Magnetic pole fixing and limiting structure for surface-mounted permanent magnet motor

Abstract

The magnetic pole fixing and limiting structure comprises a stator and a rotor, the rotor is located in the stator, an air gap is formed between the rotor and the stator, a plurality of permanent magnets are arranged on the outer side of the rotor in the circumferential direction, the permanent magnets are parallel to the axis of the rotor, the rotor is provided with installation grooves corresponding to the permanent magnets, and the installation grooves correspond to the permanent magnets. The permanent magnets are inserted into the mounting grooves, the inner walls of the mounting grooves are evenly covered with magnetic steel glue, the rotor adheres and fixes the permanent magnets through the magnetic steel glue, the rotor is provided with two sets of positioning discs in the axial direction, all the permanent magnets are located between the two positioning discs, the positioning discs are provided with fixing screws, and the fixing screws penetrate through the positioning discs to be in threaded connection with the rotor. The two axial ends of the permanent magnet are provided with positioning parts, the end faces, away from the rotor axis, of the positioning parts are arranged to be abutting faces, the abutting faces gradually approach the rotor axis in the direction away from the permanent magnet, the side, close to the permanent magnet, of the positioning disc is fixedly provided with a positioning ring in the circumferential direction, and the ends, away from the permanent magnet, of the positioning parts are located in the positioning ring. The installation stability of the permanent magnet is improved, and the installation requirement of the permanent magnet in a large surface-mounted permanent magnet motor is met.

Description

Technical Field

[0001] The present invention relates to the field of permanent magnet motors, and in particular to a magnetic pole fixing and limiting structure for a surface-mounted permanent magnet motor. Background Art

[0002] A permanent magnet motor generally refers to a motor that uses permanent magnets to create a magnetic field. Several permanent magnets are evenly installed along the circumferential direction on the outside of the rotor of the permanent magnet motor, and a three-phase stator winding is set on the outside of the stator. When the winding is connected to current, a rotating magnetic field is formed. The rotating magnetic field interacts with the permanent magnets to generate torque and drive the rotor to rotate.

[0003] Permanent magnet motors can be divided into surface-mounted and built-in types based on the installation position of the permanent magnets. In built-in permanent magnet motors, the permanent magnets are embedded inside the rotor, while in surface-mounted permanent magnet motors, the permanent magnets are located on the surface of the rotor. Therefore, the rotor structure of surface-mounted permanent magnet motors is relatively simple, making it easy to achieve optimal design and improve the motor's operating performance. In the prior art, there are three common installation methods for surface-mounted permanent magnets. The first is to add a carbon fiber protective cover to the outside of the permanent magnet and connect the permanent magnet to the rotor through elasticity. The second is to add magnetic isolation strips between adjacent permanent magnets and clamp the permanent magnets to the rotor through the magnetic isolation strips. Finally, the permanent magnets can also be directly adhered to the outside of the rotor.

[0004] Regarding the above-mentioned related technologies, when installing the permanent magnets of a surface-mounted permanent magnet motor, if an additional carbon fiber protective cover is used to fix the permanent magnets, the mechanical air gap of the motor will be increased, and the manufacturing cost will be increased; when the permanent magnets are fixed by means of magnetic isolation strips, since the magnetic isolation strips need to be connected to the rotor by bolts, the width of the magnetic isolation strips needs to meet the installation requirements of the bolts. If the width of the magnetic isolation strips is wider, it will affect the distance between adjacent permanent magnets and limit the pole arc coefficient of the permanent magnets; and if the permanent magnets are directly adhered to the outside of the rotor, the fixing method is mainly suitable for small motors. For large motors, the rotor diameter is larger, and when the rotor rotates, the permanent magnets are subjected to a larger centrifugal force, so they are easy to fall off the rotor. Therefore, there is an urgent need for a new installation structure to meet the installation requirements of permanent magnets in large surface-mounted motors. Summary of the Invention

[0005] In order to meet the installation requirements of permanent magnets in large surface-mounted permanent magnet motors, the present application provides a magnetic pole fixing and limiting structure for surface-mounted permanent magnet motors.

