Abstract: A pole for use in a magnetic circuit includes a flux-passing portion for passing magnetic flux and a cap. The flux-passing portion has a face through which at least some of the magnetic flux passes and to which the cap is fixed. The cap is made of a permeable material and is formed to impede eddy currents in the cap. The cap may have a top and bottom surface joined by a shoulder to provide a distribution of magnetic flux through the shoulder that is less concentrated than the flux distribution through a 90-degree corner. The pole may be incorporated into a generator, a motor, a linear motor, or a portable engine-driven generator to increase the efficiency thereof.

Abstract: A method of producing the core of an electric motor by providing a stack of laminations of magnetic material. Windows are formed in the laminations for one or more magnetic elements to be placed in each window. Each window has an end edge portion (17) which is to be at the peripheral edge (18) of the lamination of the finished version of the rotor. The laminations originally have an annular radial extension (60-61) and after the core is assembled with end caps, the annular radial extension (60-61) is removed so that the window end edge portions (17) are at the periphery (18) of the laminations. There is a polar peripheral portion (20) between each window and the periphery (18) of the lamination and an intermediate peripheral portion (40) between two adjacent polar peripheral portions, with such intermediate polar portions having reduced electrical conductibility and reduced magnetic permeability.

Abstract: Difficulties in self-starting a permanent magnet motor are eliminated in a structure including a stator with a rotor journalled within the stator for rotation about an axis. The rotor includes a body of ferromagnetic material having a nominally cylindrical peripheral surface concentric with the axis. Permanent magnets are located on the peripheral surface to define equally angularly spaced magnetic poles with alternating ones of the poles being of opposite polarity. A thin, hollow cylinder formed of a good electrically conducting material is disposed on the body to sandwich the magnets against the peripheral surface of the body and provides a situs for the generation of localized induced electrical current which generates magnetic fields that react with rotating magnetic fields in the stator to start the motor from a dead stop without the need for position sensors or controlled electronics.

Abstract: In an ultra-permanent-magnet-type electric rotating machine including a stator in which a winding of armatures is wound in each of a plurality of slots of a stator core, and a rotor having permanent magnets respectively inserted into permanent-magnet-inserting holes in a magnetic steel sheet ring provided at an outer periphery of a conductive and magnetic shaft, the thickness of the stator core is 0.1 to 0.2 mm, and the magnetic steel sheet ring is made of a high-tensile-strength magnetic steel sheet had tensile strength of 80 kg/mm2 or more.