JP6051280B2 - Grinder - Google Patents

Description

  The present invention relates to a grinding machine for grinding aggregates and the like, and particularly relates to noise reduction measures.

Conventionally, various ball mill type grinders exist as apparatuses for obtaining recycled aggregates from concrete and asphalt waste.
Among them, many have a structure in which the drum body is partitioned by a plurality of partition plates in order to increase the residence time of the material to be ground. In a grinder having such a structure, the material to be ground is partitioned. While moving from one end side of the drum body to the other end side through the gap between the peripheral edge of the plate and the drum body wall, the balls are ground by balls (grinding media) in each section.

By the way, in such a conventional attritor, since the partition plate is attached so as to be orthogonal to the central axis, the ball can be positively moved in the front-rear direction (axial length direction of the drum body). The ball motion was mostly in the radial and circumferential directions.
For this reason, a so-called co-rotation phenomenon occurs in which the ball and the material to be ground rotate at a constant speed, which has caused a significant reduction in grinding efficiency.

In order to solve such a problem, the present applicant has already proposed a grinding machine capable of preventing the above-mentioned phenomenon of co-rotation and greatly improving the grinding efficiency (the following patent document). 1 and 2).
In the inventions described in Patent Documents 1 and 2, it is possible to positively impart a back-and-forth motion to the grinding medium (ball or the like) by attaching the partition plate to the surface orthogonal to the central axis. In other words, the partition plate has a function as a stirring blade.

However, the conventional ball mill type grinder including the grinders described in Patent Documents 1 and 2 has a problem of generating a large noise.
As a result of investigation by the present applicant, it has been found that the main cause of noise is the collision between the ball or the object to be ground and the drum body, and in particular, the volume of noise due to the collision between the ball and the drum body is high.
Therefore, in order to effectively reduce the collision noise with the partition plate, for example, it is conceivable to reduce the number of grinding media. However, if the number of grinding media is reduced, the contact between the grinding object and the grinding media is possible. Since the number of times decreases, there arises a problem that the grinding efficiency decreases.

JP 2008-104910 A JP 2010-125446 A

  The present invention has been made to solve the above-mentioned problems of the prior art, and reduces the noise by eliminating the grinding media without lowering the grinding efficiency, and hence the downsizing of the apparatus. The purpose is to provide a grinder that can contribute to the improvement of processing capacity.

The attritor according to the first aspect of the present invention is an attritor not using a friction medium,
A cylindrical drum body configured to be able to discharge the ground material taken from one part from the other part,
A central axis that penetrates the drum body in the cylinder length direction;
A plurality of partition plates attached to the central axis at predetermined intervals in the axial direction, and partitioning the internal space of the drum body into a plurality of grinding chambers;
A plurality of friction plates attached to the drum body and respectively facing the partition plates;
A hopper for charging the material to be ground is provided at the center of the drum body,
First and second sieve members attached to the left and right sides of the drum body, for separating the ground material discharged from the drum body into a plurality of grades,
First and second discharge hoppers, first and second sieve members, and first and second motors, respectively, on the left and right sides of the drum body,
A sieve rotation axis for rotating the first sieve member, the sieve rotation axis separated from the central axis;
The central shaft and the sieve rotation shaft are supported by a bearing member so as to be relatively rotatable, and are respectively connected to one of the first and second motors.

In the grinding machine according to the first aspect, the sieving rotary shaft rotates integrally with the central shaft.

The attritor according to the second aspect of the present invention is an attritor not using a friction medium,
A cylindrical drum body composed of a combination of semi-cylindrical drum bodies, configured to be able to discharge the ground material taken from a part from the other part,
A central axis that penetrates the drum body in the cylinder length direction;
A plurality of partition plates attached to the central axis at predetermined intervals in the axial direction, and partitioning the internal space of the drum body into a plurality of grinding chambers;
A plurality of friction plates attached to the drum body and opposed to the partition plates, respectively, wherein the center is spaced apart from an inner peripheral portion disposed at the center of each of the plurality of friction plates. Comprising a plurality of friction plates inserted through the shaft, whereby the partition plate and the friction plate rotate in the opposite directions,
A grinder characterized by that.

