阅读说明：本技术 用于车辆的动力传输设备 (Power transmission apparatus for vehicle ) 是由 黄圣旭 孙宇哲 朴基宗 徐祥远 申容旭 池晟旭 金基兑 金千玉 赵源珉 康马禄 于 2018-12-12 设计创作，主要内容包括：本发明公开了用于车辆的动力传输设备。一种动力传输设备,包括：第一输入轴,总是从发动机接收输入扭矩；第二和第三输入轴,与第一输入轴共轴布置并且与第一输入轴选择性地连接；扭矩中间轴,与第一输入轴或变速器壳体选择性地连接；第一中间轴和第二中间轴以及输出轴,分别与第一输入轴平行布置；第一初步变速部,通过第一输入齿轮组接收扭矩,选择性地换挡所接收的扭矩,并且输出所变速的扭矩；第二初步变速部,包括第二变速齿轮组,该第二变速齿轮组从第一输入轴输出扭矩并且停止；以及复合变速部,通过输入扭矩以及第一和第二变速的扭矩形成输出扭矩。(The invention discloses a power transmission apparatus for a vehicle. A power transmission apparatus comprising: a first input shaft that always receives input torque from the engine; second and third input shafts arranged coaxially with the first input shaft and selectively connected thereto; a torque intermediate shaft selectively connectable with the first input shaft or the transmission housing; the first intermediate shaft, the second intermediate shaft and the output shaft are respectively arranged in parallel with the first input shaft; a first preliminary transmission portion that receives torque through the first input gear set, selectively shifts the received torque, and outputs the shifted torque; a second preliminary shift portion including a second speed change gear set that outputs torque from the first input shaft and stops; and a compound transmission portion forming an output torque by the input torque and the torques of the first and second speed changes.)

1. A power transmission apparatus for a vehicle, the power transmission apparatus comprising:

a first input shaft connected with an output shaft of the engine;

a second input shaft formed as a hollow shaft, which is coaxial with and arranged outside the first input shaft without rotational interference, and which is selectively connected with the output shaft of the engine;

a third input shaft formed as a hollow shaft, which is coaxial with and arranged outside the second input shaft without rotational interference, and which is selectively connected with the output shaft of the engine;

a torque intermediate shaft which is formed as a hollow shaft and which is coaxial with the first input shaft without rotational interference and is arranged outside the first input shaft, and which is selectively connected to the first input shaft or to a transmission housing;

a first intermediate shaft, a second intermediate shaft, and an output shaft arranged in parallel with the first input shaft, respectively;

a first preliminary shifting portion receiving torque through a first input gear set engaged with the third input shaft at an external gear, selectively shifting the received torque in gear ratios of a first speed gear set, and outputting the shifted torque;

a second preliminary shift portion including a second speed change gear set that outputs torque from the first input shaft and is stopped; and

a compound transmission portion including a planetary gear set having three rotary elements including a sun gear fixedly connected with the output shaft, forming an output torque based on a torque received from the second input shaft through a second input gear and torques received from the first and second preliminary transmission portions, and outputting the output torque through the output shaft.

2. The power transmission device according to claim 1, wherein:

the first input gear set comprises a first input driving gear and a first input driven gear, the first input driving gear is fixedly connected with the third input shaft, the first input driven gear is fixedly connected with the first intermediate shaft, and the first input driven gear is meshed with the first input driving gear through an external gear; and is

The first speed change gear set includes a first speed change driving gear coaxial with the first countershaft without rotational interference and disposed outside the first countershaft, and a first speed change driven gear fixedly connected to the second countershaft and meshed with the first speed change driving gear in an external gear.

3. The power transmission apparatus of claim 2 wherein the first speed drive gear is selectively coupled to the first intermediate shaft by a first synchronizer.

4. The power transmission apparatus of claim 2, wherein the gear ratio of the first speed gearset provides forward first gear speeds and forward fifth gear speeds.

5. The power transmission apparatus of claim 1, wherein the second preliminary transmission portion includes a second transmission drive gear coaxial with and disposed outside of the first input shaft.

6. The power transmission apparatus of claim 5 wherein said second speed drive gear is selectively connected to said torque intermediate shaft through a second synchronizer.

7. The power transmission device according to claim 1, wherein:

the planetary gear set of the compound transmission portion includes a ring gear, a carrier, and the sun gear;

the ring gear receives torque from the first and second preliminary transmissions through the second speed gearset;

the carrier receiving torque from the output shaft of the engine through the second input gear set; and is

The sun gear is selectively connectable with the ring gear and the sun gear is fixedly connectable with the output shaft to function as an output member.

