Preparation method of self-lubricating bearing comprising mat type net and self-lubricating bearing

Abstract

The invention relates to a preparation method of a self-lubricating bearing comprising a mat-shaped net and the self-lubricating bearing, and the preparation method comprises the following steps: providing a metal net which is the mat-shaped net; providing a polymer material; providing a substrate; heating the base plate and laying the composite board on the base plate so as to enable the high polymer material layer to be adhered to the base plate; the high polymer material layer on the other side of the substrate is cut, so that part of the warps are exposed out of the high polymer material layer, and the exposed part of the warps accounts for 10-40% of the total area to form a bearing blank; the bearing blank is rolled to form the self-lubricating bearing, the weft yarns are parallel to the axial direction of the self-lubricating bearing, and the warp yarns are perpendicular to the axial direction of the self-lubricating bearing. According to the self-lubricating bearing prepared by the preparation method, the radial strength of the high polymer material layer can be ensured, meanwhile, the requirement on friction performance is met, and the characteristics of small thickness and high strength are realized.

Description

Technical Field

[0001] The invention belongs to the technical field of sliding bearings, and in particular to a preparation method of a self-lubricating bearing comprising a mat-type net and the self-lubricating bearing. Background Art

[0002] In production, ultra-thin bearings are often used due to limitations in assembly space, weight requirements and other factors. The biggest feature of ultra-thin bearings is that the ratio of the outer diameter of the bearing to the width of the bearing is much larger than that of ordinary bearings. Some bearings can even have a ratio of more than 30. In other words, they are "thin". They are widely used in many fields such as reducers, car seats and hinges. Therefore, they also have some built-in sealing structures to protect the bearings and prevent external fluids and impurities from entering the bearings and causing or aggravating structural damage. However, although thin bearings can meet many special requirements in terms of size and space occupied, they are also accompanied by problems such as insufficient strength. Moreover, defects such as easy damage to the sealing structure on the bearings are also common.

[0003] The existing self-lubricating bearings are generally made of three-layer composite bearings, with a layer of polymer material melted on the green surface, a tin bronze alloy layer in the middle layer, and a substrate at the bottom. In order to ensure strength, the thickness of the bearing is very thick, at least 5mm to ensure that the layers do not peel off, so as to ensure the strength of the bearing in the axial and radial directions and avoid damage during use. However, such a thickness is unacceptable for some special occasions because it takes up too much space. Summary of the invention

[0004] In view of this, the present invention provides a method for preparing a self-lubricating bearing comprising a mat-type mesh and a self-lubricating bearing. The self-lubricating bearing prepared by this method can ensure both axial strength and radial strength while meeting the requirement of a low friction coefficient, i.e., it has a strong load-bearing capacity, and can also solve the problem of thickness, thereby meeting actual needs.

[0005] A method for preparing a self-lubricating bearing comprising a mat-type net comprises the following steps: STEP 101: Provide a metal mesh, the metal mesh is a mat-shaped mesh, which includes a plurality of wefts parallel to each other, and a plurality of warp wires wound on the plurality of wefts, the diameter of the wefts is greater than the diameter of the warp wires so that the warp wires are not deformed when wound on the wefts, the warp wires are made of tin bronze alloy, the porosity of the metal mesh is controlled between 60% and 90%, and the weft wires and the warp wires are sintered together; STEP 102: providing a polymer material, injecting the polymer material onto the metal mesh and allowing the metal mesh to be submerged in the polymer material to form a composite plate; STEP 103: Provide a substrate; STEP 104: heating the substrate and laying the composite plate on the substrate so that the polymer material layer is bonded to the substrate; STEP 105: Cutting the polymer material layer on the other side of the substrate so that part of the warp yarn is exposed from the polymer material layer, and the exposed part of the warp yarn accounts for 10-40% of the total area to form a bearing blank; STEP 106: Roll the bearing blank to make a self-lubricating bearing, wherein the weft wires are parallel to the axial direction of the self-lubricating bearing, and the warp wires are perpendicular to the axial direction of the self-lubricating bearing.

