Patent ID: 6700287
Filing Date: 2004-03-02
Classification: H02K

Abstract:
A core of a motor comprising:a plurality of core sheets, which are of one type and are stacked together, each core sheet including: an inner annular portion, an outer annular portion; and a plurality of stays that are arranged at equal angular intervals in a circumferential direction of the core sheet and connect the inner annular portion to the outer annular portion, so that each adjacent two stays of the core sheet define a window opening therebetween, wherein: the inner annular portion has a rotatable shaft securing hole chat extends through a center of the inner annular portion in an axial direction of the core to receive a rotatable shaft of the motor, and the outer annular portion includes a plurality of teeth that are arranged at equal angular intervals in the circumferential direction of the core sheet and extend radially outward from the outer annular portion, wherein each adjacent two teeth of the core sheet define a slot therebetween; each core sheet further includes at least one projection, at least one recess and a receiving portion, which are all arranged along a concentric circle that is concentric to a rotational axis of the rotatable shaft of the motor, wherein the at least one projection is arranged in a first axial end surface of the core sheet, and the at least one recess and the receiving portion are arranged in a second axial end surface of the core sheet in such a manner that each one of the at least one projection of the core sheet is opposed to a corresponding one of the at least one recess of the core sheet in the axial direction of the core, and the receiving portion is displaced from the at least one projection of the core sheet in the axial direction of the core; at least two adjacent core sheets of the core sheets are displaced one after the other by a predetermined displacement angle in a circumferential direction of the core in such a manner that the stays of one of the at least two adjacent core sheets are partially overlapped with the stays of the other one of the at least two adjacent core sheets, respectively, and the slots of the one of the at least two adjacent core sheets are aligned with the slots of the other one of the at least two adjacent core sheets in the axial direction of the core, respectively, and the second axial end surface of the one of the at least two adjacent core sheets is opposed to the first axial end surface of the other one of the at least two adjacent core sheets, and each one of the at least one projection arranged in the first axial end surface of the other one of the at least two adjacent core sheets is substantially, entirely received in a corresponding one of the receiving portion and the at least one recess arranged in the second axial end surface of the one of the at least two adjacent core sheets, so that the first axial end surface of the other one of the at least two adjacent core sheets closely contacts the second axial end surface of the one of the at least two adjacent core sheets.