CN110285143B

CN110285143B - Main bearing bush and mounting structure

Info

Publication number: CN110285143B
Application number: CN201910580556.5A
Authority: CN
Inventors: 李建锋; 赵鹏
Original assignee: Weichai Power Co Ltd
Current assignee: Weichai Power Co Ltd
Priority date: 2019-06-28
Filing date: 2019-06-28
Publication date: 2021-04-16
Anticipated expiration: 2039-06-28
Also published as: CN110285143A

Abstract

The invention belongs to the technical field of engines and discloses a main bearing bush and a mounting structure thereof. This main bearing bush, including upper bearing bush and lower bearing bush, the both ends of upper bearing bush butt respectively in the both ends of lower bearing bush, and the upper bearing bush includes first transition portion and two supporting parts, and the both ends of first transition portion are connected respectively in two supporting parts, and the axial width of first transition portion is less than the axial width of supporting part. The upper bearing bush of the main bearing bush adopts a variable cross section mode, reduces partial cross section of the upper bearing bush, is used for reducing the contact area of the upper bearing bush and a main journal of a crankshaft, and reduces the friction force between the upper bearing bush and the main journal of the crankshaft so as to reduce the friction loss. Meanwhile, compared with the prior art, on the premise of ensuring the strength of the upper bearing bush, the weight of the upper bearing bush is reduced equivalently, and the effect of reducing weight is achieved, so that the dead weight and the oil consumption of the whole automobile are reduced, and the aims of improving the net output power of an engine and reducing the oil consumption are fulfilled.

Description

Main bearing bush and mounting structure

Technical Field

The invention relates to the technical field of engines, in particular to a main bearing bush and a mounting structure thereof.

Background

In the working process of an engine, the stress of a main bearing of a crankshaft is mainly influenced by the explosion pressure of the engine and the inertia force of a crank connecting rod mechanism, wherein the lower bearing bush of the main bearing needs to bear the double influences of the explosion pressure and the inertia force of the engine, but the upper bearing bush of the main bearing mainly bears the inertia force, and the oil film bearing pressure is very small. The existing upper bearing bush of the main bearing has the following defects:

firstly, the design safety margin of the upper bearing bush of the main bearing is too much, which causes waste, and more importantly, the friction force generated by the large contact area between the upper bearing bush of the main bearing and the main journal of the crankshaft is large, so that the friction loss of the crank connecting rod mechanism of the engine is more.

Secondly, the main bearing upper tile is generally provided with a through type oil groove, oil holes communicated with the oil groove are arranged at different positions of the oil groove, and the cross section shapes and sizes of the main bearing upper tile at other positions are basically consistent except the oil hole positions. The oil groove is not arranged on the lower bearing of the main bearing, and the oil groove changes rapidly from existence to nonexistence on the end face of the upper bearing of the main bearing combined with the lower bearing of the main bearing, so that the formation of an oil film is not facilitated. Meanwhile, the sudden change of the oil film bearing pressure is severe, so that the oil film bearing pressure is easy to peel off from an alloy coating of a bearing bush, the service life is shortened, and large lubricating oil leakage is easy to occur at the joint end face of an upper bearing bush and a lower bearing bush of the main bearing.

Disclosure of Invention

The invention aims to provide a main bearing bush and a mounting structure, which are used for reducing the self weight and reducing the friction force between an upper bearing bush and a crankshaft so as to reduce the friction loss.

In order to achieve the purpose, the invention adopts the following technical scheme:

the utility model provides a main bearing axle bush, includes upper bearing shell and lower axle bush, the both ends of upper bearing shell respectively the butt in the both ends of lower axle bush, upper bearing shell includes first transition portion and two supporting parts, the both ends of first transition portion are connected respectively in two the supporting part, the axial width of first transition portion is less than the axial width of supporting part.

Preferably, the axial width of the first transition portion gradually decreases from the two ends to the middle in the circumferential direction of the first transition portion.

