Piston cooling system, crankcase and vehicle

Abstract

This invention discloses a piston cooling system, a crankcase, and a vehicle, relating to the field of engine cooling and lubrication technology. The piston cooling system includes a piston body, an oil pan, an oil pump, and an oil collecting component. The piston body reciprocates within a cylinder liner, which includes an oil inlet passage. The piston body includes an inner cooling oil jacket and an opening. The inner cooling oil jacket includes an oil inlet and an oil outlet. The oil inlet communicates with the oil inlet passage, and the oil outlet communicates with the opening. A partition plate is provided in the oil pan to divide its inner cavity into a first oil storage area and a second oil storage area. The partition plate has a connecting hole. The oil pump pumps oil from the first oil storage area to the oil inlet passage. The oil collecting component includes an inlet and an outlet that communicate with each other. The inlet is located at the bottom of the opening, and the outlet is located at the top of the second oil storage area. This piston cooling system distinguishes between high-temperature and low-temperature engine oil, eliminating the need for an oil cooler and thus reducing the overall production cost of the piston cooling system.

Description

Technical Field

[0001] This invention relates to the field of engine cooling and lubrication technology, and particularly to a piston cooling system, crankcase, and vehicle. Background Technology

[0002] When a car engine is running, the combustion of the combustible mixture in the combustion chamber generates a large amount of heat. The combustion chamber is a space enclosed by the cylinder head, cylinder liner, and piston. Both the cylinder head and cylinder liner have cooling water jackets inside, with continuously circulating cooling water to cool them and prevent overheating that could cause deformation or damage. Because the piston moves in a high-speed reciprocating motion, and the piston head is in direct contact with the inside of the combustion chamber, the piston head temperature is particularly high. Generally, oil is sprayed into the piston bottom cavity through piston cooling nozzles to reduce the piston top temperature and prevent piston damage.

[0003] Currently, piston cooling nozzles (PCJs) are generally installed on one side of the engine block. The PCJ oil passage is connected to the main engine oil passage. Lubricating oil at a certain pressure is sprayed into the piston bottom cavity through the PCJ. The sprayed pressurized oil forms a mist at the nozzle orifice, and the fan-shaped oil mist is sprayed into the piston bottom cavity. The piston bottom cavity and the piston top are separated by only a certain wall thickness. The sprayed oil can cool the piston top, and the oil temperature rises after being sprayed into the piston bottom and returns to the oil pan. After lubrication of other parts, the oil also returns to the oil pan. Then, the two types of oil mix and the overall oil temperature rises. Especially under heavy engine load conditions, it is necessary to install an oil cooler on the oil passage to cool the oil before it goes to the main engine oil passage to lubricate various oil-using parts. This increases the cost of the entire system and also increases the flow resistance of the system. Especially during cold starts, the oil temperature is low, the oil viscosity is high, and the flow resistance of the oil cooler is very large.

[0004] Therefore, it is necessary to provide a new piston cooling system, crankcase, and vehicle to solve the aforementioned technical problems. Summary of the Invention

[0005] The main objective of this invention is to provide a piston cooling system, crankcase, and vehicle, which aims to improve the technical problems of high cost and high flow resistance in existing piston cooling systems.

[0006] To achieve the above objectives, the present invention proposes a piston cooling system, the piston cooling system comprising:

[0007] A piston body reciprocates up and down within a cylinder liner. The cylinder liner includes an oil inlet passage. The piston body includes an internal cooling oil sleeve and an opening. The internal cooling oil sleeve includes an oil inlet and an oil outlet. The oil inlet is used to communicate with the oil inlet passage, and the oil outlet is used to communicate with the opening.

[0008] An oil pan, wherein a partition plate is provided in the oil pan to divide the inner cavity of the oil pan into a first oil storage area and a second oil storage area, and the partition plate is formed with a connecting hole;

[0009] An oil pump, the oil pump being used to pump oil from the first oil reservoir to the oil inlet passage;

[0010] An oil collecting component includes an inlet and an outlet that are interconnected, the inlet being located at the bottom of the opening and the outlet being located at the top of the second oil storage area.

[0011] In one embodiment, the outer surface of the oil pan is provided with a plurality of heat dissipation fins, which are disposed on the side close to the second oil storage area.

[0012] In one embodiment, the second oil storage area is positioned on the windward side of the vehicle.

[0013] In one embodiment, the diameter of the oil inlet channel is larger than the diameter of the oil inlet port.

