Motor

Abstract

The present invention relates to an electric motor, comprising a rotor assembly and a stator assembly, wherein the rotor assembly has a rotating shaft and a permanent magnet arranged around the rotating shaft; the stator assembly comprises: a first pole claw carrier, on which a plurality of first pole claws uniformly distributed along the circumferential direction and first pole claw slots located between adjacent first pole claws are alternately arranged; a second pole claw carrier, on which a plurality of second pole claws uniformly distributed along the circumferential direction and second pole claw slots located between adjacent second pole claws are alternately arranged; and a housing, comprising a wall surrounding the plurality of first pole claws and the plurality of second pole claws in an assembled state of the stator assembly, and a notch is arranged on the wall, wherein the first pole claw is inserted into the corresponding second pole claw slot, and the second pole claw is inserted into the corresponding first pole claw slot, so that when being excited, at least one pole claw of the plurality of first pole claws and the plurality of second pole claws is configured such that the actual working center line along the axial direction is offset from the corresponding pole claw slot center line by an angle ΔC in the same circumferential direction.

Description

Technical Field

[0001] The present invention relates to a motor, and more particularly to a pole claw type motor for minimizing a deviation between a clockwise rotation torque and a counterclockwise rotation torque. Background Art

[0002] In existing motors, especially claw-pole motors, due to the provision of casing slots for positioning and assembling connecting terminals, wire outlet slots for motor windings, assembly positioning holes and / or assembly avoidance slots and other gaps in the outer shell surrounding the stator claw poles, the complete magnetic circuit between the relative claw-pole carriers is destroyed, resulting in a deviation between the torques generated by the clockwise and counterclockwise rotation of the motor, affecting the clockwise and counterclockwise torque performance of the motor. Summary of the invention

[0003] The present invention is intended to overcome the above-mentioned problems in the prior art and has other advantages.

[0004] To this end, the present invention provides a motor, comprising:

[0005] a rotor assembly having a rotating shaft and permanent magnets disposed about the rotating shaft; and

[0006] A stator assembly comprising:

[0007] A first pole claw carrier, on which a plurality of first pole claws uniformly distributed along the circumferential direction and first pole claw grooves located between adjacent first pole claws are alternately arranged;

[0008] A second pole claw bearing member, on which a plurality of second pole claws uniformly distributed along the circumferential direction and second pole claw grooves located between adjacent second pole claws are alternately arranged;

[0009] A housing, wherein the housing has a wall surrounding the plurality of first pole claws and the plurality of second pole claws in the assembled state of the stator assembly, and the wall is provided with a notch, wherein the first pole claw is inserted into the corresponding second pole claw slot, and the second pole claw is inserted into the corresponding first pole claw slot, so that when excited, the actual working center line of at least one of the plurality of first pole claws and the plurality of second pole claws in the axial direction is offset by an angle ΔC in the same circumferential direction with the center line of the corresponding pole claw slot.

[0010] In such a motor, due to the presence of a gap in the housing of the stator assembly, such as a housing slot provided on the wall of the housing, there is a deviation in the torque generated by the clockwise and counterclockwise rotation of the motor, thereby affecting the torque performance of the motor when rotating clockwise and counterclockwise.

[0011] According to the definition of magnetic resistance, that is, the magnetic lines of force always have a tendency to close along the shortest path or the magnetic lines of force try to close along the path with the smallest magnetic resistance. Under this tendency, a torque is formed to align the center of the rotor pole with the center of the stator pole. Therefore, in the magnetic circuit of a motor with a claw structure, during the rotation of the rotor, when the center line of the rotor pole is aligned with the center line of the stator pole, the magnetic resistance is the smallest, the phase inductance is the largest, and the phase current rise rate is the smallest; when the center line of the rotor pole is aligned with the center line of the stator claw slot, the magnetic resistance is the largest, the phase inductance is the smallest, and the phase current rise rate is the largest.

[0012] Based on the definition of magnetic resistance and the above-mentioned characteristics of magnetic resistance, when a notch is provided on the housing of the stator assembly of the motor so that there is a deviation in the torque generated by the clockwise rotation and counterclockwise rotation of the motor, by making at least one of the multiple first pole claws and the multiple second pole claws in the assembled state have its actual working center in the axial direction offset from the corresponding pole claw slot center line in the same circumferential direction by an angle ΔC when being energized, it is possible to achieve an offset in the position where the rotor pole and the stator pole are aligned, thereby increasing the phase current in the direction when the rotor rotates in a direction where the output torque is relatively small, and thus increasing the torque of the motor in this direction; correspondingly, when the rotor rotates in a direction where the output torque is relatively large, the phase current in this direction is reduced, and thus reducing the torque of the motor in this direction, so that the torque deviation generated by the clockwise rotation and counterclockwise rotation of the motor can be effectively compensated.

