Brushless motor

Abstract

The application relates to the motor technology field and provides a brushless motor which comprises a stator and a rotor spaced from the stator, the stator drives the rotor to rotate; the stator comprises a framework and a coil sleeved and fixed to the framework; the framework comprises a framework body and a plurality of bosses, two adjacent bosses and the framework body form a coil winding groove for accommodating the coil, the coil winding groove is multiple, the rotor comprises a fixing member in the form of a ring, a plurality of first magnetic steels and a plurality of second magnetic steels, the circumferential width of the first coil winding groove along the framework body from the opening end of the outer ring is greater than or equal to the circumferential width of the first side along the framework body from the side of the outer ring, and / or the circumferential width of the second coil winding groove along the framework body from the opening end of the inner ring is greater than or equal to the circumferential width of the second side along the framework body from the side of the inner ring. Compared with the related art, the rotating torque of the application is greatly enhanced.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and more particularly to a brushless motor. Background Technology

[0002] With the development of electronic technology, portable consumer electronics products are becoming increasingly popular, such as mobile phones, handheld game consoles, navigation devices, and handheld multimedia entertainment devices. These electronic products generally use vibration motors for system feedback, such as call alerts, message alerts, navigation prompts, and vibration feedback for game consoles. Such widespread application requires motors with excellent performance and long service life.

[0003] The brushless motor of the related technology includes a stator and a rotor. The stator drives the rotor to rotate, thereby realizing the rotation of the motor. The stator includes a frame, a connecting part extending from the outer periphery of the frame, and a coil sleeved and fixed to the connecting part; the rotor includes magnets arranged around the frame, with the magnets spaced apart from each other. The frame is magnetized by the coil, so that the frame and the magnets generate a mutual rotational torque to drive the rotor to rotate.

[0004] However, in brushless motors of related technologies, the rotor is driven to rotate by the mutual rotational torque generated by the frame and magnets through the electromagnetic coil. The rotational torque is singular and the driving effect is poor.

[0005] Therefore, it is necessary to provide a new brushless motor to solve the above problems. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a brushless motor in which magnets are set on the inner and outer sides of the coil to provide a magnetic field, and the energized coil generates a rotational torque in the magnetic field. The magnetized frame also generates a rotational torque in the same direction as the coil, so as to greatly enhance the rotational torque.

[0007] To solve the above-mentioned technical problems, the present invention provides a brushless motor, which includes a stator and a rotor spaced apart from the stator, wherein the stator drives the rotor to rotate;

[0008] The stator includes a frame and coils sleeved and fixed to the frame;

[0009] The skeleton includes an annular skeleton body with a first through hole and a plurality of protrusions extending from the skeleton body away from the skeleton body. The plurality of protrusions are arranged at intervals along the circumference of the skeleton body. Two adjacent protrusions and the skeleton body form a winding groove for receiving the coil. The winding groove includes a plurality of grooves and is arranged at intervals along the circumference of the skeleton body. The coil includes a plurality of coils, and one coil is wound in each winding groove. The coil surrounds the skeleton body and passes through the first through hole.

[0010] The rotor includes a ring-shaped fixing member, and a plurality of first magnets and a plurality of second magnets fixed to the fixing member. The plurality of first magnets are arranged circumferentially along the fixing member to form an outer ring, and the plurality of second magnets are arranged circumferentially along the fixing member to form an inner ring. The outer ring surrounds the inner ring, such that the first magnets and second magnets are opposite to each other and spaced apart. The coils are spaced between the outer ring and the inner ring. When the coils are energized, they drive the first magnets and second magnets to rotate the fixing member.

[0011] The winding groove includes a first winding groove facing the outer ring and a second winding groove facing the inner ring; the coil includes a first side facing the outer ring and a second side facing the inner ring.

[0012] The circumferential width of the opening end of the first winding groove facing the outer ring along the skeleton body is greater than or equal to the circumferential width of the side of the first side facing the outer ring along the skeleton body.

[0013] And / or, the circumferential width of the opening end of the second winding groove facing the inner ring along the skeleton body is greater than or equal to the circumferential width of the side of the second side facing the inner ring along the skeleton body.

