Abstract:
A mover and stator assembly of an electric machine includes at least one stator and at least one rotor. Each stator includes multiple magnetic components each including a first surface and a salient portion protruding from the first surface. The rotor includes multiple second magnetic components each including a second surface and a groove located on the second surface. The first surfaces face the second surfaces, and the width of each salient portion is less than that of each groove.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This non-provisional application claims priority under 35 U.S.C. §119(e) on Patent Application No. 61/817,515 filed in the United States on Apr. 30, 2013 and under 35 U.S.C. §119(a) on Patent Application No. 102138640 filed in Taiwan, R.O.C. on Oct. 25, 2013, the entire contents of which are hereby incorporated by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    This disclosure relates to a mover and stator assembly of electric machine. 
       BACKGROUND 
       [0003]    With the development of technology and the continuous growth of population in today&#39;s world, the demand for energy is certainly getting higher. In addition, with the heavy consumption of non-renewable energy, the cost for energy is getting higher as well. Therefore, in order to achieve energy saving and reduce energy cost, many countries have started to more strictly limit the usage of energy in many aspects. To reduce energy usage in factories, many laws and policies are established to encourage all the companies to increase their efficiency on production. As for motors which are usually responsible for more than 70% of total energy usage in factories, manufacturers are also trying to achieve better efficiency on them. Considering the many types of motor structures, the most common one is the induction motor. Furthermore, permanent-magnet motor and reluctance motor are also popular because of their simple structures, easiness to repair, and high efficiency. 
         [0004]    For induction motors, the primary way of enhancing the efficiency is to reduce the internal energy loss. The internal energy loss can be divided into five categories, including iron loss, rotor and stator&#39;s resistance loss, air loss, friction loss, and stray loss. To reduce the rotor and stator&#39;s resistance loss, one of the main focuses of development is to use copper as the material for the rotor. For permanent-magnet motor, the magnet plays a big role in the motor&#39;s performance. Especially with the development seeking high efficiency, portability, and high torque density nowadays, the development not only focuses on increasing the magnetic energy product of the magnet, but also tries to reduce magnetic loss and effectively guide the magnetic circuit. In the designs of mover and stator in traditional machines, due to the limitation of the shape of the magnet and the stamping process of the silicon-steel sheet, the surface magnetic field is usually higher at the edges of the magnet. Furthermore, normal structures of mover and stator are made of silicon-steel sheet and rare earth magnet (for example: Dysprosium). The cost of rare earth material and manufacturing module for manufacturing permanent-magnet is relatively high, so the total cost of the entire manufacturing process becomes even higher. 
         [0005]    Therefore, there is a need for a mover and stator assembly of electric machine that can increase the efficiency, reduce energy loss, and reduce the manufacturing cost. 
       SUMMARY 
       [0006]    According to an embodiment, a mover and stator assembly of electric machine comprises at least one stator and at least one rotor. Each of the at least one stator comprises a plurality of first magnetic parts, and each of the first magnetic parts comprises a first surface and a convex part protruding from the first surface. Each of the at least one rotor comprises a plurality of second magnetic parts, and each of the second magnetic parts comprises a second surface and a concave part set up at the second surface. The first surface and the second surface face each other. The width of each of the convex parts is smaller than the width of each of the concave parts. 
         [0007]    According to an embodiment, a mover and stator assembly of electric machine comprises at least one stator and at least one rotor. Each of the stators comprises a plurality of first magnetic parts, and each of the first magnetic parts comprises a first surface and a concave part set up at the first surface. Each of the rotors comprises a plurality of second magnetic parts, and each of the second magnetic parts comprises a second surface and a convex part protruding from the second surface. The first surface and the second surface face each other. The width of each of the convex parts is smaller than the width of each of the concave parts. 
         [0008]    According to an embodiment, a mover and stator assembly of electric machine comprises a stator and a moving part. The stator comprises a first magnetic part which further comprises a first surface and a convex part protruding from the first surface. The moving part comprises a second magnetic part which further comprises a second surface and a concave part set up at the second surface. The first surface and the second surface face each other. The width of the convex part is smaller than the width of the concave part. The convex part and the concave part are set up along the moving direction of the moving part. 
         [0009]    According to an embodiment, a mover and stator assembly of electric machine comprises a stator and a moving part. The stator comprises a first magnetic part which further comprises a first surface and a concave part set up at the first surface. The moving part comprises a second magnetic part which further comprises a second surface and a convex part protruding from the second surface. The first surface and the second surface face each other. The width of the convex part is smaller than the width of the concave part. The convex part and the concave part are set up along the moving direction of the moving part. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a perspective view of an example mover and stator assembly of electric machine in an embodiment. 
           [0011]      FIG. 2  is a perspective exploded diagram of the example mover and stator assembly of electric machine in an embodiment. 
           [0012]      FIG. 3  is a top view diagram of the example mover and stator assembly of electric machine in an embodiment. 
           [0013]      FIG. 4  is a cutaway diagram of  FIG. 3  along the line  4 - 4 . 
           [0014]      FIG. 5A  is a partial enlarged cutaway diagram of the example mover and stator assembly of electric machine in  FIG. 4 . 
           [0015]      FIG. 5B  is a partial enlarged cutaway diagram of an example mover and stator assembly of electric machine in an embodiment. 
           [0016]      FIG. 6  is a partial enlarged cutaway diagram of an example mover and stator assembly of electric machine in an embodiment. 
