External cooling tube arrangement for a stator of an electric motor

Patent metadata

Field	Value
Publication number	US-9768666-B2
Application number	US-201214343670-A
Country	US
Kind code	B2
Filing date	Aug 15, 2012
Priority date	Sep 8, 2011
Publication date	Sep 19, 2017
Grant date	Sep 19, 2017

Abstract

A stator for an electric motor includes a substantially hollow-cylindrical stator stack provided with wire windings and an end winding, which adjoins the stator stack in the axial direction. The stator stack includes a number of slots, wherein a coolant line is inserted into the respective slot. To improve efficiency of the electric motor, a section of the respective coolant line extends into the region of the end winding.

First claim

What is claimed:

1. A stator for an electric motor, comprising:
an essentially hollow cylindrical stator stack having an axis and provided with wire windings, said stator stack having a number of slots;
an end winding adjoining the stator stack in an axial direction;
coolant lines configured as cooling coils each having a straight longitudinal section extending in the axial direction and inserted into a respective one of the slots, said coolant coils also each having an axial end section extending in a circumferential direction and located in into a region of the end winding,
the stator stack has a plurality of peripherally closed circumferentially spaced hollow spaces extending in the axial direction and located between the slots in which the straight longitudinal sections of the cooling coils are located, and improving heat conduction; and
a cooling plate forming a hollow cylinder surrounding the end winding and attached to the axial end section of the cooling coils at a radially outer side of the end winding such that the axial end sections of the cooling coils extend circumferentially over the cooling plate at a radially outer side of the cooling plate,
wherein each of the cooling coils has two such axial end sections which are spaced from each other in the axial direction and arranged on a radially outer surface of the cooling plate in contact with the radially outer surface of the cooling plate, and
wherein the cooling plate is configured not as a closed cylinder but instead has a gap extending in an axial direction and provided in a region in which the cooling coils do not have any tangentially spread regions extending over the gap.

2. The stator of claim 1 , wherein the coolant lines have each an inlet and an outlet, said inlet and outlet being arranged on a same axial side of the stator stack.

3. The stator of claim 1 , further comprising an electrical insulation provided for the section.

4. The stator of claim 1 , further comprising an electrical insulation provided for the cooling plate.

5. The stator of claim 1 , wherein the stator stack has a hollow space configured to extend in slot direction in a region that is not provided with a slot.

6. The stator of claim 1 , further comprising another cooling plate attached to an axially opposite axial end section of the cooling lines.

7. The stator of claim 1 , wherein the axial end section of the cooling coils is U-shaped and interconnects the straight longitudinal sections of the cooling coils.

8. The stator of claim 1 , wherein the axial end sections of at least two of the cooling coils are spaced from each other in the axial direction and arranged on a radially outer surface of the cooling plate in contact with the a radially outer surface of the cooling plate.

9. An electric motor, comprising a stator which includes an essentially hollow cylindrical stator stack having an axis and provided with wire windings, said stator stack having a number of slots, an end winding adjoining the stator stack in an axial direction, coolant lines configured as cooling coils each having a straight longitudinal section extending in the axial direction and inserted into a respective one of the slots, said coolant coils also each having an axial end section extending in a circumferential direction and located in a region of the end winding, the stator stack has a plurality of peripherally closed circumferentially spaced hollow spaces extending in the axial direction and located between the slots in which the straight longitudinal sections of the cooling coils are located, and improving heat conduction; and a cooling plate forming a hollow cylinder surrounding the end winding and attached to the axial end section of the cooling at a radially outer side of the end winding such that the axial end sections of the cooling coils extend circumferentially over the cooling plate at a radially outer side of the cooling plate, wherein each of the cooling coils has two such axial end sections which are spaced from each other in the axial direction and arranged on a radially outer surface of the cooling plate in contact with the radially outer surface of the cooling plate, and wherein the cooling plate is configured not as a closed cylinder but instead has a gap extending in an axial direction and provided in a region in which the cooling coils do not have any tangentially spread regions extending over the gap.

10. The electric motor of claim 9 , wherein the coolant lines have each an inlet and an outlet, said inlet and outlet being arranged on a same axial side of the stator stack.

11. The electric motor of claim 9 , wherein the stator has an electrical insulation provided for the section, the cooling plate or both.

12. The electric motor of claim 9 , further comprising another cooling plate attached to an axially opposite axial end section of the cooling lines.

13. The electric motor of claim 9 , wherein the axial end section of the cooling coils is U-shaped and interconnects the straight longitudinal sections of the cooling coils.

14. The stator of claim 9 , wherein the axial end sections of at least two of the cooling coils are spaced from each other in the axial direction and arranged on a radially outer surface of the cooling plate in contact with the a radially outer surface of the cooling plate.

15. A motor vehicle having an electric motor, said electric motor including a stator which includes an essentially hollow cylindrical stator stack having an axis and provided with wire windings, said stator stack having a number of slots, an end winding adjoining the stator stack in an axial direction, coolant lines configured as cooling coils each having a straight longitudinal section extending in the axial direction and inserted into a respective one of the slots, the stator stack has a plurality of peripherally closed circumferentially spaced hollow spaces extending in the axial direction and located between the slots in which the straight longitudinal sections of the cooling coils are located, and improving heat conduction, said coolant coils also each having an axial end section extending in a circumferential direction and located in a region of the end winding; and a cooling plate forming a hollow cylinder surrounding the end winding and attached to the axial end section of the cooling coils at a radially outer side of the end winding such that the axial end sections of the cooling coils extend circumferentially over the cooling plate at radially outer side of the cooling plate, wherein each of the cooling coils has two such axial end sections which are spaced from each other in the axial direction and arranged on a radially outer surface of the cooling plate in contact with the radially outer surface of the cooling plate, and wherein the cooling plate is configured not as a closed cylinder but instead has a gap extending in an axial direction and provided in a region in which the cooling coils do not have any tangentially spread regions extending over the gap.

16. The motor vehicle of claim 15 , wherein the coolant lines have each an inlet and an outlet, said inlet and outlet being arranged on a same axial side of the stator stack.

17. The motor vehicle of claim 15 , wherein the stator has an electrical insulation provided for the section, the cooling plate or both.

18. The motor vehicle of claim 15 , further comprising another cooling plate attached to an axially opposite axial end section of the cooling lines.

19. The motor vehicle of claim 15 , wherein the axial end section of the cooling coils is U-shaped and inter

Assignees

• BüTTNER KLAUS
• Kirchner Klaus
• Wöhner Norbert
• Siemens Ag

Inventors

• BüTTNER KLAUS
• Kirchner Klaus
• Wöhner Norbert

Classifications

• H02K5/203

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

• H02K9/14

  wherein gaseous cooling medium circulates between the machine casing and a surrounding mantle · CPC title

• H02K1/20 Primary

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

• H02K9/08

  by gaseous cooling medium circulating wholly within the machine casing (H02K9/10 takes precedence) · CPC title

• H02K9/18

  wherein the external part of the closed circuit comprises a heat exchanger structurally associated with the machine casing · CPC title