A stirred mill with heterodirectional stirring

Abstract

The application discloses a kind of stirring mills of heterodirectional stirring, including grinding cylinder, feeding port, discharge port, mill air inlet, mill air outlet, stirring shaft, stirrer, driving device, separation device and cooling device;Grinding cylinder is close to the stirrer on the stirring shaft and is set in feeding end, and separation device is set on the stirring shaft close to discharge end;Cooling device is arranged on the periphery of grinding cylinder;Stirrer is divided into forward stirrer and reverse stirrer, and forward stirrer and reverse stirrer are evenly arranged in sequence along the stirring shaft, and forward stirrer is fixed on the stirring shaft, and reverse stirrer is installed on the stirring shaft by coaxial direction-changing transmission mechanism, so that forward and reverse stirrers are rotated in different directions under the action of stirring shaft and coaxial direction-changing transmission mechanism;The separation device is a hollow hemispherical structure, and is a hole distance adjustable type separation device.The application can greatly improve the grinding efficiency of dry method stirring mill, flexibly control the fineness of product from mill, and improve the reliability and stability of equipment.

Description

A type of counter-rotating stirred mill Technical Field

[0001] This invention relates to the field of stirred mill technology, and in particular to a stirred mill with counter-rotating stirring. Background Technology

[0002] A stirred mill is a fine grinding device widely used in mining, pigment, chemical, building materials, and pharmaceutical industries. It consists of a drive unit, a cylinder, a stirring shaft, an agitator, and grinding media. The cylinder is typically cylindrical, and the agitator is usually of three types: spiral, pin-type, and disc-type. The grinding media are typically steel balls, corundum balls, zirconium balls, or spherical media such as natural river sand and pebbles. During operation, the stirred mill cylinder is stationary. The drive unit drives the stirring shaft, which in turn rotates the agitator. The agitator directly applies power to the grinding media, causing the grinding media and materials to undergo multi-dimensional cyclic and rotational motions. This creates a significant velocity gradient within the cylinder, achieving effective grinding of the material through the extrusion pressure, a small amount of impact force, friction, and shear force between the grinding media. Particle grinding primarily relies on friction grinding. Extrusion pressure and impact force mainly affect the initial grinding effect, while friction and shear force determine the fine grinding efficiency. Therefore, increasing the friction and shear force between the grinding media can effectively improve the fine grinding efficiency. According to the grinding environment, stirred mills can be divided into dry mills and wet mills; according to the structural form, stirred mills can be divided into horizontal mills and vertical mills.

[0003] Currently, wet stirred mills have been scaled up and widely used, while dry stirred mills are relatively small in size and are in the stage of gradual promotion and application. The following problems exist in their application:

[0004] (1) Existing dry stirred mills have weak movement of materials and grinding media inside the mill, and the friction and shear force generated between the grinding media are small. The grinding zone is mainly concentrated near the stirring plate and near the inner wall of the cylinder, resulting in poor grinding effect and low grinding efficiency.

[0005] (2) In the existing dry stirred mill, the grinding media inside the mill is subjected to the action of the stirrer and makes a circular motion in the same clockwise direction on the cross-section of the mill. With the vertical diameter as the boundary, the grinding media on one side makes an upward motion and the grinding media on the other side makes a downward motion. Under the action of gravity, the kinetic energy of the grinding media making a downward motion is higher than that of the grinding media making an upward motion. This causes the grinding media making a downward motion to have a large impact on one side of the cylinder wall, causing the mill to vibrate and reducing the reliability of the mill.

[0006] (3) Existing dry stirred mills lack effective measures to control the fineness of the discharged material. The fineness control of the discharged material is not flexible enough. At the same time, qualified products cannot be discharged in time, resulting in serious over-grinding of local materials. This also reduces the stability of the equipment and limits the size of the equipment.

[0007] (4) Existing dry stirred mills generate a lot of heat during the grinding process, posing safety hazards such as high temperature burns and dust explosions, and lack flexible and effective heat dissipation measures. Summary of the Invention

[0008] To address the problems of low grinding efficiency, poor equipment reliability, inflexible control of output fineness, and difficulty in heat dissipation in existing dry stirred mills, this invention provides a counter-directional stirring mill. This stirred mill can significantly improve the grinding efficiency of dry stirred mills, flexibly control the fineness of the output product, and enhance equipment reliability and stability.

[0009] This invention is implemented as follows: a counter-rotating stirred mill includes a grinding cylinder, a feed inlet, a discharge outlet, a mill air inlet, a mill air outlet, a stirring shaft, a stirrer, a drive unit, a separation unit, and a cooling unit. The grinding cylinder is supported and fixed by a foundation and a bracket. One end of the grinding cylinder is provided with a feed inlet and a mill air inlet, and the other end is provided with a discharge outlet and a mill air outlet. The grinding cylinder is filled with grinding media. A stirrer is installed on the stirring shaft near the feed end inside the grinding cylinder, and a separation unit is installed on the stirring shaft near the discharge end for separating the ground material from the grinding media. One end of the stirring shaft is connected to the drive unit, and the other end passes through the grinding cylinder along the axis of the grinding cylinder and is supported by a bearing installed on the foundation and bracket. A cooling unit is provided around the grinding cylinder.

