Electric machine with liquid cooling and method of assembling

A liquid cooled electric machine comprising:

• a housing;
• a shaft rotatably coupled to said housing;
• a rotor coupled to said shaft;
• a stator at least partially surrounding said rotor and defining an air gap between said stator and said rotor, said stator comprising:
• a stator body having an outer periphery and an inner periphery;
• at least one first coolant passage extending radially through said stator body from said outer periphery to said inner periphery, wherein said at least one first coolant passage facilitates providing a coolant to the air gap;
• at least one second coolant passage extending radially through said stator body;
• and
• at least one third coolant passage extending substantially annularly through said stator body intermediate the outer periphery and the inner periphery from said at least one first coolant passage to said at least one second coolant passage, wherein said at least one third coolant passage is fluidly coupled to said at least one first coolant passage and said at least one second coolant passage, said at least one second coolant passage extending from said at least one third coolant passage to said inner periphery;
• and
• a manifold fluidly coupled to said at least one first coolant passage, said manifold configured to deliver coolant to said at least one first coolant passage.

A method of assembling a liquid cooled electric machine, said method comprising:

• providing a housing;
• rotatably coupling a shaft to the housing;
• coupling a rotor to the shaft;
• orienting a stator to at least partially surround the rotor to define an air gap therebetween, the stator including a stator body having an outer periphery and an inner periphery;
• forming at least one first coolant passage in the stator body, the at least one first coolant passage extending radially between the outer periphery and the inner periphery, wherein the at least one first coolant passage facilitates providing a coolant to the air gap;
• forming at least one second coolant passage in the stator body, the at least one second coolant passage extending radially through the stator body;
• forming at least one third coolant passage in the stator body, the at least one third coolant passage extending substantially annularly through the stator body intermediate the inner periphery and the outer periphery from the at least one first coolant passage to the at least one second coolant passage, wherein the at least one third coolant passage is fluidly coupled to the at least one first coolant passage and the at least one second coolant passage, the at least one second coolant passage extending from the at least one third coolant passage to the inner periphery;
• and
• coupling a manifold to the first coolant passage in fluid communication with the at least one first coolant passage such that the manifold is configured to deliver coolant to the at least one first coolant passage.

A stator for use in a liquid cooled electric machine having a rotor, said stator comprising:

• a stator body having an outer periphery, an inner periphery, a first end face, and a second end face, said first end face configured for orientation adjacent to an end face of the rotor;
• at least one first coolant passage extending through said stator body, wherein said at least one first coolant passage facilitates providing a coolant to an air gap defined between said stator first end face and the rotor end face;
• at least one second coolant passage extending radially through said stator body from said outer periphery to said inner periphery;
• and
• at least one third coolant passage extending through the stator body intermediate the outer periphery and the inner periphery, said at least one third coolant passage extending substantially annularly about the entirety of said stator body, wherein said at least one third coolant passage is fluidly coupled to said at least one first coolant passage and said at least one second coolant passage, said at least one second coolant passage extending from said at least one third coolant passage to said inner periphery.