[0014] In one embodiment, there are multiple oil inlet passages, which are arranged at intervals along the vertical direction on the cylinder liner.

[0015] In one embodiment, a gap is formed between the outer side of the piston body and the cylinder liner, and the gap is filled with engine oil to form an oil film.

[0016] In one embodiment, a first annular groove is provided on the outer surface of the top of the piston body, and the piston cooling system further includes a first piston ring, which is engaged in the first annular groove and extends out of the piston body, and contacts the inner wall of the cylinder liner.

[0017] In one embodiment, a second annular groove is further provided on the outer surface of the top of the piston body. The second annular groove is located at the bottom of the first annular groove. The piston cooling system further includes a second piston ring, which is engaged in the second annular groove and extends out of the piston body. The second piston ring contacts the inner wall of the cylinder liner.

[0018] In one embodiment, the oil inlet passage is inclined toward the piston body, and the internal cooling oil jacket includes a first connecting section, a second connecting section, and a third connecting section connected in sequence. The first connecting section is inclined, the second connecting section is horizontal, the first connecting section is connected to the oil inlet passage, and the third connecting section is connected to the opening.

[0019] In one embodiment, the piston cooling system further includes a main oil passage, a solenoid valve, and an injection oil passage connected in sequence. The oil pump is used to pump oil from the first oil reservoir to the main oil passage, and the injection oil passage is connected to the oil inlet passage.

[0020] In one embodiment, the piston cooling system further includes a first lubrication component and a second lubrication component, one end of which is connected to the main oil passage, the other end of which is connected to the first oil storage area, and the other end of which is connected to the second oil storage area.

[0021] The present invention also provides a crankcase, including a cylinder block, a cylinder head and the piston cooling system described above, wherein the oil pan, the cylinder block and the cylinder head form the inner cavity of the crankcase, and the bottom of the piston block is provided with a cavity that communicates with the opening, the cavity being in communication with the inner cavity.

[0022] The present invention also provides a vehicle including the piston cooling system described above; or the crankcase described above.

[0023] In the above scheme, the piston cooling system includes a piston body, an oil pan, an oil pump, and an oil collecting component. The piston body reciprocates up and down within the cylinder liner. The cylinder liner includes an oil inlet passage. The piston body includes an internal cooling oil jacket and an opening. The internal cooling oil jacket includes an oil inlet and an oil outlet. The oil inlet communicates with the oil inlet passage, and the oil outlet communicates with the opening. A partition plate is provided in the oil pan to divide the inner cavity of the oil pan into a first oil storage area and a second oil storage area. The partition plate forms a connecting hole. The oil pump pumps the oil in the first oil storage area to the oil inlet passage. The oil collecting component includes an inlet and an outlet that communicate with each other. The inlet is located at the bottom of the opening, and the outlet is located at the top of the second oil storage area. Specifically, when the engine is running, the engine load determines whether piston cooling is needed. When the engine load exceeds a threshold, the oil pump delivers oil to the inlet passage. When the piston moves vertically downwards within the cylinder liner and is at bottom dead center, the inlet of the inner cooling oil jacket connects to the inlet passage, allowing oil to be sprayed into and fill the entire inner cooling oil jacket to cool the top of the piston. The oil in the inner cooling oil jacket absorbs heat from the top of the piston, causing the oil temperature to rise. As the piston moves upwards from bottom dead center, the inlet of the inner cooling oil jacket is misaligned with the inlet passage, preventing oil from entering the inner cooling oil jacket. The oil in the inner cooling oil jacket then flows out from the outlet to the opening, from the opening to the inlet of the oil collection component, and then from the outlet of the oil collection component into the second oil storage area of ​​the oil pan. This process collects the high-temperature oil and cools the oil in other oil-using components of the engine. All engine oil returns to the first oil reservoir through a dedicated return channel. High-temperature engine oil is then cooled separately in the second oil reservoir. When the piston needs cooling, the oil pump draws low-temperature engine oil from the first reservoir and repeats the above steps to cool the top of the piston. The high-temperature engine oil, after cooling in the second oil reservoir 23, then enters the first reservoir through the connecting hole. Therefore, in this invention, high-temperature and low-temperature engine oils are separated. The high-temperature oil reservoir is located on the windward side of the vehicle and has cooling fins, increasing the heat dissipation efficiency of the high-temperature engine oil. This eliminates the need for an oil cooler in the entire piston cooling system to cool the oil pumped by the oil pump, thus saving on the cost of an oil cooler and reducing the overall production cost of the piston cooling system. Furthermore, eliminating the need for an oil cooler reduces the flow resistance of the piston cooling system. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of a piston cooling system according to an embodiment of the present invention;

[0026] Figure 2 A schematic diagram of the connection between the piston body and cylinder liner according to an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of an embodiment of the oil pan provided by the present invention.

