JP2019037948A - Mill - Google Patents

Abstract

To provide a mill in which a clearance between a lower grind stone and an upper grind stone can be adjusted with higher accuracy.SOLUTION: The mill comprises: a device body 2 comprising a lower grind stone 9 which is rotatable and vertically movable; a top cover 3 comprising an upper grind stone 10 which is opposite to the lower grind stone 9; a sensor 22 which is provided on the device body 2 or the top cover 3, and measures vibration or a sound during operation; and clearance adjustment means which vertically moves the lower grind stone 9, and adjusts an opposite distance between a milling top face 12 and a milling underside 13. The sensor 22 acquires data of vibration or a sound occurring in the state that the lower grind stone 9 is rotated, and there is no milled material on the milling top face 12 and the milling underside 13, and the clearance adjustment means can vertically move the lower grind stone 9 based on said data for the purpose of adjustment of the opposite distance.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an attritor for producing ultrafine particles that can be used in the fields of food, chemistry, pharmaceuticals, fuels, and the like.

  As a grinding machine capable of producing ultrafine particles by pulverizing a material, one having two upper and lower grindstones applying the principle of a stone mortar is known. For example, in Patent Document 1, as the applicant of the present application, a ring-shaped lower grindstone provided rotatably with respect to the apparatus main body, and a ring-shaped upper portion fixed to the lid and facing the lower grindstone. A mill with a grinding wheel is shown. In such an attritor, the lower grindstone is rotated while feeding the material between the lower grindstone and the upper grindstone, and the material is ground and pulverized into ultrafine particles by a combined action such as compression, shearing, and friction generated between the grindstones. Yes.

  By the way, in such an attritor, it is important that the particle size of the obtained ultrafine particles is kept constant. For this purpose, the clearance between the lower grindstone and the upper grindstone must not be changed. . However, even if the clearance adjustment between the lower grindstone and the upper grindstone is performed at the start of operation, the clearance varies depending on various factors. For example, if the operation is continued, the grinding wheel surface is worn by the grinding of the material, so that the clearance between the grinding stones gradually increases. Further, when the grindstone or the device is thermally expanded due to the temperature of the material or frictional heat generated during pulverization, the clearance between the grindstones is changed.

  With respect to such a problem, the grinding machine disclosed in Patent Document 1 includes a servo motor having a torque limiting function for moving the lower grindstone up and down, and during operation, the servo motor is driven to raise the lower grindstone so that the upper grindstone is raised. The lower grindstone is lowered to a predetermined clearance immediately after the servo motor is stopped by the torque signal of the servo motor at that time, and this operation is intermittently repeated a plurality of times.

Japanese Patent No. 3558687

  According to the method of Patent Document 1 described above, it is possible to automatically operate the grinder while keeping the particle size of the material to be ground constant. However, when the clearance between the grindstones is to be adjusted with higher accuracy, the difference in torque between the state where the grindstones are separated from each other and the state where the distant grindstones are in slight contact is small, which is a reference for clearance adjustment. In some cases, it may be difficult to detect a state in which the grindstone is slightly in contact. Further, when the factors of the clearance fluctuation between the lower grindstone and the upper grindstone were further explored, in addition to the above-described wear and thermal expansion of the grindstone surface, various members that rotate or move the lower grindstone as the operation continued were found. Wearing was also found to be a factor. That is, since worn members affect the accuracy of the clearance between the grindstones, it is also necessary to be able to appropriately grasp the replacement time of these members.

  An object of the present invention is to provide a grinder capable of adjusting the clearance between a lower grindstone and an upper grindstone with higher accuracy.

  The present invention includes an apparatus main body provided with a ring-shaped lower grindstone provided rotatably and vertically movable, and an annular upper grindstone provided so as to be openable and closable with respect to the apparatus main body and facing the lower grindstone. An upper lid, a sensor provided on the apparatus main body or the upper lid, for measuring vibration or sound during operation, and moving the lower whetstone up and down to a grinding upper surface of the lower whetstone and a grinding lower surface of the upper whetstone In the grinding machine comprising clearance adjusting means for adjusting the facing distance, the sensor rotates the lower grindstone, and the vibration or sound generated when the material to be ground does not exist on the grinding upper surface and the grinding lower surface. The data is acquired, and the clearance adjusting means is a grinder capable of moving the lower grindstone up and down based on the data for adjusting the facing distance.

