Micro powder processing equipment
The fine grinding apparatus addresses the challenge of pulverizing low-melting-point resins by using sliding members with protrusions and a cooling system, achieving efficient and cost-effective pulverization.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- 株式会社MSC
- Filing Date
- 2023-10-10
- Publication Date
- 2026-05-21
AI Technical Summary
Existing methods struggle to efficiently pulverize resins with low melting points and elasticity, such as polyethylene (PE) and polypropylene (PP), due to mixing issues and high operational costs associated with cryogenic pulverization.
A fine grinding apparatus with a grinding section using sliding members with radial protrusions, a material supply system, a collection system, and a cooling mechanism to suppress temperature rise and facilitate efficient pulverization of various materials, including low-melting-point resins.
The apparatus effectively pulverizes low-melting-point resins by suppressing temperature rise and kneading, allowing for simple and cost-effective fine grinding of diverse materials.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to a fine pulverization processing apparatus for pulverizing materials.
Background Art
[0002] In recent years, for the construction of a resource recycling society, the importance of advanced material recycling has been increasing. However, at recycling sites, it is rare to handle waste plastics that contain no impurities. Usually, it is necessary to mix multiple plastic materials that do not mix with each other, inorganic minerals, additives, etc. "Pseudo-compatibility" is a measure of "whether they are mixed", and the degree of dispersion (size of dispersed particles) in a polymer mixture system serves as a criterion for judging pseudo-compatibility. For plastic raw materials, by processing them into a finer state, pseudo-compatibility can be enhanced, enabling high-quality recycling. Therefore, the development of an apparatus that enables fine pulverization is required.
[0003] For example, Patent Document 1 shows equipment that further finely pulverizes flaky waste plastics using the rotation of a rotary blade. Also, for example, Non-Patent Document 1 shows a method called cryogenic pulverization, in which raw materials are immersed in liquid nitrogen at -196 °C to embrittle them, thereby performing pulverization processing on rubber and resins that are difficult to pulverize at normal temperature.
Prior Art Documents
Patent Documents
[0004]
Patent Document 1
Non-Patent Documents
[0005]
Non-Patent Document 1
[0006] However, while the method described in Patent Document 1 can finely pulverize plastics with high melting points, such as flake-shaped polyethylene terephthalate (PET) resin, it has the problem that it is difficult to use with resins that have low melting points and elasticity, such as polyethylene (PE) and polypropylene (PP), because they get mixed into the crusher.
[0007] Furthermore, while the method described in Reference 2 can produce fine powders of low-melting-point, elastic resins such as PE and PP, it requires pre-freezing the raw materials in liquid nitrogen, and the equipment itself must be made of metal and designed to withstand operation in contact with liquid nitrogen. This results in high labor costs, equipment costs, and running costs, making it unprofitable.
[0008] This invention was made based on these problems and aims to provide a fine grinding device that can easily finely grind various materials with a simple configuration. [Means for solving the problem]
[0009] The present invention provides a fine grinding apparatus for processing waste containing resin as a material, and comprises a grinding section that grinds the material by grinding a first sliding member and a second sliding member, each having a plurality of protrusions extending radially on at least a portion of their opposing surfaces; a material supply means for supplying material to the grinding section; a collection means for collecting the pulverized material in the grinding section; and a cooling means for cooling the grinding section. [Effects of the Invention]
[0010] According to the present invention, the material is crushed by rubbing together a first joint member and a second joint member, each having multiple radially extending protrusions. As the material is crushed while rapidly passing between the protrusions of the first and second joint members, the temperature rise of the material can be suppressed, and the occurrence of kneading can be suppressed. Furthermore, since the crushing section is cooled by a cooling means, the temperature rise of the material can be further suppressed. Therefore, even resins with low melting points can be finely crushed, and various materials can be easily finely crushed with a simple configuration.
[0011] In particular, by configuring the system so that at least one of the first sliding member and the second sliding member is rotated to bring their opposing surfaces together, and by providing a material supply port connected to a material supply means in the center of the first sliding member or the second sliding member, the material can be more quickly passed between the protrusions and pushed outwards by utilizing centrifugal force.
