A method and apparatus for ball milling with variable speed in segments

Abstract

The application discloses a kind of segmented variable-speed ball milling method and ball milling device, belong to ceramic raw material processing equipment technical field.The method includes: ceramic clay and ball stone are sent into low-speed section cylinder to rotate at first rotating speed, and the release height of ball stone is lifted by flow guide structure, and lateral shear grinding is generated;It is transported to the high-speed section cylinder of joint part, and rotates at second rotating speed and third rotating speed in turn, respectively generates positive impact crushing and centrifugal agitation homogenization;Rotating speed switching is automatically executed by controller according to viscosity and current signal;The device is designed with two section cylinders and respective driving motor and flow guide structure structure.The application is designed by flow guide structure, and the release height of ball stone is lifted to higher than the height that can be reached by smooth cylinder wall in low-speed section cylinder, has the advantages that ball stone extrusion acceleration is realized, invalid energy consumption is significantly reduced in mixing stage, grinding efficiency in low-speed section is significantly improved, and comprehensive power saving is realized.

Description

Technical Field

[0001] This invention relates to the field of ceramic raw material processing equipment technology, and in particular to a segmented variable speed ball milling method and ball milling device. Background Technology

[0002] Ball milling is the core raw material processing step in the ceramics industry. Its principle involves adding ceramic clay, water, and grinding media (also known as grinding stones) into a horizontal rotating cylinder. The rotation of the cylinder causes the grinding stones to move relative to the material, utilizing the impact, crushing, and abrasive effects of the grinding stones to mix and grind hard raw materials such as feldspar and quartz with clay materials to the target fineness, ultimately obtaining a ceramic slurry that meets the particle size requirements. Ball mills are the most energy-intensive equipment in the ceramics industry, typically accounting for 30% to 50% of a ceramics company's total electricity consumption. Therefore, improving ball mill efficiency and reducing ball mill energy consumption are major research directions.

[0003] Currently, the ball milling process for ceramic clay mainly employs constant-speed ball milling, meaning the mill cylinder operates at a single, fixed speed throughout the entire milling cycle, from feeding, mixing, fine grinding to discharge. The rotational speed of the mill cylinder determines the movement of the grinding balls within the cylinder, thus influencing the grinding effect. Specifically, at lower speeds, the grinding balls fall along the cylinder wall, resulting in weak impact on the material and low grinding efficiency, suitable only for fine grinding. When the speed is approximately 0.76 times the critical speed, the grinding balls are thrown around, maximizing impact crushing. However, for high-viscosity clays in the mixing stage, this speed leads to motor overload and significant unnecessary power consumption. When the speed exceeds the critical speed, the grinding balls adhere to the cylinder wall due to centrifugal force and rotate with the cylinder without falling, completely losing their impact effect and remaining in an ineffective "centrifugal motion" state. However, constant-speed ball milling, by fixing the rotational speed to a single value, cannot maintain optimal grinding conditions throughout all stages of the process.

[0004] In existing technologies, some solutions employ manual speed adjustment or timed ball milling. The former relies on the operator's experience to manually adjust the speed, lacking standardized control and resulting in poor speed consistency; the latter only controls the grinding time to match the speed, making it difficult to accurately adapt to the optimal grinding state. Other solutions also employ frequency conversion speed regulation or segmented cylinder structures with their own drive systems, but the speed setting still depends on the operator's experience or a fixed timetable, and the energy-saving effect is only within 10%; for example, patents with publication numbers CN203916771U and CN104437768B.

[0005] Analysis of the above technical solutions reveals that their common inherent technical defects are: for high-viscosity mud in the mixing stage, the grinding process can only be carried out by using a low-speed grinding method with low grinding effect, in order to avoid the problems of idling and ineffective energy consumption caused by using medium-speed or high-speed rotation in this stage, thereby achieving a reduction in energy consumption in a lower-efficiency manner.

[0006] Therefore, in view of this inherent technical defect, the present invention designs a segmented variable speed ball milling method and ball milling device. Summary of the Invention

[0007] The purpose of this invention is to provide a segmented variable speed ball milling method and ball milling device, which can solve the problem of low efficiency in existing technologies such as constant speed ball milling, manual speed adjustment, timed ball milling, frequency conversion speed regulation, and segmented cylinder structure, resulting in low grinding effect, and thus reduce energy consumption.

[0008] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution: This invention relates to a segmented variable speed ball mill device, comprising a cylindrical assembly containing two cylindrical sections arranged sequentially along the axial direction: a low-speed section cylindrical section and a medium-to-high-speed section cylindrical section. Each of the two cylindrical sections is equipped with an independent drive motor, and the two cylindrical sections are connected to each other via a connecting component. The front and rear ends of the cylindrical assembly are respectively provided with a feeding section and a discharging section to facilitate material loading and unloading. The design aims to achieve segmented variable speed processing by dividing the cylindrical assembly into different functional sections. The low-speed section cylindrical section and the medium-to-high-speed section cylindrical section correspond to different processing stages, each equipped with an independent drive motor for independent speed control. The two cylindrical sections correspond to a first drive motor and a second drive motor, respectively. This includes wear-resistant liners, which are evenly arranged on the inner wall of the cylinder assembly. Wear-resistant liners are a standard protective structure for ball mill cylinders, protecting them from wear by the balls and materials. Therefore, their surface is relatively smooth, which makes the ceramic clay prone to slipping. Consequently, at low speeds, the inner wall of the cylinder assembly can only lift the balls to a very limited height. The kinetic energy of the balls at this stage is significantly insufficient. The existing equipment design clearly lacks an understanding of the essential differences in the linkage between the "kinetic energy of the balls, the direction of kinetic energy, and their relative motion with the ceramic clay." Therefore, the design includes: the low-speed... The inner wall of the low-speed section cylinder is provided with at least one flow-guiding structure for increasing the release height of the pebbles. This flow-guiding structure, when the low-speed section cylinder rotates at a first rotational speed, releases the pebbles primarily in the tangential direction, ensuring that the lateral shearing effect of the pebbles on the ceramic clay is greater than the direct impact. Segmented speed-changing processing is achieved through two independent cylinders. At low speeds, the flow-guiding structure releases the pebbles primarily in the tangential direction, ensuring that the lateral shearing effect of the pebbles on the ceramic clay is greater than the direct impact. The low-speed section cylinder undertakes the task of the mixing stage, and its key is to ensure that the pebbles obtain sufficient lateral shearing force under low-speed conditions. In existing technologies, at low speeds, the pebbles slide down the smooth cylinder wall at low speeds with insufficient shearing force. Therefore, a flow-guiding structure needs to be provided on the inner wall of the low-speed section cylinder to increase the release height of the pebbles, ensuring that their release is primarily in the tangential direction. Meanwhile, the dual-cylinder design not only facilitates efficiency improvement and reduces ineffective power consumption during the mixing stage through the flow guiding structure, but also avoids interference from the flow guiding structure during the fine grinding and discharge stages. Therefore, the ceramic clay in the fine grinding and discharge stages is transported to the medium-to-high speed section cylinder. The purpose of this segmented design is to avoid interference from the flow guiding structure with subsequent processing steps. At the same time, the second drive motor adopts a variable frequency motor to match the optimal speed of the ceramic clay during the fine grinding and discharge stages.

