CN214092739U - Crankshaft bearing shell and internal combustion engine - Google Patents

Abstract

The application provides a crankshaft bearing shell and an internal combustion engine. The crankshaft bearing bush comprises a crankshaft upper bearing bush and a crankshaft lower bearing bush, and lower bearing bush oil grooves are formed in the inner walls of the two ends of the crankshaft lower bearing bush. The crankshaft bearing bush can effectively reduce the pressure fluctuation of lubricating oil, and is favorable for slowing down the cavitation erosion of the connecting rod bearing bush, thereby being favorable for delaying the failure of the connecting rod bearing bush and further being favorable for prolonging the service life of the connecting rod bearing bush. The shape and the size of the lower bearing bush oil grooves at the two ends of the crankshaft lower bearing bush are consistent, so that stress concentration of the crankshaft bearing bush is avoided, pressure fluctuation difference generated by lubricating oil at the connecting rod bearing bush is avoided, and the service lives of the crankshaft bearing bush and the connecting rod bearing bush can be prolonged. The internal combustion engine comprises the crankshaft bearing bush.

Description

Crankshaft bearing shell and internal combustion engine

Technical Field

The utility model relates to an internal-combustion engine technical field especially relates to a bent axle bush and internal-combustion engine.

Background

The crankshaft connecting rod mechanism is a core component of the internal combustion engine, and can convert reciprocating motion of a piston into rotary motion of a crankshaft, so that power is transmitted to the whole vehicle through a flywheel gearbox and other mechanisms. Friction exists between any objects in the presence of relative motion, and not only does friction cause wear, but it also generates heat. On the one hand, the rotating speed of the internal combustion engine is very high and can reach thousands of revolutions per minute; on the other hand, the cylinder explosion pressure transmitted by the piston is large and can reach more than 16 bars, and the friction problem between parts must be solved when the crankshaft connecting rod mechanism runs under the conditions of high rotating speed and high load.

The crankshaft bearing bush and the connecting rod bearing bush can well solve the friction problem of a crankshaft connecting rod mechanism. The crankshaft bearing shell is mounted between the crankshaft and the crankshaft bearing, and is stationary relative to the crankshaft bearing. The connecting rod bearing shell is installed between the crankshaft and the connecting rod and is static relative to the connecting rod.

On one hand, the bearing bush is made of special materials, the materials are soft, the impurity inclusion is good, the friction coefficient is small, the wear resistance is high, and the wear of related parts can be effectively reduced; on the other hand, lubricating oil can form an oil film on the surface of the bearing bush, the oil film pressure is positively correlated with the relative movement speed, the crankshaft and the bearing bush are separated from contact under the action of the oil film pressure, friction is further reduced, the oil film flows back to the oil pan through the gap between the crankshaft and the bearing bush and can take away heat generated by friction, and local overhigh temperature is avoided.

The bearing bush comprises an upper bearing bush and a lower bearing bush. Because the cylinder explosion pressure of the power stroke of the internal combustion engine is far higher than the stress of other strokes, the explosion pressure transmitted by the connecting rod can enable the lower bearing bush of the crankshaft to bear higher load, in order to avoid the influence of an oil duct on the bearing bush bearing capacity and the service life, a complete oil groove is only designed on the upper bearing bush of the crankshaft under the ordinary condition, the oil groove is matched with and penetrates through an oil duct of a main journal of the crankshaft, the oil duct can be always communicated in the 360-degree rotation process of the crankshaft, and the problem that the gap of the bearing bush of the connecting rod cannot be lubricated is avoided.

In the prior art, as shown in fig. 2, since the lower bearing shell of the crankshaft is not designed with an oil groove, only one inlet of the crankshaft main journal oil passage is connected with the oil groove of the upper bearing shell at each specific time in the 360-degree rotation process. At the moment of inlet conversion, namely when the crankshaft main journal oil passage rotates to a horizontal state, the continuity of a lubricating oil passage can be damaged, lubricating oil can generate pressure fluctuation, the pressure fluctuation is transmitted to a connecting rod bearing bush, cavitation erosion of the connecting rod bearing bush can be caused, materials on the surface of the bearing bush are peeled off due to the cavitation erosion, the peeled materials are remained between the connecting rod journal and the connecting rod bearing bush, the abrasion of the connecting rod bearing bush is further accelerated, and further more serious failure is caused. When the connecting rod journal oil passage just faces the matching area of the connecting rod upper bearing bush and the connecting rod lower bearing bush at the moment of switching the inlet, the cavitation erosion risk is higher.