8. The power transmission device according to claim 7, wherein:

the second input gear set comprises a second input driving gear and a second input driven gear, the second input driving gear is fixedly connected with the second input shaft, the second input driven gear is fixedly connected with the planet carrier, and the second input driven gear is meshed with the second input driving gear through an external gear; and is

The second speed change gear set includes a second speed change driving gear, an intermediate gear fixedly mounted on the second intermediate shaft, and a second speed change driven gear fixedly formed on the ring gear, and meshed with the second speed change driving gear and the intermediate gear, respectively, in an external gear.

9. The power transmission apparatus of claim 8, wherein a gear ratio of the second transmission drive gear and the second transmission driven gear provides a forward second speed and a forward fourth speed.

10. The power transmission device according to claim 1, further comprising:

four clutches, each clutch selectively connecting a corresponding pair of rotating members;

and

a brake selectively connecting the rotating member to the transmission housing.

11. The power transmission device according to claim 10, wherein:

the four clutches include:

a first clutch disposed between the output shaft of the engine and the third input shaft;

a second clutch disposed between the first input shaft and the torque intermediate shaft;

a third clutch disposed between the output shaft of the engine and the second input shaft; and

a fourth clutch disposed between the ring gear and the sun gear of the planetary gear set, and

wherein the brake is disposed between the torque intermediate shaft and the transmission housing.

12. The power transmission device according to claim 10, wherein:

the four clutches include:

a first clutch disposed between the output shaft of the engine and the third input shaft;

a second clutch disposed between the first input shaft and the torque intermediate shaft;

a third clutch disposed between the output shaft of the engine and the second input shaft;

a fourth clutch disposed between the ring gear and the sun gear of the planetary gear set, and

wherein the brake is disposed between the second intermediate shaft and the transmission housing.

13. The power transmission device according to claim 1, further comprising: a motor/generator coaxially coupled with the first input shaft, selectively connected with the output shaft of the engine through an engine clutch, and selectively connected with the second input shaft and the third input shaft through respective clutches.

14. The power transmission device according to claim 1, further comprising:

a motor/generator arranged in parallel with the first input shaft;

a motor drive gear receiving torque from the motor/generator;

a motor driven gear formed coaxially with the first input shaft; and

an idler gear meshed with the motor driving gear and the motor driven gear, respectively, and an external gear, respectively

Wherein torque from the motor/generator is transmitted to the first input shaft through the motor drive gear, the idler gear, and the motor driven gear.

15. The power transmission apparatus of claim 14, wherein the motor driven gear is fixedly coupled with the first input shaft, the motor driven gear is selectively connected with the output shaft of the engine through an engine clutch, and the motor driven gear is selectively connected with the second and third input shafts through respective clutches.

Technical Field

The present disclosure relates to a power transmission apparatus for a vehicle.

Background

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

The environment-friendly technology of vehicles is a core technology for controlling the survival of the future automobile industry, and advanced automobile manufacturers concentrate their efforts on developing environment-friendly vehicles to achieve regulation of environment and fuel efficiency.

Electric Vehicles (EV) or Hybrid Electric Vehicles (HEV) that utilize electric energy, or Dual Clutch Transmissions (DCT) that improve the efficiency and convenience of the transmission, may be examples of such future vehicle technologies.

The DCT includes a gear train of a manual transmission and two clutches. The DCT selectively transmits torque input from the engine to the two input shafts through the two clutches, changes the torque selectively transmitted to the two input shafts through the gear train, and outputs the changed torque.

The DCT is used to implement a compact transmission that achieves multiple forward speed steps over a five forward speed step. The DCT functions as an automated manual transmission that controls two clutches and a synchronizer through a controller, which does not require manual operation by a driver.

The DCT has excellent power transmission efficiency, simplifies changes and additions of components for realizing a plurality of gear stages, and improves fuel economy, as compared to an automatic transmission having a planetary gear set.

The above information disclosed in this background section is only for enhancement of understanding of the background of the disclosure and, therefore, it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art.

Disclosure of Invention

The present disclosure has been made in an effort to provide a power transmission apparatus for a vehicle having advantages of realizing a plurality of speed stages by adding one planetary gear set and two synchronizers to a dual clutch transmission structure, simplifying an internal structure thereof by reducing the number of components, improving fuel economy by reducing weight, and improving installability by reducing volume.

Additionally, an exemplary form of the present disclosure provides a power transmission apparatus that enables a vehicle to operate in an electric vehicle mode and a parallel hybrid mode by adding one motor/generator.