[0010] The stirrer is divided into a forward stirrer and a reverse stirrer. The forward stirrer and the reverse stirrer are arranged alternately and evenly along the stirring shaft. The forward stirrer is fixed on the stirring shaft, and the reverse stirrer is installed on the stirring shaft through a coaxial direction-changing transmission mechanism, so that the forward and reverse stirrers can rotate in different directions under the action of the stirring shaft and the coaxial direction-changing transmission mechanism.

[0011] The separation device has a hollow hemispherical structure and is an adjustable hole spacing separation device, which allows for controllability of the sieve hole size and sieve area.

[0012] The drive unit rotates the stirring shaft, which in turn drives the forward agitator to rotate in the same direction as the shaft. Simultaneously, it drives the coaxial reversing transmission mechanism mounted on the stirring shaft, which in turn drives the reverse agitator to rotate in the opposite direction. Material is fed into the grinding drum, where it undergoes multi-dimensional cyclic and rotational motion with the grinding media under the high-speed rotation of the two agitators. The material particles are crushed by the grinding media, primarily through friction and shear forces. Cold air enters the mill inlet, and the material gradually moves to the discharge end under the influence of the airflow and agitation. Then, it passes through an adjustable-aperture separator to separate the qualified particle size product from the grinding media. The grinding media is blocked by the separator and remains inside the grinding drum, while the finely ground material is discharged through the separator. The adjustable-aperture separator allows for flexible adjustment of the sieve aperture, thereby adjusting the grinding time within the mill by adjusting the discharge speed, and flexibly regulating the fineness of the discharged product. The qualified product discharged from the separator exits through the discharge port. The cold air introduced into the grinding cylinder passes through the separation device and is discharged through the air outlet above the discharge port. A cooling device is installed on the outer wall of the grinding cylinder to ensure continuous cooling during long-term operation of the equipment.

[0013] Preferably, the coaxial reversing transmission mechanism comprises a stirring shaft bevel gear, two reversing transmission bevel gears, a hollow shaft bevel gear, a hollow shaft, and a sealing cover. The stirring shaft bevel gear is fixed to the stirring shaft, and the two reversing transmission bevel gears are symmetrically arranged on both sides of the stirring shaft and mesh with the stirring shaft bevel gear at a 90° angle. The hollow shaft bevel gear is fixed to the hollow shaft and meshes with the two reversing transmission bevel gears at a 90° angle. Both ends of the hollow shaft are coaxially mounted on the stirring shaft via hollow shaft bearings. Each reversing transmission bevel gear is rotatably supported by a gear seat installed inside the sealing cover. The stirring shaft bevel gear, the two reversing transmission bevel gears, and the hollow shaft bevel gear are all sealed inside the sealing cover. Both ends of the sealing cover are connected to the stirring shaft and the hollow shaft via sealing cover bearings. The reverse stirrer is fixed to the hollow shaft located outside the sealing cover. Under the action of the coaxial reversing transmission mechanism, the hollow shaft rotates in the opposite direction to the stirring shaft, driving the reverse stirrer to rotate in the opposite direction.

[0014] Preferably, the small-diameter end of the adjustable-hole-pitch separation device is detachably fixed to the stirring shaft, and the large-diameter end forms a labyrinth seal with the grinding cylinder; the adjustable-hole-pitch separation device consists of an outer sieve plate and an inner sieve plate, the inner sieve plate is placed inside the outer sieve plate and fits against the outer sieve plate, the outer sieve plate is detachably mounted on the stirring shaft and rotates with the shaft, and the inner sieve plate can rotate relative to the outer sieve plate; each sieve plate surface has circular or elongated sieve holes, the opening position and shape of the inner and outer sieve plates are consistent, and the diameter or width of the sieve holes is 0.5 to 0.9 times the diameter of the grinding media.

[0015] Further preferably, the outer sieve plate has an annular sealing plate at its large-diameter edge, the annular sealing plate having an "L"-shaped cross-section. An annular sealing ring with a U-shaped sealing groove is provided on the inner wall of the grinding cylinder. A plate parallel to the axial direction in the annular sealing plate mates with the annular sealing ring to form a sealing area. The inner sieve plate has a fastening ring at its large-diameter edge, with multiple arc-shaped elongated through holes evenly spaced along the circumference. Multiple fixed threaded posts for engaging with the arc-shaped elongated through holes are evenly spaced along the circumference on a plate perpendicular to the axial direction in the annular sealing plate. The diameter of the fixed threaded posts matches the width of the arc-shaped elongated through holes. The fixed threaded posts can move within the arc-shaped elongated through holes, allowing the inner sieve plate to rotate relative to the outer sieve plate. The fixed threaded posts pass through the arc-shaped elongated through holes and are fastened with nuts, thus fixing the inner and outer sieve plates.