[0006] The present application provides a magnetic pole fixing and limiting structure for a surface-mounted permanent magnet motor, which adopts the following technical solutions: A magnetic pole fixing and limiting structure for a surface-mounted permanent magnet motor comprises a stator and a rotor, wherein the rotor is located in a positioning member and has an air gap with the stator, and a plurality of permanent magnets are provided on the outer side of the rotor along the circumferential direction, and the permanent magnets are parallel to the rotor axis, and the rotor is provided with a plurality of mounting grooves corresponding to the permanent magnets along the circumferential direction, one side of the permanent magnet is inserted into the mounting groove and fits with the inner wall of the mounting groove, and the inner wall of the mounting groove is evenly covered with magnetic steel glue, and the rotor is bonded and fixed to the permanent magnet by the magnetic steel glue, and two groups of positioning disks are provided in the axial direction of the rotor, and all permanent magnets are located between the two positioning disks, and the positioning disk is provided with a fixing screw, and the fixing screw passes through the positioning disk and is threadedly connected to the rotor, and positioning parts are provided at both ends of the permanent magnet along the axial direction of the rotor, and the end face of the positioning part facing away from the rotor axis is set as a contact surface, and the contact surface gradually approaches the rotor axis in the direction away from the permanent magnet, and a positioning ring is fixed circumferentially on the side of the positioning disk close to the permanent magnet, and the end of the positioning part away from the permanent magnet is located in the positioning ring.

[0007] By adopting the above technical solution, the stator supports the rotor, and the permanent magnet is embedded in the installation groove. The rotor increases the contact area with the permanent magnet through the installation groove, thereby increasing the coverage area of ​​the magnetic steel glue to improve the adhesion stability of the rotor to the permanent magnet. The rotor supports the positioning plate through the fixing screw, so that the positioning plate rotates with the rotor. When the positioning plate rotates, it drives the positioning ring to move. By setting the contact surface, the positioning portion extends into the positioning ring, and the radius of the outer circle of the positioning ring does not need to be greater than the distance between the end face of the permanent magnet facing away from the rotor and the rotor axis, which is conducive to reducing the mechanical air gap between the permanent magnet and the stator. At the same time, the positioning plate limits the positioning portion through the positioning ring. When the permanent magnet has a tendency to drive the positioning portion away from the rotor, the positioning plate limits the positioning portion through the positioning ring, which is conducive to further improving the installation stability of the permanent magnet. When installing the permanent magnet, there is no need to set magnetic isolation strips and carbon fiber protective covers. It is suitable for the installation requirements of permanent magnets in large surface-mounted permanent magnet motors.

[0008] Optionally, a limiting ring is provided between the positioning disk and the rotor, and the positioning disk and the rotor cooperate to clamp the limiting ring. The limiting ring is circumferentially fixed with a plurality of toggle plates corresponding to the permanent magnets one by one. The positioning disk is provided with an avoidance opening adapted to the toggle plate. The toggle plate is tilted in the direction away from the limiting ring, from the permanent magnet to the positioning disk. The toggle plate is made of a deformable material, and an abutment block is fixed at one end of the toggle plate away from the positioning disk. The abutment block is located on the side of the toggle plate close to the permanent magnet, and contacts the side of the abutment surface away from the permanent magnet.

[0009] By adopting the above technical solution, the positioning plate and the rotor cooperate to clamp and position the limit ring. When the limit ring moves, it drives all the toggle plates and the resistance blocks to move. The positioning plate avoids the toggle plates and the resistance blocks through the avoidance opening. In the initial state, the resistance block is located close to the rotor axis. When the rotation speed of the rotor increases, the resistance block moves away from the rotor under the action of centrifugal force and has a tendency to approach the permanent magnet. At this time, the resistance block applies a thrust to the permanent magnet close to the rotor through the resistance surface, and the permanent magnet is pressed against the rotor, further reducing the probability of the permanent magnet detaching from the rotor.

[0010] Optionally, an elastic plate is provided at one end of the toggle plate close to the limit ring, and the positioning plate is provided with a slot adapted to the elastic plate. The end of the elastic plate away from the toggle plate is located in the slot and is clamped with the positioning plate. When the elastic plate is in a natural state, the abutment block contacts the end of the abutment surface away from the permanent magnet.

[0011] By adopting the above technical solution, the positioning plate limits the elastic plate through the card slot, so that the elastic plate positions the toggle plate. When the rotor rotates, the toggle plate is driven to move, and the elastic plate is deformed. When the rotor stops, the elastic plate drives the toggle plate to reset, thereby reducing the probability of deformation of the toggle plate under long-term working conditions and improving the service life of the toggle plate.

