CN111726038B - Lifting type magnetic suspension device - Google Patents

Lifting type magnetic suspension device Download PDF

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Publication number
CN111726038B
CN111726038B CN202010724539.7A CN202010724539A CN111726038B CN 111726038 B CN111726038 B CN 111726038B CN 202010724539 A CN202010724539 A CN 202010724539A CN 111726038 B CN111726038 B CN 111726038B
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magnetic field
magnetic
floater
stator
annular
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CN111726038A (en
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周赛君
张钊
张娅
原硕朋
周永学
展永霞
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Hebei Tengyun Information Technology Co ltd
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Hebei Tengyun Information Technology Co ltd
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02NELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR
    • H02N15/00Holding or levitation devices using magnetic attraction or repulsion, not otherwise provided for

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  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
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Abstract

The invention discloses a lifting type magnetic suspension device, which belongs to the technical field of magnetic suspension control and comprises a stator, a floater, a supporting plate, a lifting mechanism, a centering mechanism, a rack and a system panel. The stator arranged on the supporting plate is an annular magnet containing more than three magnetic field change sections, the more than three magnetic field change sections are uniformly distributed on the annular magnet, and the more than three magnetic field change sections enable the magnetic field of the stator to form an annular wavy magnetic field with local weakening or enhancement. The floater arranged on the system panel comprises a central magnet and positioning magnets which have the same number with the magnetic field change intervals and correspond to the positions of the central magnet and the positioning magnets. The central magnet provides magnetic repulsion force to lift the floater, and the positioning magnet is positioned between two adjacent magnetic field gaps of the stator by means of magnetic attraction force to overcome horizontal rotation or oscillation of the floater. The controller controls the centering mechanism and the lifting mechanism to realize automatic reset and lifting of the falling floater and dynamic suspension of the floater.

Description

Lifting type magnetic suspension device
Technical Field
The invention belongs to the technical field of magnetic suspension control, and particularly relates to a lifting type magnetic suspension device.
Background
At present, the open magnetic levitation products are mainly focused on the fields of indoor decoration, product display and science popularization education. Generally, such magnetic levitation technology needs to be realized by a permanent magnet part of a stator and a floater and an electromagnetic regulation part positioned on the stator, and can be divided into two types of lifting type and pull-up type.
The lifting type magnetic suspension system has better teaching and demonstration effects than the pull-up type because the upper part of the floater is completely an open space. The lift system requires real-time magnetic field adjustment by circuitry in the base so that the float can dynamically float above the lift plane. This requires two-dimensional control in the horizontal direction, so that the control method is more complicated than the pull-up system belonging to one-dimensional control.
In general, in existing magnetic levitation systems, regardless of the lifting type or the pulling-up type, the torque of the float in the levitation state in the Z-axis direction is mostly unconstrained, and as a result, the float is in an uncontrolled self-rotation state in the two-dimensional plane of the X, Y axis, that is, an uncontrollable slow and free rotation is generated around the Z-axis.
In order to overcome the shortcoming, in a patent of invention of six-degree-of-freedom controllable magnetic suspension mechanism and a six-degree-of-freedom control method thereof (CN108768214B) applied in 2018, 6, month and 22, a traditional suspension technology is greatly improved in terms of a magnetic circuit and a circuit structure, so that the floater can be controlled in an all-around manner in an electromagnetic traction manner after being suspended, and the floater can stably rotate and roll and has a suspension effect similar to complete stillness. However, the above method brings new problems:
firstly, the whole system is increased in volume, more complex to control, higher in power consumption and cost. In addition, at present, each time the suspension system is started or powered up again to restore the operation, the floater still needs to be placed at a correct balance position to establish an accurate suspension relation. However, this position is a small spatial space without any marks and stops. Therefore, the hand feeling is required for placing the pillow completely, and a certain skill is required. This phenomenon is particularly evident in a lift-type magnetic levitation system. It is difficult for an inexperienced operator to quickly experience and quickly master, often causing the float to fall out of the way during placement.
In particular, once such a suspension suddenly fails, the float must fall immediately. Even if the backup power supply is added, the failure can not be ensured in the operation process of the whole year and the whole month. Moreover, the condition that the floater falls is inevitable due to various reasons such as placement instability, accidental touch, even accidental electromagnetic interference and the like. And once the floater falls, the floater cannot automatically reset.
Disclosure of Invention
The invention aims to provide a lifting type magnetic suspension device, and aims to solve the technical problems that in the prior art, a floater is difficult to place, the horizontal rotation of the floater is difficult to stop, and the floater cannot be automatically reset after power failure and falling.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
a lifting type magnetic suspension device comprises a stator, a floater, a rack, a supporting plate for supporting the stator and a system panel for supporting the floater, wherein the stator is an annular magnet containing more than three magnetic field change intervals; more than three magnetic field change intervals are uniformly distributed on the annular magnet, and the more than three magnetic field change intervals are derived from weakening or enhancing of the local field intensity of the stator and are embodied as continuous fluctuation of the axial field intensity and the radial field intensity of the annular magnet synchronously to form an annular wavy magnetic field; the floater comprises a central magnet and positioning magnets matched with the wavy magnetic field, and the number of the positioning magnets is matched with the wave number and the position of the stator magnetic field; the supporting plate is provided with a magnetic field detection assembly, and the position of the floater is determined by detecting the magnetic field change of the floater; the supporting plate is connected with the lifting mechanism and is used for lifting the stator and supporting the floater to suspend; the supporting plate and the system panel are connected with the rack; the frame is provided with a centering mechanism for driving the floater to center; the magnetic field detection assembly is connected with the controller, and the controller controls the actions of the lifting mechanism and the centering mechanism by receiving signals of the magnetic field detection assembly.