[0009] Preferably, since wear-resistant liners are a standard protective structure for ball mill cylinders, direct installation on their surface is extremely difficult and unstable, and the gaps between installed wear-resistant liners are small. Therefore, the design includes a flow guiding structure comprising an installation part and a flow guiding assembly. The installation part includes a pre-embedded base and a support frame. The pre-embedded base is fixedly installed between the inner wall of the cylinder assembly and the wear-resistant liner, and the top of the support frame penetrates the gap between two adjacent wear-resistant liners and extends to the inner side of the wear-resistant liner. That is, the installation part needs to fix the pre-embedded base during the installation of the wear-resistant liner, and the support frame can be designed as a flat structure by taking advantage of the small gap between adjacent wear-resistant liners. Alternatively, a relatively large installation gap can be appropriately left at the installation location of the support frame, depending on the actual situation. The advantage of this design is that it eliminates the need for additional holes in the wear-resistant liner, ensuring the integrity and protective effect of the wear-resistant liner; achieving better technical results with fewer disadvantages. The flow guiding assembly includes a torsion plate, one end of which is hinged to the top of the support frame, and a torsion spring is provided at the hinge. The torsion spring is used to force the other end of the torsion plate close to the inner wall of the cylindrical assembly. Limiting blocks are symmetrically provided on two opposing inner sides of the top of the support frame to prevent the other end of the torsion plate from getting closer to the inner wall of the cylindrical assembly. An angle is formed between the tangent direction of the torsion plate and the corresponding position of the inner wall of the cylindrical assembly. The purpose of this design is that the wide opening of the flow guiding assembly tends to be oriented in the direction of rotation, so as to collect and lift the pebbles at the bottom of the inner wall of the cylinder in the low-speed section.

[0010] Preferably, in order to raise the spherical stones to the optimal height, the spherical stones are first collected by the flow guiding assembly; therefore, the design includes: the inner wall of the torsion plate at the corresponding tangent point of the cylindrical assembly forms an inverted "V" shape during the upward rotation phase; the center of gravity of the spherical stones is located between the center of the hinge at one end of the torsion plate and the inner wall of the cylindrical assembly; and a flow guiding gap is formed between the torsion plate and the inner wall of the cylindrical assembly, gradually converging from a wide opening to a narrow opening, so that the spherical stones, after entering from the wide opening end, are accelerated and released from the narrow opening end due to the channel convergence; the flow guiding... During the upward phase, the component forms a guide gap that gradually narrows from a wide opening to a narrow opening. After the spherical stones enter from the wide opening, they are squeezed within the guide gap under the influence of gravity and other forces. Finally, when passing through the end of the guide gap, the upper half of the spherical stones is briefly accelerated due to the brief squeezing force applied by the other end of the torsion plate, and they are released from the narrow opening at a higher tangential velocity. During the sliding process, the gravitational potential energy is converted into kinetic energy. Finally, a higher velocity and greater kinetic energy are achieved, allowing the spherical stones to contact the ceramic clay at the bottom of the low-speed section of the cylinder, thereby enhancing the lateral shearing effect.

[0011] Preferably, in order to lift the spherical stones to the optimal height, the spherical stones are first collected by the flow guiding assembly; therefore, the design includes: the hinge at one end of the torsion plate is installed in the area between the center of gravity of the spherical stone and the inner wall of the cylindrical assembly; during the upward rotation phase of the spherical stone, the weight of the spherical stone overcomes the elastic force of the torsion spring, causing the torsion plate to flip and release around the hinge; during the upward rotation phase of the low-speed section of the cylindrical assembly, the torsion plate, with its constantly changing support surface, exerts a supporting force on the spherical stone. The direction also changes accordingly, and under the influence of the gravity of the ball; the wide opening between the torsion plate and the inner wall of the low-speed section cylinder also gradually increases; finally, the gravity of the ball overcomes the elastic force of the torsion spring, causing the torsion plate to flip around the hinge point, releasing the ball and realizing the directional throwing of the ball, and then converting the gravitational potential energy into kinetic energy during the sliding process; finally, it reaches a relatively high speed and relatively large kinetic energy to contact the ceramic clay at the bottom of the low-speed section cylinder; thereby achieving an enhanced lateral shearing effect.

[0012] Preferably, the axial length of the flow guiding structure is less than 0.95 times the axial length of the low-speed section cylinder, and several flow guiding structures are distributed circumferentially along the low-speed section cylinder; and the central angle between two adjacent flow guiding structures is not less than 90 degrees; the axial length of the flow guiding structure determines the range in which the sphere is lifted axially; setting the axial length to less than 0.95 times the axial length of the cylinder is to reserve a certain space at both ends of the cylinder to avoid interference between the flow guiding structure and the end structure; several flow guiding structures are distributed circumferentially, and the central angle between two adjacent flow guiding structures is not less than 90 degrees; The central angle should not be less than 90 degrees, meaning that a maximum of four guiding structures can be set in the circumference. If there are more than four, the distance between the guiding structures will be too close. After the ball is released from one guiding structure, it will fall into the action area of ​​another guiding structure before it has gained enough space to move. This will cause the ball's movement path to be repeatedly forced to change, making it impossible to form a stable tangential release trajectory. Instead, it will produce a counterproductive effect of mutual interference. By reasonably limiting the axial length and circumferential distribution density of the guiding structures, mutual interference between the guiding structures can be avoided, ensuring that each guiding structure can effectively increase the release height of the ball and achieve tangential release.

[0013] Preferably, the axial length of the guide structure is less than 0.5 times the axial length of the low-speed section cylinder. Several rows of guide structures are evenly distributed along the axial direction of the low-speed section cylinder, with gaps between each row. When the axial length of a single row of guide structures is short, there is axial margin, allowing for the arrangement of multiple rows. The gaps between each row of guide structures prevent mutual interference between adjacent rows, ensuring that the grinding stones can be independently lifted and released at each row. The even distribution of multiple rows of guide structures along the axial direction allows the grinding stones to be lifted and released at different positions along the cylinder's axial direction, thereby improving the grinding uniformity of the material in the axial direction. This short-row, multi-row layout creates multiple release segments in the axial direction, further improving the grinding uniformity of the material in the axial direction.

