crusher

Abstract

This crusher 100 comprises: a rotating table; an air chamber 17 defined below the table; an air intake duct 15 which has an outlet 15a in a side wall 17a of the air chamber 17, the outlet 15a being separated from a floor surface 17b of the air chamber 17; a scraper 22 which is disposed along the floor surface 17b and rotates around the rotation axis of the table, and which extends radially outward with respect to the rotation axis; and a top plate 25 which is connected to an advancing side in the rotation direction with respect to a radial outside end section of the scraper 22 and is disposed so as to face the floor surface 17b, the top plate 25 being disposed at a height equal to or lower than that of a lower end 15b of the outlet 15a.

Description

[Technical Field]

[0001] This application claims the benefit of priority from Japanese Patent Application No. 2023-002553, filed on January 11, 2023, the contents of which are incorporated herein by reference. [Background technology]

[0002] A crusher is configured to crush material on a rotating table using a table and roller tires that rotate on the table. Most of the crushed material is carried to the top of the crusher by air blown upward from an air chamber below the table. However, some of the material falls into the air chamber. For this reason, crushers may be equipped with a scraper to remove foreign matter from the air chamber.

[0003] For example, Patent Document 1 discloses a vertical mill equipped with a scraper for removing foreign matter from an air tunnel below a grinding table. The scraper rotates integrally with the grinding table. An air intake duct is provided on the side wall of the air tunnel. With this configuration, foreign matter is pushed radially outward by centrifugal force from the scraper. Therefore, the foreign matter pushed out by the scraper can accumulate at the outlet of the air intake duct, which can be a problem. Therefore, the scraper in Patent Document 1 includes a hook portion bent in the rotational direction at its radially outer end. With this configuration, foreign matter is blocked by the hook portion at the radially outer end. Therefore, accumulation of foreign matter at the outlet of the air intake duct is prevented. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 62-45351 Summary of the Invention [Problem to be solved by the invention]

[0005] As mentioned above, in pulverizers, accumulation of foreign matter at the outlet of the air intake duct can be a problem.

[0006] An object of the present disclosure is to provide a pulverizer that can suppress the accumulation of foreign matter at the outlet of the air supply duct. [Means for solving the problem]

[0007] In order to solve the above problems, a crusher according to one embodiment of the present disclosure comprises a rotating table, an air chamber defined below the table, an air intake duct having an outlet on a side wall of the air chamber, the outlet being spaced apart from the floor of the air chamber, a scraper arranged along the floor and rotating around the rotation axis of the table, the scraper extending radially outward relative to the rotation axis, and a top plate connected to the radially outer end of the scraper on the forward side in the rotation direction and arranged to face the floor, the top plate being arranged at a height below the lower end of the outlet.

[0008] The crusher may include a side plate connected to the radially outer end of the scraper on the forward direction side in the rotational direction and facing the side wall.

[0009] The top plate may be positioned at a height higher than the upper edge of the scraper, and the grinder may include a connecting plate connecting the top plate to the upper edge of the scraper.

[0010] The crusher may be provided with a Russell plate that is arranged at a distance from the scraper on the forward side of the rotation direction and rotates integrally with the scraper, and the Russell plate may be arranged at an angle to the scraper in a plan view, and the distance from the radially outer end of the scraper to the radially outer end of the Russell plate may be greater than the distance from the radially outer end of the scraper to the forward end of the top plate.