[0016] Preferably, the cooling device is a modular assembly cooling device, which is composed of multiple interconnectable cooling units. Each cooling unit is made of a flexible material with high thermal conductivity, is rectangular when laid flat, and can be bent arbitrarily. The side of the unit close to the grinding cylinder body is attached with a magnetic material that can be attached to the surface of the grinding cylinder body, so that the cooling unit can be attached to the surface of the grinding cylinder body under the action of magnetic force.

[0017] More preferably, the cooling unit includes a flexible outer shell with a sandwich layer in the middle for the flow of cooling medium. Multiple sets of heat sinks are fixed in the sandwich layer on the side closest to the grinding cylinder. Each cooling unit has multiple cooling medium inlet and outlet pipes on the edge of its flexible outer shell, which can be connected and connected with other cooling units or closed individually. Each cooling unit has a fixing hole on its edge, which is connected and fixed to a fixing joint on the surface of the grinding cylinder. The cooling unit can be made in multiple sizes, so that it can be flexibly combined and laid on the outer wall of the grinding cylinder according to the distribution and area of ​​the outer wall region.

[0018] Preferably, the forward stirrer and the reverse stirrer have the same structure, which is a disc structure. The distance between the outer edge of the stirrer and the inner wall of the grinding cylinder is 2 to 10 times the diameter of the grinding medium. The disc surface of the stirrer is uniformly provided with multiple through holes along the circumferential direction, and the total through area on the disc surface accounts for 0.2 to 0.6.

[0019] Preferably, the grinding cylinder is composed of a cylindrical body and end caps at both ends. The ratio of the length to the diameter of the cylinder is 1.5 to 4. The grinding cylinder is arranged horizontally and filled with spherical grinding media of 2 to 10 mm in diameter. The filling rate of the grinding media is 50% to 90%.

[0020] Preferably, the feeding port is located on the upper part of one end cap of the grinding cylinder, and an airlock feeding device is provided at the feeding port. The airlock feeding device causes the material to enter the grinding cylinder at an angle of 45° to 75° with the horizontal direction. The airlock feeding device includes a feeder outer shell, a feeder inner shell, an airlock plate, and a counterweight. The lower part of the feeder inner shell extends into the feeder outer shell. The airlock plate is placed inside the feeder outer shell and located below the feeder inner shell. The airlock plate is fixedly connected to the counterweight and is mounted on the feeder outer shell through a rotating shaft. When no material passes through, the airlock plate is in contact with the bottom surface of the feeder inner shell under the action of the counterweight, blocking the feeding channel. When material passes through, the weight of the material causes the airlock plate to separate from the bottom surface of the feeder inner shell, opening the feeding channel and allowing the material to pass through smoothly.

[0021] Preferably, the discharge port is located at the bottom of the grinding cylinder.

[0022] Preferably, the air inlet of the mill is located at the upper part of the grinding cylinder and is connected to the upper wall of the grinding cylinder. The air inlet direction forms an angle of 15° to 45° with the horizontal direction. Air holes are evenly opened on the wall of the grinding cylinder in the ventilation area. The diameter of the air holes is 0.1 to 0.9 times the diameter of the grinding media.

[0023] Preferably, the mill outlet is located on the upper part of the discharge side end cover of the grinding cylinder, the mill outlet is horizontally arranged, and the downstream of the mill outlet is connected to the dust collection equipment.

[0024] Preferably, the drive device is located at one end of the feeding side of the grinding cylinder and adopts a permanent magnet direct drive or a motor plus a reducer drive method.

[0025] The present invention has the following advantages and beneficial effects:

[0026] 1) The agitator of this invention is divided into a forward agitator and a reverse agitator, arranged coaxially in a staggered manner. Under the action of the coaxial direction-changing transmission mechanism, adjacent agitators can achieve opposite rotation. Each agitator drives the nearby grinding media to perform a circular motion in the same direction, so that the grinding media between adjacent agitators present opposite circular motion directions. On the one hand, the difference in the motion direction of the grinding media increases the shear force and friction between the grinding media, causing the material to be subjected to greater shear and friction, making it easier to be crushed. From the perspective of the grinding mechanism, this improves the grinding efficiency and facilitates fine grinding of materials. On the other hand, the difference in the motion direction of the grinding media balances the impact force of the falling grinding media on both sides of the cylinder, avoiding the mill vibration caused by the impact of the falling grinding media on one side of the cylinder when the grinding media move in the same direction, thus improving the reliability of the mill.

[0027] 2) The coaxial reversing transmission mechanism of the present invention can transmit torque opposite to the rotation direction of the stirring shaft, so that adjacent coaxial stirrers can rotate in different directions.

[0028] 3) The adjustable aperture separation device of the present invention adopts a hollow hemispherical form, which has a larger material contact area and a larger screening area compared with other types of separation devices, which is conducive to the discharge of qualified products. At the same time, the double-layer screen plate structure can adjust the screen hole size of the entire device by rotating the inner screen plate so that the solid area of ​​the inner screen plate blocks the screen hole of the outer screen plate, thereby achieving a flexible and adjustable overall screening area. This allows for control of the material discharge speed, adjustment of the material residence time in the mill, and control of product fineness.

