Permanent magnet type rotary motor

Abstract

The objective of this invention is to balance the lightweight design and strength assurance of the rotor core of a permanent magnet type rotary electric motor. The permanent magnet type rotary electric motor of this invention comprises a fixed body and a rotating body inside the fixed body. The rotating body includes: a plurality of permanent magnets extending circumferentially along its outer periphery; and weight-reducing holes disposed on the inner diameter side of the permanent magnets, spanning the plurality of permanent magnets. The weight-reducing holes have a shape that is narrower between the permanent magnets and wider at their ends. The number of permanent magnets and weight-reducing holes is equal. The permanent magnets and weight-reducing holes are offset by half a pitch. The curvature of the outer diameter corner of the weight-reducing holes is in the range of R2.28 to R3.0, and the curvature of the inner diameter corner is in the range of R1.9 to R2.5.

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