Connecting rod small end device for high speed high power diesel engine

Abstract

The utility model relates to a kind of for high-speed high-power diesel engine connecting rod small head device, it includes: body, body is the connecting rod small head for connecting piston pin, through piston pin and piston form hinged connection, when engine works, reciprocating motion's alternating load is borne, body is used to place the bottom hole of piston pin;Bushing, bottom hole is provided with bushing, after embedding bushing in the bottom hole of connecting rod small head body, it is slidably connected with piston pin;Small head oil inlet structure, oil hole for being connected into lubricating oil is provided on the side wall of body and bushing, for being connected into lubricating oil;Oil line, oil pool, oil hole is provided on the side wall of bushing Oil line and oil pool, which is connected with oil line, the width size of oil pool is greater than the width size of oil line. According to the connecting rod small head device for high-speed high-power diesel engine of the utility model, the lubrication stability of connecting rod small head, solve the type diesel engine connecting village small head bushing rotation, ablation, abnormal wear, loosening and other problems, can improve the stability and reliability of diesel engine etc.

Description

Technical Field

[0001] This utility model relates to the field of mechanical product design technology, and more specifically, to a small end device for connecting rods of high-speed, high-power diesel engines. Background Technology

[0002] The connecting rod is a key component of a high-speed, high-power diesel engine. Its function is to connect the crankshaft and the piston: transmitting the force acting on the piston to the crankshaft and converting the piston's linear reciprocating motion into the crankshaft's rotational motion, bearing significant alternating loads. The small end of the connecting rod is an important component of the internal combustion engine connecting rod assembly. It forms a hinged connection with the piston through the piston pin and bears the alternating loads of reciprocating motion during engine operation. The small end of the connecting rod bears the closest mechanical connection and lubrication guarantee between the piston and the crankshaft. Its structure adopts a thin-walled cylindrical design to accommodate piston pin assembly. The material is mostly medium carbon steel or alloy steel, manufactured through die forging / roll forging processes. Design requirements include fatigue strength, structural rigidity, and lightweight indicators. It must withstand combined stresses such as compression, tension, and bending to avoid lubrication failure caused by insufficient strength leading to connecting rod body fracture or large end deformation.

[0003] Currently, diesel engine connecting rods are connected to the piston via piston pins and employ splash lubrication. Lubricating oil splashes through two oil holes and both sides of the small end bushing hole, providing lubrication and cooling for the small end bushing-piston pin friction pair. However, during engine testing, problems such as connecting rod small end bushing rotation, burning, abnormal wear, and loosening frequently occur, severely affecting the stability and reliability of the diesel engine. Research and analysis have revealed that these problems are mainly caused by insufficient lubrication and cooling, difficulty in forming an effective oil film between the piston pin and the connecting rod small end bushing hole, easy wear of the small end bushing-piston pin friction pair, and insufficient holding force between the bushing and the bottom hole.

[0004] Therefore, there is an urgent need to develop a connecting rod small end solution to improve the lubrication and cooling of the connecting rod small end, enhance the uniformity and stability of the oil film on the friction pair between the small end bushing and the piston pin, improve the wear resistance of the friction pair between the small end bushing and the piston pin, and improve the holding force between the small end bushing and the bottom hole, thereby solving problems such as the rotation, burning, abnormal wear, and loosening of the connecting rod small end bushing. Summary of the Invention

[0005] The technical problem to be solved by this utility model is the problems of connecting rod small end bushing rotation, ablation, abnormal wear, and loosening. It also addresses how to improve the lubrication and cooling of the connecting rod small end, enhance the uniformity and stability of the oil film between the small end bushing and the piston pin friction pair, improve the wear resistance of the small end bushing and piston pin friction pair, and improve the holding force between the small end bushing and the bottom hole.

[0006] To solve the above-mentioned technical problems, this utility model provides a connecting rod small end device for a high-speed, high-power diesel engine, comprising: a body, which is a connecting rod small end for connecting to a piston pin, forming a hinge connection with the piston pin, and bearing the alternating load of reciprocating motion when the engine is working; a bushing, in which a bushing is installed in the bottom hole, and the bushing is slidably connected to the piston pin after being embedded in the bottom hole of the connecting rod small end body; a small end oil inlet structure, in which oil holes are provided on the side walls of the body and the bushing for connecting lubricating oil; an oil line and an oil sump, in which an oil line connected to the oil hole and an oil sump connected to the oil line are provided on the side wall of the bushing, and the width of the oil sump is larger than the width of the oil line. The lubricating oil is introduced through the oil hole of the small end oil inlet structure and can be temporarily stored in the oil line and the oil sump to ensure long-term and stable lubrication between the piston pin and the connecting rod small end.

