Cooling structure for cooling a stator core of a rotating electrical machine and method of manufacturing the cooling structure

1. A cooling structure for cooling a stator core of a rotating electrical machine, the cooling structure comprising:

a stator core arranged along an outer periphery of a rotor fixed to a rotary shaft of a rotating electrical machine;

a stator frame extending along an outer peripheral surface of the stator core, the stator frame being configured to fix and support the stator core from the outer peripheral surface side thereof; and

a motor case having a small-diameter end portion on one side in an axial direction of the rotary shaft, the small-diameter end portion being welded with airtightness onto an outer peripheral surface of the stator frame so that the motor case forms a space, which is a coolant flow path, together with the outer peripheral surface of the stator frame,

wherein the stator frame comprises, at an end portion on another side in the axial direction of the rotary shaft, a flange portion protruding outward in a radial direction of the rotating electrical machine,

wherein the motor case comprises, at an end portion on the one side in the axial direction of the rotary shaft, a flange portion protruding outward in the radial direction, and

wherein the flange portion of the stator frame and the flange portion of the motor case are welded to each other with airtightness so that a joined surface is directed in the axial direction of the rotary shaft.

2. The cooling structure for cooling a stator core of a rotating electrical machine according to claim 1 , wherein the motor case comprises:

an extending portion formed at an end portion on another of both the sides in the axial direction of the rotary shaft, the extending portion extending inward in the radial direction; and

one of a bearing portion and a rotation detector for the rotary shaft, which is provided at an end of the extending portion.

3. The cooling structure for cooling a stator core of a rotating electrical machine according to claim 2 , wherein the extending portion is fixed to a rotating electrical machine supporting member with a fixing member.

4. The cooling structure for cooling a stator core of a rotating electrical machine according to claim 1 ,

wherein the motor case comprises, at an end portion on another of both the sides in the axial direction of the rotary shaft, an extending portion extending one of inward and outward in the radial direction of the rotating electrical machine, and

wherein the extending portion is fixed to a rotating electrical machine supporting member with a fixing member.

5. The cooling structure for cooling a stator core of a rotating electrical machine according to claim 1 , wherein, instead of welding the motor case to the stator frame with airtightness, the motor case is one of press-fitted and shrink-fitted to the stator frame, and a resin member is provided to an outer end of a fitted portion so as to secure airtightness of the coolant flow path.

6. The cooling structure for cooling a stator core of a rotating electrical machine according to claim 1 , wherein, instead of welding the motor case to the stator frame with airtightness, the motor case is fixed to the stator frame through welding without airtightness, and a resin member is provided to an outer end of a joined portion so as to secure airtightness of the coolant flow path.

7. A cooling structure for cooling a stator core of a rotating electrical machine, the cooling structure comprising:

a stator core arranged along an outer periphery of a rotor fixed to a rotary shaft of a rotating electrical machine;

a stator frame extending along an outer peripheral surface of the stator core, the stator frame being configured to fix and support the stator core from the outer peripheral surface side thereof and

a motor case having small-diameter end portions on both sides in an axial direction of the rotary shaft, the small-diameter end portions being welded with airtightness onto an outer peripheral surface of the stator frame so that the motor case forms a space, which is a coolant flow path, together with the outer peripheral surface of the stator frame

wherein the motor case comprises:

an extending portion formed at an end portion on one of both sides in the axial direction of the rotary shaft, the extending portion extending inward in a radial direction of the rotating electrical machine; and

one of a bearing portion and a rotation detector for the rotary shaft, which is provided at an end of the extending portion.

8. The cooling structure for cooling a stator core of a rotating electrical machine according to claim 7 , wherein the extending portion is fixed to a rotating electrical machine supporting member with a fixing member.

9. A cooling structure for cooling a stator core of a rotating electrical machine, the cooling structure comprising:

a stator core arranged along an outer periphery of a rotor fixed to a rotary shaft of a rotating electrical machine;

a stator frame extending along an outer peripheral surface of the stator core, the stator frame being configured to fix and support the stator core from the outer peripheral surface side thereof and

a motor case having small-diameter end portions on both sides in an axial direction of the rotary shaft, the small-diameter end portions being welded with airtightness onto an outer peripheral surface of the stator frame so that the motor case forms a space, which is a coolant flow path, together with the outer peripheral surface of the stator frame

wherein the motor case comprises:

a flow path portion extending along an outer periphery of the stator frame, the flow path portion being configured to form the coolant flow path together with the outer peripheral surface of the stator frame; and

flange portions formed at both ends of the flow path portion in the axial direction of the rotary shaft, the flange portions being welded to the stator frame

an extending portion formed at an end portion on one of both sides in the axial direction of the rotary shaft, the extending portion extending inward in a radial direction of the rotating electrical machine; and

one of a bearing portion and a rotation detector for the rotary shaft, which is provided at an end of the extending portion.

10. The cooling structure for cooling a stator core of a rotating electrical machine according to claim 9 , wherein the extending portion is fixed to a rotating electrical machine supporting member with a fixing member.

11. A cooling structure for cooling a stator core of a rotating electrical machine, the cooling structure comprising:

a stator core arranged along an outer periphery of a rotor fixed to a rotary shaft of a rotating electrical machine;

a stator frame extending along an outer peripheral surface of the stator core, the stator frame being configured to fix and support the stator core from the outer peripheral surface side thereof; and

a motor case having small-diameter end portions on both sides in an axial direction of the rotary shaft, the small-diameter end portions being welded with airtightness onto an outer peripheral surface of the stator frame so that the motor case forms a space, which is a coolant flow path, together with the outer peripheral surface of the stator frame,

wherein the motor case comprises, at an end portion on side in the axial direction of the rotary shaft, an extending portion extending inward in a radial direction of the rotating electrical machine, and

wherein the extending portion is fixed to a rotating electrical machine supporting member with a fixing member.