Permanent magnet driving stirring device

Abstract

The permanent magnet driving stirring device comprises a stirring tank, a stirring machine frame, a stirring driving part, a magnetic suspension stirrer and a driving control system, the stirring tank comprises an inner tank and an outer tank, and the magnetic suspension stirrer is clamped between the inner tank and the outer tank; magnets are arranged at the bottoms of the inner tank and the outer tank, provide buoyancy for the magnetic suspension stirrer and comprise stirring blades, blade supporting plates and magnets, and the magnets at the bottoms of the inner tank and the outer tank have focusing magnetic fields with the same polarity as those of the magnets of the magnetic suspension stirrer; the stirring driving component comprises a permanent magnet direct drive motor, a driving connecting flange, a rotating disc and a magnetic driving head; the motor is connected with the lower end face of the driving connecting flange, and the upper end face of the driving connecting flange is fastened to the rotating disc. The magnetic driving head comprises a yoke, inclined magnetic steel and transverse magnetic steel, a complete circulating magnetic circuit is formed, and the magnetic suspension stirrer is driven to generate a synchronous rotating speed. Magnetic force is adopted for guiding stirring, the blades suspend under the action of magnetic force, efficiency is higher, and no transmission chain device exists.

Description

Technical Field

[0001] This invention relates to a stirring system, and more particularly to a stirring device for a stirring system. Background Technology

[0002] Mixers are widely used in industries such as chemical, water treatment, pharmaceutical, metallurgy, cosmetics, and food. Their function is to mix liquids of different components within a mixing tank to achieve a liquid mixture of a target viscosity, or to induce physical and chemical changes within the mixing tank. To achieve ideal mixing results, the most important factors are achieving a reasonable mixing speed and controlling the flow trajectory of the liquid within the mixing tank. Furthermore, in precision mixing applications, the composition of the liquid must be strictly controlled during the mixing process to prevent the introduction of external impurities.

[0003] Traditional mixers typically use three-phase asynchronous motors to power the agitator. The motor and agitator are usually connected via a reducer and coupling for kinetic energy transmission. This method has low transmission efficiency and high energy consumption. Reducer failures are frequent, and when the reducer oil seal or the seal on the agitator shaft on the mixing tank fails, oil leaks into the mixing tank, affecting the purity of the mixed medium. In the pharmaceutical and chemical industries, the liquids being mixed are often corrosive, which can damage the seal at the agitator shaft or cause spillage outside the tank during mixing, resulting in environmental pollution or corrosion of external equipment. Furthermore, the asynchronous motor cannot adjust its operating state according to changes in the viscosity and volume of the mixed medium, leading to low unit efficiency and significant energy waste.

[0004] Moreover, the current mixer's power unit is located at the top of the mixing tank and is mechanically connected to the mixing tank. When cleaning the inside of the mixing tank, it is necessary to remove related parts, resulting in a waste of time in maintenance.

[0005] Furthermore, traditional mixers typically use a stirring paddle that rotates along the axis of the mixing tank. The stirring paddle drives the liquid inside the mixing tank to rotate, generating centrifugal force, and then the liquid flows back to the center to achieve the purpose of mixing. This method causes liquids of different densities to flow in fixed layers, resulting in uneven mixing and low mixing efficiency. Summary of the Invention

[0006] The purpose of this invention is to provide a permanent magnet driven stirring device to solve the problems of poor sealing performance, high failure rate, low efficiency, and frequent contamination of the stirring fluid due to leakage of lubricating oil and coolant in the driving system in industrial fields, especially chemical, food, and pharmaceutical industries. In addition, it improves stirring efficiency and mixing effect, and reduces vibration and noise.

[0007] Therefore, the present invention provides a permanent magnet driven stirring device, comprising: a stirring tank, a stirring frame, a stirring drive component, a magnetic levitation stirrer, and a drive control system; the stirring tank includes an inner tank and an outer tank, which are completely separable, and the magnetic levitation stirrer is rotatably clamped in the gap between the bottom of the inner tank and the bottom of the outer tank; magnets are provided at the bottom of both the inner tank and the bottom of the outer tank, and are completely covered by a sealing cover to provide buoyancy for the magnetic levitation stirrer; the magnetic levitation stirrer includes stirring blades, a blade support plate, and magnets, and the magnets at the bottom of the inner tank and the bottom of the outer tank both have a focused magnetic field with the same polarity as the focused magnetic field of the magnets of the magnetic levitation stirrer; the stirring... The stirring drive component includes a permanent magnet direct drive motor, a drive connection flange, a rotating disk, and magnetic drive heads. The permanent magnet direct drive motor is connected to the lower end face of the drive connection flange via a shaft extension, and the upper end face of the drive connection flange is fastened to the rotating disk. Thus, the permanent magnet direct drive motor drives the magnetic drive heads, which are evenly distributed on the rotating disk, to rotate. The magnetic drive head includes a yoke, oblique magnets, and transverse magnets. The oblique magnets provide a focusing effect, preventing the magnetic field from dissipating and enhancing the magnetic force. The yoke, the oblique magnets, the transverse magnets, and the stirring blades form a complete circulating magnetic circuit, thereby providing a uniformly distributed attractive force to the magnetic levitation stirrer in the circumferential direction, driving the magnetic levitation stirrer to generate a synchronous rotation speed.