[0014] A segmented variable speed ball milling method includes the following steps performed sequentially: Step S1: Feed the ceramic clay and grinding balls into the low-speed section of the cylinder assembly; wherein, the grinding balls, as the grinding media, need to be loaded at the same time as the ceramic clay so that grinding can be achieved through the relative motion between the grinding balls and the ceramic clay during subsequent rotation. Step S2: Start the first drive motor corresponding to the low-speed section cylinder, making it rotate at a first speed; during rotation, the release height of the spherical grinding balls is increased by the flow guiding structure set on the inner wall of the low-speed section cylinder, so that the spherical grinding balls grind the ceramic clay in a lateral shearing manner, breaking up and mixing the high-viscosity ceramic clay evenly; at the same time, the viscosity information of the ceramic clay and / or the current information of the first drive motor are collected and transmitted to the controller; wherein, in the initial stage of ball milling, the ceramic clay has high viscosity and poor fluidity. If a high speed is used, the motor will be severely overloaded and energy consumption will be huge. Therefore, the first speed is used to reduce energy consumption; however, at a low speed, the speed at which the spherical grinding balls slide down the smooth cylinder wall is low, and the lateral shearing force is not high. The inability to effectively break down high-viscosity agglomerates inevitably leads to low efficiency and poor grinding effect. Therefore, it is necessary to increase the release height of the grinding balls through a flow guiding structure, so that the grinding balls can still obtain a high tangential velocity under low speed conditions. This allows for grinding dominated by lateral shearing at low speed in the mixing stage, breaking down and uniformly mixing the high-viscosity ceramic clay, thus achieving a high grinding effect at low speed. Although this slightly increases the motor load, it does not cause idling or ineffective work. On the contrary, it reduces the ineffective power consumption at low speed. At the same time, in order to realize the automatic switching of subsequent stages, it is also necessary to collect information reflecting the material status in real time, and collect the material status information in real time for the controller to make judgments. Step S3: When the controller determines that the ceramic clay has entered the fine grinding stage from the mixing stage based on the viscosity information and / or current information, the ceramic clay processed by the low-speed section cylinder is conveyed to the medium-high speed section cylinder through the connecting component, and the second drive motor corresponding to the medium-high speed section cylinder is controlled to rotate at the second speed, so that the pebbles produce a crushing effect on the ceramic clay mainly by positive impact; wherein, when the ceramic clay has a certain fluidity after mixing, the main problem becomes the crushing of hard particles such as feldspar and quartz, which requires the pebbles to generate positive impact in a throwing state; therefore, the material is conveyed to the medium-high speed section cylinder and driven at the second speed, so that the pebbles are in a throwing state, generating a crushing effect mainly by positive impact; that is, in the fine grinding stage, the throwing motion of the pebbles is achieved at a medium speed, generating a crushing effect on hard particles mainly by positive impact; Step S4: When the controller determines that the ceramic slurry has entered the discharge stage from the fine grinding stage based on the viscosity information and / or current information, it controls the second drive motor to rotate at a third speed, so that the ball mills produce a homogenizing effect on the ceramic slurry mainly by lateral shearing and centrifugal agitation; the third speed > the second speed > the first speed; wherein, when the fineness of the ceramic slurry is close to the target value, continuing to grind with positive impact will lead to over-grinding. At this time, it is necessary to use the centrifugal agitation and lateral shearing generated by the high speed to achieve rapid homogenization; that is, in the discharge stage, the high speed is used to achieve rapid homogenization of the slurry, shorten the ball milling time, and avoid over-grinding; Step S5: When the controller determines that the ceramic clay has reached the target fineness based on the viscosity information and / or current information, it stops the ball milling and discharges the material to ensure stable product quality.

[0015] Preferably, the critical speed is a fundamental physical parameter of the ball mill, and defining the speed range as a multiple of the critical speed is a standard expression in the field of ball mill technology. Setting the first speed to 0.50-0.65 times the critical speed ensures that the grinding balls are in a sliding / rolling state rather than a throwing state during the mixing stage, thereby achieving grinding dominated by lateral shear. The grinding effect dominated by lateral shear means that the lateral shear effect of the grinding balls on the ceramic clay is greater than the forward impact effect, thereby reducing ineffective stirring in the high viscosity stage and overload power consumption of the first drive motor; at the same time, the release height of the grinding balls is increased. By reaching a height significantly higher than that of existing equipment in a cascading manner, and utilizing its higher potential energy, and even the kinetic energy of the extrusion during release, the sliding speed of the grinding balls can be significantly increased, thereby applying a highly efficient lateral shearing effect to the ceramic clay. If the grinding balls are thrown, most of their kinetic energy is used for direct impact, which is quickly absorbed and offset. At the same time, the kinetic energy of the thrown grinding balls also acts on the inner wall of the cylinder assembly, causing indirect impact and indirectly reducing the ineffective work done in the throwing manner. This achieves the function of significantly improving the grinding effect and grinding efficiency without changing the rotation speed.

[0016] Preferably, since the ball mill has a high grinding efficiency when the ratio of its operating speed to the critical speed is about 0.76, the second speed is set to 0.75-0.85 times the critical speed to ensure that the balls are in the optimal throwing state; the third speed is set to 0.85-0.95 times the critical speed to ensure that the balls are in a near-centrifugal state, and the centrifugal agitation generated by the high speed is used to achieve rapid homogenization; the range of the second and third speeds is quantified to ensure that the grinding time is shortened with the best grinding efficiency in the fine grinding stage, and the speed is precisely controlled in the discharge stage to avoid excessive collision and idling energy consumption.

[0017] Preferably, in order to achieve automatic speed regulation based on material state, a closed-loop control circuit of "sensing, judging, and executing" needs to be established; the viscosity sensor directly senses the material state, and the current sensor indirectly reflects the motor load and material resistance. The combination of the two can more accurately determine the ball milling stage; therefore, in steps S3 to S4, the controller analyzes and judges the received signals and then sends control commands to the frequency converter to achieve closed-loop automatic speed regulation; no manual intervention is required throughout the process. During the speed switching process from step S3 to step S4, the controller controls the output speed of the second drive motor through the frequency converter and time relay.

