JP7714487B2 - Discharge device, crushing device, and method for operating the crushing device - Google Patents

Description

This disclosure relates to an ejection device, a crushing device, and a method for operating the crushing device.

Inside the mill, the powdered raw material is blown upward by the carrier gas supplied from the outer periphery of the grinding table. Collisions of the blown-up powder with the shafts of the grinding rollers located above the outer periphery of the grinding table and the roller supports that support the grinding rollers cause wear, making countermeasures for wear in these areas an issue. Patent Document 1 discloses that by covering the areas that are hit by the carrier gas blown out from the outlet with a shield, wear on the grinding rollers caused by the pulverized fuel blown up by the carrier gas is reduced. Patent Document 1 also teaches that to prevent the pulverized fuel blown up by the carrier gas from accumulating on the inner surface of the shield, the inner surface of the shield is inclined at an angle greater than the angle of repose of the pulverized fuel, promoting the discharge of the pulverized fuel.

Patent No. 6779009

However, if powder with a relatively large particle size enters the space formed between the grinding roller and the shield from above, the powder cannot be expelled from the space and instead accumulates on the inner surface of the shield. This occurs because powder with a particle size larger than the gap formed between the grinding roller and the shield cannot pass through the gap, even if the shield is inclined at an angle greater than the angle of repose of the powder.

When powder accumulates on the inner surface of the shield, it enters the space formed between the crushing roller and the shield, preventing it from being smoothly discharged, and becomes a starting point for the powder to accumulate on the inner surface of the shield. Furthermore, when the crushing roller rotates with powder accumulated on the inner surface of the shield, the powder is constantly stirred up within the space, and collisions and friction with the powder cause wear on the inner surfaces of the crushing roller and shield.

This disclosure was made in light of these circumstances, and aims to provide a discharge device, a crusher, and a method of operating a crusher that can prevent crushed material from accumulating in the space formed between the crusher roller and a protective member that protects the crusher roller unit from crushed material transported by the carrier gas, thereby preventing wear on the inner surfaces of the crusher roller and protective member.

In order to solve the above problems, the present disclosure employs the following means.
A discharge device according to one aspect of the present disclosure is a discharge device attached to a crushing device that crushes raw materials, the crushing device comprising: a crushing table; a crushing roller unit that crushes the raw materials supplied to the crushing table from a raw material supply unit between the crushing table and the crushing roller unit; and an outlet that is provided on the outer periphery of the crushing table and blows out a conveying gas upward. The crushing roller unit has a journal head attached to a housing, a journal shaft that is supported by the journal head and extends along an axis, and a crushing roller attached to the journal shaft so as to be rotatable around the axis. The discharge device comprises: a protective member that surrounds the lower part of the journal shaft at a position where the journal head and the crushing roller are adjacent to each other and protects the crushing roller unit from crushed material produced by crushing the raw materials transported by the conveying gas; and a discharge section that rotates around the axis and discharges the crushed material that has entered the space formed between the crushing roller and the protective member to the outside of the space.

A method for operating a crushing device according to one aspect of the present disclosure is a method for operating a crushing device that crushes raw materials, the method comprising: a crushing table; a crushing roller unit that crushes the raw materials supplied to the crushing table from a raw material supply unit between the crushing table and the crushing roller unit; and an outlet provided on the outer periphery of the crushing table and that blows a conveying gas upward; the crushing roller unit having a journal head attached to a housing; a journal shaft supported by the journal head and extending along an axis; a crushing roller attached to the journal shaft so as to be rotatable about the axis; and a protective member that surrounds a lower portion of the journal shaft at a position adjacent to the journal head and the crushing roller and protects the crushing roller unit from crushed material produced by crushing the raw materials and transported by the conveying gas; and a discharge step of rotating a discharge unit about the axis to discharge crushed material that has entered a space formed between the crushing roller and the protective member to the outside of the space.

This disclosure provides a discharge device, a crusher, and a method for operating a crusher that can prevent crushed material from accumulating in the space formed between the crusher roller and a protective member that protects the crusher roller unit from crushed material transported by the carrier gas, and prevent wear on the inner surfaces of the crusher roller and protective member.

FIG. 2 is a vertical cross-sectional view showing the main configuration of a crusher. FIG. 2 is a perspective view showing a part of the internal configuration of the crusher. FIG. 3 is a vertical cross-sectional view of the crushing roller unit shown in FIG. 2 . FIG. 3 is a side view of a main part of the crushing roller unit shown in FIG. 2 . 3 is a perspective view showing a main part of the crushing roller unit shown in FIG. 2 with the crushing roller removed. FIG. FIG. 4 is a partial enlarged view of a portion B of the crushing roller unit shown in FIG. 3 . 3 is a front view showing a main part of the crushing roller unit shown in FIG. 2 with the crushing roller removed. FIG. FIG. 3 is a top view of the crushing roller unit shown in FIG. 2 . FIG. 10 is a front view showing a crushing roller unit according to a second embodiment. FIG. 10 is a front view showing a crushing roller unit according to a third embodiment. FIG. 10 is a diagram showing a crushing roller unit according to a fourth embodiment. FIG. 10 is a diagram showing a crushing roller unit according to a fifth embodiment.

First Embodiment
A first embodiment of the present disclosure will be described below with reference to the drawings. Note that the embodiment described below is merely an example, and is not intended to exclude various modifications or applications of techniques not explicitly described in the following embodiment. The configurations of the following embodiment can be implemented in various modifications without departing from the spirit thereof, and can be selected or combined as needed.

The pulverizer (pulverizing device) 10 according to the present disclosure is used to pulverize raw materials into fine powder, and is typically a fine pulverizer (mill) that pulverizes carbon-containing solid fuels such as coal to produce finely pulverized fuel. The pulverizer can also be used to pulverize solid fuels such as biomass fuel and petroleum coke, ore, and other raw materials.

Note that in the following explanations, "up and down" refers to up and down in the vertical direction (the direction of gravity), and "left and right" refers to opposite directions in the horizontal direction relative to a certain subject.