[0008] As a preferred embodiment, the permanent magnet driven stirring device further includes an adjusting cylinder, a cylinder support, and a suspension adjusting magnet. The cylinder support is located at the lower part of the outer tank of the stirring tank and is used to support the adjusting cylinder to push the suspension adjusting magnet. The closer the suspension adjusting magnet is to the magnet at the bottom of the outer tank, the greater the repulsive force it provides, and the greater the levitation force of the magnetic levitation stirrer.

[0009] In a preferred embodiment, the magnetic drive head includes two poles arranged vertically, namely an N pole and an S pole. Each pole includes a yoke, two oblique magnets, and a transverse magnet sandwiched between the two oblique magnets. The transverse magnet of the N pole is oriented towards the stirring blade, and the oblique magnets on both sides are oriented inward. The transverse magnet of the S pole is oriented towards the yoke, and the oblique magnets on both sides are oriented outward. Furthermore, the stirring blade connects the magnetic circuits of the upper and lower poles of the stirring drive component.

[0010] In a preferred embodiment, both the magnet at the bottom of the inner tank and the magnet at the bottom of the outer tank include a magnet ring, an inner arc repulsive magnet, and an outer arc repulsive magnet, and the magnet ring is fitted into the gap between the inner arc repulsive magnet and the outer arc repulsive magnet; the magnet of the magnetic levitation stirrer includes an outer arc repulsive magnet, an inner arc repulsive magnet, and a magnet ring, and the outer arc repulsive magnet, inner arc repulsive magnet, and magnet ring of the magnetic levitation stirrer are disposed on the same plane of the blade support plate, and the magnet ring of the magnetic levitation stirrer is fitted into the gap between the outer arc repulsive magnet and the inner arc repulsive magnet of the magnetic levitation stirrer.

[0011] In a preferred embodiment, the magnetic ring, inner arc repulsive magnet, and outer arc repulsive magnet at the bottom of the inner tank and the bottom of the outer tank are completely covered by magnetic steel sealing cover plates. The magnetic levitation stirrer also includes a blade iron ring located at the center of the blade support plate. The outer arc repulsive magnet and inner arc repulsive magnet of the magnetic levitation stirrer are glued to the recess formed by the magnetic steel sealing cover plate, blade iron ring, and blade support plate of the magnetic levitation stirrer using anaerobic structural adhesive. Furthermore, the magnetic steel sealing cover plate at the bottom of the inner tank, the magnetic steel sealing cover plate at the bottom of the outer tank, and the magnetic steel sealing cover plate of the magnetic levitation stirrer are all annular structures with through holes evenly distributed on the inner and outer rings. These holes are fixed to the corresponding threaded holes of the inner tank, the outer tank, and the magnetic levitation stirrer, respectively, to press the sealing rings of the mating surfaces together.

[0012] As a preferred embodiment, the inner tank has a uniformly distributed first guide groove on its peripheral wall, a uniformly distributed second guide groove on its bottom wall, and a third guide groove located at the center of the bottom wall of the inner tank. The first and second guide grooves are elongated holes, while the third guide groove is a circular hole. At least one annular guide plate is provided on the peripheral wall of the outer tank. Under the combined action of the stirring blades and centrifugal force, the liquid inside the stirring tank is stirred and flows sequentially through the first guide groove, the second guide groove, the third guide groove, and the guide plate, and then flows back, thus repeating the cycle.

[0013] As a preferred embodiment, the number of stirring blades is 12, and the number of magnetic drive heads is 6.

[0014] As a preferred embodiment, the N poles of both the inner and outer arc repulsive magnets point towards the matching magnetic ring. The volume of the magnetic ring is approximately 1 / 3 to 1 / 2 of the total volume of the matching magnets to ensure its magnetic saturation strength, thereby increasing the repulsive force between the magnetic levitation stirrer and the inner and outer tanks.