[0012] Furthermore, by setting the spacing between the protrusions of the first and second joint members to within the range of 0.5 mm to 0.6 mm, the inner width of each protrusion to within the range of 0.5 mm to 0.6 mm, the outer width of each protrusion to within the range of 0.9 mm to 1.2 mm, and the height of each protrusion to within the range of 0.8 mm to 0.9 mm, fine grinding can be easily achieved.
[0013] Furthermore, if the cooling means includes a cooling device body that cools and discharges compressed air, a nozzle attached to the cooling device body, a compressed air supply means that supplies compressed air to the cooling device body, and piping that guides compressed air from the compressed air supply means to the cooling device body, the device can be simplified and cooling can be performed effectively.
[0014] In addition, by providing a spraying mechanism for spraying water onto the material supplied to the grinding section, the temperature rise of the material during fine grinding can be further suppressed by increasing the moisture content on the material surface.
[0015] Furthermore, if the recovery means is provided with a sieve section and a re-supply pipe for returning the crushed material that has not passed through the sieve section to the crushing section, it is possible to suppress the generation of kneading and perform fine pulverization while maintaining a large throughput.
Brief Description of the Drawings
[0016] [Figure 1] It is a diagram showing the overall configuration of a fine pulverization processing apparatus according to an embodiment of the present invention. [Figure 2] It is a diagram showing a schematic configuration of a cross-section along the line I-I shown in FIG. 1. [Figure 3] It is a diagram showing a schematic configuration of a cross-section along the line II-II shown in FIG. 2. [Figure 4] It is a diagram showing a schematic configuration of a cross-section along the line III-III shown in FIG. ②. [Figure 5] It is a diagram showing an enlarged view of a part of a cross-section along the line IV-IV shown in FIG. 3. [Figure 6] It is a diagram showing a part of a cross-section along the line V-V shown in FIG. 1. [Figure 7] It is a diagram showing the configuration of a modification of the present invention.
Modes for Carrying Out the Invention
[0017] Hereinafter, embodiments of the present invention will be described in detail.
[0018] (One Embodiment) FIG. 1 shows the overall configuration of a fine pulverization processing apparatus 1 according to an embodiment of the present invention. FIG. 2 shows a schematic configuration of a cross-section along the line I-I shown in FIG. 1. FIG. 3 shows a schematic configuration of a cross-section along the line II-II shown in FIG. 2. FIG. 4 shows a schematic configuration of a cross-section along the line III-III shown in FIG. 2. FIG. 5 shows an enlarged view of a part of a cross-section along the line IV-IV shown in FIG. 3. FIG. 6 shows a part of a cross-section along the line V-V shown in FIG. 1.
[0019] This micro-pulverization apparatus 1 is used to pulverize materials, for example, to further pulverize materials that have been pulverized into flakes. Preferred materials include, for example, waste containing resin. Typical examples of resin-containing waste include materials containing polyolefin resins such as PE and PP. Furthermore, it is possible to process not only polyolefins, but also materials containing polystyrene (PS) and polyvinyl chloride (PVC), which were difficult to pulverize with conventional pulverizers. In addition, materials that are difficult to pulverize, such as polyamide (PA) and low-temperature elastomers, may be included in small amounts, for example, 10% by mass or less. Moreover, materials containing polyethylene terephthalate (PET), ABS resin, thermosetting resin, engineering plastics, or super engineering plastics, which can be pulverized with conventional pulverizers, are also possible.
[0020] Waste materials may consist of one type of material or may contain two or more types of materials. For example, it may be a composite film made by laminating at least an olefin resin film with another synthetic resin film. It may also contain resin and materials other than resin. Examples of materials other than resin include metals, glass, inorganic additives, inks, and colorants. For example, it may be a composite film having a resin film and a metal foil such as aluminum foil, a printed film using printing ink, a colored film using a colorant, a resin film with metals or titanium dioxide added, an optical cable, a plastic product containing ink or a small amount of sand, or a home appliance containing metal. The waste materials may be used waste materials, unused scraps or defective products generated in the production process, or a mixture of new and waste materials.
[0021] This fine grinding apparatus 1 includes, for example, a grinding unit 10 for grinding materials, a material supply means 20 for supplying materials to the grinding unit 10, a recovery means 30 for collecting the pulverized material in the grinding unit 10, a cooling means 40 for cooling the grinding unit 10, and a spraying means 50 for spraying water onto the material supplied to the grinding unit 10.