[Configuration of the pulverizer]
The configuration of a pulverizer 10 according to this embodiment will be described with reference to FIG. 1. FIG. 1 is a vertical cross-sectional view showing the configuration of the main components of the pulverizer 10. As shown in FIG. 2, the pulverizer 10, also known as a vertical mill, includes a vertical, hollow cylindrical housing 11. An input pipe 14, through which raw material to be pulverized, e.g., solid fuel such as coal, is input, is disposed on a central axis C1 of a ceiling portion 11a of the housing 11. A pulverizer table 13, which pulverizes the raw material input from the input pipe 14, is disposed on a base 12 directly below the input pipe 14. The pulverizer table 13 is driven to rotate about a vertical axis along the central axis C1 by a drive unit (not shown).

A circular grinding surface 13a is formed on the vertical upper surface of the grinding table 13, concentric with the central axis C1. Vertically above the grinding surface 13a, multiple (e.g., two or three) grinding rollers 21 are arranged at equal intervals around the circumference, facing the grinding surface 13a. Each grinding roller 21 is rotatably supported at the tip of a journal shaft (rotation support shaft) 22, which is arranged so as to tilt vertically downward from the peripheral wall 11b of the housing 11 toward the central axis C1.

The journal shaft 22 is a shaft member supported by the journal head 23 and extending along the axis Y1. The crushing roller 21, journal shaft 22, and journal head 23 are included in the crushing roller unit 20. The crushing roller unit 20 is a device that crushes raw material supplied to the crushing table 13 from the feed pipe 14 between itself and the crushing table 13.

The journal head 23 is provided with pivot pins 24 that extend tangentially to the outer periphery of the grinding table 13 and protrude from the housing 11 on both sides (one tangential direction and the other). The grinding roller unit 20 is supported on the peripheral wall 11b via the pivot pins 24 so that it can swing toward and away from the grinding surface 13a.

As shown in Figure 1, the journal head 23 has a protrusion 23a that protrudes vertically downward, and a stopper 25 is attached to the peripheral wall 11b of the housing 11. The tip of the stopper 25 abuts against the protrusion 23a, restricting the approach of the crushing roller 21 to the crushing surface 13a. The stopper 25 is driven forward and backward by an actuator 25a, which adjusts the position of its tip and adjusts the closest position of the crushing roller 21 to the crushing surface 13a.

The crushing roller 21 also has a biasing device 26 that applies a load to crush the raw material. The biasing device 26 includes a hydraulic cylinder 26a fixed to the peripheral wall 11b and a plunger 26b that is driven axially by the hydraulic cylinder 26a. An arm portion 23b extends from the upper part of the journal head 23, and when the tip of the plunger 26b is pressed against the arm portion 23b, a downward load (toward the crushing surface 13a) is applied to the crushing roller 21 to crush the raw material on the crushing surface 13a.

An inlet port 15, located below the grinding table 13, is provided at the bottom of the housing 11 and through which carrier gas is fed. In this embodiment, air compressed by a blower (not shown) is fed into the housing 11 from this inlet port 15 as carrier gas, creating a high-pressure atmosphere inside the housing 11.

A rotary separator (classifying device) 17 is provided at the top of the housing 11, positioned around the outer periphery of the input tube 14, and classifies the pulverized raw material (hereinafter also referred to as powder or pulverized material) using a classifying blade 16. In addition, an outlet port 18 is provided in the ceiling portion 11a of the housing 11, through which the classified pulverized material is discharged outside the housing 11.

The raw material is crushed by the crushing roller 21 into pulverized material, and by driving a blower (not shown) connected to the inlet port 15, carrier gas is sent into the housing 11 from the inlet port 15. The upward swirling flow of carrier gas generated by the vanes 32a of the carrier gas outlet 32 (described below) causes the pulverized material to rise while drying.

The pulverized material that rises is separated by the rotary separator 17 into fine powder smaller than a specified particle size and coarse powder larger than a specified particle size. The fine powder passes through the rotary separator 17, rides on the flow of carrier gas, is discharged from the outlet port 18, and is transported from the pulverizer to another device (e.g., a boiler). The coarse powder either collides with the classification blade 16 of the rotary separator 17 and is repelled, or falls under its own weight while rising inside the housing 11, and is returned to the pulverizing table 13 for re-pulverization.

[Crushing roller unit and its peripheral configuration]
Next, the crushing roller unit 20 and its peripheral configuration will be described with reference to Figures 2 and 3. Figure 2 is a perspective view showing a part of the internal configuration of the crusher 10. Figure 3 is a vertical cross-sectional view of the crushing roller unit 20 shown in Figure 2.

As shown in Figures 2 and 3, an opening 11c is formed in the peripheral wall 11b of the housing 11. The journal head 23 is disposed in the opening 11c, and a swing shaft 24 protruding to the left and right is swingably supported on the peripheral wall 11b at the edge of the opening 11c. A cover 30 protruding radially from the peripheral wall 11b is attached to the opening 11c so as not to interfere with the journal head 23, separating the interior and exterior of the housing 11.

The crushing roller 21 is attached to a journal shaft 22 so as to be rotatable about axis Y1. The crushing roller 21 has a roller housing 21a with a shaft-shaped portion 21b and a roller body portion 21c that is fitted over the roller housing 21a and is detachable. The journal head 23 has a roller support portion 23c that supports the crushing roller 21. The protrusion portion 23a, arm portion 23b, and swing shaft 24 protrude downward, upward, left, and right from the roller support portion 23c and are supported by and in contact with a stopper 25, plunger 26b, and peripheral wall 11b, respectively.

The end (one end) of the journal shaft 22 facing the cover 30 is connected to the roller support portion 23c of the journal head 23. The roller housing 21a of the crushing roller 21 is rotatably attached to the end of the journal shaft 22 facing the central axis C1. The axis of the journal shaft 22 is inclined downward from the peripheral wall 11b of the housing 11 toward the central axis C1, with the inclination angle α being, for example, between 15 degrees and 40 degrees.

The carrier gas outlet 32 is located on the outer periphery of the grinding table 13 and is a device that blows carrier gas upward. The carrier gas is sent into the housing 11 by a blower (not shown) connected to the inlet port 15, and is blown upward from the carrier gas outlet 32, which is located between the outer periphery of the grinding table 13 and the peripheral wall 11b of the housing 11, as shown by arrow A1 in Figure 3.

Vane 32a is provided at the carrier gas outlet 32 on the outer periphery of the grinding table 13. The vane 32a applies a rotational force to the carrier gas blown vertically upward from the carrier gas outlet 32, forming a swirling upward flow that rotates spirally within the housing 11.