[0013] According to a first embodiment of the present invention, each first pole claw has a first pole claw root connected to the first pole claw carrier, and the first pole claw has a first theoretical center line in the axial direction passing through the center of its first pole claw root; each second pole claw has a second pole claw root connected to the second pole claw carrier, and the second pole claw has a second theoretical center line in the axial direction passing through the center of its second pole claw root; wherein at least one pole claw among the plurality of first pole claws and the plurality of second pole claws is constructed to be asymmetrical relative to its theoretical center line, so that when excited, the actual working center line of the at least one pole claw is offset from its theoretical center line in the axial direction by the angle ΔC.

[0014] According to a first variant implementation of the first embodiment of the present invention, a material removal portion is provided on one side of the theoretical center line of the at least one pole claw to achieve an offset of the actual working center line of the at least one pole claw from its theoretical center line by the angle ΔC.

[0015] By providing the material removal portion, the actual working center line of the pole claw can be offset from its theoretical center line by the angle ΔC in a very simple manner without changing the structure and assembly of other components of the motor, thereby saving material and reducing costs.

[0016] In a specific implementation of the first variant, the material removal portion is a cut angle provided at the top of the corresponding pole claw. More specifically, the cut angle is an oblique angle or an arc angle, and the cut angle width w is not greater than half of the width l of the top of the pole claw. For example, the oblique angle includes but is not limited to a 45 degree oblique angle and a 60 degree oblique angle.

[0017] By implementing the material removal by such a chamfer, a simpler design and production can be further ensured.

[0018] According to a second implementation variation of the first embodiment of the present invention, a material increase portion is provided on one side of the theoretical center line of the at least one pole claw to achieve that the actual working center line of the at least one pole claw is offset from its theoretical center line by the angle ΔC.

[0019] Likewise, by providing a material increase, it can be achieved in a simple manner that the actual operating center line of the pole claw is offset from its theoretical center line by the angle ΔC.

[0020] According to a specific implementation of the first embodiment of the present invention, at least one first pole claw among the plurality of first pole claws is constructed to be asymmetric relative to the corresponding first theoretical center line, and at least one second pole claw among the plurality of second pole claws is constructed to be asymmetric relative to the corresponding second theoretical center line, and for the at least one first pole claw and the at least one second pole claw, the actual working center line is offset from the corresponding theoretical center line by the angle ΔC along the same circumferential direction.

[0021] According to a preferred implementation manner of the first embodiment of the present invention, at least two pole claws among the plurality of first pole claws and the plurality of second pole claws are constructed to be asymmetrical with respect to their theoretical center lines.

[0022] At least two pole claws realize an actual working center line offset from a corresponding theoretical center line by the angle ΔC along the same circumferential direction, which allows compensating for torque deviations caused by clockwise and counterclockwise rotations of the motor in a more effective manner.

[0023] According to the first embodiment of the present invention, the theoretical center line of the pole claw coincides with the pole claw slot center line of the corresponding pole claw slot, which is similar to the assembly method of the pole claw and the pole claw slot of the traditional motor.

[0024] According to a second embodiment of the present invention, the pole claws are assembled with the corresponding pole claw slots in a circumferentially angularly offset manner, so that the theoretical center line of the pole claws is offset from the pole claw slot center of the corresponding pole claw slot by the angle ΔC.

[0025] In the second embodiment, the pole claw itself does not need to be constructed to be asymmetrical along its theoretical center line, and it is only necessary to offset the pole claw and the corresponding pole claw slot in the circumferential direction at an angle when assembling the stator assembly. This allows the compensation of the torque deviation generated by the clockwise and counterclockwise rotation of the motor to be achieved without changing the structure of the pole claw of the traditional motor, thereby allowing standardized production and improving efficiency.

[0026] According to the first and second embodiments of the present invention, the absolute value of the angle ΔC is in the range of 1° to 3°, preferably 2°.

