Lubricating device for piston connecting rod of engine

Abstract

The utility model relates to the technical field of engine pistons, and discloses an engine piston connecting rod lubricating device which comprises a piston, a connecting rod, an air cylinder and a crankshaft, the piston reciprocates in the air cylinder, the connecting rod is connected with the piston, and the connecting rod drives the crankshaft to rotate. And a rebounding structure for rebounding lubricating oil to the inner wall of the air cylinder is arranged on a rod body of the connecting rod. The lubricating device has the remarkable advantages of simple structure, low cost, low oil consumption, long maintenance period, good lubricating effect and the like.

Description

Technical Field

[0001] This utility model relates to the field of engine piston technology, specifically to an engine piston connecting rod lubrication device. Background Technology

[0002] Lubrication between the piston and cylinder wall is a crucial part of the operation of an internal combustion engine. Good lubrication reduces friction and wear, improving the engine's efficiency and lifespan. Engine oil is typically used as a lubricant in internal combustion engines. When the engine is running, the oil rings on the piston and the movement of the crankshaft and connecting rod splash lubricating oil between the piston and cylinder wall, forming a lubricating film. This film reduces direct contact and friction, thus protecting the piston and cylinder wall.

[0003] Chinese patent document CN108194160A discloses an oil-dispensing lubrication mechanism in an engine cylinder, including a piston cylinder and an inner cylinder. The piston cylinder and the inner cylinder are connected. A piston is located inside the piston cylinder, and a connecting rod and a crankshaft are located in the inner cylinder. The connecting rod includes a shaft end and a plug end. The shaft end is connected to the crankshaft, and the plug end is connected to the piston. The inner cylinder is filled with lubricating oil. An oil-dispensing component is located at the shaft end of the connecting rod, facing below the lubricating oil surface. The oil-dispensing component is fixed to the surface of the connecting rod at the shaft end. The oil-dispensing component rotates and swings with the shaft end of the connecting rod, moving below the lubricating oil surface to dispense the lubricating oil. A splashing cavity for lubricating oil is formed between the inner wall of the piston cylinder and the inner cylinder wall. The lubricating oil splashes into the splashing cavity as the oil-dispensing component moves. The above-mentioned document relies on uncertain and irregular lubricating oil splashing, resulting in poor lubrication effect and uneven oil supply between the piston and the cylinder.

[0004] Chinese patent document CN104791069B discloses a connecting rod lubricating oil delivery structure for a diesel engine. The lubricating oil cools the piston of the diesel engine. The piston has an internal cooling oil passage. Two oil inlets communicating with the internal cooling oil passage are symmetrically arranged on the top wall of the piston cavity. The piston is hinged to the small end of the connecting rod, which is located in the piston cavity. The top of the small end of the connecting rod is provided with two asymmetrical oil spray holes. At least one oil spray hole is aligned with the oil inlet during the entire stroke of the piston after top dead center.

[0005] Chinese patent document CN104791069B optimizes the cooling ratio through asymmetric upper oil spray holes, but requires the machining of complex oil passages at the small end of the connecting rod, resulting in high process costs. Summary of the Invention

[0006] This utility model provides an engine piston connecting rod lubrication device with simple structure, good lubrication effect and low manufacturing cost. It includes a piston, connecting rod, cylinder and crankshaft. The piston reciprocates in the cylinder. The connecting rod connects to the piston and drives the crankshaft to rotate. The characteristic feature is that the connecting rod is provided with a rebound structure on the rod body to rebound the lubricating oil to the inner wall of the cylinder.

[0007] Preferably, the rebound structure is inclinedly disposed on the rod body of the connecting rod.