Directly above the carrier gas outlet 32 are the roller housing 21a of the grinding roller 21, the roller support portion 23c of the journal head 23, and the oscillating shaft 24. Therefore, the carrier gas blown from below toward the upward direction is blown onto the downward-facing surfaces of the roller housing 21a, roller support portion 23c, and oscillating shaft 24.

Inside the housing 11, the crushed material (powder) crushed by the crushing roller 21 on the crushing table 13 is blown up by the flow of this conveying gas, and some of it is blown onto the shaft portion 21b of the roller housing 21a, the roller support portion 23c, and the downward-facing surface of the oscillating shaft 24. When the powder collides with the downward-facing surfaces of these equipment parts, it causes wear and other damage to the collision points. For this reason, in the crushing roller unit 20, a roller journal protector 27 is attached to the roller journal portion 20J, which includes the roller support portion 23c of the journal head 23 and the shaft portion 21b of the crushing roller 21.

[Configuration of roller journal protector]
The roller journal protector 27 is a member that surrounds the lower portion of the journal shaft 22 at the position where the journal head 23 and the crushing roller 21 are adjacent to each other, and protects the crushing roller unit 20 from collision with powder carried by the carrier gas.

Figure 4 is a side view of the main parts of the crushing roller unit 20 shown in Figure 2. As shown in Figure 4, the roller journal protector 27 has an apron-shaped panel (mounting panel member) 27a and a shield (protective member) 27b. The apron-shaped panel 27a is detachably attached to the roller support portion 23c and protrusion portion 23a of the journal head 23.

The shield 27b is attached so that its base end 27bA is fixed to the apron-shaped panel 27a and surrounds the lower portion of the shaft-shaped portion 21b of the roller housing 21a. The apron-shaped panel 27a and shield 27b are made of steel (e.g., SS400, low-alloy steel, etc.).

The apron-shaped panel 27a is a flat plate that is attached to the roller support part 23c so that it extends around the roller support part 23c. The apron-shaped panel 27a not only attaches the shield 27b to the roller support part 23c, but also protects the roller support part 23c, the protrusion 23a, and the oscillating shaft 24 from collisions with the powder being transported.

Figure 5 is a perspective view showing the main parts of the crushing roller unit 20 with the crushing roller 21 shown in Figure 2 removed. As shown in Figure 5, the apron-shaped panel 27a is attached to the roller support portion 23c and is positioned in a plane perpendicular to the axis Y1 so as to extend over a substantially fixed distance from the outer periphery of the roller support portion 23c. The apron-shaped panel 27a is positioned so as to block part of the opening 11c in the peripheral wall 11b of the housing 11.

In areas of the surface of the apron-shaped panel 27a (the surface that receives the carrier gas from the carrier gas outlet 32) where powder collisions occur relatively frequently, ceramic tiles 27c made of hard ceramic, which have better wear resistance than the apron-shaped panel 27a, may be attached to reduce wear caused by powder collisions. Examples of hard ceramics include alumina, silica, zirconia, magnesia, silicon carbide, silicon nitride, etc., or mixtures of these. Alternatively, hardened ceramic plates may be used instead of ceramic tiles.

As shown in Figures 4 and 5, the shield 27b is formed in a semi-frustum shape so as to surround the semi-cylindrical region inside the peripheral wall 11b of the housing 11 at the vertically lower portion of the shaft portion 21b of the crushing roller 21. As shown in Figure 4, the shield 27b is formed in a semi-frustum shape (semi-polygonal truncated pyramid shape) with the other tip portion 27bB extending toward the roller main body 21c, surrounding the vertically lower portion of the shaft portion 21b. Powder is blown onto the vertically lower portion of the shaft portion 21b by the airflow of the carrier gas from the carrier gas outlet 32, but is protected by the shield 27b.

A ceramic tile (wear-resistant member) 27d made of a hard ceramic with better wear resistance than the shield 27b may be attached to the surface of the shield 27b (the surface that is hit by the carrier gas from the carrier gas outlet 32) to protect it from powder collisions. Examples of hard ceramics include alumina, silica, zirconia, magnesia, silicon carbide, silicon nitride, etc., or mixtures of these. Alternatively, a hardened plate may be used instead of the ceramic tile.

The shield 27b is shaped like a semi-frustum, and its diameter increases from the base end 27bA to the tip end 27bB in line with the outer periphery of the crushing roller 21, which increases in diameter from the shaft portion 21b to the roller body portion 21c. When the shield 27b is attached, the vertically lower region 27bC of the semi-frustum shape (here, the bottommost flat panel portion) is formed so that it slopes downward from the horizontal at an angle θ greater than or equal to the angle of repose of the powder from the base end 27bA to the tip end 27bB (toward the center of the housing 11).

Except for the lower region 27bC of the semi-frustum shape of the shield 27b, the entire surface is inclined downward from the horizontal from the base end 27bA to the tip end 27bB at an angle equal to or greater than that of the lower region 27bC. Therefore, the inner surface of the shield 27b (the upward-facing surface opposite the surface) is inclined at an angle equal to or greater than the angle of repose of the powder at every point.

The angle of repose of the powder is determined by the physical properties (powder characteristics) of the pulverized material and the surface condition of the shield 27b, so it is preferable to set the angle θ according to the type of raw material and the properties of the pulverized material (particle size distribution, etc.). It is even more preferable to set the angle θ to a value that is larger than the angle of repose of the powder and that covers the area that the powder hits as it is blown in the carrier gas airflow, while still allowing for some leeway within the placement space within the housing 11. For example, if the powder is pulverized coal, the angle θ should preferably be in the range of 40 degrees to 50 degrees.

[Configuration of the discharge section]
The crusher 10 of this embodiment has a discharge section 28 that discharges coarse particles LF (part of the crushed material obtained by crushing the raw material) that have entered the narrow space S1 formed between the shaft-shaped portion 21b of the crushing roller 21 and the shield 27b to the outside of the narrow space S1.

The roller journal protector 27 and discharge unit 28 constitute a discharge device that scrapes out coarse particles LF that have entered the narrow space S1 to the outside of the narrow space S1. The roller journal protector 27 and discharge unit 28 may be attached to the crushing roller unit 20 of the crusher 10, for example, during maintenance of a crusher 10 that does not have the roller journal protector 27 and discharge unit 28. The roller journal protector 27 and discharge unit 28 may also be attached to the crushing roller unit 20 when a new crusher 10 is manufactured.