[0029] 4) The modular cooling device of this invention is composed of multiple cooling units. Each cooling unit has a jacket for the flow of cooling medium, which allows for rapid heat dissipation and can be bent and attached to the surface of the cylinder. Individual cooling units can be made in multiple sizes and can be flexibly combined and laid on the outer wall of the mill cylinder according to the area of ​​the outer wall region, with interconnections, to achieve overall cooling of the cylinder. The modular cooling device is flexible in configuration, easy to maintain and replace, and avoids the problem of cooling medium seeping into the equipment.

[0030] 5) The dry stirring mill of the present invention can improve the grinding efficiency of the dry stirring mill, flexibly control the fineness of the milled product, and improve the reliability and stability of the equipment. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the specific embodiments of the present invention, the drawings used in the description of the specific embodiments will be briefly introduced below. Obviously, the drawings described below are some specific embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0032] Figure 1 is a schematic diagram of the external structure of the anti-directional stirring mill provided in an embodiment of the present invention;

[0033] Figure 2 is a schematic diagram of the internal structure of the anti-directional stirring mill provided in an embodiment of the present invention;

[0034] Figure 3 is a schematic diagram of the airlock feeding device provided in an embodiment of the present invention;

[0035] Figure 4 is a schematic diagram of the structure of the stirrer provided in an embodiment of the present invention;

[0036] Figure 5 is a structural schematic diagram of the coaxial reversing transmission mechanism provided in an embodiment of the present invention;

[0037] Figure 6 is a schematic diagram of the adjustable hole spacing separation device provided in an embodiment of the present invention;

[0038] Figure 7 is a schematic diagram of the cooling unit of the combined assembled cooling device provided in an embodiment of the present invention.

[0039] In the diagram: 1. Grinding cylinder; 2. Airlock feeding device; 2-1. Feeder outer shell; 2-2. Feeder inner shell; 2-3. Airlock plate; 2-4. Rotating shaft; 2-5. Counterweight; 3. Discharge port; 4. Drive device; 5. Agitator shaft; 6. Foundation and support; 7. Mill air inlet; 8. Mill air outlet; 9. Modular cooling device; 9-1. Flexible outer shell; 9-2. Heat sink; 9-3. Cooling medium inlet and outlet pipes; 9-4. Fixing hole; 10. Coaxial reversing transmission mechanism; 10-1. Agitator shaft umbrella type 10-2. Gear; 10-3. Hollow shaft bevel gear; 10-4. Reversing transmission bevel gear; 10-5. Gear seat; 10-6. Sealing cover; 10-7. Hollow shaft bearing; 10-8. Sealing cover bearing; 11. Forward agitator; 12. Reverse agitator; 13. Adjustable hole spacing separation device; 13-1. Outer sieve plate; 13-2. Inner sieve plate; 13-3. Annular sealing plate; 13-4. Fixed threaded post; 13-5. Fastening ring; 13-6. Nut; 14. Annular sealing ring. Detailed Implementation

[0040] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0042] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0043] Example

[0044] Please refer to Figures 1 to 7. An embodiment of the present invention provides a stirring mill with counter-directional stirring, including a grinding cylinder 1, a feed port, a discharge port 3, a mill air inlet 7, a mill air outlet 8, a stirring shaft 5, a stirrer, a drive device 4, a separation device, and a cooling device.

[0045] The grinding cylinder 1 is supported and fixed by the foundation and bracket 6. One end of the grinding cylinder 1 is provided with a feeding port and a mill air inlet 7, and the other end is provided with a discharge port 3 and a mill air outlet 8. The grinding cylinder 1 is filled with grinding media. A stirrer is provided on the stirring shaft 5 near the feeding end inside the grinding cylinder 1, and a separation device for separating the ground material from the grinding media is provided on the stirring shaft 5 near the discharge end. The stirring shaft 5 is a high-speed shaft. One end of the stirring shaft 5 is connected to the drive device 4, and the other end passes through the grinding cylinder 1 along the axis of the grinding cylinder 1 and is supported by a bearing installed on the foundation and bracket 6.

[0046] The grinding cylinder 1 consists of a cylindrical body and end caps at both ends. The length-to-diameter ratio of the cylinder is 1.5 to 4. The grinding cylinder 1 is horizontally arranged and filled with spherical grinding media of 2 to 10 mm in diameter, with a grinding media filling rate of 50% to 90%. In this embodiment, the grinding cylinder 1 is 5000 mm long and 2500 mm in diameter, filled with 5 mm spherical grinding media, with a media filling rate of 75%.

