Cutter for cutting polyurethane, polyurethane cutting device and cutting method

Abstract

The invention provides a cutter for cutting polyurethane, a polyurethane cutting device and a cutting method. The cutter for cutting polyurethane comprises a cutter body and a cutting edge, the cutter body is fixedly connected with the cutting edge; the main angle of the cutting edge is 20-32 degrees, and the auxiliary angle of the cutting edge is 40-45 degrees; the cutting edge is made of hard materials with the Rockwell hardness larger than or equal to 25 HRC. The cutter for cutting polyurethane is fixed to the cutter table through the through holes, the high-strength bolts are arranged in the through holes, meanwhile, the fixed pressing plate is arranged to press a polyurethane cylinder integrally formed through pouring for cutting, a polyurethane polishing pad high in thickness precision and small in surface roughness can be obtained, and the cutter is suitable for large-scale application and popularization.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical mechanical polishing processing, and particularly relates to a tool for cutting polyurethane, a polyurethane cutting device and a cutting method. Background Art

[0002] In the manufacture of integrated circuits and other electronic devices on semiconductor wafers, multiple layers of conductive materials, semiconductor materials and dielectric materials are deposited on the wafers, or multiple layers of conductive materials, semiconductor materials and dielectric materials are etched away from the wafers. These thin layers of materials can be deposited by many deposition techniques. Conventional deposition techniques in modern wafer processing include physical vapor deposition, chemical vapor deposition, plasma-enhanced chemical vapor deposition, and electroplating. General etching techniques include wet and dry isotropic and anisotropic etching.

[0003] As materials are etched and deposited in sequence, the surface of the wafer becomes uneven. Since subsequent semiconductor processing requires the wafer to have a flat surface, the wafer needs to be planarized. Planarization can be used to remove unwanted surface topographies and surface defects, such as rough surfaces, agglomerated materials, lattice damage, scratches, contaminated layers or materials.

[0004] Chemical mechanical polishing is one of the semiconductor manufacturing processes. Starting from interlayer insulating films such as oxide films, it has been extended to polysilicon electrodes, tungsten plugs for conduction, and the high performance of STI devices. At the same time, the introduced copper wiring technology is also one of its key technologies. And advanced planarization technologies are also under research and development, but chemical mechanical planarization technology is considered to be the best technology for global planarization. During the polishing process, the polishing pad and the wafer rotate around their respective coaxial centers, and at the same time, the wafer and the polishing layer are in contact. The rotation axis of the wafer is offset from the rotation axis of the polishing pad by a distance greater than the radius of the wafer, so that the rotation of the polishing pad sweeps out an annular polishing track on the polishing layer of the polishing pad, and when the wafer only rotates, the width of the wafer track is equal to the diameter of the wafer. During the polishing process, slurry or other polishing media flow onto the polishing pad and into the gap between the wafer and the polishing layer. Through the chemical and mechanical actions of the polishing layer and the polishing media on the wafer surface, the wafer surface is polished and flattened.

[0005] More and more research has been conducted on the interaction between the polishing layer, the polishing media and the wafer surface during chemical mechanical polishing in an effort to optimize the design of the polishing pad.

[0006] CN203281901U discloses a special slicing tool for a polishing pad, wherein a first rounded corner is provided at the main cutting point, and a second rounded corner is provided at the friction part, and the radius R of the first rounded corner 1 = 3 - 5 mm, and the radius R of the second rounded corner 2= 5 - 8 mm. The main cutting point is arc-shaped and has a surface contact with the elastomer, avoiding the generation of cutting lines on the polishing pad, forming a smooth surface plane for the product, and reducing the rejection rate. The contact position between the friction part and the elastomer is arc-shaped, reducing the friction force at the contact position and minimizing material deformation.