[0018] The present invention has the following beneficial effects: 1. This invention enhances the release height of the grinding balls within the low-speed section of the ball mill by incorporating a flow-guiding structure. This structure, located on the inner wall of the low-speed section, raises the release height of the grinding balls above what can be achieved with a smooth inner wall. This allows the grinding balls to be released at a relatively high tangential velocity even at low speeds, resulting in a grinding effect on high-viscosity ceramic clay dominated by lateral shear. This effectively enhances the grinding capacity during the mixing stage without increasing the rotational speed. Currently, in existing constant-speed ball mills, due to the high viscosity and poor fluidity of the ceramic clay, the grinding balls slide slowly under low-speed conditions on a smooth inner wall, resulting in insufficient lateral shear force. Increasing the rotational speed leads to motor overload, current spikes, and significant energy loss as heat. This invention addresses this long-standing technical challenge by reducing ineffective energy consumption in the mixing stage by 20%-30%, eliminating energy waste at the source—one of the most energy-intensive stages in the entire ball milling process—and providing crucial support for comprehensive energy saving in ball milling. It significantly reduces ball mill energy consumption and achieves highly efficient and energy-saving processing.

[0019] 2. The torsion plate in the flow guiding structure designed in this invention forms an angle with the tangential direction of the corresponding position on the inner wall of the cylinder assembly, creating a flow guiding gap that gradually converges from a wide opening to a narrow opening between the torsion plate and the inner wall of the cylinder assembly. After the pebbles enter this flow guiding gap from the wide opening, they are continuously squeezed as the channel gradually converges, and their movement speed continuously increases. Finally, they are released from the narrow opening at a tangential speed higher than the linear velocity of the cylinder wall. This "squeeze, accelerate, release" mechanism enables the pebbles to obtain a higher tangential velocity under low rotational speed conditions, generating a stronger lateral shearing effect on high-viscosity ceramic clay. It significantly enhances the grinding capacity in the mixing stage without increasing the rotational speed, effectively solving the technical problems of low pebble slippage speed and insufficient shear force at low rotational speeds in the prior art. It has the advantages of achieving pebble compression acceleration while significantly reducing ineffective energy consumption in the mixing stage and significantly improving grinding efficiency in the low-speed range.

[0020] 3. The present invention utilizes a preferred circumferential staggered layout in the design of the multi-row short guide structure. By arranging the guide structures in a staggered manner, each row bears the reaction force of the spheres at different times, thus staggering the instantaneous load in time. This effectively reduces the peak load of the first drive motor, resulting in reduced current fluctuations, smoother equipment operation, reduced mechanical impact and wear of the transmission system, and extended equipment lifespan. Furthermore, it avoids the problem that during cylinder rotation, the spheres generate a reaction force on the guide structure, and since the guide structures are aligned axially, the reaction force of each row is concentrated on the same circumferential phase of the cylinder assembly, causing the first drive motor to bear a large instantaneous load peak at that phase, resulting in current surges and mechanical vibrations.

[0021] 4. This invention automatically determines the ball milling stage based on real-time feedback signals from viscosity and / or current sensors, and controls the second drive motor to automatically switch to the optimal speed, so that each stage operates in the optimal grinding state. This avoids prolonged grinding time and ineffective idling caused by improper speed, and has the advantages of significantly shortening the total ball milling time and improving production efficiency.

[0022] 5. This invention achieves standardized control without human intervention throughout the entire process through closed-loop automatic speed regulation, eliminating the uncertainty of manual speed regulation and ensuring that the fineness and fluidity of each batch of ceramic clay remain highly consistent. At the same time, the low-speed operation during the mixing stage avoids motor overload impact under high viscosity conditions, effectively reducing the load on the drive motor and transmission system, and reducing equipment wear and maintenance costs. Attached Figure Description

[0023] Figure 1 This is a schematic flowchart of a segmented variable speed ball milling method provided by the present invention in Embodiment 1; Figure 2 This is a side view of the structure of a segmented speed-changing ball mill device provided by the present invention in Embodiment 2; Figure 3 This is a partial structural schematic diagram of a segmented speed-changing ball mill device provided by the present invention in Embodiment 2; Figure 4 This is a cross-sectional view of a segmented variable speed ball mill device provided by the present invention in Embodiment 3; Figure 5 This is a schematic diagram of the flow guiding structure provided by the present invention in Embodiment 3; Figure 6 for Figure 4 A magnified view of a section at point A in the middle; Figure 7 This is a schematic diagram showing the positional changes of the flow guiding structure provided by the present invention during the compression and release process in Embodiment 3; Figure 8 This is a cross-sectional view of a segmented speed-changing ball mill device provided by the present invention in Embodiment 4; Figure 9 for Figure 8 A magnified view of a section at point B in the middle; Figure 10 This is a schematic diagram showing the positional changes of the flow guiding structure provided by the present invention during the compression and release process in Example 4; Figure 11 This is a cross-sectional view of a segmented speed-changing ball mill device provided by the present invention in Embodiment 5; Figure 12 This is a schematic diagram of the internal layout structure of a segmented speed-changing ball mill device provided by the present invention in Embodiment 5; Figure 13This is a cross-sectional view of a segmented speed-changing ball mill device provided by the present invention in Embodiment 5; Figure 14 This is a schematic diagram of the internal layout structure of a segmented speed-changing ball mill device provided by the present invention in Embodiment 5.

[0024] Explanation of reference numerals in the attached figures: 1. Cylinder assembly; 101. Low-speed section cylinder; 102. Medium- and high-speed section cylinder; 103. Feeding section; 104. Discharge section; 2. Drive motor; 201. First drive motor; 202. Second drive motor; 3. Connecting component; 4. Stone ball; 5. Flow guiding structure; 501. Mounting part; 5011. Embedded base; 5012. Support frame; 5013. Limiting block; 502. Flow guiding assembly; 5021. Torsion plate; 6. Wear-resistant liner. Detailed Implementation

[0025] The specific embodiments of the present invention will be described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0026] Example 1 This embodiment provides a segmented variable speed ball milling method, such as... Figure 1 As shown, the steps are performed sequentially: Step S1, Feeding Step: The ceramic clay and grinding stones 4 are fed into the low-speed section cylinder 101 of the cylinder assembly 1. In this step, the ceramic clay is a mixture of a semi-solid blocky mixture with a water content below the plastic limit and hard particles such as feldspar and quartz, with a water content typically below 15%-25%. The grinding stones 4, as grinding media, are loaded into the low-speed section cylinder 101 together with the ceramic clay. The diameter of the grinding stones 4 is selected according to process requirements, typically 40mm-120mm.

