Thrust structure, design method thereof and engine

Abstract

The application discloses a thrust structure, a design method thereof and an engine, and belongs to the technical field of bearings. The thrust structure comprises a cover assembly, a thrust shaft assembly and a thrust bearing assembly. The cover assembly comprises a cover body and an end cover which are connected. The thrust shaft assembly is located in a containing cavity. The thrust shaft assembly comprises a thrust shaft body. The thrust shaft body is configured to connect a side of the thrust shaft body away from the end cover with a crankshaft of the engine. The thrust bearing assembly comprises a first thrust bearing and a second thrust bearing. The first thrust bearing is connected with the end cover. At least part of the thrust shaft body is located between the first thrust bearing and the second thrust bearing and is connected with the first thrust bearing and the second thrust bearing respectively. The thrust structure is external. When the thrust bearing assembly needs to be disassembled, the first thrust bearing can be taken out by sequentially taking down the end cover. Further, the second thrust bearing can be taken out by taking down the thrust shaft body. The time required for disassembly is short, and special disassembly tools are not needed, so that the disassembly is convenient and fast.

Description

Technical Field

[0001] This application belongs to the field of bearing technology, specifically relating to a thrust structure, its design method, and an engine. Background Technology

[0002] Thrust bearings are crucial positioning components in marine engines, limiting the axial movement of the crankshaft. They primarily bear the constant or instantaneous axial forces generated by the crankshaft. If the engine's thrust bearing experiences excessive load, leading to localized overheating of the oil film and subsequent dry friction and abnormal wear, excessive crankshaft movement will result. In severe cases, this can cause serious engine malfunctions, piston seizure, and other major failures. Common thrust bearing structures are split or flat, also known as thrust bearings. These types of thrust bearings generally have relatively low load-bearing capacity, with permissible axial forces typically below 10kN, making them unsuitable for the demands of high-performance marine engines operating in various complex and harsh sea conditions. Furthermore, thrust bearings are usually located inside the engine. Abnormal wear typically requires disassembly of the high-elasticity coupling, flywheel, oil seal, and main bearings at the output end, resulting in time-consuming disassembly and maintenance with numerous specialized tools. Summary of the Invention

[0003] Purpose of the invention: The embodiments of this application provide a thrust structure, its design method, and an engine, aiming to solve the technical problems of low load-bearing capacity and long disassembly and maintenance time of thrust bearings.

[0004] Technical solution: This application provides a thrust-damping structure connected to an engine, comprising:

[0005] A cover assembly includes a cover body and an end cap connected together, the cover body having an opening, the end cap sealing the opening and enclosing the cover body to form a receiving cavity.

[0006] A thrust shaft assembly, located within a receiving cavity, includes a thrust shaft body configured to connect the side of the thrust shaft body away from the end cap to the crankshaft of an engine;

[0007] A thrust bearing assembly includes a first thrust bearing and a second thrust bearing, the first thrust bearing being connected to an end cap, and at least a portion of the thrust shaft body being located between and connected to the first and second thrust bearings respectively.

[0008] In some embodiments, the thrust shaft assembly includes an oil supply plug connected to the crankshaft, the oil supply plug having an inlet;

[0009] The thrust shaft body has an oil hole and a receiving space that connects to the oil hole, and the inlet is connected to the receiving space.

[0010] In some embodiments, the thrust shaft assembly includes a pressure plate disposed on the side of the thrust shaft body away from the end cap and connected to the thrust shaft body. The pressure plate has an outlet that communicates with both the inlet and the receiving space.

[0011] In some embodiments, the oil hole includes a first sub-oil hole and a second sub-oil hole;

[0012] The end cap, the first thrust bearing, and the thrust shaft body together form a first chamber, and the first sub-oil hole communicates with the first chamber.

[0013] The end cap, the second thrust bearing, and the cover body together form a second chamber, and the second sub-oil hole communicates with the second chamber.

[0014] In some embodiments, a first outlet is provided between the thrust shaft body and the cover body, and the first outlet communicates with a second chamber.

[0015] The cover body has a second outlet, which is connected to a second chamber.

[0016] In some embodiments, the end cap has a third outlet that communicates with the first chamber.