SUMMERY OF THE UTILITY MODEL

To the problem among the above-mentioned prior art, this application has provided a crankshaft bearing shell and internal-combustion engine. The oil grooves are additionally arranged at the two ends of the lower bearing bush of the crankshaft, so that the pressure fluctuation of lubricating oil is effectively reduced, the cavitation erosion of the connecting rod bearing bush is favorably slowed down, the failure of the connecting rod bearing bush is favorably delayed, and the service life of the connecting rod bearing bush is favorably prolonged.

In a first aspect, the utility model provides a crankshaft bearing bush, this crankshaft bearing bush include bent axle upper bearing bush and bent axle lower bearing bush, the lower bearing bush oil groove has been seted up on the inner wall at bent axle lower bearing bush both ends. The crankshaft bearing bush can effectively reduce the pressure fluctuation of lubricating oil, and is favorable for slowing down the cavitation erosion of the connecting rod bearing bush, thereby being favorable for delaying the failure of the connecting rod bearing bush and further being favorable for prolonging the service life of the connecting rod bearing bush.

In one embodiment of the first aspect, the lower bearing oil grooves at both ends of the crankshaft lower bearing are identical in shape and size. Through the embodiment, stress concentration of the crankshaft bearing bush is avoided, pressure fluctuation difference generated by lubricating oil at the connecting rod bearing bush is avoided, and the service lives of the crankshaft bearing bush and the connecting rod bearing bush can be prolonged.

In one embodiment of the first aspect, an angle formed by the two ends of the lower bearing oil groove and the center of the circle is less than 15 degrees. Through this embodiment, the cavitation erosion of connecting rod axle bush had both been favorable to avoiding to improve the life of connecting rod axle bush, also be favorable to avoiding influencing crankshaft axle bush bearing capacity and life-span.

In an embodiment of the first aspect, the width of the lower bearing shell oil groove is equal to the width of the upper bearing shell oil groove. Through the embodiment, one end of the crankshaft main journal oil passage can smoothly transit from the upper bearing bush oil groove of the crankshaft upper bearing bush into the lower bearing bush oil groove of the crankshaft lower bearing bush without causing large pressure fluctuation of lubricating oil at the connecting rod bearing bush, so that cavitation erosion of the connecting rod bearing bush is avoided, and the service life of the connecting rod bearing bush is prolonged.

In one embodiment of the first aspect, an end of the lower bearing oil groove near the upper bearing is a lower bearing oil groove first end, an end of the lower bearing oil groove far from the upper bearing is a lower bearing oil groove second end, and a depth of the lower bearing oil groove at the lower bearing oil groove first end is equal to a depth of the upper bearing oil groove. Through the embodiment, one end of the crankshaft main journal oil passage can smoothly transit from the upper bearing bush oil groove of the crankshaft upper bearing bush into the lower bearing bush oil groove of the crankshaft lower bearing bush without causing large pressure fluctuation of lubricating oil at the connecting rod bearing bush, so that cavitation erosion of the connecting rod bearing bush is avoided, and the service life of the connecting rod bearing bush is prolonged.

In an embodiment of the first aspect, the lower bearing oil groove has a depth that gradually decreases from a lower bearing oil groove first end to a lower bearing oil groove second end. By this embodiment, the impact of the lower bearing oil groove on the bearing capacity and life of the crankshaft bearing shell can be further reduced, especially in cases where the crankshaft lower bearing shell needs to withstand higher loads.

