Patent ID: 11909276
Assignee: NIDEC CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  G | IPC H

Claim 0:
1. An electric motor, comprising:
a rotor assembly, which rotates about a vertical center axis extending in a vertical direction;
a stator assembly, which is provided around the rotor assembly;
terminals, which are connected electrically to the stator assembly;
a housing inside of which the stator assembly is fixed; and
a bearing mechanism, which rotatably supports the rotor assembly relative to the stator assembly; wherein
the housing includes:
a cylindrical wall portion, the stator assembly being located inside of the cylindrical wall portion;
a bottom which is provided at a bottom vertical end of the cylindrical wall portion and which extends radially outward; and
a cover plate which is on one side of the stator assembly that is opposite to the bottom; wherein

the cover plate is fixed to a radially inner side surface of the cylindrical wall portion and covers an opening of the cylindrical wall portion;
the bearing mechanism includes at least two bearings, one of the at least two bearings is supported by the cover plate and another one of the at least two bearings is supported by the bottom of the housing;
the cover plate includes electrically conductive elements and columnar projections fixed on the cover plate and protruding away from the stator assembly so that the columnar projections each directly or indirectly contact respective ones of grounding contacts of a controller which drives and controls the electric motor on one side of the cover plate, the controller being electrically connected to a ground potential through the housing; the cover plate includes terminal holes, each of the terminal holes passing through one of the terminals;
at least one of the terminal holes is arranged between two adjacent projections of the projections;
the columnar projections include a pin which is inserted and fixed in an insertion hole of the cover plate; and
a shape of the terminal holes is different from a shape of the insertion hole into which the pin is fixed when viewed in the vertical direction.