[0006] Furthermore, the weft wire is made of one of carbon steel, manganese steel and titanium steel.

[0007] Furthermore, the tin bronze alloy is one of CuSn10, CuSn13, and CuSn8Zn3.

[0008] Furthermore, the mat-type net is one of a plain weave type, a twill weave type, and a double-filament Dutch weave type.

[0009] Furthermore, the polymer material includes one or more of polyaryletherketone, modified polyetheretherketone, polyamide-imide, modified polyphenylene sulfide, polyvinylidene fluoride, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, polycaprolactam, and ultra-high molecular weight polyethylene.

[0010] Furthermore, the thickness of the metal mesh is 0.4-2 mm.

[0011] Furthermore, the thickness of the substrate is less than 1 mm.

[0012] Furthermore, in STEP 105, the exposed tin-bronze alloy layer accounts for 10-40% of the total area and is complementary to the porosity of the metal mesh.

[0013] Furthermore, the temperature at which the substrate is heated should be able to melt the corresponding polymer material.

[0014] Furthermore, in STEP 104, after the composite sheet is bonded to the substrate by heating, the substrate and the composite sheet are rolled.

[0015] Compared with the prior art, the preparation method of the self-lubricating bearing including the mat-type mesh provided by the present invention uses the metal mesh, and further uses the mat-type mesh, which improves and ensures the strength of the bearing while meeting the self-lubricating performance. At the same time, due to the presence of the metal mesh, the thickness of the self-lubricating bearing can be minimized, thereby meeting the wall thickness requirement. Specifically, the mat-type mesh weft is parallel to the axial direction of the bearing, which can ensure the axial strength of the lubricating material layer, the warp is perpendicular to the axial direction of the bearing and the warp is made of tin bronze alloy, and 10% to 40% of the tin bronze alloy is exposed to the polymer material layer, thereby ensuring the radial strength of the polymer material layer, while meeting the friction performance requirements, and then under the condition of meeting the strength requirements, the total thickness of the substrate and the polymer material can be designed to be very thin, achieving the characteristics of thin thickness and high strength. At the same time, in the above steps, a metal skeleton is formed by the metal mesh, and the polymer material is evenly distributed between the skeletons, thereby improving the strength of the bearing material while ensuring the wear resistance of the bearing. DETAILED DESCRIPTION

[0016] The specific embodiments of the present invention are further described in detail below. It should be understood that the description of the embodiments of the present invention herein is not intended to limit the protection scope of the present invention.

[0017] The present invention provides a method for preparing a self-lubricating bearing comprising a mat-type net, which comprises the following steps: STEP 101: Provide a metal mesh, the metal mesh is a mat-shaped mesh, which includes a plurality of wefts parallel to each other, and a plurality of warp wires wound on the plurality of wefts, the diameter of the wefts is greater than the diameter of the warp wires so that the warp wires are not deformed when wound on the wefts, the warp wires are made of tin bronze alloy, the porosity of the metal mesh is controlled between 60% and 90%, and the weft wires and the warp wires are sintered together; STEP 102: providing a polymer material, injecting the polymer material onto the metal mesh and allowing the metal mesh to be submerged in the polymer material to form a composite plate; STEP 103: Provide a substrate; STEP 104: heating the substrate and laying the composite plate on the substrate so that the polymer material layer is bonded to the substrate; STEP 105: Cutting the polymer material layer on the other side of the substrate so that part of the warp yarn is exposed from the polymer material layer, and the exposed part of the warp yarn accounts for 10-20% of the total area to form a bearing blank; STEP 106: Roll the bearing blank to make a self-lubricating bearing, wherein the weft wires are parallel to the axial direction of the self-lubricating bearing, and the warp wires are perpendicular to the axial direction of the self-lubricating bearing.

