Active magnetic levitation belt conveyor and method

Abstract

An active magnetic levitation belt conveyor device and method belong to the field of magnetic levitation belt conveyor technology. The device includes a composite conveyor belt, an integrated functional fixed base layer, a Halbach support array, a linear motor drive stator, an E-type damping electromagnet, a Hall pressure sensor array, and a support frame structure. A sulfurized magnet array is attached to the bottom surface of the composite conveyor belt as a magnetic induction actuator; the Halbach support array is embedded in the base layer to provide contactless vertical levitation support; the linear motor drive stator generates a traveling wave magnetic field to provide propulsion; the E-type damping electromagnet realizes dynamic air gap compensation and local deformation adjustment; and the Hall pressure sensor array monitors the changes in magnetic induction intensity caused by belt deformation in real time. This invention, through active magnetic levitation technology, solves the problems of high mechanical friction loss, poor load adaptability, and high maintenance costs of traditional belt conveyors, achieving contactless levitation operation, dynamic air gap compensation, and precise control of the belt, with advantages such as high operating efficiency, low energy consumption, and simple maintenance.

Description

Technical Field

[0001] This invention belongs to the field of magnetic levitation belt conveyor technology, and specifically relates to an active magnetic levitation belt conveyor device and method. Background Technology

[0002] Traditional belt conveyors generally employ a roller-supported structure, where the conveyor belt is supported by idler rollers, and material transport is achieved through the friction between the drive rollers and the belt. However, this traditional structure presents the following major technical problems in practical applications: First, traditional roller-supported belt conveyors suffer from significant mechanical friction losses. The continuous rolling friction between the idler rollers and the belt leads to accelerated belt wear, shortens its service life, and generates a large amount of heat and noise, resulting in low energy efficiency. Mechanical friction losses can account for 25%-30% of total energy consumption.

[0003] Secondly, traditional belt conveyors have poor adaptability to varying load conditions. When material distribution is uneven or there are sudden changes in load, the belt is prone to downward deformation, leading to unstable conveying and even malfunctions such as belt misalignment and slippage. Existing mechanical support structures cannot achieve dynamic adjustment, making it difficult to ensure stable operation of the belt under different load conditions.

[0004] Secondly, traditional belt conveyors require significant maintenance and are costly. Idler rollers, being wear parts, need to be replaced regularly, and roller bearings require regular lubrication and maintenance. Under harsh operating conditions, the maintenance frequency is even higher, severely impacting production continuity.

[0005] Although magnetic levitation belt conveyor technology has emerged in recent years, existing magnetic levitation belt conveyor devices mostly adopt passive levitation structures with fixed levitation gaps, which cannot be dynamically adjusted according to load changes. This results in poor levitation stability under heavy load conditions and significant energy waste under light load conditions. At the same time, existing technologies lack effective belt deformation sensing and active compensation mechanisms, making it difficult to achieve precise control of the belt's operating status.

[0006] Therefore, there is an urgent need to develop an active magnetic levitation belt conveyor that can achieve dynamic suspension adjustment, active deformation compensation, and high-efficiency energy-saving operation. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide an active magnetic levitation belt conveyor device and method. The present invention achieves non-contact magnetic levitation support of the belt through the Halbach support array, which completely eliminates the mechanical friction between the traditional idler roller and the belt, reduces the friction loss of the conveying system, and reduces the overall energy consumption compared with the traditional belt conveyor, resulting in significant energy saving effect.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: An active magnetic levitation belt conveyor includes a composite conveyor belt, an integrated functional fixed base layer, a Halbach support array, a linear motor drive stator, an E-type damping electromagnet, a Hall pressure sensor array, and a support frame structure. The composite conveyor belt is 3mm thick, and a discrete array of sulfurized magnets is uniformly attached to the bottom surface of the composite conveyor belt as a magnetic induction actuator. The integrated functional fixed base layer is located below the composite conveyor belt. It is a flat plate structure made of non-magnetic material and is rigidly fixed to the frame. It serves as the overall support and functional integrated chassis of the device. Three rows of magnetic power composite units are arranged in parallel along the longitudinal direction on the surface of the integrated functional fixed base layer. The Halbach support array is embedded in an integrated functional fixed base layer to provide contactless vertical suspension support. The linear motor drive stator is arranged in the integrated functional fixed base layer along the conveying direction, and provides continuous forward propulsion by generating a translational traveling wave magnetic field; The E-type damping electromagnet is installed in the integrated functional fixed base layer to realize dynamic air gap compensation and local deformation adjustment during belt operation. A Hall pressure sensor array is uniformly arranged on the lower surface of the composite conveyor belt to monitor the change signal of magnetic induction intensity caused by belt deformation in real time. The support frame structure is located below the integrated functional fixed base layer and is used to support the weight of the integrated functional fixed base layer and all components above it, and to transfer the load to the ground.