  Moreover, it is preferable that the said clearance adjustment means can move the said lower grindstone up and down based on the data in the specific frequency contained in the said data.

  The apparatus main body or the upper lid includes a discharge unit that discharges the material crushed by the lower grindstone and the upper grindstone, and the discharge unit includes a temperature sensor that measures the temperature of the crushed material. It is preferable that the clearance adjusting means can move the lower grindstone up and down based on temperature data of a material obtained by the temperature sensor.

  The present invention also provides an apparatus main body including a ring-shaped lower grindstone that is rotatable and vertically movable, and an ring-shaped upper grindstone that is provided to be openable and closable with respect to the apparatus main body and faces the lower grindstone. An upper lid provided on the apparatus main body or the upper lid, and a sensor for measuring vibration or sound during operation; an upper grinding surface on the lower grinding stone by moving the lower grinding stone up and down; and a lower grinding surface on the upper grinding stone And a clearance adjusting means for adjusting the facing distance of the apparatus, wherein the apparatus main body has a rotating means for rotating the lower grindstone, and the sensor generates vibrations in a state where the lower grindstone is rotated. Or, the sound is measured at the initial stage of operation to obtain initial data and measured after a predetermined time of operation to obtain time-lapse data. Further, the initial data and the time-lapse data are compared. It is also a grinder comprising abnormality diagnosis means for detecting an abnormality of the rotation means, and said clearance adjusting means Te.

  The attritor of the present invention includes a sensor for measuring vibration or sound during operation. And by using this sensor and using the data obtained by measuring the vibration or sound generated when the lower grindstone is rotated, the clearance adjustment reference where the lower grindstone and the upper grindstone are in slight contact can be made with high accuracy. Can be detected. Further, by using this data, it is possible to detect an abnormality of a member that rotates or moves the lower grindstone, so that it is possible to remove the influence of a worn member that leads to a variation in clearance. Thus, according to the grinding machine of the present invention, the problems of the conventional grinding machine can be solved, and the clearance between the lower grinding wheel and the upper grinding wheel can be adjusted with higher accuracy.

It is sectional drawing which showed one Embodiment of the grinder according to this invention. It is a figure which shows the relationship between the frequency and amplitude level of the vibration obtained by the vibration sensor. It is a figure which shows the relationship between the frequency and amplitude level of the sound obtained by the sound sensor.

  Hereinafter, an embodiment of a grinder according to the present invention will be described with reference to FIG.

  In FIG. 1, the code | symbol 1 has shown the attrition machine of this embodiment. The attritor 1 is connected to an apparatus main body 2 including main members of the apparatus (a frame that forms the skeleton of the apparatus, a power source that controls the operation of the apparatus, a control unit, and the like) by a hinge or the like above the apparatus main body 2. 2 and an upper lid 3 that can be opened and closed.

  The apparatus main body 2 includes a main motor 4 for rotating a lower grindstone described later. The main motor 4 is attached so that the main shaft 5 is directed upward. The main shaft 5 is connected to a lower portion of a connecting member 6 having a cylindrical shape. A spline shaft 7 that is splined to the connection member 6 is provided above the connection member 6 at a position that is concentric with the connection member 6. Further, a disk-shaped rotating disk 8 is provided above the spline shaft 7, and a ring-shaped lower grindstone 9 is provided on the rotating disk 8. As described above, the lower grindstone 9 of the present embodiment can be rotated by the rotating means including the main motor 4, the main shaft 5, the connecting member 6, the spline shaft 7, and the rotating disk 8.

  The upper lid 3 is provided with a ring-shaped upper grindstone 10 provided to face the lower grindstone 9. The upper grindstone 10 of this embodiment is attached to the upper lid 3 so as not to rotate. In addition, an opening 11 communicating with a hole in the central portion of the upper grindstone 10 is provided in the central portion of the upper lid 3. Although illustration is omitted, a hopper or the like can be attached to the opening 11, and the material to be crushed through the opening 11 can be supplied to the grinder 1.

  The lower grindstone 9 and the upper grindstone 10 of this embodiment have a flat surface for pulverizing the material at the outer periphery thereof. Moreover, the center part is provided with a frusto-conical frustoconical part provided so as to be continuous with the flat surface. Here, the flat surface of the lower grindstone 9 is referred to as the grinding upper surface 12, and the flat surface of the upper grindstone 10 is referred to as the grinding lower surface 13.