The power transmission apparatus for a vehicle according to various exemplary forms of the present disclosure may include: a first input shaft connected with an output shaft of the engine; a second input shaft formed as a hollow shaft, coaxial with and arranged outside the first input shaft without rotational interference, and selectively connected with an output shaft of the engine; a third input shaft formed as a hollow shaft, coaxial with and arranged outside the second input shaft without rotational interference, and selectively connected with an output shaft of the engine; a torque mediating shaft (torque mediating shaft) formed as a hollow shaft and coaxial with and arranged outside the first input shaft without rotational interference, and selectively connected with the first input shaft or the transmission housing; the first intermediate shaft, the second intermediate shaft and the output shaft are respectively arranged in parallel with the first input shaft; a first preliminary transmission portion receiving a torque through a first input gear set engaged with the third input shaft at an external gear, selectively shifting the received torque by a gear ratio of the first transmission gear set, and outputting the shifted torque; a second preliminary shift portion including a second speed change gear set that outputs torque from the first input shaft and stops; and a compound transmission portion including a planetary gear set having three rotary elements including a sun gear fixedly connected with the output shaft, the compound transmission portion forming an output torque based on a torque received from the second input shaft through the second input gear and torques received from the first preliminary transmission portion and the second preliminary transmission portion, and outputting the output torque through the output shaft.

The first input gear set may include a first input driving gear fixedly connected with the third input shaft and a first input driven gear fixedly connected with the first intermediate shaft and externally gear-engaged with the first input driving gear, and the first speed change gear set may include a first speed change driving gear coaxial with the first intermediate shaft without rotational interference and disposed outside the first intermediate shaft and a first speed change driven gear fixedly connected to the second intermediate shaft and externally gear-engaged with the first speed change driving gear.

The first speed drive gear may be selectively coupled to the first intermediate shaft by a first synchronizer.

The gear ratios of the first speed gearset may be used for forward first gear speeds and forward fifth gear speeds.

The second preliminary transmission portion may include a second transmission drive gear coaxial with and disposed outside of the first input shaft.

The second speed drive gear is selectively coupled to the torque intermediate shaft through a second synchronizer.

The planetary gear set of the compound transmission portion may include a ring gear that may receive torque from the first and second preliminary transmission portions through the second speed change gear set, a carrier that may receive torque from an output shaft of the engine through the second input gear set, and a sun gear that may be selectively connected with the ring gear and fixedly connected with the output shaft so as to function as an output element.

The second input gear set may include a second input driving gear fixedly connected with the second input shaft and a second input driven gear fixedly connected with the carrier and externally gear-engaged with the second input driving gear, and the second speed gear set may include a second speed driving gear, an intermediate gear fixedly mounted on the second intermediate shaft and a second speed driven gear fixedly formed on the ring gear and externally gear-engaged with the second speed driving gear and the intermediate gear, respectively.

The gear ratio of the second transmission driving gear and the second transmission driven gear may be used for the forward second speed and the forward fourth speed.

The power transmission apparatus may further include four clutches each selectively connecting a corresponding pair of the rotary members, and a brake selectively connecting the rotary members to the transmission case.

The four clutches may include a first clutch disposed between an output shaft of the engine and the third input shaft, a second clutch disposed between the first input shaft and the torque intermediate shaft, a third clutch disposed between the output shaft of the engine and the second input shaft, and a fourth clutch disposed between a ring gear and a sun gear of the planetary gear set, and the brake may be disposed between the torque intermediate shaft and the transmission housing.

The brake may be disposed between the second countershaft and the transmission housing.

The power transmission apparatus may further include a motor/generator coaxially coupled with the first input shaft, selectively connected with an output shaft of the engine through an engine clutch, and selectively connected with the second and third input shafts through respective clutches.

The power transmission device may further include a motor/generator arranged in parallel with the first input shaft, a motor driving gear receiving torque from the motor/generator, a motor driven gear formed coaxially with the first input shaft, and an idler gear externally gear-engaged with the motor driving gear and the motor driven gear, respectively, wherein torque from the motor/generator is fixedly transmitted to the first input shaft through the motor driving gear, the idler gear, and the motor driven gear.

The motor driven gear may be fixedly coupled with the first input shaft, selectively connected with an output shaft of the engine through an engine clutch, and selectively connected with the second and third input shafts through respective clutches.

The power transmission apparatus for a vehicle according to the first exemplary form is capable of realizing six forward speed gear stages by applying one planetary gear set and two synchronizers to a dual clutch transmission, and thus can realize multiple stages with a simpler structure and reduced weight, thus improving mountability and fuel consumption.

The power transmission apparatus for a vehicle according to the second and third example forms further employs one motor/generator than the first example form, and can be driven in an engine drive mode, a parallel hybrid mode, and an electric vehicle mode, thus further improving fuel consumption.