[0007] CN112677065A discloses a processing device and method for a polishing pad and a polishing pad obtained therefrom. The processing device includes a gear-type cutter, which can process the polishing pad through multiple rows of gear cutters, improving the working efficiency of polishing pad groove processing. The polishing pad processing method using the processing device not only solves the problem that the plunge milling cutter cannot perform complete cutting, but also the gear-type cutter is combined with gas cooling, which can greatly reduce the temperature of the polishing pad and the cutter during the processing, avoiding the melting phenomenon of the vertical milling cutter. The polishing pad processed by the processing method can effectively ensure the consistency of the groove width and depth of the product, with a flatness ≤ 0.1 mm and a surface roughness ≤ 6, greatly improving the appearance and quality of the product.

[0008] However, there are currently no very suitable tools and corresponding cutting methods for cutting and processing polyurethane polishing pads with relatively high hardness. Summary of the Invention

[0009] In view of the problems existing in the prior art, the present invention provides a tool for cutting polyurethane, a polyurethane cutting device, and a cutting method. The tool for cutting polyurethane includes a tool body and a cutting edge. The cutting edge has a main angle and a secondary angle within a specific range, and the tool is sharp, capable of well cutting a polyurethane cylinder to obtain a polyurethane polishing pad with high thickness accuracy. The present invention also fixes the tool by setting high-strength bolts in a through hole and provides a fixing pressing plate to reduce the degree of tool displacement and deformation.

[0010] To achieve this purpose, the present invention adopts the following technical solutions:

[0011] In a first aspect, the present invention provides a tool for cutting polyurethane. The tool for cutting polyurethane includes a tool body and a cutting edge; the tool body and the cutting edge are fixedly connected; the main angle of the cutting edge is 20 - 32°, and the secondary angle is 40 - 45°; the material of the cutting edge is selected from hard materials with a Rockwell hardness ≥ 25 HRC.

[0012] In the tool for cutting polyurethane according to the present invention, the main angle of the cutting edge is 20° to 32°, and the secondary angle is 40° to 45°, ensuring that the tool for cutting polyurethane is sharp during use and has a long service life. The main angle and the secondary angle of the cutting edge described in the present invention do not exceed the upper limit angle, otherwise the normal cutting of the polyurethane cylinder cannot be achieved. When the main angle of the cutting edge is less than 20° and the secondary angle is less than 40°, the quality of the polyurethane polishing pad obtained by cutting will be poor, with large thickness accuracy and surface roughness, and the service life of the tool will be shortened, resulting in poor economy.

[0013] The main angle of the cutting edge described in the present invention is 20° to 32°, for example, it can be 20°, 21°, 22°, 23°, 23.5°, 24°, 24.5°, 25°, 25.5°, 26°, 26.5°, 27°, 27.5°, 28°, 28.5°, 29°, 29.5°, 30°, 30.5°, 31°, 31.5°, 32°, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable; the secondary angle is 40° to 45°, for example, it can be 40°, 41°, 42°, 43°, 44°, 44.5° or 45°, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0014] The material of the cutting edge described in the present invention is selected from hard materials with a Rockwell hardness ≥ 25HRC, such as 28HRC, 30HRC, 31HRC, 34HRC, 35HRC, 40HRC, 45HRC, 50HRC, 55HRC, 60HRC, 65HRC, 70HRC, etc., preferably including cemented carbide, such as any one or combination of tungsten-cobalt cemented carbide, tungsten-titanium cemented carbide, tungsten-tantalum cemented carbide, titanium carbide-based cemented carbide, etc., but not limited thereto; it can also be other hard materials with a Rockwell hardness meeting the above indicators, such as high-speed steel, etc.

[0015] Preferably, the purpose of the fixed connection is to firmly fix the cutting edge on the tool body to prevent the cutting edge from loosening and shifting during cutting, resulting in a reduction in the cutting yield and even damage to the product. Those skilled in the art can understand that all methods of fixed connection can be applied to the present invention, and welding is preferably used, such as submerged arc welding or brazing.

[0016] The tool body and the cutting edge of the tool for cutting polyurethane according to the present invention are preferably welded by submerged arc welding or brazing. Compared with argon arc welding, the effect of submerged arc welding or brazing is better, and the service life of the tool is longer.

[0017] Preferably, the length of the tool body is 660 - 1100 mm, for example, it can be 660 mm, 700 mm, 760 mm, 800 mm, 860 mm, 900 mm, 950 mm, 960 mm, 970 mm, 980 mm, 990 mm, 1000 mm or 1100 mm, etc., but not limited to the listed values, and other unlisted values within this range are equally applicable.