Preferably, the floater comprises a polygonal magnetic steel and a circular envelope outside the polygonal magnetic steel, and the polygonal magnetic steel is combined into a closed equilateral polygonal suspension magnet by a central magnet and a positioning magnet; the corners of the polygonal magnetic steel correspond to and are equivalent to the positioning magnets, and the magnetic field at the central part of the polygonal magnetic steel forms a central magnet; the number of the sides of the polygonal magnetic steel is consistent with the number of the stator weakening points or the reinforcing magnetic steel bodies of the annular magnet.
Preferably, the stator comprises an annular magnetic steel body and an annular magnetic adjusting coil body, wherein the annular magnetic steel body can be a whole body with different axial magnetizing strengths in different annular regions, and can also be formed by splicing a plurality of small magnetic steels; the annular magnetic regulating coil body is formed by splicing a plurality of magnetic regulating coils and is arranged on the inner side of the annular magnetic steel body; more than three stator weakening points or more than three strengthening magnetic steel bodies are arranged on the annular magnetic steel body at intervals to form an annular wavy magnetic field with a magnetic field change interval; the annular magnetic regulating coil body is formed by splicing a plurality of magnetic regulating coils to form a positioning annular magnetic field; the magnetic regulating coil is electrically connected with the controller; the magnetic field detection assembly is a three-dimensional magnetic field sensor, the three-dimensional magnetic field sensor is arranged in the center of the annular magnetic regulating coil body, and the three-dimensional magnetic field sensor is in wireless or wired connection with the controller.
Preferably, the stator is an equilateral polygonal magnet, and the number of the positioning magnets of the floater is the same as the number of the sides of the polygonal magnet; the corners of the equilateral polygonal magnets form magnetic field variation intervals.
Preferably, the lifting mechanism comprises a top plate and a jacking component, the jacking component is arranged on the bottom plate and drives the top plate to lift through the jacking component, and the top plate is parallel to the supporting plate and is connected with the supporting plate.
Preferably, the rack comprises more than three parallel upright posts as sliding rails, and the edges of the top plate and the supporting plate are provided with guide holes matched with the upright posts, so that the top plate and the supporting plate can slide up and down along the sliding rails.
Preferably, the jacking part is including lifting motor, rocking arm and gyro wheel, two free ends of rocking arm are fixed in the both ends of main shaft, the output shaft drive main shaft of lifting motor rotates, the gyro wheel sets up in the end of rocking arm for with the roof butt.
Preferably, the centering mechanism comprises a power component, a connecting rod, a shifting ring positioning shaft, a shifting ring and a plurality of shifting forks, wherein the number of the shifting ring positioning shafts is a plurality, and the plurality of shifting ring positioning shafts are fixed on the system panel at intervals and are in contact with the inner wall of the shifting ring so as to ensure the radial stability of the shifting ring; the shifting forks are correspondingly arranged at intervals from head to tail, the free ends of the shifting forks are arranged on the inner sides of the shifting rings, and the vertical surfaces on the inner sides of the free ends of the shifting forks are arc-shaped and are used for pushing the floater to reset; the connecting end of the shifting fork is rotationally connected with the shifting ring through a shifting fork push shaft and is rotationally connected with the system panel through a shifting fork rotating shaft, the shifting fork push shaft is arranged on the shifting ring, and the shifting fork rotating shaft is arranged on the system panel and is arranged on the inner side of the shifting ring; one end of the connecting rod is rotationally connected with the power part, the other end of the connecting rod is rotationally connected with the edge of the shifting ring, the power part drives the shifting ring to rotate through the connecting rod, and the shifting ring drives the shifting fork to complete pushing of the floater and resetting of the shifting fork; and a circular area obtained after the plurality of shifting forks are closed is the centering position of the floater.
Preferably, the centering mechanism comprises an X-axis moving part and a Y-axis moving part, the X-axis moving part comprises a bottom frame, an X-axis guide rail and an X-axis driving part, and the Y-axis moving part comprises a middle frame, a Y-axis guide rail and a Y-axis driving part; the bottom of the rack is in sliding fit with the Y-axis guide rail, and the rack is connected with the Y-axis driving piece and used for driving the bottom plate to slide along the Y-axis guide rail; the middle frame is in sliding fit with the X-axis guide rail, and the bottom of the middle frame is connected with the X-axis driving piece and used for driving the middle frame to slide along the X-axis guide rail.
Adopt the produced beneficial effect of above-mentioned technical scheme to lie in: compared with the prior art, the invention designs more than three magnetic field change intervals on the annular magnetic field of the stator, so that the field intensity of the continuous magnetic field is sunken and raised to form an annular wavy magnetic field with local weakening and enhancement, and meanwhile, positioning magnets with the same waveform quantity as the wavy magnetic field are arranged on the periphery of the floater, the magnetic field direction of the positioning magnets is consistent with that of the central magnet, but the field intensity of the positioning magnets is far smaller than that of the central magnet and is used for attracting and positioning with the gap magnet of the stator; the stator is jacked by utilizing a jacking mechanism to lift the floater, and the floater is suspended by virtue of the magnetic force property of like poles repelling between the stator and the floater; after the floater falls down, the centering mechanism drives the floater to be centered again, and then the controller controls the action of the lifting mechanism to realize the automatic resetting and suspension of the floater.