[0014] Preferably, the stator further includes a cover plate, the frame is fixed to the cover plate, the winding groove further includes a third winding groove facing the cover plate and a fourth winding groove away from the cover plate; the coil further includes a third side facing the cover plate and a fourth side away from the cover plate.

[0015] Along the axial direction of the skeleton body, the circumferential width of the third winding groove facing the opening end of the cover plate along the skeleton body is greater than or equal to the circumferential width of the third side facing the cover plate along the skeleton body.

[0016] And / or, the circumferential width of the fourth winding groove at the opening end away from the cover plate along the skeleton body is greater than or equal to the circumferential width of the fourth side away from the cover plate along the skeleton body.

[0017] Preferably, when each coil is wound in the corresponding winding groove, along the axial direction of the skeleton body, the boss includes a first outer surface fixed to the cover plate and a second outer surface facing away from the cover plate. The axial distance from the first outer surface to the skeleton body is greater than or equal to the axial distance from the third side surface to the skeleton body, and the axial distance from the second outer surface to the skeleton body is greater than or equal to the axial distance from the fourth side surface to the skeleton body.

[0018] Preferably, when each coil is wound in the corresponding winding groove, along the radial direction of the skeleton body, the boss further includes a third outer surface facing the outer ring and a fourth outer surface facing the inner ring. The radial distance from the third outer surface to the skeleton body is greater than or equal to the radial distance from the first side surface to the skeleton body, and the radial distance from the fourth outer surface to the skeleton body is greater than or equal to the radial distance from the second side surface to the skeleton body.

[0019] Preferably, both the first magnet and the second magnet are magnetized radially along the rotor. Along the circumference of the outer ring, the magnetic poles of the plurality of first magnets are arranged alternately with N and S poles. Along the circumference of the inner ring, the magnetic poles of the plurality of second magnets are arranged alternately with N and S poles. The magnetization direction of the first magnet is opposite to that of the corresponding second magnet.

[0020] Preferably, the stator further includes an annular cover plate and a first rotating portion protruding from the inner circumferential side of the cover plate; the frame is fixed to the cover plate, the frame is arranged around the first rotating portion and spaced apart from the first rotating portion, and the fixing member is sleeved on the first rotating portion and forms a rotatable connection with it.

[0021] Preferably, the fastener includes an annular fastener body, a second rotating portion formed by bending and extending from the inner circumference of the fastener body toward the cover plate, and a fastening portion formed by bending and extending from the outer circumference of the fastener body toward the cover plate; the second rotating portion is sleeved on the first rotating portion and forms a rotatable connection with the first rotating portion; the first magnet is fixed to the inner circumference of the fastening portion, and the second magnet is sleeved and fixed to the outer circumference of the second rotating portion.

[0022] Preferably, the multiple coils are arranged at equal intervals along the circumference of the skeleton body and are defined as multiple groups, each group including phase A coil, phase B coil and phase C coil in sequence.

[0023] Preferably, each coil is individually wound and has an inlet and an outlet; the brushless motor further includes a circuit board fixed to the side of the cover plate near the coil, and both the inlet and outlet are electrically connected to the circuit board.

[0024] Preferably, the circuit board includes an annular circuit board body, a connecting portion extending outward from one side of the circuit board body, and a plurality of second through holes formed through the circuit board body; the boss passes through the second through holes and is fixedly connected to the cover plate, and the connecting portion is used to connect to an external power source.

[0025] Preferably, the orthographic projection of each coil toward the cover plate falls within the range between two adjacent second through holes.

[0026] Preferably, the brushless motor further includes a first bearing and a second bearing; the inner circumferential sides of the first bearing and the second bearing are respectively sleeved and fixed to the first rotating part, and the outer circumferential sides of the first bearing and the second bearing are respectively fixed to the side of the second rotating part near the first rotating part; the first bearing and the second bearing are spaced apart from each other along the axial direction of the rotor.

[0027] Preferably, the skeleton is made of a soft magnetic material.

[0028] Preferably, the brushless motor further includes a plurality of third magnets, which are fixed to the side of the fixing body near the cover plate and arranged at intervals along the circumference of the fixing body. The third magnets are spaced apart from the coil. Each third magnet is magnetized along the axial direction of the rotor. The magnetic poles of the plurality of third magnets are arranged with alternating N and S poles. Adjacent first magnets, second magnets and third magnets are all magnetized toward or away from the coil.