[0018] Preferably, the material of the tool body is selected from materials with a Rockwell hardness > 15 HRC, such as 16 HRC, 17 HRC, 18 HRC, 19 HRC, 20 HRC, 21 HRC, 22 HRC, 23 HRC, 24 HRC, 25 HRC, etc. or materials with a higher Rockwell hardness, and preferably includes 45 steel.

[0019] Preferably, the length of the blade is 660 - 1100 mm, for example, it can be 660 mm, 700 mm, 800 mm, 900 mm, 910 mm, 1000 mm or 1100 mm, etc., but not limited to the listed values, and other unlisted values within this range are equally applicable. Generally, the length of the blade is greater than the diameter of the polyurethane cylinder to be cut, so that a polishing pad with the target thickness can be obtained in one cutting operation.

[0020] The blade of the present invention can also be heat-treated by heat treatment processes such as quenching and annealing according to needs. The specific quenching and annealing can completely refer to the prior art, and the present invention has no special limitations.

[0021] In a second aspect, the present invention also provides a polyurethane cutting device, which includes the tool for cutting polyurethane described in the first aspect, a tool table, a pressing plate bracket and a fixed pressing plate;

[0022] The tool for cutting polyurethane is fixed on the tool table through a through hole, and 8.8 - 10.9 grade high-strength bolts are arranged in the through hole;

[0023] The pressing plate bracket is connected to the tool table;

[0024] The fixed pressing plate is fixed on the pressing plate bracket and moves synchronously with the tool table;

[0025] The gap between the blade of the tool for cutting polyurethane and the fixed pressing plate is 1.34 - 1.53 mm.

[0026] The length of the tool body of the present invention is 660 - 1100 mm, the length of the blade is 660 - 1100 mm, and the material of the tool body is a material with an HRC greater than 15, such as including 45 steel. The material of the blade is selected from hard materials with a Rockwell hardness ≥ 25 HRC, and preferably includes tungsten carbide cobalt-based hard alloys or titanium carbide-based hard alloys.

[0027] In the present invention, the length of the tool for cutting polyurethane is relatively long and heavy, making it difficult to fix. Compared with the traditional method of fixing by counterbore, the tool for cutting polyurethane in the present invention is fixed on the tool table through a through hole, and high-strength bolts of grade 8.8-10.9 are arranged in the through hole, which can withstand large torque and shear stress. The through hole can ensure that all bolts are tightly pressed on the tool body, avoiding the problem that in the traditional fixing method, only part of the lower bolt is pressed on the tool body, resulting in deformation of the non-pressed part when stress is applied. The clearance between the cutting edge of the tool for cutting polyurethane and the fixed pressing plate on the tool table is 1.34-1.53 mm, ensuring that when using the tool for cutting polyurethane to cut the cast-in-one polyurethane cylinder to obtain a polyurethane polishing pad, the polyurethane polishing pad has a high thickness accuracy. When the clearance between the cutting edge of the tool for cutting polyurethane and the fixed pressing plate on the tool table is less than 1.34 mm or greater than 1.53 mm, the thickness accuracy of the obtained polyurethane polishing pad will be reduced.

[0028] In the present invention, the clearance between the cutting edge of the tool for cutting polyurethane and the fixed pressing plate pressing on the polyurethane cylinder is 1.34-1.53 mm. For example, it can be 1.34 mm, 1.35 mm, 1.38 mm, 1.4 mm, 1.45 mm, 1.5 mm or 1.53 mm, etc., but is not limited to the listed values. Other unlisted values within this numerical range are equally applicable.

[0029] Preferably, high-strength bolts of grade 8.8-10.9 are arranged in the through hole. For example, it can be grade 8.8, grade 8.9, grade 9, grade 9.5, grade 10, grade 10.5 or grade 10.9, etc., but is not limited to the listed values. Other unlisted values within this numerical range are equally applicable.