[0027] According to the first and second embodiments of the present invention, the first pole claw carrier is in the form of a pole claw plate, and the second pole claw carrier is integrated with the housing. For example, the pole claw plate has a plurality of first pole claws that are bent along the motor rotor rotation axis to one side and are evenly distributed in the circumferential direction with the rotor rotation axis as the center; the housing is columnar, and the second pole claw carrier has a plurality of second pole claws that are bent along the motor rotor rotation axis toward the inside of the housing and are evenly distributed in the circumferential direction with the rotor rotation axis as the center. This allows the number of components of the motor to be reduced, making assembly easier. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings of the embodiments of the present invention. The drawings are only used to illustrate some embodiments of the present invention, but not to limit all embodiments of the present invention thereto. In the drawings:

[0029] Figure 1 shows a perspective view of the motor according to the present invention in an assembled state;

[0030] Figure 2 A partially exploded perspective view of a motor according to the present invention is shown, which shows a rotor assembly, a stator assembly and a housing surrounding pole claws of the stator assembly of the motor;

[0031] Figure 3 A top view of a subassembly consisting of a second pole claw carrier and a housing according to the present invention is shown;

[0032] Figure 4 A side view of a subassembly consisting of a second pole claw carrier and a housing according to the present invention is shown;

[0033] Figure 5 A partial plan view of a first pole claw carrier with a first pole claw according to the present invention is shown;

[0034] Figure 6 A partial plan view of a second pole claw carrier with a second pole claw according to the present invention is shown;

[0035] Figure 7 A partial plan view of the first pole claw carrier and the second pole claw carrier according to the present invention in an assembled state is shown;

[0036] Figure 8 The diagram schematically shows the corresponding relationship between the magnetic poles of the first pole claw of the first pole claw carrier according to the present invention and the magnetic poles of the rotor;

[0037] Fig. 9 The corresponding relationship between the magnetic poles of the second pole claw of the second pole claw carrier according to the present invention and the magnetic poles of the rotor is schematically shown;

[0038] Fig.10 The comparison between the variation of the phase current and the phase inductance of the motor according to the present invention with the rotor rotation angle and the variation of the phase current and the phase inductance of the conventional motor with the rotor rotation angle is schematically shown. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the technical solution of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described in conjunction with the drawings of specific embodiments of the present invention. The same figure marks in the drawings represent the same parts. It should be noted that the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] Unless otherwise defined, the technical terms or scientific terms used herein shall have the usual meanings understood by persons of ordinary skill in the field to which the present invention belongs. The words "first", "second" and similar words used in the patent application specification and claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "one" do not necessarily indicate a quantity limitation. Words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0041] Figure 1 shows a three-dimensional schematic diagram of a motor according to the present invention, Figure 2 FIG. 2 shows a partially exploded perspective view of a motor according to the present invention. Figure 2As shown, the motor 1 according to the present invention comprises a rotor assembly 2 and a stator assembly 3, wherein the rotor assembly 2 comprises a rotating shaft 4 and a permanent magnet (not shown) arranged around the rotating shaft 4, and the stator assembly 3 comprises a first pole claw carrier 5, a second carrier 6 and a housing 7. A plurality of first pole claws 8 uniformly distributed along the circumferential direction and first pole claw slots 10 located between adjacent first pole claws 8 are alternately arranged on the first pole claw carrier 5, and a plurality of second pole claws 9 uniformly distributed along the circumferential direction and second pole claw slots 11 located between adjacent second pole claws 9 are alternately arranged on the second pole claw carrier 6. In the assembled state of the stator assembly 3, the first pole claws 8 are inserted into the corresponding second pole claw slots 11, and the second pole claws 9 are inserted into the corresponding first pole claw slots 10. The housing 7 has a wall surrounding the plurality of first pole claws 8 and the plurality of second pole claws 9 in the assembled state of the stator assembly 3, and a notch 12, such as a housing slot, is arranged on the wall.

[0042] According to the test, when there are no slots or notches on the outer shell of the stator assembly of the motor, there is no deviation between the torque generated by the clockwise rotation and the counterclockwise rotation of the motor. However, when there are slots or notches on the outer shell of the stator assembly of the motor, there is a deviation between the torque generated by the clockwise rotation and the counterclockwise rotation of the motor. In order to eliminate this phenomenon, according to the present invention, it is specifically proposed that when the pole claws are excited, the actual working center line c3 of at least one of the plurality of first pole claws 8 and the plurality of second pole claws 9 in the axial direction is offset by an angle ΔC from the corresponding pole claw slot center line c1 in the same circumferential direction.