[0008] To ensure precise lubrication of the cylinder inner wall, the angle α formed by the rebound structure and the connecting rod body must satisfy the following relationship:

[0009]

[0010] Where: K is the motion direction compensation coefficient, and the main propulsion side... =0.7-0.9, secondary thrust side L represents the effective length of the rebound structure. This refers to the crankshaft rotation angle; This represents the maximum swing speed of the connecting rod; This is the maximum offset angle between the connecting rod and the axis. ρ is the average mass of the oil splash plate; g is the acceleration due to gravity; The angle between the cylinder axis and the direction of gravity; The viscous resistance correction factor is 0.9-1.5; The dynamic viscosity of the lubricating oil; This is the maximum linear velocity of the piston; To correct the angle of the motion trajectory, the main push side 5°-8°, secondary thrust side 10°-15°.

[0011] Furthermore, the rebound structure employs an oil splash plate or an oil splash ring.

[0012] To improve the lubricating oil rebound effect and simplify the structure, the oil splash plates are arranged on both sides of the connecting rod body in the direction of movement; several main push side oil splash plates are arranged along the main push side of the connecting rod body, and several secondary push side oil splash plates are arranged along the secondary push side of the connecting rod body.

[0013] To avoid introducing additional vibrations due to the oil splash plate, the mass distribution of the oil splash plate should satisfy the following relationship:

[0014] To achieve optimal lubrication, the clearance between the free ends of the main thrust side splash plate and the auxiliary thrust side splash plate and the inner wall of the cylinder must meet the following requirements:

[0015]

[0016] Where K is the material thermal expansion coefficient correction factor (0.8-1.2 for metals, 1.5-2.0 for composite materials), μ is the dynamic viscosity of engine oil, ω is the maximum angular velocity of the connecting rod, and P is the in-cylinder combustion pressure.

[0017] To facilitate oil guidance while reducing turbulence, the free end of the rebound structure is provided with an arc-shaped oil guide section, the radius of curvature of which is the same as the radius of the cylinder inner wall.

[0018] Preferably, the rebound structures are distributed at intervals along the axial direction of the connecting rod, and the number of the spaced rebound structures is 1-4 pieces.

[0019] Preferably, the rebound structure is a split-type kit, which is fixedly connected to the original connecting rod by high-strength adhesive or riveting.

[0020] This utility model has the following beneficial effects:

[0021] 1. This utility model has a simple overall structure and low manufacturing cost. It eliminates the need for additional oil inlet / outlet channels; simply adding a structure for rebounding lubricating oil to the connecting rod improves lubrication. The manufacturing cost of the oil splash plate or oil splash ring is far lower than that of the oil inlet / outlet channels. Simulation of the oil lubrication process was conducted, and the number of oil particles on the cylinder inner wall within 0.5 seconds was statistically analyzed. Figure 4 The results showed that adding the oil splash plate increased the number of oil particles on the cylinder wall by 35%. Bench tests showed that oil consumption was reduced by 22% compared to the traditional structure, and the maintenance cycle was extended by 26%.

[0022] 2. This utility model precisely lubricates the inner wall of the cylinder. By optimizing the mathematical relationship between its tilt angle and motion parameters, it can precisely control the direction and coverage of lubricating oil splash, making the oil film distribution on the inner wall of the cylinder uniform and effectively reducing the risk of cylinder scoring caused by local dry friction. Attached Figure Description

[0023] Figure 1 Schematic diagram of the cross-section of the engine piston connecting rod lubrication device;

[0024] Figure 2 : A schematic diagram of the connecting rod in this embodiment

[0025] Figure 3 A schematic diagram of the movement of oil particles in the engine piston connecting rod lubrication system;

[0026] Figure 4 Comparison chart of oil particle count. Detailed Implementation

[0027] The following detailed description illustrates the specific implementation method:

[0028] The reference numerals in the accompanying drawings include: piston 1, connecting rod 2, cylinder 3, crankshaft 4, crankcase 5, oil splash plate 6, main thrust side oil splash plate 6a, auxiliary thrust side oil splash plate 6b, and free end 7.

[0029] Example 1

[0030] like Figure 1-4 As shown, an engine piston connecting rod lubrication device includes a piston 1, a connecting rod 2, a cylinder 3, and a crankshaft 4. The piston 1 reciprocates within the cylinder 3. The connecting rod 2 connects to the piston 1 and drives the crankshaft 4 to rotate. The piston 1, connecting rod 2, cylinder 3, and crankshaft 4 are all housed within a crankcase 5. The connecting rod 2 has an oil splash plate 6 on its shaft that reflects lubricating oil onto the inner wall of the cylinder 3. Alternatively, an oil splash ring can also be used.

