A dry stirred mill with controllable material flow

Abstract

The present invention discloses a dry stirred mill with controllable material flow, comprising a grinding cylinder, a feeding port, a discharging port, a mill air inlet, a mill air outlet, a stirring shaft, an agitator, a shaft driving device, a separating device and a cooling device; an agitator is arranged on the stirring shaft near the feeding end in the grinding cylinder, and a separating device is arranged on the stirring shaft near the discharging end; a cooling device is arranged on the periphery of the grinding cylinder; the agitator is divided into a grinding agitator and a regulating agitator, the grinding agitator is fixed on the stirring shaft, and a regulating agitator is arranged every one or more grinding agitators on the stirring shaft, each regulating agitator is installed on the stirring shaft by a regulating agitator driving device, so that each regulating agitator can rotate independently in different directions and speeds to regulate the motion state of the grinding medium and material in the mill. The present invention can improve the material flow controllability of the dry stirred mill, solve the "saturated grinding" problem, reduce the starting torque, and improve the convenience of equipment maintenance and agitator disassembly.

Description

Technical Field

[0001] The invention relates to the technical field of stirred mills, in particular to a dry stirred mill with controllable material flow. Background Art

[0002] A stirred mill is a type of fine grinding equipment widely used in the mining, pigment, chemical, building materials, and pharmaceutical industries. It consists of a drive unit, a drum, agitator shaft, agitator, and grinding media. The drum is typically cylindrical, and the agitator is typically of three types: spiral, pin, or disc. The grinding media are typically spherical media such as steel balls, corundum balls, zirconium balls, or natural river sand or pebbles. During operation, the drum is stationary while the drive unit drives the agitator shaft, which rotates the agitator. The agitator applies power directly to the grinding media, causing the grinding media and the material to undergo multi-dimensional circulation and rotational motion, creating a large velocity gradient within the drum. Effective grinding of the material is achieved through extrusion between the grinding media, a small amount of impact, friction, and shear forces. Particle pulverization is primarily achieved through frictional pulverization. Extrusion and impact forces primarily affect the initial pulverization, while friction and shear determine the fine grinding efficiency. Stirred mills can be categorized as dry or wet processes based on the grinding environment, and as horizontal or vertical based on their structural form.

[0003] At present, wet stirred mills have been scaled up and widely used. 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) In the existing dry stirred mill, the material in the mill flows only by its own fluidity and the action of airflow. The controllability of the material flow is extremely weak. Its flow state and flow rate lack flexible and effective control, so it is impossible to adjust the grinding time of the material in the mill, resulting in difficulty in adjusting the fineness of the material out of the mill;

[0005] (2) In the existing dry stirred mill, when the aspect ratio of the mill barrel is too large, the material flow path is long, which easily leads to poor material flow in the mill, and the material accumulates in the mill and is difficult to discharge, which easily leads to the phenomenon of "saturated grinding";

[0006] (3) The existing dry stirred mill has a large instantaneous torque required for starting the equipment due to the accumulation and sedimentation of the grinding media during shutdown, which makes it difficult to start;

[0007] (4) The existing dry-process stirring mill has complicated disassembly and assembly of the barrel and agitator, making maintenance and replacement inconvenient. Summary of the Invention

[0008] In order to solve the problems of weak material flow controllability in existing dry stirred mills, easy "saturation grinding", large starting torque, and difficult disassembly and assembly of the agitator, the present invention provides a dry stirred mill with controllable material flow. The stirred mill can improve the material flow controllability of the dry stirred mill, solve the "saturation grinding" problem, reduce the starting torque, and improve the convenience of equipment maintenance and disassembly and assembly of the agitator.

[0009] The present invention is achieved as follows: a dry-process stirred mill with controllable material flow, comprising a grinding drum, a feed port, a discharge port, a mill air inlet, a mill air outlet, a stirring shaft, an agitator, a shaft driving device, a separating device, and a cooling device; the grinding drum is supported and fixed by a foundation and a bracket, the feeding port and the mill air inlet are provided at one end of the grinding drum, and the discharge port and the mill air outlet are provided at the other end, and the grinding drum is filled with grinding media; the agitator is provided on the stirring shaft near the feeding end of the grinding drum, and the separating device for separating the ground material and the grinding media is provided on the stirring shaft near the discharge end; one end of the stirring shaft is connected to the shaft driving device, and the other end passes through the grinding drum along the axis of the grinding drum and is supported by a bearing installed on the foundation and the bracket; a cooling device is provided on the periphery of the grinding drum;

[0010] The agitator is divided into a grinding agitator and a regulating agitator. The grinding agitator is fixed on the agitator shaft. A regulating agitator is set on the agitator shaft for every one or more grinding agitators. Each regulating agitator is installed on the agitator shaft through a regulating agitator driving device, so that each regulating agitator can rotate independently in different directions and speeds to regulate the movement state of the grinding media and materials in the mill.