[0012] Optionally, the stator includes an iron core, a plurality of windings and a shell. The shell is sleeved on the outside of the iron core and supports and fixes the iron core. The rotor is rotatably connected to the shell. The iron core is provided with a placement cavity adapted for the rotor. The rotor is located in the placement cavity and does not contact the iron core. The plurality of windings are arranged circumferentially along the placement cavity. A central control unit for controlling the operation of the windings is fixedly provided on the outside of the shell. A triggering member is provided at the axial end of the iron core. The triggering member is connected to the central control unit. When the interference block moves away from the permanent magnet along the contact surface, the contact member is triggered. After the triggering member is triggered, a signal is sent to the central control unit. After receiving the signal, the central control unit controls the winding to stop working.

[0013] By adopting the above technical solution, the shell supports the iron core and the rotor, and the iron core supports and fixes the winding. In the initial state, when the trigger member is not triggered, the winding works normally. When the winding works, a rotating magnetic field is generated, and the rotating magnetic field cooperates with the permanent magnet to drive the rotor to rotate. When any permanent magnet separates from the rotor and moves away from the rotor, the movement of the permanent magnet drives the positioning part to move, so that the positioning column pushes the resistance block to move away from the permanent magnet through the resistance surface. When the resistance block passes through the avoidance groove and contacts the trigger member, the trigger member is triggered, and then the trigger member controls the winding to stop working through the central control unit, thereby reducing the speed of the rotor, which is beneficial to reducing the probability of the detached permanent magnet colliding with the inner wall of the iron core placement cavity.

[0014] Optionally, the contact member includes a mounting ring, which is detachably connected to the iron core, and an annular cavity is provided in the mounting ring, in which a vibration sensor connected to the central control is placed, and a movable groove corresponding to the interference block is provided on the side of the mounting ring close to the positioning cover, and the interference block enters the movable groove when it is away from the permanent magnet, and the mounting ring is provided with an abutment ring, which is located in the movable groove and is slidingly connected to the mounting ring along the axial direction, and an elastic member is provided between the abutment ring and the mounting ring, and the elastic member is used to push the abutment ring away from the vibration sensor, and trigger the vibration sensor when the abutment ring contacts the vibration sensor, and after the vibration sensor is triggered, the winding is controlled to stop working through the central control.

[0015] By adopting the above technical solution, the iron core supports the vibration sensor in the annular cavity through the mounting ring. In the initial state, the abutment ring is away from the vibration sensor under the action of the elastic member, and the vibration sensor is in an untriggered state. The abutment block enters the movable groove when it is away from the permanent magnet under the push of the positioning part. When the abutment block contacts the abutment ring, it pushes the abutment ring to move along the movable groove. After the abutment ring contacts the vibration sensor, the vibration sensor is triggered, and then the winding is controlled to stop working through the central member, so that the rotor slows down.

[0016] Optionally, the annular cavity is coated with an electromagnetic shielding layer, the elastic part is an elastic membrane, the elastic membrane is located on the side of the annular cavity close to the movable groove, and the elastic membrane is also coated with an electromagnetic shielding layer, the abutment ring is connected to the elastic membrane, and when the abutment ring moves in a direction away from the permanent magnet, the vibration sensor is triggered through the elastic module.

[0017] By adopting the above technical solution, the elastic membrane is used to seal the movable groove, so that the vibration sensor in the annular cavity is in a closed cavity, and the vibration sensor is isolated from the outside world through the electromagnetic shielding layer, reducing the probability of the vibration sensor being affected by the external electromagnetic field.

[0018] Optionally, the positioning portion is made of non-magnetic material and is fixedly connected to the permanent magnet by bonding.

[0019] By adopting the above technical solution, the non-magnetic positioning portion is less likely to affect the magnetic field distribution of the permanent magnet, which is beneficial to improving the working stability of the permanent magnet.

[0020] Optionally, the rotor is provided with a plurality of positioning grooves along the length direction of the mounting groove, the inner wall of the positioning groove includes a bottom wall facing the permanent magnet and side walls located on both sides of the bottom surface, and the end surface of the permanent magnet close to the positioning groove is set as the mounting surface. For any positioning groove, at least one side wall has an obtuse angle with the mounting surface.