[0015] As a preferred embodiment, the magnet ring can be made as a single piece or divided into uniform segments; and the maximum width of both the inner arc repulsive magnet and the outer arc repulsive magnet is guaranteed to be less than 100mm.

[0016] As a preferred embodiment, the drive connection flange includes a lower disc, an upper annular flange, and stiffening plates for connecting the disc and the annular flange. The stiffening plates are perpendicular to the disc and the annular flange and are evenly distributed along the circumference of the annular flange and the disc.

[0017] The outer ring of the annular flange has evenly distributed through holes for connecting the rotating disk, and the center of the disk is provided with a keyway bushing for connecting the shaft extension of the permanent magnet direct drive motor.

[0018] In this invention, the terms magnet and magnetic steel are used in their general sense in the art, and magnet is a superordinate concept of magnetic steel.

[0019] In existing technologies, the drive unit of a mixer generally uses a three-phase asynchronous motor to transmit power to the mixing blade through a reducer. This method has no adjustable speed, suffers significant intermediate losses, and has a high failure rate for the reducer. This invention uses a variable frequency permanent magnet synchronous motor to drive a permanent magnet to rotate. The rotating magnetic field then drives the suspended mixing blade inside the mixing tank. This not only offers high efficiency but also adjustable speed, eliminates friction and the need for lubrication and sealing devices, thus reducing the failure rate.

[0020] Traditional mixers typically use a coupling to connect the motor and reducer, which is cumbersome for alignment, and the reducer and mixer connecting shafts are vertically connected. With the reducer's output shaft pointing downwards, it generally uses a forced lubrication system or has an oil replenishment tank. Due to the reducer's compact design and weak heat dissipation, coupled with its small speed ratio, high speed, and large heat generation, lubricating oil and seal failures are easily caused. Oil leakage due to downward-facing oil seal failure can severely contaminate the environment and the materials being mixed. This invention utilizes a rotating magnetic field to drive a ferromagnetic stirring paddle inside the mixing tank. Without mechanical connections, the mixing tank is completely sealed during operation, thoroughly isolating it from the outside environment. This prevents leakage of substances such as lubricating oil and coolant from the outside of the mixing tank, and also prevents the evaporation and splashing of substances inside the mixing tank onto the outside, thus avoiding impacts on the environment, equipment, and personnel health.

[0021] In traditional cooling tower equipment, the output shaft of the vertically mounted reducer is upward, making lubrication of the bearings and gears at the top difficult. To lubricate the top bearings, the reducer typically uses a forced lubrication system or has an oil replenishment tank. Due to the reducer's compact design and weak heat dissipation capacity, coupled with its small speed ratio, high speed, and large heat generation, lubrication and seal failures are easily caused. This invention uses an external rotor direct-drive motor, eliminating the intermediate energy transmission of the reducer, thus improving system transmission efficiency and eliminating reducer lubrication and sealing failures.

[0022] Traditional mixers typically use a drive mechanism consisting of a three-phase asynchronous motor, a reducer, a coupling, and an agitator. This mechanism is usually mechanically fixed to the top of the mixing tank, preventing the top from being opened. Cleaning the interior requires disassembling these components, resulting in wasted time during maintenance. In contrast, the drive mechanism of this invention is located at the bottom of the mixing tank. The upper part of the tank has no mechanical drive or transmission devices, allowing for complete opening of the top cover. Furthermore, the mixing tank consists of inner and outer tanks, with the inner tank easily lifted from the top for convenient cleaning and inspection of the interior.

[0023] Traditional mixers typically use a rotating impeller on the axis of the mixing tank. The impeller drives the liquid inside the tank to rotate, generating centrifugal force, which then flows back to the center to achieve mixing. This method causes liquids of different densities to flow in fixed stratification, resulting in uneven mixing and low efficiency. The impeller of this invention is located on one side of the inner wall of the mixing tank. As the impeller blades rotate, they circulate the liquid inside the tank through guide plates and channels back to the bottom of the tank, allowing liquids of different viscosities and densities to be fully mixed, thus improving mixing efficiency.