[0011] A crusher according to another aspect of the present disclosure includes a rotating table, an air chamber defined below the table, a scraper arranged along the floor of the air chamber and rotating around the center of rotation of the table, the scraper extending radially outward from the center of rotation, a side plate connected to the radially outer end of the scraper on the forward side in the direction of rotation and facing the side wall of the air chamber, and a top plate connected to the radially outer end of the scraper on the forward side in the direction of rotation and positioned so as to face the floor of the air chamber. [Effects of the Invention]

[0012] According to the present disclosure, in a pulverizer, accumulation of foreign matter at the outlet of the air supply duct can be suppressed. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a schematic cross-sectional side view showing a crusher according to an embodiment. [Figure 2] FIG. 2 is a schematic perspective view showing a scraper unit according to the embodiment. [Figure 3] FIG. 3 is a schematic side view showing the scraper unit according to the embodiment. [Figure 4] FIG. 4 is a schematic plan view showing the scraper unit according to the embodiment. [Figure 5] FIG. 5 is a schematic front view showing the scraper unit according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Specific dimensions, materials, numerical values, etc. shown in the embodiments are merely examples for ease of understanding and do not limit the present disclosure unless otherwise specified. In this specification and drawings, elements having substantially the same functions and configurations are designated by the same reference numerals to avoid redundant explanation, and elements not directly related to the present disclosure are not shown.

[0015] FIG. 1 is a schematic side cross-sectional view showing a pulverizer 100 according to an embodiment. For example, the pulverizer 100 pulverizes coal into pulverized coal. In other embodiments, the pulverizer 100 may pulverize other materials, such as biomass. For example, the pulverizer 100 includes a casing 1, a table 2, and a plurality of roller tire assemblies 50. Note that only one roller tire assembly 50 is shown in FIG. 1. The pulverizer 100 may further include other components.

[0016] For example, casing 1 has a generally cylindrical shape and is disposed so that its central axis extends in the vertical direction. A cylindrical chute 11 is provided in the center of the upper part of casing 1. Chute 11 is disposed so that its central axis extends in the vertical direction. A cylindrical outlet portion 16 is provided on the side of chute 11. Also, inside casing 1, reject chute 12 and rotary classifier 13 are provided around chute 11. Reject chute 12 has, for example, a truncated cone shape and is disposed coaxially with chute 11. Reject chute 12 is provided with a slit 12a.

[0017] The table 2 is provided below the chute 11 inside the casing 1. The table 2 has a roughly disk-shaped portion. For example, the table 2 is rotated around a vertical axis by a motor 3 via a reducer 4. An annular groove 2a is formed on the top surface of the table 2.

[0018] In this disclosure, the "axial direction," "radial direction," "circumferential direction," and "rotational direction" relative to the rotation axis of table 2 may be simply referred to as the "axial direction," "radial direction," "circumferential direction," and "rotational direction," respectively.

[0019] A plurality of airport ports 14 are provided around the periphery of the table 2. Note that only one airport port 14 is shown in FIG.

[0020] A primary air chamber 17 is defined below the table 2. For example, the primary air chamber 17 has a generally annular shape. The primary air chamber 17 is in fluid communication with the air port 14. An air supply duct 15 is provided in the primary air chamber 17. The air supply duct 15 has an outlet 15a in a side wall 17a of the primary air chamber 17. Air is supplied to the primary air chamber 17 from the air supply duct 15. The air is blown up into the space above the table 2 via the air port 14.

[0021] The roller tire assembly 50 is provided inside the casing 1 on the side wall of the casing 1. A plurality of roller tire assemblies 50 are arranged around the table 2, spaced apart from one another along the circumferential direction of the table 2. The roller tires 51 of the roller tire assemblies 50 have a profile that engages with the grooves 2a of the table 2. The roller tires 51 are driven by the rotation of the table 2 due to friction between the roller tires 51 and the grooves 2a.

[0022] The roller tire assembly 50 is swingable about a horizontal pivot shaft 58, and is pushed in the swinging direction by a cylinder 5, such as a hydraulic cylinder, via a plunger 6. With this configuration, the roller tire 51 is pressed against the groove 2a of the table 2.

[0023] In the above-described pulverizer 100, coal is fed into the casing 1 through the chute 11. The coal falls onto the upper surface of the table 2. The coal on the table 2 is pulverized into pulverized coal by the roller tires 51 and the grooves 2a of the table 2. Most of the pulverized coal is blown upward by air from the air port 14. The pulverized coal passes through the slits 12a of the reject chute 12, and coarse particles are removed by the classifier 13. The pulverized coal that has passed through the classifier 13 is sent from the outlet 16 to a subsequent process (for example, a boiler burner).

