniformity of the ring groove.

[0027] A combustion control method for a diesel engine piston combustion chamber with efficient heat dissipation includes the above-mentioned combustion chamber 8, and the fuel is sprayed at the throat 2, so that vortices are respectively formed in the upper combustion chamber 3 and the lower combustion chamber 1.

[0028] Those skilled in the art will recognize that numerous variations to the above description are possible, so the embodiments and the figures are only used to describe one or more specific embodiments.

[0029] Although the exemplary embodiments considered to be the present invention have been described and recited, those skilled in the art will understand that various changes and substitutions can be made thereto without departing from the spirit of the present invention. Additionally, many modifications can be made to adapt a particular situation 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 within the scope of the present invention and their equivalents.

Claims

1. An efficient heat dissipation diesel engine piston combustion chamber, comprising a piston body, a combustion chamber is provided at the top of the piston body, a ring groove is provided on the outer side, and an annular cooling oil passage is further provided inside. The combustion chamber includes an upper combustion chamber, a lower combustion chamber, and a throat. The throat is provided between the upper combustion chamber and the lower combustion chamber, and is characterized in that: The throat is located at the middle position of the combustion chamber, making the heights of the upper combustion chamber and the lower combustion chamber equal; The combustion chamber is an eccentric combustion chamber; The annular cooling oil passage is arranged in an inclined manner, and the annular cooling oil passage is also provided with an oil inlet and an oil outlet; The side of the oil inlet is lower and the side of the oil outlet is higher; The lowest point of the lower side of the annular cooling oil passage is within the height range of the third ring groove, and the highest point is below the first ring groove; the lowest point of the higher side of the annular cooling oil passage is above the third ring groove, and the highest point is below the first ring groove.

2. The high-efficiency heat-dissipating diesel engine piston combustion chamber according to claim 1, characterized in that: The upper combustion chamber is trumpet-shaped, and it expands in a trumpet shape from the throat to the top surface of the piston body.

3. An efficient heat dissipation diesel engine piston combustion chamber according to claim 1, characterized in that: The inclination angle of the annular cooling oil passage is 0.5 - 2°; 4. The highly efficient heat dissipating diesel engine piston combustion chamber according to claim 3, wherein: The inclination angle of the annular cooling oil passage is 1 - 1.5°; 5. A combustion control method for a diesel engine piston combustion chamber with high-efficiency heat dissipation, including the combustion chamber described in claim 1, characterized in that: Fuel is sprayed at the throat, so that fuel vortices are formed in the upper combustion chamber and the lower combustion chamber respectively.

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