           [0017]      FIG. 7  is a partial cutaway diagram of an example mover and stator assembly of electric machine in an embodiment. 
           [0018]      FIGS. 8A and 8B  are partial cutaway diagrams of an example mover and stator assembly of electric machine in an embodiment. 
           [0019]      FIGS. 9A ,  9 B,  9 C,  9 D,  9 E,  9 F, and  10  are cutaway diagrams of an example convex part and an example concave part in an embodiment. 
           [0020]      FIGS. 11A ,  11 B,  11 C,  11 D,  11 E, and  11 F are cutaway diagrams of an example convex part in an embodiment. 
           [0021]      FIG. 12  is a perspective view of an example mover and stator assembly of electric machine in an embodiment. 
           [0022]      FIG. 13  a perspective exploded diagram of the example mover and stator assembly of electric machine in an embodiment. 
           [0023]      FIG. 14  is a top view diagram of the example mover and stator assembly of electric machine in an embodiment. 
           [0024]      FIG. 15  is a cutaway diagram of  FIG. 14  along the line  15 - 15 . 
           [0025]      FIG. 16A  is a partial enlarged cutaway diagram of the example mover and stator assembly of electric machine in  FIG. 15 . 
           [0026]      FIGS. 16B ,  16 C,  17 A, and  17 B are partial enlarged cutaway diagrams of an example mover and stator assembly of electric machine in an embodiment. 
           [0027]      FIG. 18  is a perspective view of an example mover and stator assembly of electric machine in an embodiment. 
           [0028]      FIGS. 19A and 19B  are perspective diagrams of an example mover and stator assembly of electric machine in an embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0029]    In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing. 
         [0030]    The disclosure herein provides a mover and stator assembly of electric machine used for receiving electric energy. Through electromagnetic effects, the mover may move or rotate along the stator to generate mechanical energy. The mover may be a rotor which rotates relatively to the stator; the mover may also be a moving part which moves linearly relatively to the stator. Furthermore, electric machine may be induction motor, reluctance motor, permanent-magnet brushless motor, and linear moving assembly. However, the application of the mover and stator assembly herein does not have any limitations on the disclosure. 
         [0031]    Referring to  FIG. 1 ,  FIG. 2 , and  FIG. 3 ,  FIG. 1  is a perspective of an example mover and stator assembly of electric machine in an embodiment.  FIG. 2  is a perspective exploded diagram of the example mover and stator assembly of electric machine in an embodiment.  FIG. 3  is a top view diagram of the example mover and stator assembly of electric machine in an embodiment. According to the embodiment, the mover and stator assembly of electric machine  1  is a rotor and stator assembly comprising two stators  2 ,  2 ′ and one rotor  3 . The rotor  3  is between the two stators  2 ,  2 ′ and rotates relatively to the two stators  2 ,  2 ′. In the embodiment, the rotor and stator assembly is applied to axial electric motor. 
         [0032]    Referring to  FIG. 1 ,  FIG. 2 ,  FIG. 3 ,  FIG. 4 , and  FIG. 5A ,  FIG. 4  is a cutaway diagram of  FIG. 3  along the line  4 - 4 .  FIG. 5A  is a partial enlarged cutaway diagram of the example mover and stator assembly of electric machine in  FIG. 4 . For example, Stator  2  comprises several first magnetic parts  20  and a first shell  23 . The first magnetic parts  20  form a circular structure with the rotation axis A of the rotor  3  being the center of the circle. Each of the first magnetic parts  20  has a first surface  211  and two convex parts  212  protruding from the first surface  211 . All of the first surfaces  211  face the same direction and the convex parts  212  are placed along the circular direction of the rotation axis A to form two circular troughs. In the embodiment, the normal vector of the first surface  211  is parallel to the rotation axis A. Similarly, stator  2 ′ comprises several first magnetic parts  20 ′ and a second shell  24 . In this embodiment, first magnetic part  20 ,  20 ′ each comprises a magnetic conductive part  21 ,  21 ′ and a solenoid  22 ,  22 ′. Solenoid  22 ,  22 ′ each coils around the magnetic conductive parts  21 ,  21 ′ and the magnetic conductive parts  21 ,  21 ′ each has the first surface  211 ,  211 ′ and the convex parts  212 ,  212 ′ set up at the first surface  211 ,  211 ′, as described above. In other words, the first magnetic parts  20 ,  20 ′ may be electromagnet. Also, the number of the convex part  212  and concave part  311  described herein do not have any limitation on the disclosure. In other embodiments, the number of the convex part  212  and concave part  311  may be one or greater than two. 
         [0033]    The structure of rotor  3  is illustrated below. The rotor  3  comprises several second magnetic parts  31  surrounding a rotation shaft  32 . Each of the second magnetic parts  31  has a second surface  312 , a third surface  314 , two concave parts  311  set up at the second surface  312 , and two concave parts  311 ′ set up at the third surface  314 . The second surface  312  and the third surface  314  are located on the opposite sides of the rotor  3 . The second surfaces  312  of the second magnetic parts all face the first surfaces  211  of the magnetic conductive parts  21 , and the third surfaces  314  all face the first surfaces  211 ′ of the magnetic conductive parts  21 ′. In this embodiment and some other embodiments, the normal vector of the first surface  211  towards the second surface  312  and the normal vector of the first surface  211 ′ towards the third surface  314  are both parallel to the rotation axis A of the rotor  3 . Moreover, the concave parts  311  are placed along the circular direction of the rotor  3  with the rotation axis A being the center of circle to form a circular trough  3111 . When the rotor  3  rotates relatively to stator  2 , the concave parts  311  may rotate relatively to the convex parts  212  and the projections of the convex parts  212  to the rotor  3  in the direction parallel to the rotation axis A all lie inside the circular trough  3111 . Referring to  FIG. 5A , the width of each of the convex parts  212  is smaller than the width of each of the concave parts  311 . Each of the concave parts  311  has a bottom surface  3112  and a first side-wall  3113  facing a second side-wall  3114 . Each of the convex parts  212  has a top surface  2121  and a first side-part  2122  facing a second side-part  2123 . The bottom surface  3112  of each of the concave parts  311  faces the top surface  2121  of each of the corresponding convex parts  212 . The first side-wall  3113  and the second side-wall  3114  each connects with the corresponding side of the bottom surface  3112 , and the first side-part  2122  and the second side-part  2123  each connects with the corresponding side of the top surface  2121 . The first side-wall  3113  corresponds to the first side-part  2122  and the second side-wall  3114  corresponds to the second side-part  2123 . Therefore, the shape of cross-section of the convex parts  212  and the concave parts  311  in  FIG. 5A  is rectangle. In this embodiment, the concave parts  311  may rotate along the circular convex trough composed by the corresponding convex parts  212 . Furthermore, there is a perpendicular distance D1 between the bottom surface  3112  and the top surface  2121 . There is also a perpendicular distance D2 between the first side-part  2122  and the first side-wall  3113  and between the second side-part  2123  and the second side-wall  3114 . In this embodiment, the perpendicular distance D1 equals to the perpendicular distance D2. However, in other embodiments, the perpendicular distance D1 may not equal to the perpendicular distance D2. Also, in this embodiment, the convex parts  212  do not fall into the space of concave parts  311 , which is the space between the top surface  2121  at the second surface  312  and the bottom surface  3112 . 
         [0034]    However, the convex parts  212  not falling into the space of concave parts  311  does not try to have any limitation on the disclosure. Please refer to  FIG. 5B , which is a partial enlarged cutaway diagram of an example mover and stator assembly of electric machine in an embodiment. In this embodiment, the convex parts  212  do fall into the space of the concave parts  311  formed by the bottom surface  3112 , the first side-wall  3113 , and the second side-wall  3114 . In other words, the perpendicular distance D3 from the bottom surface  3112  of the concave parts  311  to the top surface  2121  of the convex parts  212  is smaller than the depth d1 of the concave parts  311 . 
         [0035]    Referring to  FIG. 4  and  FIG. 5A , concave parts  311 ,  311 ′ each faces convex parts  212 ,  212 ′, wherein the distances from the rotation shaft  32  to concave parts  311  and concave parts  311 ′ are different. Similarly, the distances from the rotation shaft  32  to convex parts  212  and convex parts  212 ′ are different. In other words, the corresponding formation of the concave parts  311 ,  311 ′ and the convex parts  212 ,  212 ′ is separately set up according to the radial direction of the rotation shaft  32 . 
         [0036]    In this disclosure, each of the second magnetic parts  31  may be a permanent magnet or a magnetic conductive part. When the second magnetic part  31  is a magnetic conductive part, the magnetic conductive part is silicon-steel sheet. Or the material of the magnetic conductive part is soft magnetic composite (SMC) material. 
         [0037]    In the above embodiment, the stator  2  disclosed has convex parts  212  and the rotor  3  disclosed has concave parts  311 , However, in other embodiments, the stator  2  may have concave parts and the rotor  3  may have convex parts. Please refer to  FIG. 6 , which is a partial enlarged cutaway diagram of an example mover and stator assembly of electric machine in an embodiment. Stator  2 ,  2 ′ each has concave parts  213 ,  213 ′ and rotor  3  has convex parts  313 ,  313 ′ locating on the opposite sides respectively. Concave parts  213 ,  213 ′ each face convex parts  313 ,  313 ′. For example, the concave part  213  has a bottom surface  2131 , a first side-wall  2132 , and a second side-wall  2133 . The convex part  313  has a top surface  3131 , a first side-part  3132 , and a second side-part  3133 . The top surface  3131  faces the bottom surface  2131 , and the first side-wall  2132  and the second side-wall  2133  corresponds to the first side-part  3132  and the second side-part  3133  respectively. The distance between the first side-wall  2132  and the second side-wall  2133  and the distance between the first side-part  3132  and the second side-part  3133  both equal to perpendicular distance D4. The distance between the top surface  3131  and the bottom surface  2131  equals to perpendicular distance D5. Perpendicular distance D4 may be equal to, smaller, or bigger than perpendicular distance D5. 
         [0038]    In the above embodiments, the method of placing rotor  3  between two stators  2 ,  2 ′ does not try to have any limitations on the disclosure. Please refer to  FIG. 7 , which is a partial cutaway diagram of an example mover and stator assembly of electric machine in an embodiment. This embodiment is similar to the embodiment described above. In this embodiment, the mover and stator assembly of electric machine  1  only comprises a stator  2  and a rotor  3 . The stator  2  comprises a magnetic conductive part  21  and a first shell  23 . The stator  2  is located on one side of the rotor  3 , which means the rotor  3  is on the opposite side of the first shell  23 . Moreover, the magnetic conductive part  21  has two convex parts  212  and the rotor  3  has two concave parts  313 . The two convex parts  212  and the two concave parts  313  face each other respectively. Thus, when the rotor  3  rotates relatively to the stator  2 , the concave parts rotates relatively to the convex parts  212  as well, thereby achieving the increase of rotation torque. 
         [0039]    The illustration below has several convex and concave parts with different gaps in between. Please refer to  FIG. 8A , which is a partial cutaway diagram of an example mover and stator assembly of electric machine in an embodiment. The embodiment in  FIG. 8A  is similar to the embodiment in  FIG. 7 . In this embodiment, the first magnetic part  20  of the stator  2  has several convex parts  212 . The convex parts  212  comprise a first convex part  212   a , a second convex part  212   b , and a third convex part  212   c  placed in the outward direction of the rotation axis A of the rotor  3  accordingly. The distance from the first convex part  212   a  to the second convex part  212   b  is different from the distance from the second convex part  212   b  to the third convex part  212   c . The second magnetic part  31  of the rotor  3  has several concave parts  311 . The concave parts  311  comprise a first concave part  311   a , a second concave part  311   b , and a third concave part  311   c  placed in the outward direction of the rotation axis A of the rotor  3  accordingly. The distance from the first concave part  311   a  to the second concave part  311   b  is different from the distance from the second concave part  311   b  to the third concave  311   c . In this embodiment, the first convex part  212   a , the second convex part  213   b , and the third convex part  212   c  have three first side-parts  2122   a ,  2122   b , and  2122   c  respectively. The first side-parts  2122   a ,  2122   b , and  2122   c  all face the rotation axis (on the left side of the figure). The distance between the first side-parts  2122   a ,  2122   b  and the distance between the first side-parts  2122   a ,  2122   c  are different. Moreover, the first concave part  311   a , the second concave part  311   b , and the third