[0024] In the pharmaceutical and chemical industries, the liquids inside mixers are often corrosive, which can damage the seal at the mixing blade shaft. Alternatively, during mixing, centrifugal force can throw the liquid against the inner wall of the tank, and at high speeds, the liquid can easily splash outside the tank, causing environmental pollution or corrosion to external equipment. This invention addresses this issue by using magnetically driven mixing blades that direct the mixing towards the inside of the tank. Furthermore, the outer tank is equipped with a guide plate, and the inner tank has a guide groove. The upper part of the tank lacks any holes caused by the drive structure, allowing for a complete seal and preventing liquid leakage from the mixing tank.

[0025] Traditional mixers use three-phase asynchronous motors that cannot be speed-adjusted, making it impossible to adjust the speed according to the viscosity and volume of the liquid in the mixing tank, resulting in energy waste. The permanent magnet direct-drive motor used in this invention, equipped with a frequency converter, can achieve speed adjustment. The mixing speed can be adjusted according to working conditions. When the liquid in the mixing tank has high viscosity and large volume, the speed of the permanent magnet direct-drive motor increases, and simultaneously the lower cylinder rises, causing the magnets to move closer to the outer tank's iron ring, increasing the repulsive force and the levitation force of the mixing blades. This eliminates mechanical friction between the mixing blades and the tank body, saving energy.

[0026] Traditional mixers use three-phase asynchronous motors that generate high starting current and torque when the agitator starts, causing impact wear on gears and couplings in the transmission chain. This invention uses a dedicated frequency converter for soft starting, with a customizable starting time, reducing starting current, minimizing impact on the power grid, and protecting the equipment. It also offers excellent heavy-load starting performance. The frequency converter-controlled permanent magnet direct-drive motor provides high-torque soft starting, minimizing dynamic tension impact during startup, significantly reducing the impact on electrical and mechanical equipment. Compared to traditional drive methods, it offers a higher dynamic safety factor under the same operating conditions, effectively improving the overall operational safety of the equipment.

[0027] Compared with existing technologies, this invention uses magnetic force to guide the stirring, while the blades are suspended under the action of magnetism, resulting in higher efficiency. It eliminates all other transmission chain devices, increases the stability of the drive system, and achieves stepless speed adjustment. Simultaneously, during the stirring process, the liquid in the stirring tank flows from the outside to the inside and then back to the outside, passing through multiple guide channels, ensuring thorough mixing and improving stirring efficiency and uniformity. Attached Figure Description

[0028] Figure 1 This is a cross-sectional schematic diagram of a permanent magnet driven stirring device according to an embodiment of the present invention.

[0029] Figure 2 This is a top view schematic diagram of the permanent magnet driven stirring device according to an embodiment of the present invention.

[0030] Figure 3 This is a top view of the bottom internal structure of the permanent magnet driven stirring device according to an embodiment of the present invention.

[0031] Figure 4 This is a schematic diagram of the magnetic circuit of the permanent magnet driven stirring device according to an embodiment of the present invention.

[0032] Figure 5 This is a three-dimensional schematic diagram of the magnetic levitation stirrer of the permanent magnet driven stirring device according to an embodiment of the present invention.

[0033] Figure 6 This is a three-dimensional schematic diagram of the components of the permanent magnet driven stirring device according to an embodiment of the present invention, consisting of a rotating disk and a magnetic drive head.

[0034] Figure 7 This is a three-dimensional schematic diagram of the rotating frame of the permanent magnet driven stirring device according to an embodiment of the present invention.

[0035] Figure 8 This is a three-dimensional schematic diagram of the magnetic drive head of the permanent magnet driven stirring device according to an embodiment of the present invention.

[0036] Figure 9 This is a three-dimensional schematic diagram of the components of the permanent magnet driven stirring device according to an embodiment of the present invention, consisting of a stirring tank, a rotating disk, and a magnetic drive head.

[0037] Figure 10 for Figure 1 A partially enlarged view, used for illustrative purposes. Figure 1 The mounting structure of the magnet and the magnet ring shown in the embodiment.

[0038] Summary of reference numerals in the attached drawings: 1. Mixing tank; 11. Mixing tank cover; 12. Inner tank; 13. Outer tank; 14. Magnetic steel sealing cover; 131. Cylinder bracket; 132. Suspension adjustment magnet; 133. Adjustment cylinder; 134. First guide channel; 135. Second guide channel; 136. Guide plate; 137. Third guide channel; 2. Mixer frame; 3. Mixing drive component; 31. Permanent magnet direct drive motor; 32. Drive connection flange; 33. Rotary disc; 34. Magnetic drive head; 341. Yoke; 342. Magnetic steel limit block; 343. Reinforcing plate; 344. Inclined magnet; 345. Horizontal magnet; 446. Magnetic suspension mixer; 41. Mixing blade; 42. Blade support plate; 43. Outer arc repulsive magnet; 44. Inner arc repulsive magnet; 45. Magnet ring; 46. Blade iron ring; 47. Sealing ring. Detailed Implementation

[0039] In the following description, embodiments of the permanent magnet driven stirring apparatus of the present invention will be described with reference to the accompanying drawings.