[0022] The crushing section 10 is configured to crush the material by sliding a first sliding member 11 and a second sliding member 12 together. The first sliding member 11 and the second sliding member 12 are made of, for example, cemented carbide or a metallic material with a cemented carbide layer formed on its surface. The first sliding member 11 and the second sliding member 12 are arranged facing each other, and at least a portion of their opposing surfaces has a plurality of radially extending protrusions 13 formed on each. This allows the material to pass quickly between the protrusions 13 of the first sliding member 11 and the second sliding member 12 while being crushed. Note that Figures 3 to 5 conceptually represent the configuration of the protrusions 13 and do not correspond to actual dimensions.
[0023] The crushing unit 10 is preferably configured to bring together the opposing surfaces of the first sliding member 11 and the second sliding member 12 by rotating at least one of them along their opposing surfaces, and it is preferable that a material supply port 14 connected to the material supply means 20 is provided in the center of the first sliding member 11 or in the center of the second sliding member 12. This is because centrifugal force can be used to more quickly pass the material between each projection 13 and push it outwards. In this embodiment, for example, a case in which the first sliding member 11 is rotated, the second sliding member 12 is fixed, and a material supply port 14 is provided in the center of the second sliding member 12 will be described.
[0024] The first sliding member 11 is provided with a guide region 11A in the area corresponding to the material supply port 14, which guides the material supplied to the material supply port 14 outward (i.e., towards the outer circumference), and a first sliding region 11B is provided outside the guide region 11A, on which a projection 13 is formed. The guide region 11A is provided with, for example, a plurality of projection-like wings 15 extending outward from the center. It is preferable that the wings 15 protrude more towards the second sliding member 12 than the projection 13. This is to scrape the material supplied to the material supply port 14 and guide it outward. The number of wings 15 is preferably, for example, 2 to 8. On the side of the first sliding member 11 opposite to the second sliding member 12, a rotating shaft 16 extends from the center, and a driving means 17 such as a motor is connected to it. The second sliding member 12 is provided with a material supply port 14 in the center, and a second sliding region 12A is provided on the outside of it, with a projection 13 formed thereon corresponding to the first sliding region 11B.
[0025] Preferably, each projection 13 has a triangular cross-sectional shape on the surface side in a direction perpendicular to the extending direction. Specifically, it is preferable that, for example, one end of each projection 13 adjacent to another projection 13 protrudes further outward than the other end, and the surface of each projection 13 is an inclined surface in which one end protrudes further outward than the other end. Furthermore, it is preferable that when each projection 13 of the first sliding member 11 and each projection 13 of the second sliding member 12 are individually positioned facing each other, one end (i.e., the protruding side) and the other end (i.e., the non-protruding side) face each other.
[0026] The spacing T1 between each projection 13 is preferably, for example, within the range of 0.5 mm to 0.6 mm. The inner width W1 in the radial direction of each projection 13 is preferably, for example, within the range of 0.5 mm to 0.6 mm, and the outer width W2 in the radial direction of each projection 13 is preferably, for example, within the range of 0.9 mm to 1.2 mm. The height H of each projection 13 (height on the protruding side) is preferably, for example, within the range of 0.8 mm to 0.9 mm. The distance T2 between each projection 13 of the first sliding member 11 and each projection 13 of the second sliding member 12 is preferably, for example, 0.01 mm to 0.5 mm, more preferably within the range of 0.01 mm to 0.03 mm, and even more preferably within the range of 0.01 mm to 0.15 mm. The spacing T1, widths W1, W2, and height H of the protrusions 13, and the distance T2 between each protrusion 13 of the first joint member 11 and the second joint member 12 are such that the smaller the values, the more finely the material can be pulverized. However, if the values are made too small, the processing volume will decrease, and consideration will be needed regarding thermal expansion during pulverization.
[0027] The first sliding member 11 and the second sliding member 12 are housed, for example, inside the cover body 18, and the pulverized material produced by the sliding action of the first sliding member 11 and the second sliding member 12 is pushed out from the outside into the inside of the cover body 18.
[0028] The material supply means 20 includes, for example, a material quantitative dispenser 21 positioned above the material supply port 14 to supply a predetermined amount of material, and a material supply pipe 22 that guides the material from the material quantitative dispenser 21 to the material supply port 14. In the material supply pipe 22, the material moves to the material supply port 14 by gravity. The material supplied by the material supply means 20 is preferably, for example, in the form of flaked material.
