Rotor for driving motor

Abstract

The present disclosure provides a rotor for driving a motor, the rotor comprising a plurality of rotor cores, the rotor cores defining a plurality of slots, a permanent magnet being inserted into each slot, wherein the plurality of rotor cores comprise: a first core provided with fixing claws for fixing one surface of the permanent magnet and another surface relative to the one surface in an extension direction of the permanent magnet in an appropriate position; and a second core provided with fixing claws for fixing one surface of the permanent magnet and one of the other surface relative to the one surface in an extension direction of the permanent magnet in an appropriate position.

Description

Technical Field

[0001] The present disclosure relates to a rotor having stacked rotor cores, each having fixing claws for fixing permanent magnets in place. In particular, the present disclosure relates to a rotor for a drive motor, wherein the rotor cores have different numbers of fixing claws. Background Art

[0002] Drive motors used in environmentally friendly vehicles need to have high efficiency and output density. In particular, electric vehicles (EVs) need to obtain all vehicle power from the drive motor, thus further increasing the torque and output required from the drive motor. In the past, electric vehicles were limited to passenger cars, but now electric vehicles include sports cars, trucks, buses, etc. Therefore, the required torque and output have increased further. However, in order to provide high levels of torque and output within the limited space of the vehicle, the drive motor must be designed to be smaller.

[0003] Typically, embedded permanent magnet synchronous motors are used as drive motors for environmentally friendly vehicles. Permanent magnet synchronous motors are characterized by a structure in which permanent magnets are inserted into a rotor core and fixed in place by magnetic fixing claws. To miniaturize the drive motor, fixing claws are used to fix the permanent magnets in place. However, as the leakage of magnetic flux at the location where the fixing claws are provided increases, the torque density decreases, and thus the performance of the drive motor decreases. When the amount of permanent magnets used is increased to compensate for the reduced torque of the drive motor, the material cost of the drive motor increases, resulting in a decrease in cost competitiveness. When the amount of current is increased to compensate for the reduced torque of the drive motor, the cost of the inverter components increases, and thus the efficiency decreases. Summary of the Invention

[0004] An object of the present disclosure is to provide a rotor for a drive motor, which is capable of minimizing the number of fixing claws applied to the drive motor, thereby minimizing leakage of magnetic flux.

[0005] According to one aspect of the present disclosure, a rotor for a drive motor is provided. The rotor for the drive motor includes a plurality of rotor cores, the plurality of rotor cores defining a plurality of slots, each of which has a permanent magnet inserted therein, the plurality of rotor cores including a first core and a second core, the first core being provided with a fixing claw for fixing one surface of the permanent magnet and another surface relative to the one surface in an extending direction of the permanent magnet in an appropriate position, and the second core being provided with a fixing claw for fixing one of the one surface of the permanent magnet and another surface relative to the one surface in an extending direction of the permanent magnet in an appropriate position.

[0006] According to an aspect of the present disclosure, in the rotor, the one surface may be adjacent to a shaft hole defined in the rotor, and the other surface is a surface opposite to the one surface, and the second core may include a fixing claw for fixing the other surface of the permanent magnet in an appropriate position.

[0007] According to an aspect of the present disclosure, in the rotor, the fixing claws may be provided in one or more of the slots in the second core and thus may fix the other surface of the permanent magnet in place.

[0008] According to an aspect of the present disclosure, in the rotor, the fixing claw provided in the second core may be disposed not to contact one surface of the permanent magnet provided in each slot of the second core.

[0009] According to one aspect of the present disclosure, the rotor may further include a third core including a fixing claw for fixing in position the other surface of a permanent magnet inserted into each of one or more of the slots. The rotor may be configured to stack at least one or more first cores, at least one or more second cores, and at least one or more third cores.

[0010] According to one aspect of the present disclosure, in the rotor, the permanent magnet may include a pair of permanent magnet groups symmetrical with respect to the D axis of the drive motor, and the permanent magnet group may include two permanent magnet groups overlapping in a radial direction relative to the rotating shaft hole defined in the rotor.