[0017] In some embodiments, the thrust shaft assembly includes a partition located within a receiving space and connected to the thrust shaft body.

[0018] In some embodiments, the cover assembly includes a gasket disposed between the cover body and the end cap, and connected to the cover body and the end cap respectively.

[0019] In some embodiments, the first thrust bearing and the second thrust bearing comprise an annular thrust bearing; or

[0020] The first thrust bearing and the second thrust bearing include tilting pad thrust bearings.

[0021] Accordingly, this application provides an engine including the aforementioned thrust structure.

[0022] Accordingly, embodiments of this application provide a design method for a thrust-stop structure, comprising the following steps:

[0023] Determine the dimensions of the thrust bearing assembly;

[0024] Perform load-bearing capacity verification calculations on the thrust bearing assembly;

[0025] Determine the dimensions of the thrust shaft body in the thrust shaft assembly and the dimensions of the oil holes on the thrust shaft body;

[0026] The shaft torsional vibration of the thrust shaft assembly and the lubrication system were calculated and simulated.

[0027] Beneficial Effects: The thrust structure of this application embodiment, connected to an engine, includes a cover assembly, a thrust shaft assembly, and a thrust bearing assembly. The cover assembly includes a cover body and an end cap connected together. The cover body has an opening, and the end cap seals the opening and surrounds the cover body to form a receiving cavity. The thrust shaft assembly is located within the receiving cavity and includes a thrust shaft body configured to connect the side of the thrust shaft body away from the end cap to the crankshaft of the engine. The thrust bearing assembly includes a first thrust bearing and a second thrust bearing. The first thrust bearing is connected to the end cap, and at least a portion of the thrust shaft body is located between and connected to the first and second thrust bearings, respectively. The thrust structure of this application embodiment is external. When the thrust bearing assembly needs to be disassembled, the first thrust bearing can be removed by simply removing the end cap, and further, the second thrust bearing can be removed by removing the thrust shaft body. The disassembly and assembly time is short, and no complicated special disassembly and assembly tools are required, making it convenient and quick.

[0028] The engine in this application embodiment includes the thrust-damping structure described above. Therefore, the engine can have all the technical features and beneficial effects of the thrust-damping structure described above, which will not be repeated here.

[0029] The design method of the thrust bearing structure in this application includes the following steps: determining the dimensions of the thrust bearing assembly; performing load-bearing capacity verification calculations on the thrust bearing assembly; determining the dimensions of the thrust shaft body and the oil hole dimensions on the thrust shaft body in the thrust shaft assembly; and performing shaft torsional vibration calculations and lubrication system simulation analysis on the thrust shaft assembly. The thrust bearing assembly is used to withstand axial loads generated inside and outside the engine. By rationally designing the dimensions of the thrust bearing assembly and performing load-bearing capacity verification calculations, it can be ensured that the thrust bearing assembly can work stably and reliably during engine operation, whether under constant or instantaneous axial force. This prevents failures such as oil film rupture, dry friction, and abnormal wear due to insufficient load-bearing capacity, ensuring normal engine operation and extending the service life of the thrust bearing assembly. The thrust shaft assembly is used to transmit engine speed and axial load, and is responsible for providing lubricating oil from the crankshaft to the thrust bearing assembly. By rationally designing the dimensions of the thrust shaft body and the oil hole dimensions on the thrust shaft body, on the one hand, shaft system torsional vibration calculations can ensure the precise fit between the thrust shaft body, the thrust bearing assembly, and the crankshaft, ensuring that the strength and stiffness of the thrust shaft body meet the requirements, ensuring that the thrust shaft body adapts to the engine's torsional vibration environment, avoiding deformation or damage during operation, reducing fatigue damage to the thrust shaft body, and ensuring the smoothness and reliability of engine operation. On the other hand, simulation analysis of the lubrication system can optimize the oil circuit design of the lubrication system, determine the appropriate lubrication flow and pressure, improve the load-bearing capacity and service life of the thrust bearing assembly, and at the same time reduce power loss and improve the overall efficiency of the engine. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a cross-sectional view of a thrust structure according to an embodiment of this application;

[0032] Figure 2 This is a schematic diagram of a thrust-stopping structure according to an embodiment of this application;

[0033] Figure 3 This is a cross-sectional view of a cover assembly according to an embodiment of this application;

[0034] Figure 4 yes Figure 3 Enlarged view of part A;

[0035] Figure 5 This is a cross-sectional view of a thrust shaft assembly according to an embodiment of this application;

[0036] Figure 6 This is a cross-sectional view of a thrust shaft body according to an embodiment of this application;

[0037] Figure 7 This is a flowchart illustrating a design method for a thrust-stop structure according to an embodiment of this application.