[0029] Compared with related technologies, in the brushless motor of the present invention, a fixed coil is sleeved on the frame, and two adjacent bosses of the frame and the frame body form a winding groove for receiving the coil. Multiple winding grooves are arranged at intervals along the circumference of the frame body. Multiple coils are included, and one coil is wound in each winding groove. Multiple first magnets of the rotor are arranged along the circumference of the fixing member to form an outer ring, and multiple second magnets are arranged along the circumference of the fixing member to form an inner ring. The outer ring surrounds the inner ring, such that the first and second magnets are opposite to each other and spaced apart. The coils are spaced between the outer and inner rings. When the coils are energized, they drive the first and second magnets to rotate the fixing member. The winding grooves include a first winding groove facing the outer ring and a second winding groove facing the inner ring. The coil wraps... The frame includes a first side facing the outer ring and a second side facing the inner ring; the circumferential width of the opening end of the first winding groove facing the outer ring along the frame body is greater than or equal to the circumferential width of the first side facing the outer ring along the frame body, and / or, the circumferential width of the opening end of the second winding groove facing the inner ring along the frame body is greater than or equal to the circumferential width of the second side facing the inner ring along the frame body; thus, by setting an indefinite number of winding grooves in the frame to place the coil, and placing the first magnet and the second magnet on the outside and inside of the coil respectively to provide a magnetic field, the coil magnetizes the frame after being energized, and the energized coil generates a rotational torque in the magnetic field. The magnetized frame also generates a rotational torque in the same direction as the coil, which greatly enhances the rotational torque and improves the motor drive effect. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0031] Figure 1 This is a three-dimensional structural diagram of the brushless motor provided in Embodiment 1 of the present invention;

[0032] Figure 2 This is a schematic diagram of the overall exploded structure of the brushless motor provided in Embodiment 1 of the present invention;

[0033] Figure 3 For along Figure 1 Cross-sectional view along line AA;

[0034] Figure 4 This is a schematic diagram of the internal structure of the brushless motor provided in Embodiment 1 of the present invention;

[0035] Figure 5 The magnetic field cloud diagram of the first and second rotational torques of the brushless motor provided in Embodiment 1 of the present invention;

[0036] Figure 6 This is a magnetic field cloud diagram of the first rotational torque of the brushless motor provided in Embodiment 1 of the present invention;

[0037] Figure 7 This is a three-dimensional exploded view of the stator of the brushless motor provided in Embodiment 1 of the present invention;

[0038] Figure 8 This is a bottom view of the stator of the brushless motor provided in Embodiment 1 of the present invention;

[0039] Figure 9 This is a three-dimensional structural diagram of the brushless motor provided in Embodiment 2 of the present invention;

[0040] Figure 10 This is a schematic diagram of the overall exploded structure of the brushless motor provided in Embodiment 2 of the present invention;

[0041] Figure 11 For along Figure 9 Cross-sectional view along line BB.

[0042] In the figure, 100 is the brushless motor of Embodiment 1, 1 is the stator, 11 is the cover plate, 12 is the first rotating part, 13 is the frame, 131 is the frame body, 132 is the winding groove, 1321 is the first winding groove, 1322 is the second winding groove, 1323 is the third winding groove, 1324 is the fourth winding groove, 133 is the boss, 1331 is the first outer surface, 1332 is the second outer surface, 1333 is the third outer surface, 1334 is the fourth outer surface, and 134 is the first through hole. 14. Coil; 141. First side; 142. Second side; 143. Third side; 144. Fourth side; 2. Rotor; 21. Fixing member; 211. Fixing member body; 212. Second rotating part; 213. Fixing part; 2131. Protrusion; 22. First magnet; 221. Outer ring; 23. Second magnet; 231. Inner ring; 3. Circuit board; 31. Circuit board body; 32. Connecting part; 33. Second through hole; 4. First bearing; 5. Second bearing;

[0043] 200. Brushless motor of Example 2; 20. Third magnet. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] Example 1

[0046] Please see Figures 1-8 As shown, the present invention provides a brushless motor 100, which includes a stator 1 and a rotor 2 spaced apart from the stator 1, wherein the stator 1 drives the rotor 2 to rotate.

