Microtexture suitable for surface friction reduction of cam tappet

Abstract

The utility model discloses a microtexture suitable for the antifriction of the surface of a cam tappet, which comprises an antifriction texture, the antifriction texture is crescent and is in a pit shape towards the inside of the tappet, and the single antifriction texture is circumferentially arrayed to form an annular microtexture and is arranged on the contact surface of the tappet and a cam; the multiple annular microtextures are arranged at intervals in the radial direction of the tappet surface, and the surface concave textures are in a crescent shape and evenly distributed on the GCr15 steel surface according to a certain rule. The crescent-shaped pit texture is designed, so that when lubricating oil is driven by a surface base body to move in the movement direction, a large area can be generated at the tail of a plane to obtain a high-pressure area and a large pressure peak value, small cavitation is generated at the front end of the texture, and the area of a low-pressure area can be effectively reduced; and certain abrasive dust can be stored, the contact area with a cam can be reduced, and the surface adhesion force can be reduced, so that excellent tribological performance is obtained under the condition of flowing lubrication, and the bearing capacity between friction pairs is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of mechanical manufacturing, and in particular relates to a micro-texture suitable for reducing friction on the surface of a cam tappet. Background Art

[0002] The cam-tappet is a crucial transmission component in an internal combustion engine. It influences the intake and exhaust processes of the engine by controlling the pattern of valve movement, thereby impacting engine performance. The cam-tappet is one of the three major friction components in an internal combustion engine. When operating under heavy load and high speed, heat is generated on the friction pair surface, leading to severe friction and wear, which significantly affects the lifespan and operating accuracy of the internal combustion engine. Because the clearance between friction pairs is very small, typically at the micron level, macroscopic friction and wear theories are not applicable to the close contact between friction pairs.

[0003] With the rapid development of science and technology, significant progress has been made in reducing friction and anti-wear on cam-tappellant surfaces. Currently, the commonly used methods for reducing friction and anti-wear on cam-tappellant surfaces are mainly through lubricants, surface coatings, sandblasting, polishing, plating, etc. However, the lubricant in these methods needs to be replaced regularly, especially in high-temperature or high-pressure environments, where the lubricant may be squeezed out or volatilized, resulting in reduced lubrication effectiveness. At the same time, when the cam-tappellant operates under heavy loads, the contact surfaces generate high temperatures, which reduces the hardness of the tappet surface. Surface coatings and sandblasting, polishing, plating, etc. are expensive to prepare and require specialized equipment and processes. They also place high demands on the process and still have certain defects.

[0004] Therefore, a new solution is needed to solve the above technical problems. Utility Model Content

[0005] To address the aforementioned technical issues, this utility model designs a micro-texture suitable for reducing friction on the surface of cam lifters. By using GCr15, a commonly used material for lifters, as a substrate, a crescent-shaped texture with a specific geometry is created on its surface. This texture not only provides a certain oil film pressure and stores wear debris under oil lubrication conditions, but also reduces contact area with the cam and lowers surface adhesion, resulting in excellent friction and anti-wear properties. This surface modification with excellent friction and anti-wear properties has broad application prospects in lifters, significantly reducing the problem of severe lifter wear and, consequently, reducing their economic costs.

[0006] In order to achieve the above technical effects, the utility model discloses a micro-texture suitable for reducing friction on the surface of a cam tappet, comprising: a friction-reducing texture, wherein the friction-reducing texture is crescent-shaped and presents a pit shape toward the interior of the tappet, and a single friction-reducing texture is circumferentially arrayed into an annular micro-texture and installed on the surface where the tappet and the cam contact; a plurality of annular micro-textures are arranged at intervals along the radial direction of the tappet surface;

[0007] Furthermore, the width of the pits of the anti-friction texture is between 280-350 microns, the depth is between 20-100 microns, and the surface density of the pit texture is 14%;

[0008] Furthermore, the distance between the two pits ranges from 0.5 to 1.18 cm;

[0009] Furthermore, at least three annular micro-textures are arranged at radial intervals along the surface of the tappet.

[0010] Beneficial effects of the utility model:

[0011] This utility model provides a crescent-shaped, friction-reducing texture suitable for the surface of a cam lifter. This texture significantly reduces friction and wear on the lifter surface while maintaining the same operational performance, thereby improving the cam lifter's reliability. Furthermore, the crescent-shaped texture ensures a certain level of oil film pressure during oil-lubricated operation, storing wear debris between the friction pairs while significantly reducing the contact area between the two surfaces, further minimizing the negative effects of friction and wear on the cam lifter surface. This significantly reduces the problem of severe lifter wear, thereby reducing its economic cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the following briefly introduces the drawings required for describing the embodiments.

[0013] Figure 1 This is the outline design drawing of the crescent-shaped textured outer wheel of the utility model.