[0043] In order to understand the present invention more clearly, the theoretical center line c1 of the pole claw, the actual working center line c3 and the pole claw slot center line c2 are defined as follows:

[0044] Theoretical center line c1 of the pole claw: the pole claw has a pole claw root connected to the corresponding pole claw carrier, and the line along the axial direction passing through the center of the pole claw root of the pole claw is the theoretical center line c1;

[0045] Actual working center line c3 of the pole claw: when the motor is working, when the winding is energized to excite the pole claw of the pole claw carrier, the line that passes through the pole claw in the axial direction and divides the excitation effect of the pole claw in half is the actual working center line c3 of the pole claw, that is, the pole claw is equally excited on both sides of its actual working center line c3;

[0046] Pole claw slot center line c2: A line along the axial direction and passing through the center of the pole claw slot is the pole claw slot center line c2.

[0047] In addition, in order to more clearly describe the present invention, the clockwise and counterclockwise rotation directions of the motor are defined as follows: Figure 1-2 and Figure 5-7As shown, when the rotor poles and the corresponding pole claw bearings are partially unfolded:

[0048] Clockwise: Observe from the rotor shaft end of the motor, that is, along the Y2 direction. The clockwise rotation direction of the rotor is displayed as along the X1 direction on the local plane development diagram.

[0049] Counterclockwise: Observe the rotor shaft end of the motor, that is, along the Y2 direction. The counterclockwise rotation direction of the rotor is displayed as along the X2 direction on the local plane development diagram.

[0050] In a specific embodiment, Figure 2 As shown, the first pole claw carrier 5 is in the form of a pole claw plate, and the second pole claw carrier 6 is integrated with the housing 7. For example, the first pole claw carrier 5 in the form of a pole claw plate has a plurality of first pole claws 8 that are bent to one side along the motor rotor rotation axis 4 and are evenly distributed in the circumferential direction with the rotor rotation axis 4 as the center; the housing 7 is columnar, and the second pole claw carrier 6 has a plurality of second pole claws 9 that are bent to the inside of the housing 7 along the motor rotor rotation axis 4 and are evenly distributed in the circumferential direction with the rotor rotation axis 4 as the center. In the motor, there is usually a notch 12 in the housing 7 of the stator assembly 3, such as a housing slot provided on the wall of the housing 7. In a specific embodiment, as Figure 3 and Figure 4 As shown, the structure of the motor housing 7 is constant, a housing slot with a depth of B and a width of A is set in the axial direction from one axial end of the housing 7, and the angle between the end points of the housing slot in the width direction and the theoretical center line c1 of a single pole claw is constant at α. Due to the existence of such a housing slot, the torque generated by the clockwise and counterclockwise rotation of the motor has a deviation, thereby affecting the torque performance of the motor when rotating clockwise and counterclockwise.

[0051] According to the definition of magnetic resistance, the magnetic lines of force always tend to close along the shortest path or try to close along the path with the least magnetic resistance. Under this trend, a torque is formed to align the center of the rotor pole with the center of the stator pole. Therefore, in the magnetic circuit of a motor with a claw structure, the magnetic lines of force tend to pass through the path with the least magnetic resistance. During the rotation of the rotor, when the center line of the rotor pole is aligned with the center line of the stator pole, the magnetic resistance is the smallest, the phase inductance is the largest, and the phase current rise rate is the smallest; when the center line of the rotor pole is aligned with the center line of the stator claw slot, the magnetic resistance is the largest, the phase inductance is the smallest, and the phase current rise rate is the largest.

[0052] Based on the definition of magnetic resistance and the above characteristics of magnetic resistance, when the rotor rotates in the direction with smaller output torque, if the phase current in that direction is increased, the torque of the motor in that direction can be effectively compensated. Taking the example of a motor rotor with larger torque when rotating clockwise, increasing the phase current in the counterclockwise direction of the motor rotor with smaller torque can compensate for the torque deviation caused by the clockwise and counterclockwise rotation of the motor rotor.

[0053] Therefore, when a notch 12 is provided on the housing 7 of the stator assembly 3 of the motor 1, by offsetting the actual working center line c3 in the axial direction of at least one of the multiple first pole claws 8 and the multiple second pole claws 9 by an angle ΔC in the same circumferential direction with the corresponding pole claw slot center line c1 when excited, it is possible to achieve an offset in the position where the rotor poles and the stator poles are aligned, thereby increasing the phase current in the direction when the rotor rotates in a direction where the output torque is relatively small, and thus increasing the torque of the motor in this direction; correspondingly, when the rotor rotates in a direction where the output torque is relatively large, the phase current in this direction is reduced, and thus reducing the torque of the motor in this direction, so that the torque deviation caused by the clockwise and counterclockwise rotation of the motor can be effectively compensated.

