Ex parte MIYAZAWA et al. - Page 2

          Appeal No. 1997-3279                                       Page 2           
          Application No. 08/240,702                                                  

          motor suffers several disadvantages.  Specifically, the                     
          excitation torque generated at the stable point position of                 
          the motor's permanent                                                       
          magnet rotor is small.  Because a magnetic balance has to be                
          destroyed to start the motor, moreover, the magnetic pole                   
          shape thereof becomes special, and flux leakage is increased,               
          which reduces the motor's efficiency.  In addition, the                     
          different magnetic pole shapes of the motor's stator yokes                  
          complicate assembly.                                                        

               The inventive brushless DC motor includes a rotor having               
          magnetic poles, a stator having magnetic poles, and a field                 
          coil.  The ratio of the open angle of the stator's magnetic                 
          poles to the open angle of the rotor's magnetic poles is                    
          between 0.75 and 1.  Such a ratio ensures that the stable                   
          point position of the rotor is in vicinity of a maximum point               
          of torque generated by the field coil, which provides a high                
          starting torque.  The stator's magnetic poles are alternately               
          disposed at regular intervals in the circumferential direction              
          with a constant air gap from the rotor magnet.  The constant                
          air gap limits flux leakage into the gap, which increases the               

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