[0047] The feeding port is located on the upper part of one end cap of the grinding cylinder 1. An airlock feeding device 2 is installed at the feeding port, which causes the material to enter the grinding cylinder 1 at an angle of 45° to 75° to the horizontal direction. The airlock feeding device 2 includes a feeder outer shell 2-1, a feeder inner shell 2-2, an airlock plate 2-3, and a counterweight 2-5. The lower part of the feeder inner shell 2-2 extends into the feeder outer shell 2-1, and the airlock plate 2-3 is placed inside the feeder outer shell 2-1 and located below the feeder inner shell 2-2. The airlock plate 2-3 is fixedly connected to the counterweight 2-5 and mounted on the feeder housing 2-1 via a rotating shaft 2-4. When no material passes through, the airlock plate 2-3, under the action of the counterweight 2-5, adheres to the bottom surface of the feeder inner housing 2-2, thus reducing the angle between the airlock plate 2-3 and the horizontal direction and blocking the feeding channel. When material passes through, the weight of the material causes the airlock plate 2-3 to separate from the bottom surface of the feeder inner housing 2-2, thus increasing the angle between the airlock plate 2-3 and the horizontal direction, opening the feeding channel and allowing the material to pass smoothly. In this embodiment, the material enters the grinding cylinder 1 at a 60° angle to the horizontal direction.

[0048] The discharge port 3 is located at the bottom of the grinding cylinder 1 to facilitate the rapid discharge of the separated material.

[0049] The mill air inlet 7 is located at the upper part of the grinding cylinder 1 and is connected to the upper wall of the grinding cylinder 1. The air inlet direction forms an angle of 15° to 45° with the horizontal direction. Air holes are evenly opened on the wall of the grinding cylinder 1 in the ventilation area. The diameter of the air holes is 0.1 to 0.9 times the diameter of the grinding media. In this embodiment, the air inlet direction forms an angle of 30° with the horizontal direction and the diameter of the air holes is 2mm. The air holes can make the air supply uniformly supplied into the grinding cylinder 1, while avoiding the interference of the grinding media on the air duct.

[0050] The mill outlet 8 is located on the upper part of the discharge side end cover of the grinding cylinder 1. The mill outlet 8 is arranged horizontally, and the downstream of the mill outlet 8 is connected to the dust collection equipment.

[0051] The drive device 4 is located at one end of the feeding side of the grinding cylinder 1, and adopts a permanent magnet direct drive or a motor plus a reducer drive method. In this example, the permanent magnet direct drive drive method is preferred.

[0052] The stirrer is divided into a forward stirrer 11 and a reverse stirrer 12. The forward stirrer 11 and the reverse stirrer 12 are arranged alternately and evenly along the stirring shaft 5. The forward stirrer 11 is fixed on the stirring shaft 5 and rotates in the same direction as the stirring shaft 5. The reverse stirrer 12 is installed on the stirring shaft 5 through a coaxial direction-changing transmission mechanism 10, so that the forward and reverse stirrers can rotate in different directions under the action of the stirring shaft 5 and the coaxial direction-changing transmission mechanism 10.

[0053] The coaxial reversing transmission mechanism 10 consists of a stirring shaft bevel gear 10-1, two reversing transmission bevel gears 10-4, a hollow shaft bevel gear 10-2, a hollow shaft 10-3, and a sealing cover 10-6. The stirring shaft bevel gear 10-1 is fixed to the stirring shaft 5 and rotates in the same direction as the stirring shaft 5. The two reversing transmission bevel gears 10-4 are symmetrically arranged on both sides of the stirring shaft 5 and mesh with the stirring shaft bevel gear 10-1 at a 90° angle. The hollow shaft bevel gear 10-2 is fixed to the hollow shaft 10-3 and meshes with the two reversing transmission bevel gears 10-4 at a 90° angle. Both ends of the hollow shaft 10-3 are coaxially mounted on the stirring shaft 5 via hollow shaft bearings 10-7, preventing the hollow shaft 10-3 from rotating with the stirring shaft 5. Each of the aforementioned reversing transmission bevel gears 10-4 is rotatably supported by gear seats 10-5 installed inside the sealing cover 10-6. The stirring shaft bevel gear 10-1, the two reversing transmission bevel gears 10-4, and the hollow shaft bevel gear 10-2 are all sealed inside the sealing cover 10-6. The two ends of the sealing cover 10-6 are respectively connected to the stirring shaft 5 and the hollow shaft 10-3 through the sealing cover bearings 10-8. The sealing cover 10-6 does not rotate with the two shafts. The sealing cover 10-6 has a cylindrical structure. The reverse stirrer 12 is fixed on the hollow shaft 10-3 located outside the sealing cover 10-6. Under the action of the coaxial reversing transmission mechanism 10, the hollow shaft 10-3 rotates in the opposite direction to the stirring shaft 5, driving the reverse stirrer 12 to rotate in the opposite direction. Driven by the stirring shaft 5, the stirring shaft bevel gear 10-1 rotates, which in turn drives the two meshing reversing transmission bevel gears 10-4 to rotate, transmitting the opposite rotation direction to the hollow shaft bevel gear 10-2. The hollow shaft bevel gear 10-2 then drives the hollow shaft 10-3 and the reverse agitator 12 on the hollow shaft 10-3 to rotate in the opposite direction to the stirring shaft 5. All gears of the coaxial reversing transmission mechanism 10 are sealed within a cylindrical sealing cover 10-6 to protect each gear and ensure stable operation.