[0028] Description of Figure Numbers:

[0029] 100. Piston cooling system; 1. Piston body; 2. Oil pan; 3. Oil collecting component; 4. Oil suction plate; 5. Cylinder liner; 51. Oil inlet passage; 11. Internal cooling oil jacket; 12. Opening; 111. Oil inlet; 112. Oil outlet; 21. Divider plate; 22. First oil storage area; 23. Second oil storage area; 211. Connecting hole; 31. Inlet; 32. Outlet; 6. Clearance; 13. First annular groove; 14. Second annular groove; 113. First connecting section; 114. Second connecting section; 115. Third connecting section; 100a. Main oil passage; 100b. Solenoid valve; 100c. Injection oil passage; 100d. First lubrication assembly; 100e. Second lubrication assembly.

[0030] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0031] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0032] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0033] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0034] When a car engine is running, the combustion of the combustible mixture in the combustion chamber generates a large amount of heat. The combustion chamber is a space enclosed by the cylinder head, cylinder liner, and piston. Both the cylinder head and cylinder liner have cooling water jackets inside, with continuously circulating cooling water to cool them and prevent overheating that could cause deformation or damage. Because the piston moves in a high-speed reciprocating motion, and the piston head is in direct contact with the inside of the combustion chamber, the piston head temperature is particularly high. Generally, oil is sprayed into the piston bottom cavity through piston cooling nozzles to reduce the piston top temperature and prevent piston damage.

[0035] Currently, piston cooling nozzles (PCJs) are generally installed on one side of the engine block. The PCJ oil passage is connected to the main engine oil passage. Lubricating oil at a certain pressure is sprayed into the piston bottom cavity through the PCJ. The sprayed pressurized oil forms a mist at the nozzle orifice, and the fan-shaped oil mist is sprayed into the piston bottom cavity. The piston bottom cavity and the piston top are separated by only a certain wall thickness. The sprayed oil can cool the piston top, and the oil temperature rises after being sprayed into the piston bottom and returns to the oil pan. After lubrication of other parts, the oil also returns to the oil pan. Then, the two types of oil mix and the overall oil temperature rises. Especially under heavy engine load conditions, it is necessary to install an oil cooler on the oil passage to cool the oil before it goes to the main engine oil passage to lubricate various oil-using parts. This increases the cost of the entire system and also increases the flow resistance of the system. Especially during cold starts, the oil temperature is low, the oil viscosity is high, and the flow resistance of the oil cooler is very large.