[0027] Step S2, Mixing Step: Start the first drive motor 201 corresponding to the low-speed section cylinder 101, making it rotate at a first speed. During rotation, the release height of the spherical stones 4 is increased by the flow guiding structure 5 set on the inner wall of the low-speed section cylinder 101, so that the spherical stones 4 grind the ceramic clay in a lateral shearing manner, breaking down and mixing the high-viscosity ceramic clay evenly. At the same time, the viscosity information of the ceramic clay and / or the current information of the first drive motor 201 are collected and transmitted to the controller. In this step, the first speed is a low speed, preferably 0.50-0.65 times the critical speed. At this speed, the spherical stones 4 are in a sliding / rolling motion state in the cylinder. Since the inner wall of the low-speed section cylinder 101 is provided with the flow guiding structure 5, the spherical stones 4 are blocked and lifted by the flow guiding structure 5, and their release height is higher than the height that the smooth cylinder wall can reach. The spherical stones 4 are released mainly in the tangential direction, obtaining a high tangential velocity. The grinding stone 4 grinds the ceramic clay primarily using lateral shearing, breaking down and uniformly mixing the high-viscosity ceramic clay. Simultaneously, a viscosity sensor collects the viscosity signal of the ceramic clay in real time, and a current sensor collects the current signal of the first drive motor 201 in real time; both are transmitted to the controller.

[0028] During the mixing stage, the ceramic clay is characterized by coarse texture, high viscosity, and poor fluidity. In this stage, the lateral shearing effect of the spherical stones 4 on the ceramic clay is greater than the forward impact, thereby reducing ineffective stirring and overload power consumption of the first drive motor 201 during the high-viscosity stage.

[0029] Step S3, Fine Grinding Step: When the controller determines that the ceramic clay has entered the fine grinding stage from the mixing stage based on viscosity and / or current information, the ceramic clay processed by the low-speed section cylinder 101 is conveyed to the medium-high speed section cylinder 102 through the connecting component 3. The second drive motor 202 corresponding to the medium-high speed section cylinder 102 is controlled to rotate at a second speed, so that the grinding balls 4 produce a crushing effect on the ceramic clay mainly by positive impact. In this step, the controller determines the state change of the ceramic clay based on the received viscosity signal and / or current signal. When the viscosity drops to a preset threshold, the controller determines that the ceramic clay has entered the fine grinding stage from the mixing stage. At this time, the ceramic clay processed by the low-speed section cylinder 101 is conveyed to the medium-high speed section cylinder 102 through the hollow channel of the connecting component 3. The second speed is a medium speed, preferably 0.75-0.85 times the critical speed. At this rotational speed, the ball stone 4 is in a throwing motion state inside the cylinder, which produces a crushing effect on the ceramic clay mainly by positive impact, crushing hard particles such as feldspar and quartz to the target fineness.

[0030] The ceramic clay in the fine grinding stage is characterized by finer particles and moderate viscosity. During this stage, the optimal grinding efficiency is maintained by rotating at the second rotation speed to shorten grinding time.

[0031] Step S4, Homogenization Step: When the controller determines that the ceramic slurry has entered the discharge stage from the fine grinding stage based on viscosity and / or current information, it controls the second drive motor 202 to rotate at a third speed, causing the ball mill 4 to produce a homogenization effect on the ceramic slurry dominated by lateral shearing and centrifugal agitation; the third speed > the second speed > the first speed. In this step, when the viscosity further decreases to the second preset threshold, the controller determines that the ceramic slurry has entered the discharge stage from the fine grinding stage. At this time, the controller controls the second drive motor 202 to rotate at a third speed. The third speed is a high speed, preferably 0.85-0.95 times the critical speed. At this speed, the ball mill 4 is in a near-centrifugal state inside the cylinder, producing a homogenization effect on the ceramic slurry dominated by lateral shearing and centrifugal agitation, achieving rapid homogenization of the slurry and shortening the ball milling time.

[0032] During the discharge stage, the ceramic clay is characterized by fine texture, low viscosity, and good fluidity. At this stage, precise speed control is employed when rotating at the third rotation speed to avoid excessive collisions and energy consumption from idling.

[0033] Step S5, Discharge Step: When the controller determines that the ceramic clay has reached the target fineness based on viscosity and / or current information, it stops the ball mill and discharges the material. In this step, the target fineness is preferably 0.2%-1.2% residue on a 325-mesh sieve. When the controller determines that the ceramic clay has reached the target fineness, it stops the ball mill and discharges the material.

[0034] The speed switching control method is as follows: During the speed switching process from steps S2 to S4, signals are collected by a viscosity sensor and / or a current sensor and transmitted to the controller. The controller sends control commands to the frequency converter based on the received signals to achieve closed-loop automatic speed regulation. During the speed switching process from steps S3 to S4, the controller controls the output speed of the second drive motor 202 through the frequency converter and a time relay.

[0035] As an alternative to this embodiment, speed switching can also be achieved by pre-setting multiple speed curves through a programmable logic controller (PLC) and automatically switching speeds according to viscosity signals, without any manual intervention. The PLC can also control speed switching in conjunction with time and / or current signals.

[0036] As an alternative to this embodiment, the three stages can be expanded to four or five more refined speed curves, and a special program can be customized according to the type of ceramic clay such as kaolin, feldspar, and quartz.

[0037] As an alternative to this embodiment, this method can also be applied to various other equipment such as horizontal ball mills, vertical ball mills, and high-speed ball mills.

[0038] Example 2 This embodiment provides a segmented variable speed ball mill device, such as... Figures 2 to 3 As shown, it includes the following; Cylinder assembly 1: Cylinder assembly 1 contains two cylinders arranged sequentially along the axial direction, namely a low-speed section cylinder 101 and a medium-high speed section cylinder 102; the low-speed section cylinder 101 is used to perform low-speed lateral shear grinding in the mixing stage, and the medium-high speed section cylinder 102 is used to perform medium-speed forward impact crushing in the fine grinding stage and high-speed centrifugal homogenization in the discharge stage. Drive motor 2: Each of the two cylinders is equipped with an independent drive motor 2; the low-speed section cylinder 101 corresponds to the first drive motor 201, and the medium- and high-speed section cylinder 102 corresponds to the second drive motor 202; the two drive motors 2 are independently controlled, so that the two cylinders can rotate at different speeds; the second drive motor 202 is a variable frequency motor; the first drive motor 201 is either a fixed frequency motor or a variable frequency motor, depending on the rated speed requirements of different materials and the cost of the equipment. Connecting component 3: The two cylinders are connected to each other through the connecting component 3; the connecting component 3 has a hollow channel for material to pass through, and the two cylinders can rotate independently around the connecting component 3; the connecting component 3 is fixed to the mounting surface of the ball mill by a fixed frame. Feeding section 103 and discharging section 104: The front end and the rear end of the cylinder assembly 1 are respectively provided with a feeding section 103 and a discharging section 104; the feeding section 103 is located at the front end of the low-speed section cylinder 101 and is used to feed ceramic clay and ball stones 4 into the cylinder; the discharging section 104 is located at the rear end of the medium-speed section cylinder 102 and is used to discharge the ceramic slurry after ball milling. Flow guiding structure 5: The inner wall of the low-speed section cylinder 101 is provided with a flow guiding structure 5 for raising the release height of the ball stone 4; the flow guiding structure 5 is used to release the ball stone 4 in the tangential direction when the low-speed section cylinder 101 rotates at the first speed, so that the lateral shearing effect of the ball stone 4 on the ceramic clay is greater than the positive impact effect. Wear-resistant liner 6: Wear-resistant liner 6 is evenly arranged on the inner wall of the cylinder assembly 1; the wear-resistant liner 6 is an arc-shaped plate structure, evenly arranged along the circumference and axial direction of the inner wall of the cylinder assembly 1, with the required gap only between two adjacent wear-resistant liners 6 where the flow guiding structure 5 needs to be installed, and the other positions are the gaps for normal installation; the material of the wear-resistant liner 6 is preferably high-alumina ceramic or high-manganese steel.