[0047] The stator 1 includes a frame 13 and a coil 14 fitted and fixed to the frame 13. The frame 13 facilitates the installation and fixing of the coil 14. When the coil 14 is energized, the frame 13 is magnetized, and the overall magnetic field strength is enhanced.

[0048] The skeleton 13 includes an annular skeleton body 131 with a first through hole 134 and a plurality of protrusions 133 extending from the skeleton body 131 in a direction away from the skeleton body 131. The plurality of protrusions 133 are arranged at intervals along the circumference of the skeleton body 131. Two adjacent protrusions 133 and the skeleton body 131 form a winding groove 132 for receiving the coil 14. The winding groove 132 includes a plurality of grooves and is arranged at intervals along the circumference of the skeleton body 131. The coil 14 includes a plurality of grooves, and one coil 14 is wound in each winding groove 132. The coil 14 surrounds the skeleton body 131 and passes through the first through hole 134.

[0049] The rotor 2 includes a ring-shaped fixing member 21, and a plurality of first magnets 22 and a plurality of second magnets 23 fixed to the fixing member 21. The plurality of first magnets 22 are arranged circumferentially around the fixing member 21 to form an outer ring 221, and the plurality of second magnets 23 are arranged circumferentially around the fixing member 21 to form an inner ring 231. The outer ring 221 surrounds the inner ring 231, such that the first magnets 22 and the second magnets 23 are opposite to each other and spaced apart. A coil 14 is spaced between the outer ring 221 and the inner ring 231. When the coil 14 is energized, it drives the first magnets 22 and the second magnets 23 to rotate the fixing member 21. When the coil 14 is energized, it generates a first rotational torque T1 in the magnetic field formed by the first magnets 22 and the second magnets 23. The coil 14 magnetizes the frame 13, and the magnetized frame 13 also generates a second rotational torque T2 in the same direction as the coil 14; under the combined action of the first rotational torque T1 and the second rotational torque T2, the motor torque will be greatly increased. Optionally, the fixing member 21 can be made of magnetic material.

[0050] The winding groove 132 includes a first winding groove 1321 facing the outer ring 221 and a second winding groove 1322 facing the inner ring 231; the coil 14 includes a first side surface 141 facing the outer ring 221 and a second side surface 142 facing the inner ring 231.

[0051] The opening end of the first winding groove 1321 facing the outer ring 221 has a circumferential width a along the skeleton body 131 that is greater than or equal to the circumferential width a1 of the first side surface 141 facing the outer ring 221 along the skeleton body 131, and / or, the opening end of the second winding groove 1322 facing the inner ring 231 has a circumferential width b along the skeleton body 131 that is greater than or equal to the circumferential width b1 of the second side surface 142 facing the inner ring 231 along the skeleton body 131. The first side surface 141 and the second side surface 142 are respectively disposed within the first winding groove 1321 and the second winding groove 1322, and the outer sides of the first side surface 141 and the second side surface 142 do not protrude beyond the outer periphery of the boss 133, so that the magnetic lines of force pass through the coil 14 unobstructed, which can increase the rotational torque of the coil 14, while reducing the torque of the winding groove 132 and improving motor noise. At the same time, the coil 14 does not extend beyond the outer surface of the frame 13, and the coil 14 can be completely attached to the frame 13. The second rotational torque T2 generated by the magnetization of the frame 13 will be stronger, and with the surface protection of the frame 13, the coil 14 is less likely to be scratched by the outside world, which can also play a protective role.

[0052] In this embodiment, the stator 1 further includes a cover plate 11, the frame 13 is fixed to the cover plate 11, the winding groove 132 further includes a third winding groove 1323 facing the cover plate 11 and a fourth winding groove 1324 away from the cover plate 11; the coil 14 further includes a third side surface 143 facing the cover plate 11 and a fourth side surface 144 away from the cover plate 11. Along the axial direction of the frame body 131, the circumferential width c of the third winding groove 1323 facing the cover plate 11 along the frame body 131 is greater than or equal to the circumferential width c1 of the third side surface 143 facing the cover plate 11 along the frame body 131, and / or, the circumferential width d of the fourth winding groove 1324 away from the cover plate 11 along the frame body 131 is greater than or equal to the circumferential width d1 of the fourth side surface 144 away from the cover plate 11 along the frame body 131.