Drawings
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
Fig. 1 is a schematic structural diagram of a lifting type magnetic levitation apparatus provided by an embodiment of the present invention;
FIG. 2 is a physical block diagram of a four-point symmetric stator with local field loss in one embodiment of the present invention;
FIG. 3 is a physical structure view of a four-point symmetrical float in the present invention;
FIG. 4 is a schematic structural diagram of the equilateral rectangular magnetic steel float of FIG. 1;
FIG. 5 is a diagram of the magnetic pole positions of the four-point symmetric stator and the floats of FIGS. 2 and 3;
FIG. 6 is a diagram showing the physical shape of the float of the square equivalent structure and the position relationship with the stator during steady state suspension;
fig. 7 is a perspective view of a stator of a lift-type magnetic suspension apparatus according to an embodiment of the present invention;
FIG. 8 is a perspective view of a four-point symmetric stator with local magnetic field enhancement in accordance with another embodiment of the present invention;
FIG. 9 is a diagram illustrating a jacking state of the lifting mechanism according to the embodiment of the present invention;
FIG. 10 is a view of the lower position of the lift mechanism of FIG. 5;
FIG. 11 is a push state diagram of the centering mechanism of FIG. 1 with the float centered;
FIG. 12 is a reset condition view of the centering mechanism of FIG. 1 after the float is centered;
FIG. 13 is a diagram of the lifting magnetic levitation apparatus of FIG. 1 in a normal operation state;
FIG. 14 is a schematic diagram of a translational structure of another lifting type magnetic levitation apparatus provided by the embodiment of the invention;
FIG. 15 is a schematic diagram of the arrangement of the effective attraction range of the stator, the float drop point sensor and the float rise sensor on the bottom surface of the system panel in the centering mechanism of the embodiment of FIG. 14;
FIG. 16 is a schematic view of the float drop point position in the centering mechanism of the embodiment of FIG. 14;
FIG. 17 is a schematic view of the centering mechanism of the embodiment of FIG. 14 attracting the float to a central location on the system panel;
FIG. 18 is a graph of the effective attraction range of the stator after centering of the float in the embodiment of FIG. 14;
in the figure: 1-stator, 101-annular magnet, 102-stator weakening point, 103-small magnetic steel, 104-magnetic regulating coil and 105-magnetic steel body; 2-floater, 201-central magnet, 202-positioning magnet, 203-magnetic steel, 204-envelope; 3-a support plate; 4-frame, 40-column, 41-guide hole; 5-a system panel; 6-a top plate; 7-lifting the motor; 8-a bottom plate; 9-a rocker arm; 10-a three-dimensional magnetic field sensor; 11-a roller; 12-a power component; 13-a connecting rod; 14-a shifting ring positioning shaft; 15-ring pulling; 16-a shifting fork; 17-a fork shaft; 18-a bottom frame; 19-X axis guide rails; 20-a middle frame; 21-Y-axis guide rails; 22-float drop point sensor; 23-a float-lift sensor; 24-a shifting fork push shaft; 25-a float frame; 26-stator effective attraction range.
Detailed Description
The technical solution in the embodiments of the present invention is clearly and completely described below with reference to the drawings in the embodiments of the present invention. It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Compared with the prior art, the lifting type magnetic suspension device provided by the embodiment of the invention has the advantages of stable suspension and automatic reset. As shown in fig. 1, the system comprises a stator 1, a floater 2, a frame 4, a support plate 3 for supporting the stator 1, and a system panel 5 for supporting the centering device and the floater 2 after falling, wherein the stator 1 is an annular magnet 101 containing more than three magnetic field change intervals, the more than three magnetic field change intervals are alternated on the annular magnet 101, as shown in fig. 2, the magnetic field change intervals can enable the magnetic field of the stator to form an annular wavy magnetic field with local weakening or strengthening, namely, the field intensity of the magnetic field generates continuous 'concave' and 'convex' to form an annular wavy magnetic field; the floater 2 comprises a central magnet 201 and a positioning magnet 202 which has the same wavenumber and the corresponding position with the stator wave magnetic field, the magnetic field direction of the positioning magnet 202 is consistent with that of the central magnet, but the field intensity is far smaller than that of the central magnet, the positioning magnet is used for attracting and positioning with the stator gap magnet and is jointly arranged on the floater frame 25, as shown in fig. 3. While the simplified actual float is shown in figure 4. A simplified comparison of the front and rear floats and their suspended state is shown in figures 5 and 6 and will be described in detail later.
The supporting plate 3 is also provided with a magnetic field detection assembly for detecting the central magnetic field of the floater 2, and the supporting plate 3 and the top plate 6 are connected with the lifting mechanism for lifting the stator 1 and supporting the floater 2 to suspend; the supporting plate 3 and the system panel 5 are both connected with the frame 4; the frame 4 is provided with a centering mechanism for driving the floater 2 to be centered; the magnetic field detection assembly is connected with the controller, and the controller controls the actions of the lifting mechanism and the centering mechanism through the power amplifier circuit by receiving signals of the magnetic field detection assembly. When the floater falls, the supporting plate is driven to descend by the lifting mechanism, so that the stator can descend to a position below the height of the floating magnetic field of the floater, which cannot be influenced by the lifting magnetic field of the stator, and the floater is driven to reset by the centering mechanism; after the floater is reset, the stator is jacked by the jacking mechanism to be close to the floater from the lower part, and the floater is suspended by virtue of the magnetic repulsion between the stator and the floater. When the floater falls down again, the centering mechanism is continuously used for driving the floater to return to the center, and the suspension is realized again.
