Transmission for vehicle

Patent metadata

Field	Value
Publication number	US-2016298741-A1
Application number	US-201514819132-A
Country	US
Kind code	A1
Filing date	Aug 5, 2015
Priority date	Apr 7, 2015
Publication date	Oct 13, 2016
Grant date	—

Abstract

A transmission includes: a first input shaft selectively receiving power from an engine; a second input shaft continuously receiving power from the engine; a first output shaft arranged in parallel with the first input shaft and the second input shaft; a differential drawing power from the first output shaft and a second output shaft; a first shift unit providing desired gear shifts; a second shift unit to carry out duplicate gear shifts; and an one-way clutch to transmit power from the engine to the differential. In particular, the duplicate gear shifts has a gear ratio substantially identical to a gear ratio of one of the gear shifts made by the first shift unit, and the one-way clutch is arranged in a power transmission line for transmitting the power from the engine to the differential through the second shift unit.

First claim

What is claimed is:

1 . A transmission for a vehicle, comprising:
a first input shaft selectively receiving power from an engine; a second input shaft continuously receiving power from the engine; a first output shaft arranged in parallel with the first input shaft and the second input shaft; a differential drawing power from the first output shaft and a second output shaft; a first shift unit arranged between the first input shaft and the first output shaft, and between the first input shaft and the second output shaft, and configured to perform a series of desired gear shifts therebetween; a second shift unit arranged between the second input shaft and the first output shaft, and between the second input shaft and the second output shaft, and configured to perform a series of duplicate gear shifts therebetween, each duplicate gear shift having a gear ratio substantially identical to at least one gear ratio of the desired gear shifts of the first shift unit; and an one-way clutch arranged in a power transmission line for transmitting power from the engine to the differential through the second shift unit and configured to transmit the power from the engine only to the differential.

2 . The transmission according to claim 1 , wherein the first input shaft is a hollow shaft fitted around the second input shaft and connected to the engine through a clutch.

3 . The transmission according to claim 2 , wherein among the gear ratios of the desired gear shifts performed by the first shift unit and of the duplicate gear shifts, a largest gear ratio of the gear shifts of the first shift unit is substantially identical to a largest gear ratio of the duplicate gear shifts, and wherein a lowest gear ratio of the duplicate gear shifts is larger than a lowest gear ratio of the gear shifts of the first shift unit.

4 . The transmission according to claim 3 , wherein the first shift unit further comprises:
a plurality of first unit driving gears arranged on the first input shaft and configured to make the series of gear shifts; a plurality of first unit driven gears arranged on the first output shaft and the second output shaft configured to make the series of gear shifts by engaging with the first unit driving gears; and first unit synchronizers configured to allow or inhibit rotation of the first unit driven gears with respect to the first output shaft and the second output shaft, the first unit synchronizers arranged on the first output shaft and the second output shaft.

5 . The transmission according to claim 3 , wherein the second shift unit further comprises:
a plurality of second unit driving gears arranged on the second input shaft and configured to make the series of duplicate gear shifts; one or more second unit driven gears configured to make the series of duplicate gear shifts by engaging with the second unit driving gears, the second unit driven gears arranged on the first output shaft and the second output shaft; and second unit synchronizers configured to allow or inhibit rotation of the second unit driven gears with respect to the first output shaft and the second output shaft, the second unit synchronizers arranged on the first output shaft and the second output shaft.

6 . The transmission according to claim 5 , wherein the one-way clutch transmits power only from the second input shaft to the second unit driving gears, being arranged between the second input shaft and the second unit driving gears.

7 . The transmission according to claim 5 , wherein the one-way clutch transmits power only from the second unit driven gear to the second unit synchronizer, being arranged between the second unit driven gear and the second unit synchronizer.

8 . The transmission according to claim 7 , wherein the second unit driven gear includes a shift gear substantially generating a gear ratio by engaging with the second unit driving gear and a clutch gear connected to or disconnected from a second unit synchronizer by engaging with or disengaging from the second unit synchronizer, and
the one-way clutch is arranged between the shift gear and the clutch gear and transmits power only from the shift gear to the clutch gear.

9 . The transmission according to claim 5 , wherein a first output gear configured to transmit power to a differential by engaging with a ring gear of the differential is arranged on the first output shaft,
a second output gear configured to transmit power to the differential by engaging with the ring gear of the differential is arranged on the second output shaft, and one-way clutches are arranged between the first output shaft and the first output gear and between the second output shaft and the second output gear.

10 . The transmission according to claim 5 , wherein a hub of the second unit synchronizers comprises:
an inner hub fitted on the first output shaft or the second output shaft; and an outer hub arranged outside the inner hub to rotate relative to the inner hub and supporting a sleeve, and wherein the one-way clutch is arranged between the outer hub and the inner hub to transmit power only to the inner hub from the outer hub.

11 . The transmission according to claim 5 , wherein the one-way clutch is arranged between a flywheel and the second input shaft to transmit power only to the second input shaft from the flywheel of the engine.

12 . The transmission according to claim 1 , wherein the series of gear shifts performed by the first shift unit include a number N of gear shifts, and wherein the series of duplicate gear shifts performed by the second shift unit include a number M of gear shifts, and wherein M<=N.

Assignees

• Hyundai Motor Co Ltd

Inventors

• Eo Soon Ki
• Kim Hyun Chul
• Kim Chon Ok
• Lim Chae Hong

Classifications

• F16H37/0806 Primary

  with a plurality of driving or driven shafts · CPC title

• F16H2003/0931

  each countershaft having an output gear meshing with a single common gear on the output shaft · CPC title

• F16H3/10

  with one or more one-way clutches as an essential feature · CPC title

• F16H2003/007

  with two flow paths, one being directly connected to the input, the other being connected to the input through a clutch · CPC title

• F16H3/006 Primary

  power being selectively transmitted by parallel flow paths, e.g. dual clutch transmissions · CPC title