[0011] Before the mill starts, each control agitator drive drives the corresponding control agitator to rotate to varying degrees, loosening the grinding media and reducing the instantaneous torque required to start the mill. The mill is then started. The shaft drive rotates the agitator shaft, which in turn drives the grinding agitator on it. The material is fed into the grinding drum and, under the high-speed stirring action of the agitator, undergoes multi-dimensional circular motion and rotation with the grinding media. The material particles are crushed by the shear force of the grinding media. Multiple control agitators, evenly spaced on the agitator shaft, rotate independently under the control of each corresponding control agitator drive. The control agitators have specific angles, and through forward and reverse rotation at different speeds, they apply axial forces in different directions to the material and grinding media, thereby regulating the flow of the material and grinding media. Cold air enters the mill's air inlet on the feed side. Driven by wind, the agitator, and its own fluidity, the material gradually moves to the discharge end. The material then passes through a separator, separating the qualified particle size from the grinding media. The grinding media is intercepted by the separator and retained within the grinding drum. The ground material can be discharged through the separator, while the qualified product discharged from the separator is discharged through the discharge port. The cold air entering the grinding drum passes through the separator and is discharged through the air outlet above the discharge port. A cooling device is installed on the outer wall of the grinding drum to ensure continuous cooling during long-term operation of the mill.

[0012] Preferably, each of the control agitators is evenly arranged, and each of the control agitators is a blade agitator, consisting of a control fixing ring and a plurality of blades, the control fixing ring is fixed on the hollow shaft of the control agitator driving device, and fixing holes are evenly distributed on the outer circumference of the control fixing ring; the blades are fixed on the control fixing ring through the fixing holes, and the blades are long strip structures with a wide head and a narrow bottom, the head of the blade is an arc shape, and a fixing seat and a bolt column are provided at the bottom of the blade, and the bolt column is connected and fixed to the fixing hole; the angle between the blade and the radial direction of the control agitator is 60°~85°, and the distance between the top of the blade and the inner wall of the grinding cylinder is 5~15 times the diameter of the grinding medium.

[0013] Preferably, the control agitator drive device consists of a hollow shaft bevel gear, a hollow shaft, a driving bevel gear, a driving shaft, a frequency conversion motor, a shaft sealing sleeve, and a sealing cover. The hollow shaft bevel gear is fixed on the hollow shaft, and the two ends of the hollow shaft are coaxially fixed on the agitator shaft through bearings; the driving bevel gear is meshed with the hollow shaft bevel gear at 90° and sealed in the sealing cover, and the two ends of the sealing cover are connected to the agitator shaft and the hollow shaft through bearings respectively; the driving shaft is arranged vertically and sealed in the shaft sealing sleeve, one end of the driving shaft is connected to the driving bevel gear, and the other end is connected to the frequency conversion motor, and rotates under the drive of the frequency conversion motor, and the frequency conversion motor is located outside the grinding cylinder; the control agitator is fixed on the hollow shaft located outside the sealing cover, and the control agitator drive device drives the control agitator to rotate.

[0014] Preferably, the grinding agitator is a disc agitator, which is a split structure and is divided into multiple annular disc bodies from the inside to the outside in the radial direction, which are a grinding fixed ring and multiple grinding stirring rings in sequence. The grinding fixed ring is fixed to the stirring shaft, and the grinding stirring ring adjacent to the grinding fixed ring and the grinding fixed ring, as well as the two adjacent grinding stirring rings, are all connected and fixed by radial bolts, so that the grinding fixed ring and each grinding stirring ring are fixedly combined in sequence to form a complete grinding agitator; each of the grinding stirring rings is divided into at least two parts.

[0015] Preferably, the distance between the outer edge of the grinding agitator and the inner wall of the grinding cylinder is 2 to 10 times the diameter of the grinding medium; a plurality of through holes are evenly arranged on the disk surface of the grinding agitator along the circumferential direction, and the total through hole area on the disk surface accounts for 0.2 to 0.6.

[0016] Preferably, the grinding cylinder consists of a cylinder and end covers at both ends, and the end covers are connected to the cylinder by bolts; the cylinder and the end covers are both split structures, each of which can be divided into multiple parts, and the parts are connected and combined by bolts.

[0017] Preferably, the ratio of the length to the diameter of the grinding cylinder is 1.5-8, and the grinding cylinder is arranged horizontally; the grinding cylinder is filled with 2-10 mm spherical grinding media, and the grinding medium filling rate is 50%-90%.

