Method of manufacturing permanent-magnet synchronous motor

Abstract

In a combination of, for example, a rotor having eight magnetic poles and a stator having twelve slots and pulsating components of permeance, which generate a sinusoidal cogging torque having maxima of the same number as the number of poles of the rotor, pressurizing parts arranged in predetermined positions, applying a force at an outer periphery of the stator and directed inwardly cancels the pulsating components of the cogging torque.

1 - 9 . (canceled) 
     
     
         10 . A method of manufacturing a permanent-magnet synchronous motor comprising:
 inserting and assembling a rotor having permanent magnets with 2×p poles (P is a natural number) into a torus of a stator core that has a torus shape and has Z (Z is a natural number) slots, on which a coil is arranged;   rotating the rotor in a state in which electric current is not flowing through the coil, to measure cogging torque for every angle;   determining those locations, in which an outer periphery of the stator core is pressurized, based on measurements of the cogging torque; and   assembling pressurizing parts, which pressurize the outer periphery of the stator core outwardly of the stator core at N locations, N being any of positive values calculated from N=p, N=±2×p−Z×il (il is an integer of at least 0), and N=Z(il±2)p.   
     
     
         11 . A method of manufacturing a permanent-magnet synchronous motor by fixing a stator core in a frame, the method comprising positioning the frame and a stator core in an arrangement ;  in which stress applied to the stator core from the frame has a maximum in a predetermined region of the stator core, to fix the stator core to the frame. 
     
     
         12 . The method of manufacturing a permanent-magnet synchronous motor according to  claim 11 , wherein the frame has a substantially circular shape, including an elliptical shape, and including positioning the stator core so that one of a tooth center line and a slot center line of the stator core is consistent with one of a minor axis and a major axis of the frame, and fixing the stator core to the frame. 
     
     
         13 . The method of manufacturing a permanent-magnet synchronous motor according to  claim 11 , including positioning the frame and the stator core so that stress applied to the stator core from the frame becomes a maximum, and becomes consistent with one of a tooth center line and a slot center line of the stator core, and fixing the stator core to the frame. 
     
     
         14 . The method of manufacturing a permanent-magnet synchronous motor according to  claim 11 , wherein the frame is a square frame, and including positioning the frame so that one of a tooth center line and a slot center line of the stator core is consistent with a diagonal line of the frame, and fixing the stator core to the frame. 
     
     
         15 . The method of manufacturing a permanent-magnet synchronous motor according to  claim 11 , wherein positioning between the frame and the stator core is made every type of the motor so that an arrangement, in which stress applied on the stator core from the frame becomes minimum or maximum in a thickness distribution in a normal direction of the frame, and becomes minimum in rate of change of the thickness, becomes consistent with a teeth center line or a slot center line of the stator core, and the stator core is fixed to the frame. 
     
     
         16 . The method of manufacturing a permanent-magnet synchronous motor according to  claim 11 , wherein when positioning is made every type of the motor so that an arrangement, in which stress applied on the stator core from the frame becomes minimum or maximum, becomes consistent with a teeth center line or a slot center line of the stator core, positioning between the frame and the stator core is made in an angular region in a range of positioning accuracy in view of manufacture, and the stator core is fixed to the frame. 
     
     
         17 . The method of manufacturing a permanent-magnet synchronous motor according to  claim 11 , wherein an articulation type stator core, which needs butt portions or welds, or a thin-wall connection type stator core is adopted, positioning between the frame and the stator core is made so that an arrangement, in which a thickness distribution in a normal direction of the frame becomes minimum and the thickness becomes minimum in rate of change, becomes consistent with the butt portions or welds, and the stator core is fixed to the frame. 
     
     
         18 . The method of manufacturing a permanent-magnet synchronous motor according to  claim 16 , wherein a range of accuracy at the time of positioning is in an angular region of ±10 degrees. 
     
     
         19 . The method of manufacturing a permanent-magnet synchronous motor according to  claim 17 , wherein a range of accuracy at the time of positioning is in an angular region of ±10 degrees.