A coating grinding process for reducing the start-up resistance of a vertical grinder

Abstract

The application discloses a paint grinding process for reducing the starting resistance of a vertical grinder and relates to the field of paint grinding, and aims to solve the problem of large starting resistance of a vertical grinder, which causes abnormal increase of motor load, threatens safe operation of equipment, and increases energy consumption and maintenance cost, and comprises a grinding cylinder, a lifting driving shaft is arranged in the grinding cylinder, an upper grinding assembly and a lower grinding assembly are arranged on the driving shaft, the upper grinding assembly is located above the lower grinding assembly and is used for rough crushing of materials, the lower grinding assembly is used for fine grinding of materials, and an overload protection mechanism is arranged between the lower grinding assembly and the upper grinding assembly, and the process has the advantages of significantly reducing the starting resistance, avoiding motor blockage and tripping, and improving the operation safety of equipment and production efficiency.

Description

Technical Field

[0001] This invention relates to the field of coating grinding technology, and in particular to a coating grinding process for reducing the starting resistance of a vertical grinding mill. Background Technology

[0002] Vertical grinding mills, as a core type of wet grinding and dispersing equipment, play an irreplaceable role in the fine processing of materials in industries such as coatings, inks, dyes, and pesticides. Their basic working principle relies on the driving force of a rotating grinding shaft inside the grinding cylinder. This shaft drives the dispersing or grinding disc to rotate at high speed, causing continuous collisions, shearing, and friction between the grinding media (such as zirconium beads or glass beads) and the material to be processed. This results in the gradual crushing and uniform dispersion of the material particles, ultimately achieving the target fineness. These machines are widely used in industrial production due to their simple structural design, flexible color-changing operation, convenient cleaning and maintenance, and easy overall operation. However, the traditional "full-volume feeding, direct start" operation mode commonly used in coating grinding processes has revealed significant drawbacks in actual operation. Specifically, operators are accustomed to feeding all the material to be ground into the grinding cylinder at once, then adding a fixed amount of grinding media, and immediately starting the motor to drive the grinding shaft to rotate for overall grinding. This operating method faces severe challenges during the startup phase: due to the naturally uneven particle size distribution of the material, containing a large number of unbroken large particle agglomerates and some dispersed fine particles, during equipment shutdown or standby, solid particles and grinding media inevitably settle and accumulate at the bottom of the grinding cylinder under gravity, forming a dense and hard sediment layer. At this time, the grinding components at the lower end of the grinding shaft are completely buried in this sediment layer. At startup, it is necessary to overcome the huge static friction between the material and the grinding media and the compaction resistance of the sediment layer, resulting in a startup torque that far exceeds the normal torque requirements of the equipment during normal operation. Especially for high-viscosity coating materials, under low-temperature environments or long-term static conditions, the "braking" effect of the sediment layer is significantly amplified, manifesting as difficulty in starting the motor, frequent stalling or tripping, and in severe cases, even motor burnout due to prolonged forced starting, causing equipment damage and production interruption. In addition, the dense structure of the sediment layer further amplifies the startup resistance problem, causing abnormally high motor load, which not only threatens the safe operation of the equipment but also increases energy consumption and maintenance costs. Existing technologies have failed to effectively address this startup resistance problem, resulting in low production efficiency and shortened equipment lifespan, necessitating innovation and improvement at the process level. Summary of the Invention

[0003] In view of the above situation and to overcome the defects of the prior art, the present invention provides a coating grinding process to reduce the starting resistance of vertical grinding machines. This design effectively solves the problem that the starting resistance of vertical grinding machines is too high, which causes abnormally high motor load, not only threatening the safe operation of the equipment, but also increasing energy consumption and maintenance costs.

[0004] To achieve the above objectives, the present invention provides the following technical solution: The present invention includes a grinding cylinder, wherein a liftable drive shaft is provided inside the grinding cylinder, and an upper grinding component and a lower grinding component are provided on the drive shaft. The upper grinding component is located above the lower grinding component and is used for coarse crushing of the material, and the lower grinding component is used for fine grinding of the material. An overload protection mechanism is provided between the lower grinding component and the upper grinding component. During startup, the drive shaft is raised to a position where the lower grinding component is disengaged from or lightly contacts the material deposited at the bottom of the grinding cylinder, and the drive shaft is driven to rotate. The upper grinding component first performs coarse crushing and agitation on the material to reduce startup resistance. Once the drive shaft speed stabilizes, control the drive shaft to descend, causing the lower grinding assembly to begin working and perform fine grinding. During the grinding process, when the resistance experienced by the lower grinding component exceeds the set value of the overload protection mechanism, the overload protection mechanism disconnects or causes slippage between the lower grinding component and the upper grinding component, causing the lower grinding component to stop rotating while only the upper grinding component continues to rotate; when the resistance decreases below the set value, the overload protection mechanism restores the power transmission between the lower grinding component and the upper grinding component, allowing fine grinding to continue.

[0005] Preferably, the upper grinding assembly includes a sleeve, which is fixedly connected to the drive shaft. A blade is fixedly connected to the outside of the sleeve, and a grinding column is provided below the blade. The grinding column is fixedly connected to the sleeve.

[0006] Preferably, the sleeve is fixedly connected to a limiting rod, the blades are in multiple sets, and the multiple sets of blades are equidistantly arranged on the limiting rod. The grinding column is an inverted L-shaped structure, and the grinding column is located on the periphery of the lower grinding assembly.

