US Patent No. 9,413,199

ROTOR OF ELECTRIC MOTOR WITH MAGNET HOLDING STRUCTURE AND ELECTRIC MOTOR INCLUDING THE ROTOR


Patent No. 9,413,199
Issue Date August 09, 2016
Title Rotor Of Electric Motor With Magnet Holding Structure And Electric Motor Including The Rotor
Inventorship Yohei Arimatsu, Yamanashi (JP)
Assignee Fanuc Corporation, Yamanashi (JP)

Claim of US Patent No. 9,413,199

1. A rotor of an electric motor comprising a plurality of magnets arranged in a circumferential direction,
the rotor further comprising a holding member provided concentrically with the rotor on a radially outside of the plurality
of magnets so as to hold the plurality of magnets,

the holding member including a plurality of tubular members arranged concentrically with one another and having diameters
different from one another, the respective tubular members having expanded diameters such that compressive holding force acts
on the magnets radially inwardly, as a result of elastic restorative force of the holding member,

wherein any two tubular members of the plurality of tubular members which are adjacent to each other in a radial direction
are configured such that one of the two tubular members has an interference larger than that of the other tubular member situated
on a radially outside.