[0024] A portion of the pulverized coal falls from the air port 14 into the primary air chamber 17. For this reason, the pulverizer 100 is provided with one or more scraper units 20 for removing foreign matter from the primary air chamber 17. For example, the scraper unit 20 is attached to the table 2 and configured to rotate integrally with the table 2. The scraper unit 20 scrapes up the foreign matter accumulated in the primary air chamber 17 and discharges the scraped up foreign matter from an outlet provided on the floor surface 17b of the primary air chamber 17 into a pyrite box (not shown). For example, the pulverizer 100 is provided with multiple scraper units 20 arranged at equal intervals along the circumferential direction. Note that only one scraper unit 20 is shown in FIG. 1.

[0025] FIG. 2 is a schematic perspective view showing the scraper unit 20 according to the embodiment. In FIG. 2, the rotation direction of the table 2 is indicated by an arrow R. For example, the scraper unit 20 includes a base 21, a scraper 22, and a Russell plate 23. In the present disclosure, the scraper 22 may also be referred to as an "outer scraper." The scraper unit 20 may also include an inner scraper (not shown) that is arranged radially inward of the scraper 22.

[0026] The base 21 supports the scraper 22 and the Russell plate 23. For example, the base 21 may be fixed to the shaft or the underside of the table 2 by a fixing part such as a bracket or a pole (not shown). Therefore, the base 21 rotates integrally with the table 2.

[0027] Fig. 3 is a schematic side view showing the scraper unit 20 according to the embodiment, as viewed from the circumferential direction of the scraper unit 20. Fig. 3 shows a cross-sectional view as viewed from the opposite side to Fig. 1, and in Fig. 3, the air supply duct 15 is shown on the opposite side (left side) to Fig. 1.

[0028] The scraper 22 is disposed along the floor surface 17b of the primary air chamber 17. Specifically, the scraper 22 is supported by the base 21 so that a small gap is formed between the lower edge of the scraper 22 and the floor surface 17b. For example, the scraper 22 is fixed to a support plate 21a provided on the base 21. Since the scraper 22 is supported by the base 21, which rotates integrally with the table 2, the scraper 22 also rotates integrally with the table 2.

[0029] 2, the scraper 22 extends radially outward relative to the rotation axis of the table 2. For example, the scraper 22 is inclined relative to the vertical direction so that the upper edge of the scraper 22 is located on the forward direction side of the rotation direction R relative to the lower edge.

[0030] Referring to FIG. 3, in this embodiment, the lower end 15b of the outlet 15a of the air supply duct 15 is spaced from the floor surface 17b of the primary air chamber 17. Furthermore, in this embodiment, a slope 17c is provided between the side wall 17a and the floor surface 17b of the primary air chamber 17. In this embodiment, the upper edge of the scraper 22 is disposed at a height lower than the lower end 15b of the outlet 15a and higher than the slope 17c. That is, the upper edge of the scraper 22 is disposed at a height between the floor surface 17b and the lower end 15b of the outlet 15a. Furthermore, the scraper 22 is disposed so that a small gap is formed between the radially outer end face of the scraper 22 and the slope 17c.

[0031] 2, a side plate 24, a top plate 25, and a connecting plate 26 are provided at the radially outer end of the scraper 22. The side plate 24, the top plate 25, and the connecting plate 26 are connected to the scraper 22 on the forward side in the rotational direction R.

[0032] For example, the side plate 24 is connected to the upper edge of the scraper 22 via a connecting plate 26. The side plate 24 is disposed at a higher position than the scraper 22. The side plate 24 is spaced apart from the floor surface 17b of the primary air chamber 17.

[0033] 3, in this embodiment, the upper edge of the side plate 24 is positioned at the same height as or approximately at the same height as the lower end 15b of the outlet 15a of the air supply duct 15. In other embodiments, the upper edge of the side plate 24 may be lower than the lower end 15b of the outlet 15a.