Further, the effects that may be obtained or expected from exemplary forms of the present disclosure will be described directly or implicitly in the detailed description that follows. That is, various effects expected from exemplary forms of the present disclosure will be described in the following detailed description.

Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

Drawings

In order that the disclosure may be fully understood, various forms thereof will now be described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a schematic illustration of a power transmission apparatus for a vehicle according to a first exemplary form of the present disclosure;

fig. 2 is a shift operation table of the power transmission apparatus for a vehicle according to the first example form of the disclosure;

FIG. 3 is a schematic illustration of a power transmission apparatus for a vehicle according to a second exemplary form of the present disclosure;

fig. 4 is a shift operation table of the power transmission apparatus for a vehicle according to a second example form of the disclosure;

FIG. 5 is a schematic illustration of a power transmission apparatus for a vehicle according to a third exemplary form of the present disclosure;

FIG. 6 is a schematic illustration of a power transmission apparatus for a vehicle according to a fourth exemplary form of the present disclosure; and

fig. 7 is a shift operation table of the power transmission apparatus for a vehicle according to a fourth example form of the disclosure.

The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

< description of symbols >

BK: brake

CL1, CL2, CL3, CL 4: first clutch, second clutch, third clutch, fourth clutch

CS1, CS 2: first intermediate shaft and second intermediate shaft

CT: composite speed changing part

FT1, FT 2: a first preliminary speed change portion and a second preliminary speed change portion

EOS: engine output shaft (crankshaft)

IG1, IG 2: a first input gear set and a second input gear set

IDG1, IDG 2: a first input driving gear and a second input driving gear

IPG1, IPG 2: first input driven gear, second input driven gear

IS1, IS2, IS 3: first input shaft, second input shaft, third input shaft

OG: output gear

And OS: output shaft

TG1, TG 2: first and second speed change gear sets

TDG1, TDG 2: a first speed change driving gear and a second speed change driving gear

TPG1, TPG 2: first speed-changing driven gear and second speed-changing driven gear

PG: planetary gear set

SN1, SN 2: first synchronizer and second synchronizer

TMS: torque intermediate shaft

Detailed Description

The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.

Those skilled in the art will recognize that the described forms may be modified in various different ways, all without departing from the spirit or scope of the present disclosure.

In the following description, since names of components are identical to each other, names of components are divided into first, second, and the like to distinguish the names of the components, and the order thereof is not particularly limited.

Fig. 1 is a schematic diagram of a power transmission apparatus for a vehicle according to a first example form of the present disclosure.

Referring to fig. 1, the power transmission apparatus includes: the hybrid transmission includes a first input shaft IS1, second and third input shafts IS2 and IS3, first and second countershafts CS1 and CS2, a first torque countershaft TMS, first and second preliminary shift portions FT1 and FT2, a compound shift portion CT, and an output shaft OS.

The engine ENG, which is a power source, may be implemented as various types of general engines, such as a gasoline engine or a diesel engine using fossil fuel.

The power transmission device according to the first exemplary form realizes six forward-speed shift stages. The torque of the engine ENG is shifted to a plurality of fixed speed change stages in the first preliminary speed change portion FT1 and the second preliminary speed change portion FT 2. The compound transmission section CT selectively receives torque from the first and second preliminary transmission sections FT1 and FT2 and also selectively receives torque from the engine ENG, and shifts the received torque and outputs an output torque through the output shaft OS.

The first, second and third input shafts IS1, IS2 and IS3 and the torque countershaft TMS are coaxially arranged. The first and second countershafts CS1, CS2 and the output shaft OS are arranged in parallel with the input shafts IS1, IS2, IS3 and the torque countershaft TMS. The torque of the engine ENG is transmitted to the first and second preliminary shift portions FT1 and FT2 and the compound shift portion CT. The synchronizers SN1 and SN are included in the first preliminary shift portion FT1 and the second preliminary shift portion FT2, respectively, and the planetary gear set PG is included in the compound shift portion CT.

The first input shaft IS1 IS fixedly connected to an output shaft EOS (crankshaft) of the engine ENG. The first input shaft IS1 selectively transmits torque of the engine ENG to the planetary gear set PG.

The second input shaft IS2 formed as a hollow shaft IS coaxial with and arranged outside the first input shaft IS1 without rotational interference and IS selectively connected with the output shaft EOS of the engine ENG. The second input shaft IS2 selectively transmits the torque of the engine ENG to the compound transmission portion CT.