[0014] Figure 2 This is a microscopic morphology diagram of the crescent-shaped texture in the present invention.

[0015] Figure 3 It is a schematic diagram of the friction pair structure of the clockwise knitting mechanism in the present invention.

[0016] Figure 4 It is a schematic diagram of the friction pair structure of the counterclockwise knitting mechanism rotation motion in the present invention.

[0017] Figure 5 This is a pressure distribution cloud diagram of the clockwise knitting structure in the present invention.

[0018] Figure 6This is a comparison chart of the friction coefficient between the utility model and the prior art;

[0019] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0020] 1-GCr15 steel substrate, 2-pits. DETAILED DESCRIPTION

[0021] The utility model discloses a micro-texture suitable for reducing friction on the surface of a cam tappet, comprising: a friction-reducing texture, wherein the friction-reducing texture is crescent-shaped and presents a concave shape toward the interior of the tappet, and a single friction-reducing texture circumferential array forms an annular micro-texture installed on the contact surface between the tappet and the cam; a plurality of annular micro-textures are arranged at intervals along the radial direction of the tappet surface;

[0022] Example

[0023] like Figure 1-2 As shown, the anti-friction texture is applied to a GCr15 steel substrate 1. The surface of the GCr15 steel substrate 1 is uniformly arranged with a crescent-shaped texture, with each texture maintaining a uniform spacing. The crescent-shaped texture has a depth of 20-100 microns, and the surface density of the pit texture is 14%. Compared with the untextured sample, the friction coefficient of the sample exhibited varying degrees of anti-friction effects. When the texture depth was 20 μm, the friction coefficient decreased by 65.81% and the wear volume decreased by 74.19%. A higher texture density often fails to achieve the desired anti-friction effect. Therefore, to optimize the anti-friction effect, the surface density of the pit texture was controlled at 14%.

[0024] In this embodiment, if Figure 3 and Figure 4 As shown, the crescent-shaped anti-friction texture of the present invention can be applied as a friction surface on a friction pair, with the movement direction being the rotation direction ω. Specifically, the surface of the base body is an annular plane, and a plurality of pit textures are distributed in a circular array; wherein the anti-friction texture is evenly spaced along the movement direction of the base surface to form an annular micro texture; wherein the pit texture is evenly spaced along the radial direction of the surface to form the anti-friction micro texture described in the present invention, and at the same time, as Figure 3 and Figure 4 Said anti-friction texture may be arranged in a clockwise direction or in a counterclockwise direction;

[0025] In this embodiment, if Figure 5 and Figure 6As shown, the crescent-shaped pit texture designed in the present invention enables the lubricating oil to move on the surface along the direction of movement. On the one hand, it can generate a large area of ​​high-pressure area and a large oil film pressure peak at the tail of the texture. On the other hand, it can generate a very small gap at the entrance of the texture, which can effectively reduce the area of ​​the low-pressure area. And when moving on the surface along the direction of movement, it can absorb small wear debris to avoid abrasive wear. These three reasons enable the present invention to obtain excellent tribological properties under the conditions of fluid lubrication, improve the bearing capacity between the friction pairs, and at the same time, Figure 6 As shown, compared to a substrate without microtexture, the crescent-shaped texture described in the present invention significantly reduces the friction coefficient of the substrate surface. This ensures the same operating performance of the cam lifter while significantly reducing friction and wear on the lifter surface, improving the reliability of the cam lifter. This can significantly reduce the problem of severe lifter wear and, in turn, reduce its economic costs.

[0026] In this example, the laser parameters for texture preparation were an output power of 3 W, a wavelength of 335 nm, a pulsed laser frequency of 30 kHz, and a pulse duration of 25 microseconds. The laser wavelength was 355 nm, the laser flux during texturing was 1.25 J / cm², and the laser processing depth was 10 μm per laser run.

[0027] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all details in detail, nor do they limit the present invention to only the specific implementation methods described.

Claims

1. A micro-texture suitable for reducing friction on the surface of a cam tappet, characterized in that: include: The anti-friction texture is crescent-shaped and presents a concave shape toward the interior of the tappet, and a single anti-friction texture circumferential array forms an annular micro-texture and is installed on the contact surface between the tappet and the cam; A plurality of annular micro-textures are arranged at intervals along the radial direction of the tappet surface.

2. The micro-texture for reducing friction on the surface of a cam tappet according to claim 1, characterized in that: The width of the pits of the anti-friction texture is between 280-350 microns, the depth is between 20-100 microns, and the surface density of the pit texture is 14%.

3. The micro-texture for reducing friction on the surface of a cam tappet according to claim 1, characterized in that: The distance between the two pits is between 0.5-1.18 cm.

4. The micro-texture for reducing friction on the surface of a cam tappet according to claim 1, characterized in that: At least three annular micro-textures are arranged at intervals along the radial direction of the tappet surface.

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