Abstract: A DC brushless motor 3 is provided which comprises armature 31 and rotor 32. Rotor 32 is provided with a rotor yoke that has four main poles 321 on its periphery. Slots with a radial-direction size of L.sub.m are formed on main poles 321 of the rotor yoke. Magnetic-field permanent magnet 323 with an approximate thickness of L.sub.m is embedded in each slot 322, such that the radial-direction size L.sub.m of slot 322 and the air gap length L.sub.g of the air gap formed between rotor 32 and armature 31 satisfy the relationship 0<L.sub.m +L.sub.g .ltoreq.2 mm.

Abstract: In an alternating current generator and fans thereof in accordance with the invention, the cooling efficiency of the alternating current is improved by fans fixed to a rotor. When the fans are formed during a press working operation, the blades are formed directly from the fans by cut-raising the fans toward a bracket side to form blades and simultaneously cut-raising protruding portions toward a rotor side to form protrusions. This design allows for both improvement in cooling efficiency of the alternating current generator and ease of manufacture of the fans.

Abstract: The present invention is an energy storage apparatus. The energy storage apparatus includes a rotor, a stator and a hub rotatably positioned about an axial shaft. The hub includes at least one spoke plane projecting radially from the hub, and the at least one spoke plane includes at least one spoke. The at least one spoke becomes progressively thinner along an increasing radius.

Abstract: A DC brushless motor 3 is provided which comprises armature 31 and rotor 32. Rotor 32 is provided with a rotor yoke that has four main poles 321 on its periphery. Slots with a radial-direction size of L.sub.m are formed on main poles 321 of the rotor yoke. Magnetic-field permanent magnet 323 with an approximate thickness of L.sub.m is embedded in each slot 322, such that the radial-direction size L.sub.m of slot 322 and the air gap length L.sub.g of the air gap formed between rotor 32 and armature 31 satisfy the relationship 0<L.sub.m +L.sub.g .ltoreq.2 mm.

Abstract: Disclosed is an engine-driven welding generator using a plurality of neodymium-iron-boron based rare earth magnets and provided with countermeasures for suppressing a rise in temperature of the magnets.

Abstract: An apparatus for generating electrical energy includes at least one fixedly mounted stator having a generally cylindrical cross-section and further including an inner periphery and an outer periphery. The apparatus additionally includes a rotor which is mounted for rotation relative to the stator about an axis. A plurality of field windings is mounted to the stator to extend about its periphery preferably in a serpentine manner. Further, the apparatus includes first and second groups of permanent magnets. The first group of permanent magnets is mounted to the rotor and is axially arranged about the axis such that the first group of magnets faces the inner periphery of the stator. The second group of magnets is mounted to the rotor and is arranged about the axis such that the second group of permanent magnets faces the outer periphery of the stator.

Abstract: A spindle motor comprises a soundproof wall formed on a stator outside a peripheral surface of a rotor. Noise generated inside the motor during the operation is cut off by the wall to be reduced remarkably. Since the soundproof wall has no influence on the volume of the motor, a slim-type motor can be realized.