The third input shaft IS3 formed as a hollow shaft IS coaxial with and arranged outside the second input shaft IS2 without rotational interference and IS selectively connected with the output shaft EOS of the engine ENG. The third input shaft IS3 selectively transmits torque of the engine ENG to the first intermediate shaft CS1 of the preliminary shift portion FT.

The torque intermediate shaft TMS IS formed as a hollow shaft and IS coaxial with and arranged outside the first input shaft IS 1.

The first preliminary shift portion FT1 includes first and second countershafts CS1 and CS2 and a first synchronizer SN 1.

The first countershaft CS1 IS in external gear engagement with the third input shaft IS3 through a first input gearset IG 1. The second countershaft CS2 may be connected in external gear engagement with the third input shaft IS3 through a speed change gear set TG 1.

The first input gearset IG1 includes a first input driving gear IDG1 and a first input driven gear IPG 1. The first input driving gear IDG1 IS fixedly connected to the third input shaft IS 3. The first input driven gear IPG1 is fixedly connected to the first countershaft CS1 and is in external gear engagement with the first input drive gear IDG 1.

The first shift gear set TG1 includes a first shift drive gear TDG1 and a first driven gear TPG 1. The first speed drive gear TDG1 is coaxial with and disposed outside of the first countershaft CS1 without rotational interference. The first driven gear TPG1 is fixedly connected to the second countershaft CS2 and is externally geared with the first change speed drive gear TDG 1.

The first synchronizer SN1 is configured to selectively synchronously connect the first shift drive gear TDG1 with the first countershaft CS 1.

The second preliminary shift portion FT2 includes a second synchronizer SN2 and the second synchronizer SN2 IS configured to selectively synchronously connect the torque countershaft TMS with a second shift drive gear TDG2 (which IS coaxial with and disposed outside of the first input shaft IS 1).

The compound transmission section CT includes a planetary gear set PG and an output shaft OS.

The planetary gear set PG is a single pinion planetary gear set, and includes a sun gear S, a planet carrier PC1 rotatably supporting a plurality of pinion gears P meshing with the sun gear S at an outer gear, and a ring gear R meshing with the plurality of pinion gears P at an inner gear.

The sun gear S is selectively connectable with the ring gear R and fixedly connectable with an output shaft OS serving as an output member. Planet carrier PC is fixedly connected with the second input driven gear IPG2 and selectively receives torque from the engine ENG. The ring gear R is fixedly connected with the second transmission driven gear TPG2 and selectively receives torque through the second synchronizer SN 2.

The planet carrier PC and the second input shaft IS2 are in external gear engagement via a second input gear set IG2, and the ring gear R IS in external gear engagement with a second speed gearset TG 2. The second input gearset IG2 includes a second input driving gear IDG2 and a second input driven gear IPG 2. The second input driving gear IDG2 IS fixedly connected to the second input shaft IS 2. The second input driven gear IPG2 is fixedly connected to the planet carrier PC and meshes with the second input driving gear IDG2 as an external gear.

The second shift gear set TG2 includes a second shift drive gear TDG2, a sun gear CG and a second shift driven gear TPG 2. The second shift drive gear TDG2 is coaxial with and disposed outside of the first countershaft CS1 without rotational interference. Sun gear CG is fixedly connected to second countershaft CS 2. The second shift driven gear TPG2 meshes with the second shift drive gear TDG2 and the sun gear CG as external gears.

The gear ratios in the first and second input gear sets IG1 and IG2, and the gear ratios of the drive and driven gears in the first and second speed gear sets TG1 and TG2 may be set appropriately in consideration of transmission requirements.

According to the first example form, in addition to the gear ratios in the first and second input gear sets IG1, IG2, the first speed gear set TG1 is involved in forming forward first gear speed FD1 and forward fifth gear speed FD5, and the second speed gear set TG2 is involved in forming forward second gear speed FD2 and forward fourth gear speed FD 4.

The output shaft OS is an output member, and transmits the shifted drive torque received from the planetary gear set PG to the differential DIFF through the output gear OG and the main reduction gear FDG.

Further, four engagement elements of the first clutch CL1, the second clutch CL2, the third clutch CL3, and the fourth clutch CL4 are disposed between a rotary member such as various shafts and a rotary element of the first planetary gear set PG, and one engagement element of the brake BK is disposed between the rotary member and the transmission housing H.

Five engaging elements of the four clutches CL1 to CL4 and the brake BK are arranged as follows.

The first clutch CL1 IS disposed between the engine output shaft EOS and the third input shaft IS3 to selectively connect the engine output shaft EOS and the third input shaft IS 3.

A second clutch CL2 IS disposed between first input shaft IS1 and torque countershaft TMS to selectively connect first input shaft IS1 and torque countershaft TMS.

