Power transmission device for hybrid vehicle

A power transmission device for a hybrid vehicle may include: a cover part mounted on a vehicle body; two motor parts embedded in the cover part; two rotor parts mounted on the respective motor parts and rotated; a torsion damper part coupled to any one of the rotor parts, and connected to an engine part; a transfer part rotatably connected to the torsion damper part; a clutch part configured to selectively connect the other one of the rotor parts to the transfer part; and an output part connected to the clutch part, and configured to discharge power to a transmission.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from and the benefit of Korean Patent Application No. 10-2019-0171349, filed on Dec. 20, 2019, which is hereby incorporated by reference for all purposes as if set forth herein.

BACKGROUND

Field

Exemplary embodiments of the present disclosure relate to a power transmission device for a hybrid vehicle, and more particularly, to a power transmission device for a hybrid vehicle, which can reduce the whole length thereof even though double motors are applied thereto.

Discussion of the Background

In general, a power transmission device for a hybrid vehicle has a layout in which an automatic transmission, a motor, an engine and an ISG (Integrated Starter & Generator) are arranged in a line.

A hybrid vehicle which uses an engine and motor is started by the motor. When the vehicle is driven at a predetermined speed, a generator, i.e. an ISG starts the engine in order to use an output of the engine and an output of the motor at the same time.

The motor used in the power transmission device for a hybrid vehicle may be driven for electric driving of the vehicle, when the engine is not driven at the initial stage.

Recently, a hybrid vehicle has been developed, which includes two or more motors installed therein, in addition to the hybrid vehicle including one motor installed therein. For example, when two motors are arranged in a power transmission device for a hybrid vehicle, a first motor may be driven to start an engine, and a second motor may be driven for electric driving of the vehicle.

In the conventional hybrid vehicle, however, a torsion damper which is necessarily used to absorb shock caused by drivability of the engine is disposed between the motor and the engine. Thus, the whole length of the power transmission device for a hybrid vehicle is increased, and a separate mass for supporting the torsion damper needs to be installed. Therefore, there is a need for a device capable of solving the problem.

The related art of the present disclosure is disclosed in Korean Patent Application No. 2009-0020791 published on Feb. 27, 2009 and entitled “Power Transmission Device for Hybrid Vehicle”.

SUMMARY

Various embodiments are directed to a power transmission device for a hybrid vehicle, which can reduce the whole length thereof even though double motors are applied thereto.

In an embodiment, a power transmission device for a hybrid vehicle may include: a cover part mounted on a vehicle body; two motor parts embedded in the cover part; two rotor parts mounted on the respective motor parts and rotated; a torsion damper part coupled to any one of the rotor parts, and connected to an engine part; a transfer part rotatably connected to the torsion damper part; a clutch part configured to selectively connect the other one of the rotor parts to the transfer part; and an output part connected to the clutch part, and configured to discharge power to a transmission.

Each of the rotor parts may be disposed in the corresponding motor part, and the transfer part may be disposed on the rotation center axis of the rotor part.

The torsion damper part may be disposed between the rotor part and the transfer part.

The cover part may include: a cover outer wall having the motor parts mounted therein; and a cover inner wall extended inwardly from the cover outer wall.

The motor parts may include: a first motor part mounted in the cover part, and driven to start the engine part; and a second motor part mounted in the cover part, and driven to operate the vehicle.

The first motor part may be disposed closer to the engine part than the second motor part, and the second motor part may have larger power than the first motor part.

The rotor parts may include: a first rotor part rotated by the first motor part, and coupled to the torsion damper part; and a second rotor part rotated by the second motor part, and selectively connected to the clutch part.

The first rotor part may include: a first rotor rotation part rotated by the first motor part; a first rotor support part interlocked with the first rotor rotation part, and supported by the cover part; and a first rotor extension part extended from the first rotor support part, and supported by the cover part.

The second rotor part may include: a second rotor rotation part rotated by the second motor part; a second rotor support part interlocked with the second rotor rotation part, and supported by the cover part; and a second rotor extension part extended from the second rotor support part, and supported by the cover part.