  The material supplied through the opening 11 is introduced into the lower grindstone 9 and the upper grindstone 10, and is further fed between the grinding upper surface 12 and the grinding lower surface 13 by centrifugal force and pulverized. It flows out of the grindstone 10. Then, the pulverized material is accommodated in a container or the like (not shown) through a bowl-shaped discharge portion 14 provided in the apparatus main body 2.

  The apparatus main body 2 can rotate the lower grindstone 9 by the rotating means described above, and the lower grindstone 9 is moved up and down by the clearance adjusting means described below, so that the grinding upper surface 12 and the grinding lower surface 13 are moved. It is also possible to adjust the distance between the two.

  In the grinding machine 1 of the present embodiment, a servo motor 15 with a torque limiting function provided in a lateral direction, an output shaft 16 provided on the output shaft of the servo motor 15, and an outer peripheral side of the connecting member 6 are provided. A ring-shaped bevel gear 17 rotated by 16 is provided. Further, the bevel gear 17 is provided with a connecting pin 18 raised upward, and the connecting pin 18 is connected to a cylindrical support member 19 provided on the outer peripheral side of the connecting member 6. A bearing 20 that rotatably supports the spline shaft 7 is provided inside the support member 19. A cylindrical fixing member 21 that is cylindrical and fixed to the apparatus main body 2 is provided on the outer peripheral side of the support member 19. Although not shown, a male screw portion is provided on the outer peripheral surface of the support member 19, and a female screw portion that is screwed to the male screw portion is provided on the inner peripheral surface of the fixing member 21. As described above, the clearance adjusting means of the present embodiment includes the servo motor 15, the output shaft 16, the bevel gear 17, the connecting pin 18, the support member 19, the bearing 20, and the fixing member 21.

  When the main motor 4 is driven, the grinder 1 having such a configuration rotates the main shaft 5, the connecting member 6, the spline shaft 7, and the rotating disk 8, and can rotate the lower grindstone 9 accordingly. . When the servo motor 15 is driven, the bevel gear 17 is rotated by the output shaft 16, and thereby the support member 19 is also rotated through the connecting pin 18. Here, since the support member 19 is screwed to the fixing member 21, the support member 19 moves in the vertical direction with respect to the fixing member 21 while rotating, and is supported by the support member 19 via the bearing 20. The shaft 7 and the rotating disk 8 also move up and down. Thereby, the facing distance with the upper grindstone 10 can be adjusted by moving the lower grindstone 9 up and down.

  The attritor 1 includes a sensor 22 that can measure vibration or sound. In the present embodiment, a vibration sensor capable of measuring the frequency and amplitude level of vibration is provided in the vicinity of the upper grindstone 10 outside the upper lid 3. The vibration sensor can be provided inside the upper lid 3 or can be provided outside or inside the apparatus main body 2. When measuring sound, a sound sensor capable of measuring the frequency and amplitude level of sound is provided. In the case of employing a sound sensor, it can be provided outside or inside the upper lid 3 or the apparatus body 2 in the same manner as the vibration sensor.

  For such a sensor 22, the clearance adjusting means is configured to move the lower grindstone 9 up and down based on vibration or sound data obtained by the sensor 22.

  Further, the attritor 1 includes a temperature sensor 23 that is provided in the discharge unit 14 and measures the temperature of the pulverized material. In this embodiment, it is provided on the downstream side of the discharge portion 14 that is relatively far from the lower grindstone 9 and the upper grindstone 10, but may be provided on the upstream side of the discharge portion 14. Further, the temperature sensor 23 may be one that measures the temperature in contact with the flowing material, or one that measures without contact with the material.

  For such a temperature sensor 23, the clearance adjusting means is configured to move the lower grindstone 9 up and down based on the temperature data of the material obtained by the temperature sensor 23.