[0030] Preferably, the material of the fixed pressing plate includes cast iron after aging treatment, which has good rigidity and high anti-bending and anti-twisting characteristics. Specifically, the cast iron after aging treatment is, for example, cast iron after quenching.

[0031] Those skilled in the art can understand that to ensure smooth cutting, the fixed pressing plate should fully press the polyurethane cylinder, that is, the part of the polyurethane cylinder near the cutting edge should be fully pressed. For this purpose, the length of the fixed pressing plate (i.e., the length along the cutting edge direction) is usually greater than or equal to the diameter of the polyurethane cylinder. The width of the fixed pressing plate has no special limitation, such as 6-12 cm, etc., but is not limited thereto; the weight of the fixed pressing plate is usually not less than 20 kg. At the same time, the surface of the fixed pressing plate is usually relatively flat, so as to tightly press the polyurethane cylinder.

[0032] In a third aspect, the present invention further provides a method for cutting polyurethane. The polyurethane cutting device as described in the second aspect is used to cut a polyurethane cylinder formed by integral casting to obtain a polyurethane polishing pad.

[0033] The polyurethane cutting device of the present invention is used to cut a polyurethane cylinder formed by integral casting. The obtained polyurethane polishing pad has a high thickness accuracy and a small surface roughness. Due to the high thickness accuracy, subsequent processes such as grinding are not required, reducing the process length and the processing cost of the polyurethane polishing pad.

[0034] The polyurethane cylinder of the present invention is integrally cast on a bearing plate, and the bearing plate can be, for example, an iron plate.

[0035] Preferably, the diameter of the polyurethane cylinder is 660 - 1000 mm, and can be, for example, 660 mm, 700 mm, 800 mm, 850 mm, 900 mm, 950 mm, 980 mm or 1000 mm, etc., but is not limited to the listed values. Other unlisted values within this range are equally applicable;

[0036] The height is 6 - 15 cm, and can be, for example, 6 cm, 10 cm, 11 cm, 12 cm, 13 cm, 14 cm or 15 cm, etc., but is not limited to the listed values. Other unlisted values within this range are equally applicable.

[0037] Preferably, when the polyurethane cutting device of the present invention cuts the polyurethane cylinder, the cutting resistance of each piece of the polyurethane cylinder is 40 - 50 tons, and can be, for example, 40 tons, 42 tons, 45 tons, 46 tons, 47 tons, 49 tons or 50 tons, etc., but is not limited to the listed values. Other unlisted values within this range are equally applicable.

[0038] When the polyurethane cutting device of the present invention cuts the polyurethane cylinder, a fixed pressing plate is provided at the top of the polyurethane cylinder, which can offset part of the stress received by the tool during cutting and reduce the degree of tool displacement and deformation.

[0039] Preferably, when cutting the polyurethane cylinder, the straightness of the tool for cutting the polyurethane is -10 - 10 μm, and can be, for example, -10 μm, -8 μm, -5 μm, -3 μm, 0 μm, 1 μm, 5 μm or 10 μm, etc., but is not limited to the listed values. Those skilled in the art can understand that when the straightness of the tool for cutting the polyurethane is 0 μm, it indicates that the cutting direction of the tool during horizontal cutting is always on the same horizontal plane.

[0040] Preferably, the thickness accuracy of the polyurethane polishing pad is -10 to 10 μm. For example, it can be -10 μm, -8 μm, -5 μm, -3 μm, 1 μm, 5 μm, 10 μm, etc., but it is not limited to the listed values. Other unlisted values within this range are also applicable. It can be understood that the smaller the absolute value of the thickness accuracy, the higher the cutting accuracy, that is, the better the flatness of the cut polyurethane polishing pad.

[0041] Preferably, the surface roughness of the polyurethane polishing pad is 2 to 6.5 μm. For example, it can be 2 μm, 2.3 μm, 2.5 μm, 3 μm, 3.5 μm, 4 μm, 4.5 μm, 5 μm, 5.5 μm, 6 μm, etc., preferably 2 to 4 μm, but it is not limited to the listed values. Other unlisted values within this range are also applicable.