[0011] According to one aspect of the present disclosure, in the rotor, the second core may include a fixing claw, which is arranged to contact the other surface of the first permanent magnet group adjacent to the rotating shaft hole, and the fixing claw is in contact with the other surface of the second permanent magnet group arranged in the opposite direction of the rotating shaft hole relative to the first permanent magnet group.

[0012] According to one aspect of the present disclosure, in the rotor, the second core may include a fixing claw which is configured to contact the other surface of the first permanent magnet group adjacent to the shaft hole, and the fixing claw of the second core may be configured not to contact the other surface of the second permanent magnet group which is arranged in a relative direction of the shaft hole relative to the first permanent magnet group.

[0013] According to an aspect of the present disclosure, in a rotor, first cores and second cores may be stacked in an extending direction of a rotation shaft of the rotor, and the rotor core may include at least one or more first cores.

[0014] According to an aspect of the present disclosure, in the rotor, the number of the second cores may be greater than the number of the first cores.

[0015] According to an aspect of the present disclosure, in the rotor, the number of fixing claws provided in the first core may be greater than the number of fixing claws provided in the second core.

[0016] According to an aspect of the present disclosure, in the rotor, an empty space defined after the permanent magnets are inserted into the slots is defined as a barrier, and the barrier may be filled with epoxy resin.

[0017] According to an aspect of the present disclosure, in the rotor, the first core may be disposed at an uppermost portion and a lowermost portion of the rotor core.

[0018] According to an aspect of the present disclosure, in the rotor, first cores and second cores may be alternately stacked.

[0019] According to an embodiment of the present disclosure, a rotor is configured such that a first core and a second core having different numbers of fixed claws are intermixed to minimize the number of fixed claws used in the rotor. Therefore, simply by minimizing the number of fixed claws, the rotor can secure the permanent magnets in place, and the number of fixed claws can be reduced, thereby minimizing leakage of magnetic flux that drives the motor.

[0020] According to an embodiment of the present disclosure, a second core is provided in the rotor, and the second fixing claw, which was located adjacent to the rotating shaft, is removed from the second core. This reduces magnetic flux leakage from the drive motor. Furthermore, first fixing claws, which are affected by the stress of the permanent magnets due to the rotation of the rotor, are provided in the first and second cores. This maintains the fixing force that secures the permanent magnets in place. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a diagram illustrating a stacking structure of a rotor core applied to a drive motor according to an embodiment of the present disclosure;

[0022] Figure 2 is a diagram illustrating an example of a rotor core according to an embodiment of the present disclosure;

[0023] Figure 3 is a diagram illustrating another example of a rotor core according to an embodiment of the present disclosure;

[0024] Figure 4 is a diagram illustrating an example of a stacking structure of a rotor core according to an embodiment of the present disclosure;

[0025] Figure 5 is a diagram illustrating another example of a rotor core according to an embodiment of the present disclosure;

[0026] Figure 6 is a diagram illustrating another example of a stacking structure of a rotor core according to an embodiment of the present disclosure; and

[0027] Figure 7 is a diagram illustrating another example of the stacking structure of the rotor core according to the embodiment of the present disclosure. DETAILED DESCRIPTION

[0028] The advantages and features of the present disclosure and the methods for achieving these advantages and features will become apparent from the accompanying drawings and the embodiments described in detail below. However, the present disclosure is not limited to the embodiments disclosed below and can be implemented in various different embodiments. The embodiments are provided to fully disclose the present disclosure and to enable those skilled in the art to clearly understand the scope of the present disclosure. However, the scope of the present disclosure should only be defined in the claims. The same reference numerals throughout the specification refer to the same components.

[0029] In addition, in order to distinguish between constituent elements having the same name, the terms first, second, etc. are used throughout this specification. In the following description, it is not necessary to impose any limitation on the order.

[0030] The present disclosure is described in detail in an illustrative manner. In addition, the above description is for the preferred embodiments of the present disclosure and can be implemented in various combinations, changes and environments. The present disclosure can be changed or modified within the scope of the inventive concept disclosed in this specification, the scope equivalent to the disclosed content described and / or the scope of the technology or knowledge in the art. The optimal requirements for realizing the technical ideas of the present disclosure are described with respect to the embodiments. Various changes required in the application fields and uses of the present disclosure are also possible. Therefore, the above detailed description of the present disclosure is not intended to impose any limitations on the disclosed embodiments. In addition, the claims should also be interpreted to cover other embodiments.