[0053] In this embodiment, when each coil 14 is wound in the corresponding winding groove 132, along the axial direction of the skeleton body 131, the boss 133 includes a first outer surface 1331 fixed to the cover plate 11 and a second outer surface 1332 facing away from the cover plate 11. The axial distance from the first outer surface 1331 to the skeleton body 131 is greater than or equal to the axial distance from the third side surface 143 to the skeleton body 131, and the axial distance from the second outer surface 1332 to the skeleton body 131 is greater than or equal to the axial distance from the fourth side surface 144 to the skeleton body 131.

[0054] In this embodiment, when each coil 14 is wound in the corresponding winding groove 132, along the radial direction of the skeleton body 131, the boss 133 further includes a third outer surface 1333 facing the outer ring 221 and a fourth outer surface 1334 facing the inner ring 231. The radial distance from the third outer surface 1333 to the skeleton body 131 is greater than or equal to the radial distance from the first side surface 141 to the skeleton body 131, and the radial distance from the fourth outer surface 1334 to the skeleton body 131 is greater than or equal to the radial distance from the second side surface 142 to the skeleton body 131. This ensures that the outer surface of the entire coil 14 does not protrude beyond the outer surface of the boss 133, providing a good protective effect.

[0055] In this embodiment, both the first magnet 22 and the second magnet 23 are magnetized radially along the rotor 2. Along the circumference of the outer ring 221, the magnetic poles of the first magnet 22 are arranged in a ring with alternating N and S poles, and the magnetic poles of the second magnet 23 are also arranged in a ring with alternating N and S poles. Along the circumference of the inner ring 231, both the first magnet 22 and the second magnet 23 are magnetized radially along the rotor 2, with the magnetization direction of the first magnet 22 opposite to that of the second magnet 23, thus increasing the magnetic field strength. The magnetic field strength is greatest at the intersection of the N pole of the first magnet 22 and the S pole of the adjacent second magnet 23, forming a loop with the frame 13. The first magnet 22 and the second magnet 23 generate a second electromagnetic rotational torque T2 with the frame 13. Under the combined action of the first rotational torque T1 and the second rotational torque T2, the motor torque is greatly increased. Specifically, the S pole magnetizes the N pole.

[0056] In this embodiment, the frame 13 can be fixed to the cover plate 11 by welding, gluing, or other fixing methods. The fixing effect is good.

[0057] In this embodiment, the stator 1 further includes an annular cover plate 11 and a first rotating portion 12 extending from the inner circumferential side of the cover plate 11; the frame 13 is fixed to the cover plate 11, the frame 13 is arranged around the first rotating portion 12 and spaced apart from the first rotating portion 12, and the fixing member 21 is sleeved on the first rotating portion 12 and forms a rotatable connection with it. The cover plate 11 is used to support and fix the frame 13.

[0058] In this embodiment, the fixing member 21 includes a ring-shaped fixing member body 211, a second rotating part 212 formed by bending and extending from the inner circumference of the fixing member body 211 towards the cover plate 11, and a fixing part 213 formed by bending and extending from the outer circumference of the fixing member body 211 towards the cover plate 11. The second rotating part 212 is sleeved on the first rotating part 12 and forms a rotatable connection with the first rotating part 12. The first magnet 22 is fixed to the inner circumference of the fixing part 213, and the second magnet 23 is sleeved and fixed to the outer circumference of the second rotating part 212. Through the rotatable connection between the second rotating part 212 and the first rotating part 12, after the coil 14 is energized, it drives the first magnet 22 and the second magnet 23 to drive the second rotating part 212 to rotate, thereby achieving a motor drive effect.

[0059] In this embodiment, the brushless motor 100 further includes an annular protrusion 2131 formed by bending outward radially from one end of the fixing portion 213 near the cover plate 11; the protrusion 2131 is spaced apart from the cover plate 11, and the outer peripheral side of the protrusion 2131 is flush with the outer peripheral side of the cover plate 11. This makes the brushless motor 100 small overall, suitable for use in micro motors.