[0031] The oil splash plate 6 is disposed on both sides of the movement direction of the connecting rod 2; three main push side oil splash plates 6a are disposed along the main push side of the connecting rod 2, and three secondary push side oil splash plates 6b are disposed along the secondary push side of the connecting rod 2. The main push side oil splash plates 6a and the secondary push side oil splash plates 6b are disposed obliquely on the connecting rod 2; the oil splash ring does not need to be distinguished.

[0032] The angle α formed by the main thrust side splash plate 6a and the auxiliary thrust side splash plate 6b with the rod body of the connecting rod 2 must satisfy the following relationship:

[0033]

[0034] Take the angle between the engine cylinder axis and the direction of gravity. =135°, maximum crankshaft offset angle =18°, maximum angular velocity of link 2 =116 rad / s, maximum linear velocity of piston 1 =11.796m / s; Average effective length L1 of the main thruster side splash plate 6a is 0.02m; Average effective length L2 of the auxiliary thruster side splash plate 6b is 0.025m; Masses of the three splash plates on the main thruster side 6a are 0.45kg, 0.31kg, and 0.25kg respectively, and masses of the three splash plates on the auxiliary thruster side 6b are 0.35kg, 0.31kg, and 0.25kg respectively; The dynamic viscosity of the lubricating oil is taken as 4mPa. s, Take 135°.

[0035] Mainly recommends side splash guard 6a installation angle for:

[0036]

[0037] in =0.7-0.9, =0.9-1.5, =5°-8°, with Take 0.8, C takes 1.2, Taking 7° as an example for calculation, to ensure that the angle is small so as to adjust the lubricating oil splash angle.

[0038] Auxiliary thruster side splash plate 6b installation angle for:

[0039]

[0040] in =1.1-1.3, =0.9-1.5, =10°-14°, with Take 1.2, C takes 1.2, Taking 12° as an example, the calculation is to ensure that the auxiliary thrust side splash plate 6b moves the lubricating oil as much as possible.

[0041] The mass distribution of the main thruster side splash plate 6a and the auxiliary thruster side splash plate 6b should satisfy the following relationship:

[0042] The mass distribution of the oil splash plates on both sides meets the dynamic balance requirements, so the design parameters are reasonable.

[0043] The clearance between the free ends 7 of the main thrust side splash plate 6a and the auxiliary thrust side splash plate 6b and the inner wall of the cylinder 3 must meet the following requirements:

[0044]

[0045] Where K is the material thermal expansion coefficient correction factor (0.8-1.2 for metals, 1.5-2.0 for composite materials), taken as 0.8; μ is the dynamic viscosity of the engine oil; ω is the maximum angular velocity of connecting rod 2; P is the in-cylinder combustion pressure, taken as 4 MPa; the design value d is taken as 2.9 mm, which meets the actual engineering requirements (0.5). 3mm).

[0046] The free ends 7 of the main thrust side splash plate 6a and the auxiliary thrust side splash plate 6b are provided with arc-shaped oil guides, and the radius of curvature of the arc-shaped oil guides is the same as the radius of the inner wall of the cylinder 3.

[0047] This utility model can be adapted to existing production lines in the following ways:

[0048] Metal connecting rod 2: The oil splash plate 6 is formed in situ using laser cladding additive manufacturing process, without the need to modify the connecting rod 2 blank;

[0049] Powder metallurgy connecting rod 2: The oil splash plate 6-cavity is directly designed in the mold to achieve net forming process;

[0050] The main thrust side splash plate 6a and the auxiliary thrust side splash plate 6b are separate splash plate 6 kits, which are fixedly connected to the original connecting rod 2 by high-strength adhesive or riveting.