[0031] Figure 1 is a diagram illustrating a stacking structure of a rotor core applied to a drive motor according to an embodiment of the present disclosure.

[0032] Reference Figure 1 The rotor 1 can be configured such that the first cores 100a and the second cores 100b are mixed and stacked. The rotor 1 can be configured such that dozens or hundreds of first cores 100a and dozens or hundreds of second cores 100b are stacked. The first cores 100a and the second cores 100b are stacked along the extending direction of the rotation shaft inserted into the rotation shaft hole 50. The first cores 100a and the second cores 100b overlap in a direction perpendicular to the drawing.

[0033] Typically, the rotor cores constituting the rotor 1 have the same shape. However, according to an embodiment of the present disclosure, rotor cores having different shapes are stacked to constitute the rotor 1. The rotor cores (the first core 100a and the second core 100b) have a common slot, each of which has a permanent magnet inserted therein. However, the first core 100a and the second core 100b have different numbers of fixing claws for fixing the permanent magnets in place. Each of the first core 100a and the second core 100b has a fixing claw. However, the number of fixing claws provided in the first core 100a and the number of fixing claws provided in the second core 100b are different from each other. The fixing claws will be described in detail below.

[0034] Figure 2 is a diagram illustrating an example of a rotor core according to an embodiment of the present disclosure.

[0035] Reference Figure 1 and Figure 2 The first core 100a includes a plurality of slots 150a, 150b, 150c, and 150d, a plurality of permanent magnets 200a, 200b, 200c, and 200d, a plurality of first fixing claws 310a, 310b, 310c, and 310d, and a plurality of second fixing claws 320a, 320b, 320c, and 320d. Figure 2 The first core 100a in FIG. 1 is shown as constituting a part of one pole, and the four permanent magnets 200a, 200b, 200c, and 200d constitute one pole of the drive motor.

[0036] Grooves 150a, 150b, 150c, and 150d are formed in the first core 100a. Grooves 150a, 150b, 150c, and 150d represent spaces into which permanent magnets 200a, 200b, 200c, and 200d are inserted, and their shapes and quantities can be varied. According to the present embodiment, grooves 150a and 150d are combined to form a V-shaped shape, and grooves 150b and 150c are also combined to form a V-shaped shape. After permanent magnets 200a, 200b, 200c, and 200d are inserted into grooves 150a, 150b, 150c, and 150d, respectively, empty spaces may remain in grooves 150a, 150b, 150c, and 150d. Empty spaces defined after the permanent magnets 200a, 200b, 200c and 200d, the first fixing claws 310a, 310b, 310c and 310d and the second fixing claws 320a, 320b, 320c and 320d are respectively disposed in the slots 150a, 150b, 150c and 150d are barriers 155a, 155b, 155c, 155d, 157, 157a and 157d. The barriers 155a, 155b, 155c, 155d, 157, 157a, and 157d include first barriers 155a, 155b, 155c, and 155d defined above the permanent magnets 200a, 200b, 200c, and 200d, and second barriers 157, 157a, and 157d defined below the permanent magnets 200a, 200b, 200c, and 200d. Each of the first barriers 155a, 155b, 155c, and 155d is spaced apart from each other. Each of the second barriers 157, 157a, and 157d is spaced apart from each other. The first barriers 155a, 155b, 155c, and 155d and the second barriers 157a, 157, and 157d are spaced apart from each other. The barriers 155a, 155b, 155c, 155d, 157, 157a, and 157d are filled with epoxy resin or air, thereby minimizing the amount of leakage of magnetic flux generated in the permanent magnets 200a, 200b, 200c, and 200d through the first core 100a.

