A two-way magnetic levitation brushed motor device

Abstract

The present invention discloses a two-way magnetic levitation brushed motor device, which includes a motor housing, a motor shaft branch and an end cover. The end cover is arranged at the bottom end of the motor housing. Axial holes are formed at the centers of both the motor housing and the end cover. The motor shaft branch is arranged between the two axial holes, and bearings are provided at the connection parts of the motor shaft branch with the motor housing and the end cover. One end of the motor shaft branch away from the end cover extends out of the motor housing, and a transmission connecting shaft is arranged at the top end of the motor shaft branch. The present invention realizes the transmission of motion by relying on the electromagnetic effect, and no longer needs to install elastic structures such as torsion bars. On the one hand, it avoids the situation that the elastic structure is easily damaged during use, resulting in a short service life of the motor. On the other hand, it enables the motor with a unit volume to transmit a larger torque value. The combination of a commutator and a brush needle is used to provide a transmission medium to introduce the external circuit current into the rotor coil winding to generate a magnetic field, and the working stability is relatively high.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and particularly to a bidirectional magnetic levitation brushed motor device. Background Art

[0002] With the continuous improvement of people's living standards, electric toothbrushes have begun to enter people's daily lives, replacing traditional toothbrushes to achieve more ideal and convenient brushing effects.

[0003] Existing electric toothbrushes usually use motors to drive, and the vibration of the toothbrush head plays a role in cleaning teeth. Generally, the motors in existing electric toothbrushes need to be installed with springs or torsion bars similar to torsion springs. Such structures are prone to damage and difficult to repair during use. Therefore, the service life of the motor often depends on how long the above structures can be used. And the use of the above structural design results in low load-bearing capacity of the motor, small torque that can be transmitted by the motor per unit volume, and large swing changes of the motor shaft when bearing different loads, and the use effect is not stable enough.

[0004] In addition, the movement trajectories of existing electric toothbrushes are generally radial left and right swings, without axial telescopic functions. However, when people brush their teeth in daily life, they not only need to swing up and down to clean teeth (radial swing), but also need to move left and right (axial telescopic) to achieve the purpose of comprehensive cleaning, and the safety protection of the electric toothbrush motor needs to be further strengthened.

[0005] Therefore, it is necessary to invent a bidirectional magnetic levitation brushed motor device to solve the above problems. Summary of the Invention

[0006] The purpose of the present invention is to provide a bidirectional magnetic levitation brushed motor device, which realizes the transmission of motion by relying on electromagnetic effects and no longer needs to install elastic structures such as torsion bars. On the one hand, it avoids the situation that the elastic structure is prone to damage during use, resulting in a short service life of the motor. On the other hand, it enables the motor per unit volume to transmit a larger torque value, uses the combination of a commutator and brush needles to provide a propagation medium, achieves the purpose of comprehensive cleaning and a safe effect, so as to solve the above deficiencies in the technology.

[0007] To achieve the above object, the present invention provides the following technical solution: A two-way magnetic levitation brushed motor device, comprising a motor housing, a motor shaft branch and an end cover. The end cover is arranged at the bottom end of the motor housing. Axial holes are provided at the centers of both the motor housing and the end cover. The motor shaft branch is arranged between the two axial holes, and bearings are provided at the connection parts of the motor shaft branch with the motor housing and the end cover. One end of the motor shaft branch away from the end cover extends out of the motor housing, and a transmission connecting shaft is provided at the top end of the motor shaft branch. An insulating protective housing is provided on the side of the end cover away from the motor housing. A commutator is sleeved on the outer side of the bottom of the motor shaft branch. Two symmetrically distributed brush needles are provided on both sides of the bottom of the commutator. The cross-sectional shape of the brush needle is set as an L shape, and the top end and the bottom end of the brush needle are respectively inserted into the commutator and the end cover. A transmission unit is arranged inside the motor housing. The transmission unit is composed of a stator assembly and a rotor assembly, and the rotor assembly is arranged inside the stator assembly;

[0008] The stator assembly includes a stator skeleton and magnetic steel. Placing grooves are provided on both sides of the stator skeleton. The magnetic steel is arranged inside the placing grooves. Limiting frames are provided on both sides of the inner wall of the stator skeleton;

