KR101755816B1

KR101755816B1 - Transmission for vehicles

Info

Publication number: KR101755816B1
Application number: KR1020150106025A
Authority: KR
Inventors: 권여현; 손충완; 조창연; 이병현; 박기종
Original assignee: 현대자동차주식회사
Priority date: 2015-07-27
Filing date: 2015-07-27
Publication date: 2017-07-10
Also published as: KR20170013476A

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a transmission for a vehicle that minimizes the overall length of a transmission and provides a multiple-speed transmission.
To this end, the present invention includes a first output shaft and a second output shaft arranged in parallel to a first input shaft and a second input shaft, A plurality of gear pairs having gear ratios different from each other are coupled to the first input shaft and the second input shaft, the first output shaft and the second output shaft, and a gear pair matching the running speed is selected by the synchronizing device, A transmission unit for outputting the output; A reverse gear provided on the first output shaft or the second output shaft and meshed with an output gear paired with the input gear provided on the first input shaft; And a transfer synchronizing device for selectively coupling the reverse gear and the output gear paired with the input gear provided on the second input shaft, wherein the gear ratio of the gear pair realized by the combination of the transfer synchronizing device, A vehicle transmission is introduced which combines a gear ratio of a gear pair selected by an apparatus to implement a reverse gear ratio.

Description

[0001] TRANSMISSION FOR VEHICLES [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to a transmission for a vehicle, and more particularly, to a transmission for a vehicle that minimizes the overall length of the transmission and provides multiple transmissions.

In order to respond to high oil prices and CO ₂ environment regulations, it is necessary to improve the fuel efficiency of the vehicle more. Recently, environmental vehicles with reduced fuel consumption, such as electric vehicles and hybrid vehicles, have been continuously studied and developed In fact there is.

However, in the case of an electric vehicle, there is a problem that the price of a battery or a motor, which is a core part necessary for driving the vehicle, is very high, which is higher than that of a general vehicle using fossil fuel. There is a problem that diffusion is not universal.

An automatic manual transmission based on a synchronous manual transmission mechanism automatically shifts by an actuator during operation of the vehicle, so it provides driving convenience similar to that of an automatic transmission, It can contribute to improvement.

Particularly, the DCT can prevent shift phenomenon caused by disconnection of power of the engine by executing the shift through the handover control that cross-controls the two clutches during shifting of the gear.

However, in the case of DCT, it is also necessary to reduce the number of transmission shafts in order to further improve the fuel economy and commerciality of the vehicle, and also to minimize the total length of the transmission in order to improve the mountability of the multi-shafted transmission.

It should be understood that the foregoing description of the background art is merely for the purpose of promoting an understanding of the background of the present invention and is not to be construed as an admission that the prior art is known to those skilled in the art.

KR 10-2008-0033700 A

Disclosure of Invention Technical Problem [8] The present invention has been made to solve the conventional problems as described above, and it is an object of the present invention to provide a vehicular transmission that minimizes the overall length of the transmission and provides multiple transmissions.

According to an aspect of the present invention, there is provided an electronic apparatus comprising: a first output shaft and a second output shaft disposed in parallel with a first input shaft and a second input shaft; A plurality of gear pairs having gear ratios different from each other are coupled to the first input shaft and the second input shaft, the first output shaft and the second output shaft, and a gear pair matching the running speed is selected by the synchronizing device, A transmission unit for outputting the output; A reverse gear provided on the first output shaft or the second output shaft and meshed with an output gear paired with the input gear provided on the first input shaft; And a transfer synchronizing device for selectively coupling the reverse gear and the output gear paired with the input gear provided on the second input shaft, wherein the gear ratio of the gear pair realized by the combination of the transfer synchronizing device, The reverse gear ratio can be realized by combining the gear ratios of the gear pairs selected by the device.

The reverse gear is provided on a second output shaft; An output gear engaged with the reverse gear is provided on a first output shaft; The transfer synchronization device may selectively couple the reverse gear provided on the second output shaft and the output gear provided on the second output shaft.

The transfer synchronizing device may be fixed to an output gear selectively coupled to the reverse gear or the reverse gear.

The reverse gear is meshed with an output gear of a gear pair having the largest gear ratio among gear pairs provided in the transmission portion; The transfer synchronizing device is provided in the transmission unit and can couple the output gear of the gear pair having the smallest gear ratio among the pair of gears forming the even means to the reverse gear.

Wherein the first input shaft, the first output shaft, and the second output shaft are coupled to a plurality of input gears and output gears, respectively, which form a hole means; The second input shaft, the first output shaft, and the second output shaft may be coupled to each other by a plurality of input gears and output gears forming an equivalent means.