[0051] The number of oil particles on the inner wall of cylinder 3 within 0.5 seconds was calculated using a simulation model, and a time / cumulative particle diagram was plotted. (See [link to relevant documentation]). Figure 4 .

[0052] Example 2

[0053] The difference between this embodiment and Embodiment 1 lies in the different angles formed between the main thrust side splash plate 6a and the auxiliary thrust side splash plate 6b and the connecting rod 2. In an engine piston connecting rod lubrication device, the angle α formed by the main thrust side splash plate 6a and the auxiliary thrust side splash plate 6b and the rod body of the connecting rod 2 must satisfy the following relationship:

[0054]

[0055] Take the angle between the engine cylinder axis and the direction of gravity. =135°, maximum crankshaft offset angle =18°, maximum angular velocity of link 2 =116 rad / s, maximum linear velocity of piston 1 =11.796m / s; average effective length L1 of the main thruster side splash plate 6a is 0.02m; average effective length L2 of the auxiliary thruster side splash plate 6b is 0.025m; the dynamic viscosity of the lubricating oil is taken as 4mPa. s, Take 135°.

[0056] Mainly recommends side splash guard 6a installation angle The minimum is:

[0057]

[0058] in =0.7-0.9, =0.9-1.5, =5°-8°, with Take 0.7, C takes 1.5, Taking 5° as an example, the installation angle of the main pusher side splash plate 6a is obtained. The minimum is 32°.

[0059] Auxiliary thruster side splash plate 6b installation angle The minimum is:

[0060]

[0061] in =1.1-1.3, =0.9-1.5, =10°-14°, with Take 1.1, C takes 1.5, Taking 10° as an example, the installation angle of the 6b splash plate on the auxiliary thruster side is obtained. The minimum is 60°.

[0062] The verification of the oil splash plate mass distribution and the verification of the clearance from the free end to the cylinder inner wall are the same as in Example 1.

[0063] Example 3

[0064] The difference between this embodiment and Embodiment 1 lies in the different angles formed between the main thrust side splash plate 6a and the auxiliary thrust side splash plate 6b and the connecting rod 2. In an engine piston connecting rod lubrication device, the angle α formed by the main thrust side splash plate 6a and the auxiliary thrust side splash plate 6b and the rod body of the connecting rod 2 must satisfy the following relationship:

[0065]

[0066] Take the angle between the engine cylinder axis and the direction of gravity. =135°, maximum crankshaft offset angle =18°, maximum angular velocity of link 2 =116 rad / s, maximum linear velocity of piston 1 =11.796m / s; average effective length L1 of the main thruster side splash plate 6a is 0.02m; average effective length L2 of the auxiliary thruster side splash plate 6b is 0.025m; the dynamic viscosity of the lubricating oil is taken as 4mPa. s, Take 135°.

[0067] Mainly recommends side splash guard 6a installation angle The maximum is:

[0068]

[0069] in =0.7-0.9, =0.9-1.5, =5°-8°, with Take 0.9, C takes 0.8, Taking 8° as an example, the installation angle of the main pusher side splash plate 6a is obtained. The maximum is 58°.

[0070] Auxiliary thruster side splash plate 6b installation angle The maximum is:

[0071]

[0072] in =1.1-1.3, =0.9-1.5, =10°-14°, with Take 1.3, C takes 0.9, Taking 14° as an example, the installation angle of the auxiliary thruster side splash plate 6b is obtained. The maximum angle is 90°.

[0073] The verification of the oil splash plate mass distribution and the verification of the clearance from the free end to the cylinder inner wall are the same as in Example 1.

[0074] Comparative Example 1

[0075] Based on Example 1, without installing the oil splash plate 6, the number of oil particles on the inner wall of cylinder 3 within 0.5s was calculated using a simulation model, and a time / cumulative particle diagram was plotted. (See Example 1) Figure 4 .

