Rotary electric machine for vehicle

Patent metadata

Field	Value
Publication number	US-10418881-B2
Application number	US-201314020753-A
Country	US
Kind code	B2
Filing date	Sep 6, 2013
Priority date	Sep 7, 2012
Publication date	Sep 17, 2019
Grant date	Sep 17, 2019

Abstract

A rotary electric machine includes a rotor, a stator disposed facing the rotor in a radial direction having a stator core with a plurality of slots aligned in a circumferential direction and a stator winding wound around the slots of the stator core, and a cooling mechanism for cooling first and second coil-end groups of the stator winding by dropping a liquid coolant from an outer peripheral side thereof. The stator is disposed along an inner circumferential surface of at least one of the first and the second coil-end groups of the stator winding, and there is provided a shielding member for preventing the liquid coolant from falling into the inner circumferential side of the first and the second coil-end groups. Thus, it is possible to cool throughout the first and the second coil-end groups efficiently and reliably by the liquid coolant, a sufficient cooling effect can be obtained.

First claim

What is claimed is:

1. A rotating electric machine for a vehicle, the rotating electric machine comprising:
a rotor;
a stator disposed facing the rotor in a radial direction having a stator core with a plurality of slots aligned in a circumferential direction and a stator winding comprising a plurality of conductor segments welded together and wound around the slots of the stator core; and
a cooling mechanism for cooling a plurality of coil-end groups of the stator winding by dropping a liquid coolant from an outer peripheral side thereof; wherein,
the coil-end groups include a first coil-end group with a plurality of turn portions of the conductor segments stacked in a radial direction of the stator core and disposed in one axial end of the stator winding, and include a second coil-end group with a plurality of welded joint portions stacked in the radial direction of the stator core and disposed in another axial end of the stator winding;
four or a greater even number of the conductor segments are accommodated in each slot of the stator in a row in the radial direction, turn portions of the conductor segments electrically connect an Nth layer of one slot of the stator and an N+1 th layer of another slot that is separated from the one slot of the stator, and the conductor segments are disposed such that the turn portions in even numbered layers and odd numbered layers in each of the slots are inclined in opposite circumferential directions to each other and open end portions of the conductor segments are formed to be twisted by a half pole pitch in a circumferential direction on an outside of the stator core in an axial direction of the stator core;
the plurality of conductor segments that are in the first coil-end group are in contact with each other in a circumferentially adjacent manner;
the stator has a shielding member configured to prevent the liquid coolant from falling into the inner circumferential side of one of the coil-end groups, the shielding member being disposed only along an inner circumferential surface of the one of the coil-end groups;
the shielding member is formed in an annular shape;
the shielding member is formed of a resin material of a similar linear expansion coefficient to an insulating film of the conductor segments;
an outer diameter of the shielding member is larger than an inner diameter of the one of the coil-end groups;
the shielding member is attached to an inner peripheral side of the one of the coil-end groups by press-fitting; and
the inner peripheral side of the one of the coil-end groups is pressed radially outward by the shielding member, which reduces clearances inside the coil-end groups.

2. The rotating electric machine according to claim 1 , wherein,
the shielding member is adhered to the one of the coil-end groups using an adhesive agent.

3. The rotating electric machine according to claim 1 , wherein,
the shielding member is formed in a semicircular arc, and is attached to the one of the coil-end groups so that a central portion in a circumferential direction thereof is positioned where the liquid coolant is dropped.

4. The rotating electric machine according to claim 1 , wherein,
the stator winding has a straight portion extending in the axial direction accommodated in the slots of the stator core, and the straight portion is projected by a predetermined length from an end surface of the stator core.

5. A rotating electric machine for a vehicle, the rotating electric machine comprising:
a rotor;
a stator disposed facing the rotor in a radial direction having a stator core with a plurality of slots aligned in a circumferential direction and a stator winding comprising a plurality of conductor segments welded together and wound around the slots of the stator core; and
a cooling mechanism for cooling a plurality of coil-end groups of the stator winding by dropping a liquid coolant from an outer peripheral side thereof; wherein,
the coil-end groups include a first coil-end group with a plurality of turn portions of the conductor segments stacked in a radial direction of the stator core and disposed in one axial end of the stator winding, and include a second coil-end group with a plurality of welded joint portions stacked in the radial direction of the stator core and disposed in another axial end of the stator winding;
four or a greater even number of the conductor segments are accommodated in each slot of the stator in a row in the radial direction, turn portions of the conductor segments electrically connect an Nth layer of one slot of the stator and an N+1 th layer of another slot that is separated from the one slot of the stator, and the conductor segments are disposed such that the turn portions in even numbered layers and odd numbered layers in each of the slots are inclined in opposite circumferential directions to each other and open end portions of the conductor segments are formed to be twisted by a half pole pitch in a circumferential direction on an outside of the stator core in an axial direction of the stator core;
the plurality of conductor segments that are in the first coil-end group are formed in a stepped-shape and are in contact with each other in a circumferentially adjacent manner;
the stator has a shielding member configured to prevent the liquid coolant from falling into an inner circumferential side of the second coil-end group, the shielding member being disposed only along an inner circumferential surface of the second coil-end group among the coil-end groups;
the shielding member is formed in an annular shape;
the shielding member has a flange portion spreading outwardly in a radial direction from an outer end in an axial direction of the shielding member such that the shielding member covers the inner circumferential side of the second coil-end group and the axial end of the second coil-end group but does not cover an outer circumferential side of the second coil-end group, and an outer diameter of the flange portion is equal to or larger than an outer diameter of the second coil-end group;
the shielding member is formed of a resin material of a similar linear expansion coefficient to an insulating film of the conductor segments;
an outer diameter of the shielding member is larger than an inner diameter of the second coil-end group;
the shielding member is attached to an inner peripheral side of the second coil-end group by press-fitting; and
the inner peripheral side of the second coil-end group is pressed radially outward by the shielding member, which reduces clearances inside the coil-end groups.

Assignees

• Denso Corp

Inventors

• Tamura Akito

Classifications

• H02K3/24 Primary

  with channels or ducts for cooling medium between the conductors · CPC title

• H02K9/19

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

• H02K9/00 Primary

  Arrangements for cooling or ventilating (channels or ducts in parts of the magnetic circuit H02K1/20, H02K1/32; channels or ducts in or between conductors H02K3/22, H02K3/24) · CPC title