Preferably, the upper bearing shell is provided with an oil hole for introducing lubricating oil, and the inner wall of the upper bearing shell is provided with an oil groove communicated with the oil hole.

Preferably, a transition structure is disposed between at least one end of the oil groove and the lower bearing shell, and is used for transferring the lubricating oil in the oil groove to the inner surface of the lower bearing shell.

Preferably, the transition structure is a wedge-shaped block, the wedge-shaped block is arranged in the oil groove and located at the end of the oil groove, and the thickness of the wedge-shaped block gradually increases towards the direction close to the lower bearing shell.

To achieve the purpose, the invention further provides a mounting structure, which comprises an engine body and the main bearing bush, wherein an upper bearing bush of the main bearing bush is mounted on the engine body.

Preferably, the engine body comprises two fixing portions and a connecting arm, two ends of the connecting arm are respectively connected to the two fixing portions, an accommodating groove is formed in the connecting arm, and the accommodating groove is used for accommodating an upper bearing bush of the main bearing bush.

Preferably, a second transition portion is provided on the connecting arm, the second transition portion having a cross section smaller than that of the fixing portion.

Preferably, the inner surface of the accommodating groove is attached to the outer circumferential surface of the upper bearing bush, and the inner surface of the accommodating groove is matched with the outer circumferential surface of the upper bearing bush.

Preferably, the fixing portion is provided with a positioning groove, the positioning groove is communicated with the accommodating groove, a positioning block is arranged on the outer wall of the upper bearing bush and corresponds to the positioning groove, and the positioning block is clamped in the positioning groove.

The invention has the beneficial effects that:

according to the main bearing bush provided by the invention, the axial width of the first transition part is smaller than that of the support part, and the upper bearing bush adopts a variable cross section mode, so that the partial cross section of the upper bearing bush is reduced, the contact area between the upper bearing bush and the main journal of the crankshaft is reduced, the friction force between the upper bearing bush and the main journal of the crankshaft is reduced, and the friction loss is reduced. Meanwhile, compared with the prior art, on the premise of ensuring the strength of the upper bearing bush, the weight of the upper bearing bush is reduced equivalently, and the effect of reducing weight is achieved, so that the dead weight and the oil consumption of the whole automobile are reduced, and the aims of improving the net output power of an engine and reducing the oil consumption are fulfilled.

The invention also provides a mounting structure which comprises the engine body and the main bearing bush, wherein an upper bearing bush of the main bearing bush is mounted on the engine body. The mounting structure is used for reducing the self weight, meets the requirement of light weight, can reduce the dead weight oil consumption, reduces the friction force between the upper bearing bush and the crankshaft, reduces the friction loss and achieves the purpose of improving the efficiency of the engine.

Drawings

FIG. 1 is a schematic view of a perspective view of an upper shell of a main bearing shell according to the present invention;

FIG. 2 is a schematic view of another perspective of the upper shell of the main bearing shell of the present invention;

FIG. 3 is a top plan view of the upper shell of the main bearing shell of the present invention;

FIG. 4 is a schematic view of a perspective view of the engine block in the mounting arrangement of the present invention;

fig. 5 is a bottom view of the engine body in the mounting structure of the present invention.

In the figure:

1. an upper bearing bush; 2. a wedge block; 3. an engine body;

11. a support portion; 12. a first transition portion; 13. a first groove; 14. an oil hole; 15. an oil sump; 16. positioning blocks;

31. a fixed part; 32. a connecting arm;

311. positioning a groove;

321. accommodating grooves; 322. a second groove.

Detailed Description

In order to make the technical problems solved, technical solutions adopted and technical effects achieved by the present invention clearer, the technical solutions of the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.