[0076] according to Figure 4 It can be seen that the number of oil particles on the inner wall of the engine piston 1 and connecting rod 2 lubrication device with oil splash plate 6 is higher than that of the engine piston 1 and connecting rod 2 device without oil splash plate 6 within 0.5s. Moreover, at 0.5s, the number of oil particles on the inner wall of the cylinder 3 with oil splash plate 6 installed at the optimal angle is higher than that with oil splash plate 6 installed at the maximum or minimum angle. After installing oil splash plate 6 at the optimal angle, the number of oil particles on the inner wall of the cylinder 3 increased by 35%. It can be seen that Example 1 can significantly increase the number of oil particles on the inner wall, thereby improving the lubrication effect between cylinder 3 and piston 1.

[0077] The above descriptions are merely embodiments of this utility model. Commonly known structures and characteristics are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are knowledgeable of all existing technologies in that field, and possess the ability to apply conventional experimental methods prior to that date. Therefore, those skilled in the art can, based on the guidance provided in this application, improve and implement this solution in conjunction with their own capabilities. Typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of this utility model. These modifications and improvements should also be considered within the scope of protection of this utility model, and will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. An engine piston connecting rod lubrication device, comprising a piston, a connecting rod, a cylinder, and a crankshaft, wherein the piston reciprocates within the cylinder, the connecting rod connects to the piston, and the connecting rod drives the crankshaft to rotate, characterized in that, The connecting rod is equipped with a rebound structure that bounces lubricating oil back onto the cylinder wall.

2. The engine piston connecting rod lubrication device according to claim 1, characterized in that: The rebound structure is inclinedly mounted on the link.

3. The engine piston connecting rod lubrication device according to claim 2, characterized in that: The angle α formed by the rebound structure and the connecting rod body must satisfy the following relationship: Where: K is the motion direction compensation coefficient, and the main propulsion side... =0.7-0.9, secondary thrust side L represents the effective length of the rebound structure. This refers to the crankshaft rotation angle; This represents the maximum swing speed of the connecting rod; This is the maximum offset angle between the connecting rod and the axis. ρ is the average mass of the oil splash plate; g is the acceleration due to gravity; The angle between the cylinder axis and the direction of gravity; The viscous resistance correction factor is 0.9-1.5; The dynamic viscosity of the lubricating oil; This is the maximum linear velocity of the piston; To correct the angle of the motion trajectory, the main push side 5°-8°, secondary thrust side 10°-15°.

4. The engine piston connecting rod lubrication device according to any one of claims 1-3, characterized in that: The rebound structure uses an oil splash plate or an oil splash ring.

5. The engine piston connecting rod lubrication device according to claim 4, characterized in that: The oil splash plates are arranged on both sides of the connecting rod body in the direction of movement; a number of main push side oil splash plates are arranged along the main push side of the connecting rod body, and a number of secondary push side oil splash plates are arranged along the secondary push side of the connecting rod body.

6. The engine piston connecting rod lubrication device according to claim 5, characterized in that: The mass distribution of the oil splash plate should satisfy the following relationship: in: This indicates the mass of a single oil splash plate on each side, in grams. This indicates the distance from the center of mass of the two oil splash plates to the axis of the connecting rod; This represents the sum of the rotational inertia contributions of all the oil splash plates on one side.

7. The engine piston connecting rod lubrication device according to claim 6, characterized in that: The gap between the free end of the oil splash plate and the inner wall of the cylinder must meet the following requirements: Where K is the material thermal expansion coefficient correction factor, μ is the engine oil dynamic viscosity, ω is the connecting rod maximum angular velocity, and P is the in-cylinder combustion pressure.

8. The engine piston connecting rod lubrication device according to any one of claims 5-7, characterized in that: The free end of the rebound structure is provided with an arc-shaped oil guide, and the radius of curvature of the arc-shaped oil guide is the same as the radius of the cylinder inner wall.

9. The engine piston connecting rod lubrication device according to claim 8, characterized in that: The rebound structures are all distributed at intervals along the axial direction of the connecting rod, and the number of the rebound structures distributed at intervals is 1-4 pieces.

10. The engine piston connecting rod lubrication device according to claim 9, characterized in that: The rebound structure adopts a split-type kit, which is fixedly connected to the original connecting rod by high-strength adhesive or riveting.

Images