[0018] In step STEP101, the metal mesh is a mat-type mesh, which is a prior art, and includes a plurality of wefts arranged in parallel to each other, and a plurality of warps wound on the plurality of the wefts. The mat-type mesh has many types, such as plain weave, twill weave, double-wire Dutch weave, etc. In the present embodiment, the metal mesh is a plain weave mat-type mesh, and each of the warps passes through a plurality of parallel wefts, and two adjacent warps pass through the wefts in an interlaced manner. For twill weave and double-wire Dutch weave, etc., their structures and winding methods are also a prior art, and will not be described one by one here. The diameter of the weft in the metal mesh is greater than the diameter of the warp, and the degree to which the diameter of the weft is greater than the diameter of the warp should be such that the weft will not be deformed when the warp is wound, so as to prevent the weft from being cut during the subsequent cutting process, and also maintain the strength of the weft. The warp wire should have self-lubricating properties to provide self-lubricating ability and also have a certain strength, so it is made of tin bronze alloy material, and the tin bronze alloy can be one of CuSn10, CuSn13, and CuSn8Zn3. The weft wire is used to provide sufficient strength for the self-lubricating bearing, so the weft wire can be made of high-strength materials, such as carbon steel, manganese steel, titanium steel, etc. Of course, it is understandable that for some bearings that need to be flanging, it is necessary to use materials suitable for bending, and it is best not to use materials that are not easy to bend, such as manganese steel, because it is easy to break.

[0019] The porosity of the metal mesh is controlled between 60% and 90%. If it is less than 60%, the porosity will be too small. When the polymer material layer is injection molded, the percentage of the polymer material filled into the metal mesh is too small, which reduces the bonding force between the polymer material layer and the pores of the metal mesh. At the same time, if the percentage of the polymer material filled into the pores is too small, the self-lubricating ability of the self-lubricating bearing will be reduced, which is not conducive to ensuring the lubrication performance of the self-lubricating bearing. If the porosity is too large, the strength that the metal mesh can provide for the self-lubricating bearing will be too small, so that the polymer material layer will be crushed when the bearing is used.

[0020] In addition, the thickness of the metal mesh can be set according to actual needs, but for thin and high strength, its thickness should be between 0.4 and 2 mm. In this application, according to different specifications, the thickness of the metal mesh can be one of 0.48 mm, 0.78 mm, and 0.98 mm.

[0021] At the same time, when using the metal mesh, the metal mesh should also be sintered so that the weft and warp are sintered together. Because when the plate-shaped bearing blank is made, it is also necessary to roll it according to the size of the self-lubricating bearing used. In the bending and rolling process, in order to prevent the weft and warp of the metal mesh from being misaligned with each other, resulting in the separation of the metal mesh and the polymer material, the weft and warp need to be sintered together. The sintering temperature is generally between 850-950°C, that is, as long as the warp made of copper alloy can be sintered on the weft made of steel.

[0022] In STEP102, the polymer material includes one or more of polyaryletherketone (PAEK), modified polyetheretherketone (PEEK), polyamide-imide (PAI), modified polyphenylene sulfide (PPS), polyvinylidene fluoride (PVDF), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), polycaprolactam (PA6), and ultra-high molecular weight polyethylene (UHMWPE). The above materials are suitable for injection molding and also have certain self-lubricating properties. The injection molding method and equipment itself should be a prior art and will not be repeated here. In addition, in order to improve the functionality of the polymer material, such as injection moldability, wear resistance, and friction reduction, some other materials such as release agents, molybdenum disulfide, carbon fiber, graphite, etc. will be added. The composite sheet is formed by injecting the polymer material into the metal mesh and submerging or sandwiching the metal mesh in the polymer material. In addition, it should be noted that after the composite sheet is formed, the polymer material layer is 30 to 500um higher than the metal mesh. Of course, it cannot be too thick, otherwise it will be difficult to manufacture and it will be difficult to make the polymer material layer.