In embodiment 1, a three-dimensional assembly view of a stator is shown in fig. 7, where the stator 1 includes an annular magnetic steel body and an annular magnetic regulating coil body, the annular magnetic steel body is formed by splicing a plurality of small circular magnetic steels 103, the annular magnetic regulating coil body is formed by splicing a plurality of magnetic regulating coils 104, and the annular magnetic regulating coil body is disposed inside the annular magnetic steel body; more than three stator weakening points 102 are arranged on the annular magnetic steel body at intervals or more than three reinforcing magnetic steel bodies 105 shown in a three-dimensional assembly figure 8 are arranged on the annular magnetic steel body at intervals to form an annular wavy magnetic field with a magnetic field change interval; a plurality of magnetic regulating coils 104 are spliced to form an annular magnetic regulating coil body to form a positioning annular magnetic field; the magnetic field adjusting coil 104 is electrically connected with the controller, the magnetic field detection component is a three-dimensional magnetic field sensor 10, the three-dimensional magnetic field sensor 10 is arranged in the center of the annular magnetic field adjusting coil body, and the three-dimensional magnetic field sensor 10 is in wireless or wired connection with the controller. In addition, the annular magnetic steel body can also be an integral annular magnetic steel, and as long as the axial magnetizing intensity in different annular areas is different, an annular wavy magnetic field can also be realized. In fig. 7 and 8, the ring-shaped magnetic steel body provides a supporting magnetic field for lifting and stabilizing the floater; the annular magnetic regulating coil body provides a magnetic regulating magnetic field, so that the stability and the positioning of the floater can be kept, and the suspension height of the floater can be regulated. When the floater falls, the three-dimensional magnetic field sensor 10 immediately detects the position change of the floater, sends related signals to the controller in real time, and the controller lowers the rocker arm through the lifting motor and starts the centering mechanism to reset the floater. And when the floater resets, the controller sends a jacking instruction to the jacking motor. The jacking state of the stator is shown in fig. 9.
The stator electromagnetic structure of the invention has three characteristics: a plurality of points are uniformly distributed with annular wavy magnetic fields more than three points; the magnetic field adjusting device comprises a magnetic field adjusting coil array capable of simultaneously performing suspension control and rotation control; the magnetic regulating coil array adopts a distributed coil array control mode based on an FPGA or a plurality of single-chip microcomputers.
The annular magnetic field with gap characteristics of the stator magnetic field regulation part shown in fig. 7 can be simplified by symmetrically removing a plurality of permanent magnets from the complete uniform annular magnetic field, and has no relation with the arrangement and the position of the coil. In fig. 7, the number of the magnetic adjustment coils is 8, and if the adjacent coils are connected in parallel or in series, the adjacent coils are grouped in pairs and controlled in a unified manner, and the magnetic adjustment coils are equivalent to 4 magnetic adjustment coils in a common magnetic suspension structure.
In addition, the three-dimensional magnetic field sensor adopts an MLX90393 chip, and the acquired data directly pass through I2The C bus is transmitted to an FPGA chip or a corresponding singlechip control system to perform subsequent high-speed real-time processing to form all control information required by the suspension system, and the control information is transmitted to a coil controlled unit of the stator through a driving circuit.
The magnetic field variation interval in the electromagnetic structure of the stator shown in fig. 2 is caused by the local absence of the toroidal magnetic field. In fact, the shape of the stator magnet may be a ring structure with symmetrical gaps, or may be formed by a complete equilateral triangle, a square, a rectangle, and equal-length polygons with a certain number of side lengths, or may be a corresponding overall shape formed by splicing small pieces of magnetic material.
When a polygonal magnetic field such as a triangle, a rectangle or a polygon is directly used instead of a ring magnetic field, the corners of the polygonal magnet form a magnetic field change section.
On the other hand, the extraction of a part of the magnets in the stator entails a loss of the overall field strength, a reduction in the space utilization and in the energy density of the magnetic field, with the result that the levitation height of the float is directly reduced. If the system has the requirement that the total field strength cannot be changed and the float suspension height must be ensured or even increased, the method of generating the wave-shaped magnetic field by drawing the gap formed by the magnets is difficult to accomplish. Of course, this can also be solved by enhancing the overall field strength of the magnet in use, but the space utilization rate still cannot be improved.
In contrast to forming a locally weakened annular wavy magnetic field with gaps, the same positioning effect can be achieved if the weakened gap annular magnetic dots are strengthened on the basis of a uniform annular magnetic field. Since the weakening and strengthening are relative, the remaining locations are relatively weakened as long as there are relative strengthening points. The analysis of the effectiveness of the 'bulge' type intensified circular magnetic field is the same as the analysis method of the gap type weakened circular magnetic field, and the positioning conclusion is consistent.
In fig. 8, the annular magnets of the stator are uniformly distributed with the reinforced magnetic steel bodies 105, so that the stator has a fluctuating annular magnetic field with local reinforcement, and a physical structure of the stator with a raised annular magnetic field is formed, wherein the raised annular magnetic field can maintain or improve the suspension height of the floater and can ensure the stability and the positioning of the floater.
The magnetic field of fig. 8, the ferromagnetic steel body 105 is realized by a magnet of the same diameter but with an increased height. In fact, the basic principle of this method is only local field intensification, not necessarily an increase in magnet volume. Therefore, equal-volume magnets with higher field intensity density can be used at the magnetic field strengthening point to replace large-volume magnets with equal field intensity density, and even the strengthening can be completed by adding special strengthening magnets near the magnetic field needing strengthening. Thus, the effect of the raised annular magnetic field can be received under the condition that all the magnets have the same volume. However, such methods have a common disadvantage in that stator magnets of different sizes are required in order to form a symmetrical gap toroidal magnetic field structure. This can cause some inconvenience in the specific implementation.
It can be seen from the above analysis that 4 groups of magnetic steels can form an annular lifting magnetic field with 4 gaps (or protrusions). If other polygonal magnetic field modes need to be formed, only the permanent magnet at the corresponding position needs to be removed (or moved), and the method is various and very flexible.
As shown in fig. 3, the float is equipped with a central magnet at its geometric center to generate self-lifting buoyancy; since the stator in fig. 2 has a magnetic field gap, the float needs to be provided with the same number of positioning magnets as the stator gap magnetic field at its periphery, and the number of positioning magnets is also the same as the stator gap magnetic field.