[0039] The number of flow guiding structures 5 can be one or more; when multiple flow guiding structures 5 are set, they are evenly distributed along the circumference of the low-speed section cylinder 101.

[0040] The core design of this embodiment is as follows: ceramic clay and ball milling stones 4 enter the low-speed section cylinder 101 from the feed section 103; the first drive motor 201 drives the low-speed section cylinder 101 to rotate at a first speed, i.e., low speed state; during rotation, the guide structure 5 raises the release height of the ball milling stones 4, so that the ball milling stones 4 are released mainly in the tangential direction, producing a grinding effect on the ceramic clay mainly in the lateral shearing direction; the ceramic clay processed by the low-speed section cylinder 101 enters the medium-high speed section cylinder 102 through the hollow channel of the connecting component 3; the second drive motor 202 drives the medium-high speed section cylinder 102 to rotate at the second speed and the third speed in sequence according to the controller's instructions, i.e., medium speed and high speed respectively, to achieve a crushing effect mainly in the positive impact and a homogenization effect mainly in the lateral shearing and centrifugal stirring direction respectively; finally, the ceramic slurry after ball milling is discharged from the discharge section 104.

[0041] Example 3 A more preferred technical solution based on Embodiment 2 is a specific implementation of the flow guiding structure 5, such as... Figures 4 to 7 As shown, the flow guiding structure 5 includes an installation part 501 and a flow guiding assembly 502; the installation part 501 includes a pre-embedded base 5011 and a support frame 5012; the pre-embedded base 5011 is fixedly installed between the inner wall of the cylinder assembly 1 and the wear-resistant liner 6. Specifically, the bottom surface of the pre-embedded base 5011 is attached to the inner wall of the cylinder assembly 1, and the wear-resistant liner 6 covers the pre-embedded base 5011; the top of the support frame 5012 passes through the gap between two adjacent wear-resistant liners 6 and extends to the inner side of the wear-resistant liner 6; the support frame 5012 has a plate-like structure and extends radially along the cylinder assembly 1; that is, the installation part 501 needs to be installed before the installation process of the wear-resistant liner 6. Among them, such as Figure 5 and Figure 6 As shown, the flow guiding assembly 502 includes a torsion plate 5021; one end of the torsion plate 5021 is hinged to the top of the support frame 5012, and a torsion spring is provided at the hinge; the torsion spring is used to force the other end of the torsion plate 5021 to approach the inner wall of the cylinder assembly 1; two opposite inner sides of the top of the support frame 5012 are symmetrically provided with limiting blocks 5013 to prevent the other end of the torsion plate 5021 from approaching the inner wall of the cylinder assembly 1 further, that is, to maintain the wide opening of the flow guiding assembly 502 in the direction of rotation, and to avoid the narrow opening in the direction of rotation; the limiting block 5013 protrudes inward from the inner side of the support frame 5012, and when the torsion plate 5021 rotates to a predetermined angle towards the inner wall of the cylinder assembly 1 under the action of the torsion spring, the side of the torsion plate 5021 abuts against the limiting block 5013, preventing it from continuing to rotate.

[0042] Among them, such as Figure 7As shown, the design of the included angle and the flow guide gap is as follows: Under the restriction of the limiting block 5013, the torsion plate 5021 and the tangential direction of the corresponding position of the inner wall of the cylinder assembly 1 form an included angle; this included angle makes the flow guide gap between the torsion plate 5021 and the inner wall of the cylinder assembly 1 gradually converge from the wide opening to the narrow opening.

[0043] Among them, such as Figure 7 As shown, this is a specific implementation of the "V"-shaped structure formed between the torsion plate 5021 and the inner wall of the cylinder assembly 1, as follows: Figure 5 As shown. The "eight"-shaped structure: During the upward rotation phase, the inner wall of the torsion plate 5021 at the corresponding tangent point to the cylinder assembly 1 forms an inverted "eight"-shaped structure. Specifically, the torsion plate 5021 extends obliquely from the hinge point towards the rear in the direction of cylinder rotation, forming a channel between itself and the inner wall of the cylinder assembly 1 that gradually narrows from a wide opening to a narrow opening, its shape resembling an inverted "eight".

[0044] Among them, such as Figure 7 As shown, the center of gravity of the ball stone 4 is located between the center of the hinge at one end of the torsion plate 5021 and the inner wall of the cylinder assembly 1. This positional relationship ensures that the ball stone 4 can be correctly guided and accelerated when entering the guide gap.

[0045] Among them, such as Figure 7 As shown, the guiding gap and the principle of accelerated release are as follows: A guiding gap is formed between the torsion plate 5021 and the inner wall of the cylinder assembly 1, gradually converging from the wide opening to the narrow opening. After the ball stone 4 enters from the wide opening end, as the channel gradually converges, the ball stone 4 is continuously squeezed and finally released from the narrow opening end at a tangential velocity higher than the linear velocity of the cylinder wall.

[0046] The core design of this embodiment is as follows: During the upward phase of the ball mill's rotation, the ball 4 moves from the bottom to the top along with the cylinder wall. When the ball 4 reaches the guide structure 5, it enters the guide gap between the torsion plate 5021 and the inner wall of the cylinder assembly 1 from the wide end. As the channel gradually converges from the wide end to the narrow end, the ball 4 is continuously squeezed during its movement. When the force change of the cylinder assembly 1 during rotation causes the ball 4 to reach the narrow end, the other end of the torsion plate 5021 still applies a brief squeezing force to the upper half of the ball 4, causing it to be briefly accelerated upon release. It is released from the narrow end at a higher tangential velocity, and then the gravitational potential energy is converted into kinetic energy during the sliding process. Finally, it reaches a higher speed and greater kinetic energy to contact the ceramic clay at the bottom of the cylinder 101 in the low-speed section, thereby achieving a strong lateral shearing effect on the ceramic clay.

