An axial field electric machine having an improved efficiency includes a number of magnetic elements (e.g., as a rotor) as annular disks magnetized to provide multiple sector-shaped poles. Each sector has a polarity opposite that of an adjacent sector, and each sector is polarized through the thickness of the disk. The poles of each disk are aligned with opposite poles of each adjacent magnet. Metal members adjacent the outermost disks contain the flux. The axial field electric machine also includes one or more conductor elements (e.g., as a stator) which include a number of conductor phases that traverse the flux emanating between poles of axially adjacent magnetic elements. The design of the axial field electric machine including the gap spacing between adjacent magnetic elements, the transition width between adjacent poles on each magnetic element, the number of poles, the number and width or conductor phases in the conductor element is based on the physical characteristics of the magnetic elements to increase efficiency.
RELATED APPLICATIONS
The present application is a continuation-in-part of U.S. application Ser. No. 08/763,824, filed Dec. 11, 1996, the disclosure of which is hereby incorporated by reference in its entirety.
A motor having a rotor with a plurality of magnetic poles arranged in an arch or circular shape and a stator in which coils are disposed on the magnetic teeth of a stator core having a plurality of the magnetic teeth disposed opposite to the rotor, wherein a magnetic pole part for cancelling a cogging torque is disposed around the rotor.
An electrical machine includes first and second magnetically permeable parallel cores. Each core is elongated to thereby define a lengthwise direction and first and second core profiles transverse to the lengthwise direction. First coils are wound about the first core profile and sequentially disposed along the length of the first core. Second coils are wound about the second core profile and sequentially disposed along the length of the second core. A multi-pole elongated permanent magnet is parallel with the cores and located between them. The magnet is movable, relative to the cores, in the lengthwise direction.
An outer rotor type brushless direct current motor has an outer rotor including a plurality of permanent magnets attached along the inner circumference of an annular yoke such that the magnetic poles face the S magnetic poles. Thin sections are formed by chamfering the radially outer periphery of the two end sections in the circumferential direction of each of the permanent magnets. Magnetic flux passage sections of the yoke providing connection between the thin sections of adjacent permanent magnets are expanded radially inwards. In accordance with the above-mentioned arrangement, the cross section of the magnetic path in the magnetic flux passage sections is increased, thereby suppressing the occurrence of magnetic saturation and preventing the maximum torque of the permanent magnets from decreasing while reducing their size. Moreover, because the magnetic flux passage sections of the yoke are expanded radially inwards, the external dimensions of the yoke do not increase.
An electrical machine having a magnet assembly with a magnet carrier ring with an even number of permanent magnets mounted in the carrier ring around a circular locus, and a conductor assembly with one or more conductor circuits wound in a double helix wave winding around a flat conductor support ring with the conductor circuits having uniformly curved conductor segments of involute or arcuate configuration wherein the magnet assembly and conductor assembly are contained in a housing with the magnet assembly rotating relative to the conductor assembly.
