Patent Publication Number: US-2018048195-A1

Title: Electric motor

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an electric motor, and more particularly to a micro power generating structure. The electric motor is light in weight. When the electric current is outputted, it doesn&#39;t need rectification. The magnetic flux is enhanced effectively. 
     2. Description of the Prior Art 
     A conventional power generator  1 , as shown in  FIG. 1 ,  FIG. 2  and  FIG. 10 , includes a permanent magnet rotor  11 . The permanent magnet rotator  11  is composed of a North pole  111  and a South pole  112 . Two corresponding sides of the permanent magnet rotor  11  are provided coils  12 . A magnetic yoke  13  is provided to wrap the exteriors of the coils  12 . When running, the permanent magnet rotator  11  is rotated, enabling the magnetic field lines from the North pole  111  and the South pole  112  to pass through the coils  12 . As shown in  FIG. 1 , when the permanent magnet rotator  11  is turned 0 or 360 degrees, the power generator generates forward current. As shown in  FIG. 2 , when the permanent magnet rotator  11  is turned 180 degrees, the power generator generates reverse current. When the permanent magnet rotator  11  is turned 90 or 270 degrees, there is no electric current generation because the magnetic field lines don&#39;t pass through the coils  12 . The conventional power generator uses silicone steel sheets, so it is heavy in weight and large in size. The electric current includes forward current and reverse current. When the electric current is outputted, it must be rectified by a rectifier to output direct current. Besides, only one magnetic yoke is used to wrap the whole exterior of the power generator, the magnetic field lines are diffused. Specially, the magnetic field strides the central spindle  10 . When running, the magnetic field lines are diffused easily, which lowers the magnetic flux. The efficiency is also lowered accordingly. The number of the magnetic poles of the conventional power generating structure must be even for running. 
     Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve these problems. 
     SUMMARY OF THE INVENTION 
     The primary object of the present invention is to provide an electric motor to improve the shortcomings of the prior art. The electric motor doesn&#39;t use silicon steel plates, so it is light in weight. 
     Another object of the present invention is to provide an electric motor which directly generates forward current all the time because the directions of the magnetic field lines are the same, from the outside toward the central spindle, and the magnetic field lines don&#39;t pass through the spindle. When the electric current is outputted, it doesn&#39;t need rectification. 
     A further object of the present invention is to provide an electric motor which generates independent magnetic fields, so the magnetic flux per unit area is two times as much as the prior art according to the inventor&#39;s experiment. Compared to the prior art, the magnetic field lines generated by the present invention won&#39;t be diffused around and interfere with each other. 
     In order to achieve the aforesaid object, the electric motor of the present invention may include a main body. The main body includes a permanent magnet rotor unit and a stator unit. The electric motor may further include two bearings, two bearing seats, and a casing. 
     Preferably, the permanent magnet rotor unit includes a spindle at a central portion thereof. A portion of the spindle is fixedly connected with a connecting member. At least one side of the connecting member is fixedly connected with a magnet. An outer side of the magnet is connected with a magnetic yoke. The cross-section of the magnetic yoke is in a U-like shape. A space is defined between the magnet and the magnetic yoke. 
     Preferably, the stator unit includes a plate body. The plate body has a central opening. The opening is adapted for insertion of the spindle. The plate body is provided with a cylindrical extension body. The inside of the extension body is a hollow compartment. At least one coil is embedded on the extension body. The plate body is provided with at least one protruding block. The extension body with the coil is mounted to the space between the magnet and the magnetic yoke. 
     Preferably, the two bearings are fitted on two ends of the spindle. 
     Preferably, the central portions of the two bearing seats are configured to receive the two bearings. The two bearing seats are disposed at the exterior of the permanent magnet rotor unit and the stator unit. 
     Preferably, the casing is hollow and has two open ends to accommodate the permanent magnet rotor unit and the stator unit therein. An inner wall of the casing is formed with at least one groove. The groove is adapted for engagement of the protruding block of the stator unit. The two bearing seats are locked with screws to seal the casing. 
     Preferably, the magnet has an outer curved surface. The magnetic yoke located at the outer end of the magnet also has an arc shape corresponding to the magnet. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view of a conventional power generator; 
         FIG. 2  is another schematic view of the conventional power generator; 
         FIG. 3  is a perspective view of the present invention; 
         FIG. 4  is an exploded view of the present invention; 
         FIG. 5  is a side sectional view of the present invention; 
         FIG. 6  is a top sectional view of the present invention; 
         FIG. 7  is a schematic view showing rotation of the permanent magnet rotor unit of the present invention; 
         FIG. 8  is another schematic view showing rotation of the permanent magnet rotor unit of the present invention; 
         FIG. 9  is a further schematic view showing rotation of the permanent magnet rotor unit of the present invention; 
         FIG. 10  is a schematic view showing the magnetic field of the conventional power generator; and 
         FIG. 11  is a schematic view showing the magnetic field of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings. 