[0040] The embodiments described herein are specific implementations of the present invention, used to illustrate the technical concept of the invention, and are illustrative and exemplary, and should not be construed as limiting the embodiments or scope of the present invention. In addition to the embodiments described herein, those skilled in the art can employ other obvious technical solutions based on the content disclosed in the claims and specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein.

[0041] Furthermore, please note that the specific embodiments described herein are specific implementations of the technical solutions described in the claims. As mentioned above, the technical concept of the present invention is explained by the embodiments. In other words, the scope of protection of certain technical solutions described in the claims is greater than these specific embodiments.

[0042] The accompanying drawings in this specification are schematic diagrams used to illustrate the concept of the invention and to schematically show the shapes of the various parts and their interrelationships. Please note that, in order to clearly show the structure of the various components in the embodiments of the invention, the drawings are not necessarily drawn to the same scale.

[0043] Figure 1 This is a cross-sectional schematic diagram of the permanent magnet driven stirring device according to an embodiment of the present invention. Figure 2 This is a top view schematic diagram of the permanent magnet driven stirring device according to an embodiment of the present invention. Figure 3This is a top view of the bottom internal structure of the permanent magnet driven stirring device according to an embodiment of the present invention.

[0044] An embodiment of the present invention provides a permanent magnet driven stirring device, comprising: a stirring tank 1, a stirring frame 2, a stirring drive component 3, a magnetic levitation stirrer 4, and a drive control system.

[0045] The mixing tank 1 is used to hold and mix liquids. The mixing tank 1 consists of an inner tank 12, an outer tank 13, and a mixing tank cover 11. The inner and outer tanks are completely separable; once opened, the interior of the outer tank is easy to clean and maintain. The bottom of the mixing tank 1 is equipped with a magnetic ring 45, an inner arc repulsive magnet 44, and an outer arc repulsive magnet 43. These are completely covered by a magnetic sealing cover 14, providing buoyancy for the magnetic levitation stirrer 4. A cylinder support 131 is located at the lower part of the outer tank 13 to support the adjusting cylinder 133, which pushes the suspension adjusting magnet 132. The closer the suspension adjusting magnet 132 is to the magnetic ring 45 of the outer tank, the greater the repulsive force, resulting in greater levitation force for the magnetic levitation stirrer 4 and allowing for higher mixing speeds.

[0046] In this example, there are four magnetic steel sealing cover plates 14, which are annular structures with through holes evenly distributed on the inner and outer rings. Through the through holes on the inner and outer rings of the magnetic steel sealing cover plates 14, they are fixed to the corresponding threaded holes of the inner tank 12, outer tank 13, and magnetic levitation stirrer 4, respectively, pressing the sealing rings 47 of the mating surfaces together.

[0047] See Figure 1 , 2 3 and 9, the internal devices of the mixing tank 1 include: a guide plate 136, a first guide channel 134, a second guide channel 135, and a third guide channel 137. The liquid inside the mixing tank 1 is stirred and flows sequentially through the aforementioned devices under the combined action of the stirring blades 41 and centrifugal force, and then flows back, repeating this cycle repeatedly to achieve thorough mixing and fusion, thus achieving the purpose of stirring and fusion. See also... Figure 9 In the embodiment shown, the first guide groove 134 and the second guide groove 135 are elongated holes, while the third guide groove 137 is a circular hole.

[0048] The stirring drive component 3 generates a rotating magnetic field, thereby driving the magnetic levitation stirrer 4. The stirring blades 41 are made of a material with high magnetic permeability, preferably electromagnetic pure iron or low carbon steel, but high-permeability stainless steel, such as 430, can also be used. The stirring blades 41 are fixed on the blade support plate 42 to form the magnetic levitation stirrer 4. The stirring blades 41 can conduct the upper and lower magnetic circuits of the stirring drive component 3, such as... Figure 4 As shown, a strong attractive force is generated, which drives the magnetic levitation stirrer 4 to generate synchronous speed.

[0049] The stirring drive component 3 includes: a permanent magnet direct drive motor 31, a drive connection flange 32, a rotating disk 33, and a magnetic drive head 34; the permanent magnet direct drive motor 31 can provide different stirring speeds under the action of the drive control system.