[0021] By adopting the above technical solution, when the magnetic steel glue is coated into the installation groove, the magnetic steel glue enters the positioning groove. When the magnetic steel glue in the positioning groove solidifies, a solid glue block is formed. In addition, due to the obtuse angle structure between the side wall and the installation surface, the bottom wall and the side wall cooperate to limit the tendency of the solid glue block to move away from the rotor, thereby improving the adhesion effect of the magnetic steel glue and the rotor and improving the installation stability of the permanent magnet.

[0022] In summary, this application includes at least one of the following beneficial technical effects: 1. The stator supports the rotor, and the permanent magnet is embedded in the installation groove. The rotor increases the contact area with the permanent magnet through the installation groove, thereby increasing the coverage area of ​​the magnetic steel glue to improve the adhesion stability of the rotor to the permanent magnet. The rotor supports the positioning plate through the fixing screws, so that the positioning plate rotates with the rotor. When the positioning plate rotates, it drives the positioning ring to move, and by setting the contact surface, the positioning part extends into the positioning ring, and the radius of the outer circle of the positioning ring does not need to be greater than the distance between the end face of the permanent magnet facing away from the rotor and the rotor axis, which is conducive to reducing the mechanical air gap between the permanent magnet and the stator. At the same time, the positioning plate limits the positioning part through the positioning ring. When the permanent magnet has a tendency to drive the positioning part away from the rotor, the positioning plate limits the positioning part through the positioning ring, which is conducive to further improving the installation stability of the permanent magnet. There is no need to set magnetic isolation strips and carbon fiber protective covers when installing the permanent magnet. It is suitable for the installation requirements of permanent magnets in large surface-mounted permanent magnet motors; 2. The positioning plate cooperates with the rotor to clamp and position the limit ring. When the limit ring moves, it drives all the toggle plates and the resistance blocks to move. The positioning plate avoids the toggle plates and the resistance blocks through the avoidance opening. In the initial state, the resistance block is located close to the rotor axis. When the rotor speed increases, the resistance block moves away from the rotor under the action of centrifugal force and has a tendency to approach the permanent magnet. At this time, the resistance block applies a thrust to the permanent magnet close to the rotor through the resistance surface, and the permanent magnet is pressed against the rotor, further reducing the probability of the permanent magnet detaching from the rotor. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall structure of the embodiment.

[0024] Figure 2 This is a schematic diagram intended to highlight the stator and rotor structures.

[0025] Figure 3 yes Figure 2 Enlarged schematic diagram of part A.

[0026] Figure 4 This is a schematic diagram intended to highlight the positions of the positioning slots and installation slots.

[0027] Explanation of the accompanying drawings: 1. Stator; 11. Iron core; 12. Housing; 13. Winding; 14. Central control unit; 2. Rotor; 21. Permanent magnet; 211. Positioning part; 212. Contact surface; 22. Mounting groove; 23. Positioning groove; 3. Positioning plate; 31. Fixing screw; 32. Positioning ring; 321. Buffer pad; 33. Limiting ring; 331. Toggle plate; 332. Contact block; 34. Elastic plate; 35. Slot; 4. Trigger member; 41. Mounting ring; 411. Annular cavity; 412. Moving groove; 42. Vibration sensor; 43. Contact ring; 44. Elastic member. DETAILED DESCRIPTION

[0028] The present application is further described in detail below in conjunction with all the accompanying drawings.

[0029] The embodiments of the present application disclose a magnetic pole fixing and limiting structure for a surface-mounted permanent magnet motor.

[0030] Example: Reference Figure 1 and Figure 2 A magnetic pole fixing and limiting structure for a surface-mounted permanent magnet motor includes a stator 1 and a rotor 2. The stator 1 comprises, from the inside out, an iron core 11 and a housing 12. The housing 12 is hollow, and the iron core 11 is mounted within the housing 12, which secures and supports the iron core 11. The iron core 11 defines a cavity, and the rotor 2 is located within the cavity and is rotatably connected to the housing 12.

