Patent ID: 7777391
Filing Date: 2010-08-17
Classification: H02K,Y10T

Abstract:
1. An armature comprising: a magnetic material plate having a plurality of first magnetic members arranged circularly; a plurality of magnetic cores; and coils, wherein in each one of said first magnetic members, one of said magnetic cores projecting toward the opposite side to one direction on a surface of said one of said first magnetic members, which has a surface on the opposite side to one of said magnetic cores on which said one of said first magnetic materials is arranged, whose area is larger than the area of a cross section of said one of said magnetic cores on the side of said one of said first magnetic members, and has a cavity with another one of said first magnetic members, the outline of each of said cavities between said first magnetic members adjacent to each other in a circular direction extends from an inner circumference side to an outer circumference side of said magnetic material plate, and said coils are arranged around said magnetic cores along said surface, said armature further comprising said plate is a second magnetic material plate having a plurality of second magnetic members arranged circularly, each one of said second magnetic members has a cavity with another one of said second magnetic members, the outline of said cavity between said second magnetic members adjacent to each other in a circular direction extends from an inner circumference side to an outer circumference side of said second magnetic material plate, the area of a surface on the opposite side to one of said magnetic cores covered by said one of said second magnetic members is larger than the area of a surface of said one of said magnetic cores on the side of said one of said second magnetic members.