The positioning magnet also has the characteristic of multipoint symmetry, the magnetic field direction of the positioning magnet is consistent with that of the central magnet, but the field intensity of the positioning magnet is far smaller than that of the central magnet, and the positioning magnet is only used for attracting and positioning with the gap magnet of the stator, so that the suspension effect is not influenced. Thus, fig. 3 provides 4 corresponding positioning magnets, corresponding to the number of gaps of the stator weakening point 102. The positioning magnet 202 is positioned above the annular magnet 101 between two adjacent stator gaps in a suspension state, so that the stators and the floats form a complementary suspension mode based on the characteristics of the wavy magnetic field.
When the suspension is stabilized, the stator and the rotor are geometrically coaxial, the lifting and the suspension magnetic fields are concentric, and the stator and the rotor are in an accurate dynamic balance state. The float magnetic field may be a ring magnetic field having the same radius as the stator magnetic field, a ring magnetic field having a different radius, or a central magnetic field generated by a single magnet.
The other main characteristic of the structure is that the direction of the magnetic field of the lower surface of each positioning magnet of the levitation magnetic field is different from the direction of the wavy magnetic field of the upper surface of the stator below the positioning magnet, and the positioning magnet can be just attracted to the position with the maximum field intensity in the levitation process, namely the middle position of two gaps of the stator magnetic field.
Because the lifting magnetic field of the stator and the suspension magnetic field of the floater have the relationship of mutual exclusion of suspension and complementary positioning, the rotating moment generated by various disturbances when the floater is in an unconstrained state of a rotation dimension on a Z axis can be naturally overcome, and a completely static or slightly swinging suspension state is achieved. Therefore, in the case of normal levitation, the float can overcome the spin torque by itself without performing a special rotation control, and finally can gradually enter a steady state, as shown in fig. 5.
If the float permanent magnet in fig. 3 is contracted and simplified in physical shape to the maximum extent, the float permanent magnet can be equivalent to a whole magnet, and the float permanent magnet can be called a compact multipoint symmetrical suspension body. The magnet can be a complete equilateral triangle, square, rectangle or polygon with a certain side length corresponding to the stator magnet, or a corresponding integral shape formed by splicing small blocks of magnetic materials.
In embodiment 1, the float 2 is an equilateral polygonal magnetic steel that is formed by combining the central magnet 201 and the positioning magnet 202 into a whole, the number of sides of the equilateral polygonal magnetic steel is the same as the number of magnetic field waves of the stator, and the corners of the equilateral polygonal magnetic steel are physically and structurally equivalent to the positioning magnet. In fact, the overall field strength of the float now also has a wave-like character. The corners of the equilateral polygon magnet steel are equivalent to the positioning magnets 202, and the magnetic field at the central part of the polygon magnet steel is equivalent to the central magnet 201. The floater shown in fig. 4 uses square magnetic steel 203, so that a suspension magnetic field with 4 'salient points' is provided, the magnetic steel 203 is packaged in a circular envelope 204 to form a circular floater, and the circular floater can be conveniently pushed and centered by a shifting fork when the circular floater is initially placed or falls off in operation. The physical appearance of the floater with a square equivalent structure and the position relation with the stator in steady suspension are shown in fig. 6, and the suspension and positioning characteristics can be obtained by comparing fig. 5 with fig. 6.
In an embodiment of the present invention, as shown in fig. 9 and 10, the lifting mechanism includes a top plate and a lifting member, the lifting member is disposed on the bottom plate 8, the lifting member drives the top plate 6 to move up and down, and the top plate 6 is parallel to the supporting plate 3 and connected to the supporting plate 3. Wherein, the jacking part is including lifting motor 7, rocking arm 9 and gyro wheel 11, two free ends of rocking arm 9 are fixed in the both ends of main shaft, the output shaft drive main shaft of lifting motor 7 rotates, gyro wheel 11 sets up in the end of rocking arm 9 for with 6 butts of roof. The servo motor can be selected for use as the lifting motor, and the positive and negative rotation of the servo motor drives the rocker arm to swing, so that the top plate is lifted by the roller at the top of the rocker arm. When the angle between the rocker arm and the bottom plate is 0 degree and 180 degrees, the position of the top plate is the lowest; when the angle is 90 °, the top plate is located highest.
When the floater centering process is started, the rocker arm swings downwards, the supporting plate descends to enable the stator to be far away from the system panel, and therefore the magnetic field intensity in the center of the system panel is reduced to the extent that the magnetic field intensity is not enough to support the floater or influence the position of the floater. Only in this way it is possible for the float to be pushed exactly to the centre of the system, i.e. to the centre of the lifting field of the stator on the support plate. Then, the rocker arm swings upwards, the jacking supporting plate rises to drive the stator to rise, and the magnetic repulsion force borne by the floater is gradually increased until the floater rises; further, the float is continuously raised as the stator is raised on the support plate. When the rocker arm rotates to 90 degrees, the rocker arm reaches the highest point and stops rising, and the floater can stably suspend.
In addition, the jacking component can also adopt an electric push rod, a hydraulic cylinder or an air cylinder to realize the lifting of the top plate.
The frame structure is further simplified, as shown in fig. 1, 9 and 10, the frame 4 includes more than three vertical posts 40, four vertical posts are selected from the drawing, and the four corners of the top plate 6 and the supporting plate 3 are provided with guide holes 41 matched with the vertical posts 40. By adopting the structure, the top plate and the supporting plate can be lifted up and down along the upright post as the sliding rail, and the position of the stator on the supporting plate is ensured to be fixed.