[0018] Preferably, the cooling device includes a cooling shell and heat sinks, and an interlayer is formed between the cooling shell and the grinding cylinder body, and multiple groups of heat sinks are fixed on the outer wall of the grinding cylinder body in the interlayer; multiple groups of heat sinks are also provided on the outer surface of the cooling shell; a cooling medium inlet is provided at the lower part of the cooling shell located at the discharge end side, and a cooling medium outlet is provided at the upper part of the cooling shell located at the feed end side, and the cooling medium flows in the interlayer; the cooling device is a split structure corresponding to the cylinder of the grinding cylinder.

[0019] Preferably, the separation device is a hollow hemispherical structure, the small diameter end of the separation device is detachably fixed to the stirring shaft, and the large diameter end forms a labyrinth seal with the grinding cylinder; the sieve plate surface of the separation device is provided with circular sieve holes or elongated sieve holes, and the diameter or width of the sieve holes is 0.5 to 0.9 times the diameter of the grinding medium.

[0020] Further preferably, an annular sealing plate is provided on the large diameter end edge of the sieve plate, an annular sealing ring is provided on the inner wall of the grinding cylinder, and the annular sealing plate and the annular sealing ring are plugged into each other to form a sealing area.

[0021] Preferably, the feeding port is arranged at the upper part of the end cover on one side of the grinding cylinder, and an air-locking feeding device is provided at the feeding port, and the air-locking feeding device allows the material to enter the grinding cylinder at an angle of 45°~75° to the horizontal direction; the air-locking feeding device includes a feeder outer shell, a feeder inner shell, an air-locking plate and a weight, and the lower part of the feeder inner shell extends into the feeder outer shell, and the air-locking plate is placed in the feeder outer shell and below the feeder inner shell. The air-locking plate is fixedly connected to the weight and is installed on the feeder outer shell through a rotating shaft, so that when no material passes through, the air-locking plate fits with the bottom end surface of the feeder inner shell under the action of the weight, blocking the feeding channel; when material passes through, the weight of the material separates the air-locking plate from the bottom end surface of the feeder inner shell, opens the feeding channel, and allows the material to pass smoothly.

[0022] Preferably, the discharge port is arranged at the bottom of the grinding cylinder body.

[0023] Preferably, the mill air inlet is arranged at the upper part of the grinding cylinder and 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 medium.

[0024] Preferably, the mill air outlet is arranged at the upper part of the end cover on the discharge side of the grinding cylinder, the mill air outlet is arranged horizontally, and the mill air outlet is connected to the dust collection equipment downstream.

[0025] Preferably, the shaft drive device is arranged at one end of the feeding side of the grinding cylinder and adopts a permanent magnet direct drive or a motor acceleration and reducer drive mode.

[0026] The present invention has the following advantages and beneficial effects:

[0027] 1) The control agitator of the present invention has a fixed number of grinding agitators evenly fixed on the hollow shaft. Each control agitator can rotate independently in different directions and speeds, and can control the movement state of the grinding media and materials in the mill, playing three roles: first, the flow rate of the material flow in the mill is regulated by forward and reverse rotation at different speeds, and the residence time of the material in the mill is regulated, thereby adjusting the fineness of the product; second, forward rotation can accelerate the passage of the material, which can avoid or solve the "saturation grinding" problem; third, before the mill is started, the small-amplitude forward and reverse intermittent rotation of the control agitator can loosen the grinding media and reduce the instantaneous torque required for the mill to start. Each control agitator is driven separately, and can exert different degrees and different areas of control on the grinding media and materials in the mill according to the working status. In addition, the control agitator is fixed by bolt columns, which is convenient for disassembly and maintenance.

[0028] 2) The grinding agitator of the present invention is a disc-type agitator with a split design. It is divided radially from the inside to the outside into a grinding fixed ring and multiple grinding agitating rings according to the diameter size, and is fixed in sequence by radial bolts. Each grinding agitating ring also adopts a split design, which is easy to disassemble and maintain.

[0029] 3) The grinding cylinder of the present invention is composed of a cylinder and end covers at both ends. The cylinder and the end covers are both split into multiple parts and connected by bolts, which is convenient for disassembly and maintenance of the interior of the mill.

[0030] 4) The cooling device of the present invention is arranged on the outside of the grinding cylinder body and also adopts a split design, which is consistent with the split design of the cylinder body; a sandwich is formed between the cooling shell and the cylinder body, and multiple groups of heat sinks are fixed on the outer wall of the grinding cylinder body in the sandwich. Multiple groups of heat sinks are also arranged on the outer surface of the cooling shell, which increases the heat dissipation area and improves the heat dissipation speed.