[0042] Compared with the prior art, the present invention has at least the following beneficial effects:

[0043] For the polyurethane with relatively large cutting resistance, the present invention adopts a specific tool and a specific fixing method designed to match it, and processes a polyurethane polishing pad with the thickness accuracy meeting the requirements, the surface roughness meeting the requirements, and the thickness within the target range. The subsequent grinding process can be omitted, effectively improving the processing efficiency of the polyurethane polishing pad, shortening the production line length, and being suitable for large-scale popularization and application. Description of the Drawings

[0044] Figure 1 is a schematic structural diagram of the polyurethane cutting device provided by the present invention.

[0045] Figure 2 is a cross-sectional view of the cutting edge of the tool for cutting polyurethane provided by the present invention.

[0046] In the figure: 1 - tool; 101 - cutting edge; 102 - tool body; 2 - high-strength bolt; 3 - tool table; 4 - fixed pressing plate; 5 - polyurethane cylinder; 6 - bearing plate; 7 - main angle; 8 - secondary angle; 9 - through hole. Detailed Embodiments

[0047] The technical solution of the present invention will be further described below in conjunction with the drawings and through specific embodiments.

[0048] The present invention will be further described in detail below. However, the following examples are only simple examples of the present invention and do not represent or limit the scope of the patent protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

[0049] As Figure 1As shown in the figure, the present invention provides a polyurethane cutting device, including a cutting tool 1, a tool table 3, a fixed pressing plate 4 and a pressing plate bracket (not shown). The cutting tool 1 is fixed on the tool table 3 by a high-strength bolt 2 passing through a through hole 9. Among them, the cutting tool 1 includes a cutting edge 101 and a tool body 102. The cutting edge 101 is fixed at the top of the tool body 102 and is used for cutting polyurethane. Among them, the cutting edge 101 has a main angle 7 and a secondary angle 8 within a specific range. As Figure 2 shown, it is a sectional view of the cutting edge 101 of the present invention. The main angle 7 of the cutting edge 101 is the included angle between the upper and lower surfaces of the cutting edge 101, which is 20 - 32°, and the secondary angle 8 is the included angle of the cutting edge part, which is 40 - 45°.

[0050] As Figure 1 shown, for the convenience of cutting, those skilled in the art can understand that when the cutting edge 101 is fixed to the tool body 102, the cutting edge part of the cutting edge 101 extends out of the main body part of the tool body 102, so that the tool body 102 will not interfere with the cutting of the polyurethane cylinder 5 by the cutting edge 101 during cutting. Preferably, as Figure 1 shown, the cutting edge 101 is embedded and fixed at the end of the tool body 102, and the secondary angle 8 part of the cutting edge extends out of the main body of the tool body 102. The length of the cutting edge 101 is the same as that of the tool body 102, and the width has no special limitation, as long as it is convenient to fix the cutting edge 101 at the end of the tool body 102, for example, 2.5 cm, but not limited thereto; the thickness of the cutting edge 101 also has no special limitation, as long as the secondary angle 8 of the cutting edge meets the foregoing requirements, for example, the thickness of the cutting edge 101 is 2 mm, 3 mm, etc., but not limited thereto.

[0051] The polyurethane cutting device of the present invention further includes a fixed pressing plate 4, which is used to press the polyurethane cylinder 5 placed on the bearing plate 6 during cutting. The fixed pressing plate 4 is connected to the tool table 3 through a pressing plate bracket (not shown) and moves synchronously with the tool table 3.

[0052] The process of the polyurethane cutting device of the present invention for cutting the polyurethane cylinder 5 is divided into two directions of movement: horizontal and vertical. During the cutting process, the fixed pressing plate 4 presses the polyurethane cylinder 5, and the bearing plate 6 drives the polyurethane cylinder 5 to move horizontally a certain distance in the direction close to the tool table 3. During this cutting process, the entire tool table 3, including the cutting tool 1 and the fixed pressing plate 4, remains stationary, thereby obtaining a polyurethane polishing pad with a certain thickness. Then the bearing plate 6 retreats the same distance in the horizontal direction. After the retreat is completed, the tool table 3 drives the fixed pressing plate 4 to descend by a target thickness, and then the above process is repeated to perform the second cutting action.