[0023] In STEP 103, the substrate may be a plate made of a material such as copper, steel, or alloy, which is a prior art and will not be described in detail herein. The thickness of the substrate may be less than 1 mm.

[0024] In STEP 104, the substrate is heated by heating, and the heating method can be heating in a heating furnace, microwave heating, etc., which is a prior art. The temperature of heating the substrate should be suitable for melting the polymer material, so that the composite sheet is fixedly bonded to the substrate. Of course, it is conceivable that in order to strengthen the bonding strength between the composite sheet and the substrate, the substrate can also be rolled.

[0025] In STEP105, by turning, part of the warp of the metal mesh is exposed from the polymer material layer to form the bearing blank. Specifically, the area of ​​the exposed warp accounts for 10-40% of the total area, which is complementary to the porosity of the metal mesh, that is, if the porosity of the metal mesh is X, then the metal mesh is filled with polymer materials, and after turning layer by layer, the warp will be exposed on the blue surface, and the copper exposure rate after turning is 100-X. The proportion of the area of ​​the exposed warp wire to the total area should be set at 10-40%. If the proportion is too large, the friction performance will decrease, and if the proportion is too small, the load-bearing performance will decrease.

[0026] In STEP106, after the bearing blank is manufactured, the bearing blank is rolled and welded, and then the bearing is interference fit on the outer diameter of the pin shaft, and finally fine processing is performed to make a sliding bearing. In the process of rolling the bearing, the weft wire should be parallel to the axial direction of the self-lubricating bearing, and the warp wire should be perpendicular to the axial direction of the self-lubricating bearing. Because when the bearing is in use, its rotation direction is usually perpendicular to the axial direction of the bearing, so making the warp wire perpendicular to the bearing of the bearing will be more in line with the direction of friction. When the seat recliner bearing is installed, the pressure from other assemblies such as nuts is mostly parallel to the axial direction of the bearing, so the weft wire is parallel to the axial direction of the bearing to increase its axial bearing capacity.

[0027] The self-lubricating bearing including the mat-type mesh prepared by the above-mentioned preparation method comprises a substrate and a self-lubricating layer fixedly arranged on the substrate. The self-lubricating layer comprises a metal mesh and a polymer material layer sealed in the metal mesh. The metal mesh is a mat-type mesh, which comprises a plurality of mutually parallel wefts and a plurality of warps wound on the plurality of the wefts. The diameter of the weft is greater than the diameter of the warp so that the warp does not deform when wound on the weft. The extension method of the weft is parallel to the axial direction of the self-lubricating bearing, and the extension method of the warp is perpendicular to the axial direction of the self-lubricating bearing. The warp is made of tin bronze alloy. The porosity of the metal mesh is controlled between 60% and 90%. The radial free surface of the self-lubricating layer is cut to expose the warp and the exposed part of the warp accounts for 10 to 40% of the total area. Example 1

[0028] STEP 101: Provide a metal mesh, wherein the porosity of the metal mesh is controlled to be about 70%, and the thickness of the metal mesh is 0.48 mm; STEP 102: Provide a polymer material, which is modified polyetheretherketone, and inject it onto the metal mesh so that the metal mesh is submerged in the polymer material to form a composite plate. The total thickness of the polymer material layer is about 0.8 mm to 1.0 mm. STEP 103: Provide a substrate, wherein the substrate is a carbon steel plate with a thickness of 0.5 mm; STEP 104: using a resistance heating furnace, heating the substrate to 380° C., and laying the composite board on the substrate so that the polymer material layer is bonded to the substrate to form a semi-finished board; STEP 105: The semi-finished plate is turned to a thickness of about 0.3 mm. At this time, the green surface shows evenly distributed tin bronze alloy embedded in the polymer material, and the copper exposure rate is about 15% to form a bearing blank. STEP106: Rewind and weld the finished composite sheet into a bushing, and heat-seal the bushing onto the green surface of the pin to form a sliding bearing. Example 2