[0031] 5) The dry stirred mill with controllable material flow of the present invention can improve the material flow controllability of the dry stirred mill, solve the "saturation grinding" problem, reduce the starting torque, and improve the convenience of equipment maintenance and agitator disassembly and assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the specific embodiments of the present invention, the following is a brief introduction to the drawings required for use in the description of the specific embodiments. Obviously, the drawings described below are some specific embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0033] Figure 1 Schematic diagram of the external structure of a dry stirred mill with controllable material flow provided by an embodiment of the present invention;

[0034] Figure 2 Schematic diagram of the internal structure of a dry stirred mill with controllable material flow provided by an embodiment of the present invention;

[0035] Figure 3 2 is a schematic structural diagram of an air-locking feeding device provided in an embodiment of the present invention;

[0036] Figure 4 1 is a schematic structural diagram of a grinding and stirring device provided by an embodiment of the present invention;

[0037] Figure 5 1 is a schematic structural diagram of a control stirrer provided in an embodiment of the present invention;

[0038] Figure 6 It is a structural schematic diagram of a control stirrer driving device provided in an embodiment of the present invention.

[0039] Figure: 1. Grinding cylinder; 2. Air-locking feeding device; 2-1. Feeder outer shell; 2-2. Feeder inner shell; 2-3. Air-locking plate; 2-4. Rotating shaft; 2-5. Heavy hammer; 3. Discharge port; 4. Shaft drive device; 5. Agitator shaft; 6. Foundation and support; 7. Mill air inlet; 8. Mill air outlet; 9. Cooling device; 9-1. Cooling shell; 9-2. Heat sink; 9-3. Cooling medium inlet; 9-4. Cooling medium outlet; 10. Grinding agitator; 10-1. Grinding fixing ring; 10-2. Grinding stirring ring; 10-3. Radial bolts; 11. Control agitator; 11-1. Control fixing ring; 11-2. Blades; 12. Control agitator drive device; 12-1. Hollow shaft bevel gear; 12-2. Drive bevel gear; 12-3. Drive shaft; 12-4. Hollow shaft; 12-5. Shaft sealing sleeve; 12-6. Sealing cover; 12-7. Frequency conversion motor; 13. Separation device; 14. Annular sealing ring. DETAILED DESCRIPTION

[0040] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0041] In the description of the present invention, it should be understood that the terms "up", "down", "front", "back", "left", "right", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the present invention.

[0042] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0043] Example

[0044] See also Figures 1 to 6An embodiment of the present invention provides a dry stirred mill with controllable material flow, including a grinding cylinder 1, a feeding port, a discharge port 3, a mill air inlet 7, a mill air outlet 8, a stirring shaft 5, an agitator, a shaft driving device 4, a separating device 13 and a cooling device 9.

[0045] The grinding cylinder 1 is supported and fixed by a foundation and a bracket 6. A feeding port and a mill air inlet 7 are provided at one end of the grinding cylinder 1, and a discharge port 3 and a mill air outlet 8 are provided at the other end. The grinding cylinder 1 is filled with grinding media. An agitator is provided on the stirring shaft 5 near the feeding end of the grinding cylinder 1, and a separation device 13 for separating the ground material and 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 which is connected to the shaft 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 the bracket 6.

[0046] The grinding cylinder 1 is composed of a cylinder and end caps at both ends, and the end caps are connected to the cylinder by bolts; the cylinder and the end caps are both split structures, each of which can be divided into multiple parts, and the parts are connected and combined by bolts. Specifically, the cylinder and the end caps are respectively divided into two parts, upper and lower, in the horizontal direction, and the upper and lower parts are connected and combined by bolts, which is convenient for disassembly and maintenance of the interior of the mill. The ratio of the length to the diameter of the grinding cylinder 1 is 1.5 to 8, and the grinding cylinder 1 is arranged horizontally; the grinding cylinder 1 is filled with 2 to 10 mm spherical grinding media, and the grinding medium filling rate is 50% to 90%. In this embodiment, the grinding cylinder 1 is 7500 mm long and 2500 mm in diameter, and is filled with 5 mm spherical grinding media, and the medium filling rate is 70%.

[0047] The feeding port is arranged at the upper part of the end cover on one side of the grinding cylinder 1, and an air-locking feeding device 2 is provided at the feeding port. The air-locking feeding device 2 allows the material to enter the grinding cylinder 1 at an angle of 45°~75° with the horizontal direction; the air-locking feeding device 2 includes a feeder outer shell 2-1, a feeder inner shell 2-2, an air-locking plate 2-3 and a heavy hammer 2-5. The lower part of the feeder inner shell 2-2 extends into the feeder outer shell 2-1, and the air-locking plate 2-3 is placed in the feeder outer shell 2-1 and is located below the feeder inner shell 2-2. The air lock plate 2-3 is fixedly connected to the weight 2-5 and is mounted on the feeder outer shell 2-1 via the rotating shaft 2-4. When no material is passing through, the air lock plate 2-3, under the action of the weight 2-5, fits against the bottom end surface of the feeder inner shell 2-2, i.e., the angle between the air lock plate 2-3 and the horizontal direction decreases, blocking the feeding channel. When material is passing through, the weight of the material causes the air lock plate 2-3 to separate from the bottom end surface of the feeder inner shell 2-2, i.e., the angle between the air lock plate 2-3 and the horizontal direction increases, opening the feeding channel and allowing the material to pass smoothly. In this embodiment, the material enters the grinding cylinder 1 at an angle of 50° to the horizontal direction.

