Motor Cooling System

Patent metadata

Field	Value
Publication number	US-2016164378-A1
Application number	US-201414560950-A
Country	US
Kind code	A1
Filing date	Dec 4, 2014
Priority date	Dec 4, 2014
Publication date	Jun 9, 2016
Grant date	—

Abstract

A motor assembly with an integrated cooling system is provided in which a coolant (e.g., oil) is injected into a hollow region of the rotor shaft. The coolant is expelled out of the rotor shaft and into the motor enclosure via multiple thru-holes, thereby allowing efficient cooling of both the stator and the rotor assemblies.

First claim

What is claimed is:

1 . A motor assembly with an integrated cooling system, comprising:
a stator contained within a motor enclosure; a rotor shaft, wherein said rotor shaft passes between a first end cap and a second end cap of said motor enclosure; a rotor mounted to said rotor shaft, wherein said rotor shaft includes a hollow region; a coolant pump for injecting a coolant into said motor assembly; a coolant reservoir in fluid communication with said coolant pump; a coolant injection tube, wherein said coolant injection tube passes through an end portion of said rotor shaft and into said hollow region of said rotor shaft, wherein said coolant injection tube fluidly couples said coolant pump to said hollow region of said rotor shaft, wherein said coolant flowing through said coolant injection tube is injected by said coolant pump into said hollow region of said rotor; a first coolant passageway, wherein said first coolant passageway fluidly couples a region within said motor enclosure to said coolant reservoir, and wherein said coolant within said region of said motor enclosure flows into said coolant reservoir via said first coolant passageway; and a plurality of thru-holes integrated into said rotor shaft, wherein each of said plurality of thru-holes fluidly couples said hollow region of said rotor shaft to said region within said motor enclosure, wherein said coolant passing from said hollow region to said region within said motor enclosure directly contacts said stator and said rotor prior to flowing through said first passageway into said coolant reservoir.

2 . The motor assembly of claim 1 , said coolant injection tube further comprising a gearbox coolant coupling, wherein said gearbox coolant coupling fluidly couples said coolant injection tube to a gearbox, wherein said coolant flowing through said coolant injection tube is injected by said coolant pump into said gearbox via said gearbox coolant coupling, wherein a second coolant passageway fluidly couples said gearbox to said coolant reservoir, and wherein said coolant flowing into said gearbox from said coolant injection tube via said gearbox coolant coupling flows into said coolant reservoir via said second coolant passageway.

3 . The motor assembly of claim 1 , further comprising a seal interposed between a portion of said coolant injection tube and said end portion of said rotor shaft.

4 . The motor assembly of claim 1 , wherein said coolant injected into said motor assembly is pressurized.

5 . The motor assembly of claim 1 , wherein centrifugal force generated during rotor shaft rotation forces said coolant injected into said hollow region of said rotor shaft to be expelled out of said plurality of thru-holes and into said region within said motor enclosure.

6 . The motor assembly of claim 1 , said first passageway further comprising an intake aperture located within said region of said motor enclosure, wherein said intake aperture is located between said stator and an inner wall of said motor enclosure, and wherein said coolant within said region of said motor enclosure passes through said intake aperture and said first passageway before flowing into said coolant reservoir.

7 . The motor assembly of claim 1 , said plurality of thru-holes comprising at least one thru-hole located adjacent to a first end of said rotor and at least one thru-hole located adjacent to a second end of said rotor.

8 . The motor assembly of claim 1 , wherein an axis corresponding to each of said plurality of thru-holes is perpendicular to a cylindrical axis corresponding to said rotor shaft.

9 . The motor assembly of claim 1 , wherein an axis corresponding to each of said plurality of thru-holes is angled relative to a cylindrical axis corresponding to said rotor shaft.

10 . The motor assembly of claim 1 , further comprising a second coolant injection tube, wherein said second coolant injection tube fluidly couples said coolant pump to said region within said motor enclosure, wherein said coolant flowing through said second coolant injection tube is injected by said coolant pump directly into said region of said motor enclosure.

11 . The motor assembly of claim 10 , further comprising a plurality of nozzles incorporated into said motor enclosure, wherein each of said plurality of nozzles is fluidly coupled to said second coolant injection tube, and wherein said coolant passing through said second coolant injection tube into said motor enclosure via said plurality of nozzles directly contacts said stator and said rotor prior to flowing through said first passageway into said coolant reservoir.

12 . The motor assembly of claim 11 , wherein said plurality of nozzles are incorporated into a motor casing of said motor enclosure.

13 . The motor assembly of claim 11 , wherein at least a portion of said plurality of nozzles are located adjacent to a plurality of stator end windings corresponding to said stator.

14 . The motor assembly of claim 1 , further comprising a second coolant injection tube, wherein said second coolant injection tube fluidly couples a second coolant pump to said region within said motor enclosure, wherein said coolant flowing through said second coolant injection tube is injected by said second coolant pump directly into said region of said motor enclosure.

15 . The motor assembly of claim 14 , further comprising a plurality of nozzles incorporated into said motor enclosure, wherein each of said plurality of nozzles is fluidly coupled to said second coolant injection tube, and wherein said coolant passing through said second coolant injection tube into said motor enclosure via said plurality of nozzles directly contacts said stator and said rotor prior to flowing through said first passageway into said coolant reservoir.

16 . The motor assembly of claim 15 , wherein said plurality of nozzles are incorporated into a motor casing of said motor enclosure.

17 . The motor assembly of claim 15 , wherein at least a portion of said plurality of nozzles are located adjacent to a plurality of stator end windings corresponding to said stator.

18 . The motor assembly of claim 1 , wherein said coolant is comprised of an oil.

19 . The motor assembly of claim 1 , further comprising a coolant jacket surrounding at least a portion of said motor assembly, wherein a secondary coolant flows through said coolant jacket, and wherein a second cooling pump circulates said secondary coolant throughout said coolant jacket via a cooling conduit.

20 . The motor assembly of claim 19 , wherein said secondary coolant is comprised of a water-based coolant.

21 . The motor assembly of claim 19 , wherein said coolant jacket is integrated within a motor casing, wherein said motor casing corresponds to a portion of said motor enclosure.

22 . The motor assembly of claim 1 , wherein said coolant pump is comprised of an electric coolant pump.

23 . The motor assembly of claim 1 , wherein said coolant pump is comprised of a mechanical coolant pump, and wherein said mechanical coolant pump is powered by rotation of said rotor shaft.

Assignees

• Atieva Inc

Inventors

• Gauthier Jean-Philippe
• Mayer Jeremy
• Tang Yifan

Classifications

• H02K9/19 Primary

  for machines with closed casing and closed-circuit cooling using a liquid cooling medium, e.g. oil · CPC title

• H02K7/116

  with gears · CPC title

• H02K5/20

  with channels or ducts for flow of cooling medium · CPC title

• H02K5/203

  specially adapted for liquids, e.g. cooling jackets · CPC title

• B60K2001/006

  the electric motors · CPC title