[0053] The present invention will be further explained and illustrated through more specific embodiments below, but it does not constitute any limitation.

[0054] Embodiment 1

[0055] This embodiment provides a tool for cutting polyurethane. The tool for cutting polyurethane includes a tool body and a cutting edge; the tool body and the cutting edge are welded by submerged arc welding;

[0056] The main angle of the cutting edge is 20°, and the secondary angle is 45°.

[0057] The length of the tool body is 1000 mm;

[0058] The material of the tool body is Q235 with HRC19.

[0059] The material of the cutting edge is tungsten carbide cobalt-based hard alloy with a Rockwell hardness of 70 HRC.

[0060] The length of the cutting edge is 1000 mm.

[0061] This embodiment also provides a polyurethane cutting device, which includes the above-mentioned tool for cutting polyurethane, a tool table, a pressing plate bracket and a fixed pressing plate;

[0062] The tool for cutting polyurethane is fixed on the tool table through a through hole, and a 10.9 grade high-strength bolt is arranged in the through hole;

[0063] The pressing plate bracket is welded on the tool table;

[0064] The fixed pressing plate is fixed on the pressing plate bracket and moves synchronously with the tool table; the material of the fixed pressing plate is cast iron after aging treatment;

[0065] The gap between the cutting edge of the tool for cutting polyurethane and the fixed pressing plate is 1.4 mm.

[0066] Embodiment 2

[0067] This embodiment provides a tool for cutting polyurethane. The tool for cutting polyurethane includes a tool body and a cutting edge; the tool body and the cutting edge are welded by submerged arc welding; the main angle of the cutting edge is 22°, and the secondary angle is 42°.

[0068] The length of the tool body is 980 mm;

[0069] The material of the tool body is 45 steel.

[0070] The material of the cutting edge is tungsten titanium-based hard alloy with a Rockwell hardness of 50 HRC.

[0071] The length of the cutting edge is 970 mm.

[0072] This embodiment also provides a polyurethane cutting device, which includes the above-mentioned tool for cutting polyurethane, a tool table, a pressing plate bracket and a fixed pressing plate;

[0073] The tool for cutting polyurethane is fixed on the tool table through a through hole, and a 9 - grade high - strength bolt is arranged in the through hole;

[0074] The pressing plate bracket is welded on the tool table;

[0075] The fixed pressing plate is fixed on the pressing plate bracket and moves synchronously with the tool table; the material of the fixed pressing plate is cast iron after aging treatment;

[0076] The gap between the cutting edge of the tool for cutting polyurethane and the fixed pressing plate is 1.34 mm.

[0077] Example 3

[0078] This example provides a tool for cutting polyurethane. The tool for cutting polyurethane includes a tool body and a cutting edge; the tool body and the cutting edge are welded by submerged arc welding; the main angle of the cutting edge is 25°, and the secondary angle is 40°.

[0079] The length of the tool body is 950 mm;

[0080] The material of the tool body is 45 - steel.

[0081] The material of the cutting edge is tungsten - tantalum - based cemented carbide with a Rockwell hardness of 60 HRC.

[0082] The length of the cutting edge is 950 mm.

[0083] This example also provides a polyurethane cutting device, which includes the above - mentioned tool for cutting polyurethane, a tool table, a pressing plate bracket and a fixed pressing plate;

[0084] The tool for cutting polyurethane is fixed on the tool table through a through hole, and an 8.8 - grade high - strength bolt is arranged in the through hole;

[0085] The pressing plate bracket is welded on the tool table;

[0086] The fixed pressing plate is fixed on the pressing plate bracket and moves synchronously with the tool table; the material of the fixed pressing plate is cast iron after aging treatment;

[0087] The gap between the cutting edge of the tool for cutting polyurethane and the fixed pressing plate is 1.53 mm.

[0088] Example 4

[0089] This example provides a tool for cutting polyurethane. Except that the material of the cutting edge is high - speed steel with a Rockwell hardness of 25 HRC, the rest are the same as those in Example 1.

[0090] This example also provides a polyurethane cutting device, which is the same as that in Example 1.