[0029] STEP 101: Provide a metal mesh, wherein the porosity of the metal mesh is controlled to be about 80%, and the thickness of the metal mesh is 0.98 mm; STEP 102: Provide a polymer material, which is modified polyphenylene sulfide, and inject it onto the metal mesh so that the metal mesh is submerged in the polymer material to form a composite plate. The total thickness of the polymer material layer is about 1.8 mm to 2.0 mm. STEP 103: Provide a substrate, wherein the substrate is a carbon steel plate with a thickness of 0.5 mm; STEP 104: Using a resistance heating furnace, heat the substrate to 290° C., and lay the composite board on the substrate so that the polymer material layer is bonded to the substrate to form a semi-finished board; STEP 105: The semi-finished plate is turned to a thickness of about 0.4 mm. At this time, the green surface shows evenly distributed tin bronze alloy embedded in the polymer material, and the copper exposure rate is about 30% to form a bearing blank. STEP106: Rewind and weld the finished composite sheet into a bushing, and heat-seal the bushing onto the green surface of the pin to form a sliding bearing.

[0030] Comparative Example 1 In this comparative example, the sliding bearing was manufactured using the preparation method disclosed in CN202010699463.7; the metal substrate was a carbon steel plate with a thickness of 0.5 mm; the metal mesh was a single-layer woven copper mesh with a thickness of 0.48 mm; and the thickness of the polymer slurry on the copper mesh was approximately 0.7 mm.

[0031] Comparative Example 2 In this comparative example, a polymer material is directly sintered on a carbon steel substrate, wherein the polymer material is modified polyetheretherketone to form a sliding bearing.

[0032] Inspection and testing The first test item is the compression strength test, that is, the load size when the compression deformation is 0.1%. The higher the load, the better the bearing performance and the higher the fatigue strength. After testing, the unit load of Example 1 is 110MPa, Example 2 is 125MPa, Comparative Example 1 is 83MPa, and Comparative Example 2 is only 60MPa.

[0033] Test item 2 is the friction and wear performance test. The composite finished plate prepared in Example 1-2 and Comparative Example 1-2 is made into samples and subjected to the end face friction performance test. The sample size is 37mm×37mm×δmm (δ is the actual thickness of the plate). Test conditions: load 15 MPa, speed 0.4 m / min, time 3h; lubrication conditions: one-time grease application. Test requirements: friction coefficient ≤0.10, wear amount ≤0.03.

[0034] name Friction coefficient () Wear amount / mm Example 1 (PEEK) 0.064 0.008 Example 2 (PPS) 0.073 0.006 Comparative Example 1 (PTFE) 0.037 0.010 Comparative Example 2 (PEEK) 0.042 0.040 Compared with the prior art, the preparation method of the self-lubricating bearing including the mat-type mesh provided by the present invention uses the metal mesh, and further uses the mat-type mesh, which improves and ensures the strength of the bearing while meeting the self-lubricating performance. At the same time, due to the presence of the metal mesh, the thickness of the self-lubricating bearing can be made thinner, thereby meeting the requirements of modern seats. Specifically, the weft of the mat-type mesh is parallel to the axial direction of the bearing, which can ensure the axial strength of the lubricating material layer, the warp is perpendicular to the axial direction of the bearing and the warp is made of tin bronze alloy, and 10% to 40% of the tin bronze alloy is exposed from the polymer material layer, thereby ensuring the radial strength of the polymer material layer, while meeting the requirements of the automotive seat and hinge for friction performance, and then the total thickness of the substrate and the polymer material can be designed to be very thin under the requirements of its strength, achieving the characteristics of thin thickness and high strength. At the same time, in the above steps, a metal skeleton is formed by the metal mesh, and the polymer material is evenly distributed between the skeletons, thereby improving the strength of the bearing material while ensuring the wear resistance of the bearing.