[0036] Please see Figures 1 to 3This invention proposes a piston cooling system 100, which includes a piston body 1, an oil pan 2, an oil pump, and an oil collecting component 3. The piston body 1 reciprocates up and down within a cylinder liner 5. The cylinder liner 5 includes an oil inlet passage 51. The piston body 1 includes an inner cooling oil jacket 11 and an opening 12. The inner cooling oil jacket 11 includes an oil inlet 111 and an oil outlet 112. The oil inlet 111 communicates with the oil inlet passage 51, and the oil outlet 112 communicates with the opening 12. A partition plate 21 is provided in the oil pan 2 to divide the inner cavity of the oil pan 2 into a first oil storage area 22 and a second oil storage area 23. The partition plate 21 forms a connecting hole 211. The oil pump pumps the oil in the first oil storage area 22 to the oil inlet passage 51. The oil collecting component 3 includes an inlet 31 and an outlet 32 ​​that communicate with each other. The inlet 31 is located at the bottom of the opening 12, and the outlet 32 ​​is located at the top of the second oil storage area 23.Specifically, for a four-stroke engine, there are four strokes: intake, compression, power, and exhaust. During the intake and power strokes, the piston 1 moves downwards, while during the compression and exhaust strokes, it moves upwards. When the engine is running, the engine load determines whether cooling of the piston 1 is necessary. When the engine load exceeds a threshold, the oil pump delivers oil to the oil inlet passage 51. When the piston 1 moves vertically downwards within the cylinder liner 5 and is at bottom dead center, the oil inlet 111 of the inner cooling oil jacket 11 of the piston 1 connects with the oil inlet passage 51, and oil is sprayed into the inner cooling oil jacket. The oil in the inner cooling oil jacket 11 is filled to cool the top of the piston body 1. The oil in the inner cooling oil jacket 11 absorbs the heat from the top of the piston body 1, causing the oil to heat up. As the piston body 1 continues to move upward from the bottom dead center, the oil inlet 111 of the inner cooling oil jacket 11 is misaligned with the oil inlet passage 51. At this time, the oil cannot enter the inner cooling oil jacket 11, and the oil in the inner cooling oil jacket 11 flows out from the oil outlet 112 to the opening 12, then from the opening 12 to the inlet 31 of the oil collecting component 3, and then from the outlet 32 ​​of the oil collecting component 3 into the second oil storage area 23 of the oil pan 2. The high-temperature engine oil is collected, while the low-temperature engine oil from other oil-using components returns to the first oil reservoir 22 through a dedicated return channel. The high-temperature oil then undergoes self-cooling in the second oil reservoir 23. When cooling of the piston block 1 is needed later, the oil pump draws low-temperature engine oil from the first reservoir and repeats the above steps to cool the top of the piston block 1. After the high-temperature engine oil cools in the second oil reservoir 23, the oil pump draws oil, causing the oil level in the first oil reservoir 22 to drop. Due to the U-tube principle, the oil in the second oil reservoir 23 replenishes the first oil reservoir 22, maintaining the oil level in the first reservoir. When the oil levels in oil zone 22 and the second oil storage zone 23 are the same, the engine oil in the second oil storage zone 23 will enter the first storage zone through the connecting hole 211. Therefore, in this embodiment, high-temperature engine oil and low-temperature engine oil are distinguished. In this way, there is no need to install an oil cooler in the entire piston cooling system 100 to cool the engine oil pumped by the oil pump. This saves the cost of the oil cooler, thereby reducing the production cost of the entire piston cooling system 100. At the same time, by eliminating the oil cooler, the engine oil does not need to flow through the oil cooler for cooling, which reduces the flow resistance of the piston cooling system 100.

[0037] Please see Figure 1 and Figure 3Furthermore, the piston cooling system 100 also includes an oil suction plate 4. One end of the oil suction plate 4 is connected to one end of the oil pump, and the other end is connected to the oil pan 2. The oil suction plate 4 is mainly used to collect and store the engine oil in the engine oil pan 2. When the engine is running, the engine oil is delivered by the oil pump to various components that require lubrication, such as the crankshaft, connecting rod bearings, camshaft, and piston body 1. After the lubricating oil has completed its lubrication task, it flows back to the oil pan 2 located at the bottom of the engine by gravity, and is then sucked in by the oil suction plate 4. The oil suction plate 4 has a built-in filter or magnetic insert, which can adsorb metal shavings and other impurities in the lubricating oil, reducing the wear of these impurities on the internal parts of the engine. The oil suction plate 4 also helps to keep the inside of the engine clean and prevent sludge and other deposits from affecting engine performance.

[0038] In one embodiment, the outer surface of the oil pan 2 is provided with multiple heat dissipation fins, which are located on the side near the second oil storage area 23. Specifically, the heat from the high-temperature engine oil is transferred to the surface of the oil pan 2, and then the heat is conducted to the heat dissipation fins. The heat dissipation fins are usually made of materials with good thermal conductivity, such as copper or aluminum, to ensure that heat can be quickly transferred from the heat source to the heat dissipation fins. The heat dissipation fins increase the surface area in contact with the surrounding air, which makes it easier for heat to be transferred to the surrounding air by convection. Under natural convection, hotter air rises, while cooler surrounding air flows in to fill the gaps, creating airflow. This improves cooling efficiency, allowing the high-temperature engine oil in the second oil reservoir 23 to cool down more quickly. The cooling fins increase heat dissipation efficiency by increasing surface area; more surface area means more heat can be transferred to the surrounding environment more quickly. Because the design of the cooling fins promotes airflow, both natural and forced convection effectively improve heat dissipation efficiency. Compared to other complex cooling solutions, cooling fins are a relatively simple and low-cost method. Cooling fins typically have a simple structure, are easy to clean and maintain, do not require an additional power source to operate, reducing the possibility of failure, and because they have no moving parts, they are highly reliable and not easily damaged.