The third clutch CL3 IS disposed between the engine output shaft EOS and the second input shaft IS2 to selectively connect the engine output shaft EOS and the second input shaft IS 2.

The fourth clutch CL4 is disposed between the ring gear R and the sun gear S (output shaft OS) to selectively connect the ring gear R and the sun gear S.

The fourth clutch CL4 enables the planetary gear set PG to integrally rotate.

The brake BK is arranged between the torque intermediate shaft TMS and the transmission case H, and thus the torque intermediate shaft TMS selectively serves as a stationary element.

The engaging elements first clutch CL1, second clutch CL2, third clutch CL3 and fourth clutch CL4, and brake BK may be implemented as a multi-plate hydraulic friction device frictionally engaged by hydraulic pressure, however, it should be understood that it is not limited thereto, as various other configurations that are electrically controllable may be employed.

The first synchronizer SN1 and the second synchronizer SN2 may be formed in a known structure, and the first sleeve SLE1 and the second sleeve SLE2 applied to the first synchronizer SN1 and the second synchronizer SN2 may be operated by respective actuators (not shown) that may be controlled by a transmission control unit.

Fig. 2 is a shift operation table of the power transmission apparatus for a vehicle according to the first example form of the disclosure, and the power transmission apparatus for a vehicle according to the first example form performs a shift operation as follows.

[ Forward first speed ]

In forward first gear speed FD1, first transmission drive gear TDG1 and first countershaft CS1 are interconnected in synchronization by sleeve SLE1 of first synchronizer SN1 and operate first clutch CL1 and fourth clutch CL4, as shown in fig. 2.

Then, by operating the first clutch CL1, the torque of the engine ENG IS input to the second ring gear R2 of the second planetary gear set PG2 through the third input shaft IS3, the first input driving gear IDG1, the first input driven gear IPG1, the first counter shaft CS1, the first speed change driving gear TDG1, the first speed change driven gear TPG1, the second counter shaft CS2, the sun gear CG and the second speed change driven gear TPG 2.

Further, the planetary gear set PG integrally rotates by the operation of the fourth clutch CL4, and outputs torque as input to the ring gear R, thus achieving the forward first speed FD1 and outputting the shifted torque to the differential DIFF through the output shaft OS.

That is, the forward first-speed is achieved by the first input driving gear IDG1, the first input driven gear IPG1, the first shift driving gear TDG1, the first shift driven gear TPG1, the intermediate gear CG and the second shift driven gear TPG 2.

[ Forward second speed ]

As shown in fig. 2, in the forward second speed FD2, the second change drive gear TDG2 and the torque countershaft TMS are synchronously connected through the sleeve SLE2 of the second synchronizer SN2, and the second clutch CL2 and the fourth clutch CL4 are operated.

Then, the torque of the engine ENG IS input to the first input shaft IS1 and the torque intermediate shaft TMS through the second clutch CL 2. In this state, the torque intermediate shaft TMS and the second speed drive gear TDG2 are connected to each other by the operation of the second synchronizer SN2, and the input torque is transmitted to the ring gear R of the planetary gear set PG through the second speed driven gear TPG 2.

Further, the planetary gear set PG integrally rotates by the operation of the fourth clutch CL4, and outputs torque as input to the ring gear R, thus achieving the forward second speed FD2 and outputting the shifted torque to the differential DIFF through the output shaft OS.

That is, the forward second speed is achieved by the gear ratio of the second shift driving gear TDG2 and the second shift driven gear TPG 2.

[ Forward three-speed ]

As shown in fig. 2, in the forward third speed FD3, the first synchronizer SN1 and the second synchronizer SN2 are in a neutral state (neutral state), and the third clutch CL3 and the fourth clutch CL4 operate.

Then, by the operation of the third clutch CL3, the torque of the engine ENG IS input to the planet carrier PC of the planetary gear set PG through the second input shaft IS2, the second input driving gear IDG2, and the second input driven gear IPG 2.

Further, the planetary gear set PG integrally rotates by the operation of the fourth clutch CL4, and outputs torque as input to the ring gear R, thus achieving the forward third speed FD3 and outputting the shifted torque to the differential DIFF through the output shaft OS.

That is, the forward third speed is achieved by the gear ratio of the second input driving gear IDG2 and the second input driven gear IPG 2.

[ Forward four-speed ]

As shown in fig. 2, in the forward fourth speed FD4, the second change drive gear TDG2 and the torque countershaft TMS are synchronously connected through the sleeve SLE2 of the second synchronizer SN2, and the second clutch CL2 and the third clutch CL3 are operated.