[0047] The advantages of this installation method are: the pre-embedded base 5011 is fixed between the inner wall of the cylinder assembly 1 and the wear-resistant liner 6, and the top of the support frame 5012 extends through the gap between two adjacent wear-resistant liners 6 to the inner side of the wear-resistant liner 6. This installation method makes full use of the gap between the wear-resistant liners 6 as the installation channel of the flow guiding structure 5, without the need for additional holes in the wear-resistant liner 6, thus ensuring the integrity and protective effect of the wear-resistant liner 6.

[0048] As an alternative to this embodiment, the flow guiding structure 5 can be a lifting bar that extends axially along the inner wall of the low-speed section cylinder 101, with a helix angle of 15°-30°.

[0049] As an alternative to this embodiment, the flow guiding structure 5 can be the corner of a regular polygon with 6-8 sides in the cross-section of the inner cavity of the low-speed section cylinder 101.

[0050] Example 4 A more preferred technical solution is proposed based on Embodiment 2, namely, the specific implementation of the method for flipping the torsion plate 5021 to release the ball stone 4, as follows: Figures 8 to 10 As shown; the hinge is located at one end of the torsion plate 5021 in the area between the center of gravity of the ball stone 4 and the inner wall of the cylinder assembly 1. Specifically, the hinge is set close to the inner wall of the cylinder assembly 1, while the center of gravity of the ball stone 4 is located outside the hinge, that is, on the side away from the cylinder wall.

[0051] Among them, such as Figure 10 As shown, the flip-release principle is as follows: During the upward phase of rotation, the ball 4 falls from above onto the free end of the other end of the torsion plate 5021. The gravity of the ball 4 and the impact force generated by its fall produce a torque at the hinge. When this torque is greater than the elastic torque of the torsion spring, the torsion plate 5021 flips about the hinge towards the axis of the cylinder assembly 1. After flipping, the ball 4 is released from the torsion plate 5021 and flies out tangentially. After release, the torsion spring returns the torsion plate 5021 to its initial position, ready to receive the impact of the next ball 4.

[0052] Working principle: During the rotation of the ball mill, the ball 4 is carried to a certain height and falls along a trajectory, landing on the free end of the torsion plate 5021. The gravity and impact force of the ball 4 generate an instantaneous impact torque at the hinge, overcoming the elastic torque of the torsion spring and causing the torsion plate 5021 to flip. After being released, the ball 4 continues to move tangentially, exerting a lateral shearing effect on the ceramic clay. The torsion spring then resets the torsion plate 5021.

[0053] Example 5 A more preferred technical solution based on Embodiment 2 is as follows: Figures 11 to 14 As shown, this embodiment provides two layout options for the flow guiding structure 5: One of the layout methods is as follows: Figures 11 to 12 As shown, the single-row long guide structure 5 has an axial length that is less than 0.95 times the axial length of the low-speed section cylinder 101. Several guide structures 5 are distributed circumferentially along the low-speed section cylinder 101, and the central angle between two adjacent guide structures 5 is not less than 90 degrees.

[0054] Specifically, such as Figures 11 to 12 As shown, the axial length of the guide structure 5 determines the range in which the ball stone 4 is lifted axially. Setting the axial length to be less than 0.95 times the axial length of the cylinder is to reserve a certain space at both ends of the cylinder, avoiding interference between the guide structure 5 and the end structure. Several guide structures 5 are distributed circumferentially, with the central angle between two adjacent guide structures 5 not less than 90 degrees, meaning a maximum of four guide structures 5 can be set circumferentially. If there are more than four, the distance between the guide structures 5 will be too close, and the ball stone 4, after being released from one guide structure 5, will fall into the action area of ​​another guide structure 5 before gaining sufficient space for movement. This causes the movement path of the ball stone 4 to be repeatedly forced to change, making it impossible to form a stable tangential release trajectory, and instead producing a counter-effect of mutual interference. Therefore, the limitation of a central angle of not less than 90 degrees ensures that there is sufficient spacing between the guide structures 5 to avoid mutual interference.

[0055] The second layout method is as follows: Figures 13 to 14 As shown, the multi-row short guide structure has an axial length that is less than 0.5 times the axial length of the low-speed section cylinder 101. Several rows of guide structures 5 are evenly distributed along the axial direction of the low-speed section cylinder 101, and gaps are provided between each row of guide structures 5.

[0056] Specifically, such as Figures 13 to 14 As shown, when the axial length of a single row of guide structures 5 is shorter than 0.5 times the axial length of the cylinder, there is axial margin, allowing for the arrangement of multiple rows of guide structures 5. Gaps are provided between each row of guide structures 5 to avoid mutual interference between adjacent rows, ensuring that the grinding stones 4 can be independently lifted and released at each row of guide structures 5. The multiple rows of guide structures 5 are evenly distributed along the axial direction, enabling the grinding stones 4 to be lifted and released at different positions along the cylinder's axial direction, thereby improving the uniformity of material grinding in the axial direction.

[0057] Preferably, such as Figure 14As shown, layout method two can also be designed with a staggered distribution: several rows of guide structures 5 are staggered in the circumferential direction of the low-speed section cylinder 101. Because the distribution of the spherical stones 4 on the inner wall of the cylinder assembly 1 is uneven and there is a large accumulation of spherical stones 4 at the bottom of the cylinder, if the rows of guide structures 5 are aligned axially, the reaction force of the spherical stones 4 on each row of guide structures 5 will be concentrated on the same circumferential phase of the cylinder assembly 1, causing the first drive motor 201 to bear a large instantaneous load peak at that phase. However, by staggering the rows of guide structures 5 in the circumferential direction, each row of guide structures 5 can bear the reaction force of the spherical stones 4 at different times, thus staggering the instantaneous load in time, thereby reducing the peak load of the first drive motor 201, reducing current fluctuations, making the first drive motor 201 run more smoothly, and reducing the mechanical impact of the transmission system.

[0058] The segmented variable speed ball mill device and method provided by this invention can be widely applied to the ball milling of various materials such as ceramic clay, glaze, and chemical slurry. This invention increases the release height of the grinding balls 4 during the mixing stage through the flow guiding structure 5 on the inner wall of the low-speed section cylinder 101. This allows the grinding balls 4 to maintain a high tangential velocity at low speeds while still producing a grinding effect on high-viscosity ceramic clay dominated by lateral shearing. Thus, low-power, high-efficiency grinding can be achieved during the mixing stage, effectively reducing ineffective energy consumption in this stage by approximately 20%-30%. Combined with the medium-speed crushing dominated by positive impact in the fine grinding stage and the high-speed homogenization dominated by centrifugal agitation in the discharge stage, the speeds at each stage are precisely matched to the material state, resulting in comprehensive energy savings of 15%-35%. Simultaneously, it significantly improves grinding efficiency and stabilizes product quality, demonstrating good industrial practical value and promising application prospects.