[0039] In one embodiment, the second oil reservoir 23 is positioned on the windward side of the vehicle. Specifically, by positioning the second oil reservoir 23 on the windward side of the vehicle, when the vehicle is in motion, the high-temperature engine oil in the second oil reservoir 23 transfers heat to the oil pan 2, and then the airflow in the direction of the vehicle's front cools the oil pan 2, thereby cooling the high-temperature engine oil in the second oil reservoir 23. This also allows the high-temperature engine oil in the second oil reservoir 23 to cool down more quickly.

[0040] Furthermore, the second oil storage area 23 is located on the windward side of the vehicle, and multiple cooling fins are provided on the outer surface of the oil pan 2 near the second oil storage area 23. The second oil storage area 23 of the oil pan 2 with cooling fins is cooled by the airflow from the front of the vehicle. By increasing the airflow on the cooling fins, the cooling efficiency of the second oil storage area 23 can be further improved.

[0041] In one embodiment, the diameter of the oil inlet channel 51 is larger than the diameter of the oil inlet port 111. Specifically, when the engine is running, the engine load determines whether cooling of the piston body 1 is necessary. When the engine load exceeds a threshold, the oil pump pumps oil to the oil inlet passage 51. When the piston body 1 moves vertically downward in the cylinder liner 5 and is at the bottom dead center, the oil inlet 111 of the inner cooling oil jacket 11 of the piston body 1 is connected to the oil inlet passage 51. Oil is then sprayed into the inner cooling oil jacket 11 and fills the entire inner cooling oil jacket 11 to cool the top of the piston body 1. The oil in the inner cooling oil jacket 11 absorbs the heat from the top of the piston body 1, and the oil temperature rises. Since the diameter of the oil inlet passage 51 is larger than that of the oil inlet 111, when the piston body 1 continues to move upward from the bottom dead center, the oil inlet passage 51 will remain connected to the oil inlet 111 for a period of time. This continuously fills the inner cooling oil jacket 11 of the piston body 1 with oil, ensuring that the inner cooling oil jacket 11 is filled with oil and ensuring the cooling effect of the piston body 1.

[0042] In one embodiment, there are multiple oil inlet passages 51, which are arranged at intervals along the vertical direction on the cylinder liner 5. Specifically, when the engine is running, the engine load determines whether the piston body 1 needs to be cooled. When the engine load exceeds the threshold, the oil pump pumps oil to the oil inlet passage 51. When the piston body 1 moves vertically downward in the cylinder liner 5 and is at the bottom dead center, the oil inlet 111 of the inner cooling oil jacket 11 of the piston body 1 is connected to the oil inlet passage 51. The oil is then sprayed into the inner cooling oil jacket 11 and fills the entire inner cooling oil jacket 11 to cool the top of the piston body 1. The oil in the inner cooling oil jacket 11 absorbs the heat from the top of the piston body 1, and the oil temperature rises. As the piston body 1 continues to move upward from the bottom dead center, when the piston body 1 moves to the point where the oil inlet 111 is connected to another oil inlet passage 51, the inner cooling oil jacket 11 can continue to be filled with oil. After multiple injections of oil into the inner cooling oil jacket 11, it is ensured that the inner cooling oil jacket 11 is filled with oil, thereby achieving the effect of cooling the piston body 1.

[0043] Please see Figure 1 and Figure 2In one embodiment, a gap 6 is formed between the outer side of the piston body 1 and the cylinder liner 5, and the gap 6 is filled with engine oil to form an oil film. Specifically, since a gap 6 is formed between the outer side of the piston body 1 and the cylinder liner 5, when engine oil is injected into the oil inlet 111 through the oil inlet passage 51, some engine oil will flow into the gap 6. In this way, the engine oil will form an oil film in the gap 6. When the piston body 1 reciprocates up and down in the cylinder, the oil film can lubricate the reciprocating motion of the piston body 1, ensuring the normal movement of the piston body 1. At the same time, the oil film can also form a certain sealing effect between the piston body 1 and the cylinder liner 5.

[0044] Please see Figure 1 and Figure 2 In one embodiment, a first annular groove 13 is provided on the outer surface of the top of the piston body 1. The piston cooling system 100 also includes a first piston ring, which is engaged in the first annular groove 13 and extends out of the piston body 1, contacting the inner wall of the cylinder liner 5. The top of the piston body 1 is close to the combustion chamber, which generates high-temperature and high-pressure gas during operation. This high-temperature and high-pressure gas can affect the components below the piston body 1, so it is necessary to seal these gases to prevent leakage. In this embodiment, a first annular groove 13 is provided on the top of the piston body 1, and the first piston ring is engaged in the first annular groove 13, with the first piston ring contacting the inner wall of the cylinder liner 5. In this way, the first piston ring seals the space above the piston body 1, preventing the leakage of high-temperature and high-pressure gas.

