Rotating motor and motor-driven vehicle

• US 5,744,880 A
• Filed: 06/20/1996
• Issued: 04/28/1998
• Est. Priority Date: 06/20/1995
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Shibukawa, Suetato, Kawamata, Syouichi, Minakata, Rumi, Fukushima, Toshihiko, Koizumi, Osamu, Tajima, Fumio, Kudoh, Mitsuo
• Primary Examiner(s): Stephan, Steven L.
• Assistant Examiner(s): WALLACE, MICHAEL J
• Application Number:
  US08/668,266
• Time in Patent Office: 677 Days
• Field of Search: 310/89, 310/90, 310/91, 310/54, 310/58, 310/59, 310/64, 310/65
• US Class Current: 310/58
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 3/0061 relating to electrical machines
• CPC Class Codes: B60L 50/52 characterised by DC-motors
• CPC Class Codes: B60L 50/66 Arrangements of batteries
• CPC Class Codes: B60L 7/12 for vehicles propelled by dc motors
• CPC Class Codes: F16C 37/007 of rolling bearings
• CPC Class Codes: H02K 5/20 with channels or ducts for flow of cooling medium
• CPC Class Codes: H02K 5/203 specially adapted for liquids, e.g. cooling jackets
• CPC Class Codes: H02K 9/227 Heat sinks
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A rotating motor is provided which permits heat to be efficiently dissipated from all of the stator, rotor, and inner and outer races of bearings. This assures that the rotor exhibits a high intensity as it turns. Also, long bearing life is assured. A coolant enters a cooling passage formed in a first end bracket from entrance pipes and makes a half revolution, thus cooling a first one of the bearings. Also, the coolant cools the rotor via cooling disks and rotor disks. Then, the coolant flows into an outer surface-cooling passage in a motor housing and takes a zigzag course so as to make a substantially half revolution, thus cooling the stator. The coolant then flows into a cooling passage in a second end bracket and makes one revolution, thus cooling a second bearing. At the same time, the rotor is cooled via the cooling disks and rotor disks. Subsequently, the coolant enters another outer surface-cooling passage and makes a substantially half revolution, thus cooling the stator. The coolant then flows into another cooling passage in the aforementioned first end bracket and makes a substantially half revolution, thus cooling the first bearing again. Also, the rotor is cooled via the cooling disks and rotor disks.

Claims

1. A rotating motor comprising:

a rotating shaft having an outer surface and capable of rotating about an axis of rotation;

a rotor fixedly mounted on the outer surface of said rotating shaft and having an outer surface and a winding, said rotor having opposite ends extending in a direction of the axis of rotation;

a stator disposed around said rotor and having a winding;

a frame to which the outer surface of said stator is mounted;

end brackets mounted on said frame to form a case in which said rotor and said stator are housed and by which both ends of said rotating shafts are rotatably held via bearings;

stator-cooling mechanisms provided with coolant passages for cooling said stator; and

rotor-cooling mechanisms disposed close to at least one of said opposite ends of said rotor and provided with coolant passages for cooling said motor,

wherein on at least one of said opposite ends of said rotor taken in the direction of the axis of rotation there are provided substantially annular rotor disks to be cooled, wherein said rotor-cooling mechanisms are equipped with substantially annular cooling disks spaced apart from and disposed opposite to said rotor disks in the direction of the axis of rotation, and wherein said coolant passages are provided in said cooling disks.

2. The rotating motor of claim 1, wherein vertical cross-sectional shapes of the cooling surfaces of said cooling disks and of the cooled surfaces of said rotor disks taken in the direction of the axis of rotation are formed by protruding and recessed portions which are disposed opposite to each other.

3. The rotating motor of claim 1, wherein vertical cross-sectional shapes of the cooling surfaces of said cooling disks and of the cooled surfaces of said rotor disks taken in the direction of the axis of rotation are formed by substantially saw-toothed portions which are disposed opposite to each other.

4. The rotating motor of claim 1, wherein the coolant passages in said stator-cooling mechanisms and the coolant passages in said rotor-cooling mechanisms are connected to each other and permit a common coolant to flow therethrough.

7. The rotating motor of claim 2, wherein vertical cross-sectional shapes of the cooling surfaces of said cooling disks and of the cooled surfaces of said rotor disks taken in the direction of the axis of rotation are protruded and recessed portions which are opposite to each other.

8. The rotating motor of claim 2, wherein vertical cross-sectional shapes of the cooling surfaces of said cooling disks and of the cooled surfaces of said rotor disks taken in the direction of the axis of rotation are substantially saw-toothed portions which are opposite to each other.