In the particular embodiment shown in fig. 1, 9 and 10, the centering mechanism is shown in fig. 11 and 12. The centering mechanism comprises a power part 12, a connecting rod 13, a shifting ring positioning shaft 14, a shifting ring 15 and a plurality of shifting forks 16, wherein the shifting ring positioning shafts 14 are arranged in a plurality, the shifting ring positioning shafts 14 are fixed on a system panel at intervals and tightly abut against the inner wall of the shifting ring 15, the shifting forks 16 are arranged on the shifting ring 15 at intervals, the free ends of the shifting forks 16 are arranged on the inner side of the shifting ring 15, and the vertical surface on the inner side of the free ends of the shifting forks 16 is arc-shaped, so that all the shifting forks jointly enclose an annular area; the connecting end of the shifting fork 16 is connected with the shifting ring 15 through a shifting fork push shaft 24, is connected with the system panel 5 through a shifting fork rotating shaft 17, and is arranged at the inner side of the shifting ring 15.
One end of a connecting rod 13 is rotationally connected with a power part 12, the other end of the connecting rod is rotationally connected with a shifting ring 15, the power part 12 drives the shifting ring 15 to rotate through the connecting rod 13 to drive a shifting fork 16 to complete pushing of a floater 2 and self resetting of the shifting fork 16, and the center of the shifting ring is accurately superposed with the magnetic field center of a stator; the circular area obtained after the closing of several forks 16 is the centering position of the float 2. The power part comprises a centering motor and a rotary table, an output shaft of the centering motor is coaxially fixed with the rotary table, and the end part of the connecting rod is rotatably connected with the edge of the rotary table.
When the float deviates from the floating center by a certain distance, the float can fall out of control to a circular area surrounded by the float shifting fork 16 on the system panel 5. At the moment, the three-dimensional magnetic field sensor 10 at the center of the stator 1 immediately senses and transmits related signals to the controller, the controller sends out an instruction, the servo motor in charge of lifting swings the arm downwards, and the stator system can be lowered to a position below the height of a floating magnetic field of the floater, which cannot be influenced by the lifting magnetic field; at this moment, a servo motor of the centering mechanism operates, the servo motor drives the turntable to rotate, so that the connecting rod is driven to swing, the connecting rod drives the shifting ring to rotate in a small range by taking the lifting center as an axis, meanwhile, the shifting forks rotate around shifting fork rotating shafts under the pushing of the shifting ring pushing shafts, the shifting forks cooperate with the pushing floater together to return to the central position of the area to reside, and the floating is waited to be floated, as shown in fig. 11. Then, the plurality of forks are returned to their original positions as shown in fig. 12.
When the lifting motor of the lifting mechanism swings upwards to lift the supporting plate 3 with the stator 1 in place, the floater 2 is also pushed to a normal suspension height by the lifting magnetic field of the stator to complete automatic reset, and the complete working state diagram of the embodiment is shown in fig. 13.
In view of the fact that the push type centering mechanism in the figure 1 is realized above the system panel, the push type centering mechanism is simple in structure and easy to assemble, debug and maintain. But has the disadvantage that the mechanical structure of the centering is completely exposed and somewhat messy. In addition, for the demonstration attention received by the magnetic suspension system, the action amplitude of the centering system is large, which is likely to be noisy, and the demonstration effect of the suspension body may be affected.
In another embodiment of the present invention, a pull-type centering mechanism is used, as shown in FIG. 14. The centering mechanism comprises an X-axis moving part and a Y-axis moving part, the X-axis moving part comprises a bottom frame 18, an X-axis guide rail 19 and an X-axis driving part, and the Y-axis moving part comprises a middle frame 20, a Y-axis guide rail 21 and a Y-axis driving part; the bottom plate 8 is in sliding fit with the Y-axis guide rail 21, and the bottom of the bottom plate 8 is connected with the Y-axis driving piece and used for driving the bottom plate 8 to slide along the Y-axis guide rail 21; the middle frame 20 is in sliding fit with the X-axis guide rail 19, and the bottom of the middle frame 20 is connected with an X-axis driving member for driving the middle frame 20 to slide along the X-axis guide rail 19.
Further optimizing the above technical solution, as shown in fig. 15. The elliptical area 26 enclosed by the dotted line in the figure is the strong magnetic range of the stator attracting the float to deviate from the floating position in the normal floating state, i.e. the effective attraction range of the stator, corresponding to the position of the stator lifting magnet below the system panel, i.e. the possible falling interval of the float. The solid line circle at the center of each ellipse is the position of a floater falling point sensor 22 embedded below the system panel, the solid line circle at the center of the system panel is the position of a floater floating sensor 23 embedded below the system panel, the floater falling point sensor 22 is arranged right above the gap magnet 101 of the stator 1, and the floater floating sensor 23 is arranged at the center of the system panel 5 and corresponds to the center of the stator 1.
When the floater falls to a certain drop point, the floater is attracted by the magnetic field below the floater. The lifting mechanism does not drop, or does not drop too much, in order to maintain sufficient suction to the float. Then, the middle frame is horizontally moved. The float attached to the system panel is necessarily "dragged" by the magnetic field to move in the same way on the system panel. The falling point position of the floater is determined by the floater falling point sensor, and the controller can pull the floater to move to a position suitable for the floater to float on a system panel in a stator translation mode according to the falling point position information of the corresponding sensor. The floating position is determined by a floating position sensor below the system panel. Fig. 16 and 17 are schematic diagrams of a floater falling click being dragged to the center of a system panel.
When the float-lift sensor detects that the float has reached the float-lift position, the lift mechanism is actuated, and the support plate is lowered to a height at which its magnetic field no longer causes the float to move further, and the lift center of the stator is moved to a position aligned with the float-lift sensor, as shown in fig. 18.
After the float and the stator are respectively prepared for floating, the lifting mechanism lifts the stator to lift the float, and a new suspension process is completed.
According to the figures 1 and 14, the centering work of the floater can be carried out in two modes of pushing and traction, the automatic resetting of the floater can be realized, the worries of people who need to reset after the floater falls can be thoroughly solved, and the translation, rotation and other related demonstration functions of the floater in a certain range in a suspension state are greatly facilitated and expanded. Particularly, the basic magnetic circuit structure is changed, so that the floater can naturally tend to be stable in the rotation dimension of the Z axis after being suspended, and the floater becomes one of the intrinsic characteristics of the suspension technology.