[0054] The forward stirrer 11 and the reverse stirrer 12 have the same structure, which is a disc-shaped structure. The distance between the outer edge of the stirrer and the inner wall of the grinding cylinder 1 is 2 to 10 times the diameter of the grinding media. Multiple through holes are evenly arranged on the disc surface of the stirrer along the circumferential direction, and the total through area on the disc surface accounts for 0.2 to 0.6 times the total area. In this embodiment, the distance between the stirrer and the inner wall of the grinding cylinder 1 is 30 mm, that is, the stirrer diameter is 2440 mm, and the through area on the stirrer disc surface is 1.8 m². 2 .

[0055] The separation device has a hollow hemispherical structure, and the sieve plate is in the form of a hollow hemispherical shape, which has a larger contact area with the material compared with other forms; and it is a separation device 13 with adjustable hole spacing, so that the size of the sieve hole and the screening area can be adjusted.

[0056] The small-diameter end of the adjustable-hole-pitch separation device 13 is detachably fixed to the stirring shaft 5, and the large-diameter end forms a labyrinth seal with the grinding cylinder 1 to prevent the grinding medium from passing through. The adjustable-hole-pitch separation device 13 consists of an outer sieve plate 13-1 and an inner sieve plate 13-2. The inner sieve plate 13-2 is placed inside the outer sieve plate 13-1 and fits against the outer sieve plate 13-1. The outer sieve plate 13-1 is detachably installed on the stirring shaft 5 and rotates with the shaft. Specifically, the small end of the outer sieve plate 13-1 has an annular support for fixing to the stirring shaft 5. The fixing method is a detachable fixing using keyways, bolts, etc. The inner sieve plate 13-2 is rotatable relative to the outer sieve plate 13-1; each sieve plate surface has circular or elongated sieve holes, and the positions and shapes of the holes on the inner sieve plate 13-2 and the outer sieve plate 13-1 are consistent. The diameter or width of the sieve holes is 0.5 to 0.9 times the diameter of the grinding media. In this embodiment, elongated sieve holes are used, and the width of the sieve holes is 3 mm.

[0057] The outer sieve plate 13-1 has an annular sealing plate 13-3 at its large-diameter edge. The cross-section of the annular sealing plate 13-3 is "L" shaped. An annular sealing ring 14 is provided on the inner wall of the grinding cylinder 1. The annular sealing ring 14 has a U-shaped sealing groove. The plate parallel to the axial direction in the annular sealing plate 13-3 cooperates with the annular sealing ring 14 to form a sealing area to prevent the grinding medium from passing through. The inner sieve plate 13-2 has a fastening ring 13-5 at its large-diameter edge. Multiple arc-shaped strips are evenly distributed along the circumference of the fastening ring 13-5. The annular sealing plate 13-3 has a through hole. Multiple threaded posts 13-4 are evenly arranged circumferentially on the plate perpendicular to the axial direction to engage with the arc-shaped through hole. The diameter of the threaded posts 13-4 matches the width of the arc-shaped through hole. The threaded posts 13-4 can move within the arc-shaped through hole, allowing the inner screen plate 13-2 to rotate relative to the outer screen plate 13-1. The threaded posts 13-4 pass through the arc-shaped through hole and are fastened with nuts 13-6, thus fixing the inner screen plate 13-2 and the outer screen plate 13-1. During installation, the threaded posts 13-4 of the outer screen plate 13-1 pass through the arc-shaped through hole of the inner screen plate 13-2 and are then fastened with nuts 13-6. By adjusting the relative position of the fixed threaded column 13-4 and the arc-shaped elongated through hole, the inner sieve plate 13-2 can rotate relative to the outer sieve plate 13-1. The solid area of ​​the inner sieve plate 13-2 blocks the sieve holes of the outer sieve plate 13-1, thereby reducing the overall screening area.

[0058] A cooling device is provided around the periphery of the grinding cylinder 1. The cooling device is a modular assembly cooling device 9, which is composed of multiple interconnectable cooling units. Each cooling unit is made of a flexible material with high thermal conductivity, such as aluminum-based composite material. When laid flat, it is rectangular and can be bent arbitrarily. The side of the unit closest to the grinding cylinder 1 is attached with a magnetic material that can be adhered to the surface of the grinding cylinder 1, so that the cooling unit can adhere to the surface of the grinding cylinder 1 under the action of magnetic force, ensuring the heat conduction effect.

[0059] The cooling unit includes a flexible outer shell 9-1 with a sandwich layer in the middle for the flow of cooling medium. Multiple sets of heat sinks 9-2 are fixed to the side of the sandwich layer closest to the grinding cylinder 1 to increase the heat dissipation area. Each cooling unit has multiple cooling medium inlet and outlet pipes 9-3 along its edge, which can be flexibly connected to other cooling units or individually sealed. Each cooling unit has fixing holes 9-4 along its edge, which are connected and fixed to a fixing joint on the surface of the grinding cylinder 1. The cooling units can be made in multiple sizes, allowing for flexible combination and application onto the outer wall of the grinding cylinder 1 according to its area distribution and size, providing overall cooling for the grinding cylinder 1. This modular cooling device 9 offers flexible configuration, ease of maintenance and replacement, and avoids the problem of cooling medium seeping into the equipment.