[0031] Reference Figure 2 and Figure 3 The core 11 is provided with a plurality of windings 13 along the circumference of the placement cavity, and the housing 12 is equipped with a central control 14 for controlling the operation of the windings 13. The rotor 2 is located between all the windings 13, and the rotor 2 is provided with a plurality of permanent magnets 21 along the circumference, and the permanent magnets 21 are arranged along the circumference of the rotor 2. The rotor 2 is provided with mounting grooves 22 corresponding one to one with the permanent magnets 21. The side of the permanent magnet 21 close to the rotor 2 is located in the mounting groove 22 and contacts the inner wall of the mounting groove 22. Magnetic steel glue is provided between the rotor 2 and the permanent magnet 21. The magnetic steel glue is evenly coated on the inner wall of the mounting groove 22. The magnetic steel glue is a commonly used adhesive material in this field, such as epoxy resin glue, anaerobic glue, etc.

[0032] Reference Figure 3 and Figure 4The mounting groove 22 is conducive to increasing the contact area between the rotor 2 and the permanent magnet 21, so that the end surface of the permanent magnet 21 close to the rotor 2 and both sides along the length direction are in contact with the rotor 2 through the magnetic steel glue, thereby increasing the contact area between the rotor 2 and the permanent magnet 21 and improving the connection stability between the rotor 2 and the magnetic steel glue. Furthermore, the rotor 2 is provided with a positioning groove 23 connected to the mounting groove 22 along the length direction. The end surface of the permanent magnet 21 facing the mounting groove 22 is set as the mounting surface, and the end surface of the inner wall of the positioning groove 23 facing the mounting surface is set as the bottom wall, and the inner wall of the positioning groove 23 is provided with side walls on both sides along the length direction, and all side walls intersect with the mounting surface corresponding to the permanent magnet 21. When the magnetic steel glue is applied, the magnetic steel glue enters the positioning groove 23 and fills the positioning groove 23.

[0033] Reference Figure 3 and Figure 4 After the magnetic steel glue in the positioning grooves 23 solidifies, it forms a fixed rubber block. For all positioning grooves 23, at least one sidewall forms an obtuse angle with the corresponding mounting surface. Once the magnetic steel glue solidifies into a solid rubber block, the rotor 2 uses the positioning grooves 23 to restrain the solid rubber block, thereby reducing the probability of separation between the solid rubber block and the rotor 2 and improving the connection stability between the permanent magnets 21 and the rotor 2. When the control 14 controls the operation of the winding 13, the winding 13 generates a rotating magnetic field. The rotating magnetic field cooperates with the permanent magnets 21 to generate torque and drive the rotor 2 to rotate.

[0034] Reference Figure 3 and Figure 4 The permanent magnet 21 is provided with a positioning portion 211 at both ends along the axial direction. The positioning portion 211 is made of non-magnetic material, such as copper, aluminum, ceramic or plastic. The positioning portion 211 is connected to the permanent magnet 21 by magnetic steel glue, so that when the permanent magnet 21 moves, the positioning portion 211 is driven to move, and the positioning portion 211 is not easy to interfere with the magnetic field of the permanent magnet 21, which is beneficial to reduce the impact on the performance of the permanent magnet 21. The side of the positioning portion 211 facing away from the rotor 2 is set as a contact surface 212, and the contact surface 212 gradually approaches the rotor 2 in the direction away from the permanent magnet 21. The rotor 2 is provided with a positioning disk 3 at both ends along the length direction. The positioning disk 3 is provided with a plurality of fixing screws 31. The fixing screws 31 pass through the positioning disk 3 and are threadedly connected to the rotor 2. Under the connection action of the fixing screws 31, when the rotor 2 rotates, the positioning disk 3 is driven to rotate.

[0035] Reference Figure 2 and Figure 3The radius of the positioning disk 3 is smaller than the distance between the end face of the permanent magnet 21 facing away from the rotor 2 and the axis of the rotor 2. A positioning ring 32 is fixedly mounted on the side of the positioning disk 3 closest to the permanent magnet 21. The end of the positioning portion 211 facing away from the permanent magnet 21 is located within the positioning ring 32. A cushioning pad 321 is fixedly mounted on the inner wall of the positioning ring 32 along the circumference. When the permanent magnet 21 separates from the rotor 2 during high-speed rotation, it drives the positioning portion 211 toward the positioning ring 32. At this time, the positioning ring 32 supports the positioning portion 211 via the cushioning pad 321, thereby preventing the permanent magnet 21 from separating from the rotor 2 and further improving the installation stability of the permanent magnet 21.

