US 11,915,720 B2
Spindle motor and hard disk drive device
Hideaki Showa, Kitasaku-gun (JP); and Daigo Nakajima, Kitasaku-gun (JP)
Assigned to MINEBEA MITSUMI Inc., Nagano (JP)
Filed by MINEBEA MITSUMI Inc., Nagano (JP)
Filed on Mar. 2, 2023, as Appl. No. 18/177,340.
Claims priority of application No. 2022-042333 (JP), filed on Mar. 17, 2022.
Prior Publication US 2023/0298625 A1, Sep. 21, 2023
Int. Cl. G11B 19/20 (2006.01)
CPC G11B 19/2054 (2013.01) [G11B 19/2009 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A spindle motor comprising:
a shaft including a shaft member and a flange portion, the shaft member having a columnar shape extending in an axial direction, the shaft member including a shaft end portion, the flange portion being provided at the shaft end portion and receiving a load in the axial direction; and
a bearing sleeve rotatably supporting the shaft, the bearing sleeve having a tubular shape and including a sleeve end portion having a first opening part formed in the axial direction, wherein
the shaft is a member formed of a copper alloy containing from 0.5 mass percent to 1.5 mass percent of silicon and from 0.5 mass percent to 3.0 mass percent of manganese, and the member includes the shaft member and the flange portion integrated with one another.