[0009] The rotor assembly includes a rotor iron core and a coil winding. The rotor iron core is stacked on the outer side of the motor shaft branch. The rotor iron core is composed of rotor teeth and pole shoes, and the rotor teeth and the pole shoes are integrally arranged. The coil winding is wound around the outer side of the rotor teeth;

[0010] The number of the placing grooves is set as four. The four placing grooves are symmetrically distributed about the bisector of the rotor iron core. The spacing angles between the four placing grooves are not equal. The heights of the four magnetic steels are staggered, and the heights of adjacent two magnetic steels are not equal. The magnetic steel and the rotor iron core form a self-absorbing surface and a non-self-absorbing surface, and the area of the self-absorbing surface is larger than that of the non-self-absorbing surface.

[0011] Preferably, the motor shaft branch and the transmission connecting shaft are coaxially arranged. A plugging groove is provided at the bottom end of the transmission connecting shaft. The top end of the motor shaft branch is arranged inside the plugging groove, and the motor shaft branch is in transmission connection with the transmission connecting shaft.

[0012] Preferably, the number of the transmission units is set as one or more. The preset values mentioned in the multiple transmission units are set as one or more.

[0013] Preferably, the cross-sectional shape of the motor housing is set as flat or circular. Both the end cover and the stator skeleton match the inner contour of the motor housing, and the end cover and the motor housing are riveted and connected. The rotor iron core matches the inner wall of the stator skeleton.

[0014] Preferably, the winding directions of the coil windings on the rotor teeth are the same. The two drive units are electrically connected through a coil tap. The four coil winding tap wires are respectively set as Coil 1, Coil 2, Coil 3, and Coil 4. The head of Coil 1 is connected to the tail of Coil 2, the head of Coil 3 is connected to the tail of Coil 4. The heads of Coil 2 and Coil 4 are connected on one side of the commutator. There are lugs on both sides of the top of the commutator. The tail of Coil 1 and the tail of Coil 3 are connected to the lugs of the commutator.

[0015] Preferably, the coil windings of the coil are respectively set as upper and lower windings and left and right windings. The magnetic fields after the upper and lower windings are energized are the same, and the magnetic fields after the left and right windings are energized are opposite.

[0016] Preferably, the four permanent magnets in the drive unit are divided into two groups. The number of permanent magnets in each group is set to two, and the polarities of the two permanent magnets in each group are opposite. The upper and lower magnetic poles of the two groups of permanent magnets correspond to the same.

[0017] Preferably, the brush needle is electrically connected to an external power supply, and the brush needle is electrically connected to the coil winding through a commutator.

[0018] Preferably, the surface of the rotor core is coated with 3M insulating powder.

[0019] In the above technical solution, the technical effects and advantages provided by the present invention are as follows:

[0020] By relying on the electromagnetic effect to achieve the transmission of motion, there is no longer a need to install elastic structures such as torsion bars. On the one hand, it avoids the situation that the elastic structure is easily damaged during use, resulting in a short service life of the motor. On the other hand, it enables the motor of unit volume to transmit a larger value of torque. Using the combination of the commutator and the brush needle to provide a propagation medium, introducing the external circuit current into the rotor coil winding to generate a magnetic field, with high working stability. Compared with the prior art, it can rotate axially and radially to brush teeth simultaneously, filling the gap in the market that electric toothbrushes have no axial telescopic motion except for radial left and right swings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0022] Figure 1 It is an exploded view of the overall structure of the present invention;

[0023] Figure 2 It is a schematic diagram of the overall structure of the present invention;

[0024] Figure 3 Right view of the present invention;

[0025] Figure 4 For the present invention Figure 3 A-A in ， Schematic cross-sectional structure diagram;

[0026] Figure 5 Front view of the present invention;

[0027] Figure 6 For the present invention Figure 5 B-B in ， Schematic cross-sectional structure diagram;

[0028] Figure 7 Schematic structure diagram of the rotor core of the present invention;

[0029] Figure 8 Schematic internal structure diagram of the motor of the present invention;

[0030] Figure 9 For the present invention Figure 8 C-C in ， Schematic cross-sectional structure diagram;

[0031] Figure 10 For the present invention Figure 8 D-D in ， Schematic cross-sectional structure diagram;

[0032] Figure 11 Front view of the distribution structure of the self-priming surface and non-self-priming surface of the present invention;

[0033] Figure 12 Left view of the distribution structure of the self-priming surface and non-self-priming surface of the present invention;

[0034] Figure 13 Left view of the magnetic steel polarity distribution structure in the present invention;

[0035] Figure 14 Front view of the magnetic steel polarity distribution structure in the present invention;

[0036] Figure 15 Schematic diagram of the magnetic steel distribution structure of the present invention.

