Ship engine main bearing bush with high heat dissipation performance

Abstract

The invention relates to the technical field of bearing bushes, in particular to a high-heat-dissipation marine engine main bearing bush. Comprising a lower bearing bush and an upper bearing bush which are matched with each other, the lower bearing bush and the upper bearing bush are combined to form a main bearing bush assembly, inner oil grooves are formed in the inner walls of the upper bearing bush and the lower bearing bush, a main oil hole is formed in the upper bearing bush, and the output end of the main oil hole extends into the inner oil grooves; an upper oil groove is formed in the outer wall of the upper bearing bush, a lower oil groove is formed in the outer wall of the lower bearing bush, and the main oil hole is located in the upper oil groove; the inner oil groove and the outer oil groove are formed inside and outside the main bearing bush assembly, the branch groove is formed in the inner wall of the main bearing bush assembly, outer oil grooves which are communicated with each other are formed in the outer wall of the upper bearing bush and the outer wall of the lower bearing bush, and the upper oil groove and the lower oil groove are communicated through the outer oil grooves to form a cooling oil channel surrounding the outer portion of the main bearing bush assembly. Heat dissipation of the main bearing bush assembly can be more uniform, scrap iron can be efficiently discharged, and the risks of blockage and abrasion are remarkably reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of bearing bush, in particular to a high-heat-dissipation marine engine main bearing bush. BACKGROUND

[0002] The marine engine is the core of providing power for large ships, and is called the "heart" of the ship. The core component of the crankshaft rotates at high speed under heavy load, and the crankshaft bearing bush is the key "joint" that carries the crankshaft and ensures its smooth and efficient operation. As the core of the sliding bearing, the bearing bush is precisely matched with the crankshaft journal through the specially designed alloy layer on its inner wall, and a stable lubricating oil film is established between the two to withstand the impact load and reduce friction and wear. Its performance directly determines the reliability, power output and life of the engine.

[0003] However, the existing bearing bush design has a significant heat dissipation bottleneck: the lubricating oil flow is mainly limited to circulating in the oil groove of the inner wall of the bearing bush, and its main function is to establish a lubricating film, while the oil flow for cooling the body of the bearing bush is severely insufficient, which leads to a significant temperature gradient. The temperature of the outer wall of the bearing bush, which directly contacts the high-temperature journal and the combustion chamber to conduct heat, will be much higher than the temperature of the inner wall, which is continuously flushed by the lubricating oil. This large temperature difference between the inner and outer walls can generate harmful thermal stress inside the bearing bush, which may cause fatigue cracks in the alloy layer, poor fit with the bearing seat, and even serious failures such as bearing bush burning. SUMMARY

[0004] The present application provides a high-heat-dissipation marine engine main bearing bush, which solves the problem of excessive temperature difference between the inner and outer walls of the bearing bush by providing lubricating oil channels on both the inner and outer walls of the bearing bush.

[0005] To achieve the above-mentioned purpose, the high-heat-dissipation marine engine main bearing bush comprises a lower bearing bush and an upper bearing bush that cooperate with each other, and the two form a main bearing bush assembly. The inner walls of the upper bearing bush and the lower bearing bush are provided with inner oil grooves. A main oil hole is formed in the upper bearing bush, and the output end of the main oil hole extends into the inner oil groove. The outer wall of the upper bearing bush is provided with an upper oil groove, and the outer wall of the lower bearing bush is provided with a lower oil groove. The main oil hole is located in the upper oil groove. The outer walls of the upper bearing bush and the lower bearing bush are provided with an outer oil groove that communicates with each other. The upper oil groove and the lower oil groove are connected by the outer oil groove to form a cooling oil channel that surrounds the outside of the main bearing bush assembly.

[0006] In the above technical solution, two outer oil grooves are provided on the upper bearing bush and the lower bearing bush, forming two cooling oil channels, and the two cooling oil channels are symmetrically distributed along the axial direction of the main bearing bush assembly. The upper oil groove and the lower oil groove are symmetrically arranged along the center plane of the main bearing bush assembly, so that the cooling oil flow through the two outer oil grooves is basically the same, which improves the uniformity of the temperature on the main bearing bush assembly.

