Rotating electric machine, in particular for the starter of an automotive vehicle

Abstract

A DC electric rotating machine mainly for the starter of an automotive vehicle, including: a stator having a magnetised structure with permanent magnetisation and extending along the circumference of the stator; a rotor; a set of brushes adapted for the electric supply of the rotor by switching the electrical current in sections of the rotor; wherein the magnetised structure ( 5 ) of the stator includes at least one sector, between two consecutive magnetic poles (N; S) of the magnetised structure, having a magnetisation vector that varies in an essentially sinusoidal manner upon displacement on the stator circumference, and wherein the angular deviation of the neutral line is selected so as to improve the switching during the operation of the machine.

1 : A direct current rotating electrical machine for an automotive vehicle starter ( 1 ), the machine including:
 a stator ( 3 ) including a magnetised structure with permanent magnetisation, extending around a circumference of the stator,   a rotor ( 2 ),   a group of brushes ( 13 ,  14 ) adapted to supply electrical power to the rotor by switching the electrical current in sections of the rotor,   wherein the magnetized structure ( 5 ) of the stator includes at least one sector, between two consecutive magnetic poles (N; S) of that structure, having a magnetization vector varying substantially sinusoidally around the circumference of the stator ( 3 ), and wherein the angular offset of the neutral line is chosen to improve switching when the machine is operating.   
     
     
         2 : The machine according to  claim 1 , wherein the angular offset of the neutral line is greater than 15 electrical degrees. 
     
     
         3 : The machine according to  claim 1 , wherein the magnetization vector within the magnetized structure varies substantially sinusoidally over the whole of the circumference of that structure. 
     
     
         4 : The machine according to  claim 1 , wherein the magnetized structure comprises at least one sector having a magnetization vector varying non-sinusoidally with a radial direction in the sector, this sector notably subtending an electrical angle greater than 10°. 
     
     
         5 : The machine according to  claim 1 , forming an automotive vehicle starter, further comprising a strong armature reaction. 
     
     
         6 : The machine according to  claim 1 , further comprising a speed reducer. 
     
     
         7 : The machine according to  claim 1 , further comprising six or more poles. 
     
     
         8 : The machine according to  claim 1 , wherein the magnetized structure includes at least one permanent magnet based on NdFeB. 
     
     
         9 - 44 . (canceled)