The present embodiment provides a main bearing shell for reducing friction losses. As shown in fig. 1, the main bearing shell includes an upper shell 1 and a lower shell (not shown), wherein two ends of the upper shell 1 respectively abut against two ends of the lower shell to form a circular ring structure, and the circular ring structure is used for the crankshaft to pass through. The whole upper bearing bush 1 is of a semicircular structure, the upper bearing bush 1 specifically comprises two supporting portions 11 and a first transition portion 12, two ends of the first transition portion 12 are respectively connected to the two supporting portions 11, and in order to save production cost, preferably, the two supporting portions 11 and the first transition portion 12 are of an integrally formed structure. Since the upper shell 1 is mainly subjected to inertial forces, the axial width of the first transition portion 12 is made smaller than the axial width of the support portion 11 in order to avoid unnecessary waste.

In the main bearing bush provided by the embodiment, the axial width of the first transition portion 12 is smaller than the axial width of the support portion 11, and the upper bearing bush 1 adopts a variable cross section mode to reduce a partial cross section of the upper bearing bush 1, so as to reduce the contact area between the upper bearing bush 1 and the main journal of the crankshaft, reduce the friction force between the upper bearing bush 1 and the main journal of the crankshaft, and reduce the friction loss. Meanwhile, compared with the prior art, on the premise of ensuring the strength of the upper bearing bush 1, the weight of the upper bearing bush 1 is reduced, and the effect of reducing weight is achieved, so that the dead weight and oil consumption of the whole automobile are reduced, and the aims of improving the net output power of an engine and reducing the oil consumption are fulfilled.

In the circumferential direction of the first transition portion 12, the axial width of the first transition portion 12 gradually decreases from the two ends to the middle. Further, as shown in fig. 1-2, in the upper bearing shell 1, on the basis of the existing general main bearing upper bearing shell 1, at least one side of the middle region of the upper bearing shell 1 is provided with a first groove 13, along the circumferential direction of the upper bearing shell 1, the solid part of the upper bearing shell 1 located between the first grooves 13 forms the first transition part 12, and the two support parts 11 are respectively located at two sides of the first groove 13. Alternatively, the first groove 13 is of an arc-shaped structure, and in practical production, a certain part can be cut by arcs of the same diameter on both sides of the upper bearing shell 1, so that the first transition part 12 has an arc-shaped part which is of a variable cross-section structure, and the rest is still of a uniform cross-section structure. The cross section of the first transition part 12 is large in cross section size at two ends and small in cross section size at the middle, and by adopting the mode, the arc cutting production cost is low while the structure is attractive, and the arc structure plays a role in guiding and transition.

It should be noted that, arc cutting is performed on both sides of the upper bearing shell 1, wherein both sides do not refer to the sides where the upper bearing shell 1 abuts against the lower bearing shell, and specifically refer to the sides along the upper bearing shell 1 as shown in fig. 3, and this part corresponds to the working area of the upper bearing shell 1 for the crankshaft.

In order to ensure the lubricating effect between the upper bearing and the crankshaft, as shown in fig. 1-2, an oil hole 14 is formed in the upper bearing shell 1, the oil hole 14 is used for introducing lubricating oil, an oil groove 15 is formed in the inner wall of the upper bearing shell 1, the oil groove 15 is communicated with the oil hole 14, and the lubricating oil flows into the oil groove 15 through the oil hole 14, in this embodiment, a section of the oil groove 15 is provided on each of the first transition portion 12 and the two supporting portions 11. Because current upper bearing shell 1 adopts through-type oil groove 15, does not set up oil groove 15 on the main bearing lower shell, and the terminal surface department that the tile and the main bearing lower shell combined together appear suddenly easily on the main bearing, in order to solve this problem, the oil groove 15 of main bearing upper bearing shell 1 in this embodiment is not adopted through-type oil groove 15, is provided with transition structure between at least one end of oil groove 15 and lower shell for pass through the lubricating oil in the oil groove 15 to the internal surface of lower shell.