[0054] Specifically, it is assumed that the torque of the motor when rotating clockwise is greater than the torque when rotating counterclockwise due to the presence of the notch 12 on the housing 7 of the stator assembly 3. In this case, according to the present invention, it is possible to set the actual working center line c3 of at least one of the plurality of first pole claws 8 and the plurality of second pole claws 9 to be offset from the corresponding pole claw slot center line c1 in the clockwise direction by an angle ΔC when excited, that is, offset by an angle ΔC in the direction of X2, as shown in FIG. Fig.10 As shown. Therefore, before the pole claw is excited, the center of the rotor magnetic pole S pole (N pole) is aligned with the corresponding pole claw slot center line c1; when the pole claw is excited, the rotor magnetic pole S pole (N pole) tends to be aligned with the actual working center line c3 of the corresponding pole claw. At this time, since the actual working center line c1 of at least one pole claw is offset by an angle ΔC in the same circumferential direction with the corresponding pole claw slot center line c3, the stator coil excitation time is reduced when the rotor rotates clockwise, and the energy obtained by the stator coil is also reduced, thereby reducing the torque of the rotor rotating clockwise; correspondingly, the stator coil excitation time is increased when the rotor rotates counterclockwise, and the energy obtained by the stator coil is also increased, thereby increasing the torque of the rotor rotating counterclockwise.

[0055] At the same time, due to the change in the position of the actual working center line of the pole claw, the position of the maximum phase current Lmax and the minimum phase inductance Lmin changes, thereby reducing the clockwise torque of the motor rotor and increasing the counterclockwise torque of the motor rotor. Fig.10 The figure shows the variation of phase current and phase inductance with rotor rotation angle β when the motor rotates counterclockwise, which increases the torque of the motor rotor in the counterclockwise direction.

[0056] Therefore, in this case, the motor 1 according to the present invention makes it possible to reduce the clockwise rotation torque of the rotor and increase the counterclockwise rotation torque of the rotor, so as to reduce the deviation between the clockwise and counterclockwise rotation torques of the rotor and make them tend to be equal, thereby improving the performance of the motor.

[0057] Various embodiments of the present invention are given below, in which it is assumed that the torque of the motor when rotating clockwise is greater than the torque when rotating counterclockwise due to the presence of the notch 12 on the housing 7 of the stator assembly 3 .

[0058] like Figures 5 to 7 As shown, it shows a first embodiment according to the present invention, wherein at least one pole claw among the plurality of first pole claws 8 and the plurality of second pole claws 9 is constructed to be asymmetrical relative to its theoretical center line c1, so that when excited, the actual working center line c3 of the at least one pole claw is offset by an angle ΔC from its theoretical center line c1 in the axial direction. Figure 5 The first pole claw 8 is shown to be arranged asymmetrically with respect to its theoretical center line c1. Figure 6 The second pole claw 9 is shown to be arranged asymmetrically with respect to its theoretical center line c1. Figure 7 Shows when Figure 5 The first pole claw 8 and Figure 6 The second pole claw 9 is shown as a partial plan view when it is inserted into the corresponding second pole claw slot 11 and the first pole claw slot 10. In the first embodiment of the present invention, in the assembled state of the stator assembly 3, the theoretical center line c1 of the pole claw coincides with the pole claw slot center line c2 of the corresponding pole claw slot, as shown in FIG. Figure 7 shown.

[0059] According to a first implementation variation of the first embodiment of the present invention, Figures 5 to 7 As shown, material removal portions 13 and 14 are provided on one side of the theoretical center line c1 of the at least one pole claw to achieve an angle ΔC offset between the actual working center line c1 of the at least one pole claw and its theoretical center line c1. In a specific implementation of this first embodiment, the material removal portions 13 and 14 are cut angles provided at the top of the corresponding pole claw. More specifically, the cut angle is an oblique angle or an arc angle, and the cut angle width w is not greater than half of the width l of the top of the pole claw. For example, the oblique angle includes but is not limited to a 45-degree oblique angle and a 60-degree oblique angle. The provision of the material removal portion can achieve an angle ΔC offset between the actual working center line of the pole claw and its theoretical center line in a very simple manner without changing the structure and assembly of other components of the motor, thereby saving materials and reducing costs.