  The attritor according to the first aspect of the present invention includes a cylindrical drum body configured to be able to discharge a ground material taken from a part from another part, and the drum body in the cylinder length direction. A central axis that penetrates, a plurality of partition plates that are attached to the central axis at predetermined intervals in the axial direction, and that divide the internal space of the drum body into a plurality of grinding chambers; A plurality of friction plates respectively facing the partition plate and a hopper for feeding the material to be ground are provided at the center of the drum body, attached to the left and right sides of the drum body, and the ground material discharged from the drum body First and second sieving members that are classified into a plurality of grades, and first and second discharge hoppers, first and second sieving members, and first and second motors on the left and right sides of the drum body, respectively. And rotating the first sieve member And a sieve rotation shaft separated from the central axis. The central axis and the sieve rotation shaft are relatively rotatably supported by bearing members, respectively. And the second motor are connected to each other, so that the raw material is fed from the center of the drum body and discharged from the left and right sieve members (first and second sieve members). Capability can be increased by a factor of about 2.

  The attritor according to the second aspect of the present invention is configured to be able to discharge the ground material taken from a part from the other part, and a cylindrical drum body formed by combining a semicylindrical drum body and A central axis that penetrates the drum body in the cylinder length direction, and a plurality of partition plates that are attached to the central axis at predetermined intervals in the axial direction and divide the internal space of the drum body into a plurality of grinding chambers; A plurality of friction plates attached to the drum body and opposed to the partition plates, respectively, wherein the center is spaced apart from an inner peripheral portion disposed at the center of each of the plurality of friction plates. It is provided with a plurality of friction plates formed by inserting shafts, whereby the partition plate and the friction plate rotate in opposite directions relatively. The frictional force acting on the material to be crushed Since increased, thereby improving the milling 砕効 rate.

It is a partial section front view of the attrition machine concerning the embodiment of the present invention. It is a figure which shows the friction board which concerns on embodiment, Comprising: (a) is a top view, (b) is sectional drawing in the IIb-IIb line | wire. It is a figure which shows the partition plate which concerns on embodiment, Comprising: (a) is a top view, (b) is a side view, (c) is sectional drawing in the IIIc-IIIc line. It is a partial section front of a sieve member and a conveyor device concerning an embodiment. It is sectional drawing which shows the 1st modification of a friction board. It is sectional drawing for demonstrating the grinding action by a friction plate and a partition plate. It is a figure which shows the 2nd modification of a friction board, Comprising: (a) is a perspective view of one piece, (b) is a perspective view of the state which match | combined two pieces. It is a figure which shows the 3rd modification of a friction board, Comprising: (a) is a perspective view of one piece, (b) is a perspective view of the state which match | combined two pieces. It is a figure which shows the 4th modification of a friction board, Comprising: (a) is a perspective view of one piece, (b) is a perspective view of the state which match | combined two pieces. It is a fragmentary sectional front view of the grinder which concerns on the modification of whole structure.

Hereinafter, an embodiment of a grinder according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a partial sectional front view of a grinder according to an embodiment of the present invention.
The attritor according to the embodiment of the present invention is configured to be able to take a ground material (raw material) from a part (hopper (71)) into the inside and discharge it from the other part (discharge hopper (21)). The cylindrical drum body (1), the central axis (2) penetrating the drum body (1) in the cylinder length direction, and the drum body (1) are attached at predetermined intervals in the length direction of the central axis (2). 1) a plurality of partition plates (4) partitioning the internal space into a plurality of grinding chambers (6), a friction plate (5) attached to the drum body (1) and facing the partition plate (4); It has.
A sieve member (22) that rotates together with the central shaft (2) is attached to the downstream side of the discharge hopper (21).
Both ends of the central shaft (2) are supported by a pair of bearing members (16) and (17).
A motor (M) serving as a drive source for rotating the central shaft (2) is connected to one end portion (upstream side) of the central shaft (2), and a sieve member (22) is connected to the other end portion (downstream side). ) Is attached. The sieving member (22) has a cylindrical shape having a taper that gradually becomes larger in diameter as it is separated from the drum body (1).

The drum body (1) has a substantially cylindrical shape by combining two upper and lower semi-cylindrical members.
The plurality of partition plates (4) are provided at regular intervals in the axial direction of the central axis, and divide the interior of the drum body (1) into a plurality of grinding chambers (6) in the axial length direction. Each partition plate (4) is inclined with respect to a plane orthogonal to the central axis (2) and is substantially parallel to each other. Each grinding chamber (6) has no grinding media (such as balls).
The plurality of friction plates (5) are arranged in each grinding chamber (6) and are orthogonal to the central axis (2).
In the grinding machine of the present embodiment, the ground material (a) is supplied from the hopper (71) together with the water (b) and sequentially passes through each grinding chamber (6), and then the outermost part of the drum body (1). It is discharged from the discharge hopper (21) on the downstream side and sent to the sieving member (22).
However, instead of such a wet structure, a dry structure in which the material to be ground (a) is sent by a blower may be adopted.