[0009] As a preferred embodiment, the Halbach support array consists of multiple square permanent magnet blocks arranged in a periodic rotational pattern along the belt movement direction at magnetization vector directions of 0°, 90°, 180°, and 270°. This arrangement causes the magnetic lines of force to be superimposed and enhanced on the side facing the composite conveyor belt, thereby providing static levitation support for the composite conveyor belt and load without increasing additional excitation energy consumption.

[0010] As a preferred embodiment, the linear motor drive stator adopts a slotless structure, and the coil frequency of the linear motor drive stator is adjustable to achieve stepless speed regulation of the composite conveyor belt; the traveling wave magnetic field generated by the linear motor drive stator directly acts on the sulfurized magnet array at the bottom of the composite conveyor belt to achieve power coupling transmission without sliding friction.

[0011] As a preferred embodiment, the E-type damping electromagnet includes an "E"-shaped magnetic core and an excitation coil wound on the central tooth; by adjusting the magnitude of the excitation current, the magnetic tension between the central tooth and the magnet at the bottom of the composite conveyor belt is changed in real time, thereby compensating for the belt deflection caused by the material load, with a response time of less than 10ms.

[0012] As a preferred embodiment, the Hall pressure sensor array is embedded in the surface of the composite conveyor belt in a matrix manner to sense the change in magnetic flux caused by the magnet below the composite conveyor belt approaching or moving away in real time; the Hall pressure sensor array is connected to the control system and is used to convert physical deformation displacement into an electrical signal and feed it back to the E-type damping electromagnet actuator.

[0013] As a preferred embodiment, the length and width of each independently controlled magnetic power composite unit module are between 30mm and 40mm, and the total thickness is between 15mm and 20mm; the left, middle and right columns of units are provided with ultra-thin high-density ceramic magnetic shielding sheets with a thickness of 1.5mm to ensure that each column of magnetic circuits operates independently and does not interfere with each other.

[0014] As a preferred embodiment, the vulcanized magnet array is composited with a rubber substrate using a discrete particle arrangement process, so that the magnets can undergo elastic deformation synchronously with the composite conveyor belt when subjected to local flexing due to material pressure, without falling off or abrupt magnetic changes.

[0015] As a preferred embodiment, the support frame structure is provided with a set of rollers at the beginning and end of the conveyor line to support and tighten the composite conveyor belt. The rollers are connected to the integrated functional fixed base layer through bearing seats and provide rigid support.

[0016] A conveying adjustment method for an active magnetic levitation belt conveyor includes the following steps: S1. Initial Suspension: The Halbach support array generates a single-sided enhanced magnetic field, enabling the 3mm thick composite conveyor belt to overcome its own weight and enter a stable suspension state; S2. Uniform speed drive: The linear motor drives the stator to generate a controlled traveling wave magnetic field, which drags the composite conveyor belt to run smoothly in a predetermined direction; S3. Deformation sensing: Hall pressure sensor array captures the enhanced magnetic signal fluctuations in the material landing area caused by the reduction of the air gap; S4. Active Lifting: The control system commands the E-type damping electromagnet at the corresponding position to instantly increase the current, generating a compensating magnetic force to counteract the weight of the material and restore the rated air gap; S5. Collaborative Correction: By independently adjusting the force on the left, middle, and right columns of units, the belt tilting or offset caused by uneven material distribution is corrected.