[0045] Please see Figure 1 and Figure 2 In one embodiment, a second annular groove 14 is provided on the outer surface of the top of the piston body 1. The second annular groove 14 is located at the bottom of the first annular groove 13. The piston cooling system 100 also includes a second piston ring, which is engaged in the second annular groove 14 and extends out of the piston body 1. The second piston ring contacts the inner wall of the cylinder liner 5. Specifically, the second annular groove 14 is provided on the piston body 1, the second piston ring is engaged in the second annular groove 14, and the second piston ring contacts the inner wall of the cylinder liner 5. The engine oil forms an oil film in the gap 6 formed between the outer side of the piston body 1 and the cylinder liner 5. When the piston body 1 moves downward, the oil film lubricates the movement of the piston body 1. At the same time, the second piston ring scrapes off the oil film, thus preventing engine oil from entering the top of the piston body 1, i.e., preventing engine oil from entering the combustion chamber and burning, which would otherwise lead to high oil consumption.

[0046] Please see Figure 1 and Figure 2Furthermore, there are multiple second annular grooves 14, which are spaced apart in the vertical direction. There are also multiple second piston rings, and the number of second piston rings and the number of second annular grooves 14 are equal and correspond one-to-one. When the piston body 1 moves downward, the multiple second piston rings will scrape the oil film out in sequence. This arrangement of multiple second piston rings can further improve the oil film scraping efficiency.

[0047] Please see Figure 1 and Figure 2 In one embodiment, the oil inlet passage 51 is inclined toward the piston body 1. The internal cooling oil jacket 11 includes a first connecting section 113, a second connecting section 114, and a third connecting section 115 connected in sequence. The first connecting section 113 is inclined, and the second connecting section 114 is horizontal. The first connecting section 113 communicates with the oil inlet passage 51, and the third connecting section 115 communicates with the opening 12. By inclining the oil inlet passage 51 toward the piston body 1, compared to setting the oil inlet passage 51 horizontally, in this embodiment, the oil inlet passage is inclined toward the piston body 1. This ensures that when the oil pump pumps oil into the internal cooling oil jacket 11, the spray direction is along the first connecting section 113, which reduces obstruction and allows for a longer spray distance, i.e., a longer pumping head. This ensures that the oil can be pumped into the second connecting section 114, which can quickly fill the second connecting section 114 with oil, thereby cooling the piston body 1.

[0048] Please see Figure 1 and Figure 2In one embodiment, the piston cooling system 100 further includes a main oil passage 100a, a solenoid valve 100b, and an injection oil passage 100c connected in sequence. An oil pump is used to pump oil from the first oil reservoir 22 to the main oil passage 100a. The injection oil passage 100c is connected to the oil inlet passage 51. Specifically, when the engine load exceeds a threshold, the solenoid valve 100b is activated, and the oil pump pumps oil into the main oil passage 100a. The oil then enters the injection oil passage 100c through the solenoid valve 100b. The oil in the injection oil passage 100c flows into the internal cooling oil jacket 11 through the oil inlet passage 51. Assuming it is a four-stroke engine, when the engine load exceeds the threshold, it is determined that the solenoid valve 100b needs to be opened. The solenoid valve 100b is opened when the camshaft phase sensor measures that the piston body 1 is at the bottom dead center position. The oil pump delivers oil to the main oil passage 100a, and then through the solenoid valve 100b into the injection passage 100c. The oil in the injection passage 100c flows into the internal cooling oil jacket 11 through the oil inlet passage 51. At this time, because the piston body 1 is at bottom dead center, the oil inlet 111 of the internal cooling oil jacket 11 aligns perfectly with the oil inlet passage 51 on the cylinder liner 5, allowing oil to enter and fill the internal cooling oil jacket 11, thus cooling the top of the piston body 1. As the piston body 1 continues to move upward from bottom dead center, the internal cooling oil jacket... The oil inlet 111 of the inner cooling oil jacket 11 is misaligned with the oil inlet passage 51 on the cylinder liner 5, preventing engine oil from entering the inner cooling oil jacket 11. At this point, the solenoid valve 100b can be disconnected to avoid wasting engine oil. The engine oil in the inner cooling oil jacket 11 will flow from the outlet 112 to the opening 12, then from the opening 12 to the inlet 31 of the oil collecting component 3, and finally from the outlet 32 ​​of the oil collecting component 3 into the second oil storage area 23 of the oil pan 2. This process collects the high-temperature engine oil and the low-temperature engine oil from other oil-using components of the engine. All oil returns to the first oil storage area 22 through a dedicated return oil channel. In this way, the high-temperature oil undergoes self-cooling in the second oil storage area 23. When the piston body 1 needs to be cooled later, the oil pump will draw low-temperature oil from the first storage area and repeat the above steps to cool the top of the piston body 1. After the high-temperature oil is cooled in the second oil storage area 23, it will enter the first storage area through the connecting hole 211. In this embodiment, the main oil passage 100a and the injection oil passage 100c can be quickly connected or disconnected through the solenoid valve 100b.