Through a series of complete measures of realizing the centering, lifting and electronic fine adjustment of the floater until the floater is stably suspended or controllably rotated and the like, the system can be reduced in size and power consumption, the operation is more stable and accurate, a user can feel flexible and convenient in operation, a brand-new basic framework and a regulation and control strategy are provided for the existing magnetic suspension products and technologies, and the higher requirements of the all-dimensional and full-dimensional normal operation of the magnetic suspension products and technologies are met.
In the description above, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described and will be readily apparent to those of ordinary skill in the art without departing from the spirit of the present invention, and thus the present invention is not limited to the specific embodiments disclosed above.

Claims (7)

1. A lifting type magnetic suspension device is characterized in that: the magnetic levitation permanent magnet synchronous motor comprises a stator, a floater, a rack, a supporting plate for supporting the stator and a system panel for supporting the floater, wherein the stator is an annular magnet containing more than three magnetic field change intervals; more than three magnetic field change intervals are uniformly distributed on the annular magnet, and the more than three magnetic field change intervals are derived from weakening or enhancing of the local field intensity of the stator and are embodied as continuous fluctuation of the axial field intensity and the radial field intensity of the annular magnet synchronously to form an annular wavy magnetic field; the floater comprises a central magnet and positioning magnets matched with the wavy magnetic field, and the number of the positioning magnets is matched with the wave number and the position of the stator magnetic field; the supporting plate is provided with a magnetic field detection assembly, and the position of the floater is determined by detecting the magnetic field change of the floater; the supporting plate is connected with the lifting mechanism and is used for lifting the stator and supporting the floater to suspend; the supporting plate and the system panel are connected with the rack; the frame is provided with a centering mechanism for driving the floater to center; the magnetic field detection assembly is connected with the controller, and the controller controls the actions of the lifting mechanism and the centering mechanism by receiving signals of the magnetic field detection assembly;
the centering mechanism comprises a power part, a connecting rod, a shifting ring positioning shaft, a shifting ring and a plurality of shifting forks, wherein the shifting ring positioning shafts are fixed on a system panel at intervals and are in contact with the inner wall of the shifting ring; the connecting end of the shifting fork is rotationally connected with the shifting ring through a shifting fork push shaft and is rotationally connected with the system panel through a shifting fork rotating shaft, the shifting fork push shaft is arranged on the shifting ring, and the shifting fork rotating shaft is arranged on the system panel and is arranged on the inner side of the shifting ring; one end of the connecting rod is rotationally connected with the power part, the other end of the connecting rod is rotationally connected with the edge of the shifting ring, the connecting rod is equivalent to a crank-connecting rod mechanism, the power part drives the shifting ring to rotate through the connecting rod, and the shifting ring drives the shifting fork to complete pushing of the floater and resetting of the shifting fork; the diameter of a circular area enclosed by the plurality of shifting forks when the shifting forks are extended is larger than that of the stator annular magnetic steel body, and the circular area obtained after contraction and enclosure is the centering position of the floater;
or the centering mechanism comprises an X-axis moving part and a Y-axis moving part, the X-axis moving part comprises a bottom frame, an X-axis guide rail and an X-axis driving part, and the Y-axis moving part comprises a middle frame, a Y-axis guide rail and a Y-axis driving part; the bottom of the rack is in sliding fit with the Y-axis guide rail, and the rack is connected with the Y-axis driving piece and used for driving the bottom plate to slide along the Y-axis guide rail; the middle frame is in sliding fit with the X-axis guide rail, and the bottom of the middle frame is connected with the X-axis driving piece and used for driving the middle frame to slide along the X-axis guide rail.
2. The lift-off magnetic levitation device of claim 1, wherein: the floater comprises polygonal magnetic steel and a circular envelope outside the polygonal magnetic steel, and the polygonal magnetic steel is combined into a closed equilateral polygonal suspension magnet by a central magnet and a positioning magnet; the corners of the polygonal magnetic steel correspond to and are equivalent to the positioning magnets, and the magnetic field at the central part of the polygonal magnetic steel forms a central magnet; the number of the sides of the polygonal magnetic steel is consistent with the number of the stator weakening points or the reinforcing magnetic steel bodies of the annular magnet.
3. The lift-off magnetic levitation device of claim 1, wherein: the stator comprises an annular magnetic steel body and an annular magnetic adjusting coil body, wherein the annular magnetic steel body is a whole body with different axial magnetizing strengths in different annular areas, or the annular magnetic steel body is formed by splicing a plurality of small magnetic steels; the annular magnetic regulating coil body is formed by splicing a plurality of magnetic regulating coils and is arranged on the inner side of the annular magnetic steel body; more than three stator weakening points or more than three strengthening magnetic steel bodies are arranged on the annular magnetic steel body at intervals to form an annular wavy magnetic field with a magnetic field change interval; the annular magnetic regulating coil body is formed by splicing a plurality of magnetic regulating coils to form a positioning annular magnetic field; the magnetic regulating coil is connected with the controller; the magnetic field detection assembly is a three-dimensional magnetic field sensor, the three-dimensional magnetic field sensor is arranged in the center of the annular magnetic regulating coil body, and the three-dimensional magnetic field sensor is in wireless or wired connection with the controller.
4. The lift-off magnetic levitation device of claim 1, wherein: the stator is an equilateral polygon magnet, and the number of the positioning magnets of the floater is the same as the number of the sides of the polygon magnet; the corners of the equilateral polygonal magnets form magnetic field variation intervals.