[0007] Preferably, the lower grinding assembly includes a grinding disc, a cone and a ball are fixedly connected below the grinding disc, a groove is opened on the side of the grinding disc, a filter plate is rotatably connected below the grinding disc, and the filter plate is fixedly connected to the grinding cylinder.

[0008] Preferably, the overload protection mechanism includes a bushing, which is fixedly connected to the drive shaft. The bushing has a cavity inside. A first connecting shaft is fixedly connected to the bushing. A connecting sleeve is fitted below the first connecting shaft. A second connecting shaft is fitted below the connecting sleeve. A first limiting pin is fixedly connected to the first connecting shaft. A limiting groove that mates with the first connecting pin is provided above the connecting sleeve. A second limiting pin is fixedly connected to the second connecting shaft. A guide groove for the second limiting pin to slide is provided on the connecting sleeve. The second connecting shaft is fixedly connected to the lower grinding assembly. A baffle is fixedly connected to the second connecting shaft. A spring that applies upward force to the connecting sleeve is provided between the baffle and the connecting sleeve.

[0009] Preferably, there are four of each of the first and second limiting pins, and the limiting groove has an arc-shaped ramp on its side.

[0010] Preferably, the drive shaft is fixedly connected to a housing, a lifting rod is connected to the side of the housing, a base is fixedly connected below the lifting rod, and the grinding cylinder is located on the side of the lifting rod.

[0011] Preferably, one side of the grinding cylinder is hinged to the base, and a telescopic rod is installed between the other side of the grinding cylinder and the base.

[0012] Preferably, the grinding cylinder is provided with clamping blocks on both sides, and the clamping blocks are threadedly connected to the base.

[0013] Preferably, a fixing buckle is fixedly connected to the lifting rod, and two sets of symmetrically distributed cover plates are rotatably connected to the fixing buckle. A through hole that cooperates with the drive shaft is provided between the two cover plates.

[0014] Compared with the prior art, the outstanding advantages of this invention are: This application avoids the huge starting resistance of the grinder caused by material accumulation by starting the upper and lower grinding components in stages, thus reducing the motor load. At the same time, during the grinding process, the coarse crushing and agitation of the upper grinding component effectively pre-treats the material, improves the grinding efficiency, and reduces the wear on the lower grinding component.

[0015] This application incorporates an overload protection mechanism between the upper and lower grinding components. By introducing this overload protection mechanism, the equipment can protect itself and recover quickly when faced with abnormal resistance, thus avoiding downtime and equipment damage and improving the stability and reliability of production. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall axial structure of the present invention.

[0017] Figure 2 This is a schematic diagram of the overall forward structure of the present invention.

[0018] Figure 3 This is a schematic diagram of the connection structure between the grinding cylinder and the base of the present invention.

[0019] Figure 4 This is a schematic diagram of the cover plate connection structure of the present invention.

[0020] Figure 5 This is a schematic diagram of the axial cross-sectional structure of the grinding cylinder of the present invention.

[0021] Figure 6 This is a schematic diagram of the front cross-sectional structure of the grinding cylinder of the present invention.

[0022] Figure 7 This is a schematic diagram of the grinding component structure of the present invention.

[0023] Figure 8 This is a schematic diagram of the axial structure of the grinding assembly of the present invention.

[0024] Figure 9 This is a schematic diagram of the forward structure of the grinding assembly of the present invention.

[0025] Figure 10 This is a schematic diagram of the filter plate structure of the present invention.

[0026] Figure 11 This is a schematic diagram of the connecting sleeve connection structure of the present invention.

[0027] The following are the labeling elements in the diagram: 1. Grinding cylinder; 2. Drive shaft; 3. Upper grinding assembly; 301. Sleeve; 302. Blade; 303. Grinding column; 304. Limiting rod; 4. Lower grinding assembly; 401. Grinding disc; 402. Cone; 403. Sphere; 404. Groove; 405. Filter plate; 5. Overload protection mechanism; 501. Bushing; 502. First connecting shaft; 503. Connecting sleeve; 504. Second connecting shaft; 505. First limiting pin; 506. Limiting groove; 507. Second limiting pin; 508. Guide groove; 509. Baffle; 510. Spring; 6. Chassis; 7. Lifting rod; 8. Base; 9. Telescopic rod; 10. Clamping block; 11. Fixing buckle; 12. Cover plate; 13. Through hole. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0029] Traditional coating grinding processes suffer from high starting resistance and high motor load when all the material to be ground is put into the grinding cylinder 1 at once and started directly. This can easily lead to difficulty in starting the motor, stalling, or even burnout. At the same time, uneven particle size, with large and fine particles being ground simultaneously, can easily result in low grinding efficiency, energy waste, and accelerated wear of the grinding components.

[0030] Please see the appendix Figure 1-11 This embodiment describes a coating grinding process to reduce the starting resistance of a vertical grinding mill. The process includes a grinding cylinder 1, inside which is a liftable drive shaft 2. The drive shaft 2 is equipped with an upper grinding assembly 3 and a lower grinding assembly 4. The upper grinding assembly 3 is located above the lower grinding assembly 4 and is used for coarse crushing of the material, while the lower grinding assembly 4 is used for fine grinding of the material. To address abnormal situations during the grinding process, an overload protection mechanism 5 is also provided between the lower grinding assembly 4 and the upper grinding assembly 3.