concave part  311   c  have three first side-walls  3113   a ,  3113   b , and  3113   c . The first side-walls  3113   a ,  3113   b , and  3113   c  all face the rotation axis. The distance between the first side-walls  3113   a ,  3113   b  and the distance between the first side-walls  3113   b ,  3113   c  are different. However, in other embodiments, the distance from the first convex part  212   a  to the second convex part  212   b  equals to the distance from the second convex part  212   b  to the third convex part  212   c ; the distance from the first concave part  311   a  to the second concave part  311   b  may also equal to the distance from the second concave part  311   b  to the third concave part  311   c . Therefore, when the rotor  3  rotates relatively to the stator  2 , the first concave part  311   a , the second concave part  311   b , and the third concave part  311   c  also rotate relatively to the first convex part  212   a , the second convex part  212   b , and the third convex part  212   c  respectively, thereby achieving the increase of rotation torque. 
         [0040]    The gaps between the several concave parts of the stator  2  and the several convex parts of the rotor  3  are not the same. Please refer to  FIG. 8B , which is a partial cutaway diagram of an example mover and stator assembly of electric machine in an embodiment. This embodiment is similar to the embodiment in  FIG. 6 . In this embodiment, the magnetic conductive part  21  of the first magnetic part of the stator  2  has a first concave part  213   a , a second concave part  213   b , and a third concave part  213   c . The first concave part  213   a , the second concave part  213   b , and the third concave part  213   c  have a first side-wall  2132   a ,  2132   b , and  2132   c  respectively. Rotor  3  has a first convex part  313   a , a second convex part  313   b , and a third convex part  313   c . The first convex part  313   a , the second convex part  313   b , and the third convex part  313   c  have a side-part  3132   a ,  3132   b , and  3132   c  respectively. In this embodiment, the distance between the first concave part  213   a  and the second concave part  213   b  is different from the distance between the second concave part  213   b  and the third concave part  213   c , so the distance between the first side-walls  2132   a ,  2132   b  is also different from the distance between the first side-walls  2132   b ,  2132   c . Similarly, the distance between the first convex part  313   a  and the second convex part  313   b  is different from the distance between the second convex part  313   b  and the third convex part  313   c , so the distance between the first side-parts  3132   a ,  3132   b  is different from the distance between the first side-parts  3132   b ,  3132   c . In other embodiments, the distance between the first concave part  213   a  and the second concave part  213   b  may equal to the distance between the second concave part  213   b  and the third concave part  213   c ; the distance between the first convex part  313   a  and the second convex part  313   b  may also equal to the distance between the second convex part  313   b  and the third convex part  313   c.    
         [0041]    The cross-sectional shape of the convex and concave parts described above is rectangle, but it does not intend to have any limitations on the disclosure and may be modified accordingly.  FIGS. 9A ,  9 B,  9 C,  9 D,  9 E,  9 F, and  10  are cutaway diagrams of an example convex part and an example concave part in an embodiment. In  FIG. 9A , the cross-sectional shape of convex parts  212  is a semicircle, and the cross-sectional shape of the concave part  311  is a circular arc (the area is smaller than semicircle). The center of circle of the convex parts  212  and the concave parts  311  are located on the extended surface of the first surface  211 , so the convex parts  212  and the concave parts  311  have the same center of circle. Moreover, the perpendicular distance D6 of the convex parts  212  and the concave parts  311  is smaller than the depth d2 of the concave parts  311 , so part of the volume of the convex parts  212  are inside the concave parts  311 . In  FIG. 9B , the cross-sectional shape of the convex part  212  is a circular arc, and the cross-sectional shape of the concave part  311  is also a circular arc. The centers of circle of the convex parts  212  are located inside the first magnetic parts, and the centers of circle of the concave parts  311  are located on the extended surface of the first surface  211 . Thus, the center of circle of the convex parts  212  and the concave parts  311  are different in location. In  FIG. 9C , the cross-sectional shapes of the convex parts  212  and the concave parts  311  are both oval shapes. In  FIG. 9D , the cross-sectional shape of the convex part  212  is a semicircle, and the cross-sectional shape of the concave part is an oval shape. In  FIG. 9E , the cross-sectional shape of the convex part  212  is an oval shape, and the cross-sectional shape of the concave part  311  is a circular arc. The center of circle of the concave parts  311  is located on the extended surface of the first surface  211 . In  FIG. 9F , the cross-sectional shape of the convex part  212  is a cylinder, and the cross-sectional shape of the concave part  311  is a semicircle. The center of circle of the concave parts  311  is located at the same location of the center of circle of the cylinder. Moreover, in other embodiments, when the magnetic conductive part  21  has concave part  213  and the second magnetic part  31  has convex part  313 , the cross-sectional shapes of concave part  213  and convex part  313  may be the shapes described above in  FIGS. 9A ,  9 B,  9 C,  9 D,  9 E, and  9 F. For example, in  FIG. 10 , the cross-sectional shape of the concave part  213  is an oval shape, and the cross-sectional shape of the convex part  313  is a semicircle. Therefore, the cross-sectional shapes of the convex parts and concave parts described above may be semicircle, oval shape, circular arc, cylinder, or other shapes. The center of circle of convex part and concave part or the length of the cylinder may be modified accordingly. 
