Rotating Electric Machine

• US 20070278869A1
• Filed: 01/10/2006
• Published: 12/06/2007
• Est. Priority Date: 01/17/2005
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Taketsuna, Yasuji
• Granted Patent: US 7,919,890 B2
• Time in Patent Office: Days
• US Class Current: 310/54
• CPC Class Codes: H02K 3/24 with channels or ducts for cooling medium between the conductors
• CPC Class Codes: H02K 9/19 for machines with closed casing and closed-circuit cooling using a liquid cooling medium, e.g. oil

Abstract

A rotating electric machine, comprising a stator, a rotor, a case storing the stator and the rotor, and an oil pump. Oil discharge ports are formed at the terminal part of an oil discharge passage of the case, and a cooling oil is supplied to the upper cutout parts of the stator. A groove part is covered by a cover to form a closed flow passage. Since the cooling oil is sufficiently applied to the portion of a coil exposed to the inside of the flow passage, a cooling efficiency is increased. Also the cooling oil is guided to an orifice on the lower side in the gravitational direction. Accordingly, since the cooling oil does not flow in an air gap between the rotor and the stator, a power loss can be prevented from occurring.

Claims

1. A rotating electric machine, comprising

a stator including a stator core and a coil wound around said stator core, and provided with a cooling flow passage arranged such that at least a portion of said coil wound around said stator core is dipped in a fluid for cooling;

and

a rotor arranged on an inner side of said stator core;

wherein

in said cooling flow passage, a fluid supply port is provided on an upper side of said stator core, and a fluid discharge port is provided on a lower side of said stator core;

said cooling flow passage is provided in a state closed from said fluid supply port to said fluid discharge port;

said rotating electric machine further comprising

a flow rate determining unit provided at said fluid discharge port, for determining a quantity of discharge of said fluid so that said cooling flow passage is appropriately filled with said fluid.

2. The rotating electric machine according to claim 1, wherein

said flow rate determining unit is a flow rate control valve attached to said fluid discharge port.

3. The rotating electric machine according to claim 2, comprising

a detecting unit for detecting a state of said rotating electric machine;

wherein

said flow rate determining unit changes coil dipping level of said fluid filled in said cooling flow passage in accordance with an output from said detecting unit.

4. The rotating electric machine according to claim 1, wherein

said flow rate determining unit is an orifice defining the quantity of discharge of said fluid.

5. A rotating electric machine, comprising:

a stator core;

a coil wound around said stator core; and

a resin mold portion fixing said coil on said stator core;

wherein

said resin mold portion molds said coil in such a state that a coil end portion as a part of said coil wound around said stator core is exposed and remaining portions are covered;

said rotating electric machine further comprising

a cover forming, with said resin mold portion, a cooling flow passage arranged such that said coil end portion is dipped in a fluid for cooling.

6. The rotating electric machine according to claim 5, wherein

in said cooling flow passage, a fluid supply port is provided on a lower side of said stator core, and a fluid discharge port is provided on an upper side of said stator core.

7. The rotating electric machine according to claim 6, further comprising

a check valve attached to said fluid supply port.

8. The rotating electric machine according to claim 6, wherein

said fluid discharge port is provided at a position allowing said fluid discharged from said fluid discharge port to be fed to a space between said stator core and a case accommodating said stator core.