[0034] 4 is a schematic plan view showing the scraper unit 20 according to this embodiment, viewed from above. In FIG. 4, the rotation direction of the table 2 is indicated by an arrow R. The side plate 24 extends in the circumferential and axial directions and faces the side wall 17a of the primary air chamber 17. The side plate 24 is disposed so that a slight step is formed between the side plate 24 and the radially outer end face of the scraper 22 in the radial direction.

[0035] 3, for example, the side plate 24 is inclined relative to the vertical direction so that the upper edge of the side plate 24 is positioned radially inward relative to the lower edge. In other embodiments, the side plate 24 may be parallel to the vertical direction.

[0036] 2, the side edge of the side plate 24 that is closest to the scraper 22 is inclined relative to the vertical direction so that the side edge is linearly or substantially linearly continuous with the scraper 22. For example, the side plate 24 has a substantially trapezoidal shape when viewed from the radial direction.

[0037] For example, the top plate 25 is connected to the upper edge of the scraper 22 via a connecting plate 26. The top plate 25 is also connected to the upper edge of the side plate 24. The top plate 25 is disposed at a position higher than the upper edge of the scraper 22. The top plate 25 is also disposed at the same height as the upper edge of the side plate 24. The top plate 25 extends in the circumferential direction and the radial direction. The top plate 25 is spaced apart from the floor surface 17b of the primary air chamber 17 and faces the floor surface 17b.

[0038] 3, in this embodiment, the top plate 25 is disposed at the same height as or approximately the same height as the lower end 15b of the outlet 15a of the air supply duct 15. In other embodiments, the top plate 25 may be disposed at a height lower than the lower end 15b of the outlet 15a. Referring to FIG. 4, for example, the top plate 25 has a generally trapezoidal shape when viewed in the vertical direction (or axial direction).

[0039] Referring to FIG. 2 , the connecting plate 26 connects the side plate 24 and the top plate 25 to the scraper 22. Specifically, the connecting plate 26 is inclined relative to the vertical direction so that the connecting plate 26 is linearly or substantially linearly continuous with the scraper 22. When viewed in the circumferential direction, the connecting plate 26 has a substantially rectangular shape. The lower edge of the connecting plate 26 is connected to the upper edge of the scraper 22, and the upper edge of the connecting plate 26 is connected to the edge of the top plate 25 closest to the scraper 22. Furthermore, the radially outer side edge of the connecting plate 26 is connected to the side edge of the side plate 24 closest to the scraper 22.

[0040] The side plates 24, the top plate 25, and the connecting plate 26 are connected to one another so that no gaps are formed between them. For example, the side plates 24, the top plate 25, and the connecting plate 26 may be formed by bending a single metal plate and connecting adjacent edges by welding, or by welding three separate metal plates together. However, the side plates 24, the top plate 25, and the connecting plate 26 are not limited to these and may be formed by other methods. For example, the connecting plate 26 can be fixed to the scraper 22 by various methods, such as bolts, welding, or adhesives.

[0041] The russell plate 23 smooths out foreign matter accumulated on the floor surface 17b before the foreign matter is scraped up by the scraper 22. The russell plate 23 is disposed at a distance from the scraper 22 on the forward side in the rotation direction R. The russell plate 23 is supported by the base 21, which rotates integrally with the table 2, and therefore rotates integrally with the table 2 and the scraper 22.

[0042] 4, the raschel plate 23 is disposed at an angle relative to the scraper 22 in a plan view. For example, the scraper 22 is parallel or approximately parallel to the radial direction in a plan view. In contrast, the raschel plate 23 is inclined relative to the radial direction in a plan view. More specifically, the distance L from the radially outer end of the scraper 22 to the radially outer end of the raschel plate 23 is greater than the distance A from the radially outer end of the scraper 22 to the forward end of the top plate 25.