The torsion damper part may include: a first damper part connected to the engine part, and welded to the first rotor part; and a second damper part connected to the first damper part, and spline-coupled to the transfer part.

In the power transmission device for a hybrid vehicle in accordance with the embodiment of the present disclosure, the torsion damper part may be disposed in the motor part, which makes it possible to reduce the whole length of the power transmission device. Furthermore, the torsion damper part may relieve shock applied to the engine part and the motor part.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

Hereinafter, a power transmission device for a hybrid vehicle will be described below with reference to the accompanying drawings through various exemplary embodiments. It should be noted that the drawings are not to precise scale and may be exaggerated in thickness of lines or sizes of components for descriptive convenience and clarity only. Furthermore, the terms as used herein are defined by taking functions of the invention into account and can be changed according to the custom or intention of users or operators. Therefore, definition of the terms should be made according to the overall disclosures set forth herein.

FIG.1is a block diagram schematically illustrating a power transmission device for a hybrid vehicle in accordance with an embodiment of the present disclosure, andFIG.2is a cross-sectional view schematically illustrating the power transmission device for a hybrid vehicle in accordance with the embodiment of the present disclosure. Referring toFIGS.1and2, a power transmission device for a vehicle in accordance with the embodiment of the present disclosure includes a cover part10, two motor parts20, two rotor parts30, a torsion damper part40, a transfer part50, a clutch part60and an output part70.

The cover part10is mounted on a vehicle body. The motor parts20are embedded in the cover part10, and driven when power is applied thereto. Any one of the two motor parts20may be used to start the vehicle, and the other one may be used to drive the vehicle.

The rotor parts30are mounted in the respective motor parts20and rotated. The torsion damper part40is coupled to any one of the rotor parts30, and serves to relieve shock. The torsion damper part40is coupled to an engine part100.

The transfer part50is rotatably connected to the torsion damper part40. The transfer part50may transfer the rotational force of the engine part100.

The clutch part60selectively connects the other of the rotor parts30to the transfer part50. The output part70is connected to the clutch part60and discharges power to a transmission200.

At this time, the torsion damper part40is disposed between the one of the rotor parts30and the transfer part50. That is, the rotor parts30are disposed in the respective motor parts20. The transfer part50is disposed on the rotation center axis of the rotor part30. Furthermore, the torsion damper part40is disposed between the one of the rotor parts30and the transfer part50. Such a structure can reduce the whole length of the power transmission device1for a hybrid vehicle.

The cover part10in accordance with the embodiment of the present disclosure includes a cover outer wall11and a cover inner wall12.

The motor parts20are mounted in the cover outer wall11. For example, the cover outer wall11may be fixed to the vehicle body, and have an internal space in which the motor parts20, the rotor parts30, the torsion damper part40, the transfer part50, the clutch part60and the output part70are embedded. The cover outer wall11may be connected to the transmission200.

The cover inner wall12is extended inwardly from the cover outer wall11. For example, the cover inner wall12may include a first inner wall121extended from the cover outer wall11and a second inner wall122extended from the first inner wall121.

Oil in the transmission200may be introduced into the space between the cover outer wall11and the cover inner wall12, in order to perform a cooling operation.

The motor parts20in accordance with the embodiment of the present disclosure include a first motor part21and a second motor part22.

The first motor part21is mounted in the cover part10, and driven to start the engine part100. For example, the first motor part21may be disposed on the right side of the cover inner wall12, and disposed closer to the engine part100than the second motor part22.

The second motor part22is mounted in the cover part10, and driven to operate the vehicle. For example, the second motor part22is disposed on the left side of the cover inner wall12, and has a larger capacity than the first motor part21. Thus, the second motor part22may provide larger power than the first motor part21.

The rotor parts30in accordance with the embodiment of the present disclosure include a first rotor part31and a second rotor part32.

The first rotor part31is rotated by the first motor part21, and coupled to the torsion damper part40. For example, the first rotor part31may include a first rotor rotation part311functioning as a rotor of the first motor part21, and a first rotor support part312interlocked with the first rotor rotation part311and supported by the cover inner wall12. The first rotor support part312has one end coupled to the torsion damper part40and the other end spline-coupled to the first inner wall121.

