US 12,224,627 B2
Rotor assembly for an electric motor
Calahan B. Campton, Royal Oak, MI (US); Eric Bourniche, Preutin-Higny (FR); and James Bourn, Oxford, MI (US)
Assigned to BorgWarner Inc., Auburn Hills, MI (US)
Filed by BorgWarner Inc., Auburn Hills, MI (US)
Filed on Jul. 19, 2022, as Appl. No. 17/867,989.
Prior Publication US 2024/0030765 A1, Jan. 25, 2024
Int. Cl. H02K 1/32 (2006.01); H02K 7/116 (2006.01); H02K 9/193 (2006.01)
CPC H02K 1/32 (2013.01) [H02K 7/116 (2013.01); H02K 9/193 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A rotor assembly for an electric motor, said rotor assembly comprising:
a shaft extending along and rotatable about an axis, with said shaft defining a lubricant inlet channel for receiving a lubricant;
a lamination stack rotatably coupled to said shaft and extending along said axis between a first lamination stack end and a second lamination stack end, with said lamination stack at least partially defining a lubricant cooling channel between said first lamination stack end and said second lamination stack end and in fluid communication with said lubricant inlet channel;
a first end cap adjacent to said first lamination stack end; and
a second end cap adjacent to said second lamination stack end;
wherein one of said first end cap and said second end cap defines,
an end cap inlet at a first radial distance from said shaft for receiving the lubricant from said lubricant cooling channel,
a lubricant outlet channel for receiving lubricant from said end cap inlet, with said lubricant outlet channel defined to extend at least partially radially inward toward said shaft, and
an end cap outlet at a second radial distance from said shaft which is less than said first radial distance for receiving lubricant from said lubricant outlet channel and for expelling lubricant from said one of said first end cap and said second end cap,
wherein said first end cap defines a first end channel for receiving the lubricant from said lubricant inlet channel and for directing the lubricant to said lubricant cooling channel,
wherein said second end cap defines a second end channel for receiving the lubricant from said lubricant cooling channel, and
wherein said lubricant cooling channel is defined to include a first cooling pass extending between said first end channel and said second end channel and a second cooling pass extending from said second end channel toward said first end cap.