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

[0049] The mill air inlet 7 is arranged 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 medium. In this embodiment, the air inlet direction forms an angle of 30° with the horizontal direction, and the diameter of the air holes is 2 mm. The air holes can evenly supply air into the grinding cylinder 1 while avoiding interference of the grinding medium on the air duct.

[0050] The mill air outlet 8 is provided at the upper portion of the end cover on the discharge side of the grinding cylinder 1 . The mill air outlet 8 is arranged horizontally, and the downstream of the mill air outlet 8 is connected to the dust collecting equipment.

[0051] The shaft drive device 4 is arranged at one end of the feeding side of the grinding drum 1 and adopts a permanent magnet direct drive or a motor acceleration and reduction gear drive mode. In this embodiment, the permanent magnet direct drive mode is preferably adopted.

[0052] The agitator is divided into a grinding agitator 10 and a regulating agitator 11. The grinding agitator 10 is fixed on the agitator shaft 5 and rotates in the same direction as the agitator shaft 5. A regulating agitator 11 is set for every one or more grinding agitators 10 on the agitator shaft 5. In this embodiment, a regulating agitator 11 is set for every two grinding agitators 10. Each of the regulating agitators 11 is installed on the agitator shaft 5 through a regulating agitator driving device 12, so that each regulating agitator 11 can rotate independently in different directions and speeds to regulate the movement state of the grinding medium and material in the mill.

[0053] The grinding agitator 10 is a disc agitator, which is a split structure and is divided into multiple annular disc bodies from the inside to the outside in the radial direction, namely a grinding fixed ring 10-1 and multiple grinding and stirring rings 10-2. The grinding fixed ring 10-1 is fixed to the stirring shaft 5, and the grinding and stirring ring 10-2 adjacent to the grinding fixed ring 10-1 and the grinding fixed ring 10-1, as well as the two adjacent grinding and stirring rings 10-2, are connected and fixed by radial bolts 10-3. Specifically, the grinding and stirring ring 10-2 adjacent to the grinding fixed ring 10-1 is fixed to the grinding fixed ring 10-1 by radial bolts 10-3, and the large-diameter grinding and stirring ring 10-2 is fixed to the adjacent small-diameter grinding and stirring ring 10-2 by radial bolts 10-3. According to the above method, the grinding fixed ring 10-1 and each grinding and stirring ring 10-2 are fixedly combined in sequence to form a complete grinding agitator 10, which is convenient for disassembly and maintenance; each of the grinding and stirring rings 10-2 is divided into at least two parts, which is easy to disassemble and assemble.

[0054] The distance between the outer edge of the grinding agitator 10 and the inner wall of the grinding cylinder 1 is 2 to 10 times the diameter of the grinding medium; a plurality of through holes are evenly arranged on the disk surface of the grinding agitator 10 along the circumferential direction. In this embodiment, a plurality of through holes are evenly arranged on each grinding agitator ring 10-2 along the circumferential direction, and the total through area on the disk surface accounts for 0.2 to 0.6. In this embodiment, the grinding agitator 10 is divided into one grinding fixed ring 10-1 and two grinding agitator rings 10-2. The distance between the grinding agitator 10 and the inner wall of the grinding cylinder 1 is 30 mm, that is, the diameter of the grinding agitator 10 is 2440 mm, and the through area on the disk surface of the grinding agitator 10 is 1.7 m 2 .

[0055] The regulating stirrer drive device 12 is composed of a hollow shaft bevel gear 12-1, a hollow shaft 12-4, a driving bevel gear 12-2, a driving shaft 12-3, a frequency conversion motor 12-7, a shaft sealing sleeve 12-5, and a sealing cover 12-6. The hollow shaft bevel gear 12-1 is fixed on the hollow shaft 12-4, and the two ends of the hollow shaft 12-4 are coaxially fixed on the stirring shaft 5 through bearings, so that the hollow shaft 12-4 does not rotate with the stirring shaft 5; the driving bevel gear 12-2 is meshed with the hollow shaft bevel gear 12-1 at 90 degrees and is sealed in the sealing cover 12-6 to protect the gear and ensure stable operation of the gear. The two ends of the sealing cover 12-6 are respectively connected to the stirring shaft 5 and the hollow shaft 12-4 through bearings, so that the sealing cover 12-6 does not rotate with the two shafts. The sealing cover 12-6 is a cylindrical structure; the driving shaft 12-3 is arranged vertically and sealed in the shaft sealing sleeve 12-5. One end of the driving shaft 12-3 is connected to the driving bevel gear 12-2, and the other end is connected to the frequency conversion motor 12-7. It rotates under the drive of the frequency conversion motor 12-7. The frequency conversion motor 12-7 is located outside the grinding cylinder 1; the regulating stirrer 11 is fixed on the hollow shaft 12-4 located outside the sealing cover 12-6, and the regulating stirrer driving device 12 drives the regulating stirrer 11 to rotate. During operation, the variable frequency motor 12-7 drives the drive shaft 12-3 to rotate, the drive shaft 12-3 drives the drive bevel gear 12-2 to rotate, and then transmits power to the hollow shaft bevel gear 12-1, the hollow shaft bevel gear 12-1 drives the hollow shaft 12-4 and the regulating stirrer 11 on the hollow shaft 12-4 to rotate, and the speed and direction of the variable frequency motor 12-7 are adjustable.