[0038] Reference numerals: 1. Cover assembly; 2. Thrust shaft assembly; 3. Thrust bearing assembly; 4. First chamber; 5. Second chamber; 6. First outlet; 10. Cover body; 11. End cap; 12. Opening; 13. Receiving cavity; 14. Second outlet; 15. Third outlet; 16. Gasket; 20. Thrust shaft body; 21. Oil supply plug; 22. Pressure plate; 23. Partition plate; 30. First thrust bearing; 31. Second thrust bearing; 100. Crankshaft; 101. Vibration damper; 102. Machine body; 200. Oil hole; 201. Receiving space; 210. Inlet; 220. Outlet; 2000. First sub-oil hole; 2001. Second sub-oil hole. Detailed Implementation

[0039] The technical solutions of the embodiments of this application 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 this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0040] In the description of this application, it should be understood that the terms "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, and "at least one" can mean one, two, or more, unless otherwise explicitly specified. In the description of this application, "perpendicular" means completely perpendicular to 90° or almost completely perpendicular, for example, the range of included angles from 80° to 100° is considered perpendicular. Similarly, "parallel" means completely parallel or almost completely parallel, for example, the range of completely parallel angles from 10° is considered parallel.

[0041] The applicant noted that thrust bearings are crucial positioning components in marine engines, limiting the axial movement of the crankshaft and primarily bearing the constant or instantaneous axial force generated by the crankshaft. If the engine's thrust bearing experiences excessive load, leading to localized overheating of the oil film and subsequent dry friction and abnormal wear, it will result in excessive crankshaft movement, potentially causing serious engine malfunctions, piston seizure, and other major failures. Common thrust bearing structures are split or flat, also known as thrust bearings. These types of thrust bearings generally have relatively low load-bearing capacity, with permissible axial force typically below 10kN, making them unsuitable for the demands of high-performance marine engines operating in various complex and harsh sea conditions. Furthermore, thrust bearings are usually located inside the engine. Abnormal wear typically requires disassembly of the high-elasticity coupling, flywheel, oil seal, and main bearing at the output end, resulting in time-consuming disassembly and maintenance with numerous specialized tools.