[0031] During the startup phase, drive shaft 2 is raised, causing the lower grinding component 4 to detach from or lightly contact the material deposited at the bottom of grinding cylinder 1. Subsequently, drive shaft 2 rotates, allowing the upper grinding component 3 to coarsely crush and agitate the material, effectively reducing startup resistance. Once the speed of drive shaft 2 stabilizes, it descends, allowing the lower grinding component 4 to begin fine grinding. During grinding, if the resistance experienced by the lower grinding component 4 exceeds the set value of the overload protection mechanism 5, the overload protection mechanism 5 will disconnect or slip the power transmission between the lower grinding component 4 and the upper grinding component 3, stopping the lower grinding component 4 from rotating, while only the upper grinding component 3 continues to operate. When the resistance decreases below the set value, the overload protection mechanism 5 restores power transmission, and the lower grinding component 4 continues fine grinding.

[0032] For ease of understanding, the following explains some key terms in this embodiment: Grinding cylinder 1, which usually refers to the container in a vertical grinder used to hold the material to be ground and the grinding media, is the main place where the grinding process takes place.

[0033] Drive shaft 2, which usually refers to the central shaft that connects to the power source and drives the grinding assembly to rotate, can realize lifting and lowering movements to adjust the position of the grinding assembly inside the grinding cylinder 1.

[0034] The upper grinding component 3, which is usually installed on the upper part of the drive shaft 2, is mainly used to perform preliminary crushing and agitation on the material to disperse material agglomerates and reduce the overall viscosity.

[0035] The lower grinding assembly 4, which is usually installed at the lower part of the drive shaft 2, is mainly used to finely grind the coarsely crushed material to achieve the required fineness.

[0036] Overload protection mechanism 5, which is usually installed in the power transmission path, can automatically disconnect or reduce power transmission when the load exceeds a preset value, so as to protect the equipment from damage.

[0037] This embodiment provides a grinding cylinder 1, the internal space of which is designed to accommodate the material to be ground and the grinding media. Inside the grinding cylinder 1, a liftable drive shaft 2 is installed. The lifting movement of the drive shaft 2 can be achieved through an external hydraulic system, pneumatic system, or mechanical screw mechanism, thereby precisely adjusting the vertical position of the grinding components mounted on it within the grinding cylinder 1. For example, the drive shaft 2 can be connected to an external lifting device, which uses a motor to drive a screw or hydraulic cylinder to achieve the up-and-down movement of the drive shaft 2.

[0038] An upper grinding assembly 3 and a lower grinding assembly 4 are mounted on the drive shaft 2. The upper grinding assembly 3 is positioned above the lower grinding assembly 4. The upper grinding assembly 3 is typically designed with a large agitation and preliminary crushing capacity, and may consist of multiple stirring blades. Its main function is to agitate the material, disperse agglomerates, and perform preliminary particle crushing. The lower grinding assembly 4 is designed with a fine grinding capacity, and may consist of a grinding disc 401, grinding rods, or grinding beads. Its main function is to further refine the material processed by the upper grinding assembly 3.

[0039] To ensure the stability of the grinding process and the safety of the equipment, an overload protection mechanism 5 is installed between the lower grinding assembly 4 and the upper grinding assembly 3. This mechanism is designed to monitor the resistance experienced by the lower grinding assembly 4 during the grinding process. When the resistance exceeds a preset safety threshold, the overload protection mechanism 5 can automatically respond, temporarily disconnecting the power transmission between the lower grinding assembly 4 and the upper grinding assembly 3 or causing slippage. When the resistance returns to a safe range, the mechanism can automatically or manually reset to restore power transmission.

[0040] When the grinding process starts, drive shaft 2 is first lifted. This lifting operation disconnects the lower grinding assembly 4 from the power source, preventing it from directly experiencing excessive starting resistance during the initial startup phase. Subsequently, drive shaft 2 is driven to rotate, at which point only the upper grinding assembly 3 performs coarse crushing and agitation on the material. The agitation effect of the upper grinding assembly 3 helps loosen the material deposit layer, reduces the overall viscosity of the material, and initially disperses large particles, thereby significantly reducing the starting resistance of the entire system.

[0041] Once the rotational speed of drive shaft 2 reaches a stable state, drive shaft 2 is controlled to descend. As drive shaft 2 descends, the lower grinding assembly 4 docks with the power source (drive shaft 2), and then the lower grinding assembly 4 begins to work, performing fine grinding on the material that has been pre-processed by the upper grinding assembly 3. At this stage, the initial resistance of the material has been effectively reduced, allowing the lower grinding assembly 4 to smoothly engage in fine grinding operations.

[0042] During the fine grinding process, the overload protection mechanism 5 continuously monitors the resistance experienced by the lower grinding component 4. Once the resistance exceeds a preset value, the overload protection mechanism 5 immediately activates, interrupting or reducing the power transmission from the upper grinding component 3 to the lower grinding component 4. At this time, the lower grinding component 4 stops rotating, while the upper grinding component 3 continues to rotate, agitating and coarsely crushing the material to eliminate the overload. When the material resistance decreases below the set value due to the continuous action of the upper grinding component 3, the overload protection mechanism 5 automatically or through the control system restores the power transmission between the lower and upper grinding components 4, allowing the lower grinding component 4 to restart fine grinding.