[0060] According to a specific implementation of the first embodiment of the present invention, at least one first pole claw 8 of the plurality of first pole claws 8 is constructed to be asymmetric with respect to the corresponding first theoretical center line c1, and at least one second pole claw 9 of the plurality of second pole claws 9 is constructed to be asymmetric with respect to the corresponding second theoretical center line c1, and for the at least one first pole claw 8 and the at least one second pole claw 9, an actual working center line c3 is offset from the corresponding theoretical center line c1 by an angle ΔC along the same circumferential direction (i.e., the direction of X2 shown in the figure), as shown in FIG. Figure 5-7 shown.

[0061] According to a preferred implementation of the first embodiment of the invention, at least two of the plurality of first pole claws 8 and the plurality of second pole claws 9 are constructed to be asymmetrical relative to their theoretical center line c1. This allows to ensure compensation of torque deviations generated by clockwise and counterclockwise rotations of the motor in a more effective manner.

[0062] like Figure 5 and Figure 8 As shown, on at least one pole claw 8, a material removal portion 13 is provided on the side deviated from the X1 direction with reference to the theoretical center line c1 of the pole claw, so that the at least one first pole claw 8 is asymmetric with respect to its theoretical center line c1, and thus the actual working center line c3 of the at least one first pole claw 8 is offset by an angle ΔC relative to its theoretical center line c1 along the X2 direction. In this case, before the at least one pole claw 8 is excited, the center c4 of the rotor magnetic pole S pole (N pole) is aligned with the corresponding pole claw slot center line c1; when the at least one first pole claw 8 is excited, the rotor magnetic pole S pole (N pole) tends to be aligned with the actual working center line c3 of the at least one first pole claw 8, which reduces the stator coil excitation time when the rotor rotates clockwise, and the stator coil obtains less energy, thereby reducing the torque of the rotor rotating clockwise; accordingly, the stator coil excitation time when the rotor rotates counterclockwise increases, and the stator coil obtains more energy, thereby increasing the torque of the rotor rotating counterclockwise. At the same time, due to the change in the position of the actual working center line of the pole claw, the position of the maximum phase current Lmax and the minimum phase inductance Lmin changes, such as Fig.10 shown.

[0063] Likewise, if Figure 6 and Fig. 9As shown, on at least two pole claws 9, a material removal portion 14 is provided on the side deviated from the X1 direction with reference to the theoretical center line c1 of the pole claw, so that the at least one second pole claw 9 is asymmetric with respect to its theoretical center line c1, and thus the actual working center line c3 of the at least one second pole claw 9 is offset by an angle ΔC along the X2 direction relative to its theoretical center line c1. In this case, before the at least one second pole claw 9 is excited, the center c4 of the rotor magnetic pole S pole (N pole) is aligned with the corresponding pole claw slot center line c1; when the at least one second pole claw 9 is excited, the rotor magnetic pole S pole (N pole) tends to be aligned with the actual working center line c3 of the at least one second pole claw 9, thereby achieving an effect similar to the above.

[0064] It should be noted that the structure of the material removal part of the pole claw depends on the shape, specification and size of the motor and the deviation between the clockwise and counterclockwise rotation torque of the rotor. For example, when the clockwise rotation torque of the rotor is larger, the larger the size of the material removal part of the pole claw, the more the current value in the counterclockwise rotation direction of the rotor is increased, thereby compensating for the larger torque in the counterclockwise rotation direction of the rotor.

[0065] According to a second variant implementation of the first embodiment of the present invention (not shown), a material increase portion is provided on one side of the theoretical center line c1 of the at least one pole claw to achieve an offset angle ΔC between the actual working center line c3 of the at least one pole claw and its theoretical center line c1. For example, in the case where the clockwise rotation torque of the rotor is relatively large, a material removal portion is provided on the side of the pole claw that is offset in the X2 direction based on the theoretical center line c1 of the pole claw, so that the pole claw is asymmetric with respect to its theoretical center line c1, and thereby the actual working center line c3 of the pole claw is offset in the X2 direction with respect to its theoretical center line c1 by an angle ΔC.

[0066] Similarly, the structure of the material increase portion of the pole claw is determined according to the shape, specification and size of the motor and the deviation between the clockwise and counterclockwise rotation torque of the rotor. For example, when the clockwise rotation torque of the rotor is larger, the larger the size of the material increase portion of the pole claw, the more the current value in the counterclockwise rotation direction of the rotor is increased, thereby compensating for the greater torque in the counterclockwise rotation direction of the rotor.