         [0042]      FIGS. 11A ,  11 B,  11 C,  11 D,  11 E, and  11 F are cutaway diagrams of an example convex part in an embodiment. The cross-sectional shape of convex part is not limited to be the shapes described above. In  FIG. 11A , the cross-sectional shape of the convex part  212  is an isosceles triangle and the top surface  2121  is the vertex of an acute angle. In  FIG. 11B , the cross-sectional shape of the convex part  212  is a right triangle, so the surface of the second side-part  2123  is perpendicular to the first surface  211  and the surface of the first side-part  2122  forms an acute angle with the first surface  211 . In  FIG. 11C , the cross-sectional shape of the convex part  212  is a isosceles trapezoid, so the first side-part  2122  and the second side-part  2123  are both symmetrical to the top surface  2121  whose surface is parallel to the first surface  211 . In  FIG. 11D , the cross-sectional shape of the convex part is an isosceles triangle, so this embodiment is similar to the embodiment in  FIG. 11A  except that the top surface  2121  is a chamfered surface. In  FIG. 11E , the cross-sectional shape of the convex part  212  is a right trapezoid, so the surface of the first side-part  2122  of the convex part  212  is perpendicular to the first surface  211  and the surface of the second side-part  2123  forms an acute angle with the first surface  211 . The surface of the top surface  2121  is parallel to the first surface  211 . In  FIG. 11F , the cross-sectional shape of the convex part  212  is a right trapezoid with chamfered top surface, so comparing to  FIG. 11E , the top surface  2121  of this embodiment is chamfered (also called filleted). The cross-sectional shape of the convex part  212  and the placements of the top surface  2121 , the first side-part  2122 , the second side-part  2123 , and the first surface  211  may all be modified accordingly. Moreover, similar to the convex part described above, the cross sectional shape of the concave part of the embodiment (not shown in FIGs) may be rectangle, circular arc, semicircle, cylinder, isosceles triangle with chamfered top surface, isosceles triangle, right triangle, isosceles trapezoid, right trapezoid, or isosceles trapezoid with chamfered top surface according to the requirement. 
         [0043]    The above description is about the axial mover and stator assembly of electric machine  1 . The description below is about the radial mover and stator assembly of electric machine. Referring to  FIGS. 12 ,  13 ,  14 ,  15 , and  16 A,  FIG. 12  is a perspective view of an example mover and stator assembly of electric machine in an embodiment.  FIG. 13  a perspective exploded diagram of the example mover and stator assembly of electric machine in an embodiment.  FIG. 14  is a top view diagram of the example mover and stator assembly of electric machine in an embodiment.  FIG. 15  is a cutaway diagram of  FIG. 14  along the line  15 - 15 .  FIG. 16A  is a partial enlarged cutaway diagram of the example mover and stator assembly of electric machine in  FIG. 15 . In this embodiment, a mover and stator assembly of electric machine  1 ′ comprises a stator  2  and a rotor  3 . The stator  2  radially surrounds the rotor  3 . When in motion, the rotor  3  rotates relatively to the stator  2  along the rotation axis A. The stator  2  comprises several first magnetic parts  20 . Each of the first magnetic parts  20  comprises a magnetic conductive part  21  and a solenoid  22 . Each of the magnetic conductive parts  21  has a first surface  211  and two convex parts  212  set up at the first surface  211 . The solenoids  22  are coiled around the magnetic conductive parts  21  respectively. In this embodiment, the rotor  3  comprises several second magnetic parts  31  and a rotation shaft  32 . The rotation shaft  32  is surrounded by the several second magnetic parts  31 . Each of the second magnetic parts  31  has a second surface  312  and two concave parts  311  set up at the second surface  312 . Each of the second surfaces  312  of the second magnetic parts  31  faces outward. The first surface  211  and its two convex parts  212  face the second surface  312  and its two concave parts  311 . In other words, the direction from the first surface  211  to the second surface  312  is perpendicular to the rotation axis A of the rotor  3 . Also, the number of the first magnetic parts  20  and the number of the second magnetic parts  31  are not the same. 
         [0044]    The description below is about the structure of the first magnetic part  20  and the second magnetic part  31  of the mover and stator assembly of electric machine  1 ′. Referring to  FIG. 15  and  FIG. 16A , each of the convex parts  212  of the magnetic conductive parts  21  has a top surface  2121 , a first side-part  2122 , and a second side-part  2123 . The two sides of the top surface  2121  connect to the first side-part  2122  and the second side-part  2123 . The first side-part  2122  and the second side-part  2123  connect to the first surface  211 . The concave part  311  has a bottom surface  3112 , a first side-wall  3113 , and a second side-wall  3114 . The two sides of the first side-wall  3113  and the second side-wall  3114  connect to the bottom surface  3112  and the second surface  312  respectively. In this embodiment, the perpendicular distance D7 of the top surface  2121  and the bottom surface  3112  equals to the perpendicular distance D8 of the first side-part  2122  and the first side-wall  3113 . However, in other embodiments, the perpendicular distance D7 of the top surface  2121  and the bottom surface  3112  may be greater or smaller than the perpendicular distance D8 of the first side-part  2122  and the first side-wall  3113 . Moreover, in this embodiment, the top surface  2121  is located on the extending surface of the second surface  312 , so the convex part  212  is not located inside the concave part  311 . 
         [0045]    In other embodiments, Please refer to  FIG. 16B , which is a partial enlarged cutaway diagrams of an example mover and stator assembly of electric machine in an embodiment. The perpendicular distance D9 of the top surface  2121  and the bottom surface  3112  is smaller than the depth d3 of the concave part  311 , so part of the volume of the convex part  212  is located inside the concave part  311 , thereby achieving the increase of rotation torque. 
         [0046]    The first magnetic part  20  and the second magnetic part  31  described above only have two convex parts  212  and two concave parts  311  respectively, but the number of convex parts  212  and concave parts  311  do not have any limitations on the disclosure.  FIG. 16C  is a partial enlarged cutaway diagram of an example mover and stator assembly of electric machine in an embodiment. In this embodiment, each of the stators  2  comprises a first convex part  212   a , a second convex part  212   b , and a three convex part  212   c . The distance between the first convex part  212   a  and the second convex part  212   b  is different from the distance between the second convex part  212   b  and the third convex part  212   c . Each of the second magnetic parts  31  of the rotor  3  comprises a first concave part  311   a , a second concave part  311   b , and a third concave part  311   c . The distance between the first concave part  311   a  and the second concave part  311   b  is different from the distance between the second concave part  311   b  and the third concave part  311   c . In this embodiment, the first convex part  212   a , the second convex part  212   b , and the third convex part  212   c  each respectively have a first side-part  2122   a ,  2122   b , and  2122   c . The first side-parts  2122   a ,  2122   b , and  2122   c  all face the same direction. The distance between the first side-part  2122   a  and  2122   b  is different from the distance between the first side-part  2122   b  and  2122   c . Similarly, the first concave part  311   a , the second concave part  311   b , and the third concave part  311   c  each respectively has a first side-wall  3113   a ,  3113   b , and  3113   c . The first side-walls  3113   a ,  3113   b , and  3113   c  all face the same direction. The distance between the first side-wall  3113   a  and  3113   b  is different from the distance between the first side-wall  3113   b  and  3113   c.    