[0037] Explanation of reference numerals:

[0038] 1 Motor housing, 2 Motor shaft branch, 3 End cover, 4 Bearing, 5 Transmission connecting shaft, 6 Insulation housing, 7 Commutator, 8 Brush needle, 9 Stator assembly, 10 Rotor assembly, 11 Stator skeleton, 12 Magnetic steel, 121 Self-priming surface, 122 Non-self-priming surface, 13 Placing groove, 14 Limiting frame, 15 Rotor core, 151 Rotor teeth, 152 Pole shoes, 16 Coil winding, 161 Coil one, 162 Coil two, 163 Coil three, 164 Coil four. DETAILED DESCRIPTION

[0039] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0040] The present invention provides Figures 1-15 A bidirectional magnetic suspension brushed motor device shown includes a motor housing 1, a motor shaft 2 and an end cover 3, wherein the end cover 3 is arranged at the bottom end of the motor housing 1, and shaft holes are opened at the axis centers of the motor housing 1 and the end cover 3, the motor shaft 2 is arranged between the two shaft holes, and bearings 4 are arranged at the connection between the motor shaft 2, the motor housing 1 and the end cover 3, the end of the motor shaft 2 away from the end cover 3 extends out of the motor housing 1, and a transmission connecting shaft 5 is arranged at the top of the motor shaft 2, and an insulating protective shell 6 is arranged on the side of the end cover 3 away from the motor housing 1, a commutator 7 is sleeved on the outer side of the bottom of the motor shaft 2, and two symmetrically distributed brush needles 8 are arranged on both sides of the bottom of the commutator 7, the cross-sectional shape of the brush needle 8 is set to be L-shaped, and the top and bottom ends of the brush needle 8 are respectively plugged with the commutator 7 and the end cover 3, and a transmission unit is arranged inside the motor housing 1, and the transmission unit consists of a stator assembly 9 and a rotor assembly 10, and the rotor assembly 10 is arranged inside the stator assembly 9;

[0041] The stator assembly 9 includes a stator frame 11 and a magnetic steel 12. The stator frame 11 is provided with placement grooves 13 on both sides. The magnetic steel 12 is arranged inside the placement grooves 13. The inner wall of the stator frame 11 is provided with limit frames 14 on both sides.

[0042] The rotor assembly 10 includes a rotor core 15 and a coil winding 16. The rotor core 15 is laminated and arranged outside the motor shaft 2. The rotor core 15 is composed of rotor teeth 151 and pole shoes 152. The rotor teeth 151 and the pole shoes 152 are integrated. The coil winding 16 is wound outside the rotor teeth 151.

[0043] The number of the placement slots 13 is set to four, the four placement slots 13 are symmetrically distributed about the bisector of the rotor core 15, the spacing angles between the four placement slots 13 are not equal, the four magnetic steels 12 are staggered in height, and the heights of two adjacent magnetic steels 12 are not equal, the magnetic steels 12 and the rotor core 15 form a self-absorption surface 121 and a non-self-absorption surface 122, and the area of ​​the self-absorption surface 121 is greater than the area of ​​the non-self-absorption surface 122;

[0044] The combination of the commutator 7 and the brush pins 8 provides a medium for introducing external circuit current into the rotor coil winding to generate a magnetic field.

[0045] Further, in the above technical solution, the motor shaft branch 2 is coaxially arranged with the transmission connecting shaft 5. A plugging groove is formed at the bottom end of the transmission connecting shaft 5, and the top end of the motor shaft branch 2 is arranged inside the plugging groove. The motor shaft branch 2 is in transmission connection with the transmission connecting shaft 5. On the one hand, the machining accuracy of the shaft is improved, and on the other hand, the production efficiency is improved. Different customers only need to replace different output shafts, and the motors can be stocked, which is easy to standardize.