3A and 3B are diagrams showing the partition plate according to the present embodiment, in which FIG. 3A is a plan view, FIG. 3B is a side view, and FIG. 3C is a cross-sectional view taken along line IIIc-IIIc.
The partition plate (4) has a substantially circular structure in which two semicircular curved plates are combined, and the central axis (2) is inserted through the central hole (41). The partition plate (4) is attached to be inclined clockwise from a plane orthogonal to the central axis (2).
Even when the inclination direction of the partition plate (4) is opposite to that of the present embodiment, the material to be ground (a) is moved by water flow (in the case of a wet type) or air flow (in the case of a dry type). There is no problem with the grinding process.
The partition plate (4) is provided with a plurality of partial arc-shaped through holes (42) arranged concentrically. The circular arc width of the through hole (42) is set to a size that allows only the object to be ground (a) ground to be less than a predetermined particle diameter. The arc width of the through hole (42) may gradually decrease from the upstream partition plate (4) of the drum body (1) toward the downstream partition plate (4).

Further, as shown in FIGS. 3B and 3C, the surface of the partition plate (4) is provided with a hemispherical convex portion (43), and a large concave-convex pattern is formed. Due to the presence of such a large concavo-convex pattern, when the crushed object (a) collides with the partition plate (4) from an oblique direction, the surface of the partition plate (4) slips slightly, and then the convex portion (43). Thus, the grinding efficiency of the material to be ground (a) is increased.
Moreover, only the convex part (43) of a partition plate (4) can be comprised with a especially hard material (for example, cemented carbide), the wear of a partition plate (4) can be reduced, and a lifetime can also be extended.
In addition, it may replace with a convex part (43) and you may form the uneven | corrugated pattern which provided the comparatively big recessed part. In this case, the same effect as that of the concave / convex pattern provided with the convex portions (43) can be obtained.

  In FIG. 1, the partition plate (4) is shown in a flat plate shape for easy viewing. However, as shown in FIG. 3, the partition plate (4) in the present embodiment is spaced at regular intervals in the circumferential direction. It has a curved surface structure in which the peaks and valleys are repeated. However, the partition plate (4) may have a planar structure. Further, the partition plate (4) as a whole may be an elliptical plate instead of a disc. Moreover, you may employ | adopt the same curved surface structure with respect to the friction plate (5) mentioned later.

2A and 2B are diagrams illustrating the friction plate according to the present embodiment, in which FIG. 2A is a plan view and FIG. 2B is a cross-sectional view taken along the line IIb-IIb.
The friction plate (5) is divided into two parts corresponding to the semi-cylindrical drum body (1). The friction plate (5) is divided into two parts, a semi-disc part (50) and a semi-disc part ( 50) and a flange portion (54) surrounding the outer peripheral side.
In the semicircular plate portion (50), a semicircular inner edge peripheral portion (51) is formed at a position corresponding to the center portion of the combination of the two friction plates (5), and the inner edge peripheral portion (51). Faces the central axis (2) with a predetermined gap.
The friction plate (5) is attached to the drum body (1) with screws (not shown) in a state where the outer peripheral portion (53) of the semi-cylindrical flange portion (54) is in contact with the inner wall of the drum body (1). It is attached. The flange portion (54) is provided with a screw insertion hole (55).

For the sake of clarity, the display in the cross section of the friction plate (5) in FIG. 1 is omitted, but the semicircular plate portion (50) of the friction plate (5) has many partial circles arranged concentrically. An arc-shaped through hole (52) is formed. The circular arc width of the through hole (52) is set to a size that allows only the material to be ground (a) ground to be less than a predetermined particle size in the grinding chamber (6). The arc width of the through hole (52) may gradually decrease from the upstream friction plate (5) of the drum body (1) toward the downstream friction plate (5).
In addition, the semicircular disk portion (50) and the flange portion (54) of the friction plate (5) are finely formed by casting, press molding or the like as shown in the partial enlarged view of FIG. An uneven pattern (57) is provided.
In addition, although the friction plate (5) in this embodiment has a flat plate structure, the friction plate (5) may have a curved plate structure like the modified example demonstrated later. Further, the friction plate (5) may be an elliptical plate instead of a circular plate as a whole.