[0042] In view of this, embodiments of this application provide a thrust structure connected to an engine, including a cover assembly, a thrust shaft assembly, and a thrust bearing assembly. The cover assembly includes a cover body and an end cap connected together. The cover body has an opening, and the end cap seals the opening and forms a receiving cavity with the cover body. The thrust shaft assembly is located within the receiving cavity and includes a thrust shaft body configured to connect the side of the thrust shaft body away from the end cap to the crankshaft of the engine. The thrust bearing assembly includes a first thrust bearing and a second thrust bearing. The first thrust bearing is connected to the end cap, and at least a portion of the thrust shaft body is located between and connected to the first and second thrust bearings, respectively. The thrust structure of this application is externally mounted. When the thrust bearing assembly needs to be disassembled, the first thrust bearing can be removed by sequentially removing the end cap, and further, the second thrust bearing can be removed by removing the thrust shaft body. The disassembly and assembly are quick and easy, requiring no complex or specialized tools. This application also provides a design method for a thrust bearing structure, including the following steps: determining the dimensions of the thrust bearing assembly; performing load-bearing capacity verification calculations on the thrust bearing assembly; determining the dimensions of the thrust shaft body and the oil hole dimensions on the thrust shaft body in the thrust shaft assembly; and performing shaft torsional vibration calculations and lubrication system simulation analysis on the thrust shaft assembly. The thrust bearing assembly is used to withstand axial loads generated inside and outside the engine. By rationally designing the dimensions of the thrust bearing assembly and performing load-bearing capacity verification calculations, it can be ensured that the thrust bearing assembly can work stably and reliably during engine operation, whether under constant or instantaneous axial force. This prevents failures such as oil film rupture, dry friction, and abnormal wear due to insufficient load-bearing capacity, ensuring normal engine operation and extending the service life of the thrust bearing assembly. The thrust shaft assembly is used to transmit engine speed and axial load, and is responsible for providing lubricating oil from the crankshaft to the thrust bearing assembly. By rationally designing the dimensions of the thrust shaft body and the oil hole dimensions on the thrust shaft body, on the one hand, shaft system torsional vibration calculations can ensure the precise fit between the thrust shaft body, the thrust bearing assembly, and the crankshaft, ensuring that the strength and stiffness of the thrust shaft body meet the requirements, ensuring that the thrust shaft body adapts to the engine's torsional vibration environment, avoiding deformation or damage during operation, reducing fatigue damage to the thrust shaft body, and ensuring the smoothness and reliability of engine operation. On the other hand, simulation analysis of the lubrication system can optimize the oil circuit design of the lubrication system, determine the appropriate lubrication flow and pressure, improve the load-bearing capacity and service life of the thrust bearing assembly, and at the same time reduce power loss and improve the overall efficiency of the engine.

[0043] The thrust-damping structure, its design method, and the engine of this application will be described in detail below with reference to the accompanying drawings. Unless otherwise specified, the features of the following embodiments and implementations can be combined with each other.

[0044] Figure 1 This is a cross-sectional view of a thrust structure according to an embodiment of this application; Figure 2 This is a schematic diagram of a thrust-stopping structure according to an embodiment of this application; Figure 3 This is a cross-sectional view of a cover assembly according to an embodiment of this application; Figure 4 yes Figure 3 Enlarged view of part A; Figure 5 This is a cross-sectional view of a thrust shaft assembly according to an embodiment of this application; Figure 6 This is a cross-sectional view of a thrust shaft body according to an embodiment of this application.

[0045] refer to Figures 1 to 6 This application provides a thrust-resistant structure connected to an engine, including a cover assembly 1, a thrust shaft assembly 2, and a thrust bearing assembly 3. The cover assembly 1 includes a cover body 10 and an end cap 11 connected to each other. The cover body 10 has an opening 12, and the end cap 11 covers the opening 12 and surrounds the cover body 10 to form a receiving cavity 13. The cover body 10 provides support for the thrust bearing assembly 3 and forms the receiving cavity 13 for providing lubrication to the thrust bearing. The engine crankshaft 100 and a vibration damper are disposed in the receiving cavity 13. The vibration damper works in conjunction with the crankshaft 100 to reduce the impact of crankshaft 100 vibration on the thrust-resistant structure, protecting the thrust-resistant structure from excessive vibration damage.

[0046] The thrust shaft assembly 2 is located within the receiving cavity 13. The thrust shaft assembly 2 includes a thrust shaft body 20, which is configured to connect the side of the thrust shaft body 20 away from the end cap 11 to the crankshaft 100 of the engine. The thrust shaft assembly 2 is used to transmit engine speed and axial load and is responsible for providing lubricating oil from the crankshaft 100 to the thrust bearing assembly 3 for lubrication of the thrust bearing.

[0047] The thrust bearing assembly 3 includes a first thrust bearing 30 and a second thrust bearing 31. The first thrust bearing 30 is connected to the end cover 11. At least a portion of the thrust shaft body 20 is located between the first thrust bearing 30 and the second thrust bearing 31 and is connected to both the first thrust bearing 30 and the second thrust bearing 31. The thrust bearing assembly 3 is used to withstand axial loads generated inside and outside the engine.

[0048] refer to Figure 2 In this embodiment, the thrust structure is external, that is, the thrust structure is set on one side of the engine block 102. When it is necessary to disassemble the thrust bearing assembly 3, the first thrust bearing 30 can be taken out by simply removing the end cover 11 in sequence. Furthermore, the second thrust bearing 31 can be taken out by removing the thrust shaft body 20. The disassembly and assembly are quick and easy, without the need for complicated special disassembly and assembly tools.