  Furthermore, the attritor 1 is configured by a control unit provided in the apparatus main body 2, for example, and includes an abnormality diagnosis unit capable of detecting an abnormality in the rotation unit and the clearance adjustment unit described above. The sensor 22 of the present embodiment measures the vibration or sound data generated in a state where the lower grindstone 9 is rotated in the initial stage of operation when the rotating means and the clearance adjusting means are not worn, and obtains initial data. It is possible to obtain time-lapse data by measuring after a predetermined long-term operation, and the abnormality diagnosis means compares the initial data with the time-lapse data, and when a predetermined deviation is recognized between the two It is possible to detect that an abnormality has occurred in the rotating means and the clearance adjusting means. Depending on the members included in these means, for example, characteristics may appear in the frequency and vibration level in the data. That is, the abnormality diagnosis means not only detects an abnormality without specifying the members included in the rotation means and the clearance adjustment means, but also detects an abnormality of a specific member by capturing characteristics that appear in the frequency and vibration level. Is also possible. In addition, a sensor different from the sensor 22 provided on the upper lid 3 is provided in the apparatus main body 2, and the rotation means and the clearance adjustment means are abnormal based on the initial data and temporal data of vibration or sound obtained by this sensor. May be detected.

  When the inventor of the present application repeatedly studied using such an attritor 1, the lower grindstone was rotated while being separated from the upper grindstone 10, and the lower grindstone was in contact with the upper grindstone 10. A difference was observed in the vibration or sound data obtained by the sensor 22 when the 9 was rotated. However, when it is attempted to detect a state in which the grinding upper surface 12 and the grinding lower surface 13 are slightly in contact with each other, the clearance is adjusted between the grinding upper surface 12 and the grinding lower surface 13 while supplying the material. In the state where the material is present, vibration and sound when the lower grindstone 9 is rotated vary depending on the type and state of the material, and may not be accurately detected. On the other hand, in a state where there is no material between the grinding upper surface 12 and the grinding lower surface 13, vibration and sound when the lower grindstone 9 is rotated are substantially constant, and the grinding upper surface 12 and the grinding lower surface 13. It was possible to detect a slight contact state with high accuracy.

  As a result of further studies, it has been found that the state in which the grinding upper surface 12 and the grinding lower surface 13 are slightly in contact can be detected with higher accuracy by paying attention to a specific frequency in the vibration or sound data obtained by the sensor 22. It was.

  This point will be described with reference to FIGS. FIG. 2 shows a vibration frequency and amplitude level data obtained by using a vibration sensor as the sensor 22 in accordance with the ascending position of the lower grindstone 9. FIG. 3 shows the sound frequency and vibration level data obtained by the sound sensor as the sensor 22 in accordance with the ascending position of the lower grindstone 9.

  As shown in FIG. 2, the difference in vibration level between the state where the lower grindstone 9 is separated from the upper grindstone 10 and the state where the lower grindstone 9 and the upper grindstone 10 are slightly in contact varies depending on the frequency of vibration. For example, although the difference in vibration level at 2.5 kHz is small, it becomes large at 10 kHz. Although the vibration level obtained by the measurement varies somewhat, if attention is paid to data of a frequency with a large difference in vibration level, the state where the lower grindstone 9 and the upper grindstone 10 are slightly in contact with each other without being affected by the variation is high. It can be detected with accuracy. In the present embodiment, a frequency band having a certain width is extracted, and clearance adjustment is performed based on the vibration level in this frequency band. For example, in the frequency band of 6.3 kHz to 20 kHz, the difference between the vibration level in a state where the lower grindstone 9 is separated from the upper grindstone 10 and the vibration level in a state where these are slightly in contact with each other is large. Therefore, by using data in the frequency band of 6.3 kHz to 20 kHz, it is possible to detect with high accuracy the state in which the lower grindstone 9 and the upper grindstone 10 are in slight contact. In particular, when the frequency band of the data to be used is 10 kHz to 20 kHz, the difference in vibration level is larger, so that it can be detected with higher accuracy.

  Even when using a sound sensor as shown in FIG. 3, the difference in vibration level between the state in which the lower grindstone 9 is separated from the upper grindstone 10 and the state in which the lower grindstone 9 and the upper grindstone 10 are slightly in contact with each other is There are differences depending on the frequency. In the state of FIG. 3, by using data in a frequency band of 2.5 kHz to 20 kHz, it is possible to detect a state in which the lower grindstone 9 and the upper grindstone 10 are in slight contact with high accuracy. In particular, when data in a frequency band of 6.3 kHz to 10 kHz having a large difference in vibration level and a large vibration level value is used, detection can be performed with higher accuracy.

  Based on such a study, the grinder 1 pulverizes the material by the following operation method.