[0059] The above-disclosed embodiments are merely a few specific examples of the present invention. However, the embodiments of the present invention are not limited thereto, and any variations that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A segmented variable speed ball mill device, comprising a cylinder assembly (1), the cylinder assembly (1) containing two cylinders arranged sequentially along the axial direction, namely a low-speed section cylinder (101) and a medium-high speed section cylinder (102); each of the two cylinders is equipped with an independent drive motor (2), and the two cylinders are connected to each other by a connecting component (3); the front end and rear end of the cylinder assembly (1) are respectively provided with a feeding part (103) and a discharging part (104); characterized in that, The inner wall of the low-speed section cylinder (101) is provided with at least one flow guide structure (5) for raising the release height of the ball (4). The flow guide structure (5) is used to release the ball (4) in the tangential direction when the low-speed section cylinder (101) rotates at a first speed, so that the lateral shearing effect of the ball (4) on the ceramic clay is greater than the positive impact effect.

2. The segmented speed-changing ball mill device as described in claim 1, further comprising wear-resistant liners (6), wherein the inner wall of the cylinder assembly (1) is uniformly provided with wear-resistant liners (6); characterized in that, The flow guiding structure (5) includes an installation part (501) and a flow guiding assembly (502); the installation part (501) includes a pre-embedded base (5011) and a support frame (5012); the pre-embedded base (5011) is fixedly installed between the inner wall of the cylinder assembly (1) and the wear-resistant liner (6), and the top of the support frame (5012) passes through the gap between two adjacent wear-resistant liners (6) and extends to the inner side of the wear-resistant liner (6); The flow guiding assembly (502) includes a torsion plate (5021), one end of which is hinged to the top of the support frame (5012), and a torsion spring is provided at the hinge. The torsion spring is used to force the other end of the torsion plate (5021) to approach the inner wall of the cylinder assembly (1). Limiting blocks (5013) are symmetrically arranged on the two inner sides opposite to the top of the support frame (5012) to prevent the other end of the torsion plate (5021) from getting closer to the inner wall of the cylinder assembly (1); an angle is formed between the torsion plate (5021) and the tangential direction at the corresponding position of the inner wall of the cylinder assembly (1).

3. The segmented speed-changing ball mill device as described in claim 2, characterized in that, The inner wall of the torsion plate (5021) at the corresponding tangent point of the cylinder assembly (1) forms an inverted "eight" shape during the upward rotation phase; the center of gravity of the ball (4) is located between the center of the hinge at one end of the torsion plate (5021) and the inner wall of the cylinder assembly (1); and a flow guide gap is formed between the torsion plate (5021) and the inner wall of the cylinder assembly (1) that gradually converges from the wide opening to the narrow opening, and the ball (4) is accelerated and released from the narrow opening after entering from the wide opening end due to the convergence of the channel.

4. The segmented speed-changing ball mill device as described in claim 2, characterized in that, The hinge at one end of the torsion plate (5021) is installed in the area between the center of gravity of the ball (4) and the inner wall of the cylinder assembly (1); when the ball (4) is rotating upward, the gravity of the ball (4) overcomes the elastic force of the torsion spring, causing the torsion plate (5021) to flip and release around the hinge.

5. A segmented speed-changing ball mill device as described in claim 1, characterized in that, The axial length of the flow guiding structure (5) is less than 0.95 times the axial length of the low-speed section cylinder (101), and several flow guiding structures (5) are distributed circumferentially along the low-speed section cylinder (101); and the central angle between two adjacent flow guiding structures (5) is not less than 90 degrees.

6. The segmented speed-changing ball mill device as described in claim 1, characterized in that, The axial length of the flow guiding structure (5) is less than 0.5 times the axial length of the low-speed section cylinder (101). Several rows of flow guiding structures (5) are evenly distributed along the axial direction of the low-speed section cylinder (101), and there is a gap between each row of flow guiding structures (5).

7. A segmented variable speed ball milling method as described in any one of claims 1-6, characterized in that, This includes the following steps performed sequentially: Step S1: Feed the ceramic clay and pebbles (4) into the low-speed section of the cylinder (101) of the cylinder assembly (1); Step S2: Start the first drive motor (201) corresponding to the low-speed section cylinder (101) and make it rotate at the first speed; during the rotation, the release height of the ball stone (4) is increased by the flow guiding structure (5) set on the inner wall of the low-speed section cylinder (101), so that the ball stone (4) grinds the ceramic clay in a lateral shearing manner, and disperses and mixes the high-viscosity ceramic clay evenly; at the same time, collect the viscosity information of the ceramic clay and / or the current information of the first drive motor (201) and transmit it to the controller; Step S3: When the controller determines that the ceramic clay has entered the fine grinding stage from the mixing stage based on the viscosity information and / or current information, the ceramic clay processed by the low-speed section cylinder (101) is transported to the medium-high speed section cylinder (102) through the connecting component (3), and the second drive motor (202) corresponding to the medium-high speed section cylinder (102) is controlled to rotate at the second speed, so that the pebbles (4) produce a crushing effect on the ceramic clay dominated by positive impact; Step S4: When the controller determines that the ceramic clay has entered the discharge stage from the fine grinding stage based on the viscosity information and / or current information, it controls the second drive motor (202) to rotate at the third speed, so that the pebbles (4) produce a homogenization effect on the ceramic clay mainly by lateral shearing and centrifugal stirring; the third speed > the second speed > the first speed; Step S5: When the controller determines that the ceramic clay has reached the target fineness based on the viscosity information and / or current information, it stops the ball mill and discharges the material.

8. The segmented variable speed ball milling method as described in claim 7, characterized in that, In step S2, the first rotational speed is 0.50-0.65 times the critical rotational speed; the grinding action dominated by lateral shear means that the lateral shearing action of the ball (4) on the ceramic clay is greater than the positive impact action.

9. The segmented variable speed ball milling method as described in claim 7, characterized in that, In step S4, the second rotational speed is 0.75-0.85 times the critical rotational speed, and the third rotational speed is 0.85-0.95 times the critical rotational speed.

10. The segmented variable speed ball milling method as described in claim 7, characterized in that, In steps S3 to S4, the controller analyzes and judges the received signal and then sends a control command to the frequency converter to achieve closed-loop automatic speed regulation. During the speed switching process from step S3 to step S4, the controller controls the output speed of the second drive motor (202) through the frequency converter and time relay.

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