[0050] The permanent magnet direct drive motor 31 is connected to the lower end face of the drive connection flange 32 via a shaft extension and keyway. The upper end face of the drive connection flange 32 is fastened to the rotating disk 33 by bolts on its circumference. In this way, the power of the permanent magnet direct drive motor 31 drives the magnetic drive head 34 on the rotating disk 33 to rotate. The drive connection flange 32 consists of upper and lower end faces and a ring of stiffening plates connecting them. The lower end face has a bushing at its center for connecting the motor shaft, and the outer circle of the upper end face has a ring of evenly distributed connecting holes for connecting and fixing to the rotating disk 33.

[0051] The magnetic drive head 34 includes: a yoke 341, a magnetic steel limiting block 342, a reinforcing plate 343, an oblique magnet 344, and a transverse magnet 345. The oblique magnet 344 provides a magnetic focusing effect, preventing the magnetic field from dissipating and enhancing the magnetic force; the yoke 341, oblique magnet 344, transverse magnet 345, and stirring blade 41 form a complete circulating magnetic circuit, making full use of the magnetic material. The solution provided by this invention uses six sets of magnetic drive heads 34. If the mixer is used for highly viscous substances, the stirring torque can be increased by increasing the number of magnetic drive heads 34.

[0052] The magnetic drive head 34 is fixed to the base on the upper surface of the rotating disk 33 by screws. The number can be the same as the stirring blades. When the viscosity of the stirring liquid is low or the stirring speed is low, the number can be halved. As shown in the figure, there are 12 blades and 6 sets of magnetic drive heads 34. The matching number of stirring blades 41 and magnetic drive heads 34 can also be adjusted according to different stirring liquids and stirring speeds.

[0053] The two poles of the magnetic drive head 34 are respectively focused magnetic circuit structures with opposite orientations, which can effectively reduce the escaping magnetic field, concentrate the magnetic lines of force, increase the attraction to the stirring blades 41, and improve the utilization rate of the magnetic material. For the specific magnetic orientation of the magnetic drive head 34, please refer to [link to relevant documentation]. Figure 1 The arrows indicate that the N-pole transverse magnetic block is oriented towards the stirring blade 41, and the two oblique magnetic blocks on both sides are oriented at a 30° angle inwards. The S-pole transverse magnetic block is oriented towards the yoke 341, and the two oblique magnetic blocks on both sides are oriented at a 30° angle outwards.

[0054] The magnetic levitation stirrer 4 includes: stirring blades 41, blade support plate 42, outer arc repulsive magnet 43, inner arc repulsive magnet 44, and magnet ring 45. The magnetic levitation stirrer 4 is sandwiched between the outer arc repulsive magnet 43, inner arc repulsive magnet 44, and magnet ring 45 at the bottom of the inner mixing tank 12 and the outer tank 13. Because there are focused magnetic fields of the same polarity at the top and bottom, and the magnetic drive head 34 provides a uniformly distributed attraction in the circumferential direction, it can levitate between the inner and outer tanks of the mixing tank without contact friction.

[0055] See especially Figure 10 The magnetic suspension stirrer 4 is mainly composed of a blade support plate 42. Two magnetic steel sealing cover plates 14 are connected to the inner side of the blade support plate 42 by screws. An inner arc repulsive magnet 44 in the inner ring and an outer arc repulsive magnet 43 in the outer ring are assembled in the inner layer of the two magnetic steel sealing cover plates 14. A magnet ring 45 is assembled in the gap between the inner arc repulsive magnet 44 and the outer arc repulsive magnet 43. The inner and outer arc magnets are glued to the pit formed by the magnetic steel sealing cover plate 14, the blade iron ring 46, and the blade support plate 42 using anaerobic structural adhesive.

[0056] Three rings of magnets—inner arc repulsive magnet 44, outer arc repulsive magnet 43, and magnet ring 45—are located at the bottom of the inner tank, the bottom of the outer tank, and on the magnetic levitation stirrer 4, respectively. The magnets are oriented as follows: Figure 1 As shown, the N poles of the aforementioned magnets all point to the magnetic ring 45 of their respective layers. The volume of the iron ring is approximately 1 / 3 to 1 / 2 of the total volume of the magnets, ensuring their magnetic saturation strength and thus improving the repulsive force between the magnetic levitation stirrer 4 and the inner and outer tanks 12 and 13. The magnetic ring 45 can be made as a single piece or evenly segmented. The maximum width of the inner arc repulsive magnet 44 and the outer arc repulsive magnet 43 is ensured to be less than 100 mm to improve the manufacturability of the magnets.

