Engine lubrication structure and engine

Abstract

The utility model provides a kind of engine lubrication structure, including the lubricating oil channel being set on crankcase and the cylinder block being set on crankcase, reciprocating slideable piston being set in cylinder block, first oil injection hole for spraying lubricating oil towards piston bottom is provided on the crankcase, the first oil injection hole is communicated with lubricating oil channel, it is characterized by: second oil injection hole is further provided on the lubricating oil channel, the second oil injection hole injection direction is different from first oil injection hole, the second oil injection hole can intermittently spray lubricating oil on the bottom and sidewall of cylinder wall and piston.The utility model can not only achieve cooling and lubrication of piston intake and exhaust side, but also can cool and lubricate cylinder wall, and optimizes lubrication structure, so that layout is compact, special parts are reduced, reduces the manufacturing cost and material cost of whole machine, improves workmanship, reduces assembly step, and the structure can ensure normal operation of engine and improve engine service life.

Description

Technical Field

[0001] This utility model relates to the field of engine lubrication technology, and more particularly to an engine lubrication structure and an engine. Background Technology

[0002] The lubrication system is one of the five essential systems for the normal operation of an engine, and piston back-cooling technology within the lubrication system is becoming increasingly widely used. Currently, there are two main methods for piston back-cooling lubrication: one is to cool only the intake or exhaust side of the piston, and the other is to cool both the intake and exhaust sides simultaneously. However, with the development trend of the engine industry, the requirements for engine environmental friendliness and resource renewability are becoming increasingly stringent. Therefore, many countries are now promoting the use of ethanol gasoline. However, during the combustion process of ethanol gasoline (especially during cold engine starts), due to incomplete combustion, the residual ethanol gasoline will damage the lubricating oil film on the cylinder walls more quickly than traditional fuels, greatly increasing abnormal engine wear and even cylinder scoring.

[0003] However, the current engine cooling and lubrication arrangement has the following drawbacks:

[0004] The first type of piston back-cooling uses an injection point structure on the housing or a separately extended nozzle for oil spray cooling. This type of piston has a single cooling lubrication point, which is not optimal. The second type of piston back-cooling has the same structure as the first, but requires two separate lubrication lines and two injection points or nozzles. This piston cooling lubrication method is more effective than the first, but the lubrication lines in the housing are not only more complex, but also require a larger oil pump, and using two nozzles increases engine costs.

[0005] For engines using ethanol gasoline, the combustion of ethanol gasoline is incomplete during combustion (especially when the engine is cold-started). The residual ethanol gasoline will damage the lubricating oil film on the cylinder wall faster than conventional fuel, greatly increasing abnormal wear of the engine and even causing cylinder scoring.

[0006] Currently, engine piston lubrication and cooling structures only target the intake and exhaust sides of the piston with point-to-point injection, and there is no structure that can simultaneously lubricate and cool the piston and cylinder walls. Utility Model Content

[0007] The purpose of this invention is to provide an engine lubrication structure that can cool and lubricate the intake and exhaust sides of the piston, as well as the cylinder wall, while also having the advantage of simple structure.

[0008] This invention provides an engine lubrication structure, including a lubrication oil passage on a crankcase and a cylinder block mounted on the crankcase, and a reciprocating piston mounted within the cylinder block. A first oil spray hole, communicating with the lubrication oil passage, is provided on the crankcase to spray lubricating oil towards the bottom of the piston. A second oil spray hole is also provided on the lubrication oil passage, with a different spray direction than the first oil spray hole. The second oil spray hole intermittently sprays lubricating oil onto the cylinder wall, the bottom of the piston, and the inner side wall of the piston. This structure not only cools the bottom and sides of the piston but also lubricates the sliding surfaces between the piston and the cylinder block, preventing abnormal wear caused by damage to the lubricating oil film on the cylinder wall due to combustion.

[0009] Furthermore, the first and second injection holes are formed on the same lubrication channel and located on the same injection pipe, forming a specific angle. This structure simplifies the setting of the injection holes, setting two injection holes on the same injection pipe, reducing the trouble and design difficulty of adding injection pipes, and also saving costs.

[0010] Furthermore, the oil injection pipe is fixed to the lubrication oil passage of the crankcase by thread or interference fit. This structure is simple to install and quick and easy to manufacture.

[0011] Furthermore, the second injection hole is located at the front end of the first injection hole. This structure allows for better positioning of the second injection hole and better control over the injection direction.

[0012] Furthermore, the fuel injection pipe is a circular tube with an upward bend at the end to form the first fuel injection hole. This structure is simple and convenient to manufacture.

[0013] Furthermore, the second injection hole is formed by opening a small-diameter hole in the side wall of the injection pipe and is located at the front end of the first injection hole. This structure is convenient and simple to manufacture and easy to operate.

[0014] Furthermore, the fuel injection pipe is fixed to a mounting plate, and screw holes are provided on one side of the mounting plate. The fuel injection pipe is then fixed to the crankcase using screws, thus connecting and securing the fuel injection pipe to the lubricating oil passage. This structure provides a better operational method for connecting the fuel injection pipe and allows for a more rational installation approach.