[0007] According to an embodiment of this utility model, the width of the oil line perpendicular to the direction of lubricating oil flow can be greater than the diameter of the oil hole to facilitate the entry of lubricating oil.

[0008] According to an embodiment of this utility model, one end of the oil line can be connected to an oil hole, and the other end can be connected to an oil tank.

[0009] According to an embodiment of this utility model, two oil holes, two oil lines, and two oil pools can be provided.

[0010] According to an embodiment of the present invention, lubricating oil can enter the oil line and oil sump through the oil hole in the main body and the oil hole in the bushing. The inner walls of the two ends of the bushing in the axial direction are widened outward with a 3-degree chamfer to allow more lubricating oil to be stored in the bushing hole, thereby enhancing the friction reduction, lubrication and cooling capabilities of the bushing and piston pin.

[0011] According to an embodiment of the present invention, an interference fit can be used between the bushing and the bottom hole of the body.

[0012] According to an embodiment of this utility model, the allowable clearance between the bushing and the bottom hole of the body can be set to 0.106-0.132mm, which is used to strengthen the holding force between the small end bushing and the bottom hole, improve the reliability of the assembly of the small end bushing and the bottom hole, and make it difficult for loosening, rotation, or falling off to occur.

[0013] According to an embodiment of this utility model, the axial profile of the inner wall of the bushing can be designed into three segments, including: an inclined segment at angle a, a straight segment, and an inclined segment at angle b arranged sequentially. This is used to ensure that the bushing hole and the piston pin maintain a relatively uniform gap during actual operation, thereby making it easier to form a uniform and stable lubricating oil film and ensuring the reliability of lubrication of the bushing hole-piston pin friction pair. The angles a and b are not greater than 3°.

[0014] According to an embodiment of the present invention, the bushing ends can be provided with a 4×3° chamfer to make it easier for more lubricating oil to enter the bushing from both ends of the bushing hole.

[0015] According to an embodiment of this utility model, the surface finish of the oil hole conical surface of the body can be set to Ra1.6, and the transition point with the straight hole is rounded by R2, so that the lubricating oil can enter the bushing more quickly and smoothly through the straight hole, and provide lubrication for the friction between the bushing oil hole and the piston pin in a timely manner.

[0016] According to an embodiment of this utility model, the bushing material can be a copper alloy.

[0017] Compared with the prior art, the technical solution provided by the embodiments of this utility model can achieve at least the following beneficial effects:

[0018] The connecting rod small end device for high-speed, high-power diesel engines according to this utility model improves the connecting rod small end structure by setting a small end oil inlet structure, oil line, and oil sump, thereby increasing the lubrication stability of the connecting rod small end. After whole-machine testing and verification, it solves the problems of connecting rod small end bushing rotation, burning, abnormal wear, and loosening in this type of diesel engine, and can improve the stability and reliability of the diesel engine. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings of the embodiments will be briefly introduced below. Obviously, the drawings described below only involve some embodiments of this utility model, and are not intended to limit this utility model.

[0020] Figure 1 This is a front view schematic diagram of a small end device for a high-speed, high-power diesel engine connecting rod according to an embodiment of the present invention;

[0021] Figure 2 This is a side sectional view of 1;

[0022] Figure 3a This is a schematic diagram of the oil line in the oil tank according to an embodiment of the present invention;

[0023] Figure 3b yes Figure 3a BB-direction sectional view;

[0024] Figure 3c yes Figure 3b Sectional view along axis AA;

[0025] Figure 4 yes Figure 2 A magnified view of part of I. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the described embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0027] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains. The terms “first,” “second,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an” or “a” and similar terms do not indicate a limitation of quantity, but rather indicate the presence of at least one.