[0056] Each of the regulating and controlling agitators 11 is evenly arranged, and each of the regulating and controlling agitators 11 is a blade-type agitator, consisting of a regulating and controlling fixing ring 11-1 and a plurality of blades 11-2. The regulating and controlling fixing ring 11-1 is fixed on the hollow shaft 12-4 of the regulating and controlling agitator driving device 12, and fixing holes are evenly distributed on the outer circumference of the regulating and controlling fixing ring 11-1; the blades 11-2 are fixed on the regulating and controlling fixing ring 11-1 through the fixing holes, and the blades 11-2 are in the shape of a long strip with a wide head and a narrow bottom. The head of the blade 11-2 is in an arc shape, and a fixing seat and a bolt column are provided at the bottom of the blade 11-2, and the bolt column is connected and fixed with the fixing hole; the angle between the blade 11-2 and the radial direction of the regulating and controlling agitator 11 is 60°~85°, and the distance between the top of the blade 11-2 and the inner wall of the grinding cylinder 1 is 5~15 times the diameter of the grinding medium. In this embodiment, the included angle between the blade 11 - 2 and the radial direction of the regulating stirrer 11 is 80°, and the distance between the blade 11 - 2 and the inner wall of the grinding cylinder 1 is 50 mm.

[0057] When working, each regulating agitator 11 can rotate independently in different directions and speeds. When rotating forward, the angled blades 11-2 can generate a thrust in the discharge direction for the material, accelerate the passage of the material, reduce the residence time of the material in the mill, and also solve the "saturation grinding" problem; when rotating reversely, the angled blades 11-2 can generate a thrust in the feed direction for the material, delay the passage of the material, and increase the residence time of the material in the mill. The degree of control of the material by the regulating agitator 11 can be adjusted by its rotation speed, and by setting different rotation states for different regulating agitators 11, targeted adjustments can be made to the material in the mill in different areas. In addition, before the mill is started, the small-amplitude forward and reverse intermittent rotation of the regulating agitator 11 can loosen the grinding medium and reduce the instantaneous torque required for the mill to start.

[0058] A cooling device 9 is provided on the periphery of the grinding cylinder 1; the cooling device 9 includes a cooling shell 9-1 and heat sinks 9-2, and an interlayer is formed between the cooling shell 9-1 and the cylindrical body of the grinding cylinder 1, and a plurality of heat sinks 9-2 are fixed on the outer wall of the cylindrical body of the grinding cylinder 1 in the interlayer to increase the heat dissipation area; a plurality of heat sinks 9-2 are also provided on the outer surface of the cooling shell 9-1 to increase the heat dissipation area and improve the heat dissipation speed; a cooling medium inlet 9-3 is provided at the lower part of the cooling shell 9-1 located at the discharge end side, and a cooling medium outlet 9-4 is provided at the upper part of the cooling shell 9-1 located at the feed end side, and the cooling medium flows in the interlayer to cool the grinding cylinder 1 as a whole and take away the heat of the mill; the cooling device 9 is a split structure corresponding to the cylinder of the grinding cylinder 1, which is consistent with the split design of the cylinder and is divided into upper and lower parts.

[0059] The separator 13 has a hollow hemispherical structure, and the sieve plate is in the form of a hollow hemispherical sieve. Compared with other structures, the contact area with the material is larger. The small-diameter end of the separator 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 passage of the grinding medium. The surface of the sieve plate of the separator 13 is provided with circular sieve holes or elongated sieve holes, and the diameter or width of the sieve holes is 0.5 to 0.9 times the diameter of the grinding medium. In this embodiment, elongated sieve holes are used, and the width of the sieve holes is 4 mm. An annular sealing plate is provided on the edge of the large-diameter end of the sieve plate, and an annular sealing ring 14 is provided on the inner wall of the grinding cylinder 1. The annular sealing plate and the annular sealing ring 14 are plugged into each other to form a sealing area to prevent the passage of the grinding medium.