[0060] In this embodiment, multiple coils 14 are arranged at equal intervals along the circumference of the frame body 131 and are sequentially defined as multiple groups; each group sequentially includes an A-phase coil, a B-phase coil, and a C-phase coil. The phase difference between the currents of the A-phase coil and the B-phase coil is 120 degrees, and the phase difference between the currents of the B-phase coil and the C-phase coil is also 120 degrees. The individually wound coils 14 are energized with periodically changing currents, such as sinusoidal currents or square wave currents. For example, if the current phase of the A-phase coil is 0 degrees, then the current phase of the B-phase coil is 120 degrees, and the current phase of the C-phase coil is 240 degrees, etc.

[0061] In this embodiment, each coil 14 is individually wound and has an input end and an output end. The brushless motor 100 also includes a circuit board 3 fixed to the side of the cover plate 11 near the coil 14, and both the input end and the output end are electrically connected to the circuit board 3. By soldering the input end and the output end of the coil 14 onto the circuit board 3 (FPC), each coil 14 is individually electrically connected through the circuit board 3, and there are no flying wires between the coils 14, thus preventing interference to the outside world.

[0062] In this embodiment, the circuit board 3 includes an annular circuit board body 31, a connecting portion 32 extending outward from one side of the circuit board body 31, and a plurality of second through holes 33 forming through the circuit board body 31. The boss 133 passes through the second through holes 33 and is fixedly connected to the cover plate 11, and the connecting portion 32 is used to connect to an external power source.

[0063] In this embodiment, the orthographic projection of each coil 14 toward the cover plate 11 falls within the area formed between two adjacent second through holes 33.

[0064] In this embodiment, the brushless motor 100 further includes a first bearing 4 and a second bearing 5; the inner circumferential sides of the first bearing 4 and the second bearing 5 are respectively sleeved and fixed to the first rotating part 12, and the outer circumferential sides of the first bearing 4 and the second bearing 5 are respectively fixed to the side of the second rotating part 212 near the first rotating part 12; the first bearing 4 and the second bearing 5 are spaced apart from each other along the axial direction of the rotor 2. The connection between the first bearing 4 and the second bearing 5 can provide good support and drag reduction, resulting in good rotation of the rotor 2.

[0065] In this embodiment, the skeleton 13 is made of soft magnetic material.

[0066] In this embodiment, the soft magnetic material is any one of SPCD (Steel Plate Cold Rolled for Drawing), iron-cobalt alloy, amorphous, nanocrystalline, and silicon steel.

[0067] In this embodiment, the number of coils 14 corresponds one-to-one with the number of winding slots 132 on the frame 13 where the coils 14 are placed, and is called the number of slots. The number of slots is not required. The first magnet 22 and the second magnet 23 are both multi-stage magnets or multiple spliced ​​magnets. The number of magnetic poles of the magnet is called the pole number. The pole number and the number of slots together are called the slot pole number. The slot pole number needs to be consistent.