5. The lift-off magnetic levitation device of claim 1, wherein: the lifting mechanism comprises a top plate and a jacking component, the jacking component is arranged on the bottom plate and drives the top plate to lift through the jacking component, and the top plate is parallel to the supporting plate and is connected with the supporting plate.
6. The lift-off magnetic levitation device of claim 5, wherein: the frame includes three or more parallel stands, the edge of roof and backup pad all is equipped with the guiding hole with stand matched with.
7. The lift-off magnetic levitation device of claim 5, wherein: the jacking part comprises a lifting motor, a rocker arm and a roller, two free ends of the rocker arm are fixed at two ends of the main shaft, an output shaft of the lifting motor drives the main shaft to rotate, and the roller is arranged at the tail end of the rocker arm and used for being abutted against the top plate.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE1031288B1 (en) * 2023-01-24 2024-08-26 Continental Structures Sprl Method for easily stabilizing a decorative object in magnetic levitation

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112767801B (en) * 2021-03-04 2022-08-30 河北腾云信息技术有限公司 Traveling type magnetic suspension demonstration system and float static suspension and traveling control method
CN114229245B (en) * 2021-12-30 2023-05-12 中科微影(浙江)医疗科技有限公司 Damping system for magnetic resonance equipment transportation
CN114803598B (en) * 2022-05-11 2024-02-27 安徽理工大学 Controllable magnetic circuit permanent magnet suspension idler
CN114636399B (en) * 2022-05-17 2022-11-18 杭州泰尚智能装备股份有限公司 New energy vehicle electronic water pump rotor axial clearance detection device and control method thereof

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2174403Y (en) * 1993-07-08 1994-08-17 徐荣祥 Infinitely variable speed bicycle
CN1437313A (en) * 2002-02-08 2003-08-20 唐建一 Control system of large magnetic suspension plant
CN102570927A (en) * 2012-03-07 2012-07-11 中磁力(深圳)科技有限公司 Magnetic levitation device with function of automatically lifting suspended matter
CN204687868U (en) * 2015-06-16 2015-10-07 肇庆市衡艺实业有限公司 Self-floating magnetic levitation device
CN105553337A (en) * 2016-02-02 2016-05-04 杨欢 Magnetic suspension system
CN105666179A (en) * 2014-11-18 2016-06-15 西安志越机电科技有限公司 Double-station pressing device for machining of shift forks
CN206498525U (en) * 2017-01-12 2017-09-15 吉林航盛电子有限公司 It is a kind of to strengthen the magnetic circuit device and loudspeaker in magnetic gap magnetic field
CN107465365A (en) * 2017-09-29 2017-12-12 武汉卿汉盛世文化创意有限责任公司 Omnidirectional's magnetic levitation system
CN207732665U (en) * 2017-12-31 2018-08-14 上海初拓科技有限公司 It is a kind of can power-off protection magnetic levitation system
CN108768214A (en) * 2018-06-22 2018-11-06 河北医科大学第二医院 Six degree of freedom controllable type magnetic suspension mechanism and its six degree of freedom control method
CN110323969A (en) * 2019-07-05 2019-10-11 深圳市璇芙科技有限公司 A kind of magnetic levitation system
CN110677075A (en) * 2019-10-29 2020-01-10 哈尔滨工业大学 Two-degree-of-freedom magnetic suspension device
CN210186447U (en) * 2019-06-13 2020-03-27 班尉翔 Magnetic suspension simulation toy

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BR112015004409A2 (en) * 2012-10-05 2017-07-04 Koninklijke Philips Nv rotary positioning device
CN205430095U (en) * 2016-02-06 2016-08-03 青岛鲁渝能源科技有限公司 Magnetic levitation system who can be used to wireless power supply equipment
CN108386481B (en) * 2018-03-05 2019-02-22 青岛理工大学 Halbach permanent magnet array-based high-linearity magnetic suspension vibration isolation device, actuator and method

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2174403Y (en) * 1993-07-08 1994-08-17 徐荣祥 Infinitely variable speed bicycle
CN1437313A (en) * 2002-02-08 2003-08-20 唐建一 Control system of large magnetic suspension plant
CN102570927A (en) * 2012-03-07 2012-07-11 中磁力(深圳)科技有限公司 Magnetic levitation device with function of automatically lifting suspended matter
CN105666179A (en) * 2014-11-18 2016-06-15 西安志越机电科技有限公司 Double-station pressing device for machining of shift forks
CN204687868U (en) * 2015-06-16 2015-10-07 肇庆市衡艺实业有限公司 Self-floating magnetic levitation device
CN105553337A (en) * 2016-02-02 2016-05-04 杨欢 Magnetic suspension system
CN206498525U (en) * 2017-01-12 2017-09-15 吉林航盛电子有限公司 It is a kind of to strengthen the magnetic circuit device and loudspeaker in magnetic gap magnetic field
CN107465365A (en) * 2017-09-29 2017-12-12 武汉卿汉盛世文化创意有限责任公司 Omnidirectional's magnetic levitation system
CN207732665U (en) * 2017-12-31 2018-08-14 上海初拓科技有限公司 It is a kind of can power-off protection magnetic levitation system
CN108768214A (en) * 2018-06-22 2018-11-06 河北医科大学第二医院 Six degree of freedom controllable type magnetic suspension mechanism and its six degree of freedom control method
CN210186447U (en) * 2019-06-13 2020-03-27 班尉翔 Magnetic suspension simulation toy
CN110323969A (en) * 2019-07-05 2019-10-11 深圳市璇芙科技有限公司 A kind of magnetic levitation system
CN110677075A (en) * 2019-10-29 2020-01-10 哈尔滨工业大学 Two-degree-of-freedom magnetic suspension device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE1031288B1 (en) * 2023-01-24 2024-08-26 Continental Structures Sprl Method for easily stabilizing a decorative object in magnetic levitation

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