Further, the transition structure is the wedge 2, and the wedge 2 sets up in oil groove 15 and is located its tip position, and the thickness of wedge 2 increases to the direction that is close to lower axle bush gradually, and wherein the thickness of wedge 2 specifically means along the groove depth direction of oil groove 15. Under the guiding action of the inclined plane of the wedge-shaped block 2, the lubricating oil in the oil groove 15 is enabled to be transited to the inner surface of the lower bearing bush through the wedge-shaped block 2. Through setting up wedge 2, wedge 2 has played the effect of transition, has avoided oil groove 15 from having to not having the condition of violent change, is favorable to the formation of oil film. Meanwhile, under the diversion transition effect of the wedge-shaped block 2, the condition that the oil film bearing pressure is easy to change suddenly is reduced, the oil film bearing pressure is in smooth transition, the bearing bush alloy coating is reduced from peeling, the protective coating effect is achieved, the service life is prolonged, the leakage amount of end face lubricating oil can be reduced, the oil pumping power consumption of the lubricating oil is reduced, and the power and the durability of an engine are improved.

Preferably, the thickness of the wedge block 2 on the side close to the lower bearing shell is the same as the groove depth of the oil groove 15, which is equivalent to the end of the oil groove 15 in the upper bearing shell 1 is filled by the wedge block 2, so that the upper bearing shell 1 is flush with the lower bearing shell at the position of the oil groove 15. By adopting the arrangement, the change degree of the oil groove 15 at the end face of the combination of the upper bearing shell of the main bearing and the lower bearing shell of the main bearing is further reduced, and the smooth formation of an oil film is ensured.

It should be noted that, in order to reduce the production cost, it is preferable that the main bearing upper shell 1 and the wedge 2 are integrally formed, and in actual production, when the oil groove 15 is machined on the inner wall of the main bearing upper shell 1, the wedge 2 may be formed at both ends of the oil groove 15.

The present embodiment also provides a mounting structure, as shown in fig. 4, which includes an engine block 3 and a main bearing shell, and an upper shell 1 of the main bearing shell is mounted on the engine block 3. The mounting structure is used for reducing the self weight, meets the requirement of light weight, can reduce the dead weight oil consumption, reduces the friction force between the upper bearing bush 1 and the crankshaft, reduces the friction loss and achieves the purpose of improving the efficiency of the engine.

Further, the engine body 3 includes a connecting arm 32 and two fixing portions 31, two ends of the connecting arm 32 are respectively connected to the two fixing portions 31, an accommodating groove 321 is provided on the connecting arm 32, and the accommodating groove 321 is used for accommodating the upper bearing bush 1 of the main bearing bush. A second transition is provided on the connecting arm 32, the cross section of which is smaller than the cross section of the fixing portion 31. Compared with the prior art, on the premise of ensuring the engine body 3, the weight of the engine body 3 is reduced equivalently, and the effect of reducing weight is achieved, so that the dead weight and the oil consumption of the whole vehicle are reduced, and the aims of improving the net output power of the engine and reducing the oil consumption are fulfilled.

The inner surface of the accommodating groove 321 is attached to the outer peripheral surface of the upper bearing bush 1, and the inner surface of the accommodating groove 321 is matched with the outer peripheral surface of the upper bearing bush 1. Further, on the basis of the existing engine body 3, the engine body 3 is provided with a second groove 322 at least on one side of the middle area of the engine body 3, in this embodiment, at least one side of the middle area of the engine body 3 is provided with two second grooves 322, the solid part between the two second grooves 322 forms the second transition portion, and the two fixing portions 31 are respectively located on two sides of the second grooves 322. Alternatively, the second groove 322 has an arc-shaped structure, and in actual production, a certain portion may be cut by arcs of the same diameter on both sides of the engine body 3, so that the second transition portion has an arc-shaped portion, the portion has a variable cross-section structure, and the rest portion has a constant cross-section structure.

It can be understood that, under the prerequisite that upper bearing shell 1 set up first recess 13, for upper bearing shell 1 can install at engine body 3, the diameter of second recess 322 is preferred the same with the diameter of first recess 13 for upper bearing shell 1 and engine body 3's side keeps the parallel and level, adopts this kind of mode, and when the structure is pleasing to the eye, cutting circular arc manufacturing cost is lower, and the circular arc structure has played the effect of direction and transition.