[0068] Example 2

[0069] Please see Figures 9-11As shown, this embodiment of the invention also provides a brushless motor 200. This second embodiment is basically the same in structure as the first embodiment; the difference is that in this embodiment, the brushless motor further includes a plurality of third magnets 20. The third magnets 20 are fixed to the side of the fixing body 211 near the cover plate 11 and are arranged at intervals along the circumference of the fixing body 211. The third magnets 20 are spaced apart from the coil 14. Each third magnet 20 is magnetized along the axial direction of the rotor 2, and the magnetic poles of the plurality of third magnets 20 are arranged alternately with N and S poles. By adding a third magnet 20 to the top of the coil 14, the magnetic pole direction of the third magnet 20 is similar to that of the second magnet 23, pointing inward or outward at the same time. This addition of the third magnet 20 makes the coil 14 and the frame 133 surface subjected to force, and the rotational torque of the rotor 2 is increased by 20%, thereby generating a stronger rotational torque. Optionally, the number of third magnets 20 is the same as that of the first magnets 22 and the second magnets 23. The adjacent first magnet 22, second magnet 23, and third magnet 20 are all magnetized in a direction facing or away from the coil 14. The driving effect is good. Compared with related technologies, in the brushless motor of the present invention, by mounting a fixed coil on the frame, two adjacent bosses of the frame and the frame body form a winding groove for receiving the coil. Multiple winding grooves are arranged at intervals along the circumference of the frame body. Multiple coils are included, with one coil wound in each winding groove. Multiple first magnets of the rotor are arranged along the circumference of the fixing member to form an outer ring, and multiple second magnets are arranged along the circumference of the fixing member to form an inner ring. The outer ring surrounds the inner ring, such that the first and second magnets are opposite to each other and spaced apart. The coils are spaced between the outer and inner rings. When the coils are energized, they drive the first and second magnets to rotate the fixing member. The winding grooves include a first winding groove facing the outer ring and a second winding groove facing the inner ring. The coil wraps... The frame includes a first side facing the outer ring and a second side facing the inner ring; the circumferential width of the opening end of the first winding groove facing the outer ring along the frame body is greater than or equal to the circumferential width of the first side facing the outer ring along the frame body, and / or, the circumferential width of the opening end of the second winding groove facing the inner ring along the frame body is greater than or equal to the circumferential width of the second side facing the inner ring along the frame body; thus, by setting an indefinite number of winding grooves in the frame to place the coil, and placing the first magnet and the second magnet on the outside and inside of the coil respectively to provide a magnetic field, the coil magnetizes the frame after being energized, and the energized coil generates a rotational torque in the magnetic field. The magnetized frame also generates a rotational torque in the same direction as the coil, which greatly enhances the rotational torque and improves the motor drive effect.

[0070] The above description is merely an embodiment of the present invention. It should be noted that those skilled in the art can make improvements without departing from the inventive concept of the present invention, but these improvements all fall within the protection scope of the present invention.

Claims

1. A brushless motor comprising a stator and a rotor spaced apart from the stator, the stator driving the rotor to rotate; characterized in that, The stator includes a frame and coils sleeved and fixed to the frame; The skeleton includes an annular skeleton body with a first through hole and a plurality of protrusions extending from the skeleton body away from the skeleton body. The plurality of protrusions are arranged at intervals along the circumference of the skeleton body. Two adjacent protrusions and the skeleton body form a winding groove for receiving the coil. The winding groove includes a plurality of grooves and is arranged at intervals along the circumference of the skeleton body. The coil includes a plurality of coils, and one coil is wound in each winding groove. The coil surrounds the skeleton body and passes through the first through hole. The rotor includes a ring-shaped fixing member, and a plurality of first magnets and a plurality of second magnets fixed to the fixing member. The plurality of first magnets are arranged circumferentially along the fixing member to form an outer ring, and the plurality of second magnets are arranged circumferentially along the fixing member to form an inner ring. The outer ring surrounds the inner ring, such that the first magnets and second magnets are opposite to each other and spaced apart. The coils are spaced between the outer ring and the inner ring. When the coils are energized, they drive the first magnets and second magnets to rotate the fixing member. The winding groove includes a first winding groove facing the outer ring and a second winding groove facing the inner ring; the coil includes a first side facing the outer ring and a second side facing the inner ring. The circumferential width of the opening end of the first winding groove facing the outer ring along the skeleton body is greater than or equal to the circumferential width of the side of the first side facing the outer ring along the skeleton body. And / or, the circumferential width of the opening end of the second winding groove facing the inner ring along the skeleton body is greater than or equal to the circumferential width of the side of the second side facing the inner ring along the skeleton body.

2. The brushless motor according to claim 1, characterized in that, The stator further includes a cover plate, the frame is fixed to the cover plate, the winding groove further includes a third winding groove facing the cover plate and a fourth winding groove away from the cover plate; the coil further includes a third side facing the cover plate and a fourth side away from the cover plate. Along the axial direction of the skeleton body, the circumferential width of the third winding groove facing the opening end of the cover plate along the skeleton body is greater than or equal to the circumferential width of the third side facing the cover plate along the skeleton body. And / or, the circumferential width of the fourth winding groove at the opening end away from the cover plate along the skeleton body is greater than or equal to the circumferential width of the fourth side away from the cover plate along the skeleton body.