[0017] In step S3, the Hall pressure sensing array monitors the change in magnetic induction intensity in real time at a sampling frequency of over 100Hz. When the detected magnetic signal fluctuation exceeds the preset threshold, the compensation action of the E-type damping electromagnet is immediately triggered. In step S4, the current adjustment range of the E-type damping electromagnet is 0-5A, and the adjustment accuracy reaches 0.1A, ensuring precise control of air gap compensation.

[0018] The present invention can achieve the following beneficial effects: 1. This invention achieves contactless magnetic levitation support for the belt through the Halbach support array, completely eliminating the mechanical friction between the traditional idler roller and the belt, reducing friction loss of the conveying system, reducing overall energy consumption compared to traditional belt conveyors, and achieving significant energy-saving effects.

[0019] 2. The E-type damping electromagnet of this invention works in conjunction with the Hall pressure sensor array to sense belt deformation in real time and perform dynamic air gap compensation, effectively solving problems such as belt deflection and deviation in traditional conveyors when the load changes, and ensuring stable operation under different working conditions.

[0020] 3. This invention uses non-contact suspension technology, which eliminates the wear problem of vulnerable parts such as idlers and bearings, and significantly improves the reliability of the equipment and the continuity of production.

[0021] 4. The linear motor drive stator of this invention provides precise traveling wave magnetic field driving force, and combined with active suspension control, it realizes precise control of belt speed and position.

[0022] 5. The contactless operation mode of this invention effectively avoids mechanical wear of the belt, extends the belt's service life, reduces dust generation, and improves the working environment.

[0023] 6. The Hall pressure sensor array integrated in this invention enables real-time monitoring and intelligent diagnosis of belt operating status, providing data support for predictive maintenance and improving the intelligent management level of the equipment.

[0024] 7. This device is suitable for material conveying in various industrial fields such as mining, ports, power, metallurgy, and chemical industry. It is especially suitable for conveying scenarios with high speed, heavy load, and high precision requirements, and has good prospects for promotion and application. Attached Figure Description

[0025] The present invention will be further described below with reference to the accompanying drawings and embodiments: Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is an isometric view of the arrangement of permanent magnets on the bottom surface of the belt in this invention; Figure 3 This is a diagram showing the internal module layout of the track in this invention; Figure 4 This is a magnified detail view of a single functional unit of the present invention. Detailed Implementation

[0026] Preferred solutions include Figures 1 to 4As shown, an active magnetic levitation belt conveyor can be applied to large-scale logistics sorting centers. The active magnetic levitation belt conveyor includes a frame, a conveyor belt, a magnetic levitation support unit, a drive unit, and a control system. The frame is welded from Q345B steel, with a total length of 15 meters, a width of 1.2 meters, and a height of 0.8 meters. The surface is hot-dip galvanized, achieving a corrosion resistance level of C4. The conveyor belt is a steel wire rope core rubber belt, 12mm thick, 1000mm wide, with a tensile strength of 2000N / mm, and an anti-slip pattern on the surface, suitable for conveying at inclination angles of 0-30°. The magnetic levitation support unit consists of 24 sets of electromagnet arrays, evenly arranged along the length of the frame at 0.6-meter intervals. Each set of electromagnets includes a U-shaped iron core and double coil windings, operating at 24VDC, with a maximum levitation force of 500N.

[0027] The drive unit includes a linear motor drive stator, a reducer, and a drive roller. The linear motor drive stator has a power of 15kW and a rated speed of 1480rpm. It is connected to the planetary gear reducer via a coupling, with a reduction ratio of 25:1. The drive roller has a diameter of 400mm and is covered with polyurethane material, with a friction coefficient of 0.8. The control system includes a PLC controller, a sensor array, and a human-machine interface. The PLC controller is a Siemens S7-1200 series, and the sensor array includes position, pressure, and speed sensors. Under no-load conditions, the conveying speed is adjustable from 0-3m / s, the suspension gap is adjustable from 2-5mm, and power consumption is reduced by 35% compared to traditional roller-supported systems.