[0043] This process, by lifting the drive shaft 2 during startup, detaches the lower grinding component 4 from the bottom deposited material, allowing the upper grinding component 3 to perform coarse crushing and agitation first. This effectively reduces the starting resistance of the vertical grinder and avoids motor overload and damage. During the grinding process, an overload protection mechanism 5 is installed. When the resistance is too high, the lower grinding component 4 stops rotating, while only the upper grinding component 3 continues to work, thus protecting the grinding components and improving the stability and safety of the grinding process.

[0044] This application further proposes that the upper grinding assembly 3 includes a sleeve 301, the sleeve 301 is fixedly connected to the drive shaft 2, a blade 302 is fixedly connected to the outside of the sleeve 301, and a grinding column 303 is provided below the blade 302, and the grinding column 303 is fixedly connected to the sleeve 301.

[0045] Specifically, the sleeve 301, as the core support structure of the upper grinding assembly 3, is typically a hollow cylinder or tube. Its main function is to provide a stable base 8 for mounting and fixing the blades 302 and the grinding column 303. The blades 302 are the main working components of the upper grinding assembly 3 for coarse crushing and agitation. Their design shape can be optimized according to the characteristics of the material to be ground. The blades 302 are usually made of high-hardness, high-wear-resistant materials, such as cemented carbide, ceramics, or tool steel with special surface treatment, to resist material wear and impact, extend service life, and maintain efficient crushing capacity. The number, size, thickness, and arrangement angle and spacing of the blades 302 on the sleeve 301 all affect their crushing and agitation effect on the material. The grinding column 303 is located below the blades 302 and works in conjunction with the blades 302 to further refine and mix the material that has been pre-treated by the blades 302. The presence of the grinding column 303 increases the shearing and squeezing action of the material within the grinding cylinder 1, helping to break up material clumps and promote uniform dispersion and flow of the material. This application further proposes an optimized structure for the upper grinding assembly 3. Specifically, the sleeve 301 is externally fixedly connected to a limiting rod 304, there are multiple sets of blades 302, and the multiple sets of blades 302 are equidistantly arranged on the limiting rod 304. The grinding column 303 is an inverted L-shaped structure, and the grinding column 303 is located on the periphery of the lower grinding assembly.

[0046] The limiting rod 304 primarily serves to support and position the multiple sets of blades 302, ensuring that the blades 302 maintain a stable position and spacing during rotation. This prevents the blades 302 from shifting or deforming due to stress, thereby guaranteeing the uniformity and efficiency of coarse crushing and agitation. Its number and distribution can be designed according to the number of blades 302 and the stress conditions to provide sufficient support.

[0047] The grinding column 303 is shaped like an inverted letter "L". This special L-shaped structure, especially the inverted form, increases the contact area and agitation effect between the grinding column 303 and the material, particularly in the bottom area of ​​the grinding cylinder 1. Its shape helps guide material flow better, prevents material accumulation below the grinding column 303, and enhances the ability to agitate and crush the material, further reducing start-up resistance. The grinding column 303 is arranged in the outer area of ​​the lower grinding assembly. Placing the grinding column 303 on the periphery of the lower grinding assembly allows it to act more effectively on the material at the edge of the grinding cylinder 1 during the coarse crushing stage, which may be more prone to sedimentation or agglomeration at startup. This layout facilitates more comprehensive agitation and pretreatment of the material at the bottom of the entire grinding cylinder 1 during the initial startup phase, creating favorable conditions for subsequent fine grinding and further reducing start-up resistance.

[0048] This application proposes that the lower grinding assembly 4 includes a grinding disc 401, a cone 402 and a ball 403 are fixedly connected below the grinding disc 401, a groove 404 is opened on the side of the grinding disc 401, and a filter plate 405 is rotatably connected below the grinding disc 401, and the filter plate 405 is fixedly connected to the grinding cylinder 1.

[0049] Specifically, the grinding disc 401 is the core component of the lower grinding assembly 4, and its main function is to provide the grinding surface required for fine grinding. The grinding disc 401 is typically circular or polygonal, and its surface can be designed to be smooth, textured, or have a specific geometry to increase the shearing and impact between the material and the grinding media. During the grinding process, the grinding disc 401 rotates at high speed, pushing the material against the wall of the grinding cylinder 1 through centrifugal force, and interacting with the grinding media (such as grinding beads) to achieve material refinement. The grinding disc 401 is typically made of high-hardness, wear-resistant materials, such as ceramics or alloy steel, to ensure its service life and grinding efficiency.

[0050] A cone 402 and a sphere 403 are fixedly connected below the grinding disc 401. The main function of these structural components is to optimize the flow path of the material below the grinding disc 401, increase the grinding time and grinding area, and further crush and disperse the material. Grooves 404 are formed on the side of the grinding disc 401. These grooves 404 are designed to improve the flowability of the material in the edge area of ​​the grinding disc 401, promote the discharge of ground material, and introduce new material to be ground. A filter plate 405 is rotatably connected below the grinding disc 401, and the filter plate 405 is fixedly connected to the grinding cylinder 1. The main function of the filter plate 405 is to separate the material that has reached the specified fineness from the unground or coarse particles. When the grinding disc 401 rotates, the filter plate 405 remains stationary, forming a fixed filtration barrier. The material is refined by the grinding disc 401 and discharged through the pores of the filter plate 405, while larger particles are blocked in the grinding area and continue to be ground.