[0049] In some embodiments, the thrust bearing assembly 3 may be lubricated by immersion lubrication. Immersion lubrication has a simple structure and is typically used in low-speed rotating machinery. In other embodiments, the thrust bearing assembly 3 may be lubricated by direct oil injection. Direct oil injection lubrication is suitable for high-speed, heavy-load conditions. This lubrication method can effectively increase the load-bearing capacity of the thrust bearing assembly 3, reduce power loss, and lower bearing temperature. It is generally selected when the linear velocity of the thrust bearing is above 50 m / s. This application does not impose any limitations on this.

[0050] exist Figures 1 to 5 In the illustrated embodiment, the thrust bearing assembly 3 is lubricated by immersion lubrication. The thrust shaft assembly 2 includes an oil supply plug 21 connected to the crankshaft 100, and the oil supply plug 21 has an inlet 210. The thrust shaft body 20 has an oil hole 200 and a receiving space 201 communicating with the oil hole 200, with the inlet 210 communicating with the receiving space 201. Lubricating oil enters the receiving space 201 of the thrust shaft body 20 through the inlet 210 of the oil supply plug 21 and flows out through the oil hole 200 to lubricate the thrust bearing assembly 3. This configuration can reduce local wear of the thrust bearing assembly 3, extend the service life of the thrust bearing assembly 3, and improve the reliability and stability of the thrust structure.

[0051] exist Figure 1 and Figure 5 In the illustrated embodiment, the thrust shaft assembly 2 includes a pressure plate 22, which is disposed on the side of the thrust shaft body 20 away from the end cap 11 and connected to the thrust shaft body 20. The pressure plate 22 has an outlet 220, which communicates with both the inlet 210 and the receiving space 201. The pressure plate 22 is sandwiched between the crankshaft 100 and the thrust shaft body 20 and connected to the vibration damper for fixation. Exemplarily, the pressure plate 22 is fixed to the vibration damper by bolts. Lubricating oil enters the receiving space 201 of the thrust shaft body 20 through the inlet 210 of the oil supply plug 21 and the outlet 220 of the pressure plate 22, and flows out through the oil hole 200 to lubricate the thrust bearing assembly 3. This arrangement can reduce local wear of the thrust bearing assembly 3, extend the service life of the thrust bearing assembly 3, and improve the reliability and stability of the thrust structure.

[0052] exist Figure 1 , Figure 5 and Figure 6In the illustrated embodiment, the oil hole 200 includes a first sub-oil hole 2000 and a second sub-oil hole 2001; the end cap 11, the first thrust bearing 30, and the thrust shaft body 20 enclose a first chamber 4, and the first sub-oil hole 2000 communicates with the first chamber 4; the end cap 11, the second thrust bearing 31, and the cover body 10 enclose a second chamber 5, and the second sub-oil hole 2001 communicates with the second chamber 5. With this configuration, a portion of the lubricating oil enters the receiving space 201 of the thrust shaft body 20 through the inlet 210 of the oil supply plug 21 and the outlet 220 of the pressure plate 22, and flows out through the first sub-oil hole 2000 to enter the first chamber 4, thereby lubricating the first thrust bearing 30. Another portion of the lubricating oil enters the receiving space 201 of the thrust shaft body 20 through the inlet 210 of the oil supply plug 21 and the outlet 220 of the pressure plate 22, and flows out through the second sub-oil hole 2001 to enter the second chamber 5, thereby lubricating the second thrust bearing 31. Delivering lubricating oil to the first chamber 4 and the second chamber 5, where the first thrust bearing 30 and the second thrust bearing 31 are located, respectively, can improve lubrication efficiency, reduce power loss, and lower the temperature of the thrust bearing assembly 3.

[0053] exist Figure 1 In the illustrated embodiment, a first outlet 6 is provided between the thrust shaft body 20 and the cover body 10, and the first outlet 6 communicates with the first chamber 4. When the lubricating oil fills the first chamber 4, it can return through the first outlet 6. The cover body 10 has a second outlet 14, which communicates with the second chamber 5. When the first outlet 6 cannot return oil in time, the lubricating oil can leak out through the second outlet 14.