In one embodiment of the first aspect, a sump transition section is formed at the lower bearing oil sump second end, a depth of the sump transition section gradually decreases in a direction away from the upper bearing, and a depth of a remaining portion of the lower bearing oil sump is equal to a depth of the upper bearing oil sump. By this embodiment, the impact of the lower bearing oil groove on the bearing capacity and life of the crankshaft bearing shell can be further reduced, especially in cases where the crankshaft lower bearing shell needs to withstand higher loads.

In one embodiment of the first aspect, the two ends of the oil groove transition section form an angle smaller than 5 degrees with the center of the circle. Through this embodiment, be favorable to improving bent axle bush bearing capacity and life.

In a second aspect, the present invention also provides an internal combustion engine comprising the crankshaft bearing shell of the first aspect and any of its embodiments. Through the embodiment, the pressure fluctuation of the lubricating oil is effectively reduced, and the cavitation erosion of the connecting rod bearing bush is favorably slowed down, so that the failure of the connecting rod bearing bush is favorably delayed, the service life of the connecting rod bearing bush is favorably prolonged, and the long-term stable work of an internal combustion engine is favorably realized.

In one embodiment of the second aspect, the internal combustion engine includes a crankshaft cross oil passage, the crankshaft cross oil passage includes a crankshaft main journal oil passage and a connecting rod journal oil passage which are communicated with each other, two ends of the crankshaft main journal oil passage respectively have a gap with an inner wall of the crankshaft bearing bush, the crankshaft main journal oil passage can rotate around a symmetrical center of the crankshaft bearing bush, one end of the connecting rod journal oil passage is communicated with the crankshaft main journal oil passage, the other end of the connecting rod journal oil passage has a gap with the connecting rod bearing bush, and lubricating oil from the main oil passage can enter the crankshaft main journal oil passage through the crankshaft upper bearing bush and can enter the connecting rod journal oil passage through the crankshaft main journal oil passage to lubricate the connecting rod bearing bush. Through the embodiment, the crankshaft cross oil passage, the upper bearing bush oil groove of the crankshaft upper bearing bush and the lower bearing bush oil groove of the crankshaft lower bearing bush are communicated with each other, so that lubricating oil in the internal combustion engine has a continuous oil passage, and the internal combustion engine is favorable for avoiding larger pressure fluctuation at the position of a connecting rod bearing bush of the internal combustion engine, further is favorable for slowing down cavitation erosion of the connecting rod bearing bush, is favorable for prolonging the service life of the connecting rod bearing bush, and is favorable for stably working for a long time.

Compared with the prior art, the crankshaft bearing bush and the internal combustion engine have the following beneficial effects.

1. The utility model provides a crankshaft bearing bush through set up the lower bearing bush oil groove on the inner wall at crankshaft lower bearing bush both ends, can reduce the pressure fluctuation of lubricating oil effectively, is favorable to slowing down the cave of connecting rod bearing bush and loses to be favorable to delaying the inefficacy of connecting rod bearing bush, be favorable to improving the life of connecting rod bearing bush then.

2. The shape and the size of the lower bearing bush oil grooves at the two ends of the crankshaft lower bearing bush are consistent, so that stress concentration of the crankshaft bearing bush is avoided, pressure fluctuation difference generated by lubricating oil at the connecting rod bearing bush is avoided, and the service lives of the crankshaft bearing bush and the connecting rod bearing bush can be prolonged.

3. The width of the lower bearing bush oil groove is equal to that of the upper bearing bush oil groove, so that one end of the crankshaft main journal oil passage can smoothly transit from the upper bearing bush oil groove of the crankshaft upper bearing bush into the lower bearing bush oil groove of the crankshaft lower bearing bush without causing large pressure fluctuation of lubricating oil at the connecting rod bearing bush, thereby being beneficial to avoiding cavitation erosion of the connecting rod bearing bush and further prolonging the service life of the connecting rod bearing bush.

The above-mentioned technical characteristics can be combined in various suitable ways or replaced by equivalent technical characteristics as long as the purpose of the invention can be achieved.