Then, the torque of the engine ENG IS partially input to the ring gear R of the planetary gear set PG through the first input shaft IS1, the torque intermediate shaft TMS through the operation of the second clutch CL2, the second transmission driving gear TDG2 through the operation of the second synchronizer SN 2.

Further, the torque of the engine ENG IS partially input to the planet carrier PC of the planetary gear set PG through the second input shaft IS2, the second input driving gear IDG2 and the second input driven gear IPG2 by the operation of the third clutch CL 3.

The planetary gear set PG then receives a different torque through the ring gear R and the planet carrier PC. In this state, the rotational speed input to the ring gear R is smaller than the rotational speed input to the planet carrier PC, and therefore, the planetary gear set PG outputs an increased rotational speed, thus achieving the forward fourth speed FD4 and outputting the shifted torque to the differential DIFF through the sun gear S and the output shaft OS.

[ Forward five-speed ]

As shown in fig. 2, in the forward fifth speed FD5, the first change speed drive gear TDG1 and the first countershaft CS1 are synchronously connected to each other through the sleeve SLE1 of the first synchronizer SN1, and the first clutch CL1 and the third clutch CL3 are operated.

Then, by operating the first clutch CL1, the torque of the engine ENG IS partially input to the second ring gear R2 of the second planetary gear set PG2 through the third input shaft IS3, the first input driving gear IDG1, the first input driven gear IPG1, the first counter shaft CS1, the first speed change driving gear TDG1, the first speed change driven gear TPG1, the second counter shaft CS2, the sun gear CG and the second speed change driven gear TPG 2.

Further, by operating the third clutch CL3, the torque of the engine ENG IS partially input to the planet carrier PC of the planetary gear set PG through the second input shaft IS2, the second input driving gear IDG2 and the second input driven gear IPG 2.

The planetary gear set PG then receives a different torque through the ring gear R and the planet carrier PC. In this state, the rotational speed input to the ring gear R is further smaller in the fourth forward speed than the rotational speed input to the planet carrier PC, and therefore, the planetary gear set PG outputs an increased rotational speed, thus realizing the fifth forward speed FD5 and outputting the shifted torque to the differential DIFF through the sun gear S and the output shaft OS.

[ Forward six-speed ]

As shown in fig. 2, in the forward sixth speed FD6, the second change speed drive gear TDG2 and the torque countershaft TMS are synchronously connected through the sleeve SLE2 of the second synchronizer SN2, and the third clutch CL3 and the brake BK are operated.

Then, the torque intermediate shaft TMS is fixed by the operation of the brake BK.

Because the second speed drive gear TDG2, which is connected to the torque countershaft TMS through the sleeve SEL2, is stationary (stationary), the second speed driven gear TPG2, which is fixedly connected to the ring gear R, is also stationary (stationary) such that the ring gear R acts as a stationary element.

Although the ring gear R is used as a fixed element, torque of the engine ENG is input to the planet carrier PC of the planetary gear set PG by the operation of the third clutch CL 3.

Then, the ring gear R is stationary compared with the rotational speed input to the planet carrier PC, and therefore, the planetary gear set PG outputs a rotational speed further increased than that in the forward fifth speed, thus achieving the forward sixth speed FD6 and outputting the shifted torque to the differential DIFF through the sun gear S and the output shaft OS.

Fig. 3 is a schematic diagram of a power transmission apparatus for a vehicle according to a second example form of the disclosure.

Referring to fig. 3, the second example form further includes a motor/generator MG as an auxiliary power source, as compared with the first example form, so that the vehicle to which the power transmission device is applied may be able to be driven in a parallel hybrid manner and an electric vehicle mode.

The motor/generator MG can function as a motor and as a generator, and includes a stator ST fixed to the transmission case H and a rotor RT rotatably supported within the stator ST.

The motor/generator MG is arranged behind the engine ENG. The rotor RT IS selectively connected with an output shaft EOS of the engine ENG intervening the engine clutch ECL, IS fixedly connected with the first input shaft IS1, and IS selectively connected with the second input shaft IS2 and the third input shaft IS3 intervening the first clutch CL1 and the third clutch CL 3.

When the engine clutch ECL is operated, the driving torque of the engine ENG is input to the power transmission device. In this state, the torque of the motor/generator MG can also be applied, so a drive mode of a parallel hybrid drive mode in which both the engine torque and the motor torque are used to drive the vehicle can be realized.

When the engine clutch ECL is released, the torque of the motor/generator MG can be used as the sole power source, and the vehicle can be driven in an electric vehicle mode (EV).

Fig. 4 is a shift operation table of the power transmission apparatus for a vehicle according to the second example form of the disclosure, and the power transmission apparatus for a vehicle according to the second example form performs a shift operation as follows.