Figure 6 is a partial enlarged view of portion B of the crushing roller unit 20 shown in Figure 3. As shown in Figure 6, a narrow space S1 is formed between the shaft portion 21b of the crushing roller 21 and the shield 27b. Below, the narrow space S1 communicates with the internal space S2 of the housing 11 via a gap CL formed at the position where the shaft portion 21b of the crushing roller 21 and the shield 27b are closest to each other.

As shown in Figure 6, if the diameter D1 of the coarse particles LF is larger than the distance L1 between the shaft portion 21b and the shield 27b in the gap CL, the coarse particles LF cannot pass through the gap CL and move into the internal space S2 of the housing 11. In this case, the coarse particles LF will accumulate in the narrow space S1. The discharge section 28 discharges the coarse particles LF that have accumulated in the narrow space S1 into the internal space S2 of the housing 11.

As shown in FIG. 6, the discharge portion 28 has an annular member 28a attached to the end surface 21bA of the shaft portion 21b of the crushing roller 21, facing the journal head 23. The annular member 28a is a plate-shaped member formed in an annular shape around the axis Y1, and is fixed to the shaft portion 21b, for example, with a fastening bolt (not shown). By detachably connecting the annular member 28a with the fastening bolt, the discharge portion 28 can be easily replaced if it becomes worn or damaged. Because the discharge portion 28 is fixed to the shaft portion 21b by the annular member 28a, it rotates about the axis Y1 as the crushing roller 21 rotates about the axis Y1.

Figure 7 is a front view showing the main parts of the crushing roller unit 20 with the crushing roller 21 shown in Figure 2 removed. Figure 8 is a top view of the crushing roller unit 20 shown in Figure 2. As shown in Figures 7 and 8, the discharge section 28 has a discharge member 28b, which is a plate-shaped member that extends parallel to the axis Y1 and extends in a radial direction perpendicular to the axis Y1.

The discharge member 28b is preferably manufactured from a wear-resistant material such as steel. It is also preferable to attach a replaceable protector (e.g., made of hard ceramic) to the surface of the discharge member 28b so that it can be replaced when it becomes worn.

As shown in Figure 7, it is preferable to provide multiple discharge members 28b. When multiple discharge members 28b are provided, they are arranged at intervals (e.g., regular intervals) along the rotation direction RD about the axis Y1. The discharge members 28b are joined to the surface of the annular member 28a facing the journal head 23. Therefore, each of the multiple discharge members 28b rotates about the axis Y1 as the crushing roller 21 rotates about the axis Y1.

As shown in FIG. 7, as the discharge member 28b rotates about the axis Y1, it comes into contact with the coarse particles LF that have accumulated in the narrow space S1, moving the coarse particles LF in the rotational direction RD along the inner surface of the shield 27b. When the discharge member 28b reaches a position where the shield 27b is not present, it discharges the coarse particles LF from the narrow space S1 into the internal space S2 of the housing 11.

In the above description, the discharge unit 28 is connected to the crushing roller 21 and receives rotational power from the crushing roller 21 to rotate about the axis Y1, but other configurations are also possible. For example, the discharge unit 28 may not be connected to the crushing roller 21, but may be connected to a rotation mechanism (not shown) driven by a power source such as an electric motor or air pressure.

In this case, the rotation mechanism rotates the discharge portion 28 about the axis Y1 independently of the crushing roller 21, discharging the coarse particles LF from the narrow space S1 into the internal space S2 of the housing 11. By rotating the discharge portion 28 about the axis Y1 independently of the crushing roller 21, even if, for example, the discharge member 28b becomes caught in coarse particles LF with an excessively large particle size and is unable to rotate, the rotation of the crushing roller 21 is minimally affected, allowing the crusher 10 to continue operating.

In the above description, the discharge member 28b of the discharge section 28 is joined to the annular member 28a, but other configurations are also possible. For example, the discharge section 28 may not include the annular member 28a, and the discharge member 28b may be joined directly to the end surface 21bA of the shaft portion 21b of the crushing roller 21 on the journal head 23 side by welding or the like.

In the above description, the discharge member 28b is joined to the surface of the annular member 28a facing the journal head 23, but other configurations are also possible. For example, it may be configured so that it is detachably attached to the annular member 28a. In this case, maintenance can be improved by individually replacing only the discharge member 28b that has become worn or damaged.

In the above description, the discharge section 28 has multiple discharge members 28b, but other configurations are also possible. For example, the discharge section 28 only needs to have at least one discharge member 28b.

In the above description, the discharge member 28b is formed in a plate shape, but other configurations are also possible. For example, it may be a rod-shaped member extending in a radial direction perpendicular to the axis Y1 or in a direction inclined from the radial direction. The cross section of the rod-shaped member may be circular, semicircular, round, C-shaped, polygonal, etc.

[Other configurations]
The crushing roller unit 20 of this embodiment has an intrusion prevention member 29 that prevents crushed material from entering the journal shaft 22 side of the narrow space S1 at the position where the journal head 23 and the crushing roller 21 are adjacent to each other. The intrusion prevention member 29 is a member that is L-shaped in cross section and is disposed at a position facing the discharge portion 28 in the axial direction along the axis Y1 and is fixed to the roller support portion 23c of the journal head 23. As shown in Figure 6, the intrusion prevention member 29, together with the shaft portion 21b of the crushing roller 21 and the shield 27b, forms the narrow space S1.

The operation and effects of the pulverizer of the present embodiment described above will now be described.
According to the crusher 10 of this embodiment, the carrier gas blown out from the carrier gas outlet 32 carries the crushed raw material (crushed material) upward inside the housing 11. The crushed material transported upward from the carrier gas outlet 32 toward the crushing roller 21 collides with the shield 27b, so that the crushing roller 21 is not worn down by collisions with the crushed material.

The shield 27b surrounds the lower portion of the journal shaft 22 where the journal head 23 and crushing roller 21 are adjacent, but the upper portion of the journal shaft 22 is open. As a result, some of the crushed material blown up falls onto the upper portion of the journal shaft 22 and enters the narrow space S1 formed between the crushing roller 21 and the shield 27b.

Powdered material with a particle size smaller than the gap CL formed between the crushing roller 21 and the shield 27b falls through the gap CL into the internal space S2 and does not accumulate on the inner surface of the shield 27b. On the other hand, powdered material with a particle size larger than the gap CL formed between the crushing roller 21 and the shield 27b does not fall through the gap CL into the internal space S2 and accumulates on the inner surface of the shield 27b.