  First, before supplying the material, the main motor 4 is driven in a state where the grinding upper surface 12 and the grinding lower surface 13 are separated from each other, and then the servo motor 15 is driven to raise the lower grindstone 9. While the lower grindstone 9 is raised, vibration or sound data is acquired by the sensor 22. In the present embodiment, a state in which the lower grindstone 9 and the upper grindstone 10 are in slight contact is detected based on the vibration level in the frequency band of 6.3 kHz to 20 kHz among the data obtained by the vibration sensor. And the clearance adjustment of the grinding upper surface 12 and the grinding lower surface 13 is performed so that it may become the optimal value according to the kind and state of a material on the basis of the position of the lower grindstone 9 at this time. In the present embodiment, the torque limiting function of the servo motor 15 restricts the lower grindstone 9 from rising excessively. For this reason, for example, even when the sensor 22 has a problem or when valid data cannot be acquired, it is possible to reliably prevent a problem that the lower grindstone 9 is strongly pressed against the upper grindstone 10 and is damaged. . Thereafter, the material is supplied, and the material is pulverized by the lower grindstone 9 and the upper grindstone 10.

  In addition, after grinding | pulverization of material is started, since the grindstone and the apparatus are thermally expanded by the temperature of material and the frictional heat at the time of grinding | pulverization, the clearance between the grinding upper surface 12 and the grinding lower surface 13 will fluctuate. Also, the clearance changes depending on the abrasion of the grindstone surface. For this reason, the clearance adjustment is performed at a predetermined timing even during the operation. To adjust the clearance during the operation, first, the material supply is stopped, and then the servo motor 15 is driven to lower the lower grindstone 9. During this time, the driving of the main motor 4 is continued and the lower grindstone 9 is rotated. Thereby, the material remaining on the lower grindstone 9 and the upper grindstone 10 is discharged by the centrifugal force of the lower grindstone 9, so that the grinding upper surface 12 and the grinding lower surface 13 are in a state where no material exists. That is, it is possible to detect a state in which the lower grindstone 9 and the upper grindstone 10 are in slight contact with high accuracy. Thereafter, the servo motor 15 is driven in the reverse direction to raise the lower grindstone 9, and the clearance between the grinding upper surface 12 and the grinding lower surface 13 is adjusted in the same manner as the procedure before starting the operation described above. Restart supply.

  In the present embodiment, a temperature sensor 23 is provided. For example, when the clearance between the grinding upper surface 12 and the grinding lower surface 13 becomes narrow due to thermal expansion, the temperature of the pulverized material increases due to friction. When the temperature of the material obtained by the temperature sensor 23 rises and deviates from a predetermined value, the servo motor 15 is driven to lower the lower grindstone 9 and the clearance adjustment is performed so as to be within the predetermined temperature. In addition, when the temperature of the material obtained by the temperature sensor 23 is low, the clearance adjustment may be performed so that the clearance between the grinding upper surface 12 and the grinding lower surface 13 becomes narrow. Also, when the clearance adjustment by the temperature sensor 23 is performed, the sensor 22 is used to temporarily stop the material supply and detect again the state where the lower whetstone 9 and the upper whetstone 10 are slightly in contact with each other, and the intended clearance. You may adjust so that it becomes.

  Further, if the operation is continued for a long period of time, various members included in the rotating means and the clearance adjusting means may be worn and affect the accuracy of the clearance between the grinding upper surface 12 and the grinding lower surface 13. Although the worn member needs to be replaced, in the present embodiment, the abnormality diagnosis unit described above can detect the abnormality of the rotation unit and the clearance adjustment unit, and can prompt replacement at an optimal timing. In this case, first, the sensor 22 measures the vibration or sound data generated when the lower grindstone 9 is rotated in the initial stage of operation when various members included in these means are not worn to obtain initial data. Keep it. Further, time-dependent data that is data after driving for a relatively long period of time is also acquired as needed. Then, the abnormality diagnosis means compares the initial data with the time-lapse data, and the abnormality of the rotation means and the clearance adjustment means can be detected depending on whether or not there is a predetermined difference between the two. Even when comparing the initial data and the time-lapse data, it is preferable to perform the comparison based on the data of the specific frequency included in these data. In addition, some members included in these means may exhibit characteristics in the frequency and vibration level in the data. For this reason, it is also possible to detect that an abnormality has occurred in a specific member by capturing this feature.