Drawings

The invention will be described in more detail hereinafter on the basis of embodiments and with reference to the accompanying drawings, in which:

fig. 1 shows a schematic structural view of an internal combustion engine according to an embodiment of the present invention;

FIG. 2 shows a schematic view of a prior art crankshaft bushing;

fig. 3 shows a schematic structural view of a crankshaft bearing shell according to an embodiment of the present invention;

fig. 4 shows a schematic cross-sectional view of a crankshaft bearing shell according to an embodiment of the present invention.

List of reference numerals:

1-an internal combustion engine; 2-a crankshaft; 3-a connecting rod; 4-crankshaft bearing bushes; 5-connecting rod bearing shell; 6-crankshaft main journal oil duct; 7-connecting rod journal oil passage; 41-crankshaft upper bearing bush; 42-crankshaft lower bearing bush; 51-connecting rod upper bearing bush; 52-connecting rod lower bearing bush; 411-upper bearing shoe oil groove; 421-lower bearing oil groove; 422-oil groove transition section.

In the drawings, like parts are provided with like reference numerals. The drawings are not to scale.

Detailed Description

The present invention will be further explained with reference to the accompanying drawings.

As shown in fig. 3 and 4, the present embodiment provides a crankshaft bearing shell 4, where the crankshaft bearing shell 4 includes a crankshaft upper bearing shell 41 and a crankshaft lower bearing shell 42, and lower bearing shell oil grooves 421 are opened on inner walls of two ends of the crankshaft lower bearing shell 42.

Because the lower bearing bush of the crankshaft 2 is designed with the lower bearing bush oil groove 421, the crankshaft main journal oil passage 6 rotates to a horizontal state at the inlet switching moment in the process of 360 rotations, or when one end of the crankshaft main journal oil passage 6 is transited from the upper bearing bush to the lower bearing bush, one end of the crankshaft main journal oil passage 6 can be smoothly transited from the upper bearing bush oil groove 411 to enter the lower bearing bush oil groove 421, so that the continuity of a lubricating oil passage can be ensured.

That is, the oil groove 421 of the lower bearing shell ensures the continuity of the lubricant oil passage, thereby being beneficial to avoiding the lubricant oil from generating larger pressure fluctuation, further avoiding the pressure fluctuation from being transmitted to the connecting rod bearing shell 5, and being beneficial to avoiding the cavitation erosion phenomenon of the connecting rod bearing shell 5.

Cavitation erosion can flake off material from the surface of the bearing shell, and the exfoliated material remains between the journal of the connecting rod 3 and the connecting rod bearing shell 5, which will further accelerate wear of the connecting rod bearing shell 5. Especially when the connecting rod journal oil passage 7 is just opposite to the mating area of the connecting rod upper bearing bush 51 and the connecting rod lower bearing bush 52 at the above-described inlet switching instant, the cavitation risk is higher.

Therefore, the oil groove of the crankshaft lower bearing bush 42 is provided with a continuous lubricating oil channel, which is beneficial to avoiding the cavitation erosion phenomenon of the connecting rod bearing bush 5, is beneficial to avoiding the failure of the connecting rod bearing bush 5, and is further beneficial to prolonging the service life of the connecting rod bearing bush 5.

The connecting rod bearing bush 5 with a long service life can effectively reduce the abrasion of the crankshaft 2 and the connecting rod 3, and meanwhile, a lubricating oil film on the surface of the bearing bush can reduce friction and take away heat generated by friction to avoid local overhigh temperature, so that the service life of the internal combustion engine 1 is prolonged.

Because the explosion pressure of the cylinder in the power stroke of the internal combustion engine 1 is much higher than the stress of other strokes, the explosion pressure transmitted through the connecting rod 3 can make the lower bearing bush of the crankshaft 2 bear higher load. Therefore, the length of the lower bearing shell oil groove 421 of the crankshaft 2 should not be too long, so as to avoid affecting the bearing capacity and service life of the crankshaft bearing shell 4.

In order to avoid the oil groove penetrating the crankshaft lower bearing bush 42 in the whole process, the inner walls of the two ends of the crankshaft lower bearing bush 42 are respectively provided with a lower bearing bush oil groove 421. The two lower bearing shell oil grooves 421 have a larger space therebetween, so as to avoid affecting the bearing capacity and the service life of the crankshaft bearing shell 4.