[0091] Comparative Example 1

[0092] This comparative example provides a tool for cutting polyurethane, and the tool for cutting polyurethane is the same as that in Example 1.

[0093] This example also provides a polyurethane cutting device. The polyurethane cutting device is the same as that in Example 1, except that the tool for cutting polyurethane is fixed on the tool post through a counterbore and no fixing pressure plate is provided.

[0094] Comparative Example 2

[0095] This comparative example provides a tool for cutting polyurethane, and the tool for cutting polyurethane is the same as that in Example 1.

[0096] This comparative example also provides a polyurethane cutting device. The polyurethane cutting device is the same as that in Example 1, except that the tool for cutting polyurethane is fixed on the tool post through a counterbore.

[0097] Comparative Example 3

[0098] This comparative example provides a tool for cutting polyurethane, and the tool for cutting polyurethane is the same as that in Example 1.

[0099] This comparative example also provides a polyurethane cutting device. The polyurethane cutting device is the same as that in Example 1, except that no fixing pressure plate is provided.

[0100] Comparative Example 4

[0101] This comparative example provides a tool for cutting polyurethane, and the tool for cutting polyurethane is the same as that in Example 1.

[0102] This comparative example also provides a polyurethane cutting device. The polyurethane cutting device is the same as that in Example 1, except that ordinary bolts are provided in the through holes.

[0103] Comparative Example 5

[0104] This comparative example provides a tool for cutting polyurethane. The tool for cutting polyurethane is the same as that in Example 1, except that the main angle of the cutting edge is 15°.

[0105] This comparative example also provides a polyurethane cutting device, and the polyurethane cutting device is the same as that in Example 1.

[0106] Comparative Example 6

[0107] This comparative example provides a tool for cutting polyurethane. The tool for cutting polyurethane is the same as that in Example 1, except that the secondary angle of the cutting edge is 35°.

[0108] This comparative example also provides a polyurethane cutting device, which is the same as that in Example 1.

[0109] Comparative Example 7

[0110] This comparative example provides a tool for cutting polyurethane, which is the same as that in Example 1.

[0111] This comparative example also provides a polyurethane cutting device, which is the same as that in Example 1 except that 8 - level high - strength bolts are arranged in the through - hole.

[0112] Comparative Example 8

[0113] This comparative example provides a tool for cutting polyurethane, which is the same as that in Example 1.

[0114] This comparative example also provides a polyurethane cutting device, which is the same as that in Example 1 except that the gap between the cutting edge of the tool for cutting polyurethane and the fixed pressing plate is 1.2 mm.

[0115] Comparative Example 9

[0116] This comparative example provides a tool for cutting polyurethane, which is the same as that in Example 1.

[0117] This comparative example also provides a polyurethane cutting device, which is the same as that in Example 1 except that the gap between the cutting edge of the tool for cutting polyurethane and the fixed pressing plate is 1.6 mm.

[0118] In the above - mentioned examples and comparative examples, the cutting device for cutting polyurethane is used to cut a cast - integrally - formed polyurethane cylinder. The cutting travel speed is 2 m / min, the temperature is 23 °C, and the cutting target range is 2.02 mm to 2.04 mm, obtaining a polyurethane polishing pad;

[0119] The diameter of the polyurethane cylinder is 1000 mm and the height is 10 cm;

[0120] The cutting resistance of each piece of the polyurethane cylinder is 45 tons;

[0121] When cutting the polyurethane cylinder, a fixed pressing plate is arranged at the top of the polyurethane cylinder.

[0122] A micrometer of Mitutoyo Japan with an accuracy of 0.001 mm is used to measure the thickness of the polyurethane polishing pads obtained in the above - mentioned examples and comparative examples. The nine - point thickness results and the thickness accuracy results of the polyurethane polishing pads are shown in Table 1.

[0123] Table 1

[0124]

[0125]

[0126] As can be seen from Table 1:

[0127] The tool for cutting polyurethane provided by the present invention is fixed on the tool table through a through hole. A high-strength bolt is arranged in the through hole, and at the same time, a fixed pressing plate is arranged to press on the integrally cast polyurethane cylinder for cutting, and a polyurethane polishing pad with high thickness precision and small surface roughness can be obtained, which is suitable for large-scale popularization and application.