         [0047]    However, in other embodiments, the distance between the first convex part  212   a  and the second convex part  212   b  equals to the distance between the second convex part  212   b  and the third convex part  212   c ; the distance between the first concave part  311   a  and the second concave part  311   b  equals to the distance between the second concave part  311   b  and the third concave part  311   c.    
         [0048]    In the description of the mover and stator assembly of electric machine  1 ′ above, the stator  2  comprises the convex parts  212  and the rotor  3  comprises the concave parts  311 . However, in other embodiments, the stator  2  may comprise concave parts and rotor  3  may comprise convex parts. Please refer to  FIG. 17A , which is a partial enlarged cutaway diagram of an example mover and stator assembly of electric machine in an embodiment. This embodiment is similar to the embodiments described above. In the mover and stator assembly of electric machine  1 ′, each of the first magnetic parts  20  of the stator  2  has a first surface  211  and a concave part  213  set up at the first surface  211 . Each of the second magnetic parts  31  of the rotor  3  has a second surface  312  and a convex part  313  protruding from the second surface  312 . The first surface  211  and the second surface  312  face each other. The width of each of the convex parts  313  is smaller than the width of each of the concave parts  213 . In this embodiment, each of the concave parts  213  has a bottom surface  2131 , a first side-wall  2132 , and a second side-wall  2133 ; each of the convex parts  313  has a top surface  3131 , a first side-part  3132 , and a second side-part  3133 . In this embodiment, the perpendicular distance D10 from the top surface  3131  of the convex part  313  to the bottom surface  2131  of the concave part  213  equals to the perpendicular distance D11 from the first side-wall  2132  to the first side-part  3132 . Moreover, the convex part  313  is not inserted inside the concave part  213 . 
         [0049]    Also, in other embodiments, the perpendicular distance D10 from the top surface  3131  of the convex part  313  to the bottom surface  2131  of the concave part  213  is different from the perpendicular distance D11 from the first side-wall  2132  to the first side-part  3132 . In other embodiments, the top surface  3131  of the convex part  313  is between the bottom surface  2131  of the concave part  213  and the first surface  211 , so part of the volume of the convex part  212  is located inside the concave part  213 . 
         [0050]    The number of convex parts  313  and concave parts  213  described above is not to have any limitations on the disclosure.  FIG. 17B  is a partial enlarged cutaway diagram of an example mover and stator assembly of electric machine in an embodiment. This embodiment is similar to the embodiment of  FIG. 16B  and  FIG. 17A . Each of the first magnetic parts  20  comprises a first concave part  213   a , a second concave part  213   b , and a third concave part  213   c . The distance from the first concave part  213   a  to the second concave part  213   b  is different to the distance from the second concave part  213   b  to the third concave part  213   c . Each of the second magnetic parts  31  comprises a first convex part  313   a , a second convex part  313   b , and a third convex part  313   c . The distance from the first convex part  313   a  to the second convex part  313   b  is different to the distance from the second convex part  313   b  to the third convex part  313   c . In this embodiment, the first concave part  213   a , the second concave part  213   b , and the third concave part  213   c  each respectively has a first side-wall  2132   a ,  2132   b , and  2132   c . The first side-walls  2132   a ,  2132   b , and  2132   c  all face the same direction. The distance between the first side-wall  2132   a  and  2132   b  is different from the distance between the first side-wall  2132   b  and  2132   c . Similarly, the first convex part  313   a , the second convex part  313   b , and the third convex part  313   c  each respectively has a first side-part  3132   a ,  3132   b , and  3132   c . The first side-parts  3132   a ,  3132   b , and  3132   c  all face the same direction. The distance between the first side-part  3132   a  and  3132   b  is different from the distance between the first side-part  3132   b  and  3132   c.    
         [0051]    However, in other embodiments, the distance from the first concave part  213   a  to the second concave part  213   b  may equal to the distance from the second concave part  213   b  to the third concave part  213   c ; the distance from the first convex part  313   a  to the second convex part  313   b  may also equal to the distance from the second convex part  313   b  to the third convex part  313   c.    
         [0052]    The simulation analysis of the Experimental Group 1 described below is about the axial structure of the single stator  2  and single rotor  3  in  FIG. 7 . This mover and stator assembly of electric machine  1  uses the permanent magnet axial gap motor. The external diameter of the rotation shaft  32  is 14 mm and the external diameter of the rotor  3  is 24 mm. The electric energy is inputted by 3 phase direct current (dc) voltage with the rated power being 80 Watts. Magnet Volume is the volume of the magnet inside the magnetic conductive part of the rotor. Total Thickness includes the stator  2  and the rotor  3  of the mover and stator assembly of electric machine. Magnetic Flux Density is the total magnetic flux through the gaps of the mover and stator assembly of electric machine  1 . Weighted Axial Magnetic Flux Density is the magnetic flux of the single direction along the rotation axis A. Torque is the torque outputted by the rotor  3 . Control Group 1 and Control Group 2 are the simulation analysis of the mover and stator assemblies of electric machine in the prior art, so Control Group 1 and Control Group 2 do not have the convex and concave parts disclosed in this disclosure. Moreover, Control Group 1 has the same stator volume of Control Group 2. Control Group 2 has the same magnet volume as the Experimental Group 1. The columns of volume, thickness, magnetic flux, torque, and torque density difference below are comparisons of Experimental Group 1 to Control Group 1 and Control Group 2. 
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 1-A 
               