[0029] The recovery means 30 includes, for example, a temporary storage section 31 for temporarily storing the crushed material, a guide tube 32 for guiding the crushed material from inside the cover body 18 to the temporary storage section 31, and a suction means (not shown) for moving the crushed material from the cover body 18 to the temporary storage section 31 by suction. The guide tube 32 includes, for example, an upper guide tube 32A for guiding the crushed material from the upper side of the cover body 18 to the temporary storage section 31, and a lower guide tube 32B for guiding the crushed material from the lower side of the cover body 18 to the temporary storage section 31. The suction means is connected to the temporary storage section 31 via a suction tube 33.
[0030] The recovery means 30 also includes, for example, a sieving section 34 that separates the crushed material by size, a crushed material quantitative feeder 35 that supplies the crushed material from the temporary storage section 31 to the sieving section 34 in a predetermined amount, a resupply pipe 36 that guides the crushed material that did not pass through the sieving section 34 from the sieving section 34 to the material supply port 14 of the crushing section 10, and a discharge section 37 that discharges the crushed material that has passed through the sieving section 33.
[0031] The sieving section 34 is, for example, located below the temporary storage section 31 and above the material supply port 14 of the crushing section 10. The sieving section 34 is preferably composed of, for example, a vibrating sieve, and preferably a two-stage type. The size of the sieve mesh is preferably such that the size of the crushed material passing through the sieving section 34 is 0.5 mm or less, and more preferably 0.2 mm or less. In the resupply pipe 36, the crushed material moves to the material supply port 14 by gravity.
[0032] The cooling means 40 is configured to cool at least one of the first sliding member 11 and the second sliding member 12 with a cooling medium. In this embodiment, for example, the second sliding member 12 is cooled with a cooling medium, thereby indirectly cooling the first sliding member 11 as well, and thus the temperature rise of the material can be suppressed. Specifically, it is preferable that the cooling means 40 includes, for example, a cooling device body 41 that cools compressed air and discharges cooled air, a nozzle 42 attached to the cooled air discharge port of the cooling device body 41, a compressed air supply means 43 such as a compressor that supplies compressed air to the cooling device body 41, and piping 44 that guides compressed air from the compressed air supply means 43 to the cooling device body 41. This is because the device can be simplified and cooling can be performed effectively. Note that the cooling means 40 is omitted in Figures 1 and 2 for clarity of the configuration.
[0033] Furthermore, for example, the second sliding member 12 and the cover body 18 are provided with a plurality of insertion holes 12B and through holes 18A for inserting the nozzle 42 of the cooling means 40. The insertion holes 12B are preferably non-through holes, provided from the outside of the second sliding member 12 to the vicinity of each projection 13. The through holes 18A are, for example, provided to penetrate the cover body 18 corresponding to each insertion hole 12B. The insertion holes 12B are, for example, provided at intervals around the material supply port 14, and it is preferable to provide multiple types with different distances from the material supply port 14. In the drawings of this embodiment, the case where two insertion holes 12B are arranged on the side of the material supply port 14 and two on the outer circumference is shown, arranged alternately along the circumferential direction of the material supply port 14. For clarity of the configuration, Figure 6 omits the nozzle 42 inserted into the insertion hole 12B on the side of the material supply port 14, the cooling device body 41, and the piping 44 connected thereto.
[0034] Preferably, the cooling means 40 controls the drive using a control means (not shown) according to, for example, the internal temperature of the cover body 18, the temperature of the first sliding member 11, or the temperature of the second sliding member 12.
[0035] The spraying means 50, for example, sprays water in a mist form onto the material, thereby increasing the moisture content on the material surface and suppressing the temperature rise of the material during fine grinding. The spraying means 50 is, for example, installed on the material supply pipe 22. The spraying means 50 is preferably used as needed, depending on the type of material to be finely ground.
[0036] This pulverization apparatus 1 operates as follows to pulverize materials. First, for example, material pulverized into flakes is fed into the material quantitative feeder 21. The material quantitative feeder 21 supplies a predetermined amount of material to the material supply port 14 of the pulverization section 10 via the material supply pipe 22. At this time, if necessary depending on the type of material, water is sprayed onto the material by the spraying means 50. The material supplied to the material supply port 14 is pushed outward by the rotation of the vanes 15 formed in the guide region 11A as the first joint member 11 rotates, for example, and reaches the opposing region between the first joint region 11B and the second joint region 12A. In the opposing region between the first joint region 11B and the second joint region 12A, the material is pushed outward while being pulverized by, for example, the centrifugal force due to the rotation of the first joint member 11 and the airflow caused by suction by the suction means of the recovery means 30. In this case, if necessary depending on the type of material, the crushing section 10 is cooled by the cooling means 40.