[0015] Furthermore, the second injection hole can spray oil onto the cylinder wall at the lowest point of the piston skirt when the piston is at its highest point. This point is where the piston and cylinder wall experience the greatest stress, making it more prone to abnormal wear. Therefore, spraying lubricating oil onto this point better ensures lubrication and prevents abnormal wear or even cylinder scoring.

[0016] This invention also provides an engine equipped with the aforementioned engine lubrication structure. An engine with this structure can ensure normal engine operation and extend its service life.

[0017] Beneficial effects:

[0018] The engine lubrication structure of this utility model can achieve cooling and lubrication of the piston intake and exhaust sides, as well as cooling and lubrication of the cylinder wall. Furthermore, the optimized lubrication structure results in a compact layout, fewer specialized parts, reduced overall manufacturing and material costs, improved manufacturability, and fewer assembly steps. At the same time, this structure can ensure the normal operation of the engine and extend its service life. Attached Figure Description

[0019] Figure 1 This is a schematic diagram showing the piston located at the lowest point of the cylinder block.

[0020] Figure 2 This is a schematic diagram of a piston located in the middle of the cylinder block.

[0021] Figure 3 This is a schematic diagram showing the piston located at the highest point of the cylinder block.

[0022] Figure 4 A schematic diagram of a structure with injection holes on an injection pipe. Detailed Implementation

[0023] This utility model provides an engine lubrication structure, such as Figure 1-4As shown, the system includes a crankcase 1 and suspension holes 7 and 8 on the crankcase. Lubricating oil passages are also provided on the crankcase, as well as a cylinder block 2 mounted on the crankcase. A crankshaft 6 is rotatably mounted on the crankcase 1, and a connecting rod 5 connected to the crankshaft is connected to the other end of the connecting rod 5. The piston 3 can reciprocate within the cylinder block 2. A first oil injection hole 41 is provided on the crankcase 1 to spray lubricating oil towards the bottom of the piston 3. The spray direction of the first oil injection hole is substantially parallel to the cylinder block axis, allowing the lubricating oil to be continuously sprayed onto the piston. The bottom of the cylinder is sealed; the first oil injection hole 1 communicates with the lubricating oil passage, and a second oil injection hole 42 is also provided on the lubricating oil passage. The spray direction of the second oil injection hole 42 is different from that of the first oil injection hole. The second oil injection hole can intermittently spray lubricating oil onto the cylinder wall, the bottom of the piston, and the inner side wall of the piston. The second oil injection hole is oblique to the cylinder wall and deviates from the side opposite to the first oil injection hole. Since the piston runs on the cylinder wall, most of the lubricating oil sprayed by the second oil injection hole is sprayed onto the bottom of the piston or the side wall of the piston. Only when the piston runs to the top can the lubricating oil be sprayed onto the cylinder wall. This structure not only simplifies the oil circuit of the housing lubrication and improves the processability, but also reduces assembly steps and lowers costs. Meanwhile, the newly added cylinder wall intermittently lubricates the engine cylinder wall at the point of maximum thrust contact between the piston skirt and the cylinder wall when the crankshaft rotates to a specific angle (i.e., when the crankshaft angle is 15° to 17°). In particular, the continuous injection of oil protects the oil film on the engine cylinder wall from the damage caused by ethanol gasoline, lubricates the contact surface between the piston skirt and the cylinder wall, reduces friction loss between the piston and the cylinder wall at the point of maximum thrust, and extends service life. At the same time, this structure can cool the bottom and sides of the piston and lubricate the sliding surface between the piston and the cylinder block, avoiding abnormal wear caused by damage to the lubricating oil film on the cylinder wall due to combustion problems.

[0024] The dotted line in the diagram is a schematic diagram of the spraying of lubricating oil.

[0025] In this embodiment: as Figure 4 The first and second injection holes 41 and 42 are formed on the same lubrication channel and located on the same injection pipe 4, forming a specific angle. This specific angle is because the angle is unique; only within this specific angle can the second injection hole spray lubricating oil onto the cylinder wall. This structure simplifies the injection hole arrangement, providing two injection holes on the same injection pipe, reducing the hassle and design difficulty of adding injection pipes, reducing assembly steps, and saving manufacturing costs.

[0026] In this embodiment: as Figure 4 As shown, the oil injection pipe 4 is fixed to the lubrication oil passage of the crankcase 1 by thread or interference fit. This structure is simple to install and quick to manufacture.

[0027] In this embodiment: as follows Figure 4 As shown, the second injection hole 42 is located at the front end of the first injection hole. This structure allows for better positioning of the second injection hole and better control over the injection direction.

[0028] In this embodiment: as follows Figure 4 As shown, the fuel injection pipe 4 is a circular pipe that bends upward at one end to form a first fuel injection hole 41, and the inner diameter gradually decreases from the bend until the injection hole reaches the required injection diameter. This structure is simple and convenient to manufacture.