[0128] When the main angle or the secondary angle of the cutting edge is small, it will lead to poor quality of the polyurethane polishing pad obtained by cutting, large thickness precision, and shortened service life of the tool, resulting in poor economy.

[0129] When the strength of the high-strength bolt arranged in the through hole is insufficient, it will also affect the quality of the polyurethane polishing pad obtained by cutting.

[0130] When the gap between the cutting edge of the tool for cutting polyurethane and the fixed pressing plate is small or large, it will lead to the thickness of the polyurethane polishing pad obtained by cutting not meeting the requirements, affecting the use.

[0131] When the material of the cutting edge does not use the cemented carbide in the present invention but uses conventional high-speed steel, the thickness precision of the polyurethane polishing pad obtained by cutting is much better than that of the comparative example. Only the surface roughness is relatively large, but it can still meet the application requirements; at the same time, because the hardness of high-speed steel is not as high as that of cemented carbide, compared with the cutting edge made of cemented carbide, the service life of the high-speed steel cutting edge tool will be shortened, resulting in relatively poor economy.

[0132] The applicant declares that the above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A tool for cutting polyurethane, characterized in that, the tool for cutting polyurethane comprises a tool body and a cutting edge; the tool body and the cutting edge are fixedly connected; the main angle of the cutting edge is 20 - 32°, and the secondary angle is 40 - 45°; the material of the cutting edge is selected from hard materials with a Rockwell hardness ≥ 25HRC.

2. The tool according to claim 1, characterized in that, the fixed connection is welding, more preferably submerged arc welding or brazing; preferably, the length of the tool body is 660 - 1100 mm.

3. The tool according to claim 1 or 2, characterized in that, the material of the tool body is selected from materials with a Rockwell hardness > 15HRC, preferably including 45 steel; and / or the material of the cutting edge includes cemented carbide, preferably at least any one of tungsten-titanium based cemented carbide, tungsten-cobalt based cemented carbide, tungsten-tantalum based cemented carbide, and titanium carbide based cemented carbide.

4. The tool according to any one of claims 1 - 3, characterized in that, the length of the cutting edge is 660 - 1100 mm.

5. A polyurethane cutting device, characterized in that, the polyurethane cutting device comprises a tool for cutting polyurethane according to any one of claims 1 - 4, a tool table, a pressing plate support, and a fixed pressing plate; the tool for cutting polyurethane is fixed on the tool table through a through hole, and 8.8 - 10.9 grade high-strength bolts are arranged in the through hole; the pressing plate support is connected to the tool table; the fixed pressing plate is fixed on the pressing plate support and moves synchronously with the tool table; the gap between the cutting edge of the tool for cutting polyurethane and the fixed pressing plate is 1.34 - 1.53 mm.

6. The polyurethane cutting device according to claim 5, characterized in that, the material of the fixed pressing plate includes cast iron after aging treatment.

7. A polyurethane cutting method, characterized in that, using the polyurethane cutting device according to claim 5 or 6 to cut a cast-in-one polyurethane cylinder to obtain a polyurethane polishing pad.

8. The polyurethane cutting method according to claim 7, characterized in that, the diameter of the polyurethane cylinder is 660 - 1000 mm, and the height is 6 - 15 cm.

9. The polyurethane cutting method according to claim 7 or 8, characterized in that, when cutting the polyurethane cylinder, a fixed pressing plate is arranged at the top of the polyurethane cylinder; preferably, when cutting the polyurethane cylinder, the straightness of the tool for cutting polyurethane is - 10 - 10 μm; more preferably, the cutting resistance of each piece of the polyurethane cylinder is 40 - 50 tons.

10. The polyurethane cutting method according to any one of claims 7 - 9, characterized in that, the thickness accuracy of the polyurethane polishing pad is - 10 - 10 μm; preferably, the surface roughness of the polyurethane polishing pad is 2 - 6.5 μm, preferably 2 - 4 μm.

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