[0007] Based on the above, the outer wall of the lower bearing bush and the upper bearing bush is provided with a plurality of auxiliary oil grooves, and each auxiliary oil groove and the lower oil groove are provided with a auxiliary oil hole extending into the inner oil groove, a plurality of the auxiliary oil grooves are communicated with the outer oil groove, the auxiliary oil grooves, the upper oil groove and the lower oil groove are uniformly arranged along the circumference of the outer wall of the main bearing bush assembly, the diameter of the plurality of auxiliary oil holes decreases from the upper bearing bush to the lower bearing bush, so that the pressure of the lubricating oil entering the inner oil groove is more uniform.

[0008] Secondly, the inner wall of the upper bearing bush and the lower bearing bush is provided with two rows of branch grooves, the two rows of branch grooves are located on the two sides of the inner oil groove along the axial direction, and each branch groove in each row is communicated with the inner oil groove, so that the lubricating oil in the inner wall of the main bearing bush assembly is more sufficient and uniform.

[0009] Further, the branch grooves on both sides of the inner oil groove are communicated through the inner oil groove to form a continuous oil channel through the inner oil groove, and the whole continuous oil channel is curved towards the rotation direction of the journal, so as to maintain the oil pressure in the inner oil groove and the branch groove stable.

[0010] Further, the upper bearing bush and the lower bearing bush are provided with oil discharge holes on both sides, the inlet of the oil discharge hole is communicated with the inner bottom surface of the branch groove, and the channel of the oil discharge hole extends along the bending direction of the branch groove, so as to facilitate the discharge of iron filings.

[0011] Therefore, by arranging the inner oil groove and the outer oil groove in the main bearing bush assembly, and arranging the branch groove on the inner wall of the main bearing bush assembly, the heat dissipation of the main bearing bush assembly is more uniform, and the iron filings can be efficiently discharged, which significantly reduces the risk of blockage and wear.

[0012] Compared with the prior art, the beneficial effects of the present application are: 1. In the high-heat-dissipation marine engine main bearing bush, the lubricating oil first enters the lower oil groove, and when the lubricating oil flows through the outer oil groove, it exchanges heat with the outer wall of the lower bearing bush and the upper bearing bush, thereby realizing heat dissipation of the outer wall of the main bearing bush assembly. When the lubricating oil enters the inner oil groove, it also dissipates heat on the inner wall of the main bearing bush assembly, which cools the inner and outer walls of the main bearing bush assembly, effectively reducing the influence of the temperature difference between the inner and outer walls on the bearing bush assembly.

[0013] 2. In the high-heat-dissipation marine engine main bearing bush, after the lubricating oil enters the outer oil groove, it not only flows to the main oil hole, but also enters the auxiliary oil hole through the auxiliary oil groove, and then flows into the inner oil groove. This makes the lubricating oil in the outer oil groove enter the inner oil groove from multiple radial directions of the main bearing bush assembly, thereby making the oil supply pressure in each direction of the inner oil groove more balanced. At the same time, during the process of lubricating oil flowing through the auxiliary oil groove and the auxiliary oil hole, the main bearing bush assembly can be further and uniformly cooled.

[0014] 3、The high heat dissipation ship engine main bearing bush, through the branch groove bending to the inner oil tank, utilizes the rotating kinetic energy of the crankshaft, not only helps to quickly establish lubrication and stable oil pressure, but also guides the metal debris to move to the oil drain hole, combined with the design of the branch groove with gradually increasing depth and the oil drain hole, realizes the smooth discharge of the debris and the self-cleaning of the system, significantly reduces the risk of blockage and wear, in addition, by matching the highest main oil hole with the secondary oil hole with gradually decreasing hole diameter, the outlet pressure of each oil supply point is balanced by using the throttling effect, ensuring the uniform and stable oil pressure of the inner wall. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 For the overall structure of the present application Figure 1 ; Figure 2 For the overall structure of the present application Figure 2 ; Figure 3 For the overall structure of the present application Figure 4 For the overall structure of the present application Figure 5 For the overall structure of the present application Figure 4 A-A section structure schematic diagram in the present application Figure 6 For the overall structure of the present application Figure 7 For the overall structure of the present application Figure 6 A portion structure schematic diagram in the present application

[0016] The meanings of various labels in the figure are: 1, lower bearing bush; 2, upper bearing bush; 3, inner oil tank; 4, main oil hole; 5, branch groove; 6, oil drain hole; 7, outer oil tank; 8, upper oil tank; 9, lower oil tank; 10, secondary oil tank; 11, secondary oil hole. DETAILED DESCRIPTION

[0017] The technical solutions in the present application will be described clearly and completely below in combination with the drawings in the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0018] Since the existing lubricating oil flow is mainly limited to circulating in the oil groove of the inner wall of the bearing shell, its main function is to establish a lubricating film, and the oil flow for cooling the bearing shell body is seriously insufficient, which leads to a significant temperature gradient, the temperature of the outer wall of the bearing shell directly contacting the high-temperature shaft neck and the combustion chamber is much higher than that of the inner wall continuously washed by the lubricating oil, and the temperature difference between the inner and outer walls is too large to generate harmful thermal stress in the bearing shell, which may cause fatigue cracks in the alloy layer, poor bearing seat fit and even serious failure problems such as bearing shell burning.