At least one of the partition plate (4) and the friction plate (5) may be rotated, but in this embodiment, the drum body (1) is fixed and the central shaft (2) is rotated. ing.
Therefore, in the present embodiment, the central axis (2) rotates and the partition plate (4) attached to the central axis (2) rotates, while the friction plate (5) attached to the drum body (1) It is stationary.

FIG. 6 is a cross-sectional view for explaining the grinding action by the friction plate and the partition plate.
As shown in the figure, when the partition plate (4) is rotated by 180 ° from the solid line position shown in FIG. 6, the partition plate (4) is in the position shown by the broken line in FIG. . Meanwhile, in the narrow region (Rm) where the partition plate (4) and the friction plate (5) approach each other, the ground material (a) is strongly pressed between the partition plate (4) and the friction plate (5). At the same time, it receives a frictional force due to the rotational force of the partition plate (4). As a result, the material to be ground (a) is rubbed against the friction plate (5) or the partition plate (4), or is rubbed between the materials to be ground (a) to adhere to the surface of the material to be ground (a). Foreign matter such as cement is removed efficiently.
The material to be ground (a) includes the through holes (42) and (52) of the partition plate (4) and the friction plate (5), and the clearance between the friction plate (5) and the central axis (2) (Sp1). It passes through the gap (Sp2) between the partition plate (4) and the drum body (1), and is sent to the downstream side together with water (b).
At this time, since the action of scraping off the foreign matter can be obtained also by the edges of the numerous through holes (42) and (52) provided in the partition plate (4) and the friction plate (5), the foreign matter is more effectively removed. Can be removed.

The structure of the attritor of the present invention is not limited to the structure shown in FIG.
For example, only the friction plate (5) may be rotated to fix the partition plate (4).
In this case, only the drum body (1) is rotated, but the drum medium (1), the partition plate (4), friction, and the like are caused by the centrifugal force that the grinding medium (a) receives from the rotation of the drum body (1). Even a strong collision with the plate (5) does not produce a loud noise like a collision between the drum body (1) and the grinding medium. Moreover, since a large centrifugal force can be applied to the material to be ground (a) by the rotation of the drum body (1), the collision between the material to be ground (a) and the flange portion (54) of the friction plate (5). Milling efficiency is increased.
Moreover, you may rotate both a partition plate (4) and a friction plate (5) in a reverse direction relatively.
In that case, since the frictional force which acts on the to-be-ground material (a) pinched | interposed between the partition plate (4) and the friction plate (5) is raised more, grinding efficiency can be improved.

FIG. 5 is a cross-sectional view showing a first modification of the friction plate (5).
In the friction plate (5) according to the first modification, the flange portion (54) is provided wider than that shown in FIG. 2 (b), and extends to the middle point of each grinding chamber (6), for example. ing. Thus, by making the flange portion (54) wide, the area of the inner side surface of the flange portion (54) with which the object to be ground (a) collides increases, so that the grinding efficiency can be increased. .

Further, as shown in the partially enlarged view of FIG. 5, the fine uneven pattern (57) formed by sandblasting or the like on the surface of the semicircular plate portion (50) or the flange portion (54) of the friction plate (5). Is formed.
When the object to be ground (a) collides with the surface of the friction plate (5) from an oblique direction by the fine uneven pattern (57) shown in FIG. The probability of being rubbed strongly without slipping increases. Therefore, providing the fine uneven pattern (57) on the friction plate (59) can further improve the grinding efficiency of the material to be ground (a).
Although not shown in FIG. 3, the partition plate (4) may also be provided with a fine uneven pattern to further improve the grinding efficiency of the material to be ground (a).
However, it is not always necessary to provide a fine uneven pattern in both the partition plate (4) and the friction plate (5).
Although not shown in FIGS. 2B and 5, the friction plate 5 may be formed with a convex portion such as the partition plate 4 or a large concave-convex pattern with the concave portion ( (Refer to a modified example described later).
Even in that case, the above-described effects can be obtained.

  The constituent materials of the partition plate (4) and the friction plate (5) are not limited, but general-purpose steel materials, high hardness steel materials such as alloy steel, cemented carbide, ceramics, metal-ceramic materials, and so on. In order to increase the grinding efficiency or extend the service life, a material with higher hardness is preferred. Only a part of the partition plate (4) and the friction plate (5) made of a general-purpose steel material may be made of a high-hardness material, for example, by coating the surface with a high-hardness material.