[0037] Four permanent magnets, namely permanent magnets 200a, 200b, 200c and 200d, are respectively arranged in slots 150a, 150b, 150c and 150d. The first permanent magnet 200a is inserted into the first slot 150a, the second permanent magnet 200b is inserted into the second slot 150b, the third permanent magnet 200c is inserted into the third slot 150c, and the fourth permanent magnet 200d is inserted into the fourth slot 150d. Each of the permanent magnets 200a, 200b, 200c and 200d has a first surface, a second surface, a third surface and a fourth surface.

[0038] For example, permanent magnets 200a, 200b, 200c, and 200d comprise a pair of permanent magnet groups. According to this embodiment, the first permanent magnet 200a and the fourth permanent magnet 200d form a pair of permanent magnets, and the second permanent magnet 200b and the third permanent magnet 200c form a pair of permanent magnets. That is, the pair of permanent magnets is arranged in a V-shape. Permanent magnets 200a, 200b, 200c, and 200d comprise a pair of permanent magnet groups symmetrical about the D-axis of the drive motor. The permanent magnet group includes two permanent magnet groups that overlap in the radial direction relative to the rotating shaft hole 50 defined in the rotor 1. The surfaces of the pair of permanent magnets facing each other are defined as first surfaces, and the surfaces opposite the first surfaces are defined as second surfaces. The D-axis is the axis that generates the magnetic flux of the drive motor and is defined in the space between the pair of permanent magnets. The Q-axis is an axis rotated 90 degrees counterclockwise from the D-axis and is defined in the space outside the pair of permanent magnets. The first surface refers to the inner surface based on the pair of permanent magnets, and the second surface refers to the outer surface based on the pair of permanent magnets. In addition, each of the permanent magnets 200a, 200b, 200c and 200d has a third surface and a fourth surface that are opposite to each other in the extension direction of the permanent magnets 200a, 200b, 200c and 200d. The fourth surface of each of the permanent magnets 200a, 200b, 200c and 200d is adjacent to the first barrier 155a, 155b, 155c and 155d respectively, and the third surface of each of the permanent magnets 200a, 200b, 200c and 200d is adjacent to the second barrier 157, 157a and 157d respectively.

[0039] The first fixing claws 310a, 310b, 310c, and 310d and the second fixing claws 320a, 320b, 320c, and 320d are respectively disposed in the slots 150a, 150b, 150c, and 150d. The first fixing claws 310a, 310b, 310c, and 310d and the second fixing claws 320a, 320b, 320c, and 320d guide the direction in which the permanent magnets 200a, 200b, 200c, and 200d are disposed, and the permanent magnets 200a, 200b, 200c, and 200d are fixed in appropriate positions within the slots 150a, 150b, 150c, and 150d, respectively. The first fixing claws 310a, 310b, 310c, and 310d contact one surface of the permanent magnets 200a, 200b, 200c, and 200d. The second fixing claws 320a, 320b, 320c and 320d are in contact with the other surface of the permanent magnets 200a, 200b, 200c and 200d, and the other surface is relative to a surface in the extension direction of the permanent magnets. Therefore, the permanent magnets 200a, 200b, 200c and 200d are fixed in place. In addition, the first fixing claws 310a, 310b, 310c and 310d and the second fixing claws 320a, 320b, 320c and 320d are respectively arranged on the other surface of the slots 150a, 150b, 150c and 150d that contacts the second surface of the permanent magnets 200a, 200b, 200c and 200d. Specifically, the first fixing claws 310a, 310b, 310c and 310d are in contact with the fourth surface of the permanent magnets 200a, 200b, 200c and 200d. The second fixing claws 320a, 320b, 320c, and 320d are in contact with the third surfaces of the permanent magnets 200a, 200b, 200c, and 200d. In addition, the first fixing claws 310a, 310b, 310c, and 310d are adjacent to the first barriers 155a, 155b, 155c, and 155d, respectively, and the second fixing claws 320a, 320b, 320c, and 320d are adjacent to the second barriers 157a, 157, and 157d, respectively.

[0040] For example, the first fixing claws 310a, 310b, 310c and 310d and the second fixing claws 320a, 320b, 320c and 320d are configured to protrude from the surfaces of the slots 150a, 150b, 150c and 150d that contact the second surfaces (external surfaces) of the permanent magnets 200a, 200b, 200c and 200d, respectively, toward the other surfaces of the slots 150a, 150b, 150c and 150d.