[0067] According to a second embodiment of the present invention (not shown), the pole claw and the corresponding pole claw slot are assembled in a manner of circumferential angular offset, so that the theoretical center line c1 of the pole claw is offset from the pole claw slot center line c2 of the corresponding pole claw slot by an angle ΔC. That is, in this second embodiment, it is not necessary to construct the pole claw itself to be asymmetrical along its theoretical center line c1, and it is only necessary to offset the pole claw and the corresponding pole claw slot at an angle in the circumferential direction when assembling the stator assembly 3. In this case, the actual working center line c3 of the pole claw coincides with its theoretical center line c1. This allows compensation for the torque deviation caused by clockwise and counterclockwise rotation of the motor without changing the structure of the pole claw of the conventional motor, thereby allowing standardized production and improving efficiency.

[0068] It should be noted that the first embodiment and the second embodiment according to the present invention can also be implemented in combination, that is, all implementation variations of the inventive concept that can achieve that when the pole claws are excited, the actual working center line c3 in the axial direction of at least one of the plurality of first pole claws 8 and the plurality of second pole claws 9 is offset from the corresponding pole claw slot center line c1 in the same circumferential direction by an angle ΔC are included in the scope of the present invention.

[0069] In the first and second embodiments according to the present invention, the value of the angle ΔC is in the range of 1° to 3°, preferably 2°.

[0070] Specifically, according to the experimental verification of a specific embodiment, it is found that when there is no offset angle ΔC, when the clockwise rotation torque of the motor rotor is constant at 20.93mN·M, the counterclockwise rotation torque of the motor rotor is 16.42mN·M, and the deviation from the clockwise rotation torque is -4.51mN·M; when the offset angle ΔC is 1°, the counterclockwise rotation torque of the motor rotor is 18.75mN·M, and the deviation from the clockwise rotation torque is -2.18mN·M; when the offset angle ΔC is 2°, the counterclockwise rotation torque of the motor rotor is 19.89mN·M, and the deviation from the clockwise rotation torque is -1.04mN·M; when the offset angle ΔC is 3°, the counterclockwise rotation torque of the motor rotor is 22.53mN·M, and the deviation from the clockwise rotation torque is 1.6mN·M. It can be seen from the above that the offset angle ΔC of 2° is the minimum deviation between the clockwise and counterclockwise rotation torques of the motor rotor. When the offset angle ΔC is 1°-3°, the torque deviation of the rotor rotating counterclockwise relative to clockwise is from -2.18 to 1.6.

[0071] In summary, the present invention reduces the deviation between the clockwise and counterclockwise rotation torques of the rotor by reducing the clockwise rotation torque of the rotor and increasing the counterclockwise rotation torque of the rotor, so that the torques of the two tend to be equal. Therefore, the change of phase current and the change of phase inductance reduce the clockwise rotation torque of the motor rotor and increase the counterclockwise rotation torque of the motor rotor.

[0072] Similarly, when the counterclockwise rotation torque of the motor rotor is large, the concept proposed by the present invention can also be used to effectively compensate for the torque deviation caused by the clockwise and counterclockwise rotation of the motor, that is, to achieve the above-mentioned offset angle ΔC in the opposite circumferential direction.

[0073] The exemplary implementation of the motor proposed in the present invention is described in detail above with reference to the preferred embodiments. However, those skilled in the art will appreciate that, without departing from the concept of the present invention, various modifications and variations can be made to the above-mentioned specific embodiments, and various technical features and structures proposed in the present invention can be combined in various ways without exceeding the scope of protection of the present invention.

Claims

1. A motor, comprising: a rotor assembly having a rotating shaft and permanent magnets disposed about the rotating shaft; as well as A stator assembly comprising: A first pole claw carrier, on which a plurality of first pole claws uniformly distributed in the circumferential direction and first pole claw grooves located between adjacent first pole claws are alternately arranged, the first pole claw carrier being in the form of a pole claw plate, the pole claw plate having the plurality of first pole claws bent toward one side along the rotation axis and uniformly distributed in the circumferential direction with the rotation axis as the center; A second pole claw bearing member, on which a plurality of second pole claws uniformly distributed along the circumferential direction and second pole claw grooves located between adjacent second pole claws are alternately arranged; a housing, the housing having a wall surrounding the plurality of first pole claws and the plurality of second pole claws in an assembled state of the stator assembly, and the wall being provided with a notch, wherein the first pole claw is inserted into the corresponding second pole claw slot, and the second pole claw is inserted into the corresponding first pole claw slot, so that when excited, at least one pole claw of the plurality of first pole claws and the plurality of second pole claws is configured such that the actual working center line along the axial direction is offset by an angle ΔC along the same circumferential direction as the center line of the corresponding pole claw slot; Each first pole claw has a first pole claw root connected to the first pole claw carrier, and the first pole claw has a first theoretical center line in the axial direction passing through the center of the first pole claw root; Each second pole claw has a second pole claw root connected to the second pole claw carrier, and the second pole claw has a second theoretical center line in the axial direction passing through the center of the second pole claw root; At least one of the plurality of first pole claws and the plurality of second pole claws is constructed to be asymmetric relative to its theoretical center line, so that when excited, the actual working center line of the at least one pole claw is offset from its theoretical center line by the angle ΔC.