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

[0061] Before the mill is started, each regulating agitator drive device 12 drives the corresponding regulating agitator 11 to rotate to different degrees, loosening the grinding medium and reducing the instantaneous torque required for the mill to start, and then the mill is started. The shaft drive device 4 drives the agitator shaft 5 to rotate, and the agitator shaft 5 drives the grinding agitator 10 thereon to rotate. The material is fed into the grinding cylinder 1 through the air-locking feeding device 2 above one end of the grinding cylinder 1, and performs multi-dimensional circulation motion and self-rotation motion with the grinding medium under the high-speed rotating stirring action of the agitator. The material particles are crushed by the grinding medium mainly with shear force. Multiple regulating agitators 11 are evenly arranged on the agitator shaft 5 at a certain distance. They rotate independently under the action of each corresponding regulating agitator drive device 12. The regulating agitator 11 has a certain angle, and exerts axial driving forces in different directions on the material and the grinding medium through forward and reverse rotation at different speeds, thereby regulating the flow state of the material and the grinding medium. Cold air is introduced into the mill's air inlet 7 on the feed side. Driven by wind power, the action of the agitator, and its own fluidity, the material gradually moves to the discharge end. Then, it passes through a separator 13 to separate the qualified particle size product from the grinding media. The grinding media is intercepted by the separator 13 and remains within the grinding drum 1. The ground material can be discharged through the separator 13, and the qualified product discharged by the separator 13 is discharged through the discharge port 3. The cold air entering the grinding drum 1 passes through the separator 13 and is discharged through the air outlet above the discharge port 3. A cooling device 9 is installed on the outer wall of the grinding drum 1 to ensure continuous cooling during long-term operation of the mill.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements 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 dry stirred mill with controllable material flow, comprising a grinding drum, a feeding port, a discharging port, a mill air inlet, a mill air outlet, a stirring shaft, an agitator, a shaft driving device, a separating device and a cooling device; the grinding drum is supported and fixed by a foundation and a bracket, the feeding port and the mill air inlet are provided at one end of the grinding drum, and the discharging port and the mill air outlet are provided at the other end, and the grinding drum is filled with grinding media; the agitator is provided on the stirring shaft near the feeding end of the grinding drum, and the separating device for separating the ground material and the grinding media is provided on the stirring shaft near the discharging end; one end of the stirring shaft is connected to the shaft driving device, and the other end passes through the grinding drum along the axis of the grinding drum and is supported by a bearing installed on the foundation and the bracket; a cooling device is provided on the periphery of the grinding drum; and the characteristics are: The agitator is divided into a grinding agitator and a regulating agitator. The grinding agitator is fixed on the agitator shaft. A regulating agitator is set on the agitator shaft for every one or more grinding agitators. Each regulating agitator is installed on the agitator shaft through a regulating agitator driving device, so that each regulating agitator can rotate independently in different directions and speeds to regulate the movement state of the grinding media and materials in the mill.

2. The dry stirred mill with controllable material flow according to claim 1, characterized in that The regulating and controlling agitators are evenly arranged, and each regulating and controlling agitator is a blade-type agitator, consisting of a regulating and controlling fixing ring and a plurality of blades. The regulating and controlling fixing ring is fixed on the hollow shaft of the regulating and controlling agitator driving device, and fixing holes are evenly distributed on the outer circumferential surface of the regulating and controlling fixing ring; the blades are fixed on the regulating and controlling fixing ring through the fixing holes, and the blades are in the shape of a long strip with a wide head and a narrow bottom. The head of the blade is in an arc shape, and a fixing seat and a bolt column are provided at the bottom of the blade, and the bolt column is connected and fixed to the fixing hole; the distance between the top of the blade head and the inner wall of the grinding cylinder is 5 to 15 times the diameter of the grinding medium.

3. The dry stirred mill with controllable material flow according to claim 1, characterized in that The regulating stirrer drive device consists of a hollow shaft bevel gear, a hollow shaft, a driving bevel gear, a driving shaft, a frequency conversion motor, a shaft sealing sleeve, and a sealing cover. The hollow shaft bevel gear is fixed on the hollow shaft, and the two ends of the hollow shaft are coaxially fixed to the stirring shaft through bearings; the driving bevel gear and the hollow shaft bevel gear are meshed at 90 degrees and sealed in the sealing cover, and the two ends of the sealing cover are respectively connected to the stirring shaft and the hollow shaft through bearings; the driving shaft is arranged vertically and sealed in the shaft sealing sleeve, one end of the driving shaft is connected to the driving bevel gear, and the other end is connected to the frequency conversion motor, and rotates under the drive of the frequency conversion motor, and the frequency conversion motor is located outside the grinding cylinder; The regulating stirrer is fixed on a hollow shaft located outside the sealing cover, and the regulating stirrer driving device drives the regulating stirrer to rotate.