[0019] Therefore, in view of the above-mentioned problems, the present application shows a high-heat-dissipation main bearing shell of a ship engine, referring to Figures 1-3 It is shown that it comprises a lower bearing shell 1 and an upper bearing shell 2 cooperating with each other, which combine to form a main bearing shell assembly, and the inner walls of the upper bearing shell 2 and the lower bearing shell 1 are each provided with an inner oil groove 3, and the two inner oil grooves 3 combine to form a continuous annular groove, and a main oil hole 4 is formed in the upper bearing shell 2, and the output end of the main oil hole 4 extends into the inner oil groove 3.

[0020] In work, the lubricating oil needs to enter the inner oil groove 3 from the main oil hole 4, and part of the lubricating oil in the inner oil groove 3 will flow out in the direction of the shaft end surface of the shaft neck under the action of pressure, and then form an oil film between the shaft neck and the inner wall of the main bearing shell assembly.

[0021] Referring to Figures 1-2 and Figure 5 It is shown that the outer wall of the upper bearing shell 2 is provided with an upper oil groove 8, the outer wall of the lower bearing shell 1 is provided with a lower oil groove 9, and the main oil hole 4 is located in the upper oil groove 8; the outer walls of the upper bearing shell 2 and the lower bearing shell 1 are provided with an outer oil groove 7 in communication with each other, the upper oil groove 8 and the lower oil groove 9 are communicated through the outer oil groove 7, forming a cooling oil passage around the outside of the main bearing shell assembly, and the cooling oil is lubricating oil.

[0022] In work, the lubricating oil first enters the lower oil groove 9, then flows to the outer oil groove 7, then enters the upper oil groove 8, and finally enters the inner oil groove 3 through the main oil hole 4, in this process, the lubricating oil exchanges heat with the outer walls of the lower bearing shell 1 and the upper bearing shell 2 when flowing through the outer oil groove 7, thereby achieving heat dissipation of the outer wall of the main bearing shell assembly, and when the lubricating oil enters the inner oil groove 3, it also dissipates heat from the inner wall of the main bearing shell assembly, which cools the inside and outside of the main bearing shell assembly, effectively reducing the impact of the temperature difference between the inside and outside on the bearing shell assembly.

[0023] Referring to Figures 1-2 It is shown that the outer oil groove 7 is provided with two on the upper bearing shell 2 and the lower bearing shell 1, forming two cooling oil passages, and symmetrically distributed along the axial direction of the main bearing shell assembly.

[0024] In operation, the lubricating oil entering the lower oil groove 9 will be simultaneously distributed to the two groups of outer oil grooves 7 and finally converge into the upper oil groove 8. The lubricating oil in the two groups of outer oil grooves 7 can be symmetrically distributed to the two sides of the outer wall of the main bearing bush assembly, while the inner oil groove 3 can be used to concentrate the heat dissipation to the middle area of the inner wall of the main bearing bush assembly, so that the heat dissipation of the main bearing bush assembly in the axial direction and between the inner and outer walls is more uniform and comprehensive.

[0025] Referring to Figures 1-2 The upper oil groove 8 and the lower oil groove 9 are symmetrically arranged along the center surface of the main bearing bush assembly, so that the flow of the cooling oil flowing through the two outer oil grooves 7 is basically the same, thereby avoiding the excessive concentration of the lubricating oil flowing on one side of the main bearing bush assembly, and effectively improving the uniformity of the overall heat dissipation.

[0026] Referring to Figures 1-5 The outer wall of the lower bearing bush 1 and the upper bearing bush 2 is provided with a plurality of auxiliary oil grooves 10, and each auxiliary oil groove 10 and the lower oil groove 9 are provided with an auxiliary oil hole 11 extending into the inner oil groove 3. The shapes of the main oil hole 4 and the auxiliary oil hole 11 are circular. The auxiliary oil hole 11 is used to transport lubricating oil into the inner oil groove 3. The two sides of the plurality of auxiliary oil grooves 10 are in communication with the outer oil groove 7. On the circumferential outer wall of the main bearing bush assembly, the auxiliary oil groove 10, the upper oil groove 8 and the lower oil groove 9 are uniformly arranged in the circumferential direction.