[0036] Reference Figure 2 and Figure 3 A retaining ring 33 is provided between the positioning disk 3 and the rotor 2. The two sides of the retaining ring 33 contact the positioning disk 3 and the rotor 2, respectively. The positioning disk 3 and the rotor 2 cooperate to clamp and position the retaining ring 33. The retaining ring 33 is circumferentially fixed with a plurality of toggle plates 331 corresponding one-to-one with the permanent magnets 21. The toggle plates 331 are made of an elastic material, such as spring steel. The toggle plates 331 gradually move away from the permanent magnets 21 along the axis of the retaining ring 33, pointing toward the outer circumference of the retaining ring 33. The positioning disk 3 is provided with avoidance grooves corresponding one-to-one with the toggle plates 331, and the toggle plates 331 are located in the corresponding avoidance grooves.

[0037] Reference Figure 2 and Figure 3 , a contact block 332 is fixed to the end of the toggle plate 331 away from the limit ring 33. The contact block 332 is located at the end of the positioning block away from the permanent magnet 21 and contacts the contact surface 212. When the rotor 2 rotates, the toggle plate 331 and the contact block 332 move away from the rotor 2 under the action of centrifugal force, and at the same time approach the permanent magnet 21. At this time, under the action of the contact surface 212, the contact block 332 applies an extrusion force toward the axis of the rotor 2 to the positioning portion 211, which helps to further reduce the probability of the permanent magnet 21 detaching from the rotor 2. When the rotor 2 stops, the toggle plate 331 drives the contact block 332 to reset under the action of its own elasticity.

[0038] Reference Figure 2 and Figure 3An elastic plate 34 is disposed between the toggle plate 331 and the positioning disk 3. One end of the elastic plate 34 is connected to the toggle plate 331, so that movement of the toggle plate 331 drives the elastic plate 34 with it. The positioning disk 3 defines a slot 35 adapted for the elastic plate 34. The end of the elastic plate 34, distal from the toggle plate 331, is inserted into the slot 35 and engages with the positioning disk 3. The positioning disk 3 and the toggle plate 331 cooperate to limit the position of the elastic plate 34. When the toggle plate 331 deforms under the action of centrifugal force, it drives the elastic plate 34 to deform synchronously. When the rotor 2 stops, the elastic plate 34 drives the toggle plate 331 to return to its original position. This helps reduce the probability of deformation of the toggle plate 331 during long-term operation and increases the service life of the toggle plate 331.

[0039] Reference Figure 2 and Figure 3 The iron core 11 is provided with a trigger member 4 at its axial end. The trigger member 4 includes a mounting ring 41, multiple vibration sensors 42, and a contact ring. The mounting ring 41 is coaxially arranged with the rotor 2. The rotor 2 is provided with a motor output shaft, which passes through the mounting ring 41. The mounting ring 41 is provided with multiple mounting screws, which pass through the mounting ring 41 and are threadedly connected to the iron core 11, thereby supporting and fixing the mounting ring 41.

[0040] Reference Figure 2 and Figure 3 The mounting ring 41 defines a circumferentially sealed annular cavity 411. Multiple vibration sensors 42 are located within the annular cavity 411 and are arranged circumferentially along the annular cavity 411. The mounting ring 41 is located on the side of the positioning plate 3 facing away from the retaining ring 33. A movable groove 412 communicating with the annular cavity 411 is defined on the end surface of the mounting ring 411 proximal to the positioning plate 3. The interference ring is located within the movable groove 412 and is slidably connected to the inner wall of the movable groove 412 along the axial direction. An elastic member 44 is provided between the mounting ring 41 and the interference ring. The elastic member 44 is an elastic membrane located within the annular cavity 411 and fixedly connected to the mounting ring 41.

[0041] Reference Figure 2 and Figure 3 The side of the abutment ring 43 facing away from the positioning plate 3 is fixedly connected to the elastic membrane. When the elastic membrane is in its natural state, the abutment ring 43 is close to the abutment block 332. The elastic membrane seals the movable groove 412, keeping the annular cavity in a sealed state. The inner wall of the annular cavity 411 and the elastic membrane are both coated with an electromagnetic shielding layer, thereby reducing the impact of the magnetic field of the permanent magnet 21 and the winding 13 on the vibration sensor 42.