In the crusher 10 of this embodiment, the discharge section 28 rotates about the axis Y1, causing crushed material that has entered and accumulated in the narrow space S1 formed between the crushing roller 21 and the shield 27b to be discharged to the outside of the narrow space S1. Therefore, even if crushed material with a particle size larger than the gap CL formed between the crushing roller 21 and the shield 27b enters the narrow space S1 formed between the crushing roller 21 and the shield 27b, it does not continue to accumulate in the narrow space S1. This prevents crushed material from accumulating in the narrow space S1 formed between the shield 27b and the crushing roller 21, which could cause wear on the inner surfaces of the crushing roller 21 and the shield 27b.

In the crusher 10 of this embodiment, the discharge member 28b of the discharge section 28, which is formed to extend in a radial direction perpendicular to the axis Y1, can be rotated around the axis Y1 to move the crushed material accumulated on the inner surface of the shield 27b along the inner surface of the shield 27b and discharge it outside the narrow space S1 formed between the shield 27b and the crushing roller 21.

In the crusher 10 of this embodiment, the discharge section 28 is attached to the crushing roller 21, so the power of the crushing roller 21 rotating about the axis Y1 can be used to rotate the discharge section 28 about the axis Y1.

Second Embodiment
Next, a crushing roller unit 20A according to a second embodiment of the present disclosure will be described with reference to Fig. 9. Fig. 9 is a front view showing the crushing roller unit 20A according to the second embodiment. Fig. 9 shows the state in which the crushing roller 21 has been removed. The crushing roller unit 20A according to this embodiment is similar to the crushing roller unit 20 according to the first embodiment, except for the points described below.

As shown in FIG. 9, the crushing roller unit 20A of this embodiment includes a discharge section 28 having a discharge member 28b. The discharge member 28b has a first member 28b1 arranged on the base end side (the side closest to the axis Y1) in the radial direction perpendicular to the axis Y1, and a second member 28b2 arranged on the tip side (the side away from the axis Y1) in the radial direction. The second member 28b2 is attached to the first member 28b1.

The first member 28b1 is made of, for example, steel and has enough rigidity to prevent elastic deformation even when it comes into contact with the coarse particles LF. On the other hand, as shown in Figure 9, the second member 28b2 rotates around the axis Y1 while in contact with the shield 27b and elastically deformed. It is preferable to use a wire brush, for example, a bundle of metallic wire members, as the second member 28b2.

As shown in Figure 9, when the shield 27b is formed in a polygonal shape around the axis Y1 to cover the underside of the journal shaft 22, the distance from the axis Y1 to the shield 27b is not constant. The shortest point in the distance from the axis Y1 to the shield 27b is R1, and the longest point is R2. By providing an elastically deformable second member 28b2 at the tip end of the discharge member 28b, the second member 28b2 can be reliably brought into contact with the inner surface of the shield 27b, even if the distance from the axis Y1 to the shield 27b varies depending on the rotational position. This ensures that the coarse particles LF can be reliably discharged from the narrow space S1 to the internal space S2 of the housing 11.

In this embodiment, it is desirable to make the opening width W2 between the end of the shield 27b downstream in the rotation direction RD and the intrusion prevention member 29 narrower than the opening width W1 between the end of the shield 27b upstream in the rotation direction RD and the intrusion prevention member 29. The position at which opening width W1 is achieved is the position at which the discharge portion 28 discharges coarse particles LF.

On the other hand, the position where the opening width W2 is set is a position where the discharge section 28 does not discharge coarse particles LF. By narrowing the opening width W2 at the position where coarse particles LF are not discharged, it is possible to prevent coarse particles LF from entering the narrow space S1. Furthermore, by narrowing the opening width W2 at the position where coarse particles LF are not discharged, it is possible to promote the discharge of coarse particles LF from the narrow space S1.

In the crusher 10 of this embodiment, the second member 28b2 rotates around the axis Y1 while in contact with the shield 27b and elastically deformed. Therefore, even if the shield 27b has a polygonal shape whose distance from the axis Y1 changes at each position around the axis Y1, the second member 28b2 rotates while maintaining contact with the shield 27b, and crushed material accumulated on the inner surface of the shield 27b can be reliably discharged outside the narrow space S1 formed between the shield 27b and the crushing roller 21.

Third Embodiment
Next, a crushing roller unit 20B according to a third embodiment will be described with reference to Fig. 10. Fig. 10 is a front view of the crushing roller unit 20B according to the third embodiment. Fig. 10 shows the crushing roller unit 20B with the crushing roller 21 removed. The crushing roller unit 20B according to this embodiment is similar to the crushing roller unit 20 according to the first embodiment, except for the points described below.

As shown in FIG. 10, the crushing roller unit 20B of this embodiment includes a discharge section 28 having a discharge member 28b. The discharge member 28b includes a plate-shaped base end member 28b3 located on the base end side (the side closest to the axis Y1) in the radial direction perpendicular to the axis Y1, and a plate-shaped guide member 28b4 located on the tip end side (the side away from the axis Y1) in the radial direction. The guide member 28b4 is longer than the base end member 28b3 and is attached to the base end member 28b3.

As shown in Figure 10, the discharge section 28 has a recess 28b5 for accommodating coarse particles LF at the position where the base-end member 28b3 and the guide member 28b4 are butt-joined. The recess 28b5 accommodates coarse particles LF that have entered the narrow space S1 and discharges them to the outside of the narrow space S1.

As shown in Figure 10, the discharge section 28 of this embodiment rotates with coarse particles LF contained in the recess 28b5 within a range of approximately 180 degrees from the bottom of the narrow space S1. When the discharge section 28 rotates more than 180 degrees from the bottom of the narrow space S1, the coarse particles LF shown by the dotted line fall from the recess 28b5. The coarse particles LF that fall from the recess 28b5 are guided by the guide member 28b4 of the discharge member 28b, which is arranged downstream in the rotation direction RD, to prevent them from entering the narrow space S1.

In this way, the guide members 28b4 are arranged at multiple locations at intervals in the rotation direction RD and guide the coarse particles LF discharged from the recesses 28b5 of other discharge sections 28 adjacent to them on the upstream side in the rotation direction RD so that they do not enter the narrow space S1.