[0028] The selection and configuration of the drive unit underwent precise calculations and repeated verification. The choice of the 15kW linear motor drive stator power was based on a maximum load of 1.5 tons and a speed requirement of 3m / s, with optimal matching parameters determined through theoretical calculations and actual testing. Compared to ordinary gear reducers, planetary gear reducers offer higher transmission efficiency and smaller size, making them particularly suitable for space-constrained industrial environments. The drive roller surface is coated with polyurethane instead of rubber because polyurethane exhibits better wear resistance and anti-aging properties during long-term operation. A friction coefficient of 0.8, verified through laboratory testing, ensures stable transmission performance under various humidity conditions, preventing belt slippage.

[0029] The magnetic levitation support unit employs Halbach support arrays, each equipped with an independent current controller. Pressure sensors monitor the levitation gap in real time. When a gap change exceeds ±0.5mm, the current controller automatically adjusts the coil current to maintain a stable levitation gap. Under varying load conditions, the system response time is less than 50ms, and levitation gap fluctuations are controlled within ±0.3mm. The Halbach support array's arrangement density is optimized; a 0.6-meter spacing ensures sufficient support rigidity while avoiding electromagnetic interference and reducing system costs. The Halbach support array utilizes a special magnetic circuit design, effectively concentrating magnetic lines of force, improving magnetic circuit efficiency, and enhancing the system's anti-interference capability and stability.

[0030] The implementation of the Halbach support array (also known as the Halbach array) relies on high-precision sensors and fast-response current controllers. Strain gauge pressure sensors are chosen instead of piezoelectric sensors because strain gauge sensors offer better stability and accuracy in static and quasi-static measurements, making them particularly suitable for applications requiring long-term stable monitoring, such as suspension gaps. A system response time of 50ms was determined through extensive experimentation. This time constant ensures system stability while enabling rapid response to load changes and preventing belt vibration. The arrangement density of the Halbach support arrays is optimized to account for the superposition effect of suspension forces. Finite element analysis revealed that when the spacing is less than 0.5 meters, the magnetic lines of force between adjacent Halbach support arrays interfere with each other, leading to decreased efficiency; when the spacing is greater than 0.7 meters, the sag in the middle of the belt exceeds the allowable range. Therefore, 0.6 meters is the optimal spacing.

[0031] The specific structure and function of each component in this device are as follows: Composite conveyor belt 1: with a thickness of 3mm, and a discretely distributed array of sulfurized magnets 11 uniformly attached to its bottom surface as a magnetic induction actuator; Integrated functional fixing base layer 2: Located below the belt 1, it is a flat plate structure made of non-magnetic aluminum alloy or stainless steel, rigidly fixed to the frame. As the overall support and functional integration chassis of the device, its surface has three rows of magnetic power composite units arranged in parallel along the longitudinal direction (left, middle, and right). Halbach support array 3: embedded in the integrated functional fixed base layer 2, for providing contactless vertical suspension support; Linear motor drive stator 4: Arranged in the base layer along the conveying direction, it provides continuous forward propulsion by generating a traveling wave magnetic field that translates; Type E damping electromagnet 5: installed in the integrated functional fixed base layer 2, used to realize dynamic air gap compensation and local deformation adjustment during belt operation; Hall pressure sensor array 6: uniformly arranged on the lower surface of the composite conveyor belt 1, used to monitor the change signal of magnetic induction intensity caused by belt deformation in real time.

[0032] Support frame structure 7: Located below the integrated functional fixed base layer 2, it is used to bear the weight of the base layer and all components above it, and to transfer the load to the ground.

[0033] The Halbach support array 3 consists of multiple square permanent magnet blocks 31, which are periodically rotated and arranged along the belt movement direction in magnetization vector directions of 0°, 90°, 180°, and 270°. This arrangement causes the magnetic lines of force to be superimposed and enhanced on the side facing the belt 1, thereby providing static suspension support for the belt and load without increasing additional excitation energy consumption.

[0034] The linear motor drive stator 4 adopts a slotless structure, and its coil frequency is adjustable to achieve stepless speed regulation of belt 1; the traveling wave magnetic field generated by the stator 4 directly acts on the sulfurized magnet array 11 at the bottom of the belt to achieve power coupling transmission without sliding friction.