[0046] Further, in the above technical solution, the number of the transmission units is set to one or more, and the preset values mentioned in the multiple transmission units are set to one or more.

[0047] Further, in the above technical solution, the cross-sectional shape of the motor housing 1 is set to be flat or circular. The end cover 3 and the stator skeleton 11 both match the inner contour of the motor housing 1, and the end cover 3 is riveted to the motor housing 1. The rotor core 15 matches the inner wall of the stator skeleton 11. The insulating housing 6 can protect the brush needle 8 from being deformed easily. After welding the wires, it is covered and then the connecting wires are led out, which also serves the purpose of insulation.

[0048] Further, in the above technical solution, the winding directions of the coil windings 16 on the rotor teeth 151 are the same. The two transmission units are electrically connected through coil taps. The tap wires of the four coil windings 16 are respectively set as coil one 161, coil two 162, coil three 163 and coil four 164. The head of the coil one 161 is connected to the tail of the coil two 162. The head of the coil three 163 is connected to the tail of the coil four 164. The heads of the coil two 162 and the coil four 164 are connected to one side of the commutator 7. Ears are provided on both sides at the top end of the commutator 7. The tail of the coil one 161 and the tail of the coil three 163 are connected to the ears of the commutator 7.

[0049] Further, in the above technical solution, the coil windings of the coil windings 16 are respectively set as upper and lower windings and left and right windings. The magnetic fields after the upper and lower windings are energized are the same, and the magnetic fields after the left and right windings are energized are opposite.

[0050] Further, in the above technical solution, the four magnetic steels 12 in the transmission unit are divided into two groups. The number of each group of magnetic steels 12 is set to two, and the polarities of the two magnetic steels 12 in each group are opposite. The upper and lower magnetic poles of the two groups of magnetic steels 12 correspond to the same;

[0051] Radially, since the rotor teeth attract the magnetic steel and the self-attracting surface has a larger area than the non-self-attracting surface, it can float radially; axially, also because the rotor core attracts the magnetic steel and the self-attracting surface has a larger area than the non-self-attracting surface, it can float axially; radially, even when the rotor swings to the maximum position angle, the area of the self-attracting surface is still larger than the non-self-attracting surface; axially, even when the rotor axially displaces to the maximum position, the area of the self-attracting surface is still larger than the non-self-attracting surface.

[0052] Furthermore, in the above technical solution, the brush pin 8 is electrically connected to an external power source, and the brush pin 8 is electrically connected to the coil winding 16 via the commutator 7 .

[0053] Furthermore, in the above technical solution, 3M insulating powder is coated on the surface of the rotor core 15 to provide insulation between the coil winding 16 and the rotor core 15 .

[0054] The bottom end of the motor housing 1 is riveted and sealed by the end cover 3, and is insulated and protected by the insulating shell 6. The bearing 4 is used relative to the stator assembly 9 to form a bidirectional magnetic levitation motor structure, so that the rotation of the motor shaft 2 is smoother, avoiding the wear of the motor shaft 2, and at the same time stabilizing the position of the motor shaft 2. At the same time, a pair of bearings 4 can make the front and rear ends of the motor shaft 2 more evenly stressed and stably installed. On the one hand, it provides a support position for the motor shaft 2, facilitating the compact installation and stable matching of the stator assembly 9 and the rotor assembly 10. On the other hand, it can also protect the internal stator assembly 9 and the rotor assembly 10 from as little pollution and influence as possible from the external environment, thereby ensuring continuous and stable power transmission of the motor shaft 2.