[0049] Please see Figure 1In one embodiment, the piston cooling system 100 further includes a first lubrication component 100d and a second lubrication component 100e. One end of both the first lubrication component 100d and the second lubrication component 100e is connected to the main oil passage 100a. The other end of the first lubrication component 100d is connected to the first oil reservoir 22, and the other end of the second lubrication component 100e is connected to the second oil reservoir 23. Specifically, when the engine is running, the engine load determines whether the piston body 1 needs to be cooled. When the engine load exceeds a threshold, the oil pump pumps oil to the oil inlet passage 51. When the piston body 1 moves vertically downward in the cylinder liner 5 and is at the bottom dead center position, the oil inlet 111 of the inner cooling oil jacket 11 of the piston body 1 is connected to the oil inlet passage 51. Oil is sprayed into the inner cooling oil jacket 11 and fills the entire inner cooling oil jacket 11 to cool the top of the piston body 1. The oil in the inner cooling oil jacket 11 absorbs the heat from the top of the piston body 1, and the oil temperature rises. As body 1 continues to move upward from the bottom dead center, the oil inlet 111 of the inner cooling oil jacket 11 is misaligned with the oil inlet passage 51. At this time, the engine oil cannot enter the inner cooling oil jacket 11, and the engine oil in the inner cooling oil jacket 11 will flow out from the oil outlet 112 to the opening 12, and from the opening 12 to the inlet 31 of the oil collecting component 3. Then, it will enter the second oil storage area 23 of the oil pan 2 from the outlet 32 ​​of the oil collecting component 3. In this way, the high-temperature engine oil is collected. The engine oil in the main oil passage 100a will be diverted to the first lubrication component 100d and the second lubrication component 100e. The first lubrication component 100d will lubricate other oil-using parts in the engine. These components generate relatively little heat during operation, resulting in a small temperature rise in the engine oil. The low-temperature oil returns to the first oil reservoir 22 via a dedicated return channel. The oil in the second lubrication assembly 100e flows into the turbocharger. The turbocharger compresses the air entering the engine, increasing intake air density, thereby increasing engine power, improving combustion efficiency, saving fuel, and reducing emissions. This process generates high temperatures, raising the temperature of the oil flowing out of the second lubrication assembly 100e. This high-temperature oil then flows back to the second oil reservoir 23, mixing with the oil flowing out of the piston body 1 opening 12. The oil pump draws low-temperature oil from the first storage area and repeats the above steps when the piston body 1 needs to be cooled. The high-temperature oil, after being cooled in the second oil storage area 23, enters the first storage area through the connecting hole 211. This design separates the low-temperature lubricating oil from the high-temperature oil, preventing them from mixing and causing the oil temperature in the first storage area to become too high. This ensures that the oil in the first storage area can quickly reduce the temperature of the piston body 1 after entering the piston body 1.

[0050] The present invention also provides a crankcase, including a cylinder block, a cylinder head, and the aforementioned piston cooling system 100. The oil pan 2, the cylinder block, and the cylinder head form the inner cavity of the crankcase. The bottom of the piston body 1 is provided with an interconnected cavity with an opening 12, and the cavity is interconnected with the inner cavity. Specifically, as the piston body 1 moves upward at high speed, a negative pressure is generated in the cavity at the bottom of the piston body 1. This negative pressure draws the engine oil in the inner cooling oil jacket 11 into the oil pan 2, thus evacuating and emptying the engine oil in the inner cooling oil jacket 11. Since the crankcase includes all embodiments of the aforementioned piston cooling system 100, it possesses at least all the beneficial effects brought by all the aforementioned embodiments, which will not be elaborated further here.