[0035] The E-type damping electromagnet 5 includes an "E"-shaped magnetic core and an excitation coil wound on the center tooth; by adjusting the magnitude of the excitation current, the magnetic tension between the center tooth and the magnet at the bottom of the belt is changed in real time, and displacement compensation is performed for the belt deflection caused by the material load, with a response time of less than 10ms.

[0036] The Hall pressure sensor array 6 is embedded in the surface of the composite conveyor belt 1 in a matrix manner to sense the change in magnetic flux caused by the magnet 11 below the belt approaching or moving away in real time; the sensor array 6 is connected to the control system and is used to convert physical deformation displacement into electrical signals and feed them back to the E-type damping electromagnet 5 actuator.

[0037] The dimensions of the micro-units are as follows: the length and width of each independently controlled magnetic power composite unit module are between 30mm and 40mm, and the total thickness is between 15mm and 20mm; the left, middle and right columns of units are provided with ultra-thin high-density ceramic magnetic shielding sheets 21 with a thickness of 1.5mm to ensure that each column of magnetic circuits operates independently and does not interfere with each other.

[0038] The vulcanized magnet array 11 is composited with a rubber substrate using a discrete particle arrangement process, so that the magnets can undergo elastic deformation synchronously with the belt 1 when it is subjected to local flexing due to material pressure, without falling off or abrupt magnetic change.

[0039] The support frame structure 7 is provided with a set of rollers 71 at the beginning and end of the conveyor line to support and tighten the composite conveyor belt. It is connected to the integrated functional fixed base layer 2 through the bearing seat 72 and provides rigid support.

[0040] The conveying and adjustment method of this device includes the following steps: S1. Initial levitation: The Halbach support array 3 generates a single-sided enhanced magnetic field, which enables the 3mm thick belt 1 to overcome its own weight and enter a stable levitation state; S2. Uniform speed drive: The linear motor drives the stator 4 to generate a controlled traveling wave magnetic field, which drags the belt 1 to run smoothly in the predetermined direction; S3. Deformation sensing: Hall pressure sensor array 6 captures the enhanced magnetic signal fluctuations in the material landing area caused by the reduction of the air gap; S4. Active lifting: The control system commands the E-type damping electromagnet 5 at the corresponding position to instantly increase the current, generating a compensating magnetic force to counteract the weight of the material and restore the rated air gap; S5. Collaborative Correction: By independently adjusting the force on the left, middle, and right columns of units, the belt tilting or offset caused by uneven material distribution is corrected.

[0041] The above embodiments are merely preferred technical solutions of the present invention and should not be considered as limitations on the present invention. The scope of protection of the present invention should be limited to the technical solutions described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. An active magnetic levitation belt conveyor characterized by comprising: It includes a composite conveyor belt (1), an integrated functional fixed base layer (2), a Halbach support array (3), a linear motor drive stator (4), an E-type damping electromagnet (5), a Hall pressure sensor array (6), and a support frame structure (7); wherein: Composite conveyor belt (1): The bottom surface is uniformly attached with a discretely distributed array of sulfurized magnets (11) as a magnetic induction actuator; Integrated functional fixed base layer (2): Located below the composite conveyor belt (1), it is a flat structure made of non-magnetic material. The surface of the integrated functional fixed base layer (2) has three rows of magnetic power composite units arranged in parallel along the longitudinal direction: left, middle and right. Halbach support array (3): embedded in integrated functional fixed base layer (2) to provide contactless vertical suspension support; Linear motor drive stator (4): Arranged in the integrated functional fixed base layer (2) along the conveying direction, it provides continuous forward propulsion by generating a translational traveling wave magnetic field; Type E damping electromagnet (5): installed in the integrated functional fixed base layer (2), used to realize dynamic air gap compensation and local deformation adjustment during belt operation; Hall pressure sensor array (6): uniformly arranged on the lower surface of composite conveyor belt (1) for real-time monitoring of magnetic induction intensity change signal caused by belt deformation; Support frame structure (7): Located below the integrated functional fixed base layer (2), used to support the integrated functional fixed base layer (2).

2. The active magnetic levitation belt conveyor device according to claim 1, characterized in that The Halbach support array (3) consists of multiple square permanent magnet blocks (31), which are periodically rotated and arranged along the belt movement direction according to the magnetization vector directions of 0°, 90°, 180° and 270°. This arrangement causes the magnetic lines of force to be superimposed and enhanced on the side facing the composite conveyor belt (1), thereby providing static levitation support for the composite conveyor belt (1) and the load without increasing additional excitation energy consumption.