[0037] The pulverized material, crushed by the first joint member 11 and the second joint member 12, is pushed out from the outside into the cover body 18, for example, and is stored in the temporary storage section 31 via the upper guide tube 32A and the lower guide tube 32B by suction from the suction means of the recovery means 30. The pulverized material stored in the temporary storage section 31 is supplied in a predetermined amount to the sieve section 34 by the pulverized material quantitative feeder 35, and the pulverized material that passes through the sieve section 34 is discharged from the discharge section 37. The pulverized material that does not pass through the sieve section 34 is guided to the material supply port 14 of the grinding section 10 via the resupply tube 36 and is ground again in the grinding section 10.
[0038] As described above, according to this embodiment, the material is crushed by rubbing together a first sliding member 11 and a second sliding member 12, each having multiple radially extending protrusions 13. As the material is crushed while rapidly passing between the protrusions 13 of the first sliding member 11 and the second sliding member 12, the temperature rise of the material can be suppressed, and the occurrence of kneading can be suppressed. Furthermore, since the crushing section 10 is cooled by the cooling means 40, the temperature rise of the material can be further suppressed. Therefore, even resins with low melting points can be finely crushed, and various materials can be easily finely crushed with a simple configuration.
[0039] In particular, by configuring the system so that at least one of the first sliding member 11 and the second sliding member 12 is rotated to slide their opposing surfaces together, and by providing a material supply port 14 connected to the material supply means 20 in the center of either the first sliding member 11 or the second sliding member 12, the material can be more quickly passed between the protrusions and pushed outwards by utilizing centrifugal force.
[0040] Furthermore, if the spacing T between the protrusions 13 of the first joint member 11 and the second joint member 12 is set to a range of 0.5 mm to 0.6 mm, the inner width W1 of each protrusion 13 is set to a range of 0.5 mm to 0.6 mm, the outer width W2 of each protrusion 13 is set to a range of 0.9 mm to 1.2 mm, and the height H of each protrusion 13 is set to a range of 0.8 mm to 0.9 mm, then fine grinding can be easily achieved.
[0041] Furthermore, if the cooling means 40 includes a cooling device body 41 that cools and discharges compressed air, a nozzle 42 attached to the cooling device body 41, a compressed air supply means 43 that supplies compressed air to the cooling device body 41, and piping 44 that guides compressed air from the compressed air supply means 43 to the cooling device body 41, the device can be simplified and cooling can be performed effectively.
[0042] In addition, by providing a spraying means 50 for spraying water onto the material supplied to the grinding unit 10, the temperature rise of the material during fine grinding can be further suppressed by increasing the moisture content on the material surface.
[0043] Furthermore, by providing the recovery means 30 with a sieving section 34 and a resupply pipe 36 that returns the pulverized material that did not pass through the sieving section 34 back to the pulverizing section 10, it is possible to maintain a large processing capacity while suppressing the occurrence of kneading and achieving fine pulverization.
[0044] In this embodiment, using the fine grinding apparatus 1 described above, a plastic container made of injection-molded polypropylene was prepared as resin-containing waste and subjected to fine grinding. The spacing T1 between each protrusion 13 in the grinding section 10 was set to 0.5 mm or more and 0.6 mm or less, the inner width W1 in the radial direction of each protrusion 13 was set to 0.5 mm or more and 0.6 mm or less, the outer width W2 in the radial direction of each protrusion 13 was set to 0.9 mm or more and 1.2 mm or less, the height H of each protrusion 13 was set to 0.8 mm or more and 0.9 mm or less, and the distance T2 between each protrusion 13 of the first joint member 11 and the second joint member 12 was set to 0.01 mm or more and 0.5 mm or less. The resin-containing waste was supplied to the material supply means 20 in flake form, and water was sprayed onto the material by the spraying means 50. Furthermore, the grinding section 10 was cooled by the cooling means 40 while the material was finely ground.