[0054] exist Figure 1 and Figure 3 In the illustrated embodiment, the end cap 11 has a third outlet 15, which communicates with the first chamber 4. The third outlet 15 is sealed by a screw plug. When disassembling the end cap 11, the screw plug is first removed to allow residual lubricating oil in the first chamber 4 and the second chamber 5 to drain through the third outlet 15. Then, the end cap 11, the first thrust bearing 30, the thrust shaft body 20, and the second thrust bearing 31 are removed in sequence. This avoids residual lubricating oil affecting the efficiency of disassembly and installation operations.

[0055] exist Figure 4In the illustrated embodiment, the cover assembly 1 includes a gasket 16, which is disposed between the cover body 10 and the end cap 11 and connected to both. By changing the thickness of the gasket 16, the distance between the cover body 10 and the end cap 11 can be precisely controlled, thereby indirectly adjusting the thrust clearance between the thrust bearing and the crankshaft 100. A suitable thrust clearance ensures that the crankshaft 100 has a certain amount of axial movement to accommodate changes such as thermal expansion and contraction under different engine operating conditions, while effectively limiting the axial movement of the crankshaft 100, ensuring the axial positioning accuracy of the crankshaft 100, enabling the various components of the engine to work in coordination, and improving the engine's power transmission efficiency and reliability.

[0056] exist Figure 6 In the illustrated embodiment, the thrust shaft assembly 2 includes a partition 23 located within the receiving space 201 and connected to the thrust shaft body 20. To ensure pressure stability within the receiving space 201 enclosed by the thrust shaft body 20, and to prevent oil oscillation within the receiving space 201 during high-speed rotation of the crankshaft 100, thereby ensuring a stable and sufficient supply of lubricating oil to the first thrust bearing 30 and the second thrust bearing 31, at least one partition 23 can be provided within the receiving space 201. If there are multiple partitions 23, their angles can be selected as vertical or inclined. Figure 6 In the embodiment shown, there are three partitions 23, and the angle of the partitions 23 is 90°. This application does not limit this.

[0057] In some embodiments, the first thrust bearing 30 and the second thrust bearing 31 include annular thrust bearings. Compared with conventional split thrust bearings, annular thrust bearings have a continuous thrust surface, which can double the load-bearing capacity and reduce the tolerance grade by more than one level for the same size.

[0058] In some embodiments, the first thrust bearing 30 and the second thrust bearing 31 include tilting pad thrust bearings. The working principle of the tilting pad thrust bearing is that the axial load of the rotating machinery is evenly transmitted to the engine mount through the hydrodynamic oil film formed between the rotating thrust shaft body 20 and the automatically tilting first thrust bearing 30 and second thrust bearing 31. Therefore, except for the rigid contact between moving and stationary parts during startup and shutdown when the hydrodynamic oil film has not yet been fully established, it is completely wear-free under normal operating conditions. This configuration can effectively improve the axial load-bearing capacity of the first thrust bearing 30 and the second thrust bearing 31.

[0059] In some embodiments, the thrust shaft body 20 can be made of lightweight, high-strength materials, such as titanium alloys, which can reduce the weight by more than 40% compared with alloy steel materials while ensuring the same strength.

[0060] In the embodiments of this application, the following assembly method can be used:

[0061] The oil supply plug 21 is assembled onto the crankshaft 100, and then the cover body 10 is fixed onto the crankshaft 100 with bolts. The cover body 10 is then assembled onto the engine block 102 with bolts, and the radial position of the cover body 10 is adjusted to ensure that the runout of the center hole of the cover body 10 relative to the center of the crankshaft 100 meets the design requirements. Subsequently, the second thrust bearing 31 (with its surface evenly coated with red lead oil) is placed into the receiving cavity 13, and then the thrust shaft body 20 is fixed with bolts. The crankshaft 100 is pried to make the second thrust bearing 31 fit against the thrust shaft body 20, and the fit between the second thrust bearing 31 and the thrust surface of the thrust shaft body 20 is checked. Place the first thrust bearing 30 (with red lead oil evenly applied to its surface) into the center hole of the end cap 11, and then fix the gasket 16 and the end cap 11 to the cover body 10 with bolts. Pry the crankshaft 100 to make the first thrust bearing 30 fit with the thrust shaft body 20, and check the fit between the first thrust bearing 30 and the thrust surface of the thrust shaft body 20.

