Granted Patent B2

US 12,732,044 · App. 17/775,513 · Granted Sep 8, 2026

Inventors: Guillaume Tardy (La Celle St Cloud, FR); Diana Fantuz (Plaisir, FR)

Assignee: NIDEC PSA EMOTORS

H02K1/32H02K1/276H02K9/19H02K21/14

Abstract

Claims (31)

1 . A rotary electric machine with liquid cooling, comprising a rotor with magnets and a wound stator, the rotor comprising:

(i) at least one rotor sheet stack around a shaft of the rotor, the electric machine comprising axial cooling channels extending through the rotor sheet stack;

(ii) magnets housed in said sheet stack;

(iii) front and rear plates adjacent to said sheet stack, said front and rear plates each defining at least one supply channel and at least one discharge channel, said at least one supply channel of the front plate and of the rear plate being in fluid communication with a source of cooling liquid, the front and rear plates each coming to bear axially against said rotor sheet stack at one end, and the discharge channels being formed hollow on the face of the plate turned toward said rotor sheet stack, the discharge channels being formed by recesses whose depth, measured in an axial direction, increases toward the outer periphery of the front and rear plates, wherein the cooling liquid is configured to leave the rotor via the discharge channels;

wherein, a first one of said axial cooling channels is in fluid communication with the at least one supply channel in said front plate and the at least one discharge channel in said rear plate to allow flow of cooling liquid from said front plate to said rear plate; and

wherein, a second one of said axial cooling channels is in fluid communication with the at least one supply channel in said rear plate and the at least one discharge channel in said front plate to allow flow of cooling liquid from said rear plate to said front plate;

whereby, the machine is configured to enable a cross-flow of the cooling liquid within the rotor sheet stack.

2 . The machine according to claim 1 ,

(i)

(ii)

(iii)

wherein, the plates are supplied with cooling liquid by a shaft of the rotor, the shaft comprising a central channel and radial channels, this central channel communicating with the front plate by some of the radial channels and with the rear plate by other of the radial channels, the front and rear plates comprising supply channels having radial branches that are aligned with the radial channels of the shaft and open onto the radial channels of the shaft.

3 . The machine according to claim 1 ,

(i)

(ii)

(iii)

wherein the plates are supplied with cooling liquid via an axial distribution channel of the cooling liquid formed in the rotor mass along a shaft, the shaft being devoid of non-axial channels situated axially within the length of the sheet stack measured in the axial direction.

4 . The machine according claim 1 , each plate comprising at least one supply channel through which the liquid supplying the plate reaches at least one cooling channel.

5 . The machine according to claim 4 , the supply channel being formed hollow on the face of the plate facing the rotor sheet stack.

6 . The machine according to claim 4 , the supply channels each have a Y or T shape.

7 . The machine according claim 1 , the front and rear plates being identical and angularly offset so as to supply different cooling channels.

8 . The machine according to claim 7 , the cooling channels traversed by the liquid flowing from the front plate to the rear plate being made within odd poles, and/or those traversed by the liquid in the opposite direction being located within even poles.

9 . The machine according to claim 1 , the sheet stack defining housings which receive magnet(s); the cooling channels being formed by space left free by the magnet(s) in these housings.

10 . The machine according to claim 1 , the discharge channels being formed by recesses whose depth increases on approaching the outer periphery of the plate.

11 . The machine according to claim 1 , the supply and discharge channels alternating in the circumferential direction on each plate.

12 . The machine according to claim 1 , each discharge channel having a substantially trapezoidal shape.

13 . The machine according to claim 1 , the supply of the plates being done by the shaft of the rotor.

14 . The machine according to claim 1 , the discharge channels emerging opposite the coil heads of the stator.

15 . The machine according to claim 1 , each plate being a casting.

16 . The machine as defined in claim 1 , wherein the liquid is circulated in opposite directions within the rotor to cool the magnets, then the liquid is projected onto the coil heads of the stator after passing through the rotor sheet stack.

17 . The machine as defined in claim 2 , the central channel being branched to the radial channels only at axial positions of the shaft situated outside the length of the rotor sheet stack in the axial direction.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (14)