[0028] Figure 1 This is a front view schematic diagram of a small end device for a high-speed, high-power diesel engine connecting rod according to an embodiment of the present invention; Figure 2 This is a side sectional view of 1.

[0029] like Figure 1 and Figure 2 As shown, the connecting rod small end device for high-speed, high-power diesel engines includes: body 1, bushing 2, small end oil inlet structure, oil line 4, and oil sump 5.

[0030] The main body 1 is the small end of the connecting rod used to connect the piston pin. It forms a hinge connection with the piston through the piston pin and bears the alternating load of reciprocating motion when the engine is working. The main body 1 is provided with a bottom hole for placing the piston pin.

[0031] A bushing 2 is installed inside the bottom hole. After the bushing 2 is inserted into the bottom hole of the connecting rod small end body 1, it slides and connects with the piston pin.

[0032] The small-head oil inlet structure has an oil hole 3 connected to the side wall of the body 1 and the bushing 2 for connecting lubricating oil.

[0033] Figure 3a This is a schematic diagram of the oil line in the oil tank according to an embodiment of the present invention; Figure 3b yes Figure 3a BB-direction sectional view; Figure 3c yes Figure 3b A sectional view along line AA.

[0034] like Figures 3a to 3c As shown, an oil line 4 communicating with an oil hole 3 and an oil pool 5 communicating with the oil line 4 are provided on the side wall of the bushing 2. The width of the oil pool 5 is greater than the width of the oil line 4.

[0035] The lubricating oil is introduced through the oil hole 3 of the small-end oil inlet structure and can be temporarily stored in the oil line 4 and oil sump 5 to ensure long-term and stable lubrication between the piston pin and the small end of the connecting rod.

[0036] According to one or more embodiments of the present invention, the width of the oil line 4 perpendicular to the direction of lubricating oil flow is greater than the diameter of the oil hole 3, so as to facilitate the entry of lubricating oil.

[0037] According to one or more embodiments of the present invention, one end of the oil line 4 is connected to the oil hole 3, and the other end is connected to the oil tank 5.

[0038] According to one or more embodiments of this utility model, two oil holes 3, two oil lines 4, and two oil pools 5 are provided.

[0039] According to one or more embodiments of the present invention, lubricating oil enters the oil line 4 and oil sump 5 through the oil hole 3 of the body 1 and the oil hole 3 of the bushing 2. The inner walls of the two ends of the bushing 2 in the axial direction are expanded outward with a 3-degree chamfer to allow more lubricating oil to be stored in the bushing 2 holes, thereby enhancing the friction reduction, lubrication and cooling capabilities of the bushing 2 and the piston pin.

[0040] According to one or more embodiments of the present invention, the bushing 2 and the bottom hole of the body 1 are subjected to an interference fit.

[0041] According to one or more embodiments of the present invention, the interference fit between the bushing 2 and the bottom hole of the body 1 is set to 0.106-0.132mm, which is used to strengthen the holding force between the small end bushing 2 and the bottom hole, improve the reliability of the assembly of the small end bushing 2 and the bottom hole, and make it difficult for loosening, rotation or falling off to occur.

[0042] Figure 4 yes Figure 2 A magnified view of part of I.

[0043] like Figure 4 As shown, the axial profile of the inner wall of bushing 2 is designed into three segments, including: an inclined segment 6 at angle a, a straight segment 7, and an inclined segment 8 at angle b, which are arranged in sequence to ensure that the bushing 2 hole and the piston pin maintain a relatively uniform gap during actual operation, thereby making it easier to form a uniform and stable lubricating oil film and ensuring the reliability of lubrication of the bushing 2 hole-piston pin friction pair. Angles a and b are not greater than 3°.

[0044] According to one or more embodiments of the present invention, the bushing 2 is provided with a 4×3° chamfer at both ends to make it easier for more lubricating oil to enter the bushing 2 from both ends of the bushing 2 hole.

[0045] According to one or more embodiments of the present invention, the surface finish of the oil hole 3 of the body 1 is set to Ra1.6, and the transition point with the straight hole is rounded by R2, so as to allow the lubricating oil to enter the bushing 2 more quickly and smoothly through the straight hole, and to provide timely lubrication for the friction between the oil hole 3 of the bushing 2 and the piston pin.

[0046] According to one or more embodiments of the present invention, the bushing 2 is made of copper alloy.