In addition, the first rotor part31may further include a first rotor extension part313. The first rotor extension part313may be extended from the first rotor support part312, and supported by the second inner wall122through one or more bearings in order to suppress movement.

The second rotor part32is rotated by the second motor part22, and selectively connected to the clutch part60. For example, the second rotor part32may include a second rotor rotation part321functioning as a rotor of the second motor part22, and a second rotor support part322interlocked with the second rotor rotation part321and supported by the cover inner wall12. The second rotor support part322may be spline-coupled to the first inner wall121.

In addition, the second rotor part32may further include a second rotor extension part323. The second rotor extension part323may be extended from the second rotor support part322, and supported by the second inner wall122through one or more bearings in order to suppress movement.

The torsion damper part40in accordance with the embodiment of the present disclosure may include a first damper part41and a second damper part42. The first damper part41and the second damper part42may be connected to each other, and each include a spring to absorb vibration when power generated by the engine part100and the first motor part21is transferred.

The first damper part41is coupled to the engine part100and welded to the first rotor part31. For example, the first damper part41may be coupled to the engine part100, and then welded to the first rotor support part312.

The second damper part42is connected to the first damper part41, and spline-coupled to the transfer part50. For example, when the first damper part41coupled to the engine part100is pressed against the first rotor support part312so as to be welded and coupled to the first rotor support part312, the second damper part42may be spline-coupled to the outer circumferential surface of the transfer part50, and thus transfer power.

The assembling process and the operation of the power transmission device for a hybrid vehicle in accordance with the embodiment of the present disclosure, which has the above-described structure, will be described as follows.

The second rotor part32is disposed in the second motor part22, and the clutch part60is disposed between the transfer part50and the second rotor part32. At this time, the second motor part22is mounted in the cover outer wall11, and the second rotor part32is supported by the cover inner wall12.

The first rotor part31is disposed in the first motor part21. At this time, the first motor part21is mounted in the cover outer wall11, and the first rotor part31is supported by the cover inner wall12.

After the engine part100and the first damper part41are coupled to each other, the first and second damper parts41and42are disposed in the first rotor part31. At this time, the second damper part42is spline-coupled to the transfer part50, and the first damper part41is welded to the first rotor part31.

According to the above-described assembly structure, the first damper part41and the second damper part42may be disposed in the first motor part21, which makes it possible to expect that the whole length of the power transmission device can be reduced. Since the first rotor part31and the first damper part41are directly connected to each other through welding, a separate mass for a damper may be omitted. That is, since the first rotor part31coupled to the first damper part41has a considerable weight, the first rotor part31may function as a mass for a damper. Furthermore, the structure in which the first and second damper parts41and42are doubly connected may be adopted for low stiffness. Therefore, the weight of the first damper part41can be reduced, and the structure can be simplified.

When the second motor part22is driven, the second rotor part32may be rotated, and the output part70connected to the clutch part60may transfer the rotational force of the second rotor part32to the transmission200, in order to drive the vehicle.

When the first motor part21is driven, the first rotor part31may be rotated, and the first damper part41connected to the first rotor part31may rotate the engine part100to induce a start-up of the engine part100.

When the engine part100is driven, the rotational force of the engine part100may be transferred to the transfer part50through the first and second damper parts41and42, and transferred to the output part70through the clutch part60, in order to drive the vehicle.

In the power transmission device1for a hybrid vehicle in accordance with the embodiment of the present disclosure, the torsion damper part40is disposed in the motor part20, which makes it possible to reduce the whole length of the power transmission device1. Furthermore, the torsion damper part40may relieve shock applied to the engine part100and the motor part20. As a person of ordinary skill in the art will understand, the cover part10, motor part20, rotor part30, transfer part50, clutch part60, output part70, engine part100, first motor part21, second motor part22, first rotor part31, second rotor part32, rotor rotation part311,321, rotor extension part313,323, and rotor support part321,322can be a housing, motor, rotor, transfer shaft, clutch, output shaft, engine, first motor, second motor, first rotor, second rotor, rotor, output shaft, and connecting plate between the rotor and the output shaft, respectively.