[0057] The drive connection flange 32 has an annular flange on top, with evenly distributed through holes on the outer ring for connecting the rotating disk 33. A keyway-equipped bushing is located at the center of the lower disk for connecting the shaft extension of the permanent magnet direct drive motor 31. The upper annular flange and the lower disk are connected by evenly distributed stiffening plates along the central circumference.

[0058] The permanent magnet direct drive motor used in this embodiment is equipped with a frequency converter to achieve speed regulation. The stirring speed can be adjusted according to the working conditions. When the liquid in the stirring tank has high viscosity and large volume, the speed of the permanent magnet direct drive motor increases. At the same time, the lower cylinder is raised, which drives the magnet to come closer to the iron ring of the outer tank, thereby increasing the repulsive force and the suspension force of the stirring blades. There is no mechanical friction between the stirring blades and the tank body, which saves energy.

[0059] This embodiment uses a dedicated frequency converter for soft starting, with a customizable start-up time, reducing starting current, minimizing impact on the power grid, and protecting the equipment. It offers excellent heavy-load starting performance, employing a frequency converter to control the permanent magnet direct drive motor for high-torque soft starting. The dynamic tension impact during startup is minimal, significantly reducing the impact on electrical and mechanical equipment. Compared to traditional drive methods, under the same operating conditions, it boasts a higher dynamic safety factor, effectively improving the overall operational safety of the equipment.

[0060] This invention employs magnetically guided stirring, with the stirring blades suspended under the influence of magnetism, resulting in higher efficiency. It eliminates all other transmission chain devices, increasing the stability of the drive system and enabling stepless speed adjustment. Simultaneously, during stirring, the liquid inside the mixing tank flows from the outside in and then back out, passing through multiple guide channels, ensuring thorough mixing and improving stirring efficiency and uniformity.

[0061] The embodiments of the permanent magnet driven stirring device of the present invention have been described above, with the aim of explaining the spirit of the present invention. Please note that those skilled in the art can modify and combine the features of the above embodiments without departing from the spirit of the present invention; therefore, the present invention is not limited to the above embodiments. Specific features of the permanent magnet driven stirring device, such as shape, size, and position, can be specifically designed based on the functions of the features disclosed above, and these designs are all achievable by those skilled in the art. Furthermore, the technical features disclosed above are not limited to combinations with other features; those skilled in the art can also make other combinations between the technical features according to the purpose of the invention, to achieve the purpose of the present invention.

Claims

1. A permanent magnet driven stirring device, characterized in that, include: Mixing tank, mixer frame, mixing drive components, magnetic levitation mixer, and drive control system; The mixing tank includes an inner tank and an outer tank, which can be completely separated, and the magnetic suspension stirrer is rotatably clamped in the gap between the bottom of the inner tank and the bottom of the outer tank; Magnets are installed at the bottom of both the inner and outer tanks, and are completely covered by a sealing cover to provide buoyancy for the magnetic suspension stirrer. The magnetic levitation stirrer includes stirring blades, blade support plates, and magnets. The magnets at the bottom of the inner tank and the bottom of the outer tank both have a focusing magnetic field with the same polarity as the focusing magnetic field of the magnets of the magnetic levitation stirrer. The stirring drive component includes a permanent magnet direct drive motor, a drive connection flange, a rotating disk, and a magnetic drive head; The permanent magnet direct drive motor is connected to the lower end face of the drive connection flange via a shaft extension, and the upper end face of the drive connection flange is fastened to the rotating disk. Thus, the permanent magnet direct drive motor drives the magnetic drive heads evenly distributed on the rotating disk to rotate. The magnetic drive head includes a yoke, an oblique magnet, and a transverse magnet. The oblique magnet provides a magnetic focusing effect, prevents the magnetic field from dissipating, and enhances the magnetic force. The yoke, the oblique magnet, the transverse magnet, and the stirring blade form a complete circulating magnetic circuit, thereby providing a uniformly distributed attractive force to the magnetic levitation stirrer in the circumferential direction, driving the magnetic levitation stirrer to generate a synchronous rotation speed.

2. The permanent magnet driven stirring device according to claim 1, characterized in that, The permanent magnet driven stirring device also includes an adjusting cylinder, a cylinder support, and a suspension adjusting magnet. The cylinder support is located at the lower part of the outer tank of the stirring tank and is used to support the adjusting cylinder to push the suspension adjusting magnet. The closer the suspension adjusting magnet is to the magnet at the bottom of the outer tank, the greater the repulsive force it provides, and the greater the levitation force of the magnetic levitation stirrer.

