KR-20260064101-A - POWER TRAIN DEVICE OF ELECTRIC VEHICLE

KR20260064101AKR 20260064101 AKR20260064101 AKR 20260064101AKR-20260064101-A

Abstract

The present invention provides a power transmission device for an electric vehicle characterized in that a first planetary gear set, a second planetary gear set, a third planetary gear set, and a fourth planetary gear set are mounted inside a case so as to be connected to each other, and a sleeve moves in the first gear shift direction to restrain the first carrier of the first planetary gear set to achieve a first gear shift, or a sleeve moves in the second gear shift direction to restrain the first sun gear of the first planetary gear set to achieve a second gear shift, or a sleeve moves in the third gear shift direction to simultaneously mesh with the first sun gear and the first ring gear of the first planetary gear set to achieve a third gear shift.

Inventors

김진훈
김강문
김원
김택수
이수한
정기윤

Assignees

현대트랜시스 주식회사

Dates

Publication Date: 20260507
Application Date: 20241031

Claims (10)

A power transmission device for an electric vehicle characterized in that a first planetary gear set, a second planetary gear set, a third planetary gear set, and a fourth planetary gear set are mounted inside a case so as to be connected to each other, and a sleeve moves in the first gear shift direction to restrain the first carrier of the first planetary gear set to achieve a first gear shift, or a sleeve moves in the second gear shift direction to restrain the first sun gear of the first planetary gear set to achieve a second gear shift, or a sleeve moves in the third gear shift direction to mesh simultaneously with the first sun gear and the first ring gear of the first planetary gear set to achieve a third gear shift.
In Article 1, The above-mentioned first planetary gear set is, The first sun gear is provided with a hub, and an external gear is provided on the outer diameter of the hub, and a first planetary gear is arranged along the circumference of the external gear, and a first ring gear is provided to surround the first planetary gear, and the first planetary gear is engaged externally with the first planetary gear between the first sun gear and the first ring gear, and at the same time engaged internally with the first ring gear. The above second planetary gear set is, It includes a second sun gear provided on a motor shaft and a second planetary gear arranged along the circumference of the second sun gear, wherein the second planetary gear is engaged externally with the second sun gear between the second sun gear and the first planetary gear, and simultaneously engaged externally with the first planetary gear. The above third planetary gear set is, It includes a third sun gear connected to the first ring gear, a third planetary gear arranged along the circumference of the third sun gear, and a second ring gear surrounding the third planetary gear, wherein the third planetary gear is engaged externally with the third sun gear and internally with the second ring gear between the third sun gear and the second ring gear. The above-mentioned fourth planetary gear set is, A power transmission device for an electric vehicle comprising a fourth sun gear provided on the outer diameter portion of the second ring gear, a fourth planetary gear arranged along the circumference of the fourth sun gear, and a third ring gear surrounding the fourth planetary gear, wherein the fourth planetary gear is engaged externally with the fourth sun gear and simultaneously engaged internally with the third ring gear between the fourth sun gear and the third ring gear.
In Article 2, A power transmission device for an electric vehicle characterized in that the third carrier is fixed to the case, the first planetary gear is rotatably connected to the first carrier, the first carrier is positioned between the first sun gear and the first ring gear, the third planetary gear is rotatably connected to the second carrier, the second carrier is connected to the intershaft, and the fourth planetary gear is rotatably connected to the third carrier.
In Paragraph 3, A sleeve is mounted inside the above case, and one of the 1st, 2nd, and 3rd gear shifts is achieved by the operation of the sleeve, and The above sleeve is, A first meshing portion provided on the outer diameter; A second meshing portion provided on one side of the inner diameter portion; and A third meshing part provided on the other side of the inner diameter part; A power transmission system for an electric vehicle including
In Article 4, When shifting to 1st gear, A power transmission device for an electric vehicle characterized in that, as the sleeve moves in the first gear shift direction, the first meshing portion engages with the fourth meshing portion provided in the case, and the second meshing portion engages with the fifth meshing portion provided in the outer diameter portion of the first carrier.
In Article 5, When shifting to 2nd gear, A power transmission device for an electric vehicle characterized in that, as the sleeve moves in the second gear shift direction, the first meshing part engages with the fourth meshing part, and the second meshing part engages with the sixth meshing part provided on the outer diameter of the first sun gear.
In Article 6, When shifting to 3rd gear, A power transmission device for an electric vehicle characterized in that as the sleeve moves in the 3rd gear shift direction, the first meshing part separates from the fourth meshing part and is released from meshing, and the second meshing part engages with the sixth meshing part while the third meshing part engages with the seventh meshing part provided on the outer diameter of the first ring gear.
In Article 7, A power transmission device for an electric vehicle characterized in that the first meshing part and the fourth meshing part are composed of spline teeth, the second meshing part and the fifth and sixth meshing parts are composed of spline teeth, and the third meshing part and the seventh meshing part are composed of spline teeth.
In Paragraph 3, A power transmission device for an electric vehicle characterized in that the power transmitted to the second carrier is transmitted to one axle shaft via an intershaft, and the power transmitted to the third ring gear is transmitted to the other axle shaft.
In Article 1, The above sleeve is, A power transmission device for an electric vehicle characterized by being movable in any one of the 1st gear shift direction, 2nd gear shift direction, and 3rd gear shift direction by means of a transfer device.