Preferably, the inner wall of the oil groove of the crankshaft lower bearing shell 42 is smooth, thereby further improving the bearing capacity and life of the crankshaft bearing shell 4.

This embodiment sets up lower bearing shell oil groove 421 through the both ends at bent axle lower bearing shell 42, reduces the pressure fluctuation of lubricating oil effectively, is favorable to slowing down the cavitation erosion of connecting rod axle bush 5 to be favorable to delaying the inefficacy of connecting rod axle bush 5, then be favorable to improving the life of connecting rod axle bush 5.

In one embodiment, as shown in fig. 3 and 4, the lower bearing oil grooves 421 at both ends of the crankshaft lower bearing 42 have the same shape and size.

The shape and size of the lower bearing oil grooves 421 at the two ends of the crankshaft lower bearing 42 are consistent, so that the stress of the crankshaft lower bearing 42 can be uniformly distributed, and the stress concentration of the crankshaft lower bearing 42 is avoided. Since the explosion pressure of the cylinder in the power stroke of the internal combustion engine 1 is much higher than the stress of other strokes, the explosion pressure transmitted through the connecting rod 3 can make the lower bearing bush 42 of the crankshaft bear higher load. The stress concentration of the crankshaft 2 will affect the bearing capacity and life of the crankshaft bearing shell 4.

Meanwhile, the lower bearing oil grooves 421 with different shapes cause different pressure fluctuations of the lubricating oil at the connecting rod bearing 5, and a severe local cavitation phenomenon occurs at a position with larger pressure fluctuations, which is not beneficial to prolonging the service life of the connecting rod bearing 5.

Through this embodiment, avoided 4 stress concentration of bent axle bushes, also be favorable to having avoided the pressure fluctuation difference that lubricating oil produced in connecting rod axle bush 5 department, can improve the life of bent axle bush 4, connecting rod axle bush 5.

In one embodiment, as shown in fig. 3 and 4, the two ends of the oil groove 421 of the lower bearing shell form an angle smaller than 15 degrees with the center of the circle.

In order to ensure the continuity of the lubricating oil passage, the length of the lower bearing oil groove 421 of the crankshaft lower bearing 42 cannot be smaller than the diameter of the crankshaft main journal oil passage 6, so as to ensure that one end of the crankshaft main journal oil passage 6 can smoothly transit from the upper bearing oil groove 411 of the crankshaft upper bearing 41 into the lower bearing oil groove 421 of the crankshaft lower bearing 42, which is favorable for avoiding different pressure fluctuations of the lubricating oil at the connecting rod bearing 5, and is favorable for avoiding cavitation erosion of the connecting rod bearing 5, thereby prolonging the service life of the connecting rod bearing 5.

Meanwhile, the length of the lower bearing shell oil groove 421 of the crankshaft lower bearing shell 42 cannot be too long, so that the bearing capacity and the service life of the crankshaft bearing shell 4 are prevented from being influenced.

According to the conclusion of long-term tests, the included angle formed between the two ends of the lower bearing bush oil groove 421 of the crankshaft lower bearing bush 42 and the circle center is less than 15 degrees.

This embodiment, both be favorable to avoiding the cavitation erosion of connecting rod axle bush 5 to improve connecting rod axle bush 5's life, also be favorable to avoiding influencing crankshaft axle bush 4 bearing capacity and life-span.

In one embodiment, as shown in FIG. 3, the width of the lower bearing shell oil groove 421 is equal to the width of the upper bearing shell oil groove 411.

In order to improve the continuity of the lubricating oil passage, the width of the lower bearing oil groove 421 of the crankshaft lower bearing 42 is equal to the width of the upper bearing oil groove 411 of the crankshaft upper bearing 41, so that one end of the crankshaft main journal oil passage 6 can smoothly transit from the upper bearing oil groove 411 of the crankshaft upper bearing 41 into the lower bearing oil groove 421 of the crankshaft lower bearing 42 without causing large pressure fluctuation of the lubricating oil at the connecting rod bearing 5, thereby being beneficial to avoiding cavitation erosion of the connecting rod bearing 5 and further improving the service life of the connecting rod bearing 5.

