Power transmission system of hybrid electric vehicle

Patent metadata

Field	Value
Publication number	US-9701189-B2
Application number	US-201414500392-A
Country	US
Kind code	B2
Filing date	Sep 29, 2014
Priority date	Oct 29, 2013
Publication date	Jul 11, 2017
Grant date	Jul 11, 2017

Abstract

A power transmission system of a hybrid electric vehicle may include an engine being a power source, a torque transmission device including four rotation shafts and a compound planetary gear set, the torque transmission device converting torque input from the engine, and outputting a converted torque, two supplemental power sources respectively connected to two rotation shafts among the four rotation shafts of the torque transmission device and supplying generated torque to the torque transmission device, two friction members selectively connecting two rotation shafts among the four rotation shafts of the torque transmission device to a transmission housing, an output device outputting torque transmitted from the torque transmission device, and a final reducing device decelerating torque transmitted from the output device and outputting the decelerated torque through a differential apparatus.

First claim

What is claimed is:

1. A power transmission system of a hybrid electric vehicle comprising:
an engine being a power source;
a torque transmission device including four rotation shafts and a compound planetary gear set, the torque transmission device converting torque input from the engine, and outputting a converted torque;
two supplemental power sources respectively connected to two rotation shafts among the four rotation shafts of the torque transmission device and supplying generated torque to the torque transmission device;
two friction members selectively connecting two rotation shafts among the four rotation shafts of the torque transmission device to a transmission housing;
an output device including an output shaft outputting torque transmitted from the torque transmission device; and
a final reducing device, including a final reduction gear and a differential apparatus, decelerating torque transmitted from the output device through the final reduction gear and outputting the decelerated torque through the differential apparatus,
wherein the torque transmission device is the compound planetary gear set formed by combining a single pinion planetary gear set and a double pinion planetary gear set and having a ring gear and a planet carrier in common, and
wherein the four rotation shafts of the torque transmission device comprise:
a first rotation shaft including a first sun gear engaged with a short pinion, the first rotation shaft being connected to one of the two supplemental power sources, and selectively connected to the transmission housing;
a second rotation shaft including a common planet carrier and connected to an input shaft continuously or selectively;
a third rotation shaft including a common ring gear, connected to the other of the supplemental power sources, and connected to an intermediate output gear; and
a fourth rotation shaft including a second sun gear engaged with a long pinion and selectively connected to the transmission housing.

2. The power transmission system of claim 1 , wherein a torsional damper absorbing and reducing torsional vibration is disposed on the input shaft connecting the second rotation shaft with the engine.

3. The power transmission system of claim 2 , wherein an engine clutch is disposed between the second rotation shaft and the input shaft.

4. The power transmission system of claim 1 , wherein each of the two supplemental power sources comprises:
a first motor/generator directly connected to the first rotation shaft; and
a second motor/generator directly connected to the third rotation shaft.

5. The power transmission system of claim 1 , wherein the two friction members comprise:
a first brake disposed between the first rotation shaft and the transmission housing; and
a second brake disposed between the fourth rotation shaft and the transmission housing.

6. The power transmission system of claim 1 , wherein the output device comprises:
the output shaft disposed in parallel with and apart from the torque transmission device;
an intermediate input gear disposed on a first side portion of the output shaft and engaged with the intermediate output gear; and
a final output gear disposed on a second side portion of the output shaft.

7. A power transmission system of a hybrid electric vehicle comprising:
an engine being a power source;
a torque transmission device being a compound planetary gear set formed by combining a single pinion planetary gear set and a double pinion planetary gear set and having a ring gear and a planet carrier in common, wherein the torque transmission device includes:
a first rotation shaft having a first sun gear engaged with a short pinion and selectively connected to a transmission housing;
a second rotation shaft having a common planet carrier and connected to an input shaft receiving torque from the engine;
a third rotation shaft having a common ring gear and connected to an intermediate output gear; and
a fourth rotation shaft having a second sun gear engaged with a long pinion and selectively connected to the transmission housing;

a first supplemental power source including a first motor/generator directly connected to the first rotation shaft;
a second supplemental power source including a second motor/generator directly connected to the third rotation shaft;
a first friction member including a first brake disposed between the first rotation shaft and the transmission housing;
a second friction member including a second brake disposed between the fourth rotation shaft and the transmission housing; and
an output device including an output shaft decelerating torque transmitted from the torque transmission device and outputting the decelerated torque.

8. The power transmission system of claim 7 , further comprising a final reducing device including a final reduction gear and a differential apparatus, finally decelerating toque transmitted from the output device through the final reduction gear and transmitting the decelerated torque to the driving wheel through the differential apparatus.

9. The power transmission system of claim 7 , wherein a torsional damper absorbing and reducing torsional vibration is disposed on the input shaft connecting the second rotation shaft with the engine.

10. The power transmission system of claim 7 , wherein an engine clutch is disposed between the second rotation shaft and the input shaft.

11. The power transmission system of claim 7 , wherein the output device comprises:
the output shaft disposed in parallel with and apart from the torque transmission device;
an intermediate input gear disposed on a first side portion of the output shaft and engaged with the intermediate output gear; and
a final output gear disposed on a second side portion of the output shaft.

Assignees

• Hyundai Motor Co Ltd

Inventors

• Lee Hee Ra
• Byun Seonggon
• Kim Hyunsup
• Kim Baekyu
• Kim Insup
• Kim Seok Joon
• Ahn Chulmin

Classifications

• F16H2200/2038

  with three engaging means · CPC title

• F16H2037/103

  Power-split transmissions with each end of a CVT connected or connectable to a planetary gear set having four or more connections, e.g. a Ravigneaux set · CPC title

• B60K2006/381

  characterized by driveline brakes · CPC title

• F16H3/728

  with means to change ratio in the mechanical gearing · CPC title

• F16H2200/2023

  using a Ravigneaux set with 4 connections · CPC title