[0055] The specific implementation method is as follows: when the device is actually used, the external current is guided to the coil winding 16 through the commutator 7 and the brush needle 8 to energize the rotor core 15 to form a magnetic field. The magnetic steel 12 is located within the magnetic field. Since there are preset values ​​in the radial and axial directions, they interact with each other. The stators with the same polarity push the magnetic steels 12 with different polarities. The magnetic steels 12 with the same polarity are acted upon by the stator magnetic fields with different polarities, so that the magnetic steel 12 pushes the rotor core 15 to rotate and reciprocates up and down at the same time. Since the rotor core 15 is fixedly connected to the motor shaft 2, the motor shaft 2 is driven to rotate and reciprocate up and down at the same time. The coil winding 16 switches the current direction and controls the energization time through the external circuit, so that the rotor produces left and right up and down reciprocating motions. The movement of the rotor assembly 10 is In response to the movement of the motor shaft 2, the electromagnetic effect is used to realize the transmission of motion, and there is no need to install elastic structures such as torsion bars. On the one hand, this avoids the situation where the elastic structure is easily damaged during use, which shortens the service life of the motor. On the other hand, the motor per unit volume can transmit a larger torque, so the size of the motor can be reduced as much as possible while reaching the rated torque. When the device is applied to an electric toothbrush, the weight of the electric toothbrush can be reduced, and the upward and downward telescopic movement while swinging left and right is closer to the feeling of brushing teeth in daily life, and the cleaning effect is greatly improved. The power is transmitted through the electromagnetic structure, making the power transmission process more stable, and the combination of the commutator 7 and the brush needle 8 provides a transmission medium, which introduces the external circuit current into the rotor coil winding to generate a magnetic field, and the working stability is relatively high.

[0056] Working principle of the present invention:

[0057] Refer to the appended drawings of the specification Figures 1-14 When the coil winding 16 is energized, a magnetic field is formed at the rotor core 15. The permanent magnet 12 is located within the range of this magnetic field. Since both the radial and axial directions have preset values, they interact with each other. The stator with the same polarity pushes the anisotropic permanent magnet 12, and the permanent magnet 12 with the same polarity is subjected to the acting force of the anisotropic stator magnetic field, so that while the permanent magnet 12 pushes the rotor core 15 to rotate, it also makes the rotor core 15 move up and down reciprocally. Since the rotor core 15 is fixedly connected to the motor shaft branch 2, it further drives the motor shaft branch 2 to rotate while making an up and down reciprocating motion. The coil winding 16 switches the current direction and controls the energization time through an external circuit, so that the rotor generates a reciprocating motion in all directions (left, right, up, and down). The movement of the rotor assembly 10 corresponds to the movement of the motor shaft branch 2. The movement is transmitted relying on the electromagnetic effect, and there is no need to install an elastic structure such as a torsion bar. On the one hand, it avoids the situation that the elastic structure is easily damaged during use, resulting in a short service life of the motor. On the other hand, it enables the motor with a unit volume to transmit a larger value of torque.

[0058] Only some exemplary embodiments of the present invention have been described by way of illustration above. Without doubt, for those of ordinary skill in the art, various different ways can be used to modify the described embodiments without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the protection scope of the claims of the present invention.