In one embodiment, an end of the lower bearing oil groove 421 close to the upper bearing is a first end of the lower bearing oil groove 421, an end of the lower bearing oil groove 421 far from the upper bearing is a second end of the lower bearing oil groove 421, and a depth of the lower bearing oil groove 421 at the first end of the lower bearing oil groove 421 is equal to a depth of the upper bearing oil groove 411.

Similarly, in order to improve the continuity of the lubricant oil passage, the depth of the first end of the lower bearing oil groove 421 of the lower crankshaft bearing shell 42 is equal to the depth of the upper bearing oil groove 411 of the upper crankshaft bearing shell 41, so that the one end of the crankshaft main journal oil passage 6 can smoothly transit from the upper bearing oil groove 411 of the upper crankshaft bearing shell 41 into the lower bearing oil groove 421 of the lower crankshaft bearing shell 42 without causing large pressure fluctuation of the lubricant at the connecting rod bearing shell 5, thereby being beneficial to avoiding cavitation erosion of the connecting rod bearing shell 5 and further improving the service life of the connecting rod bearing shell 5.

In one embodiment, the depth of the lower bearing oil groove 421 gradually decreases from a first end of the lower bearing oil groove 421 to a second end of the lower bearing oil groove 421.

The depth of the lower bearing oil groove 421 of the crankshaft lower bearing shell 42 gradually decreases from the first end to the second end thereof, which can further reduce the influence of the lower bearing oil groove 421 on the bearing capacity and the service life of the crankshaft bearing shell 4, especially in the case where the crankshaft lower bearing shell 42 needs to bear higher loads.

In one embodiment, as shown in fig. 4, a groove transition section 422 is formed at a second end of the lower bearing oil groove 421, the depth of the groove transition section 422 gradually decreases in a direction away from the upper bearing, and the depth of the remaining portion of the lower bearing oil groove 421 is equal to the depth of the upper bearing oil groove 411.

Similarly, the depth of the oil groove transition section 422 decreases gradually in a direction away from the upper bearing shell, which can further reduce the impact of the lower bearing shell oil groove 421 on the bearing capacity and life of the crankshaft bearing shell 4, especially in the case of the crankshaft lower bearing shell 42 needing to bear higher loads. Preferably, the second end of the lower bearing shell oil groove 421 is smoothly connected with the oil groove transition section 422.

Preferably, as shown in fig. 4, the two ends of the oil groove transition section 422 form an angle of less than 5 degrees with the center of the circle.

This contained angle undersize, oil groove changeover portion 422 can not the gentle transition, and this contained angle is too big then can cause the total length overlength of lower bearing shell oil groove 421, and both all do not do benefit to improvement bent axle bearing shell 4 bearing capacity and life-span.

According to the conclusion of long-term tests, the included angle formed between the two ends of the oil groove transition section 422 and the circle center is less than 5 degrees.

This embodiment is favorable to improving crankshaft bearing bush 4 bearing capacity and life.

The present embodiment also provides an internal combustion engine 1, and the internal combustion engine 1 includes the above-described crankshaft bearing shell 4.

In the embodiment, the lower bearing oil grooves 421 are formed at the two ends of the crankshaft lower bearing 42 of the internal combustion engine 1, so that the pressure fluctuation of lubricating oil is effectively reduced, and the cavitation erosion of the connecting rod bearing 5 is favorably slowed down, thereby being favorable for delaying the failure of the connecting rod bearing 5, further being favorable for prolonging the service life of the connecting rod bearing 5, and being favorable for the long-term stable work of the internal combustion engine 1.

In one embodiment, as shown in fig. 1, the internal combustion engine 1 includes a crankshaft cross oil passage, the crankshaft cross oil passage includes a crankshaft journal oil passage 6 and a connecting rod journal oil passage 7 which are communicated with each other, two ends of the crankshaft journal oil passage 6 respectively have a gap with an inner wall of the crankshaft bearing shell 4, the crankshaft journal oil passage 6 can rotate around a symmetrical center of the crankshaft bearing shell 4, one end of the connecting rod journal oil passage 7 is communicated with the crankshaft journal oil passage 6, and the other end thereof has a gap with the connecting rod bearing shell 5, and lubricating oil from the main oil passage can enter the crankshaft journal oil passage 6 through the crankshaft upper bearing shell 41 and can enter the connecting rod journal oil passage 7 through the crankshaft journal oil passage 6 to lubricate the connecting rod bearing shell 5.

