公开(公告)号：US20190097488A1

公开(公告)日：2019-03-28

申请号：US16102817

申请日：2018-08-14

申请人： Nidec Corporation

发明人： Hiroki YAMADA ,  Atsushi WATASHITA ,  Keisuke KAWATA

IPC分类号： H02K5/16 ,  G11B19/20 ,  H02K3/52 ,  H02K7/08

摘要： A motor includes a shaft, a bearing that rotatably supports the shaft, and a hub fixed to the shaft. The shaft includes a first shaft portion extending in an axial direction, a second shaft portion projecting axially upward from an axially upper end surface of the first shaft portion and including a diameter smaller than that of the first shaft portion, and a screw hole recessed axially downward from the axially upper end surface. The hub includes a shaft fixing hole into and in which the second shaft portion is inserted and fixed. An outer surface of the second shaft portion includes a first region, and a second region axially above the first region, and including surface roughness smaller than that of the first region.