[0062] Accordingly, this application provides an engine including the aforementioned thrust-damping structure. Therefore, this engine can possess all the technical features and beneficial effects of the aforementioned thrust-damping structure, which will not be elaborated further here.

[0063] Figure 7 This is a flowchart illustrating a design method for a thrust-stop structure according to an embodiment of this application. (Reference) Figure 7 This application also provides a method for designing a thrust-stop structure, comprising the following steps:

[0064] S1: Determine the dimensions of thrust bearing assembly 3;

[0065] The thrust bearing assembly 3 is used to withstand the axial loads generated inside and outside the engine. The dimensions of the thrust bearing assembly 3 are designed reasonably.

[0066] In some embodiments, before determining the size of the thrust bearing assembly 3 in step S1, the following step is further included: determining the form of the thrust bearing assembly 3. Exemplarily, the thrust bearing assembly 3 is matched and selected based on the required axial load capacity calculated according to different engine installation states and operating environments. In some embodiments, the first thrust bearing 30 and the second thrust bearing 31 include annular thrust bearings. Compared with conventional split thrust bearings, annular thrust bearings have a continuous thrust surface, and at the same size, the load capacity can be increased by 100%, and the tolerance grade can be reduced by more than 1 grade. In other embodiments, the first thrust bearing 30 and the second thrust bearing 31 include tilting pad thrust bearings. The working principle of the tilting pad thrust bearing is that the axial load of the rotating machinery is uniformly transmitted to the engine mount through the hydrodynamic oil film formed between the rotating thrust shaft body 20 and the automatically tilting first thrust bearing 30 and second thrust bearing 31. Therefore, except for the rigid contact between moving and stationary parts at the moment of start-up and stop due to the incomplete establishment of the hydrodynamic oil film, it is completely wear-free under normal operating conditions. This configuration can effectively improve the axial load capacity of the first thrust bearing 30 and the second thrust bearing 31.

[0067] S2: Perform load-bearing capacity verification calculations on thrust bearing assembly 3.

[0068] If the load-bearing capacity verification calculation meets the design requirements, then the currently designed thrust bearing assembly 3 can be used. If it does not meet the design requirements, then the form and dimensions of the thrust bearing assembly 3 are redefined, and the load-bearing capacity verification calculation is performed again until the design requirements are met. It is understandable that by rationally designing the dimensions of the thrust bearing assembly 3 and performing load-bearing capacity verification calculations, it can be ensured that the thrust bearing assembly 3 can work stably and reliably during engine operation, whether under constant or instantaneous axial force. This prevents malfunctions such as oil film rupture, dry friction, and abnormal wear caused by insufficient load-bearing capacity, ensuring normal engine operation and extending the service life of the thrust bearing assembly 3.

[0069] S3: Determine the dimensions of the thrust shaft body 20 in the thrust shaft assembly 2 and the dimensions of the oil hole 200 on the thrust shaft body 20;

[0070] The thrust shaft assembly 2 is used to transmit engine speed and axial load, and is responsible for providing lubricating oil from the crankshaft 100 to the thrust bearing assembly 3. In some embodiments, after confirming the dimensions of the thrust shaft body 20, it is also necessary to confirm the shaft system arrangement diagram and the shaft system equivalent parameter table for subsequent analysis.

[0071] S4: Perform shaft torsional vibration calculation and lubrication system simulation analysis on thrust shaft assembly 2.