In the crusher 10 of this embodiment, by rotating the discharge section 28, which contains coarse particles LF in the recess 28b5, the coarse particles LF that accumulate on the shield 27b can be reliably discharged outside the narrow space S1 formed between the shield 27b and the crushing roller 21.

In the crusher 10 of this embodiment, the coarse particles LF discharged from the recess 28b5 of another adjacent discharge section 28 on the upstream side in the rotation direction RD are guided by the plate-shaped guide member 28b4 to prevent the coarse particles LF discharged from the recess 28b5 from entering the narrow space S1. This reliably prevents the coarse particles LF discharged from the narrow space S1 between the shield 27b and the crushing roller 21 from re-entering the narrow space S1.

Fourth Embodiment
Next, a crushing roller unit 20C according to a fourth embodiment will be described with reference to Fig. 11. Fig. 11 is a diagram showing the crushing roller unit 20C according to the fourth embodiment. The crushing roller unit 20C according to this embodiment is the same as the crushing roller unit 20 according to the first embodiment, except for the points described below.

As shown in FIG. 11, the crushing roller unit 20C of this embodiment includes a discharge section 28 having a discharge member 28b. The crushing roller unit 20C also includes a fixed member 29a that is fixed to the journal head 23 via an intrusion prevention member 29. The fixed member 29a is positioned opposite the tip of the discharge section 28 in the axial direction along the axis Y1.

The fixed member 29a has multiple protrusions 29b that are spaced apart in the rotational direction RD and protrude from the journal head 23 toward the discharge portion 28. The protrusions 29b are bonded to the fixed member 29a. Because the fixed member 29a is fixed to the journal head 23, the protrusions 29b do not rotate even when the discharge portion 28 rotates in the rotational direction RD. Therefore, when the coarse particles LF moving in the rotational direction RD by the discharge member 28b collide with the protrusions 29b, the coarse particles LF are sandwiched between the discharge member 28b and the protrusions 29b and pulverized.

In the crusher of this embodiment, the coarse particles LF move along the inner surface of the shield 27b due to the discharge part 28 rotating about the axis Y1, and are crushed by coming into contact with the protrusions 29b. If the particle size of the crushed coarse particles LF is smaller than the gap CL formed between the crushing roller 21 and the shield 27b, the crushed coarse particles LF are discharged through the gap CL to the outside of the narrow space S1 (the internal space S2 of the housing 11).

In the crusher of this embodiment, it is desirable to provide a load reduction mechanism (not shown) on at least one of the discharge portion 28 and the fixed member 29a that can move in the rotation direction RD when a load of a predetermined value or greater is applied in the rotation direction RD. This prevents damage to the discharge portion 28 or the fixed member 29a caused by a load exceeding the predetermined value being applied when coarse particles LF become caught between the discharge portion 28 and the fixed member 29a.

Fifth Embodiment
Next, a crushing roller unit 20D according to a fifth embodiment will be described with reference to Fig. 12. Fig. 12 is a diagram showing the crushing roller unit 20D according to the fifth embodiment. The crushing roller unit 20D according to this embodiment is the same as the crushing roller unit 20 according to the first embodiment, except for the points described below.

As shown in FIG. 12 , the discharge section 28 of this embodiment has a plate-shaped discharge member 28b extending in an inclined direction from the axis Y1. The tip end of the discharge member 28b is located upstream in the rotational direction RD relative to the base end joined to the annular member 28a. By inclining the extension direction of the discharge member 28b toward the upstream side of the rotational direction RD relative to the axis Y1, the coarse particles LF can be moved from the crushing roller 21 side toward the journal head 23 side. As shown in FIG. 12 , the coarse particles LF move from the position indicated by the dotted line toward the position indicated by the solid line, from the crushing roller 21 side toward the journal head 23 side. This prevents the crushing roller 21 from coming into contact with the coarse particles LF and wearing them down. Furthermore, the coarse particles LF can be pressed against the journal head 23 to promote crushing of the coarse particles LF.

The discharge device described in each of the above-described embodiments can be understood, for example, as follows:

The discharge device attached to the crushing device (10) according to one aspect of the present disclosure is attached to the crushing device (10) that crushes raw materials, and the crushing device includes a crushing table (13), a crushing roller unit (300) that crushes the raw materials supplied to the crushing table from a supply unit between the crushing table and the crushing table, and an outlet (32) that is provided on the outer periphery of the crushing table and blows out a conveying gas upward, and the crushing roller unit includes a journal head (23) attached to the housing (11) and a roller support (24) that is supported by the journal head and The device has a journal shaft (22) extending along an axis (Y1) and a crushing roller (21) attached to the journal shaft so as to be rotatable about the axis. It also includes a protective member (27b) that surrounds the lower portion of the journal shaft at a position where the journal head and the crushing roller are adjacent and protects the crushing roller unit from crushed material produced by crushing the raw material transported by the carrier gas, and a discharge section (28) that rotates about the axis and discharges crushed material that has entered the space formed between the crushing roller and the protective member to the outside of the space.

In the discharge device according to one aspect of the present disclosure, the carrier gas blown out from the outlet transports the pulverized material inside the housing upward. The pulverized material transported upward from the outlet toward the crushing roller collides with the protective member, preventing the crushing roller from being worn down by collisions with the pulverized material.

The protective member surrounds the lower portion of the journal shaft where the journal head and crushing roller are adjacent, but the upper portion of the journal shaft is open. As a result, crushed material blown up into the upper portion of the journal shaft falls and enters the space formed between the crushing roller and the protective member. Crushed material with a particle size smaller than the gap formed between the crushing roller and the protective member falls downward through the gap and does not accumulate on the inner surface of the protective member. On the other hand, crushed material with a particle size larger than the gap formed between the crushing roller and the protective member does not fall downward through the gap and accumulates on the inner surface of the protective member.

In a discharge device according to one aspect of the present disclosure, the discharge section rotates about its axis, causing crushed material that has entered and accumulated in the space formed between the crushing roller and the protective member to be discharged to the outside of the space. Therefore, even if crushed material with a particle size larger than the gap formed between the crushing roller and the protective member enters the space formed between the crushing roller and the protective member, it does not continue to accumulate in the space. This prevents crushed material from accumulating in the space formed between the protective member and the crushing roller, which can cause wear on the inner surfaces of the crushing roller and the protective member.