[0027] When the lubricating oil enters the outer oil groove 7, it will not only flow to the main oil hole 4, but also flow to the auxiliary oil hole 11 through the auxiliary oil groove 10, and then flow into the inner oil groove 3. This makes the lubricating oil in the outer oil groove 7 able to flow into the inner oil groove 3 from multiple radial directions of the main bearing bush assembly, thereby making the oil supply pressure in each direction in the inner oil groove 3 more balanced. At the same time, the lubricating oil flowing through the auxiliary oil groove 10 and the auxiliary oil hole 11 can further comprehensively and uniformly dissipate heat from the main bearing bush assembly.

[0028] Referring to Figure 5 The diameters of the plurality of auxiliary oil holes 11 decrease in turn from the upper bearing bush 2 to the lower bearing bush 1.

[0029] In the actual structure, since the main oil hole 4 is located at the uppermost of the main bearing bush assembly, farthest from the lower oil groove 9, the oil path has the largest resistance, so the lubricating oil pressure at this position is relatively the lowest. In order to balance the pressure of each oil supply point, the diameter of the auxiliary oil hole 11 decreases from top to bottom. The stepwise reduction of the diameter increases the local flow resistance, thereby producing a throttling effect on the lubricating oil. The oil pressure at the outlets of the main oil hole 4 and the auxiliary oil hole 11 with different diameters tends to be consistent, thereby making the oil pressure distribution of the inner wall of the main bearing bush assembly more uniform, and improving the lubrication stability and overall lubrication effect of the journal.

[0030] Referring to Figures 1-3As shown, two rows of branch grooves 5 are provided on the inner walls of the upper bearing 2 and the lower bearing 1. The two rows of branch grooves 5 are located on both sides of the inner oil groove 3 along the axial direction, and each branch groove 5 in each row is connected to the inner oil groove 3.

[0031] When the lubricating oil enters the inner oil groove 3, a portion of it will be diverted to the branch grooves 5 on both sides. This design not only provides more sufficient lubricating oil coverage to the inner wall of the main bearing assembly, ensuring a stable lubrication effect, but also further enhances the heat dissipation efficiency of the upper bearing 2 and the lower bearing 1.

[0032] The branch grooves 5 located on both sides of the inner oil groove 3 are connected through the inner oil groove 3 to form a continuous oil passage that runs through the inner oil groove 3, and the entire continuous oil passage is bent in the direction of journal rotation.

[0033] In the initial stage of crankshaft startup, the curved structure, compared to the straight groove design perpendicular to the inner oil groove 3, can reduce the initial resistance when the journal rotates, which is conducive to the rapid establishment of lubrication. During the continuous rotation stage, the rotation of the journal will actively pump the lubricating oil along the curved branch groove 5 to the inner oil groove 3, thereby maintaining the stability of the oil pressure in the inner oil groove 3 and the branch groove 5. On the other hand, if there are fine metal debris on the inner walls of the upper bearing 2 and the lower bearing 1, the rotating flow field can push the debris along the curved channel toward the inner oil groove 3, avoiding its deposition in the branch groove 5, thereby reducing the risk of wear caused by debris retention and further improving the reliability and service life of the bearing.

[0034] Reference Figure 6 As shown, oil drain holes 6 are provided on both sides of the upper bearing 2 and the lower bearing 1. The cross-sectional shape of the oil drain hole 6 is rectangular or circular. The inlet of the oil drain hole 6 is connected to the inner bottom surface of the branch groove 5, and the channel of the oil drain hole 6 extends along the bending direction of the branch groove 5, and is also in a bent state.

[0035] After the lubricating oil enters the branch groove 5, some of the lubricating oil will also enter the drain hole 6 and then be discharged from the drain hole 6. When the lubricating oil passes through the drain hole 6, it can further dissipate heat for the upper bearing 2 and the lower bearing 1. The iron filings accumulated in the branch groove 5 can be discharged from the drain hole 6, so that the iron filings can be cleaned in time, effectively protecting the upper bearing 2 and the lower bearing 1.