[0060] The specific operation process of the stirred mill of the present invention is as follows:

[0061] The drive unit 4 drives the stirring shaft 5 to rotate. The stirring shaft 5 drives the forward agitator 11 on it to rotate in the same direction as the stirring shaft 5. At the same time, it drives the coaxial reversing transmission mechanism 10 set on the stirring shaft 5 to work, which in turn drives the reverse agitator 12 to rotate in the opposite direction to the stirring shaft 5. The material is fed into the grinding cylinder 1 through the airlock feeding device 2 above one end of the grinding cylinder 1. Under the high-speed rotation and stirring action of the two agitators, the material undergoes multi-dimensional cyclic motion and rotational motion. The material particles are crushed by the grinding media, which is mainly subjected to friction and shear force. Cold air is introduced through the mill inlet 7 on the feeding end side. The material gradually moves to the discharge end under the influence of wind and agitation. Then, it is separated from the grinding media by an adjustable-aperture separator 13. The grinding media is blocked by the separator and remains inside the grinding cylinder 1, while the finely ground material is discharged through the separator. The adjustable-aperture separator 13 allows for flexible adjustment of the sieve aperture, thereby adjusting the grinding time of the material inside the mill by adjusting the discharge speed, and flexibly adjusting the fineness of the discharged product. The qualified product discharged from the separator is discharged through the discharge port 3. The cold air introduced into the grinding cylinder 1 passes through the separator and is discharged through the air outlet above the discharge port 3. A combined assembled cooling device 9 is installed on the outer wall of the grinding cylinder 1 to ensure continuous cooling during long-term operation.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A counter-rotating stirred mill, comprising a grinding cylinder, a feed inlet, a discharge outlet, a mill air inlet, a mill air outlet, a stirring shaft, a stirrer, a drive unit, a separation unit, and a cooling unit; the grinding cylinder is supported and fixed by a foundation and a bracket, one end of the grinding cylinder is provided with a feed inlet and a mill air inlet, and the other end is provided with a discharge outlet and a mill air outlet, and the grinding cylinder is filled with grinding media; a stirrer is provided on the stirring shaft near the feed end inside the grinding cylinder, and a separation unit is provided on the stirring shaft near the discharge end for separating the ground material from the grinding media; One end of the stirring shaft is connected to the drive device, and the other end passes through the grinding cylinder along the axis of the grinding cylinder and is supported by bearings mounted on the foundation and bracket; a cooling device is provided around the grinding cylinder; characterized in that: The agitator is divided into a forward agitator and a reverse agitator, which are arranged alternately and evenly along the agitation shaft. The forward agitator is fixed on the agitation shaft, and the reverse agitator is installed on the agitation shaft through a coaxial direction-changing transmission mechanism, so that the forward and reverse agitators can rotate in different directions under the action of the agitation shaft and the coaxial direction-changing transmission mechanism. The material and the grinding media undergo multidimensional cyclic motion and rotational motion under the high-speed rotation and agitation of the two agitators, and the material particles are crushed by the grinding media, which is mainly subjected to friction and shear force. The separation device is a hollow hemispherical structure with adjustable aperture spacing, allowing for control over the aperture size and sieving area. The smaller diameter end of the adjustable aperture separation device is detachably fixed to the stirring shaft, while the larger diameter end forms a labyrinth seal with the grinding cylinder. The adjustable aperture separation device consists of an outer sieve plate and an inner sieve plate. The inner sieve plate is placed inside the outer sieve plate and adheres to it. The outer sieve plate is detachably mounted on the stirring shaft and rotates with it, while the inner sieve plate can rotate relative to the outer sieve plate. An annular sealing plate with an "L"-shaped cross-section is provided at the edge of the larger diameter end of the outer sieve plate. An annular sealing ring is also provided on the inner wall of the grinding cylinder. The annular sealing ring has a U-shaped sealing groove. The plate parallel to the axial direction in the annular sealing plate cooperates with the annular sealing ring to form a sealing area. The large-diameter edge of the inner screen plate is provided with a fastening ring. Multiple arc-shaped elongated through holes are evenly opened along the circumferential direction on the fastening ring. Multiple fixed threaded posts for cooperating with the arc-shaped elongated through holes are evenly arranged along the circumferential direction on the plate perpendicular to the axial direction in the annular sealing plate. The diameter of the fixed threaded post matches the width of the arc-shaped elongated through hole. The fixed threaded post can move within the arc-shaped elongated through hole, so that the inner screen plate rotates relative to the outer screen plate. The fixed threaded post passes through the arc-shaped elongated through hole and is fastened by a nut to fix the inner screen plate and the outer screen plate.