In the discharge device according to the aspect of the present disclosure, the discharge portion may be configured to extend in a radial direction perpendicular to the axis.
With the discharge device of this configuration, by rotating the discharge section, which is formed to extend in a radial direction perpendicular to the axis, around the axis, the crushed material accumulated on the inner surface of the protective member can be moved along the inner surface of the protective member and discharged outside the space formed between the protective member and the crushing roller.

In one aspect of the discharge device of the present disclosure, the discharge section may have a first member (28b1) arranged on the base end side in the radial direction, and a second member (28b2) arranged on the tip end side in the radial direction and attached to the first member, and the second member may be configured to rotate around the axis while in contact with the protective member and elastically deformed.

With this discharge device, the second member rotates around the axis while in contact with the protective member and elastically deformed. Therefore, even if the protective member has a polygonal shape whose distance from the axis changes at each position around the axis, the second member rotates while maintaining contact with the protective member, and crushed material that accumulates on the inner surface of the protective member can be reliably discharged outside the space formed between the protective member and the crushing roller.

In the discharge device according to the aspect of the present disclosure, the discharge portion may be a plate-shaped member extending parallel to the axis.
With this discharge device, the discharge section, which is a plate-shaped member extending parallel to the axis, can be rotated around the axis to move the crushed material along the inner surface of the protective member and discharge it outside the space formed between the protective member and the crushing roller.

In the discharge device configured as described above, the crushing roller unit may have a fixed member (29a) that is positioned opposite the tip of the discharge section in the axial direction along the axis and is fixed to the journal head, and the fixed member may have a plurality of protrusions (29b) that are spaced apart in the rotational direction of the discharge section and protrude from the journal head toward the discharge section.

In this discharge device, the fixed member fixed to the journal head has multiple protrusions spaced apart in the rotational direction. Therefore, the pulverized material, which moves along the inner surface of the protective member as the discharge member rotates around its axis, comes into contact with the protrusions and is pulverized. If the particle size of the pulverized material is smaller than the gap formed between the crushing roller and the protective member, the pulverized material passes through the gap and is discharged to the outside of the space.

In the discharge device of the above aspect, at least one of the discharge portion and the fixed member may have a load reduction mechanism that is movable in the rotation direction when a load equal to or greater than a predetermined value is applied in the rotation direction.
According to the discharge device of this embodiment, at least one of the discharge portion and the fixed member has a load reduction mechanism, so that when the crushed material gets caught between the discharge portion and the fixed member, a load exceeding a predetermined value is applied, which prevents damage to the discharge portion or the fixed member.

In the discharge device according to the aspect of the present disclosure, the discharge portion may be a plate-shaped member extending in a direction inclined from the axis.
With this discharge device, the discharge section, which is a plate-shaped member extending in an inclined direction from the axis, can be rotated around the axis to move the crushed material along the inner surface of the protective member and discharge it outside the space formed between the protective member and the crushing roller.

Furthermore, for example, by tilting the roller toward the upstream side of the axis in the direction of rotation, the crushed material can be moved from the crushing roller side to the journal head side. This prevents the crushing roller from coming into contact with the crushed material and wearing down. It also presses the crushed material against the journal head, facilitating the crushing of the material.

In the discharge device according to one aspect of the present disclosure, the discharge section may be configured to have a recess (28b5) that accommodates the pulverized material that has entered the space.
With this discharge device, by rotating the discharge section which contains the crushed material in the recess, the crushed material accumulated on the protective member can be reliably discharged outside the space formed between the protective member and the crushing roller.

In a discharge device of this configuration, the discharge sections may be arranged at multiple locations spaced apart in the rotational direction and may have a plate-shaped guide member (28b4) that guides the pulverized material discharged from the recess of another discharge section adjacent to the discharge section upstream in the rotational direction so that it does not enter the space.

With this discharge device, crushed material discharged from the recess of another discharge section adjacent to the upstream side in the rotation direction is guided by a plate-shaped guide member to prevent the crushed material discharged from the recess from entering the space. This ensures that crushed material discharged from the space between the protective member and the crushing roller is prevented from re-entering the space.

In the discharge device according to the aspect of the present disclosure, the discharge portion may be a rod-shaped member having a circular or polygonal cross section.
With the discharge device of this configuration, a discharge section with a relatively simple configuration using a rod-shaped member with a circular or polygonal cross section can be used to enter the space formed between the crushing roller and the protective member and discharge accumulated crushed material to the outside.

In the discharge device according to one aspect of the present disclosure, the discharge section may be attached to the crushing roller and rotate together with the crushing roller about the axis.
According to the discharge device of this configuration, the discharge portion is attached to the crushing roller, so that the power of the crushing roller rotating about its axis can be used to rotate the discharge portion about its axis.

In the discharge device according to the aspect of the present disclosure, the protective member may have a wear-resistant member attached to a surface facing the space.
According to the discharge device of this configuration, a wear-resistant member is attached to the space-side surface of the protective member, thereby preventing the protective member from being damaged by contact with crushed material that accumulates on the inner surface of the protective member.

A crushing device according to one aspect of the present disclosure includes any one of the discharge devices described above, a crushing table, a crushing roller unit that crushes the raw material supplied to the crushing table from a raw material supply unit between the crushing table and the table, and an outlet provided on the outer periphery of the crushing table and that blows conveying gas upward. The crushing roller unit has a journal head attached to a housing, a journal shaft supported by the journal head and extending along an axis, and a crushing roller attached to the journal shaft so as to be rotatable about the axis.

The crushing device according to one aspect of the present disclosure can prevent crushed material from accumulating in the space formed between the crushing roller and the protective member that protects the crushing roller unit from crushed material transported by the carrier gas, thereby preventing wear on the inner surfaces of the crushing roller and the protective member.

The operating method of the grinding device described in each of the above-described embodiments can be understood, for example, as follows.

A method of operating a crushing device according to one aspect of the present disclosure is a method of operating a crushing device that crushes raw materials, the method comprising: a crushing table; a crushing roller unit (300) that crushes the raw materials supplied to the crushing table from a raw material supply unit between the crushing table and the crushing roller unit; and an outlet provided on the outer periphery of the crushing table and that blows a conveying gas upward; the crushing roller unit having a journal head attached to a housing; a journal shaft supported by the journal head and extending along an axis; a crushing roller attached to the journal shaft so as to be rotatable about the axis; and a protective member that surrounds a lower portion of the journal shaft at a position adjacent to the journal head and the crushing roller and protects the crushing roller unit from crushed material produced by crushing the raw materials transported by the conveying gas; and a discharge step of rotating a discharge unit about the axis to discharge crushed material that has entered a space formed between the crushing roller and the protective member to the outside of the space.