[0045] As a result, no resin incorporation was observed in the fine grinding apparatus 1, and ground material with a size of 0.5 mm or less was obtained.
[0046] (modified version) In the above embodiment, a cooling device body 41 that cools compressed air and discharges cooled air was described as the cooling means 40. However, for example, as shown in Figure 7, a refrigerant flow passage 45 for circulating a cooling medium such as water may be provided inside at least one of the first sliding member 11 and the second sliding member 12, and the cooling medium may be cooled and circulated using a heat exchanger (not shown) to cool it. In Figure 7, the case in which the refrigerant flow passage 45 is provided inside the second sliding member 12 is shown. Even with this configuration, the same operation and effects as in the above embodiment can be obtained.
[0047] Although the present invention has been described above with reference to embodiments, the present invention is not limited to the above embodiments and can be modified in various ways. For example, although each component was described in detail in the above embodiments, it is not necessary to have all components, and other components may also be included.
[0048] Furthermore, although the above embodiment describes a case in which the first sliding member 11 is rotated and the second sliding member 12 is fixed, both the first sliding member 11 and the second sliding member 12 may be rotated, or the first sliding member 11 may be fixed and the second sliding member 12 may be rotated. Moreover, although the above embodiment describes a case in which a material supply port 14 is provided in the center of the second sliding member 12, the material supply port 14 may be provided in the center of the first sliding member 11.
[0049] In addition, although the above embodiment describes a case in which the second sliding member 12 is cooled by a cooling medium, thereby indirectly cooling the first sliding member 11, the first sliding member 11 may be cooled by a cooling medium, thereby indirectly cooling the second sliding member 12, or both the first sliding member 11 and the second sliding member 12 may be cooled by a cooling medium. [Explanation of Symbols]
[0050] 1...Fine grinding processing device, 10...Grinding section, 11...First joint member, 11A...Guide area, 11B...First joint area, 12...Second joint member, 12A...Second joint area, 12B...Insertion hole, 13...Protrusion, 14...Material supply port, 15...Blade, 16...Rotating shaft, 17...Driving means, 18...Cover body, 18A...Through hole, 20...Material supply means, 21...Material quantitative supply machine, 2 2...Material supply pipe, 30...Recovery means, 31...Temporary storage section, 32...Guide pipe, 32A...Upper guide pipe, 32B...Lower guide pipe, 33...Suction pipe, 34...Sieve section, 35...Powder quantity supply machine, 36...Resupply pipe, 37...Discharge section, 40...Cooling means, 41...Cooling device body, 42...Nozzle, 43...Compressed air supply means, 44...Piping, 45...Refrigerant flow passage, 50...Spraying means
Claims
1. A fine grinding apparatus for grinding waste containing resin as a material, A grinding section that grinds a material by grinding a first grinding member and a second grinding member, each having a plurality of protrusions extending radially on at least a portion of their opposing surfaces, A material supply means for supplying material to the grinding section, A recovery means for recovering the pulverized material in the aforementioned pulverization section, It includes a cooling means for cooling the grinding section, The first and second sliding members are such that the spacing between each projection is within the range of 0.5 mm to 0.6 mm, the inner width of each projection is within the range of 0.5 mm to 0.6 mm, the outer width of each projection is within the range of 0.9 mm to 1.2 mm, and the height of each projection is within the range of 0.8 mm to 0.9 mm. A fine grinding processing apparatus characterized by the following features.
2. The grinding unit is configured to rub against each other's opposing surfaces by rotating at least one of the first sliding member and the second sliding member, and a material supply port connected to the material supply means is provided in the center of the first sliding member or the center of the second sliding member. The fine grinding apparatus according to claim 1, characterized in that it is a fine grinding apparatus.
3. The fine grinding apparatus according to claim 1, characterized in that the cooling means comprises a cooling device body that cools and discharges compressed air, a nozzle attached to the cooling device body, a compressed air supply means that supplies compressed air to the cooling device body, and piping that guides compressed air from the compressed air supply means to the cooling device body.
4. The fine grinding apparatus according to claim 1, characterized in that the cooling means has a refrigerant flow passage for circulating a cooling medium inside at least one of the first sliding member and the second sliding member.
5. Furthermore, the fine grinding apparatus according to claim 1 is characterized by being equipped with a spraying means for spraying water onto the material supplied to the grinding section.