[0041] Figure 3 is a diagram illustrating another example of a rotor core according to an embodiment of the present disclosure.

[0042] Reference Figures 1 to 3, the second core 100b has a structure in which the second fixing claws 320a, 320b, 320c, and 320d are removed from the first core 100a. The second core 100b only has the first fixing claws 310a, 310b, 310c, and 310d. The first fixing claws 310a, 310b, 310c, and 310d contact at least one of the surfaces (third surface) and the other surface (fourth surface) of the permanent magnets 200a, 200b, 200c, and 200d in the direction of their extension. Therefore, the permanent magnets 200a, 200b, 200c, and 200d are fixed in place. Preferably, the first fixing claws 310a, 310b, 310c, and 310d contact the other surface (fourth surface) of the permanent magnets 200a, 200b, 200c, and 200d in the direction of their extension. That is, the first fixing claws 310a, 310b, 310c, and 310d are in contact with the other surface (fourth surface) of the permanent magnets 200a, 200b, 200c, and 200d, which is located on the outermost side relative to the rotation shaft hole 50. In other words, the surface in contact with the first fixing claws 310a, 310b, 310c, and 310d is the other surface of the permanent magnets 200a, 200b, 200c, and 200d, which is located farthest from the rotation shaft hole 50. Due to the rotation of the rotor 1, stress is generated in the permanent magnets 200a, 200b, 200c, and 200d in a direction away from the rotation shaft hole 50 (in a direction from the inner ends of the permanent magnets 200a, 200b, 200c, and 200d toward the outer ends). Therefore, the second core 100b secures the permanent magnets 200a, 200b, 200c, and 200d in place by the first securing claws 310a, 310b, 310c, and 310d, respectively, and withstands the stress generated by the permanent magnets 200a, 200b, 200c, and 200d. Conversely, stress is not applied in the direction from the outer ends of the permanent magnets 200a, 200b, 200c, and 200d toward their inner ends relative to the shaft hole 50. Therefore, even if the second securing claws 320a, 320b, 320c, and 320d are removed from the first securing claws 310a, 310b, 310c, and 310d and the second securing claws 320a, 320b, 320c, and 320d, the securing force securing the permanent magnets 200a, 200b, 200c, and 200d in place is maintained. The second core 100b according to an embodiment of the present disclosure has a structure in which the second fixing claws 320a, 320b, 320c, and 320d are removed to minimize leakage of magnetic flux while maintaining a fixing force fixing the permanent magnets 200a, 200b, 200c, and 200d in place.

[0043] Figure 4 is a diagram illustrating an example of a stacking structure of a rotor core according to an embodiment of the present disclosure. Figure 4 It is along Figure 2A cross-sectional view taken along line AA' in FIG.

[0044] Reference Figures 1 to 4 , the rotor 1 is configured with a mixed stack of a first core 100a and a second core 100b. Figure 2 The first core 100a is shown in FIG. Figure 3 The second core 100b is shown in FIG. The first core 100a has more fixing claws than the second core 100b.

[0045] The rotor 1 has a structure in which a large number of second cores 100b and a small number of first cores 100a are stacked. The rotor 1 includes at least one or more first cores 100a. The first core 100a includes a first fixing claw 310b and a second fixing claw 320b, and the second core 100b includes only the first fixing claw 310b.

[0046] Barrier 157 is filled with epoxy resin or air, thereby minimizing the amount of magnetic flux generated in permanent magnet 200b leaking through first core 100a and second core 100b. Since air and epoxy resin have lower transmittances than magnetic materials, barrier 157 minimizes leakage. For example, when the transmittance of air is defined as approximately 1, the transmittance of the iron that constitutes first core 100a and second core 100b is 280,000. In this case, magnetic flux leaks from the first and second fixed claws 310b, 320b of first core 100a, and the first fixed claw 310b of second core 100b. This results in a reduction in torque density, thereby degrading the performance of the drive motor.