3. The active magnetic levitation belt conveyor device according to claim 1, characterized in that: The linear motor drive stator (4) adopts a slotless structure. The coil frequency of the linear motor drive stator (4) is adjustable to achieve stepless speed regulation of the composite conveyor belt (1). The traveling wave magnetic field generated by the linear motor drive stator (4) directly acts on the sulfurized magnet array (11) at the bottom of the composite conveyor belt (1) to achieve power coupling transmission without sliding friction.

4. The active magnetic levitation belt conveyor device according to claim 1, characterized in that: The E-type damping electromagnet (5) includes an "E"-shaped magnetic core and an excitation coil wound on the center tooth; by adjusting the magnitude of the excitation current, the magnetic pull between the center tooth and the bottom magnet of the composite conveyor belt (1) is changed in real time, and displacement compensation is performed for the belt deflection caused by the material load, with a response time of less than 10ms.

5. The active magnetic levitation belt conveyor device according to claim 1, characterized in that: The Hall pressure sensor array (6) is embedded in the surface of the composite conveyor belt (1) in a matrix manner to sense the change in magnetic flux caused by the magnet (11) below the composite conveyor belt (1) approaching or moving away in real time; the Hall pressure sensor array (6) is connected to the control system to convert physical deformation displacement into electrical signals and feed them back to the E-type damping electromagnet (5) actuator.

6. The active magnetic levitation belt conveyor device according to claim 1, characterized in that: Each independently controlled magnetic power composite unit module has a length and width between 30mm and 40mm, and a total thickness between 15mm and 20mm. The left, middle and right columns of units are equipped with ultra-thin high-density ceramic magnetic shielding sheets (21) with a thickness of 1.5mm to ensure that each column of magnetic circuits operates independently and does not interfere with each other.

7. The active magnetic levitation belt conveyor device according to claim 1, characterized in that: The vulcanized magnet array (11) is composited with a rubber substrate using a discrete particle arrangement process, so that the magnets can undergo elastic deformation synchronously with the composite conveyor belt (1) when it is subjected to material pressure and local flexing, without falling off or abrupt magnetic change.

8. The active magnetic levitation belt conveyor device according to claim 1, characterized in that: The support frame structure (7) has a set of rollers (71) at the beginning and end of the conveyor line to support and tighten the composite conveyor belt (1). The rollers (71) are connected to the integrated functional fixed base layer (2) through the bearing seat (72) and provide rigid support.

9. A method of regulating the transport of a magnetic levitation belt conveyor according to any one of claims 1 to 8, characterized in that Includes the following steps: S1. Initial suspension: The Halbach support array (3) generates a single-sided enhanced magnetic field, which enables the 3mm thick composite conveyor belt (1) to overcome its own weight and enter a stable suspension state; S2. Uniform speed drive: The linear motor drives the stator (4) to generate a controlled traveling wave magnetic field, which drags the composite conveyor belt (1) to run smoothly in the predetermined direction; S3. Deformation sensing: Hall pressure sensor array (6) captures the magnetic signal enhancement fluctuation caused by the reduction of air gap in the material landing area; S4. Active lifting: The control system commands the E-type damping electromagnet (5) at the corresponding position to instantly increase the current, generate compensating magnetic force to counteract the weight of the material, and restore the rated air gap; S5. Collaborative Correction: By independently adjusting the force on the left, middle, and right columns of units, the belt tilting or offset caused by uneven material distribution is corrected.

10. The conveying and regulating method according to claim 9, characterized in that: In step S3, the Hall pressure sensor array (6) monitors the change in magnetic induction intensity in real time at a sampling frequency of more than 100Hz. When the magnetic signal fluctuation exceeds the preset threshold, the compensation action of the E-type damping electromagnet (5) is immediately triggered. In step S4, the current adjustment range of the E-type damping electromagnet (5) is 0-5A, and the adjustment accuracy reaches 0.1A, ensuring the precise control of air gap compensation.

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