2. The stirred mill with counter-rotating stirring according to claim 1, characterized in that, The coaxial reversing transmission mechanism consists of a stirring shaft bevel gear, two reversing transmission bevel gears, a hollow shaft bevel gear, a hollow shaft, and a sealing cover. The stirring shaft bevel gear is fixed to the stirring shaft, and the two reversing transmission bevel gears are symmetrically arranged on both sides of the stirring shaft and mesh with the stirring shaft bevel gear at a 90° angle. The hollow shaft bevel gear is fixed to the hollow shaft and meshes with the two reversing transmission bevel gears at a 90° angle. Both ends of the hollow shaft are coaxially mounted on the stirring shaft through hollow shaft bearings. Each reversing transmission bevel gear is rotatably supported by a gear seat installed inside the sealing cover. The stirring shaft bevel gear, the two reversing transmission bevel gears, and the hollow shaft bevel gear are all sealed inside the sealing cover. Both ends of the sealing cover are connected to the stirring shaft and the hollow shaft through sealing cover bearings. The reverse stirrer is fixed on the hollow shaft located outside the sealing cover. Under the action of the coaxial reversing transmission mechanism, the hollow shaft rotates in the opposite direction to the stirring shaft, driving the reverse stirrer to rotate in the opposite direction.

3. The stirred mill with counter-rotating stirring according to claim 1, characterized in that, Each sieve plate has circular or elongated sieve holes on its surface. The position and shape of the holes in the inner and outer sieve plates are the same, and the diameter or width of the sieve holes is 0.5 to 0.9 times the diameter of the grinding media.

4. The stirred mill with counter-rotating stirring according to claim 1, characterized in that, The cooling device is a modular assembly cooling device, which is composed of multiple interconnected cooling units. Each cooling unit is made of a flexible material with high thermal conductivity, is rectangular when laid flat, and can be bent arbitrarily. The side of the unit that is close to the grinding cylinder body is attached with a magnetic material that is attached to the surface of the grinding cylinder body, so that the cooling unit can be attached to the surface of the grinding cylinder body under the action of magnetic force.

5. The stirred mill with counter-rotating stirring according to claim 4, characterized in that, The cooling unit includes a flexible outer shell with a sandwich layer in the middle for the flow of cooling medium. Multiple sets of heat sinks are fixed in the sandwich layer on the side closest to the grinding cylinder. Multiple cooling medium inlet and outlet pipes are provided on the edge of the flexible outer shell of each cooling unit, which can be connected and connected to other cooling units or be closed separately. Each cooling unit has a fixing hole on its edge, which is connected and fixed to a fixing joint on the surface of the grinding cylinder. The cooling units are made in multiple sizes, so that they can be flexibly combined and laid on the outer wall of the grinding cylinder according to the distribution and area of ​​the outer wall.

6. The stirred mill with counter-rotating stirring according to claim 1, characterized in that, The forward and reverse stirrers have the same structure, which is a disc structure. The distance between the outer edge of the stirrer and the inner wall of the grinding cylinder is 2 to 10 times the diameter of the grinding medium. Multiple through holes are evenly arranged on the disc surface of the stirrer along the circumferential direction, and the total through area on the disc surface accounts for 0.2 to 0.

6.

7. The stirred mill with counter-rotating stirring according to claim 1, characterized in that, The grinding cylinder consists of a cylindrical body and end caps at both ends. The length-to-diameter ratio of the cylinder body is 1.5 to 4. The grinding cylinder is arranged horizontally and filled with spherical grinding media of 2 to 10 mm in diameter. The grinding media filling rate is 50% to 90%.

8. The stirred mill with counter-rotating stirring according to claim 1, characterized in that, The feeding port is located on the upper part of one end cap of the grinding cylinder. An airlock feeding device is provided at the feeding port. The airlock feeding device causes the material to enter the grinding cylinder at an angle of 45° to 75° with the horizontal direction. The airlock feeding device includes a feeder outer shell, a feeder inner shell, an airlock plate, and a counterweight. The lower part of the feeder inner shell extends into the feeder outer shell. The airlock plate is placed inside the feeder outer shell and located below the feeder inner shell. The airlock plate is fixedly connected to the counterweight and is mounted on the feeder outer shell through a rotating shaft. When no material passes through, the airlock plate is pressed against the bottom end face of the feeder inner shell under the action of the counterweight, blocking the feeding channel. When material passes through, its weight causes the airlock plate to separate from the bottom surface of the feeder's inner housing, opening the feeding channel and allowing the material to pass through smoothly.

9. The stirred mill with counter-rotating stirring according to claim 1, characterized in that, The discharge port is located at the bottom of the grinding cylinder.

10. The stirred mill with counter-rotating stirring according to claim 1, characterized in that, The air inlet of the mill is located at the upper part of the grinding cylinder and is connected to the upper wall of the grinding cylinder. The air inlet direction forms an angle of 15° to 45° with the horizontal direction. Air holes are evenly opened on the wall of the grinding cylinder in the ventilation area. The diameter of the air holes is 0.1 to 0.9 times the diameter of the grinding media.

11. The stirred mill with counter-rotating stirring according to claim 1, characterized in that, The mill outlet is located on the upper part of the discharge side end cover of the grinding cylinder. The mill outlet is horizontally arranged and connected to the dust collection equipment downstream of the mill outlet.

12. The stirred mill with counter-rotating stirring according to claim 1, characterized in that, The drive device is located at one end of the feeding side of the grinding cylinder and adopts a permanent magnet direct drive or a motor plus a reducer drive method.

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