[0043] For example, in this embodiment, the Russell plate 23 is shorter in the radial direction than the scraper 22. Therefore, in this embodiment, the side plate 24 does not overlap with the Russell plate 23 in the radial direction.

[0044] FIG. 5 is a schematic front view of the scraper unit 20 according to the embodiment, as viewed from the radially inner side. The lower edge of the raschel plate 23 is spaced apart from the floor surface 17b of the primary air chamber 17. More specifically, in this embodiment, the height from the floor surface 17b to the lower edge of the raschel plate 23 is equal to the height from the floor surface 17b to the lower edge of the side plate 24. This configuration prevents, for example, large foreign objects that are repelled radially outward by the raschel plate 23 from becoming lodged between the side plate 24 and the floor surface 17b. In other embodiments, the height from the floor surface 17b to the lower edge of the raschel plate 23 may be lower or higher than the height from the floor surface 17b to the lower edge of the side plate 24.

[0045] The crusher 100 described above includes a rotating table 2, a primary air chamber 17 defined below the table 2, an air intake duct 15 having an outlet 15a in a sidewall 17a of the primary air chamber 17, the outlet 15a being spaced apart from a floor 17b of the primary air chamber 17, a scraper 22 disposed along the floor 17b and rotating around the rotation axis of the table 2, the scraper 22 extending radially outward relative to the rotation axis, and a top plate 25 connected to the radially outer end of the scraper 22 on the forward side in the rotation direction R and positioned opposite the floor 17b. The top plate 25 is positioned at a height equal to or lower than the lower end 15b of the outlet 15a. With this configuration, foreign matter collected by the scraper 22 is moved radially outward by centrifugal force. However, the top plate 25 is provided at the radially outer end of the scraper 22. This top plate 25 is positioned at a height equal to or lower than the lower end 15b of outlet 15a of air supply duct 15. Therefore, top plate 25 prevents foreign matter from accumulating beyond lower end 15b of outlet 15a. Therefore, foreign matter cannot enter outlet 15a, and accumulation of foreign matter at outlet 15a of air supply duct 15 can be suppressed.

[0046] The crusher 100 also includes a side plate 24 that is connected to the radially outer end of the scraper 22 on the forward side in the rotation direction R and faces the side wall 17a. This configuration can also block foreign matter from the sides, thereby further preventing foreign matter from entering the outlet 15a of the air supply duct 15.

[0047] Furthermore, the top plate 25 is disposed at a height higher than the upper edge of the scraper 22, and the crusher 100 includes a connecting plate 26 that connects the top plate 25 to the upper edge of the scraper 22. With this configuration, the top plate 25 can be disposed at a higher position. This increases the space for temporarily retaining foreign matter, preventing the foreign matter from overflowing from the top plate 25. Furthermore, the connecting plate 26 can prevent the foreign matter from leaking backward in the rotation direction R from the scraper 22 and the top plate 25.

[0048] The crusher 100 also includes a Russell plate 23 that is spaced apart from the scraper 22 on the forward side in the rotation direction R and rotates integrally with the scraper 22. The Russell plate 23 is tilted relative to the scraper 22 in a plan view, and the distance L from the radially outer end of the scraper 22 to the other end of the Russell plate 23 is greater than the distance A from the radially outer end of the scraper 22 to the forward end of the top plate 25. With this configuration, the Russell plate 23 is tilted significantly radially inward, making it easier for foreign matter to collect radially inward. This can slow the radially outward movement of foreign matter due to centrifugal force.

[0049] From another perspective, the crusher 100 includes a rotating table 2, a primary air chamber 17 defined below the table 2, a scraper 22 disposed along a floor surface 17b of the primary air chamber 17 and rotating around the center of rotation of the table 2, the scraper 22 extending radially outward from the center of rotation, a side plate 24 connected to the radially outer end of the scraper 22 on the forward side in the rotation direction R and facing the side wall 17a of the primary air chamber 17, and a top plate 25 connected to the radially outer end of the scraper 22 on the forward side in the rotation direction R and facing the floor surface 17b of the primary air chamber 17. With this configuration, foreign matter collected by the scraper 22 is moved radially outward by centrifugal force. However, the side plate 24 blocks the foreign matter moving radially outward. Additionally, top plate 25 blocks foreign matter that climbs over scraper 22 and side plate 24. Therefore, foreign matter cannot move radially outward from side plate 24, and accumulation of foreign matter at outlet 15a of air supply duct 15 can be suppressed.