Description

Power transmission device of an electric vehicle The present invention relates to a power transmission device for an electric vehicle. The demand for electric vehicles (fuel cell vehicles) for commercial vehicles, such as freight trucks and buses, is increasing due to exhaust gas regulations and the reduction of fossil energy consumption. In electric vehicles, the power from the drive motor can be transmitted to the drive wheels through the reduction gear and the axle. Conventional power electric (PE) systems of electric vehicles can be classified into a central motor type, which receives power from a drive motor and transmits it to the axle through a reduction gear, and an electric axle (E-Axle) type, which includes a drive motor, a reduction gear, and a differential gear for the axle. Compared to internal combustion engine vehicles, conventional electric vehicles require the Power Electric (PE) system—which combines the motor, inverter, and reduction gear—to be more compact due to factors such as the increased installation space for the battery pack. However, conventional electric vehicles had difficulty meeting the required performance with 1st and 2nd stage reduction gears due to the power train layout characteristics of the electric axle (E-Axle). In addition, when high-performance drive motors were applied, there were problems such as occupying a large amount of mounting space and increasing costs. FIG. 1 is a drawing showing the overall configuration according to a preferred embodiment of the present invention. FIG. 2 is a diagram showing the power flow during a first-stage shift according to a preferred embodiment of the present invention. FIG. 3 is a diagram showing the power flow during two-stage shifting according to a preferred embodiment of the present invention. FIG. 4 is a diagram showing the power flow during a three-stage transmission according to a preferred embodiment of the present invention. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, it should be noted that in assigning reference numerals to the components of each drawing, the same components are given the same reference numeral whenever possible, even if they are shown in different drawings. Furthermore, in describing the present invention, if it is determined that a detailed description of related known components or functions may obscure the essence of the present invention, such detailed description is omitted. Additionally, while preferred embodiments of the present invention will be described below, the technical concept of the present invention is not limited or restricted thereto and can be modified and implemented in various ways by those skilled in the art. FIG. 1 is a drawing showing the overall configuration according to a preferred embodiment of the present invention, FIG. 2 is a drawing showing the power flow during a first gear shift according to a preferred embodiment of the present invention, FIG. 3 is a drawing showing the power flow during a second gear shift according to a preferred embodiment of the present invention, and FIG. 4 is a drawing showing the power flow during a third gear shift according to a preferred embodiment of the present invention. As illustrated in FIGS. 1 to 4, the present invention may include a first planetary gear set (10), a second planetary gear set (20), a third planetary gear set (30), and a fourth planetary gear set (40) mounted inside a case (CS). The first planetary gear set (10) and the second planetary gear set (20) may be Ravigneaux-type planetary gear sets in which two different sun gears mesh with one planetary gear. The third planetary gear set (30) and the fourth planetary gear set (40) may be stacked planetary gear sets. The first planetary gear set (10) may include a first sun gear (11), a first planetary gear (12) that meshes with the first sun gear (11), a first ring gear (13) that meshes with the first planetary gear (12), and a first carrier (14) connected to the first planetary gear (12). A first sun gear (11) may have a hub (110) formed protruding from its center. An external gear (111) may be formed on the outer diameter of the hub (110). A plurality of first planetary gears (12) may be arranged along the circumference of the external gear (111). The first ring gear (13) may be configured to surround the first planetary gear (12). The first planetary gear (12) may be located between the first sun gear (11) and the first ring gear (13). The first planetary gear (12) can be engaged externally with the first planetary gear (12) and internally with the first ring gear (13) between the first sun gear (11) and the first ring gear (13). The first planetary gear (12) can be connected to the first carrier (14) by a pin (P). The pin (P) can be connected to the first carrier (14) by passing through the center of the first planetary gear (12). The first planetary gear (12) can rotate ar