CN-114132168-B - Cooling structure for hybrid system of vehicle

CN114132168BCN 114132168 BCN114132168 BCN 114132168BCN-114132168-B

Abstract

A cooling structure for a vehicle hybrid system device may include a first rotor shaft coaxially connected to an engine output shaft and to a rotor of a first motor, an engine clutch shaft coaxially connected to the first rotor shaft without rotation and connected to an engine clutch, a transmission input shaft coaxially mounted with the engine clutch shaft to be rotated without rotation by a rotor of a second motor connected to the engine clutch, and a cooling passage formed in the transmission input shaft to supply oil for simultaneously cooling the first motor, the second motor, and the engine clutch.

Inventors

LIANG HONGSHUO
Jin Jingfan
LI XILUO
HE ZAIYUAN

Assignees

现代自动车株式会社
起亚自动车株式会社

Dates

Publication Date: 20260505
Application Date: 20210226
Priority Date: 20200903

Claims (10)

1. A cooling structure for a hybrid system device of a vehicle, the cooling structure comprising: A first rotor shaft connected to a rotor of the first electric machine and configured to be coaxially connected to an engine output shaft; an engine clutch shaft coaxially connected to the first rotor shaft and not rotating relative to the first rotor shaft, and connected to an engine clutch; A transmission input shaft mounted coaxially with the engine clutch shaft and not rotating relative to a rotor of a second electric machine connected to the engine clutch, and A cooling passage formed in the transmission input shaft to supply oil for cooling the first motor, the second motor, and the engine clutch; Wherein the engine clutch shaft and the first rotor shaft radially overlap each other to form an oil chamber for storing oil supplied through the cooling passage of the transmission input shaft; Wherein the engine clutch shaft is a hollow shaft, wherein an interior space of the hollow shaft is in fluid communication with the cooling passage of the transmission input shaft; wherein the first rotor shaft has a hole for receiving oil supplied through the engine clutch shaft and forming the oil chamber between the first rotor shaft and the engine clutch shaft, and Wherein a first cooling hole is formed in the first rotor shaft to supply oil in the oil chamber to the first motor, a second cooling hole is formed in the engine clutch shaft to supply oil in the oil chamber to the second motor, and a third cooling hole is formed in the transmission input shaft to supply the oil in the cooling passage to the engine clutch.
2. The cooling structure according to claim 1, Wherein the rotor of the first motor is fixed to a first rotor hub, Wherein the first rotor hub is connected to the first rotor shaft by an internal flange, and Wherein the first cooling hole supplies the oil to front and rear surfaces of the inner flange of the first rotor hub.
3. The cooling structure according to claim 2, Wherein the plurality of first cooling holes are formed to form a plurality of first cooling holes, Wherein a predetermined number of the first cooling holes are positioned at a front side of the inner flange of the first rotor hub in an axial direction of the first rotor hub to supply the oil on a front surface of the inner flange, and Wherein the remaining number of the first cooling holes are positioned at a rear side of the inner flange of the first rotor hub in an axial direction of the first rotor hub to supply the oil on a rear surface of the inner flange.
4. The cooling structure according to claim 1, Wherein the engine clutch is configured to selectively connect the engine clutch shaft and a rotor of the second electric machine.
5. The cooling structure according to claim 4, Wherein the rotor of the second electric machine is mounted radially outside the engine clutch and is fixed to a second rotor hub, Wherein the second rotor hub has a journal portion at the center, Wherein the inside of the journal portion is supported by a first bearing mounted between the journal portion and the engine clutch shaft, and the outside of the journal portion is supported on a housing by a second bearing, and Wherein the second cooling hole is positioned such that the oil from the oil chamber flows through the first bearing and the second bearing.
6. The cooling structure according to claim 5, wherein a first communication hole is formed in the journal portion of the second rotor hub such that oil passing through the first bearing flows into the second bearing.
7. The cooling structure according to claim 6, Wherein the second rotor hub has a sensor flange for mounting a resolver for detecting a position of the rotor of the second motor, and Wherein a second communication hole is formed in the sensor flange such that oil passing through the second bearing flows toward the rotor and stator of the second motor in a radial direction of the second rotor hub.
8. The cooling structure according to claim 5, Wherein the engine clutch includes a plurality of friction plates stacked between a clutch holder and a clutch hub of the engine clutch, Wherein the clutch hub is connected to the engine clutch shaft, Wherein the clutch retainer is connected to a connecting plate that connects the second rotor hub to the transmission input shaft, Wherein a third communication hole is formed in the clutch hub such that oil supplied from the third cooling hole flows through the plurality of friction plates via the third communication hole, and Wherein a fourth communication hole is formed in the clutch holder such that oil passing through the plurality of friction plates is discharged between the clutch holder and the second rotor hub via the fourth communication hole.
9. The cooling structure according to claim 8, wherein a fifth communication hole is formed in the second rotor hub portion such that the oil discharged from the fourth communication hole flows toward a stator of the second motor.
10. The cooling structure according to claim 7, wherein a sixth communication hole is formed on the second rotor hub portion such that an inner space of the engine clutch is fluidly connected to the second communication hole.