[0036] Reference Figure 6 and Figure 7 As shown, the bottom of the branch groove 5 is a sloping surface, and its depth gradually increases from the connection with the inner oil groove 3 towards the oil drain hole 6.

[0037] Since the depth of the branch groove 5 near the one side of the inner oil groove 3 is shallow, the structure forms a higher flow barrier near the inner oil groove 3, which can more effectively block the high-pressure lubricating oil from leaking to both sides, thereby being conducive to maintaining the high oil film pressure of the center load-carrying area. At the same time, the depth of the branch groove 5 gradually increases from the shallow side to the direction of the oil drain hole 6, which constitutes a gradually expanding flow channel, which provides a smooth discharge path for the iron filings, making it easier for them to flow out with the lubricating oil, thereby effectively reducing the risk of the oil drain hole 6 being blocked.

[0038] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above-mentioned embodiments, and the above-mentioned embodiments and descriptions in the specification are only preferred examples of the present application and are not intended to limit the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A high heat dissipation marine engine main bearing, comprising a lower bearing (1) and an upper bearing (2) that cooperate with each other, the two being combined to form a main bearing assembly, characterized in that: The inner walls of the upper bearing (2) and the lower bearing (1) are provided with inner oil grooves (3), and the upper bearing (2) is provided with a main oil hole (4), the output end of which extends into the inner oil groove (3); The outer wall of the upper bearing (2) is provided with an upper oil groove (8), the outer wall of the lower bearing (1) is provided with a lower oil groove (9), and the main oil hole (4) is located in the upper oil groove (8); The outer walls of the upper bearing (2) and the lower bearing (1) are provided with interconnected outer oil grooves (7). The upper oil groove (8) and the lower oil groove (9) are connected through the outer oil grooves (7) to form a cooling oil channel surrounding the outside of the main bearing assembly.

2. The high heat dissipation marine engine main bearing according to claim 1, characterized in that: The outer oil groove (7) is provided in two on both the upper bearing shell (2) and the lower bearing shell (1), forming two cooling oil channels, and is symmetrically distributed along the axial direction of the main bearing shell assembly.

3. The high heat dissipation marine engine main bearing according to claim 2, characterized in that: The upper oil groove (8) and the lower oil groove (9) are symmetrically arranged along the middle split surface of the main bearing assembly so that the flow rate of cooling oil flowing through the outer oil grooves (7) on both sides is basically the same.

4. The high heat dissipation marine engine main bearing according to claim 1, characterized in that: The outer walls of the lower bearing (1) and the upper bearing (2) are provided with multiple auxiliary oil grooves (10), and each auxiliary oil groove (10) and the lower oil groove (9) are provided with auxiliary oil holes (11) extending into the inner oil groove (3). The multiple auxiliary oil grooves (10) are all connected to the outer oil groove (7).

5. The high heat dissipation marine engine main bearing according to claim 4, characterized in that: On the outer circumferential wall of the main bearing assembly, the auxiliary oil groove (10), the upper oil groove (8) and the lower oil groove (9) are evenly arranged circumferentially.

6. The high heat dissipation marine engine main bearing according to claim 5, characterized in that: The diameter of the plurality of auxiliary oil holes (11) decreases sequentially from the upper bearing (2) to the lower bearing (1).

7. The high heat dissipation marine engine main bearing according to claim 1, characterized in that: The inner walls of the upper bearing (2) and the lower bearing (1) are provided with two rows of branch grooves (5). The two rows of branch grooves (5) are located on both sides of the inner oil groove (3) along the axial direction, and each branch groove (5) in each row is connected to the inner oil groove (3).

8. The high heat dissipation marine engine main bearing according to claim 7, characterized in that: The branch grooves (5) located on both sides of the inner oil groove (3) are connected through the inner oil groove (3) to form a continuous oil passage that runs through the inner oil groove (3), and the entire continuous oil passage is bent in the direction of journal rotation.

9. The high heat dissipation marine engine main bearing according to claim 8, characterized in that: Oil drain holes (6) are provided on both sides of the upper bearing (2) and the lower bearing (1). The inlet of the oil drain hole (6) is connected to the inner bottom surface of the branch groove (5), and the channel of the oil drain hole (6) extends along the bending direction of the branch groove (5).

10. The high heat dissipation marine engine main bearing according to claim 9, characterized in that: The bottom of the branch groove (5) is a sloping surface, and its depth gradually increases from the connection with the inner oil groove (3) toward the oil drain hole (6).

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