Hitachi, Ltd.

Hitachi Car Engineering Co., Ltd.

Kiyoshi Hirano

Suetaro Shibukawa

Keiji Oda

Fumio Tajima

Osamu Koizumi

Hiroshi Hamano

Yoshikazu Kadowaki

Plural magnet insertion holes are provided at a vicinity of an outer peripheral of a laminated rotor core toward a circumferential direction and extend toward an axial direction. The magnet insertion holes are divided into plural toward the axial direction and each of the plural magnet insertion holes is shifted at a predetermined angle toward a circumferential direction. The permanent magnet is arranged in the magnet insertion hole and the permanent magnet is fixed to the laminated rotor core through a clearance fill-up agent. The cogging torque is reduced and the reduction in noises is improved and a permanent magnet rotation type rotor constituted by low cost materials is prevented from damaging or destroying by the centrifugal force.

Permanent magnet rotation type rotary machine and manufacturing method

A dynamoelectric machine is provided with an arrangement in the form of a plurality of cooling tubes disposed in or adjacent the stator core of the machine and through which a coolant is caused to flow. The coolant tubes extend axially with respect to the rotor of the machine and are spaced around the circumference of the stator. In order to regulate the cooling efficiency and reduce the coolant pressure loss in the coolant tubes, a branching arrangement in combination with a valve arrangement is disposed in at least one of the end brackets of the machine to control the flow of coolant in parallel selectively through different combinations of cooling tubes. The branching arrangement includes a plurality of circumferentially disposed chambers which communicate with respective groups of cooling tubes in parallel, and the valve arrangement allows connection of these chambers selectively in different combinations to a coolant supply and a coolant exhaust. Thereby, the coolant tubes can be connected to form different combinations of parallel passages for carrying coolant to cool the stator of the machine.

Dynamoelectric machine

Growing community of inventors

Hitachinaka, Japan

Kiyoshi Hirano