3. The permanent magnet driven stirring device according to claim 1, characterized in that, The magnetic drive head includes two poles arranged vertically, namely an N pole and an S pole. Each pole includes a yoke, two oblique magnets, and a transverse magnet sandwiched between the two oblique magnets. The transverse magnet of the N pole is oriented towards the stirring blade, and the oblique magnets on both sides are oriented obliquely inward. The transverse magnet of the S pole is oriented towards the yoke, and the oblique magnets on both sides are oriented obliquely outward. The stirring blades connect the upper and lower magnetic circuits of the stirring drive component.

4. The permanent magnet driven stirring device according to claim 1, characterized in that, Both the magnet at the bottom of the inner can and the magnet at the bottom of the outer can include a magnet ring, an inner arc repulsive magnet, and an outer arc repulsive magnet. The magnet ring is assembled in the gap between the inner arc repulsive magnet and the outer arc repulsive magnet. The magnet of the magnetic levitation stirrer includes an outer arc repulsive magnet, an inner arc repulsive magnet, and a magnet ring. The outer arc repulsive magnet, the inner arc repulsive magnet, and the magnet ring of the magnetic levitation stirrer are arranged on the same plane of the blade support plate, and the magnet ring of the magnetic levitation stirrer is assembled in the gap between the outer arc repulsive magnet and the inner arc repulsive magnet.

5. The permanent magnet driven stirring device according to claim 4, characterized in that, The magnetic rings, inner arc repulsive magnets, and outer arc repulsive magnets at the bottom of the inner tank and the bottom of the outer tank are all completely covered by magnetic sealing covers at the bottom of the inner tank and the bottom of the outer tank. The magnetic levitation stirrer also includes a blade ring located at the center of the blade support plate. The outer and inner arc repulsive magnets of the magnetic levitation stirrer are bonded to a recess formed by the magnetic steel sealing cover plate, the blade ring, and the blade support plate using anaerobic structural adhesive. The magnetic steel sealing cover plate at the bottom of the inner tank, the magnetic steel sealing cover plate at the bottom of the outer tank, and the magnetic steel sealing cover plate of the magnetic levitation stirrer are all annular structures with through holes evenly distributed on the inner and outer rings. They are fixed to the corresponding threaded holes of the inner tank, the outer tank, and the magnetic levitation stirrer, respectively, to press the sealing rings of the mating surfaces together.

6. The permanent magnet driven stirring device according to claim 5, characterized in that, The inner tank has a first guide channel evenly distributed on its peripheral wall, a second guide channel evenly distributed on its bottom wall, and a third guide channel located at the center of the bottom wall. The first and second guide channels are elongated holes, while the third guide channel is a circular hole. At least one annular guide plate is provided on the peripheral wall of the outer tank. Under the combined action of the stirring blades and centrifugal force, the liquid inside the mixing tank is stirred and flows sequentially through the first guide channel, the second guide channel, the third guide channel, and the guide plate, and then flows back, thus repeating the cycle.

7. The permanent magnet driven stirring device according to claim 1, characterized in that, The number of stirring blades is 12, and the number of magnetic drive heads is 6.

8. The permanent magnet driven stirring device according to claim 4, characterized in that, The N poles of both the inner and outer arc repulsive magnets point towards the matching magnetic ring. The volume of the magnetic ring is approximately 1 / 3 to 1 / 2 of the total volume of the matching magnets to ensure its magnetic saturation strength, thereby increasing the repulsive force between the magnetic levitation stirrer and the inner and outer tanks.

9. The permanent magnet driven stirring device according to claim 4, characterized in that, The magnet ring can be made as a single piece or divided into evenly spaced segments; and The maximum width of both the inner arc repulsive magnet and the outer arc repulsive magnet is guaranteed to be less than 100mm.

10. The permanent magnet driven stirring device according to any one of claims 1-9, characterized in that, The drive connection flange includes a lower disc, an upper annular flange, and stiffening plates for connecting the disc and the annular flange. The stiffening plates are perpendicular to the disc and the annular flange and are evenly distributed along the circumference of the disc and the annular flange. The outer ring of the annular flange has evenly distributed through holes for connecting the rotating disk, and the center of the disk is provided with a keyway bushing for connecting the shaft extension of the permanent magnet direct drive motor.

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