US-20260128643-A1 - ROTATING ELECTRIC MACHINE SYSTEM

US20260128643A1US 20260128643 A1US20260128643 A1US 20260128643A1US-20260128643-A1

Abstract

In a rotating electric machine system, a rotor internal flow path that allows a liquid coolant to flow is formed in an interior of a rotor. At least one portion of a rotor internal flow path is formed between an outer peripheral surface of a rotating shaft and an inner peripheral surface of a sleeve. A support member being adjacent to an inner ring of a first bearing and configured to support a first sleeve end part is disposed between a first bearing and the sleeve. The sleeve is formed seamlessly from between the rotating shaft and permanent magnets, to the first sleeve end part that is supported by the support member.

Inventors

Tsubasa Nakatomi
Tatsuya Choji

Assignees

HONDA MOTOR CO., LTD.

Dates

Publication Date: 20260507
Application Date: 20251029
Priority Date: 20241101

Claims (7)

1 . A rotating electric machine system, comprising: a rotating electric machine including a rotor, the rotor including a permanent magnet and a rotating shaft; a rotating electric machine housing configured to rotatably support the rotating shaft; and a first bearing and a second bearing each interposed between the rotating electric machine housing and the rotating shaft, and configured to be spaced apart from each other in an axial direction of the rotor; wherein a rotor internal flow path through which a liquid coolant is allowed to flow is formed in an interior of the rotor; the rotor further includes a sleeve interposed between the rotating shaft and the permanent magnet in a radial direction of the rotating shaft, and at least a portion of the rotor internal flow path is formed between an outer peripheral surface of the rotating shaft and an inner peripheral surface of the sleeve; a support member that is adjacent to an inner ring of the first bearing and configured to support a first sleeve end part, which is one end part of the sleeve, is disposed between the first bearing and the sleeve; and the sleeve is configured to be formed seamlessly from between the rotating shaft and the permanent magnet to the first sleeve end part that is supported by the support member.
2 . The rotating electric machine system according to claim 1 , wherein the support member includes a supporting base part that is adjacent to the first bearing, and a supporting tubular part configured to project out from the supporting base part along an axial direction of the rotating shaft; and an outer peripheral surface of the supporting tubular part supports an inner peripheral surface of the first sleeve end part of the sleeve.
3 . The rotating electric machine system according to claim 2 , wherein an inner peripheral surface of the supporting tubular part forms one portion of the rotor internal flow path.
4 . The rotating electric machine system according to claim 1 , wherein a holder member having a hollow tubular shape and configured to surround the first sleeve end part is disposed outwardly of the first sleeve end part in the radial direction; and a seal member configured to face in the radial direction toward the holder member is disposed on an outer peripheral part of the first sleeve end part.
5 . The rotating electric machine system according to claim 4 , wherein the support member includes a supporting base part that is adjacent to the first bearing, and a supporting tubular part configured to project out from the supporting base part along an axial direction of the rotating shaft; an outer peripheral surface of the supporting tubular part supports an inner peripheral surface of the first sleeve end part of the sleeve; and a preload applying member configured to apply a load to an outer ring of the first bearing is disposed in a manner so as to surround the holder member, the seal member, and the supporting tubular part.
6 . The rotating electric machine system according to claim 1 , wherein the support member and the rotating shaft are fixed to each other by press fitting; and the support member and the sleeve are fixed to each other by press fitting.
7 . The rotating electric machine system according to claim 1 , wherein the sleeve is shrink-fitted onto an outer surface of the rotating shaft, and is also shrink-fitted onto a magnet stopper configured to fix the permanent magnet.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2024-192804 filed on November 1, 2024, the contents of which are incorporated herein by reference. BACKGROUND OF THE INVENTION FIELD OF THE INVENTION The present disclosure relates to a rotating electric machine system. DESCRIPTION OF THE RELATED ART A rotary electric machine includes a rotor having a rotating shaft, and a stator that is positioned on an outer circumference of the rotor. The rotor includes permanent magnets that are retained on the rotating shaft. When the rotating shaft rotates, an induced electrical current is generated in an electromagnetic coil that makes up the stator. In this case, the rotating electric machine functions as a generator. When the temperature of the permanent magnets becomes too high during the operation of the rotating electric machine, the magnetic force of the permanent magnets decreases. For example, in JP 2011-097784 A, in order to cool the permanent magnets, a configuration is disclosed in which a cooling medium (oil) is supplied to the interior of the rotating shaft. SUMMARY OF THE INVENTION It is undesirable for the cooling medium to leak out from any location other than a normal discharge outlet. The present invention has the object of solving the aforementioned problem. An aspect of the present disclosure is characterized by a rotating electric machine system, including a rotating electric machine including a rotor, the rotor including a permanent magnet and a rotating shaft, a rotating electric machine housing configured to rotatably support the rotating shaft, and a first bearing and a second bearing each interposed between the rotating electric machine housing and the rotating shaft, and configured to be spaced apart from each other in an axial direction of the rotor, wherein a rotor internal flow path through which a liquid coolant is allowed to flow is formed in an interior of the rotor, the rotor further includes a sleeve interposed between the rotating shaft and the permanent magnet in a radial direction of the rotating shaft, and at least a portion of the rotor internal flow path is formed between an outer peripheral surface of the rotating shaft and an inner peripheral surface of the sleeve, a support member that is adjacent to an inner ring of the first bearing and configured to support a first sleeve end part, which is one end part of the sleeve, is disposed between the first bearing and the sleeve, and the sleeve is configured to be formed seamlessly from between the rotating shaft and the permanent magnet to the first sleeve end part that is supported by the support member. In accordance with the rotating electric machine system according to the present disclosure, since there are no seams from between the rotating shaft and the permanent magnet to the first sleeve end part that is supported by the support member, the number of locations where leakage of the liquid coolant is capable of occurring is reduced. In accordance therewith, since leakage of the liquid coolant from any location other than the outlet of the rotor internal flow path can be suppressed, it is possible to suppress a situation in which an area inside the rotating electric machine housing into which the liquid coolant is not intended to flow becomes contaminated by the liquid coolant. The above and other objects, features, and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings, in which a preferred embodiment of the present invention is shown by way of illustrative example. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a combined motive power system; FIG. 2 is a schematic cross-sectional view of a rotating electric machine system; FIG. 3 is a schematic cross-sectional view of the rotating electric machine system as viewed from another angle; FIG. 4 is an enlarged cross-sectional view in the vicinity of a first bearing; and FIG. 5 is an enlarged cross-sectional view in the vicinity of a second bearing. DETAILED DESCRIPTION OF THE INVENTION A combined motive power system 10 shown in FIG. 1 includes a rotating electric machine system 12 according to the present embodiment, and a gas turbine engine 14. An axial line of the rotating electric machine system 12 and an axial line of the gas turbine engine 14 coincide with each other. Stated otherwise, the rotating electric machine system 12 and the gas turbine engine 14 are disposed in series on the same axial line. The combined motive power system 10 is used, for example, as a motive power source for providing propulsion in a flying object, a ship, an automobile, or the like. Suitable specific examples of the flying object include a drone and a multi-copter. The combined motive power system 10, when mounted on a flying object, is used as a power drive source for rotating, for exa