New low-alloy steel compositions and rotor shafts for electric machines made from them are described. High nickel and chromium contents ensure high strength and toughness, while other components, notably silicon and other impurities, are kept low with the result that magnetic properties remain good. One aspect provides a steel with the following proportions by weight: and the remainder substantially Fe. Other aspects are also described.

This invention provides a rotary electric machine with a high productivity/maintainability.Since the shaft portion 43 or the stepwise drawn portion is formed with a flat face 47 perpendicular to the rotational axis, when the magnetic poles 42 are bonded to the rotor 40, an accurate gap control can be achieved by applying a certain pressure to the magnetic poles with a jig or the like using the perpendicular flat face 47 as reference, or by controlling the distance from the perpendicular flat fac...

In the portable electrical circular saw (electrical tool) in which a commutator motor (permanent magnet motor) is mounted in a motor case (housing) which is integrally formed in a tube shape, the commutator motor includes a stator fixed to an inner circumferential surface of the motor case and a rotor which is rotatably disposed in the stator, and a plate having a plurality of protrusions is disposed on at least one of the both axial ends of a rotor core of the rotor, an outer diameter of at lea...

A method for extending an event structure including submitting a keyname and a corresponding value for the event structure and determining whether the keyname exists in a keys field array of the event structure. If the keyname does not exist in the keys field array, the method includes incrementing an index of the event structure, adding the keyname to a position in the keys field array based on the index and adding the corresponding value to a position in the values field array based on the ind...

A rotor in an asynchronous electrical machine used in high speed applications, comprises an electrically conductive conductor surrounding a rotor shaft and located substantially adjacent to a stator of the asynchronous electrical machine, a coating layer made of a ferromagnetic particulate material having an electric conductivity substantially lower than that of the conductor, the coating layer being placed between the rotor shaft and the conductor and a metallic intermediate layer between the c...

A switched reluctance motor (M) comprises a stator assembly (SA) including a stator (S) having a central bore (B) and a plurality of inwardly extending salient teeth (ST). A plurality of stator windings (W) are installed on the stator teeth. A rotor assembly (RA) includes a (R) rotor mounted on a rotor shaft (RS) and installed in the central bore for rotation with respect to the stator assembly. The rotor assembly has a pluralitry of outwardly extending salient teeth (RT) with gaps (G) extending...

A vehicular alternator is provided which can effectively utilize the magnetic flux of a permanent magnet disposed between claw-type magnetic poles and can improve an output of the alternator. The vehicular alternator comprises a rotor and a stator constituted by coiling stator windings over a stator core, the rotor comprising a pair of claw-type magnetic poles arranged in an opposed relation, a permanent magnet disposed between adjacent two of a plurality of claws provided on the pair of claw-ty...

A permanent-magnet synchronous electric motor with isolated rotor for circulation pumps of heating and/or conditioning systems having: a motor casing; a stator in the motor casing and having associated coils; a housing tightly isolated from the stator for hosting a permanent-magnet rotor; a shaft integral with the rotor; and a bearing supporting the shaft in the housing. The bearing has a bush rotatively engaged by one end of the shaft, a sleeve inserted at one end of the housing and keyed onto ...

A rotor assembly for use in an electric motor or generator where the mass of the rotor assembly is reduced with respect to conventional rotor assemblies. In addition, the rotor assembly is configured to be scalable to different sized electric motors. Within the rotor assembly, the rotor hub, the shaft, and the permanent magnets can independently or collectively be modified to have a reduced mass. In one aspect, a portion of the rotor hub adjacent to the shaft is configured with passages and spok...

A rotor for an induction motor. The rotor includes a core, a pair of end rings, and a plurality of aluminum conducting members. The core includes a plurality of accommodating holes that are aligned circumferentially in a peripheral portion of the core. The accommodating holes extend from one end surface of the core to the other. The end rings are formed of aluminum alloy. Each of the end rings has a plurality of support holes corresponding to the accommodating holes. The support holes are aligne...