2. The motor according to claim 1, wherein: A material removal portion is provided on one side of the theoretical center line of the at least one pole claw, so that the actual working center line of the at least one pole claw is offset from its theoretical center line by the angle ΔC.

3. The motor according to claim 2, wherein: The material removal is a cutaway portion provided at the top of the corresponding pole claw.

4. The motor according to claim 3, wherein: The cutting angle is an oblique angle or an arc angle, and the cutting angle width w is not greater than half of the width l of the pole claw top. The motor according to claim 4 , wherein the bevel angle is a 45 degree bevel angle or a 60 degree bevel angle.

6. The motor according to claim 1, wherein: An increased material portion is provided on one side of the theoretical center line of the at least one pole claw, so as to achieve that the actual working center line of the at least one pole claw is offset from its theoretical center line by the angle ΔC.

7. The electric machine according to any one of claims 1 to 6, wherein: At least one of the plurality of first pole claws is constructed to be asymmetric with respect to the corresponding first theoretical center line, and at least one of the plurality of second pole claws is constructed to be asymmetric with respect to the corresponding second theoretical center line, and for the at least one first pole claw and the at least one second pole claw, an actual working center line is offset from the corresponding theoretical center line by the angle ΔC along the same circumferential direction.

8. The electric machine according to any one of claims 1 to 6, wherein: At least two pole claws among the plurality of first pole claws and the plurality of second pole claws are configured asymmetrically with respect to a theoretical center line thereof.

9. The electric machine according to any one of claims 1 to 6, wherein: The theoretical center line of the pole claw coincides with the pole claw slot center line of the corresponding pole claw slot.

10. The electric machine according to any one of claims 1 to 6, wherein: The value of the angle ΔC is in the range of 1° to 3°.

11. The electric machine according to claim 10, wherein: The value of the angle ΔC is 2°.

12. The electric machine according to any one of claims 1 to 6, wherein: The second pole claw carrier is integral with the housing.

13. A motor, comprising: a rotor assembly having a rotating shaft and permanent magnets disposed about the rotating shaft; as well as A stator assembly comprising: A first pole claw carrier, on which a plurality of first pole claws uniformly distributed in the circumferential direction and first pole claw grooves located between adjacent first pole claws are alternately arranged, the first pole claw carrier being in the form of a pole claw plate, the pole claw plate having the plurality of first pole claws bent toward one side along the rotation axis and uniformly distributed in the circumferential direction with the rotation axis as the center; A second pole claw bearing member, on which a plurality of second pole claws uniformly distributed along the circumferential direction and second pole claw grooves located between adjacent second pole claws are alternately arranged; a housing, the housing having a wall surrounding the plurality of first pole claws and the plurality of second pole claws in an assembled state of the stator assembly, and the wall being provided with a notch, wherein the first pole claw is inserted into the corresponding second pole claw slot, and the second pole claw is inserted into the corresponding first pole claw slot, so that when excited, at least one pole claw of the plurality of first pole claws and the plurality of second pole claws is configured such that the actual working center line along the axial direction is offset by an angle ΔC along the same circumferential direction as the center line of the corresponding pole claw slot; The pole claw and the corresponding pole claw slot are assembled in a manner of angular offset along the circumferential direction, so that the theoretical center line of the pole claw is offset from the pole claw slot center of the corresponding pole claw slot by the angle ΔC.

14. The electric machine according to claim 13, wherein: The value of the angle ΔC is in the range of 1° to 3°.

15. The electric machine according to claim 14, wherein: The value of the angle ΔC is 2°.

16. An electric machine according to any one of claims 13 to 15, wherein: The second pole claw carrier is integral with the housing.

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