Description

Cooling structure for hybrid system of vehicle Technical Field The present invention relates to a cooling structure for a vehicle hybrid system. Background Hybrid powertrain systems can be categorized into flywheel-mounted electronic control devices (FMED) and transmission-mounted electronic control devices (TMEDs), each of which has advantages and disadvantages. The present invention relates to a power system that is not just of the FMED or TMED type, but utilizes a combination of the FMED and TMED types. That is, the present invention relates to a hybrid system in which a first motor is mounted on an output shaft of an engine, a second motor is mounted on an input shaft of a transmission, and the first motor and the second motor are connected through an engine clutch. The information included in the background section of the invention is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art that is known to a person skilled in the art. Disclosure of Invention Various aspects of the present invention are directed to providing a cooling structure capable of effectively cooling a first motor, a second motor, and an engine clutch, capable of improving durability of a vehicle, and capable of securing stable power transmission performance in a hybrid system of the vehicle, wherein the first motor is mounted on an output shaft of the engine, the second motor is mounted on an input shaft of the transmission, and the engine clutch is mounted between the first motor and the second motor. To achieve these objects, a cooling structure for a vehicle hybrid system according to various exemplary embodiments of the present invention may include a first rotor shaft coaxially connected to an engine output shaft and to a rotor of a first motor, an engine clutch shaft coaxially connected to the first rotor shaft and not rotating with respect to the first rotor shaft and connected to an engine clutch, a transmission input shaft mounted coaxially with the engine clutch shaft and not rotating with respect to a rotor of a second motor connected to the engine clutch, and a cooling passage formed in the transmission input shaft to be configured to supply oil for simultaneously cooling the first motor, the second motor, and the engine clutch. The engine clutch shaft and the first rotor shaft may radially overlap each other, forming an oil chamber for storing oil supplied through a cooling passage of the transmission input shaft. The engine clutch shaft may be a hollow shaft for communication with a cooling passage of the transmission input shaft, and the first rotor shaft may have a bore configured to receive oil supplied through the engine clutch shaft and form an oil chamber. A first cooling hole may be formed in the first rotor shaft to supply oil in the oil chamber to the first motor. The rotor of the first motor may be fixed to a first rotor hub portion, which may be connected to the first rotor shaft through an inner flange, and a plurality of first cooling holes axially spaced apart from each other may be formed to supply oil to both sides of the inner flange of the first rotor hub portion. A second cooling hole may be formed in the engine clutch shaft to supply the oil in the oil chamber to the second motor. The engine clutch may connect or disconnect the engine clutch shaft and the rotor of the second electric machine, and a third cooling hole may be formed in the transmission input shaft to supply oil in the cooling passage to the engine clutch. The rotor of the second electric machine may be disposed radially outside the engine clutch and fixed to the second rotor hub, the second rotor hub may have a journal portion at a center, an inner side of the journal portion may be supported by a first bearing disposed between the journal portion and the engine clutch shaft, an outer side of the journal portion may be supported on the housing by a second bearing, and the second cooling hole may be positioned such that oil from the oil chamber flows through the first bearing and the second bearing. The first communication hole may be formed in a journal portion of the second rotor hub such that oil passing through the first bearing flows into the second bearing. The second rotor hub may have a sensor flange for mounting a resolver for detecting a position of a rotor of the second motor, and a second communication hole may be formed in the sensor flange such that oil passing through the second bearing flows toward the rotor and the stator of the second motor in a radial direction of the second rotor hub. The engine clutch may be configured by stacking a plurality of friction plates between an inner clutch hub and an outer clutch holder, the clutch hub may be connected to an engine clutch shaft, the clutch holder may be connected to a connection plate that connects the second rotor hub to the tr