     Referring to  FIG. 3 ,  FIG. 4 ,  FIG. 5  and  FIG. 6 , the present invention discloses an electric motor which is light in weight and doesn&#39;t need rectification. The electric motor includes a main body  2 . The main body  2  includes a permanent magnet rotor unit  21  and a stator unit  22 . The electric motor further includes two bearings  23 , two bearing seats  24 , and a casing  25 . The permanent magnet rotor unit  21  includes a spindle  211  at a central portion thereof. A portion of the spindle  211  is fixedly connected with a connecting member  212 . At least one side of the connecting member  212  is fixedly connected with a magnet  213 . An outer side of the magnet  213  is connected with a magnetic yoke  214 . The cross-section of the magnetic yoke  214  is in a U-like shape. A space  215  is defined between the magnet  213  and the magnetic yoke  214 . The stator unit  22  includes a plate body  221 . The plate body  221  has a central opening  220 . The opening  220  is adapted for insertion of the spindle  211 . The plate body  221  is provided with a cylindrical extension body  222 . The inside of the extension body  222  is a hollow compartment  224 . At least one coil  223  is embedded on the extension body  222 . The plate body  221  is provided with at least one protruding block  225 . The extension body  222  with the coil  223  is mounted to the space  215  between the magnet  213  and the magnetic yoke  214 . The two bearings  23  are fitted on two ends of the spindle  211 . The central portions of the two bearing seats  24  are configured to receive the two bearings  23 . The two bearing seats  24  are disposed at the exterior of the permanent magnet rotor unit  21  and the stator unit  22 . The casing  25  is hollow and has two open ends to accommodate the permanent magnet rotor unit  21  and the stator unit  22  therein. An inner wall of the casing  25  is formed with at least one groove  251 . The groove  251  is adapted for engagement of the protruding block  225  of the stator unit  22 . The two bearing seats  24  are locked with screws  26  to seal the casing  25 . The magnet  213  has an outer curved surface. The magnetic yoke  214  located at the outer end of the magnet  213  also has an arc shape corresponding to the magnet  213 . 
     The stator unit  22  of the present invention is fixedly connected with the casing  25  and the bearing seats  24 . The permanent magnet rotor unit  21  is rotated relative to the stator unit  22  by means of the bearings  23 . 
     Referring to  FIG. 7 , when the spindle  211  is rotated by an external force, the permanent magnet rotor unit  21  is rotated relative to the stator unit  22 . When the rotation angle is defined as 0 or 360 degrees as shown in the drawing, the magnetic yoke  214 , the coil  223 , and the magnet  213  form magnetic field lines to pass through the coil  223 . The direction of the generated electric current is from the magnetic yoke  214  through the coil  223  toward the central magnet  213 . The magnetic field lines at two sides of the spindle  211  don&#39;t pass through the central spindle  211 . Referring to  FIG. 8 , when the spindle  211  is rotated to bring the permanent magnet rotor unit  21  to rotate relative to the stator unit  22  and the rotation angle is defined as 90 or 270 degrees as shown in the drawing, because the magnetic field lines don&#39;t pass through the coil  223 , there is no electric current generation. Referring to  FIG. 9 , when the spindle  211  is rotated to bring the permanent magnet rotor unit  21  to rotate relative to the stator unit  22  and the rotation angle is defined as 180 degrees as shown in the drawing, the magnetic yoke  214 , the coil  223 , and the magnet  213  form magnetic field lines to pass through the coil  223 . The direction of the generated electric current is from the magnetic yoke  214  through the coil  223  toward the central magnet  213 . No matter what angle the permanent magnet rotor unit  21  of the present invention is turned, the direction of the generated electric current is from the magnetic yoke  214  through the coil  223  toward the central magnet  213  all the time. That is to say, all the electric current is forward current, which can be output directly, without rectification. Furthermore, the directions of the magnetic field lines are the same, not passing through the central spindle  211 . Each magnetic field is independent, not interfering with each other, so the magnetic field lines won&#39;t be diffused and interfere with each other to enhance the magnetic flux effectively. 
     Referring to  FIG. 10  and  FIG. 11 , the difference between the prior art and the present invention can be seen clearly. As shown in  FIG. 10 , the electric current includes forward current and reverse current. When outputted, the electric current must be rectified by a rectifier to output direct current. In addition, only a magnetic yoke is used to wrap the whole exterior of the power generator. The magnetic field lines are diffused, and the magnetic field goes across the central spindle  10 . During running, the magnetic field lines are easily diffused around, so the whole magnetic flux is lowered. The efficiency is also lowered. On the contrary, as shown in  FIG. 11 , each magnetic field of the present invention is independent and disposed at the periphery of the spindle  211 , namely the center of the magnetic field and the spindle are not coaxial. All the magnetic field lines face the spindle  211  in the same direction, without diffusion. 
     Accordingly, the electric motor of the present invention is light in weight and doesn&#39;t need rectification. The weight is decreased, and the size is reduced, and the magnetic flux is increased, and there is no need for rectification when the electric current is outputted. The advantages of the present invention are numerous. 
     Although particular embodiments of the present invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the present invention. Accordingly, the present invention is not to be limited except as by the appended claims.