3. The brushless motor according to claim 2, characterized in that, When each coil is wound in the corresponding winding groove, along the axial direction of the skeleton body, the boss includes a first outer surface fixed to the cover plate and a second outer surface facing away from the cover plate. The axial distance from the first outer surface to the skeleton body is greater than or equal to the axial distance from the third side surface to the skeleton body, and the axial distance from the second outer surface to the skeleton body is greater than or equal to the axial distance from the fourth side surface to the skeleton body.

4. The brushless motor according to claim 3, characterized in that, When each coil is wound in the corresponding winding groove, along the radial direction of the skeleton body, the boss further includes a third outer surface facing the outer ring and a fourth outer surface facing the inner ring. The radial distance from the third outer surface to the skeleton body is greater than or equal to the radial distance from the first side surface to the skeleton body, and the radial distance from the fourth outer surface to the skeleton body is greater than or equal to the radial distance from the second side surface to the skeleton body.

5. The brushless motor according to claim 1, characterized in that, Both the first magnet and the second magnet are magnetized radially along the rotor. Along the circumference of the outer ring, the magnetic poles of the first magnet are arranged alternately with N and S poles. Along the circumference of the inner ring, the magnetic poles of the second magnet are arranged alternately with N and S poles. The magnetization direction of the first magnet is opposite to that of the corresponding second magnet.

6. The brushless motor according to claim 5, characterized in that, The stator further includes an annular cover plate and a first rotating portion protruding from the inner circumferential side of the cover plate; the frame is fixed to the cover plate, the frame is arranged around the first rotating portion and spaced apart from the first rotating portion, and the fastener is sleeved on the first rotating portion and forms a rotatable connection with it.

7. The brushless motor according to claim 6, characterized in that, The fastener includes a ring-shaped fastener body, a second rotating portion formed by bending and extending from the inner circumference of the fastener body toward the cover plate, and a fixing portion formed by bending and extending from the outer circumference of the fastener body toward the cover plate; the second rotating portion is sleeved on the first rotating portion and forms a rotatable connection with the first rotating portion; the first magnet is fixed on the inner circumference of the fixing portion, and the second magnet is sleeved and fixed on the outer circumference of the second rotating portion.

8. The brushless motor according to claim 1, characterized in that, The multiple coils are arranged at equal intervals along the circumference of the skeleton body and are defined as multiple groups in sequence, each group including phase A coil, phase B coil and phase C coil in sequence.

9. The brushless motor according to claim 6, characterized in that, Each of the coils is individually wound and has an inlet and an outlet; the brushless motor also includes a circuit board fixed to the side of the cover plate near the coil, and both the inlet and outlet are electrically connected to the circuit board.

10. The brushless motor according to claim 9, characterized in that, The circuit board includes a ring-shaped circuit board body, a connecting portion extending outward from one side of the circuit board body, and a plurality of second through holes formed through the circuit board body; the boss passes through the second through holes and is fixedly connected to the cover plate, and the connecting portion is used to connect to an external power source.

11. The brushless motor according to claim 10, characterized in that, The orthographic projection of each coil toward the cover plate falls within the range between two adjacent second through holes.

12. The brushless motor according to claim 7, characterized in that, The brushless motor further includes a first bearing and a second bearing; the inner circumferences of the first bearing and the second bearing are respectively sleeved and fixed to the first rotating part, and the outer circumferences of the first bearing and the second bearing are respectively fixed to the side of the second rotating part near the first rotating part; the first bearing and the second bearing are spaced apart from each other along the axial direction of the rotor.

13. The brushless motor according to claim 1, characterized in that, The skeleton is made of soft magnetic material.

14. The brushless motor according to claim 7, characterized in that, The brushless motor also includes a plurality of third magnets, which are fixed to the side of the fixing body near the cover plate and arranged at intervals along the circumference of the fixing body. The third magnets are spaced apart from the coil. Each third magnet is magnetized along the axial direction of the rotor. The magnetic poles of the plurality of third magnets are arranged in an alternating N and S pole configuration. Adjacent first magnets, second magnets, and third magnets are all magnetized toward or away from the coil.

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