5. A rotating motor comprising:

a rotating shaft having an outer surface and capable of rotating about an axis of rotation;

a rotor fixedly mounted on the outer surface of said rotating shaft and having an outer surface and a winding, said rotor having opposite ends extending in a direction of the axis of rotation;

a stator disposed around said rotor and having a winding;

a frame to which the outer surface of said stator is mounted;

end brackets mounted on said frame to form a case in which said rotor and said stator are housed and by which both ends of said rotating shafts are rotatably held via bearings;

stator-cooling mechanisms provided with coolant passages for cooling said stator;

bearing-cooling mechanisms mounted in said end brackets and provided with coolant passages for cooling said bearings; and

rotor-cooling mechanisms disposed close to at least one of said opposite ends of said rotor and provided with coolant passages for cooling said motor,

wherein on at least one of said opposite ends of said rotor taken in the direction of the axis of rotation there are provided substantially annular rotor disks to be cooled, wherein said rotor-cooling mechanisms are equipped with substantially annular cooling disks spaced apart from and disposed opposite to said rotor disks in the direction of the axis of rotation, and wherein said coolant passages are provided in said cooling disks.

6. The rotating motor of claim 5, wherein the coolant passages in said stator-cooling mechanisms, the coolant passages in said bearing-cooling mechanisms, and the coolant passages in said rotor-cooling mechanisms are connected to each other and permit a common coolant to flow therethrough.

9. A rotary motor comprising:

a rotary shaft on which is fixedly mounted a rotor having a winding;

a stator disposed around said rotor having a winding;

first and second end brackets by which the respective ends of said rotary shaft are supported for rotation around an axis of rotation via bearings;

a cylindrical housing forming with said first and second end brackets a case in which said rotor and stator are housed, said stator being mounted on an inner surface of said housing;

substantially annular first cooling disks provided on the opposite ends of said rotor taken in the direction of said axis of rotation;

substantially annular second cooling disks provided on said first and second end brackets in opposing, closely spaced relationship to said first cooling disks;

a first bracket cooling passage formed in said first end bracket, and having a cooling fluid entrance for introduction of cooling fluid, for cooling one of said bearings and at least a part of the second cooling disk provided in said first end bracket;

a first housing cooling passage formed in said cylindrical housing, and being connected at one end to said first bracket cooling passage, for cooling at least part of said stator;

a second bracket cooling passage formed in said second end bracket, and being connected to the other end of said first housing cooling passage, for cooling one of said bearings and the second cooling disk provided in said second end bracket;

a second housing cooling passage formed in said cylindrical housing, and being connected at one end to said second bracket cooling passage, for cooling at least part of said stator; and

a third bracket cooling passage formed in said end bracket, and being connected to the other end of said second housing cooling passage and having a cooling fluid outlet, for cooling one of said bearings and at least a part of the second cooling disk provided in said first end bracket;

whereby cooling fluid may flow on a path through said first bracket cooling passage, said first housing cooling passage, said second bracket cooling passage, said second housing cooling passage and said third bracket cooling passage to cause heat to be efficiently dissipated from all of stator, rotor and bearings.

10. A rotary motor according to claim 9, wherein each of said first and second housing cooling passages takes a zigzag course so as to extend for substantially a half revolution around said axis of rotation.

11. The rotary motor according to claim 9, wherein said first cooling disks are mounted in end rings of said rotor.

12. The rotary motor according to claim 9, wherein said first cooling disks are formed integrally with end rings of said rotor.

13. The rotary motor according to claim 9, wherein said first cooling disks are firmly mounted to end rings of said rotor.

14. The rotary motor according to claim 9, wherein vertical cross-sectional shapes of the cooling surfaces of said first cooling disks and of the cooled surfaces of said second cooling disks taken in the direction of the axis of rotation are formed by protruding and recessed portions which are disposed opposite to each other.

15. The rotary motor according to claim 9, wherein vertical cross-sectional shapes of the cooling surfaces of said first cooling disks and of the cooled surfaces of said second cooling disks taken in the direction of the axis of rotation are formed by substantially saw-toothed portions which are disposed opposite to each other.

16. The rotary motor according to claim 9, wherein said first cooling disks and said second cooling disks are made of a metal having a high coefficient of thermal expansion.

17. The rotary motor according to claim 16, wherein said material having a high coefficient of thermal expansion includes at least one of aluminum and copper.

18. The rotary motor according to claim 9, wherein an iron core included in said stator and said winding of said stator are integrally encased in a molding member that fills a space between the outer surface of said stator and the inner surface of said housing.

19. The rotary motor according to claim 18, wherein said molding member is made of a material having a high coefficient of thermal expansion.