             
             
               
                   
               
               
                 Comparisons of Experimental Group 1 with Control Group 1 and Control 
               
               
                 Group 2. 
               
             
          
           
               
                   
                 Magnet 
                 Difference 
                 Total 
                 Difference in 
                 Total Magnetic 
                 Difference in 
               
               
                   
                 Volume 
                 in Volume 
                 Thickness 
                 thickness 
                 Flux Density 
                 Magnetic 
               
               
                   
                 (mm 3 ) 
                 (%) 
                 (mm) 
                 (%) 
                 (mT) 
                 Flux (%) 
               
               
                   
                   
               
             
          
           
               
                 Control 
                 373 
                 −10.7 
                 10.4 
                 −4.8 
                 695.56 
                 9.2 
               
               
                 Group 1 
               
               
                 Control 
                 333 
                 0 
                 10.08 
                 −1.8 
                 688.96 
                 10.2 
               
               
                 Group 2 
               
               
                 Experimental 
                 333 
                 — 
                 9.9 
                 — 
                 759.52 
               
               
                 Group 1 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 1-B 
               
             
             
               
                   
               
               
                 Comparisons of Experimental Group 1 with 
               
               
                 Control Group 1 and Control Group 2. 
               
             
          
           
               
                   
                 Weighted 
                   
                   
                   
                   
               
               
                   
                 Axial 
                 Difference 
                   
                   
                 Difference 
               
               
                   
                 Magnetic 
                 in Weighted 
                   
                   
                 in 
               
               
                   
                 Flux 
                 Axial 
                   
                 Difference 
                 torque 
               
               
                   
                 Density 
                 Magnetic 
                 Torque 
                 in torque 
                 density 
               
               
                   
                 (mT) 
                 Flux (%) 
                 (mN-m) 
                 (%) 
                 (%) 
               
               
                   
                   
               
             
          
           
               
                 Control 
                 642.73 
                 9.52 
                 43.46 
                 −0.65 
                 4.37 
               
               
                 Group 1 
               
               
                 Control 
                 619.96 
                 13.5 
                 38.28 
                 12.8 
                 14.84 
               
               
                 Group 2 
               
               
                 Experimental 
                 703.94 
                 — 
                 43.17 
                 — 
                 — 
               
               
                 Group 1 
               
               
                   
               
             
          
         
       
     
         [0053]    According to the simulation analysis shown above, comparing Experimental Group 1 with Control Group 1, Experimental Group 1 has a lower magnet volume and total thickness under the condition of having the same torque, so the material cost may be reduced. Moreover, the total magnetic flux density, weighted axial magnetic flux density, and torque density of Experimental Group 1 are much higher. 
         [0054]    Comparing Experimental Group 1 with Control Group 2, Experimental Group 1 has a thinner thickness under the condition of having the same magnet volume. Moreover, the total magnetic flux density, weighted axial magnetic flux density, torque, and torque density of Experimental Group 1 are much higher. 
         [0055]    The experimental group and control group below are compared under the condition of having the same rotor&#39;s volume and with different gaps. The torque is compared between the experimental group, which has the convex and concave parts, and the control group, which does not have the convex and concave parts. The gaps for the experimental group are the gaps between the convex parts  212  and the concave parts  311  in the embodiments. The gaps for the control group are the gaps between the rotor and the stator. Moreover, the experimental group 1 is the single gap axial permanent magnet motor described above. The experimental group 2 is the mover and stator assembly of electric machine  1  shown in the embodiments from  FIG. 1  to  FIG. 5A  with rated power being 1500 W, 3 phase alternate current voltage, external diameter of the rotation shaft being 86 mm, and external diameter of the rotor being 170 mm. The experimental group 3 is the mover and stator assembly of electric machine  1  shown in  FIGS. 13 to 16A  applied for the simulation of a single gap radial motor with rated power being 7500 W, 3 phase alternate current voltage, thickness of the mover and stator assembly of electric machine being 150 mm, external diameter of the rotation shaft  32  being 48 mm, and external diameter of the rotor being 210 mm. 
         [0000]    
       
         
               
             
               
               
             
               
               
               
               
             
               
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
             
             
               
                   
               
               
                 Torque comparison of experimental group and control group 
               
             
          
           
               
                   
                 Torque (N-M) 
               
             
          
           
               
                   
                   
                 Simulation 2 
                   
               
               
                   
                 Simulation 1 
                 1,500 W 
                 Simulation 3 
               
               
                   
                 80 W single gap 
                 double gaps 
                 7,500 W 
               
               
                   
                 Axial permanent 
                 Axial permanent 
                 single gap 
               
               
                   
                 magnet motor 
                 magnet motor 
                 Radial motor 
               
             
          
           
               
                   
                 Gap (mm) 
               
             
          
           
               
                   
                 1 
                 0.6 
                 1 
                 0.8 
                 1 
                 0.8 
               
               
                   
                   
               
             
          
           
               
                 Experimental 
                 0.04317 
                 0.05192 
                 9.80 
                 12.08 
                 31.18 
                 33.01 
               
               
                 Group 
               
               
                 Control 
                 0.03828 
                 0.04572 
                 7.68 
                 8.88 
                 29.71 
                 29.92 
               
               
                 Group 
               
               
                 Difference (%) 
                 12.8 
                 13.6 
                 27.6 
                 36.0 
                 4.9 
                 10.3 
               
               
                   
               
             
          
         
       
     