In a method for operating a crushing device according to one aspect of the present disclosure, the carrier gas blown out from the outlet transports crushed material inside the housing upward. The crushed material transported upward from the outlet toward the crushing roller collides with the protective member, preventing the crushing roller from being worn down by collisions with the crushed material.

The protective member surrounds the lower portion of the journal shaft where the journal head and crushing roller are adjacent, but the upper portion of the journal shaft is open. As a result, crushed material blown up into the upper portion of the journal shaft falls and enters the space formed between the crushing roller and the protective member. Crushed material with a particle size smaller than the gap formed between the crushing roller and the protective member falls downward through the gap and does not accumulate on the inner surface of the protective member. On the other hand, crushed material with a particle size larger than the gap formed between the crushing roller and the protective member does not fall downward through the gap and accumulates on the inner surface of the protective member.

In a method for operating a crushing device according to one aspect of the present disclosure, the discharge section is rotated about its axis during the discharge process, thereby discharging crushed material that has entered and accumulated in the space formed between the crushing roller and the protective member to the outside of the space. Therefore, even if crushed material with a particle size larger than the gap formed between the crushing roller and the protective member enters the space formed between the crushing roller and the protective member, it does not continue to accumulate in the space. This prevents crushed material from accumulating in the space formed between the protective member and the crushing roller, which can cause wear on the inner surfaces of the crushing roller and the protective member.

10. Crusher (crushing device)
11 Housing 13 Crushing table 20, 20A, 20B, 20C, 20D Crushing roller unit 20J Roller journal portion 21 Crushing roller 21a Roller housing 21b Shaft-shaped portion 21c Roller body portion 22 Journal shaft 23 Journal head 23a Projection portion 27 Roller journal protector 27a Apron-shaped panel 27b Shield (protective member)
28 Discharge portion 28a Annular member 28b Discharge member 28b1 First member 28b2 Second member 28b3 Base end side member 28b4 Guide member 28b5 Recess 29 Intrusion prevention member 29a Fixing member 29b Projection 32 Carrier gas outlet 32a Vane C1 Central axis CL Gap LF Coarse grain RD Rotation direction S1 Narrow space S2 Internal space Y1 Axis

Claims (14)

A discharge device attached to a crushing device that crushes raw materials,
The grinding device is
A grinding table;
a crushing roller unit that crushes the raw material supplied from the raw material supply unit to the crushing table between the raw material supply unit and the crushing table;
an outlet provided on the outer periphery of the rotary table for blowing out a carrier gas upward;
The crushing roller unit includes:
a journal head attached to the housing;
a journal shaft supported by the journal head and extending along an axis;
a crushing roller attached to the journal shaft so as to be rotatable about the axis;
a protective member that surrounds a lower portion of the journal shaft at a position where the journal head and the crushing roller are adjacent to each other and protects the crushing roller unit from crushed material obtained by crushing the raw material and transported by the carrier gas;
a discharge section that rotates about the axis and discharges the crushed material that has entered the space formed between the crushing roller and the protective member to the outside of the space. The discharge device described in claim 1, wherein the discharge portion is formed to extend radially perpendicular to the axis. the discharge portion has a first member arranged on a base end side in the radial direction, and a second member arranged on a tip end side in the radial direction and attached to the first member,
The discharge device according to claim 2 , wherein the second member rotates about the axis in a state of being in contact with the protection member and being elastically deformed. The discharge device described in claim 2, wherein the discharge portion is a plate-shaped member extending parallel to the axis. a fixing member disposed at a position opposite to a tip of the discharge portion in an axial direction along the axis and fixed to the journal head;
The ejection device according to claim 4 , wherein the fixing member has a plurality of protrusions that are spaced apart in the rotational direction of the ejection portion and that protrude from the journal head toward the ejection portion. The ejection device described in claim 5, wherein at least one of the ejection section and the fixed member has a load reduction mechanism that is movable in the rotational direction when a load equal to or greater than a predetermined value is applied in the rotational direction. The discharge device described in claim 2, wherein the discharge portion is a plate-shaped member extending in an inclined direction from the axis. The discharge device according to claim 1, wherein the discharge section has a recess that accommodates the pulverized material that has entered the space. The discharge device described in claim 8, wherein the discharge sections are arranged at multiple locations spaced apart in the rotational direction and have plate-shaped guide members that guide the pulverized material discharged from the recesses of adjacent discharge sections upstream in the rotational direction so that it does not enter the space. The discharge device described in claim 2, wherein the discharge portion is a rod-shaped member having a circular or polygonal cross section. The discharge device described in any one of claims 1 to 10, wherein the discharge unit is attached to the crushing roller and rotates around the axis together with the crushing roller. The discharge device described in any one of claims 1 to 11, wherein the protective member has a wear-resistant member attached to the surface facing the space. An ejection device according to any one of claims 1 to 12;
A grinding table;
a crushing roller unit that crushes the raw material supplied from the raw material supply unit to the crushing table between the raw material supply unit and the crushing table;
an outlet provided on the outer periphery of the rotary table for blowing out a carrier gas upward;
The crushing roller unit includes:
a journal head attached to the housing;
a journal shaft supported by the journal head and extending along an axis;
a crushing roller attached to the journal shaft so as to be rotatable about the axis. A method for operating a grinding device for grinding a raw material, comprising:
The grinding device is
A grinding table;
a crushing roller unit that crushes the raw material supplied from the raw material supply unit to the crushing table between the raw material supply unit and the crushing table;
an outlet provided on the outer periphery of the rotary table for blowing out a carrier gas upward;
The crushing roller unit includes:
a journal head attached to the housing;
a journal shaft supported by the journal head and extending along an axis;
a crushing roller attached to the journal shaft so as to be rotatable about the axis;
a protective member surrounding a lower portion of the journal shaft at a position where the journal head and the crushing roller are adjacent to each other to protect the crushing roller unit from crushed material obtained by crushing the raw material transported by the carrier gas,
A method for operating a crushing device, comprising a discharge step of rotating a discharge section about an axis to discharge crushed material that has entered a space formed between the crushing roller and the protective member to the outside of the space.