[0051] This application further proposes that the overload protection mechanism 5 includes a bushing 501, which is fixedly connected to the drive shaft 2. The bushing 501 has a cavity inside. A first connecting shaft 502 is fixedly connected to the bushing 501. A connecting sleeve 503 is fitted below the first connecting shaft 502. A second connecting shaft 504 is fitted below the connecting sleeve 503. A first limiting pin 505 is fixedly connected to the first connecting shaft 502. A limiting groove 506 that cooperates with the first connecting pin is provided above the connecting sleeve 503. A second limiting pin 507 is fixedly connected to the second connecting shaft 504. A guide groove 508 for the second limiting pin 507 to slide is opened on the connecting sleeve 503. The second connecting shaft 504 is fixedly connected to the lower grinding assembly. A baffle 509 is fixedly connected to the second connecting shaft 504. A spring 510 that applies upward force to the connecting sleeve 503 is provided between the baffle 509 and the connecting sleeve 503.

[0052] Specifically, the bushing 501 is fixedly connected to the drive shaft 2 and serves as the main structure of the overload protection mechanism 5, bearing and transmitting the rotational power from the drive shaft 2. Its internal cavity provides installation space and movement trajectory for components such as the first connecting shaft 502, connecting sleeve 503, second connecting shaft 504, and spring 510, ensuring that these components can move relative to each other within the bushing 501. The first connecting shaft 502 is fixedly connected to the bushing 501 and rotates with it, serving as the first link in transmitting power from the drive shaft 2 to the overload protection mechanism 5. The connecting sleeve 503 is fitted below the first connecting shaft 502 and is a key component for disconnecting and restoring power transmission. It cooperates with the first limiting pin 505 through a limiting groove 506, transmitting power during normal operation and allowing relative movement during overload. The second connecting shaft 504 is fitted below the connecting sleeve 503 and fixedly connected to the lower grinding assembly, transmitting power to the lower grinding assembly. The first limiting pin 505 is fixedly connected to the first connecting shaft 502 and engages with the limiting groove 506 on the connecting sleeve 503. During normal operation, the first limiting pin 505 engages with the limiting groove 506, achieving synchronous rotation between the first connecting shaft 502 and the connecting sleeve 503. When an overload occurs, if the connecting sleeve 503 rotates relative to the first connecting shaft 502, the first limiting pin 505 will disengage from the limiting groove 506 or slip within the groove, thereby disconnecting or slipping the power transmission. The limiting groove 506 is located above the connecting sleeve 503 and is used to receive the first limiting pin 505. Its shape and depth design determine the response sensitivity and slippage characteristics of the overload protection mechanism 5. The second limiting pin 507 is fixedly connected to the second connecting shaft 504 and slides within the guide groove 508 on the connecting sleeve 503. It ensures the axial relative position of the connecting sleeve 503 and the second connecting shaft 504, and allows them to rotate or slide relative to each other within a certain range, thereby achieving the disconnection or slippage of power transmission. The guide groove 508 is located on the connecting sleeve 503, allowing the second limiting pin 507 to slide. Its design allows the second connecting shaft 504 to rotate or axially displace relative to the connecting sleeve 503 to a certain extent under overload, thereby achieving the disconnection or slippage of power transmission. The baffle 509 is fixedly connected to the second connecting shaft 504, providing a support surface for the spring 510, enabling the spring 510 to apply an upward force to the connecting sleeve 503. The spring 510 is located between the baffle 509 and the connecting sleeve 503, applying an upward preload force to the connecting sleeve 503. This force ensures that, under normal operating conditions, the first limiting pin 505 can stably engage with the limiting groove 506, maintaining power transmission. When an overload occurs, if the resistance exceeds the preload of spring 510, the connecting sleeve 503 will move downward or rotate relative to it, causing the first limit pin 505 to disengage from the limit groove 506, thereby disconnecting or slipping the power transmission. The spring constant and preload of spring 510 are key parameters that determine the overload protection setting.

[0053] This application further proposes that there are four of each of the first limiting pin 505 and the second limiting pin 507, and that the side of the groove 404 is provided with an arc-shaped slope.

[0054] Specifically, the first limiting pin 505 and the second limiting pin 507 are key components in the overload protection mechanism 5 used to transmit torque and achieve separation during overload. Setting the number of both the first limiting pin 505 and the second limiting pin 507 to four means that four pairs of pin-groove mating structures are evenly distributed in the circumferential direction. This multi-point contact design, compared to single-point or two-point contact, can more evenly distribute the transmitted torque load, reduce stress concentration on a single pin or groove, thereby improving the load-bearing capacity and operational stability of the mechanism. Furthermore, the multi-pin structure also enhances the reliability of the mechanism; even if one pin or groove experiences slight wear, the other pins can still effectively transmit power, preventing the entire mechanism from stopping due to localized failure. The groove 404 refers to the limiting groove 506 on the connecting sleeve 503 that mates with the first limiting pin 505. An arc-shaped ramp is provided on the side of the limiting groove 506, which optimizes the engagement and disengagement process between the first limiting pin 505 and the limiting groove 506. When the grinding resistance exceeds the set value, the first limit pin 505 will gradually slide out of the limit groove 506 along the arc-shaped ramp under the action of torque, achieving a smooth disconnection of power transmission rather than a sudden impact separation. Similarly, when the resistance decreases and power transmission is restored, the first limit pin 505 can also smoothly re-enter the limit groove 506 along the arc-shaped ramp.