FIG. 4 is a partial sectional front view of the sieving member and the conveyor device according to the present embodiment.
Below the sieving member (22), a guide member (82) for receiving a relatively small-diameter ground material (a1) passing through the mesh of the sieving member (22), and a lower part of the guiding member (82) are arranged. A first feeding device (8) is arranged. A first conveyor member (81) for sending the material to be ground (a1) to the rear of the paper surface of FIG. 4 is attached to the first feeding device (9).
In addition, a second feeding device (9) for receiving a relatively large-diameter ground material (a2) sent without passing through the mesh of the sieve member (22) is disposed on the downstream side of the sieve member (22). Has been.
A second conveyor member (91) for sending the material to be ground (a1) to the front of the paper surface of FIG. 4 is attached to the second feeding device (9).

As in the present embodiment, a sieving member (22) is provided at the downstream end of the grinder, and the ground material to be ground is separated into sizes corresponding to the intended use, so that it is continuous with the grinding process. Thus, the separation step can be performed, and the overall efficiency can be improved.
The mesh size of the sieving member (22) can be arbitrarily selected according to the type of aggregate to be finally obtained. For example, when separating into gravel and sand, for example, a mesh having a size of about 5 mm can be adopted.
The material of the sieving member (22) is not particularly limited, but generally punched metal (steel plate) is used.

Moreover, like this Embodiment, by arrange | positioning the conveyor members (81) and (91) which each convey a to-be-ground material (a1) and (a2), the to-be-ground material (a1) and (a2) which were separated. ) Can be arranged without interfering with the attritor.
Note that the number of sieve members may be two or more, and three or more conveyor members (feeding devices) may be arranged accordingly.

Next, a further modification of the friction plate (5) will be described.
7A and 7B are diagrams showing a second modification of the friction plate, in which FIG. 7A is a perspective view of one piece, and FIG. 7B is a perspective view of a state in which the two pieces are combined.
The friction plate (5) which concerns on a 2nd modification has the semicircular disk part (50) similar to the partition plate (4) shown in FIG. That is, the semicircular disk part (50) is formed of a curved surface inclined with respect to a plane orthogonal to the central axis (2), and the semicircular disk part (50) has a large number of convex parts (56 concentrically arranged). ) (Concave / convex pattern) and a plurality of concentric circularly arranged through holes (52) are provided, and the inner peripheral edge (51) faces the central axis (2) with a predetermined gap therebetween. .
The circular arc width of the through hole (52) is set to a size that allows only the material to be ground (a) ground to be less than a predetermined particle size.
The flange portion (54) is provided wide like the first modified example, and the friction plate (5) is in a state where the outer peripheral portion (53) of the flange portion (54) is in contact with the drum body (1). Is attached to the drum body (1).

  Thus, when using the friction plate (5) in which the semicircular disk part (50) is inclined with respect to the plane orthogonal to the central axis (2), the partition plate (4) is orthogonal to the central axis (2). Preferably it is. Although the partition plate (4) may have a planar structure or a curved surface structure, for example, a partition plate (4) having substantially the same shape as the semicircular plate portion (50) of the friction plate (5) shown in FIG. 2 can be used. .

FIGS. 8A and 8B are views showing a third modification of the friction plate, in which FIG. 8A is a perspective view of one piece, and FIG. 8B is a perspective view of a state in which two pieces are combined.
The friction plate (5) according to the third modification has a semicircular plate portion (50) orthogonal to the central axis (2). The semicircular disk portion (50) is provided with a large number of concentric convex portions (56) (concave / convex pattern) and a large number of concentric circular arc-shaped through holes (52). The inner periphery (51) faces the central axis (2) with a predetermined gap.
The circular arc width of the through hole (52) is set to a size that allows only the material to be ground (a) ground to be less than a predetermined particle size.
The flange portion (54) is provided wide like the first modified example, and the friction plate (5) is in a state where the outer peripheral portion (53) of the flange portion (54) is in contact with the drum body (1). Is attached to the drum body (1).

  Thus, when using the friction plate (5) in which the semicircular disk part (50) is inclined from the central axis (2), it is preferable that the partition plate (4) is inclined with respect to the central axis (2). The partition plate (4) may have a planar structure or a curved structure.