4. The dry stirred mill with controllable material flow according to claim 1, characterized in that The grinding agitator is a disc-type agitator, which is a split structure. It is divided into multiple annular discs from the inside to the outside in the radial direction, which are a grinding fixed ring and multiple grinding stirring rings in sequence. The grinding fixed ring is fixed to the stirring shaft, and the grinding stirring ring adjacent to the grinding fixed ring and the grinding fixed ring, as well as the two adjacent grinding stirring rings, are all connected and fixed by radial bolts, so that the grinding fixed ring and each grinding stirring ring are fixedly combined in sequence to form a complete grinding agitator; each of the grinding stirring rings is divided into at least two parts.

5. The dry stirred mill with controllable material flow according to claim 1, characterized in that The distance between the outer edge of the grinding stirrer and the inner wall of the grinding cylinder is 2 to 10 times the diameter of the grinding medium; a plurality of through holes are evenly arranged on the disk surface of the grinding stirrer along the circumferential direction, and the total through hole area on the disk surface accounts for 0.2 to 0.

6.

6. The dry stirred mill with controllable material flow according to claim 1, characterized in that The grinding cylinder is composed of a cylinder and end covers at both ends, and the end covers are connected to the cylinder by bolts; the cylinder and the end covers are both split structures, each of which can be divided into multiple parts, and the parts are connected and combined by bolts.

7. The dry stirred mill with controllable material flow according to claim 1, characterized in that The ratio of the length to the diameter of the grinding cylinder is 1.5-8, and the grinding cylinder is arranged horizontally; the grinding cylinder is filled with 2-10 mm spherical grinding media, and the grinding media filling rate is 50%-90%.

8. The dry stirred mill with controllable material flow according to claim 1, characterized in that The cooling device includes a cooling shell and heat sinks, wherein an interlayer is formed between the cooling shell and the grinding cylinder body, and a plurality of heat sinks are fixed on the outer wall of the grinding cylinder body in the interlayer; a plurality of heat sinks are also provided on the outer surface of the cooling shell; a cooling medium inlet is provided at the lower part of the cooling shell located at the discharge end side, and a cooling medium outlet is provided at the upper part of the cooling shell located at the feed end side, and the cooling medium flows in the interlayer; the cooling device is a split structure corresponding to the cylinder of the grinding cylinder.

9. The dry stirred mill with controllable material flow according to claim 1, characterized in that The separation device is a hollow hemispherical structure. The small-diameter end of the separation device is detachably fixed to the stirring shaft, and the large-diameter end forms a labyrinth seal with the grinding cylinder. The sieve plate surface of the separation device is provided with circular sieve holes or elongated sieve holes, and the diameter or width of the sieve holes is 0.5 to 0.9 times the diameter of the grinding medium.

10. The dry stirred mill with controllable material flow according to claim 9, characterized in that: An annular sealing plate is provided on the edge of the large diameter end of the sieve plate, and an annular sealing ring is provided on the inner wall of the grinding cylinder. The annular sealing plate and the annular sealing ring are plugged into and matched with each other to form a sealing area.

11. The dry stirred mill with controllable material flow according to claim 1, characterized in that: The feeding port is provided at the upper part of the end cover on one side of the grinding cylinder, and an air-locking feeding device is provided at the feeding port, and the air-locking feeding device allows the material to enter the grinding cylinder at an angle of 45° to 75° with the horizontal direction; the air-locking feeding device comprises a feeder outer shell, a feeder inner shell, an air-locking plate and a weight, the lower part of the feeder inner shell extends into the feeder outer shell, the air-locking plate is placed in the feeder outer shell and below the feeder inner shell, the air-locking plate is fixedly connected to the weight and is installed on the feeder outer shell through a rotating shaft, so that when no material passes through, the air-locking plate is fitted with the bottom end surface of the feeder inner shell under the action of the weight, thereby blocking the feeding channel; When material passes through, the weight of the material separates the air lock plate from the bottom end surface of the feeder inner shell, opening the feeding channel and allowing the material to pass smoothly.

12. The dry stirred mill with controllable material flow according to claim 1, characterized in that: The discharge port is arranged at the bottom of the grinding cylinder body.

13. The dry stirred mill with controllable material flow according to claim 1, characterized in that: The mill air inlet is arranged at the upper part of the grinding cylinder and 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 medium.

14. The dry stirred mill with controllable material flow according to claim 1, characterized in that The mill air outlet is arranged on the upper part of the end cover on the discharge side of the grinding cylinder, the mill air outlet is arranged horizontally, and the downstream of the mill air outlet is connected to the dust collecting equipment.

15. The dry stirred mill with controllable material flow according to claim 1, characterized in that: The shaft drive device is arranged at one end of the feeding side of the grinding cylinder and adopts a permanent magnet direct drive or a motor acceleration and reduction gear drive mode.

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