  The attritor of the present invention is not limited to the above-described embodiment, and includes those in which various modifications and additions are made within the scope of the claims. For example, although the above-described upper grindstone 10 is attached so as not to rotate with respect to the upper lid 3, the upper grindstone 10 may be provided so as to be rotatable by another motor provided separately from the main motor 4.

  Further, the clearance adjusting means of the present embodiment moves the lower grindstone 9 up and down by the servo motor 15, but a manual handle may be provided to move the lower grindstone 9 up and down. In this case, as one of the clearance adjusting means, when a state where the grinding upper surface 12 and the grinding lower surface 13 are slightly in contact with each other is detected from the data obtained by the sensor 22, it is notified by sound, a lamp, an image, or the like. The presentation means which can do is provided. Thereby, even when the adjuster moves the handle to move the lower grindstone 9 up and down, the reference position of the lower grindstone 9 can be accurately grasped by the sound from the presentation means. And the opposing distance of the grinding | polishing upper surface 12 and the grinding | polishing lower surface 13 can be adjusted appropriately by moving a handle | steering-wheel based on the rotation amount of the steering wheel grasped | ascertained beforehand, and the up-down direction movement amount of the lower grindstone 9. . In the case of using the temperature sensor 23, it is preferable to provide the presenting means with a function for notifying whether or not the pulverized material is within the optimum temperature.

  In addition, the grinder is connected to a wired or wireless network so that the data obtained by the various sensors described above can be received at a remote location, and clearance control of the grinder and software update are performed from a remote location. It is also possible to provide a function for grasping the state of the grinder.

1: grinding machine 2: apparatus main body 3: upper lid 4: main motor 5: main shaft 6: connecting member 7: spline shaft 8: rotating disk 9: lower grinding wheel 10: upper grinding wheel 11: opening 12: grinding upper surface 13: grinding Lower surface 14: Discharge unit 15: Servo motor 16: Output shaft 17: Gear 18: Connection pin 19: Support member 20: Bearing 21: Fixed member 22: Sensor (vibration sensor, sound sensor)
23: Temperature sensor

Claims (4)

An apparatus main body provided with a ring-shaped lower grindstone provided rotatably and vertically movable; an upper lid provided with a ring-shaped upper grindstone provided so as to be openable and closable with respect to the apparatus main body; Adjusting the facing distance between the grinding surface of the lower grinding wheel and the grinding surface of the upper grinding wheel by moving the lower grinding wheel up and down, and a sensor for measuring vibration or sound during operation provided on the main body or the upper lid In a grinder provided with a clearance adjusting means,
The sensor acquires vibration or sound data that is generated when the lower grindstone is rotated and the material to be crushed does not exist on the grinding upper surface and the grinding lower surface.
The said clearance adjustment means is a grinder which can move the said lower whetstone up and down based on the said data for adjustment of the said opposing distance.   The attritor according to claim 1, wherein the clearance adjusting means is capable of moving the lower grindstone up and down based on data at a specific frequency included in the data.   The apparatus main body or the upper lid includes a discharge unit that discharges the material crushed by the lower grindstone and the upper grindstone, and the discharge unit includes a temperature sensor that measures the temperature of the crushed material, The attritor according to claim 1 or 2, wherein the clearance adjusting means can move the lower grindstone up and down based on temperature data of the material obtained by the temperature sensor. An apparatus main body provided with a ring-shaped lower grindstone provided rotatably and vertically movable; an upper lid provided with a ring-shaped upper grindstone provided so as to be openable and closable with respect to the apparatus main body; Adjusting the facing distance between the grinding surface of the lower grinding wheel and the grinding surface of the upper grinding wheel by moving the lower grinding wheel up and down, and a sensor for measuring vibration or sound during operation provided on the main body or the upper lid In a grinder provided with a clearance adjusting means,
The apparatus main body has a rotating means for rotating the lower grindstone,
The sensor is a vibration or sound generated in a state where the lower grindstone is rotated, acquires initial data by measuring in an initial stage of operation, and acquires time-lapse data by measuring after a predetermined time of operation,
Furthermore, an attritor comprising an abnormality diagnosing unit that compares the initial data with the time-lapse data and detects an abnormality of the rotating unit and the clearance adjusting unit.

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