FIGS. 9A and 9B are diagrams showing a fourth modification of the friction plate, where FIG. 9A is a perspective view of one piece, and FIG. 9B is a perspective view of a state in which two pieces are combined.
The friction plate (5) according to the fourth modification has a semicircular plate portion (50) and a flange portion (54) having substantially the same shape as the friction plate (5) according to the second modification shown in FIG. Yes.
The friction plate (5) according to the fourth modified example is different from the friction plate (5) according to the second modified example in that the semicircular plate portion (50) is inclined with respect to the plane orthogonal to the central axis (2). The direction of being is the opposite.
That is, the friction plate (5) according to the second modification is inclined clockwise from the plane orthogonal to the center axis (2), whereas the friction plate (5) according to the fourth modification is the center axis (2 ) Tilted counterclockwise from the plane perpendicular to.
Regardless of whether the direction of inclination of the friction plate (5) is the second modified example or the fourth modified example, the movement of the material to be ground (a) is a water flow (when wet) or an air flow (when dry). Therefore, there is no problem in the grinding process.
Also when using the friction plate (5) which concerns on a 4th modification, it is preferable that a partition plate (4) is orthogonal to a central axis (2). Although the partition plate (4) may have a planar structure or a curved surface structure, for example, a partition plate (4) having substantially the same shape as the semicircular plate portion (50) of the friction plate (5) shown in FIG. 2 can be used. .

As can be easily understood from the modifications described above, the structures and materials of the partition plate (4) and the semicircular plate portion (50) of the friction plate (5) may be the same. In addition, whether the partition plate (4) and the semicircular plate portion (50) of the friction plate (5) are orthogonal to the central axis (2) or inclined from the orthogonal plane is adopted alternately. Or both may be inclined.
Moreover, although both do not need to incline, it is preferable that the narrow area | region (Rm) which pinches | interposes a to-be-ground material (a) exists at least between a partition plate (4) and a friction plate (5). .

Next, a modified example of the overall structure of the attritor will be described.
FIG. 10 is a partial cross-sectional front view of a grinder according to a modification of the overall structure.
As shown in the figure, the attritor according to this modification is provided with a hopper (71) for charging the material to be ground (raw material) at the center of the drum body (1), and on the left and right sides of the drum body (1), A discharge hopper (21), a sieve member (22), and a motor (M) are provided.
In addition, in order to rotate one (right side in the figure) of the sieve member (22), a sieve rotary shaft (2a) separated from the central axis (2) is provided, and the central axis (2) and the sieve rotary shaft are provided. (2a) is supported relatively rotatably by a bearing member (18).
The motor (M) is connected to both end portions of the central shaft (2), and the left and right sieve members (22) are rotated together with the central shaft (2) by rotating the left and right motors (M) in synchronization. It is good also as a structure to make. In this case, the central axis (2) and the sieve rotation axis (2a) are integrated.
According to the structure of this modified example, the raw material is introduced from the center of the drum body (1) and discharged from the left and right sieving members (22), so that the processing capacity can be greatly improved (about twice). it can.

The attritor according to the present invention is used, for example, to obtain recycled aggregate from concrete waste or asphalt waste.

a ground material b water 1 drum body 2 center shaft 22 sieve member 4 partition plate 41 center hole

42 Through-hole 5 Friction plate 50 Semi-disc portion 51 Inner peripheral edge portion 52 Through-hole 54 Flange portion 6 Grinding chamber 8 First feed device 81 First conveyor device 9 Second feed device 91 Second conveyor device

Claims (2)

A mill that does not use friction media,
A cylindrical drum body configured to be able to discharge the ground material taken from one part from the other part,
A central axis that penetrates the drum body in the cylinder length direction;
A plurality of partition plates attached to the central axis at predetermined intervals in the axial direction, and partitioning the internal space of the drum body into a plurality of grinding chambers;
A plurality of friction plates attached to the drum body and respectively facing the partition plates;
A hopper for charging the material to be ground is provided at the center of the drum body,
First and second sieve members attached to the left and right sides of the drum body, for separating the ground material discharged from the drum body into a plurality of grades,
First and second discharge hoppers, first and second sieve members, and first and second motors, respectively, on the left and right sides of the drum body,
A sieve rotation axis for rotating the first sieve member, the sieve rotation axis separated from the central axis;
The center shaft and the screen rotation shaft are rotatably supported by a bearing member, and are connected to either the first motor or the second motor, respectively. 2. The attritor according to claim 1, wherein the sieve rotation shaft is rotated integrally with the central shaft.