Rotary electric machine
A rotary electric machine includes a stator including teeth around which coils are wound, a rotor including a shaft of a hollow shape and a core member around which field windings are wound, the core member being coaxially fixed to the shaft, the rotor being disposed coaxially with the stator with a gap provided radially between the rotor and the stator, and a coolant flow passage structure communicating with a pump that force-feeds a liquid coolant, in which the field windings include coil turns located at axial ends of the rotor, the coolant flow passage structure includes a first coolant flow passage communicating with the interior of the shaft, and the first coolant flow passage extends radially outward from the shaft, passing axially inside the coil turns, and has a discharge opening radially facing the stator at a radially outer end.
1 . A rotary electric machine, comprising:
a stator including teeth around which coils are wound;
a rotor including a shaft of a hollow shape and a core member around which field windings are wound, the core member being coaxially fixed to the shaft, the rotor being disposed coaxially with the stator with a gap provided radially between the rotor and the stator; and
a coolant flow passage structure communicating with a pump that force-feeds a liquid coolant, wherein:
the field windings include coil turns located at axial ends of the rotor,
the coolant flow passage structure includes a first coolant flow passage communicating with an interior of the shaft,
the first coolant flow passage extends radially outward from the shaft, passing axially inside the coil turns, and has a discharge opening radially facing the stator at a radially outer end,
the rotor further includes an end member covering an axial end face of the core member,
the end member axially abuts, at part of an axially inner surface, the axial end face of the core member, and contacts, at an axially outer surface, the field windings,
the first coolant flow passage is formed between the axially inner surface of the end member and the axial end face of the core member,
the end member has an inner diameter side end that contacts the shaft and has a portion that extends radially outward from the inner diameter side end, and
in the portion that extends radially outward from the inner diameter side end of the end member, the first coolant flow passage is formed between the axially inner surface of the end member and the axial end face of the core member.
2 . The rotary electric machine according to claim 1 , wherein the discharge opening radially faces axial ends of the coils of the stator.
3 . The rotary electric machine according to claim 1 , wherein the first coolant flow passage includes a first flow passage extending annularly, and a plurality of second flow passages extending radially outward from the first flow passage.
4 . The rotary electric machine according to claim 3 , wherein one or more first holes in a radial direction are formed in an outer peripheral portion of the shaft, and
the one or more first holes are continuous with the first flow passage at a radially outer end.
5 . The rotary electric machine according to claim 4 , wherein the one or more first holes coincide in circumferential position with at least one of the plurality of second flow passages, or are circumferentially offset from the plurality of second flow passages.
6 . The rotary electric machine according to claim 1 , wherein
the coolant flow passage structure further includes a first coolant pipe having a first ejection opening at a position axially facing the coil turns of the field windings, and a second coolant pipe that allows supply of the liquid coolant from an axial end of the shaft to the interior of the shaft,
the liquid coolant supplied to the first coolant pipe is ejected axially from the first ejection opening of the first coolant pipe, and
the liquid coolant supplied to the second coolant pipe is supplied to the stator through the first coolant flow passage.
7 . The rotary electric machine according to claim 6 , wherein
the rotor further includes a cover member of a cylindrical shape covering the coil turns and the end member from radially outside, and
the first ejection opening of the first coolant pipe faces an axial end face of the cover member.
8 . The rotary electric machine according to claim 6 , wherein
the rotor further includes a cover member of a cylindrical shape covering the coil turns and the end member from radially outside,
the liquid coolant ejected axially from the first ejection opening is ejected from the first ejection opening to the coil turns,
one or more first holes in a radial direction are formed in an outer peripheral portion of the shaft, and
the liquid coolant ejected from the first ejection opening to the coil turns and the liquid coolant ejected from the first holes to the coil turns are supplied to axial ends of the coils of the stator through a second coolant flow passage formed by a gap between the coil turns or the end member and the cover member.
9 . The rotary electric machine according to claim 8 , wherein
the cover member includes a peripheral wall extending in a circumferential direction and an axial direction radially outside the coil turns, and an annular wall extending radially inward from an axial end of the peripheral wall,
the annular wall axially faces the coil turns from axially outside, and
the second coolant flow passage includes a third flow passage formed by a gap between the annular wall and the coil turns in the axial direction.
10 . The rotary electric machine according to claim 9 , wherein the first ejection opening of the first coolant pipe is located radially inside the annular wall.
11 . The rotary electric machine according to claim 9 , wherein
the end member includes a wall erected in the axial direction to radially face the coil turns from radially outside,
the cover member has a second hole in the radial direction at a position radially facing the axial ends of the coils of the stator,
the second coolant flow passage includes a fourth flow passage formed by a gap between the peripheral wall and the wall in the radial direction, and
the fourth flow passage communicates at one end with the third flow passage and communicates at an opposite end with the second hole in the cover member.
12 . The rotary electric machine according to claim 10 , wherein
the end member includes a wall erected in the axial direction to radially face the coil turns from radially outside,
the cover member has a second hole in the radial direction at a position radially facing the axial ends of the coils of the stator,
the second coolant flow passage includes a fourth flow passage formed by a gap between the peripheral wall and the wall in the radial direction, and
the fourth flow passage communicates at one end with the third flow passage and communicates at an opposite end with the second hole in the cover member.