US-12627186-B2 - Rotor

US12627186B2US 12627186 B2US12627186 B2US 12627186B2US-12627186-B2

Abstract

The present teachings provide a rotor. The rotor 10 may comprise: a shaft 12 ; a rotor core 20 ; a first end plate 50 ; and a second end plate 52 . Rotor core 20 may comprise a first flow path 22 a which allows the coolant to flow from the one side to the other side of the axial direction and a second flow path 22 d which allows the coolant to flow from the other side to the one. First end plate 50 may comprise a first communication flow path 54 a which allows the coolant to flow from shaft 12 to first flow path 22 a . Second end plate 52 may comprise a second communication flow path 54 d which allows the coolant to flow from shaft 12 to second flow path 22 d.

Inventors

Hironori Asaoka
Hideaki Miyazono
Hiroki Kato
Fumiaki Yamato
Kiichi YOKOYAMA

Assignees

TOYOTA JIDOSHA KABUSHIKI KAISHA

Dates

Publication Date: 20260512
Application Date: 20231221
Priority Date: 20221228

Claims (7)

1 . A rotor, comprising: a shaft extending in an axial direction and through which coolant passes; a rotor core fixed to the shaft; a first end plate positioned on one side of the axial direction of the rotor core; and a second end plate positioned on another side of the axial direction of the rotor core, wherein the rotor core comprises a first flow path which allows the coolant to flow from the one side to the other side of the axial direction and a second flow path which allows the coolant to flow from the other side to the one side of the axial direction, the first end plate comprises a first communication flow path which allows the coolant to flow from the shaft to the first flow path and a first main discharging flow path which allows the coolant to flow from the shaft to outside, and the second end plate comprises a second communication flow path which allows the coolant to flow from the shaft to the second flow path and a second main discharging flow path which allows the coolant to flow from the shaft to outside, wherein the first main discharging flow path is configured to discharge the coolant in a radially outward direction from the shaft obliquely from the first end plate, toward an outer side in a radial direction of the rotor core and toward the one side of the axial direction, and the second main discharging flow path is configured to discharge the coolant in a radially outward direction from the shaft obliquely from the second end plate, toward the outer side in the radial direction of the rotor core and toward the other side of the axial direction.
2 . The rotor according to claim 1 , wherein the first end plate comprises the first communication flow path and the first main discharging flow path such that both of the flow paths are branched from each other, and the second end plate comprises the second communication flow path and the second main discharging flow path such that both of the flow paths are branched from each other.
3 . The rotor according to claim 2 , wherein the first communication flow path is configured to receive the coolant from the shaft and allow the coolant to flow to the first flow path and the first main discharging flow path is branched from the first communication flow path, and the second communication flow path is configured to receive the coolant from the shaft and allow the coolant to flow to the second flow path and the second main discharging flow path is branched from the second communication flow path.
4 . The rotor according to claim 3 , wherein the first communication flow path is configured such that a supply amount of the coolant to the first flow path is greater than the supply amount of the coolant to the first main discharging flow path, and the second communication flow path is configured such that the supply amount of the coolant to the second flow path is greater than the supply amount of the coolant to the second main discharging flow path.
5 . The rotor according to claim 1 , wherein the first end plate comprises a first auxiliary discharging flow path configured to discharge the coolant delivered through the second flow path, and the second end plate comprises a second auxiliary discharging flow path configured to discharge the coolant delivered through the first flow path.
6 . The rotor according to claim 1 , wherein the first flow path comprises a plurality of first flow paths, the second flow path comprises a plurality of second flow paths, and the rotor core comprises the plurality of first flow paths and the plurality of second flow paths alternately along a circumferential direction of the rotor core.
7 . The rotor according to claim 1 , wherein the first end plate and the second end plate have a same shape and are both fixed on the rotor core such that the first end plate and the second end plate are offset from each other by a predetermined angle about a rotary axis of the shaft.

Description

REFERENCE TO RELATED APPLICATION This application claims priority from Japanese Patent Application No. 2022-211915 filed on Dec. 28, 2022. The entire content of the priority application is incorporated herein by reference. TECHNICAL FIELD The art disclosed herein relates to a rotor. BACKGROUND A rotor and a stator of a stator to which a coil is fixed together constitute a motor. A rotor core is a cylindrical body holding magnet(s) therein and includes a rotor shaft at its center. Further, the rotor core has end plates respectively fixed to its one side and other side. When the motor operates, the magnet(s) and coil ends extending axially from the stator need to be cooled. As a conventional art of cooling magnets and coil ends, coolant from a rotor shaft is supplied to a rotor core via an end plate from one side in an axial direction of the rotor core. At the same time as this, the coolant supplied from this end plate is discharged outside to cool the coil ends (Japanese Patent Application Publication No. 2021-151098). SUMMARY However, according to such cooling structure with such flow of the coolant, the coolant supplied from the shaft is discharged as it is on the one side of the axial direction of the rotor core. On the other side of the axial direction of the rotor core, the coolant having passed through the rotor core is discharged via the end plate toward the coil end disposed on the other side. That is, the coolant having reached the respective coil ends had resulted in having different temperatures on the one side and on the other side of the axial direction of the rotor core. Due to this, the coil end on the other side could not be sufficiently cooled, and both sides of the axial direction could not be uniformly cooled. The present teachings provide an art of discharging coolant with a great cooling capability uniformly or at any arbitrary ratio on the one side and the other side of an axial direction of a rotor. The art disclosed herein is embodied by a rotor. The rotor may comprise: a shaft extending in an axial direction and through which coolant passes; a rotor core fixed to the shaft; a first end plate positioned on one side of the axial direction of the rotor core; and a second end plate positioned on another side of the axial direction of the rotor core. The rotor core may comprise a first flow path which allows the coolant to flow from the one side to the other side of the axial direction and a second flow path which allows the coolant to flow from the other side to the one side of the axial direction. The first end plate may comprise a first communication flow path which allows the coolant to flow from the shaft to the first flow path and a first main discharging flow path which allows the coolant to flow from the shaft to outside. The second end plate may comprise a second communication flow path which allows the coolant to flow from the shaft to the second flow path and a second main discharging flow path which allows the coolant to flow from the shaft to outside. According to the rotor disclosed herein, the first end plate located on the one side of the axial direction of the rotor allows the coolant from the shaft to flow on the one side of the axial direction along a direction from the one side to the other, and discharges the coolant outside on the one side of the axial direction. Also, the second end plate located on the other side of the axial direction of the rotor core allows the coolant from the shaft to flow on the other side of the axial direction along a direction from the other side to the one, and discharges the coolant outside on the other side of the axial direction. Due to this, on both the one side and the other side of the axial direction of the rotor core, the coolant which is yet to pass through the flow path in the rotor core, i.e., which has not yet absorbed heat, can be discharged outside. That is, on both the one side and the other side of the axial direction, the coolant with great cooling capability can be discharged outside of the rotor core. As a result of this, when the rotor is implemented in a motor for example, ends of a stator core of the motor on the one side and on the other side in the axial direction of the rotor core, in particular coil ends thereof, can be uniformly and effectively cooled. Further, the cooling capability of the coolant on the one side and the other side of the axial direction of the rotor core can be easily adjusted by adjusting the supply amount of the coolant for the first or second main discharging flow path. As a result of this, cooling performance for the coil ends on the one side and the other side of the axial direction of the rotor core can be easily adjusted. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an embodiment of a rotor disclosed herein with a stator, showing a cross-sectional view along an axial direction of a rotor core. FIG. 2A illustrates a plan view seen from an X side of the rotor core illustrated in F