[0050] Although the embodiments have been described above with reference to the accompanying drawings, the present disclosure is not limited to the above-described embodiments. It is clear that a person skilled in the art can conceive of various modifications or alterations within the scope of the claims, and it is understood that such modifications also fall within the technical scope of the present disclosure.

[0051] For example, in the above embodiment, the grinder 100 includes both the side plates 24 and the top plate 25. In other embodiments, the grinder 100 may include only the top plate 25.

[0052] Also, for example, in the above embodiment, outlet 15a of air supply duct 15 is spaced from floor surface 17b of primary air chamber 17, and top plate 25 is disposed at a height equal to or lower than lower end 15b of outlet 15a. However, for example, in an embodiment including both side plate 24 and top plate 25, lower end 15b of outlet 15a may be located at the same height as floor surface 17b. Also, in an embodiment including both side plate 24 and top plate 25, top plate 25 may be disposed at a height higher than lower end 15b of outlet 15a.

[0053] This disclosure can promote better energy supply through better facilities, thereby contributing to Goal 7 of the United Nations-led Sustainable Development Goals (SDGs), "Ensure access to affordable, reliable, sustainable and modern energy." [Explanation of symbols]

[0054] 2 tables 15 Air supply duct 15a Air supply duct outlet 15b Bottom of the exit 17 Primary air chamber 17a side wall 17b Floor surface 22 Scraper 23 Russell Plate 24 Side Plate 25 Top Plate 26 Connecting plate 100 Crusher R Rotation direction

Claims

1. A rotating table and an air chamber defined below the table; an air supply duct having an outlet on a side wall of the air chamber, the outlet being spaced apart from a floor surface of the air chamber; a scraper disposed along the floor surface and rotating around a rotation axis of the table, the scraper extending radially outward relative to the rotation axis; a top plate connected to the radially outer end of the scraper on the forward side in the rotational direction and arranged to face the floor surface, the top plate being arranged at a height equal to or lower than the lower end of the outlet; A crusher comprising:

2. The crusher according to claim 1 , further comprising a side plate connected to the radially outer end of the scraper on the forward direction side in the rotational direction and facing the side wall.

3. The top plate is disposed at a height higher than an upper edge of the scraper, 3. The pulverizer of claim 1, further comprising a connecting plate connecting the top plate to the upper edge of the scraper.

4. a Russell plate disposed on the forward side of the rotation direction of the scraper at a distance from the scraper and rotating integrally with the scraper; 3. The crusher according to claim 1, wherein the Russell plate is disposed at an angle to the scraper in a plan view, and a distance from the radially outer end of the scraper to the radially outer end of the Russell plate is greater than a distance from the radially outer end of the scraper to a forward-moving end of the top plate.

5. a Russell plate disposed on the forward side of the rotation direction of the scraper at a distance from the scraper and rotating integrally with the scraper; 4. The crusher according to claim 3, wherein the Russell plate is disposed at an angle relative to the scraper in a plan view, and a distance from the radially outer end of the scraper to the radially outer end of the Russell plate is greater than a distance from the radially outer end of the scraper to a forward-moving end of the top plate.

6. A rotating table and an air chamber defined below the table; a scraper disposed along a floor surface of the air chamber, rotating around a rotation center of the table, and extending radially outward from the rotation center; a side plate connected to a radially outer end of the scraper on the forward direction side in the rotational direction and facing a side wall of the air chamber; a top plate connected to the radially outer end of the scraper on the forward direction side in the rotation direction and disposed so as to face the floor surface of the air chamber; A crusher comprising:

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