[0035] The above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modification, equivalent substitution or improvement within the spirit of the present invention is included in the scope of the claims of the present invention.

Claims

1. A method for preparing a self-lubricating bearing comprising a mat-type net, comprising the following steps: STEP 101: Provide a metal mesh, the metal mesh is a mat-shaped mesh, which includes a plurality of wefts parallel to each other, and a plurality of warp wires wound on the plurality of wefts, the diameter of the wefts is greater than the diameter of the warp wires so that the warp wires are not deformed when wound on the wefts, the warp wires are made of tin bronze alloy, the porosity of the metal mesh is controlled between 60% and 90%, and the weft wires and the warp wires are sintered together; STEP 102: providing a polymer material, injecting the polymer material onto the metal mesh and allowing the metal mesh to be submerged in the polymer material to form a composite plate; STEP 103: Provide a substrate; STEP 104: heating the substrate and laying the composite plate on the substrate so that the polymer material layer is bonded to the substrate; STEP 105: Cutting the polymer material layer on the other side of the substrate so that part of the warp yarn is exposed from the polymer material layer, and the exposed part of the warp yarn accounts for 10-40% of the total area to form a bearing blank; STEP 106: Roll the bearing blank to make a self-lubricating bearing, wherein the weft wires are parallel to the axial direction of the self-lubricating bearing, and the warp wires are perpendicular to the axial direction of the self-lubricating bearing.

2. The method for preparing a self-lubricating bearing comprising a mat-type net according to claim 1, characterized in that: The weft wire is made of one of carbon steel, manganese steel and titanium steel.

3. The method for preparing a self-lubricating bearing comprising a mat-type net according to claim 1, characterized in that: The tin bronze alloy is one of CuSn10, CuSn13 and CuSn8Zn3.

4. The method for preparing a self-lubricating bearing comprising a mat-type net according to claim 1, characterized in that: The mat-type net is one of a plain weave type, a twill weave type, and a double-filament Dutch type.

5. The method for preparing a self-lubricating bearing comprising a mat-type net according to claim 1, characterized in that: The polymer material includes one or more of polyaryletherketone, modified polyetheretherketone, polyamide-imide, modified polyphenylene sulfide, polyvinylidene fluoride, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, polycaprolactam, and ultra-high molecular weight polyethylene.

6. The method for preparing a self-lubricating bearing comprising a mat-type net according to claim 1, characterized in that: The thickness of the metal mesh is 0.4-2 mm.

7. The method for preparing a self-lubricating bearing comprising a mat-type net according to claim 1, characterized in that: The thickness of the substrate is less than 1 mm.

8. The method for preparing a self-lubricating bearing comprising a mat-type net according to claim 1, characterized in that: In STEP 105 , the exposed tin-bronze alloy layer accounts for 10 to 40% of the total area and is complementary to the porosity of the metal mesh.

9. The method for preparing a self-lubricating bearing comprising a mat-type net according to claim 1, characterized in that: The temperature at which the substrate is heated should be able to melt the corresponding polymer material.

10. A self-lubricating bearing comprising a mat-type net, characterized in that: The self-lubricating bearing including a mat-type mesh includes a substrate and a self-lubricating layer fixedly arranged on the substrate, the self-lubricating layer includes a metal mesh and a polymer material layer sealed in the metal mesh, the metal mesh is a mat-type mesh, which includes a plurality of mutually parallel wefts and a plurality of warp wires wound on the plurality of wefts, the diameter of the weft is greater than the diameter of the warp so that the warp wires are not deformed when wound on the weft, the extension of the weft is parallel to the axial direction of the self-lubricating bearing, the warp wire is made of tin bronze alloy, the porosity of the metal mesh is between 60% and 90%, and the radial free surface of the self-lubricating layer is cut to expose the warp wires and the exposed portion of the warp wires accounts for 10 to 40% of the total area.