[0055] This application proposes a structure in which a drive shaft 2 is fixedly connected to a housing 6, a lifting rod 7 is connected to the side of the housing 6, a base 8 is fixedly connected below the lifting rod 7, and the grinding cylinder 1 is located on the side of the lifting rod 7. Specifically, the drive shaft 2 is fixedly connected to the housing 6, which means that the rotational power source (e.g., a motor) and transmission mechanism (e.g., a gear set) of the drive shaft 2 are integrated inside the housing 6. This fixed connection ensures the stability of power transmission and structural rigidity of the drive shaft 2 during rotation and lifting, avoiding vibration or reduced transmission efficiency due to loose connections. The housing 6 is typically made of high-strength materials, capable of withstanding the torque and radial force generated during the high-speed rotation and grinding of the drive shaft 2. The lifting rod 7, connected to the side of the housing 6, is the core component for realizing the vertical lifting of the drive shaft 2. The lifting rod 7 can be a hydraulic rod, a pneumatic rod, a lead screw transmission mechanism, or a gear and rack mechanism, etc., and its function is to provide precise and controllable vertical displacement, enabling the drive shaft 2 to be accurately raised or lowered according to process requirements. By connecting the lifting rod 7 to the housing 6, the drive shaft 2 and its internal grinding components can be synchronously raised and lowered, ensuring the smoothness of the lifting process. A base 8 is fixedly connected to the bottom of the lifting rod 7. As the main support structure of the entire vertical grinder, the base 8 is typically made of heavy steel or cast iron, possessing sufficient weight and rigidity to provide the overall stability required for equipment operation. The base 8 effectively absorbs and disperses vibrations and impacts generated during the grinding process, ensuring the stability of the equipment under high-speed operation and heavy load conditions, preventing overturning or displacement. The grinding cylinder 1 is located on the side of the lifting rod 7. This layout allows the grinding cylinder 1 and the lifting mechanism of the drive shaft 2 to be spatially independent yet mutually supportive. As the container for material grinding, the side layout of the grinding cylinder 1 facilitates material feeding and discharging, while reserving sufficient space for the vertical movement of the drive shaft 2. This structural design helps optimize the overall footprint of the equipment and may facilitate maintenance and cleaning.

[0056] This application further proposes that one side of the grinding cylinder 1 is hinged to the base 8, and a telescopic rod 9 is installed between the other side of the grinding cylinder 1 and the base 8.

[0057] Specifically, the grinding cylinder 1 is hinged to the base 8 on one side, meaning that the grinding cylinder 1 is connected to the base 8 through one or more hinge mechanisms, allowing the grinding cylinder 1 to rotate or tilt around the hinge point. The telescopic rod 9 installed between the other side of the grinding cylinder 1 and the base 8 is a variable-length support or drive device. This telescopic rod 9 can be a hydraulic cylinder, pneumatic cylinder, electric actuator, or a mechanical telescopic support rod with a locking mechanism. Its function is to control the tilt angle and position of the grinding cylinder 1. When it is necessary to tilt the grinding cylinder 1, the telescopic rod 9 can be shortened or extended, allowing the grinding cylinder 1 to tilt around the hinge point; when the grinding cylinder 1 returns to its working position, the telescopic rod 9 can be extended and locked to provide stable support, ensuring that the grinding cylinder 1 maintains a fixed posture during grinding. The installation position and stroke of the telescopic rod 9 should match the required tilt angle of the grinding cylinder 1 and have sufficient load-bearing capacity and control precision.

[0058] This application further proposes that, in order to ensure the absolute stability of the grinding cylinder 1 in the working state, clamping blocks 10 are provided on both sides of the grinding cylinder 1. These clamping blocks 10 are structural components specifically designed to firmly fix the grinding cylinder 1 to the base 8. They are usually made of high-strength metal materials, and their inner sides may be designed with arc-shaped or planar structures that match the outer wall of the grinding cylinder 1 to provide a larger contact area and a more uniform clamping force.

[0059] This application further proposes that a fixing buckle 11 is fixedly connected to the lifting rod 7, and two sets of symmetrically distributed cover plates 12 are rotatably connected to the fixing buckle 11. A through hole 13 that cooperates with the drive shaft 2 is provided between the two cover plates 12.

[0060] Specifically, the fixing buckle 11 is designed to be firmly connected to the lifting rod 7, and its function is to provide a stable support and connection point for the subsequently installed cover plate 12. Two sets of symmetrically distributed cover plates 12 are rotatably connected to the fixing buckle 11. The main function of these cover plates 12 is to cover and protect the exposed portion of the drive shaft 2 in the area of ​​the lifting rod 7. The rotatable connection can be achieved through structures including, but not limited to, hinges, pivots, or pins, allowing the cover plate 12 to rotate around an axis for easy opening or closing. A through hole 13 is provided between the two cover plates 12 to mate with the drive shaft 2. This through hole 13 is a through channel reserved for the drive shaft 2 when the two sets of cover plates 12 are closed. The size and shape of the through hole 13 are precisely designed to match the shape of the drive shaft 2, ensuring that the drive shaft 2 can pass through smoothly and without obstruction during lifting.

[0061] The following example will provide a more detailed explanation of the above technical solution: In a paint production workshop, a vertical grinding mill is used to grind a batch of paint materials. The grinding cylinder 1 is already loaded with the paint materials to be ground and grinding media. Due to the equipment being shut down for a period of time, the solid particles in the materials and the grinding media have formed a dense layer of sediment at the bottom of the grinding cylinder 1 under the action of gravity.