[0029] In this embodiment: as follows Figure 4 As shown, the second injection hole 2 is formed by opening a small-diameter hole in the side wall of the injection pipe and is located at the front end of the first injection hole. This structure is convenient and simple to manufacture and easy to operate. Note: Here, "front end" refers to the order in which the lubricating oil arrives; the point that arrives first is considered "front," and the point that arrives later is considered "back."

[0030] In this embodiment: as follows Figure 3 , 4 As shown, the fuel injection pipe 4 is fixed to a mounting plate 9. Screw holes 10 are provided on one side of the mounting plate 9. The fuel injection pipe is fixed to the crankcase using screws, thus connecting and securing the fuel injection pipe to the lubricating oil passage. A sealing device is also provided at the connection point between the fuel injection pipe and the lubricating oil passage. This structure provides a better operating method for connecting the fuel injection pipe and allows for a more reasonable installation method.

[0031] In this embodiment: as follows Figure 3 , 4 As shown, the second injection hole 42 can spray oil onto the cylinder wall at the lowest point of the piston skirt when the piston is at its highest point. Since the injection hole sprays lubricating oil during both the piston's upward and downward movements, the oil is only sprayed onto the cylinder wall at the point where the piston is at its highest point, i.e., the lower end of the piston skirt. This point is where the maximum force between the piston and the cylinder wall occurs, making it more prone to abnormal wear. Therefore, spraying lubricating oil at this point better ensures lubrication and prevents abnormal wear or even cylinder scoring.

[0032] This invention also provides an engine equipped with the aforementioned engine lubrication structure. An engine with this structure can ensure normal engine operation and extend its service life.

[0033] Working principle

[0034] Only one lubrication oil passage is designed on the engine crankcase. Lubricating oil, pressurized by the oil pump, flows through this passage directly to the oil nozzle. The oil nozzle has two injection holes 41 and 42, forming a specific angle. Figure 4As shown. Lubricating oil is sprayed through the two injection holes to lubricate and cool the piston's back (intake and exhaust sides) at specific points. Throughout the engine's operation, the lubricating oil passing through injection hole 41 on the oil nozzle continuously lubricates and cools the exhaust side of the piston's back. Meanwhile, injection hole 42 of the oil nozzle lubricates and cools the intake side of the piston's back when the piston reaches the lower part of the cylinder block. Figure 1 , 2 As shown in the figure. In addition, when the piston reaches the top of the cylinder block, Figure 3 As shown, lubricating oil is sprayed onto the cylinder wall through the injection hole 42 on the oil nozzle. This injection point is where the cylinder block and piston skirt experience the greatest contact thrust during engine operation (i.e., at the engine's maximum burst pressure). This effectively increases the oil film replenishment during the frictional movement of the cylinder block and piston (especially for engines using ethanol fuel), achieving lubrication and cooling. The lubrication structure arrangement of this patent can simultaneously lubricate and cool both the intake and exhaust sides of the piston back, and also achieve intermittent, targeted injection lubrication at the point of maximum thrust in the cylinder block, achieving three benefits in one. Structurally, it is compact; in terms of manufacturing, it simplifies the oil circuit; in terms of assembly, it reduces the number of steps; in terms of specialized parts, it reduces the number of components; and in terms of overall material costs, it lowers the overall cost.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the spirit and scope of the technical solutions of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. An engine lubrication structure, comprising a lubricating oil passage provided on a crankcase and a cylinder block provided on the crankcase, a reciprocating piston disposed within the cylinder block, and a first oil injection hole provided on the crankcase for spraying lubricating oil toward the bottom of the piston, the first oil injection hole communicating with the lubricating oil passage, characterized in that: A second oil injection hole is also provided on the lubricating oil passage. The second oil injection hole sprays oil in a different direction than the first oil injection hole. The second oil injection hole can intermittently spray lubricating oil onto the cylinder wall, the bottom of the piston, and the inner side wall of the piston.

2. The engine lubrication structure according to claim 1, characterized in that: The first and second oil injection holes are formed in the same lubrication oil passage and located on the same oil injection pipe, forming a specific angle.

3. The engine lubrication structure according to claim 2, characterized in that: The oil injection pipe is fixed to the lubrication oil passage of the crankcase by threads or interference fit.

4. The engine lubrication structure according to claim 3, characterized in that: The second injection hole is located at the front end of the first injection hole.

5. The engine lubrication structure according to claim 4, characterized in that: The fuel injection pipe is a round pipe with a first fuel injection hole formed by bending upward at the end.

6. The engine lubrication structure according to claim 5, characterized in that: The second injection hole is formed by opening a small-diameter hole on the side wall of the injection pipe and is located at the front end of the first injection hole.

7. The engine lubrication structure according to claim 3, characterized in that: The oil injection pipe (4) is fixed on a mounting plate. A screw hole is provided on one side of the mounting plate. The oil injection pipe is fixed on the crankcase by screws, so that the oil injection pipe is connected and fixed to the lubricating oil passage.

8. The engine lubrication structure according to claim 5, characterized in that: The second injection hole can spray oil onto the cylinder wall at the lowest point of the piston skirt when the piston is at its highest point.

9. An engine, characterized in that: The engine is equipped with an engine lubrication structure as described in any one of claims 1-8.

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