Rotor endplate for permanent magnet motor, rotor assembly with endplates, motor with rotor endplates, and electric compressor with motor having endplates

A rotor assembly for a permanent magnet motor, comprising:

• a rotor;
• a pair of endplates at opposite axial ends of the rotor, each endplate including:
• a base plate having an outer circumference, an inner circumference and first and second portions, the base plate having a center axis and defining a base plane perpendicular to the center axis;
• a stiffening portion coupled to the first portion of the base plate and extending in a direction parallel to the center axis, the stiffening portion extends along the outer circumference of the base plate in the first portion;
• a counterweight portion coupled to, and extending from the inner circumference of the base plate in the second portion toward the center axis and being in the base plane.

A permanent magnet motor, comprising:

• a housing;
• a rotor rotarily coupled to the housing;
• a stator fixedly coupled to the housing;
• a pair of endplates at opposite axial ends of the rotor, each endplate including:
• a base plate having an outer circumference, an inner circumference and first and second portions, the base plate having a center axis and defining a base plane perpendicular to the center axis;
• a stiffening portion coupled to the first portion of the base plate and extending in a direction parallel to the center axis, the stiffening portion extends along the outer circumference of the base plate in the first portion;
• a counterweight portion coupled to, and extending from the inner circumference of the base plate in the second portion toward the center axis and being in the base plane.

An electric scroll compressor configured to compress a refrigerant, comprising:

• a housing defining an intake volume and a discharge volume;
• a refrigerant inlet port coupled to the housing and configured to introduce the refrigerant to the intake volume;
• a refrigerant outlet port coupled to the housing and configured to allow compressed refrigerant to exit the electric scroll compressor from the discharge volume;
• a permanent magnet motor mounted inside the housing, the permanent magnet motor including:
• a rotor rotarily coupled to the housing;
• a stator fixedly coupled to the housing;
• a pair of endplates at opposite axial ends of the rotor, each endplate including:
• a base plate having an outer circumference, an inner circumference and first and second portions, the base plate having a center axis and defining a base plane perpendicular to the center axis;
• a stiffening portion coupled to the first portion of the base plate and extending in a direction parallel to the center axis, the stiffening portion extends along the outer circumference of the base plate in the first portion;
• a counterweight portion coupled to, and extending from the inner circumference of the base plate in the second portion toward the center axis and being in the base plane;
• a drive shaft coupled to the rotor;
• and,
• a compression device coupled to the drive shaft and configured to receive the refrigerant from the intake volume and to compress the refrigerant as the drive shaft is rotated by the motor.