[0042] Reference Figure 2 and Figure 3When the permanent magnet 21 is separated from the rotor 2, the positioning portion 211 pushes the contact block 332 away from the permanent magnet 21 via the contact surface 212, causing the contact block 332 to pass through the avoidance groove and enter the movable groove 412. When the contact block 332 contacts the contact ring 43, it pushes the contact ring 43 toward the vibration sensor 42. All vibration sensors 42 are connected to the central control unit 14. When the contact ring drives the elastic membrane to contact any vibration sensor 42, the vibration sensor 42 is triggered. After the vibration sensor 42 is triggered, it sends a signal to the central control unit 14. After receiving the signal from the vibration sensor 42, the hollow part controls the winding 13 to stop working, thereby reducing the probability of damage caused by the permanent magnet 21 colliding with the iron core 11 due to the continued rotation of the rotor 2.

[0043] The implementation principle of the magnetic pole fixing and limiting structure for a surface-mounted permanent magnet motor in the embodiment of the present application is as follows: the permanent magnet 21 is embedded in the mounting groove 22, thereby increasing the contact area between the rotor 2 and the permanent magnet 21, which is conducive to improving the adhesion effect of the magnetic steel glue on the permanent magnet 21. At the same time, under the connection action of the fixing screw 31, the positioning ring 32 is driven to move through the positioning cover when the rotor 2 rotates, and the positioning ring 32 limits the positioning portion 211. When the rotor 2 rotates, the toggle plate 331 and the contact block 332 approach the permanent magnet 21 under the action of centrifugal force. At this time, the contact block 332 applies a thrust pointing to the axis of the rotor 2 to the positioning portion 211 through the contact surface 212, so as to improve the connection stability between the permanent magnet 21 and the rotor 2. When the permanent magnet 21 is disengaged from the mounting groove 22, the positioning portion 211 pushes the contact block 332 toward the trigger member 4 through the contact surface 212. After the contact block 332 contacts the contact ring, it drives the release ring to approach the vibration sensor 42. After the vibration sensor 42 is triggered, it transmits a signal to the central control unit 14, so that the central control unit 14 controls the winding 13 to stop working. At this time, the rotating magnetic field on the permanent magnet 21 disappears, which makes it easier to decelerate the rotor 2, thereby reducing the damage to the permanent magnet 21 and the iron core 11, and protecting the stator 1. It is suitable for the installation requirements of permanent magnets 21 in large surface-mounted permanent magnet motors.

[0044] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A magnetic pole fixing and limiting structure for a surface mounted permanent magnet motor, comprising a stator (1) and a rotor (2), wherein the rotor (2) is located in a positioning position and an air gap exists between the rotor (2) and the stator (1), and a plurality of permanent magnets (21) are arranged on the outer side of the rotor (2) along the circumferential direction, and the permanent magnets (21) are parallel to the axis of the rotor (2), characterized in that: The rotor (2) is provided with a plurality of mounting grooves (22) corresponding to the permanent magnets (21) along the circumferential direction. One side of the permanent magnet (21) is inserted into the mounting groove (22) and fits with the inner wall of the mounting groove (22). The inner wall of the mounting groove (22) is evenly covered with magnetic steel glue. The rotor (2) is bonded and fixed to the permanent magnet (21) by the magnetic steel glue. The rotor (2) is provided with two sets of positioning plates (3) along the axial direction. All the permanent magnets (21) are located between the two positioning plates (3). The positioning plates (3) are provided with fixing screws (31). The fixing screws (31) are provided with the fixing screws (31). 1) passes through a positioning disk (3) and is threadedly connected to a rotor (2); both ends of the permanent magnet (21) along the axial direction of the rotor (2) are provided with positioning portions (211); the end surface of the positioning portion (211) away from the axis of the rotor (2) is set as a contact surface (212); the contact surface (212) gradually approaches the axis of the rotor (2) in a direction away from the permanent magnet (21); a positioning ring (32) is fixedly provided along the circumferential direction on one side of the positioning disk (3) close to the permanent magnet (21); and the end of the positioning portion (211) away from the permanent magnet (21) is located inside the positioning ring (32).

2. The magnetic pole fixing and limiting structure for a surface mounted permanent magnet motor according to claim 1, characterized in that: A limiting ring (33) is provided between the positioning disk (3) and the rotor (2). The positioning disk (3) and the rotor (2) cooperate to clamp the limiting ring (33). The limiting ring (33) is fixedly provided with a plurality of toggle plates (331) corresponding to the permanent magnets (21) along the circumferential direction. The positioning disk (3) is provided with an escape opening adapted to the toggle plates (331). The toggle plates (331) are inclined in a direction away from the limiting ring (33) from the permanent magnet (21) to the positioning disk (3). The toggle plates (331) are made of a deformable material. An abutment block is fixedly provided at one end of the toggle plates (331) away from the positioning disk (3). The abutment block is located on a side of the toggle plates (331) close to the permanent magnet (21) and in contact with a side of the abutment surface (212) away from the permanent magnet (21).