[0072] By rationally designing the dimensions of the thrust shaft body 20 and the oil hole 200 on the thrust shaft body 20 in the thrust shaft assembly 2, on the one hand, by performing shaft system torsional vibration calculations on the thrust shaft assembly 2, it is possible to analyze whether the allowable values ​​are exceeded from the perspectives of torsional vibration mode, critical speed, torsional vibration stress, and torsional vibration amplitude. If the allowable values ​​are exceeded, the dimensions of the thrust shaft body 20 are redesigned, and the shaft system torsional vibration calculations are performed again. This setting can ensure the precise fit between the thrust shaft body 20 and the thrust bearing assembly 3 and the crankshaft 100, ensure that the strength and stiffness of the thrust shaft body 20 meet the requirements, ensure that the thrust shaft body 20 adapts to the torsional vibration environment of the engine, avoid deformation or damage during operation, reduce fatigue damage of the thrust shaft body 20, and ensure the smoothness and reliability of engine operation.

[0073] On the other hand, by conducting simulation analysis on the lubricating oil system, analyzing the lubricating oil flow and pressure in the lubricating oil system, the oil circuit design of the lubricating oil system can be optimized, and appropriate lubricating oil flow and pressure can be determined to improve the load-bearing capacity and service life of the thrust bearing assembly 3, while also reducing power loss and improving the overall efficiency of the engine.

[0074] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0075] The foregoing has provided a detailed description of a thrust-stopping structure, its design method, and an engine, and has used specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A thrust-resistant structure connected to an engine, characterized in that, The application relates to a thrust structure and a method for designing the thrust structure. The thrust structure comprises a cover assembly, a thrust shaft assembly and a thrust bearing assembly. The cover assembly comprises a cover body and an end cover connected with each other, the cover body is provided with an opening, and the end cover covers the opening and forms a containing cavity together with the cover body. The thrust shaft assembly is located in the containing cavity and comprises a thrust shaft body, the thrust shaft body is connected with a crankshaft of an engine at a side of the thrust shaft body away from the end cover.

2. The thrust structure of claim 1, wherein The thrust bearing assembly comprises a first thrust bearing and a second thrust bearing, the first thrust bearing is connected with the end cover, and at least part of the thrust shaft body is located between and connected with the first thrust bearing and the second thrust bearing. The thrust shaft assembly comprises an oil supply screw, the oil supply screw is connected with the crankshaft, and the oil supply screw is provided with an inlet.

3. The thrust structure of claim 2, wherein The thrust shaft body is provided with an oil hole and a containing space connected with the oil hole, and the inlet is connected with the containing space.

4. The thrust structure of claim 2, wherein The thrust shaft assembly is provided with a pressing plate arranged at the side of the thrust shaft body away from the end cover and connected with the thrust shaft body, the pressing plate is provided with an outlet, and the outlet is connected with the inlet and the containing space respectively. The oil hole comprises a first sub-oil hole and a second sub-oil hole. The end cover, the first thrust bearing and the thrust shaft body form a first cavity, and the first sub-oil hole is connected with the first cavity.

5. The thrust structure of claim 4, wherein The end cover, the second thrust bearing and the cover body form a second cavity, and the second sub-oil hole is connected with the second cavity. The thrust shaft body and the cover body are provided with a first outlet connected with the second cavity.

6. The thrust structure of claim 4, wherein The cover body is provided with a second outlet connected with the second cavity.

7. The thrust structure of claim 2, wherein The end cover is provided with a third outlet connected with the first cavity.

8. The thrust structure of claim 1, wherein The thrust shaft assembly is provided with a partition plate arranged in the containing space and connected with the thrust shaft body.

9. The thrust structure of claim 1, wherein The cover assembly is provided with a gasket arranged between the cover body and the end cover and connected with the cover body and the end cover respectively. The first thrust bearing and the second thrust bearing comprise a circular thrust bearing; or 10. An engine characterized by, The first thrust bearing and the second thrust bearing comprise a tilting pad thrust bearing.

11. A method of designing a thrust structure, characterized by The application relates to a thrust structure and a method for designing the thrust structure. The application relates to a thrust structure and a method for designing the thrust structure. The method comprises the following steps: Determining the size of the thrust bearing assembly; Checking the carrying capacity of the thrust bearing assembly; Determining the size of the thrust shaft body in the thrust shaft assembly and the size of the oil hole on the thrust shaft body; Carrying out shafting torsional vibration calculation and oil system simulation analysis on the thrust shaft assembly.

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