Referring to fig. 4, when the engine clutch ECL is operated, six forward speeds are achieved by the same operation of the clutch and the brake because the torque of the motor/generator MG is only an assist torque that drives the vehicle and does not affect the shifting operation of the power transmission device.

In the electric vehicle mode EV, the torque of the motor/generator MG is used to drive the vehicle and does not affect the speed change operation of the power transmission device. Thus, six forward speeds are achieved by the same operation of the clutches and brakes.

Although the transmission according to the first form is incapable of achieving reverse, the motor/generator MG may be controlled to rotate in opposite directions among six forward speeds so as to achieve a reverse speed, as in the case where the motor/generator MG is applied in the second form.

Fig. 5 is a schematic diagram of a power transmission apparatus for a vehicle according to a third example form of the disclosure.

Referring to fig. 5, the third exemplary form differs from the second exemplary form in that: although the motor/generator MG IS employed as the auxiliary power source, the motor/generator MG IS arranged in parallel with the first input shaft IS1, the second input shaft IS2, and the third input shaft IS3, unlike the second exemplary form in which the motor/generator MG IS arranged coaxially with the first input shaft IS1, the second input shaft IS2, and the third input shaft IS 3.

To apply torque from the motor/generator MG, the power transmission device further includes a motor drive gear MDG, a motor driven gear MPG, and an idler gear IDG disposed between the motor drive gear MDG and the motor driven gear MPG. The motor driven gear MPG is selectively connected to an engine output shaft EOS interposed in the engine clutch ECL.

The motor driven gear MPG IS fixedly connected with the first input shaft IS1, and IS selectively connected with the second input shaft IS2 and the third input shaft IS3 interposing the third clutch CL3 and the first clutch CL 1.

It will be clear from this configuration that the vehicle may alternatively be driven in a parallel hybrid drive mode or an electric vehicle mode depending on the operation of the engine clutch ECL.

It will be clearly understood that the power transmission device according to the third example form achieves the same speed change stages through the same operations of the clutches and brakes as in the second example form.

Fig. 6 is a schematic diagram of a power transmission apparatus for a vehicle according to a fourth example form of the disclosure.

Referring to fig. 6, the fourth exemplary form differs from the first exemplary form only in the position of the brake BK.

Although the brake BK is disposed between the torque intermediate shaft TMS and the transmission case H in the first example form, the brake BK is disposed between the second intermediate shaft CS2 and the transmission case H.

The power transmission apparatus according to the fourth example form achieves the same speed change stages through the same operations as the clutches and brakes in the first example form, which will be described in detail with reference to fig. 7.

Fig. 7 is a shift operation table of the power transmission apparatus for a vehicle according to the fourth example form of the disclosure, and the power transmission apparatus for a vehicle according to the fourth example form performs a shift operation as follows.

Fig. 7 shows the same operation table as the operation table of the first example form (see fig. 2) except for "forward sixth speed", which means that the power transmission device according to the fourth example form achieves the same speed change stages by operating the same meshing elements as in the first example form except for "forward sixth speed".

As shown in fig. 7, in the forward sixth speed FD6, the third clutch CL3 and the brake BK are operated.

According to the fourth form, the brake BK is operated to stop the second intermediate shaft CS 2. Therefore, since the ring gear R is fixedly connected with the second counter shaft CS2 through the second speed driven gear TPG2 and the counter gear CG, the ring gear R is also stopped and serves as a fixed element.

When the ring gear R is used as a fixed element, torque of the engine ENG is input to the planet carrier PC of the planetary gear set PG by the operation of the third clutch CL 3.

Then, the ring gear R is fixed as compared with the rotational speed input to the carrier PC, and therefore, the planetary gear set PG outputs a rotational speed further increased than that in the forward fifth speed, thus achieving the forward sixth speed FD6 and outputting the shifted torque to the differential DIFF through the sun gear S and the output shaft OS.

As described above, the power transmission apparatus for a vehicle according to the first exemplary form is capable of achieving the shift stages of six forward speeds by applying one planetary gear set and two synchronizers to the dual clutch transmission, and thus can achieve multiple stages with a simpler structure and reduced weight, thus improving mountability and fuel consumption.

The power transmission apparatus for a vehicle according to the second and third example forms further employs one motor/generator than the first example form, and can be driven in an engine drive mode, a parallel hybrid mode, and an electric vehicle mode, thus further improving fuel consumption.

While the disclosure has been described in connection with what is presently considered to be practical exemplary forms, it is to be understood that the disclosure is not limited to the disclosed forms, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the disclosure.