3. The magnetic pole fixing and limiting structure for a surface mounted permanent magnet motor according to claim 2, characterized in that: An elastic plate (34) is provided at one end of the toggle plate (331) close to the limiting ring (33); the positioning plate (3) is provided with a clamping groove (35) adapted to the elastic plate (34); an end of the elastic plate (34) away from the toggle plate (331) is located in the clamping groove (35) and is clamped with the positioning plate (3); and in a natural state of the elastic plate (34), the abutment block contacts the end of the abutment surface (212) away from the permanent magnet (21).

4. The magnetic pole fixing and limiting structure for a surface mounted permanent magnet motor according to claim 2, characterized in that: The stator (1) comprises an iron core (11), a plurality of windings (13) and an outer shell (12); the outer shell (12) is sleeved on the outer side of the iron core (11) and supports and fixes the iron core (11); the rotor (2) is rotatably connected to the outer shell (12); the iron core (11) is provided with a placement cavity adapted to the rotor (2); the rotor (2) is located in the placement cavity and does not contact the iron core (11); the plurality of windings (13) are arranged along the circumference of the placement cavity; a central control unit (14) for controlling the operation of the windings (13) is fixedly arranged on the outer side of the outer shell (12); a triggering member (4) is arranged at an axial end of the iron core (11); the triggering member (4) is connected to the central control unit (14); when the abutment block (332) moves away from the permanent magnet (21) along the contact surface, the contacting member is triggered; after being triggered, the triggering member (4) sends a signal to the central control unit (14); after receiving the signal, the central control unit (14) controls the winding (13) to stop working.

5. The magnetic pole fixing and limiting structure for a surface mounted permanent magnet motor according to claim 4, characterized in that: The contact member comprises a mounting ring (41), the mounting ring (41) is detachably connected to the iron core (11), an annular cavity (411) is provided in the mounting ring (41), a vibration sensor (42) connected to the central control unit (14) is placed in the annular cavity (411), a moving groove (412) corresponding to the abutment block (332) is provided on a side of the mounting ring (41) close to the positioning cover, and when the abutment block (332) is away from the permanent magnet (21), it enters the moving groove (412), and the mounting ring (41) is provided with an abutment The abutment ring (43) is located in the movable groove (412) and is slidably connected with the mounting ring (41) along the axial direction. An elastic member (44) is provided between the abutment ring (43) and the mounting ring (41). The elastic member (44) is used to push the abutment ring (43) away from the vibration sensor (42). When the abutment ring (43) contacts the vibration sensor (42), the vibration sensor (42) is triggered. After the vibration sensor (42) is triggered, the winding (13) is controlled to stop working through the central control unit (14).

6. The magnetic pole fixing and limiting structure for a surface mounted permanent magnet motor according to claim 5, characterized in that: The annular cavity (411) is coated with an electromagnetic shielding layer, the elastic member (44) is an elastic membrane, the elastic membrane is located on a side of the annular cavity (411) close to the movable groove (412), and the elastic membrane is also coated with an electromagnetic shielding layer, the abutment ring (43) is connected to the elastic membrane, and when the abutment ring (43) moves in a direction away from the permanent magnet (21), the vibration sensor (42) is triggered through the elastic module.

7. The magnetic pole fixing and limiting structure for a surface mounted permanent magnet motor according to claim 1, characterized in that: The positioning portion (211) is made of non-magnetic material and is fixedly connected to the permanent magnet (21) by bonding.

8. The magnetic pole fixing and limiting structure for a surface mounted permanent magnet motor according to claim 1, characterized in that: The rotor (2) is provided with a plurality of positioning grooves (23) along the length direction of the mounting groove (22); the inner wall of the positioning groove (23) comprises a bottom wall directly facing the permanent magnet (21) and side walls located on both sides of the bottom surface; the end surface of the permanent magnet (21) close to the positioning groove (23) is set as a mounting surface; for any positioning groove (23), at least one of the side walls has an obtuse angle with the mounting surface.

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