[0047] The leaked magnetic flux is proportional to the transmittance, and the leaked magnetic flux is defined according to the following equation.

[0048]

[0049]

[0050] Wherein, Φ represents magnetic flux, F represents magnetomotive force, R represents magnetic resistance, l represents distance, A represents area, and μ represents transmittance. Distance and area refer to the length and area of ​​barrier 157.

[0051] According to an embodiment of the present disclosure, to minimize the number of fixing claws used in rotor 1, first core 100a and second core 100b are configured such that first fixing claw 310b and second fixing claw 320b are provided in first core 100a, and only first fixing claw 310b is provided in second core 100b. Furthermore, rotor 1 is configured by stacking a small number of first cores 100a having a relatively large number of fixing claws and a large number of second cores 100b having a relatively small number of fixing claws. Thus, rotor 1 secures permanent magnet 200b in place using only a minimal number of fixing claws, and the reduced number of fixing claws minimizes magnetic flux leakage.

[0052] Furthermore, according to an embodiment of the present disclosure, the rotor 1 is designed as follows: in order to support the permanent magnets 200a, 200b, 200c, and 200d during the rotation of the rotor 1, the first fixing claws 310a, 310b, 310c, and 310d are provided in each of the first core 100a and the second core 100b, and the second fixing claws 320a, 320b, 320c, and 320d, which are relatively less affected by stress, are removed as much as possible. In other words, the second fixing claws 320a, 320b, 320c, and 320d are removed from the second core 100b, thereby minimizing the leakage of magnetic flux passing through the first core 100a and the second core 100b.

[0053] Unlike the example described above, the first cores 100a and the second cores 100b are stacked in an alternating manner. Therefore, although the first cores 100a and the second cores 100b without the second fixing claws 320a, 320b, 320c and 320d are mixed and stacked, the permanent magnets 200a, 200b, 200c and 200d are fixed in place.

[0054] Figure 5 is a diagram illustrating another example of a rotor core according to an embodiment of the present disclosure. Figure 6 is a diagram illustrating another example of the stacking structure of the rotor core according to the embodiment of the present disclosure.

[0055] Reference Figures 1 to 3 、 Figure 5 and Figure 6A third core 100c having a different shape from the first and second cores 100a and 100b is provided. The third core 100c has a structure that removes the second fixing claws 320a, 320b, 320c, and 320d that secure one surface of the permanent magnets 200a, 200b, 200c, and 200d in place, and the first fixing claws 310b and 310c that secure the other surfaces of the second and third permanent magnets 200b and 200c in place. The third core 100c includes first fixing claws 310a and 310d that are disposed in slots 150a and 150d of the slots 150a, 150b, 150c, and 150d, respectively, to secure the permanent magnets 200a and 200d in place. However, the third core 100c does not include any other fixing claws, namely, the first fixing claws 310b and 310c provided in slots 150b and 150c of slots 150a, 150b, 150c, and 150d, respectively, to secure the permanent magnets 200b and 200c in place. That is, the third core 100c includes the first fixing claws 310a and 310d that contact the other surface of the first permanent magnet group 200a and 200d. However, the first fixing claws 310b and 310c that contact the other surface of the second permanent magnet group 200b and 200c are not provided. The second permanent magnet group 200b and 200c is provided in a direction opposite to the first permanent magnet group 200a and 200d in the rotation shaft hole 50.

[0056] The rotor 1 is configured by stacking at least one or more first cores 100a, at least one or more second cores 100b, and at least one or more third cores 100c. In this case, the number of stacked first cores 100a is smaller than the number of stacked second cores 100b and the number of stacked third cores 100c. The second cores 100b are arranged at the uppermost and lowermost portions of the rotor cores constituting the rotor 1.

[0057] According to an embodiment of the present disclosure, to form the rotor 1, a large number of second cores 100b and third cores 100c having relatively few fixing claws are stacked, and a small number of first cores 100a having relatively more fixing claws are stacked. When the rotor 1 according to the present disclosure is applied to a drive motor, the permanent magnets 200a, 200b, 200c, and 200d are fixed in place by providing a minimum number of fixing claws, and leakage of magnetic flux in the drive motor is minimized.