[0051] The present invention also provides a vehicle including the piston cooling system 100 described above; or the crankcase described above. Since the vehicle includes all embodiments of the piston cooling system 100 or all embodiments of the crankcase described above, it has at least all the beneficial effects of all the above embodiments, which will not be described in detail here.

[0052] In the description of this application, the references to terms such as "some embodiments," "exemplary," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the embodiments of this application. In this application, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine the different embodiments or examples described in this application, as well as the features of the different embodiments or examples.

[0053] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention specification and drawings under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A piston cooling system, characterized in that, The piston cooling system includes: A piston body reciprocates up and down within a cylinder liner. The cylinder liner includes an oil inlet passage. The piston body includes an internal cooling oil sleeve and an opening. The internal cooling oil sleeve includes an oil inlet and an oil outlet. The oil inlet is used to communicate with the oil inlet passage, and the oil outlet is used to communicate with the opening. An oil pan, wherein a partition plate is provided in the oil pan to divide the inner cavity of the oil pan into a first oil storage area and a second oil storage area, and the partition plate is formed with a connecting hole; An oil pump, the oil pump being used to pump oil from the first oil reservoir to the oil inlet passage; An oil collecting component includes an inlet and an outlet that are interconnected, the inlet being located at the bottom of the opening and the outlet being located at the top of the second oil storage area.

2. The piston cooling system as described in claim 1, characterized in that, The outer surface of the oil pan is provided with a plurality of heat dissipation fins, which are located on the side close to the second oil storage area.

3. The piston cooling system as described in claim 1, characterized in that, The second oil storage area is designed to be located on the windward side of the vehicle.

4. The piston cooling system as described in claim 1, characterized in that, The diameter of the oil inlet channel is larger than the diameter of the oil inlet port.

5. The piston cooling system as described in claim 1, characterized in that, The number of oil inlet passages is multiple, and the multiple oil inlet passages are arranged at intervals along the vertical direction on the cylinder liner.

6. The piston cooling system as described in claim 1, characterized in that, A gap is formed between the outer side of the piston body and the cylinder liner, and the gap is filled with engine oil to form an oil film.

7. The piston cooling system as described in any one of claims 1 to 6, characterized in that, The outer surface of the top of the piston body is provided with a first annular groove. The piston cooling system also includes a first piston ring, which is engaged in the first annular groove and extends out of the piston body. The first piston ring contacts the inner wall of the cylinder liner.

8. The piston cooling system as described in claim 7, characterized in that, The outer surface of the top of the piston body is also provided with a second annular groove, which is located at the bottom of the first annular groove. The piston cooling system also includes a second piston ring, which is engaged in the second annular groove and extends out of the piston body. The second piston ring contacts the inner wall of the cylinder liner.

9. The piston cooling system as described in any one of claims 1 to 6, characterized in that, The oil inlet passage is inclined toward the piston body. The internal cooling oil jacket includes a first connecting section, a second connecting section, and a third connecting section connected in sequence. The first connecting section is inclined, the second connecting section is horizontal, the first connecting section is connected to the oil inlet passage, and the third connecting section is connected to the opening.

10. The piston cooling system as described in any one of claims 1 to 6, characterized in that, The piston cooling system further includes a main oil passage, a solenoid valve, and an injection oil passage connected in sequence. The oil pump is used to pump the oil in the first oil storage area to the main oil passage, and the injection oil passage is connected to the oil inlet passage.

11. The piston cooling system as claimed in claim 10, characterized in that, The piston cooling system further includes a first lubrication component and a second lubrication component. One end of the first lubrication component and the second lubrication component are both connected to the main oil passage. The other end of the first lubrication component is connected to the first oil storage area, and the other end of the second lubrication component is connected to the second oil storage area.

12. A crankcase, characterized in that, The system includes a cylinder block, a cylinder head, and a piston cooling system according to any one of claims 1 to 11, wherein the oil pan, the cylinder block, and the cylinder head form the inner cavity of the crankcase, and the bottom of the piston block is provided with a cavity that communicates with the opening, the cavity being in communication with the inner cavity.

13. A vehicle, characterized in that, The piston cooling system includes any one of claims 1 to 11; or the crankcase according to claim 12.

Images