It should be noted that, in the case of performing arc cutting on both sides of the engine body 3, the two sides do not refer to the two sides of the engine body 3 connected with the fixing portion 31, and specifically refer to the two sides along the engine body 3 as shown in fig. 5, and this part corresponds to the working area of the engine body 3 for supporting the upper bearing bush 1.

In order to ensure the installation stability of the upper bearing bush 1 and the engine body 3, optionally, a positioning groove 311 is formed in the fixing portion 31, the positioning groove 311 is communicated with the receiving groove 321, a positioning block 16 is arranged on the outer wall of the upper bearing bush 1 corresponding to the positioning groove 311, and the positioning block 16 is clamped in the positioning groove 311 to perform positioning and fixing functions. Preferably, the positioning slot 311 and the positioning block 16 may be both wedge-shaped.

In the description herein, it is to be understood that the terms "upper", "lower", "right", and the like are based on the orientations and positional relationships shown in the drawings and are used for convenience in description and simplicity in operation, but do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be constructed in a particular operation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used merely for descriptive purposes and are not intended to have any special meaning.

In the description herein, references to the description of "an embodiment," "an example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example.

In addition, the foregoing is only the preferred embodiment of the present invention and the technical principles applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A main bearing bush comprises an upper bush (1) and a lower bush, wherein two ends of the upper bush (1) are respectively abutted against two ends of the lower bush, the main bearing bush is characterized in that the upper bush (1) comprises a first transition part (12) and two supporting parts (11), two ends of the first transition part (12) are respectively connected to the two supporting parts (11), and the axial width of the first transition part (12) is smaller than that of the supporting parts (11); the axial width of the first transition part (12) is gradually reduced from two ends to the middle along the circumferential direction of the first transition part (12);

an oil groove (15) is formed in the inner wall of the upper bearing bush (1), and a transition structure is arranged between at least one end of the oil groove (15) and the lower bearing bush and used for enabling lubricating oil in the oil groove (15) to be transited to the inner surface of the lower bearing bush.

2. The main bearing shell according to claim 1, wherein an oil hole (14) is provided in the upper bearing shell (1), the oil hole (14) being adapted for letting in lubricating oil, the oil groove (15) being in communication with the oil hole (14).

3. The main bearing shell according to claim 1, wherein the transition structure is a wedge-shaped block (2), the wedge-shaped block (2) being arranged in the oil groove (15) at an end position thereof, the thickness of the wedge-shaped block (2) increasing towards the lower shell.

4. A mounting structure, characterized by comprising an engine block (3) and a main bearing shell according to any of claims 1-3, the upper shell (1) of the main bearing shell being mounted on the engine block (3).

5. The mounting structure according to claim 4, wherein the engine block (3) comprises two fixing portions (31) and a connecting arm (32), wherein the connecting arm (32) is connected at both ends to the two fixing portions (31), respectively, and wherein a receiving groove (321) is provided in the connecting arm (32), and wherein the receiving groove (321) is adapted to receive the upper shell (1) of the main bearing shell.

6. The mounting structure according to claim 5, characterized in that a second transition is provided on the connecting arm (32), the second transition having a cross section smaller than the cross section of the fixing portion (31).

7. The mounting structure according to claim 5, wherein an inner surface of the receiving groove (321) is in contact with an outer circumferential surface of the upper shell (1), and an inner surface of the receiving groove (321) is matched with the outer circumferential surface of the upper shell (1).

8. The mounting structure according to claim 5, wherein a positioning groove (311) is formed in the fixing portion (31), the positioning groove (311) is communicated with the receiving groove (321), a positioning block (16) is disposed on an outer wall of the upper bearing shell (1) corresponding to the positioning groove (311), and the positioning block (16) is engaged with the positioning groove (311).