[0058] Figure 7 is a diagram illustrating another example of the stacking structure of the rotor core according to the embodiment of the present disclosure.

[0059] Reference Figure 1 、 Figure 2 and Figure 7The first core 100a is disposed at the top and bottom of the rotor core constituting the rotor 1. The top and bottom are determined based on the extending direction of the rotating shaft. The first core 100a includes all first fixing claws 310a, 310b, 310c, and 310d and all second fixing claws 320a, 320b, 320c, and 320d for securing the permanent magnets 200a, 200b, 200c, and 200d in place. The first core 100a is disposed at the top and bottom of the rotor core, thereby increasing the securing force holding the permanent magnets 200a, 200b, 200c, and 200d in place. Furthermore, the second core 100b is disposed between the first cores 100a, which are disposed at the top and bottom of the rotor core, thereby minimizing leakage of magnetic flux in the drive motor.

[0060] While the embodiments of the present disclosure have been described above with reference to the accompanying drawings, it is apparent to those skilled in the art that the present disclosure may be implemented in other embodiments without modifying the technical concepts and basic features. Therefore, it should be understood that the embodiments described above are illustrative rather than restrictive in every respect.

Claims

1. A rotor for a drive motor, the rotor comprising a plurality of rotor cores, each of the plurality of rotor cores defining a plurality of slots, a permanent magnet being inserted into each slot, wherein the plurality of rotor cores comprises: a first core including a plurality of fixing claws for fixing one surface of the permanent magnet and another surface in an extending direction of the permanent magnet in appropriate positions; as well as The second core does not include a fixing claw for fixing one surface of the permanent magnet in an appropriate position, but includes a plurality of fixing claws for fixing the other surface of the permanent magnet in an appropriate position relative to the one surface in the extending direction of the permanent magnet, The one surface is adjacent to a rotation shaft hole defined in the rotor, and the other surface is opposite to the one surface.

2. The rotor according to claim 1, wherein: The fixing claws are located in one or more of the slots in the second core and fix the other surface of the permanent magnet in place.

3. The rotor according to claim 1, wherein: The fixing claw in the second core does not contact the one surface of the permanent magnet provided in each slot in the second core.

4. The rotor according to claim 1, further comprising: a third core including a plurality of fixing claws for fixing the other surface of the permanent magnet in position, the permanent magnet being inserted into each of one or more of the slots, The rotor is configured to stack at least one or more first cores, at least one or more second cores, and at least one or more third cores.

5. The rotor according to claim 1, wherein The permanent magnet includes a pair of permanent magnet groups symmetrical with respect to the D axis of the drive motor, and The permanent magnet group includes two permanent magnet groups that overlap in a radial direction with respect to the rotation shaft hole defined in the rotor.

6. The rotor according to claim 5, wherein: The second core includes a fixing claw that contacts the other surface of the first permanent magnet group adjacent to the shaft hole, and the fixing claw contacts the other surface of the second permanent magnet group arranged in an opposite direction of the shaft hole relative to the first permanent magnet group.

7. The rotor according to claim 5, wherein: The second core includes a fixing claw that contacts the other surface of the first permanent magnet group adjacent to the rotation shaft hole, and The fixing claw of the second core does not contact the other surface of the second permanent magnet group provided in an opposite direction of the rotation shaft hole with respect to the first permanent magnet group.

8. The rotor according to claim 1, wherein The first core and the second core are stacked in an extending direction of the rotation axis of the rotor, and The rotor core includes at least one or more first cores.

9. The rotor according to claim 1, wherein: The number of the second cores is greater than the number of the first cores.

10. The rotor according to claim 1, wherein The number of the fixing claws in the first core is greater than the number of the fixing claws in the second core.

11. The rotor according to claim 1, wherein: The empty space defined by inserting the permanent magnet into the slot is defined as a barrier, and, The barrier is filled with epoxy resin.

12. The rotor according to claim 1, wherein The first core is disposed at the uppermost portion and the lowermost portion of the rotor core.

13. The rotor according to claim 1, wherein The first cores and the second cores are alternately stacked.

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