The crankshaft bearing shell 4 is mounted between the crankshaft 2 and a bearing of the crankshaft 2, and is stationary relative to the bearing of the crankshaft 2. The connecting rod shoe 5 is mounted between the crankshaft 2 and the connecting rod 3, and is stationary relative to the connecting rod 3.

The crankshaft cross oil passage, the upper bearing bush oil groove 411 of the crankshaft upper bearing bush 41 and the lower bearing bush oil groove 421 of the crankshaft lower bearing bush 42 are communicated with each other, so that lubricating oil in the internal combustion engine 1 has a continuous oil passage, and therefore the internal combustion engine 1 is favorable for avoiding large pressure fluctuation at the connecting rod bearing bush 5 of the internal combustion engine 1, is favorable for slowing down cavitation erosion of the connecting rod bearing bush 5, is favorable for prolonging the service life of the connecting rod bearing bush 5, and is favorable for long-term stable work of the internal combustion engine 1.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "bottom", "top", "front", "rear", "inner", "outer", "left", "right", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that features described in different dependent claims and herein may be combined in ways different from those described in the original claims. It is also to be understood that features described in connection with individual embodiments may be used in other described embodiments.

Claims (7)

1. The crankshaft bearing bush is characterized by comprising a crankshaft upper bearing bush and a crankshaft lower bearing bush, wherein the inner walls of two ends of the crankshaft lower bearing bush are provided with lower bearing bush oil grooves;

the end of the lower bearing bush oil groove close to the upper bearing bush is a first end of the lower bearing bush oil groove, the end of the lower bearing bush oil groove far away from the upper bearing bush is a second end of the lower bearing bush oil groove, and the depth of the lower bearing bush oil groove at the first end of the lower bearing bush oil groove is equal to that of the upper bearing bush oil groove;

an oil groove transition section is formed at the second end of the oil groove of the lower bearing bush, the depth of the oil groove transition section is gradually reduced in the direction away from the upper bearing bush, and the depth of the rest part of the oil groove of the lower bearing bush is equal to that of the oil groove of the upper bearing bush.

2. The crankshaft bearing shell according to claim 1, wherein the lower bearing shell oil grooves at both ends of the crankshaft lower bearing shell are uniform in shape and size.

3. The crankshaft bearing shell according to claim 1, wherein the angle formed by the two ends of the oil groove of the lower bearing shell and the center of the circle is less than 15 degrees.

4. The crankshaft bearing shell of claim 1, wherein the lower bearing shell oil groove has a width equal to a width of the upper bearing shell oil groove.

5. The crankshaft bearing shell according to claim 1, wherein the angle formed by the two ends of the oil groove transition section and the center of the circle is less than 5 degrees.

6. An internal combustion engine comprising a crankshaft bearing shell according to any one of claims 1 to 5.

7. The internal combustion engine according to claim 6, comprising a crankshaft cross oil passage, wherein the crankshaft cross oil passage comprises a crankshaft main journal oil passage and a connecting rod journal oil passage which are communicated with each other, two ends of the crankshaft main journal oil passage are respectively provided with gaps with the inner wall of the crankshaft bearing bush, the crankshaft main journal oil passage can rotate around the symmetrical center of the crankshaft bearing bush, one end of the connecting rod journal oil passage is communicated with the crankshaft main journal oil passage, the other end of the connecting rod journal oil passage is provided with a gap with the connecting rod bearing bush, and lubricating oil from the main oil passage can enter the crankshaft main journal oil passage through the crankshaft upper bearing bush and can enter the connecting rod journal oil passage through the crankshaft main journal oil passage so as to lubricate the connecting rod bearing bush.

Images