Claims

1. A bidirectional magnetic levitation brushed motor device, comprising a motor housing (1), a motor shaft branch (2) and an end cover (3). Characterized in that: The end cover (3) is arranged at the bottom end of the motor housing (1). Axial holes are provided at the centers of the motor housing (1) and the end cover (3). The motor shaft branch (2) is arranged between the two axial holes. Bearings (4) are provided at the joints of the motor shaft branch (2) and the motor housing (1) and the end cover (3). One end of the motor shaft branch (2) away from the end cover (3) extends out of the motor housing (1), and a transmission connecting shaft (5) is provided at the top end of the motor shaft branch (2). An insulating housing (6) is provided on one side of the end cover (3) away from the motor housing (1). A commutator (7) is sleeved on the outer side of the bottom of the motor shaft branch (2). Two symmetrically distributed brush needles (8) are provided on both sides of the bottom of the commutator (7). The cross-sectional shape of the brush needle (8) is set as an L shape, and the top end and the bottom end of the brush needle (8) are respectively inserted into the commutator (7) and the end cover (3). A transmission unit is provided inside the motor housing (1). The transmission unit is composed of a stator assembly (9) and a rotor assembly (10), and the rotor assembly (10) is arranged inside the stator assembly (9); The stator assembly (9) includes a stator skeleton (11) and magnetic steel (12). Placing grooves (13) are provided on both sides of the stator skeleton (11). The magnetic steel (12) is arranged inside the placing grooves (13). Limiting frames (14) are provided on both sides of the inner wall of the stator skeleton (11); The rotor assembly (10) includes a rotor iron core (15) and a coil winding (16). The rotor iron core (15) is stacked on the outer side of the motor shaft branch (2). The rotor iron core (15) is composed of rotor teeth (151) and pole shoes (152), and the rotor teeth (151) and the pole shoes (152) are integrally arranged. The coil winding (16) is wound around the outer side of the rotor teeth (151); The number of the placing grooves (13) is set as four. The four placing grooves (13) are symmetrically distributed about the bisector of the rotor iron core (15). The spacing angles between the four placing grooves (13) are not equal. The heights of the four magnetic steels (12) are staggered, and the heights of two adjacent magnetic steels (12) are not equal. The magnetic steel (12) and the rotor iron core (15) form a self - absorbing surface (121) and a non - self - absorbing surface (122), and the area of the self - absorbing surface (121) is larger than the area of the non - self - absorbing surface (122); The energized coil winding (16) forms a magnetic field at the rotor core (15). The permanent magnet (12) is within the range of this magnetic field. The stator magnetic field with the same polarity pushes the anisotropic permanent magnets (12). The permanent magnets (12) with the same polarity are subjected to the acting force of the anisotropic stator magnetic field, so that while the permanent magnets (12) push the rotor core (15) to rotate, the rotor core (15) moves up and down reciprocally. Since the rotor core (15) is fixedly connected to the motor shaft branch (2), the motor shaft branch (2) is driven to rotate and move up and down reciprocally at the same time. The coil winding (16) switches the current direction and controls the energization time through an external circuit, so that the rotor core (15) generates a reciprocating motion in all directions (left, right, up, and down).

2. A two-way magnetic levitation brushed motor device according to claim 1, characterized in that: The motor shaft branch (2) is coaxially arranged with the transmission connecting shaft (5). A plug-in groove is provided at the bottom end of the transmission connecting shaft (5). The top end of the motor shaft branch (2) is arranged inside the plug-in groove, and the motor shaft branch (2) is in transmission connection with the transmission connecting shaft (5).

3. A two-way magnetic levitation brushed motor device according to claim 1, characterized in that: The number of the transmission units is set to one or more, and the preset values mentioned in the multiple transmission units are set to one or more.

4. A two-way magnetic levitation brushed motor device according to claim 1, characterized in that: The cross-sectional shape of the motor housing (1) is set to be flat or circular. The end cover (3) and the stator skeleton (11) both match the inner contour of the motor housing (1), and the end cover (3) is riveted to the motor housing (1). The rotor core (15) matches the inner wall of the stator skeleton (11).

5. A two-way magnetic levitation brushed motor device according to claim 1, characterized in that: The coil winding (16) has the same winding direction on the rotor teeth (151). The two transmission units are electrically connected through a coil tap. The tap wires of the four coil windings (16) are respectively set as coil one (161), coil two (162), coil three (163) and coil four (164). The head of coil one (161) is connected to the tail of coil two (162). The head of coil three (163) is connected to the tail of coil four (164). The heads of coil two (162) and coil four (164) are connected to one side of the commutator (7). There are ears on both sides of the top end of the commutator (7). The tail of coil one (161) and the tail of coil three (163) are connected to the ears of the commutator (7).

6. A two-way magnetic levitation brushed motor device according to claim 1, characterized in that: The coil windings (16) are respectively set as upper and lower windings and left and right windings. The magnetic fields after the upper and lower windings are energized are the same, and the magnetic fields after the left and right windings are energized are opposite.

7. A two-way magnetic levitation brushed motor device according to claim 1, characterized in that: In the transmission unit, the four permanent magnets (12) are divided into two groups, the number of permanent magnets (12) in each group is set to two, and the polarities of the two permanent magnets (12) in each group are opposite, and the upper and lower magnetic poles of the two groups of permanent magnets (12) correspond to the same.

8. A two-way magnetic levitation brushed motor device according to claim 1, characterized in that: The brush needle (8) is electrically connected to an external power supply, and the brush needle (8) is electrically connected to the coil winding (16) through a commutator (7).

9. A two-way magnetic levitation brushed motor device according to claim 1, characterized in that: The surface of the rotor core (15) is coated with 3M insulating powder.

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