         [0056]    From the simulation results above, the torque of each experimental group is all higher than the torque of its corresponding control group. Thus, the mover and stator assembly of electric machine may direct and gather the magnetic circuit to reduce the side magnetic loss during the rotation of the rotor. The magnetic flux density is then increased to enhance the efficiency of the first magnetic part and the second magnetic part, so the total efficiency may be enhanced. Moreover, the gap distance and the torque in the simulations of the mover and stator assembly of electric machine above are inversely proportional to each other. 
         [0057]    The rotor and stator structure with convex and concave parts described above may apply to linear movement structure. Please refer to  FIG. 18 , which is a perspective view diagram of an example mover and stator assembly of electric machine in an embodiment. The mover and stator assembly of electric machine  1 ′ of the embodiment is a linear movement structure and comprises a stator  2 ′ and a moving part  3 ′. The stator  2 ′ comprises a first magnetic part  20 , which further comprises a first surface  211  and two convex parts  212  protruding from the first surface  211 . The moving part  3 ′ comprises a second magnetic part  31 , which further comprises a second surface  312  and two concave parts  311  set up at the second surface  312 . The first surface  211  faces the second surface  312 . The width of the convex parts  212  is smaller than the width of the concave parts  311 . The convex parts  212  and the concave parts  311  are set up along the moving direction of the moving part  3 ′. When in motion, the concave parts  311  move linearly along the convex parts  212 . The number of convex parts and concave parts are not to have any limitations on this disclosure. In other embodiments, the number of convex parts  212  and concave parts  311  may be one, two, or greater than two. The set up of the convex parts  212  and convex parts  311  above may prevent side magnetic loss and increase the magnetic flux density between the stator  2 ′ and the moving part  3 ′, thereby increasing the output torque. 
         [0058]    In this embodiment, the second magnetic part  31  is a permanent magnet or a magnetic conductive part. The magnetic conductive part is a silicon-steel sheet. Or the material of the magnetic conductive part is soft magnetic composite (SMC) material. 
         [0059]    However, in other embodiments, the stator  2 ′ of the mover and stator assembly of electric machine  1 ′ may not have convex part and the moving part  3 ′ may not have concave part. The first magnetic part  20  of the stator  2 ′ may comprise a concave part set up at the first surface (not shown in FIG). The second magnetic part  31  of the moving part  3 ′ may comprise a convex part set up at the second surface (not shown in FIG). The convex part and the concave part face each other. The convex part moves linearly along the concave part to achieve the effect of increase in power in the disclosure. 
         [0060]    In this disclosure, the cross-sectional shape of the convex part  212  of the mover and stator assembly of electric machine  1 ′ may be rectangle, circular arc, semicircle, cylinder, isosceles triangle with chamfered top surface, isosceles triangle, right triangle, isosceles trapezoid, right trapezoid, or right trapezoid with chamfered top surface. The cross-sectional shape of the concave part  311  of the mover and stator assembly of electric machine  1 ′ may be rectangle, circular arc, semicircle, cylinder, isosceles triangle with chamfered top surface, isosceles triangle, right triangle, isosceles trapezoid, right trapezoid, or right trapezoid with chamfered top surface. 
         [0061]    Please refer to  FIG. 19A , which is a perspective diagram of an example mover and stator assembly of electric machine in an embodiment. This embodiment is similar to the embodiment in  FIG. 18 . In this embodiment, the two convex parts  212  each respectively have three convex sections  212   d ,  212   e , and  212   f . The three convex sections  212   d ,  212   e , and  212   f  are set up separately along the moving direction of the moving part  3 ′. There is a concave section,  2124  and  2125 , between each of the three convex sections  212   d ,  212   e , and  212   f . The concave sections  2124  and  2125  each respectively have a first wall  2124   a ,  2125   a  and a second wall  2124   b ,  2125   b . The first walls  2124   a  and  2125   a  face the same direction and the second walls  2124   b  and  2125   b  also face another same direction. In this embodiment, the distance between the first walls  2124   a  and  2125   a  equals to the distance between the second walls  2124   b  and  2125   b . In other words, the concave sections have the same width, so the convex sections  212   d ,  212   e , and  212   f  have the same gap distance between each other, thereby increasing the output torque of the mover and stator assembly of electric machine. 
         [0062]    Furthermore, when the stator  2 ′ comprises concave part and the moving part  3 ′ comprises convex part (not shown in FIG), the convex parts of the moving part  3 ′ may comprise several convex sections and concave sections between the convex sections. The convex sections are set up separately with same gap distance in between. 
         [0063]    Please refer to  FIG. 19B , which is a perspective diagram of an example mover and stator assembly of electric machine in an embodiment. In this embodiment, the convex part  212  has three convex sections  212   d ,  212   e , and  212   f  set up separately along the moving direction of the moving part  3 ′. There is a concave section,  2124  and  2125 , between each of the three convex sections  212   d ,  212   e , and  212   f . The concave sections  2124  and  2125  each respectively have a first wall  2124   a ,  2125   a  and a second wall  2124   b ,  2125   b . The distance between the first walls  2124   a  and  2125   a  is different from the distance between the second walls  2124   b  and  2125   b . In other words, the concave sections  2124 ,  2125  have different width and the convex sections  212   d ,  212   e , and  212   f  have different gap distance between each other, thereby increasing the output torque of the mover and stator assembly of electric machine. 
         [0064]    Furthermore, when the stator  2 ′ comprises concave part and the moving part  3 ′ comprises convex part (not shown in FIG), the convex parts of the moving part  3 ′ may comprise several convex sections and concave sections between the convex sections. The convex sections are set up separately with different gap distance in between because of the different widths of the concave sections. 
         [0065]    The magnetic conductive part in the disclosure may be soft magnetic composite (SMC) or resin-bonded magnet. Soft magnetic composite (SMC) is primarily made of iron, iron based powder, and different proportions of silicon, aluminum, manganese mixed together with binder. Binder is generally inorganic material such as mixture of phosphorus and silicon dioxide. Therefore, since the soft magnetic composite (SMC) is nonconductive, it is more capable of controlling the eddy current than the silicon-steel sheet in the prior art. 
         [0066]    Furthermore, resin-bonded magnet is primarily made of neodymium, iron, and boron. Since resin-bonded magnet does not consist of dysprosium, the cost for materials may then be reduced. Also, with oxidation treatment on the surface of the magnetic conductive part, the lifespan of the magnetic conductive part may be increased. 
         [0067]    According to the mover and stator assembly of electric machine in the disclosure, the structure of the corresponding convex and concave parts may direct and gather the magnetic flux to reduce the side magnetic loss during the rotation of the rotor. The magnetic flux density may then be increased to enhance the efficiency of the first magnetic part and the second magnetic part. Thus, the output torque may be increased to enhance the overall energy efficiency. Moreover, the mover and stator assembly of electric machine may use less materials than the assemblies in prior art to generate higher output torque and reduce the manufacturing cost.