[0062] To initiate the grinding process, the operator starts the equipment. At this point, the grinder does not directly drive the grinding components to rotate within the deposit; instead, a lifting mechanism is activated first. This mechanism raises the drive shaft 2. As the drive shaft 2 rises, the lower grinding component 4 located below it is lifted away from the deposited material at the bottom of the grinding cylinder 1, or remains in only slight contact with the surface of the deposited material.

[0063] When drive shaft 2 is in the raised position, the main motor starts driving drive shaft 2 to rotate. During this stage, only the upper grinding assembly 3 is in contact with and working on the material. The upper grinding assembly 3 includes a sleeve 301 fixedly connected to drive shaft 2. Multiple sets of blades 302 are fixedly connected to the outside of sleeve 301, and these blades 302 are equidistantly arranged on the limiting rod 304. Below the blades 302, grinding columns 303 are also fixedly connected to sleeve 301. These grinding columns 303 have an inverted L-shaped structure and are located around the lower grinding assembly 4. The rotation of the upper grinding assembly 3 causes the blades 302 and grinding columns 303 to coarsely crush and agitate the material in the upper part of the grinding cylinder 1. This pretreatment effectively loosens the surface layer of the deposited material and initially disperses the material, thus significantly reducing the resistance that drive shaft 2 needs to overcome during startup. Compared with the traditional direct start-up method, this step-by-step start-up avoids excessive load on the motor in the initial startup stage and solves the problem of high starting resistance.

[0064] Once the rotational speed of drive shaft 2 stabilizes and the material has undergone initial agitation and coarse crushing by upper grinding component 3, the control system instructs drive shaft 2 to slowly descend. As drive shaft 2 descends, lower grinding component 4 gradually enters the material layer and begins fine grinding. Lower grinding component 4 includes a grinding disc 401, with a cone 402 and a ball 403 fixedly connected below it. Grooves 404 are formed on the side of grinding disc 401. A filter plate 405 is also rotatably connected below grinding disc 401 and is fixedly connected to grinding cylinder 1. The fine grinding action of lower grinding component 4 further refines the material particles under the action of the grinding media, achieving the desired particle size.

[0065] During the fine grinding process, the system continuously monitors the resistance experienced by the lower grinding component 4. If the resistance experienced by the lower grinding component 4 suddenly increases and exceeds the preset overload protection value due to factors such as localized material accumulation, sudden viscosity changes, or uneven distribution of grinding media, the overload protection mechanism 5 will be activated immediately. This mechanism includes a bushing 501 fixedly connected to the drive shaft 2. The bushing 501 has a cavity inside. A first connecting shaft 502 is fixedly connected to the bushing 501. A connecting sleeve 503 is fitted below the first connecting shaft 502. A second connecting shaft 504 is fitted below the connecting sleeve 503. Four first limiting pins 505 are fixedly connected to the first connecting shaft 502. A limiting groove 506 that mates with the first limiting pins 505 is provided on the upper part of the connecting sleeve 503. The side of the limiting groove 506 has an arc-shaped ramp. Four second limiting pins 507 are fixedly connected to the second connecting shaft 504. A guide groove 508 for the second limiting pins 507 to slide is provided on the connecting sleeve 503. The second connecting shaft 504 is fixedly connected to the lower grinding assembly 4. A baffle 509 is also fixedly connected to the second connecting shaft 504, and a spring 510, which applies upward force to the connecting sleeve 503, is provided between the baffle 509 and the connecting sleeve 503. When the resistance is too high, the overload protection mechanism 5, through the cooperation of the first limiting pin 505 and the limiting groove 506, and the action of the spring 510, temporarily disconnects the power transmission between the lower grinding assembly 4 and the upper grinding assembly 3 or causes slippage. At this time, the lower grinding assembly 4 stops rotating, while the upper grinding assembly 3 continues to rotate, agitating and coarsely crushing the material to eliminate the resistance source. This mechanism effectively prevents equipment damage due to localized overload and ensures the continuity of the grinding process.

[0066] When the resistance drops below the set value, the overload protection mechanism 5, under the action of the spring 510, restores the power transmission between the lower grinding assembly 4 and the upper grinding assembly 3, and the lower grinding assembly 4 restarts fine grinding. The entire process requires no manual intervention, achieving automated protection and recovery.

[0067] The entire grinding machine has a stable structure. The drive shaft 2 is fixedly connected to the housing 6, and a lifting rod 7 is connected to the side of the housing 6. A base 8 is fixedly connected below the lifting rod 7. One side of the grinding cylinder 1 is hinged to the base 8, and a telescopic rod 9 is installed between the other side and the base 8. Both sides of the grinding cylinder 1 are equipped with clamping blocks 10 that are threaded to the base 8 to ensure the stability and maintainability of the grinding cylinder 1. A fixing buckle 11 is fixedly connected to the lifting rod 7, and two sets of symmetrically distributed cover plates 12 are rotatably connected to the fixing buckle 11. A through hole 13 that mates with the drive shaft 2 is provided between the two cover plates 12, further improving the overall stability and operational safety of the equipment.