[0047] The connecting rod small end device for high-speed, high-power diesel engines according to this utility model improves the connecting rod small end structure by setting a small end oil inlet structure, oil line, and oil sump, thereby increasing the lubrication stability of the connecting rod small end. After whole-machine testing and verification, it solves the problems of connecting rod small end bushing rotation, burning, abnormal wear, and loosening in this type of diesel engine, and can improve the stability and reliability of the diesel engine.

[0048] The above description is merely an exemplary embodiment of the present utility model and is not intended to limit the scope of protection of the present utility model. The scope of protection of the present utility model is determined by the appended claims.

Claims

1. A connecting rod small end device for a high-speed, high-power diesel engine, characterized in that, include: The body is a connecting rod small end for connecting the piston pin, which forms a hinge connection with the piston pin and bears the alternating load of reciprocating motion when the engine is working. The body is provided with a bottom hole for placing the piston pin. A bushing is provided in the bottom hole, and the bushing is inserted into the bottom hole of the connecting rod small end body and then slidably connected to the piston pin. The small-head oil inlet structure has interconnected oil holes on the side walls of the body and the bushing for connecting lubricating oil. An oil line and an oil sump are provided on the side wall of the bushing, with an oil line communicating with an oil hole and an oil sump connected to the oil line. The width of the oil sump is greater than the width of the oil line. The lubricating oil is introduced through the oil hole of the small-end oil inlet structure and can be temporarily stored in the oil line and oil sump to ensure long-term and stable lubrication between the piston pin and the small end of the connecting rod.

2. The connecting rod small end device for high-speed, high-power diesel engines as described in claim 1, characterized in that, The width of the oil line perpendicular to the direction of lubricating oil flow is greater than the diameter of the oil hole to facilitate the entry of lubricating oil.

3. The connecting rod small end device for high-speed, high-power diesel engines as described in claim 1, characterized in that, One end of the oil line is connected to an oil hole, and the other end is connected to an oil tank.

4. The connecting rod small end device for high-speed, high-power diesel engines as described in claim 1, characterized in that, Two oil holes, two oil lines, and two oil sumps are provided.

5. The connecting rod small end device for a high-speed, high-power diesel engine as described in claim 1, characterized in that, Lubricating oil enters the oil line and oil sump through the oil holes in the main body and the oil holes in the bushing. The inner walls of the two ends of the bushing in the axial direction are widened by a 3-degree chamfer to allow more lubricating oil to be stored in the bushing holes, thereby enhancing the friction reduction, lubrication and cooling capabilities of the bushing and piston pin.

6. The connecting rod small end device for a high-speed, high-power diesel engine as described in claim 1, characterized in that, The bushing and the bottom hole of the body are fitted with an interference fit.

7. The connecting rod small end device for a high-speed, high-power diesel engine as described in claim 6, characterized in that, The interference fit between the bushing and the bottom hole of the body is set to 0.106-0.132mm, which is used to strengthen the holding force between the small end bushing and the bottom hole, improve the reliability of the assembly of the small end bushing and the bottom hole, and make it difficult for loosening, rotation, or falling off to occur.

8. The connecting rod small end device for a high-speed, high-power diesel engine as described in claim 1, characterized in that, The axial profile of the inner wall of the bushing is designed in three sections, including: an inclined section at angle a, a straight section, and an inclined section at angle b, which are arranged in sequence. This is to ensure that the bushing hole and the piston pin maintain a relatively uniform gap during actual operation, so as to more easily form a uniform and stable lubricating oil film and ensure the reliability of lubrication of the bushing hole-piston pin friction pair. The angles a and b are not greater than 3°.

9. The connecting rod small end device for a high-speed, high-power diesel engine as described in claim 1, characterized in that, The bushing has a 4×3° chamfer at both ends to make it easier for more lubricating oil to enter the bushing from both ends of the bushing hole.

10. The connecting rod small end device for a high-speed, high-power diesel engine as described in claim 1, characterized in that, The surface finish of the oil hole conical surface of the body is set to Ra1.6, and the transition point with the straight hole is rounded by R2. This is to allow the lubricating oil to enter the bushing more quickly and smoothly through the straight hole, and to provide timely lubrication for the friction between the bushing oil hole and the piston pin.

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