[0068] Through the aforementioned process, this grinding mill avoids the significant starting resistance caused by material accumulation in traditional grinding mills, thus reducing the motor load. During the grinding process, the coarse crushing and agitation of the upper grinding component 3 effectively pre-treats the material, improving grinding efficiency and reducing wear on the lower grinding component 4. The introduction of the overload protection mechanism 5 ensures that the equipment can self-protect and quickly recover when faced with abnormal resistance, avoiding downtime and equipment damage, and improving production stability and reliability.

[0069] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A coating grinding process for reducing the starting resistance of a vertical grinding mill, characterized in that: The device includes a grinding cylinder (1), which has a liftable drive shaft (2) inside. The drive shaft (2) has an upper grinding component (3) and a lower grinding component (4). The upper grinding component (3) is located above the lower grinding component (4) and is used to coarsely crush the material. The lower grinding component (4) is used to finely grind the material. An overload protection mechanism (5) is provided between the lower grinding component (4) and the upper grinding component (3). When starting, the drive shaft (2) is raised to a position where the lower grinding component (4) is disengaged from or lightly contacts the material deposited at the bottom of the grinding cylinder (1), and the drive shaft (2) is driven to rotate. The upper grinding component (3) first coarsely crushes and agitates the material to reduce the starting resistance. After the speed of the drive shaft (2) stabilizes, the drive shaft (2) is controlled to descend, so that the lower grinding assembly (4) starts to work and performs fine grinding; During the grinding process, when the resistance of the lower grinding component (4) is greater than the set value of the overload protection mechanism (5), the overload protection mechanism (5) disconnects or slips the power transmission between the lower grinding component (4) and the upper grinding component (3), the lower grinding component (4) stops rotating, and only the upper grinding component (3) continues to rotate; when the resistance is reduced to below the set value, the overload protection mechanism (5) restores the power transmission between the lower grinding component (4) and the upper grinding component (3), and continues fine grinding.

2. The coating grinding process for reducing the starting resistance of a vertical grinding mill according to claim 1, characterized in that: The upper grinding assembly (3) includes a sleeve (301), which is fixedly connected to the drive shaft (2). A blade (302) is fixedly connected to the outside of the sleeve (301), and a grinding column (303) is provided below the blade (302). The grinding column (303) is fixedly connected to the sleeve (301).

3. The coating grinding process for reducing the starting resistance of a vertical grinding mill according to claim 2, characterized in that: The sleeve (301) is fixedly connected to a limiting rod (304). There are multiple sets of blades (302), and the multiple sets of blades (302) are equidistantly arranged on the limiting rod (304). The grinding column (303) is an inverted L-shaped structure, and the grinding column (303) is located on the periphery of the lower grinding assembly.

4. The coating grinding process for reducing the starting resistance of a vertical grinding mill according to claim 1, characterized in that: The lower grinding assembly includes a grinding disc (401), a cone (402) and a ball (403) are fixedly connected below the grinding disc (401), a groove (404) is opened on the side of the grinding disc (401), and a filter plate (405) is rotatably connected below the grinding disc (401), and the filter plate (405) is fixedly connected to the grinding cylinder (1).

5. The coating grinding process for reducing the starting resistance of a vertical grinding mill according to claim 1, characterized in that: The overload protection mechanism (5) includes a bushing (501), which is fixedly connected to the drive shaft (2). The bushing (501) has a cavity inside. A first connecting shaft (502) is fixedly connected to the bushing (501). A connecting sleeve (503) is fitted below the first connecting shaft (502). A second connecting shaft (504) is fitted below the connecting sleeve (503). A first limiting pin (505) is fixedly connected to the first connecting shaft (502). A limit pin (505) is provided above the connecting sleeve (503). A limiting groove (506) that cooperates with the first connecting pin; a second limiting pin (507) fixedly connected to the second connecting shaft (504); a guide groove (508) for sliding the second limiting pin (507) on the connecting sleeve (503); the second connecting shaft (504) fixedly connected to the lower grinding assembly; a baffle (509) fixedly connected to the second connecting shaft (504); and a spring (510) for the connecting sleeve (503) to exert upward force between the baffle (509) and the connecting sleeve (503).

6. The coating grinding process for reducing the starting resistance of a vertical grinding mill according to claim 5, characterized in that: There are four of the first limiting pin (505) and four of the second limiting pin (507), and the limiting groove (506) has an arc-shaped ramp on the side.

7. The coating grinding process for reducing the starting resistance of a vertical grinding mill according to claim 1, characterized in that: The drive shaft (2) is fixedly connected to the housing (6), the side of the housing (6) is connected to the lifting rod (7), the base (8) is fixedly connected below the lifting rod (7), and the grinding cylinder (1) is located on the side of the lifting rod (7).

8. The coating grinding process for reducing the starting resistance of a vertical grinding mill according to claim 7, characterized in that: One side of the grinding cylinder (1) is hinged to the base (8), and a telescopic rod (9) is installed between the other side of the grinding cylinder (1) and the base (8).

9. The coating grinding process for reducing the starting resistance of a vertical grinding mill according to claim 8, characterized in that: The grinding cylinder (1) is provided with clamping blocks (10) on both sides, and the clamping blocks (10) are threadedly connected to the base (8).

10. A coating grinding process for reducing the starting resistance of a vertical grinding mill according to claim 7, characterized in that: The lifting rod (7) is fixedly connected to a fixing buckle (11), and two sets of symmetrically distributed cover plates (12) are rotatably connected to the fixing buckle (11). A through hole (13) that cooperates with the drive shaft (2) is provided between the two cover plates (12).

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