The two gear pairs for forming the hole means share one input gear; And the two gear pairs for forming the even-numbered means share one input gear.

A pair of gears for forming first, third and fifth stages of the first input shaft and the first output shaft are engaged with each other; The first input shaft and the second output shaft are meshed with gear pairs for forming seven stages; A gear pair for forming two-stage and six-stage gears is engaged with the second input shaft and the first output shaft; A gear pair for forming four stages and eight stages is meshed with the second input shaft and the second output shaft; The gear pair for the 5-step formation and the gear pair for the 7-step formation share the input gear; The gear pair for the six-step formation and the gear pair for the eight-step formation may share the input gear.

A pair of gears for forming first, third, and seventh stages is engaged with the first input shaft and the first output shaft; A gear pair for forming a five-stage, nine-stage gear is mated with the first input shaft and the second output shaft; A gear pair for forming two-stage and six-stage gears is engaged with the second input shaft and the first output shaft; A gear pair for forming four stages and eight stages is meshed with the second input shaft and the second output shaft; The gear pair for the three-step formation and the gear pair for the five-step formation share an input gear; A gear pair for forming the 7th step and a gear pair for forming the 9th step share an input gear; The gear pair for the six-step formation and the gear pair for the eight-step formation may share the input gear.

A pair of gears for forming first, third, and seventh stages is engaged with the first input shaft and the first output shaft; A gear pair for forming a five-stage, nine-stage gear is mated with the first input shaft and the second output shaft; A pair of gears for forming the second, fourth, and eighth stages are meshed with the second input shaft and the first output shaft; A gear pair for forming six stages and ten stages is meshed with the second input shaft and the second output shaft; The gear pair for the three-step formation and the gear pair for the five-step formation share an input gear; A gear pair for forming the 7th step and a gear pair for forming the 9th step share an input gear; The gear pair for forming the 8-step and the gear pair for forming the 10-step may share an input gear.

The present invention has the effect of reducing the cost and weight of the transmission by realizing the multi-shoe of the transmission while reducing the number of components required for shifting, In the case of some gear pairs, the input gear is used in common with other gear pairs, thereby reducing the space required for the input gear arrangement, thereby reducing the overall length of the transmission.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing a layout of a forward 8-speed transmission according to the present invention and a power transmission path at a time of backward movement. Fig.
Fig. 2 is a shift operation table of the transmission shown in Fig. 1. Fig.
3 is a view showing a layout of a forward 9th speed transmission according to the present invention and a power transmission path at a time of backward movement.
4 is a shift operation table of the transmission shown in Fig.
5 is a view showing a layout of a forward 10-speed transmission according to the present invention and a power transmission path at the time of backward movement.
6 is a shift operation table of the transmission shown in Fig.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The transmission for a vehicle of the present invention includes a first input shaft INPUT1 and a second input shaft INPUT2, a first output shaft OUTPUT1 and a second output shaft OUTPUT2, a transmission unit 3, a reverse gear GR ) And a transfer synchronization device (ST).

1, the first input shaft INPUT1 selectively receives the power of the engine 1 via a first clutch C1, the second input shaft INPUT2 receives a second The power of the engine 1 can be selectively input via the clutch C2.

For example, the second input shaft INPUT2 may be formed as a hollow shaft, and the first input shaft INPUT1 may be coaxially inserted into the second input shaft INPUT2.

The first output shaft OUTPUT1 is disposed in parallel to the first input shaft INPUT1 and the second input shaft INPUT2 and the second output shaft OUTPUT2 is disposed in parallel with the first input shaft INPUT1 and the second input shaft INPUT2 .

The transmission unit 3 has a first input shaft INPUT1 and a second input shaft INPUT2 coupled to a first output shaft OUTPUT1 and a second output shaft OUTPUT2 by a plurality of gear pairs having different gear ratios , It is possible to select the gear pair matching the running speed by the synchronizing device and to output the power of the driving source, that is, the engine 1, by shifting.

The reverse gear GR can be provided on the first output shaft OUTPUT1 or the second output shaft OUTPUT2 and can be engaged with an output gear paired with any one of the input gears provided on the first input shaft INPUT1 have.

For example, the reverse gear GR may be provided on the second output shaft OUTPUT2, and the output gear meshed with the reverse gear GR may be provided on the first output shaft OUTPUT1.

At this time, the reverse gear (GR) can be engaged with an output gear of a gear pair having the largest gear ratio among gear pairs provided in the transmission unit (3). For example, the reverse gear GR may be engaged with an output gear of a gear pair for one-step forming.

The transfer synchronizer ST can selectively couple the reverse gear GR and the output gear paired with the input gear provided on the second input shaft INPUT2 to each other.

For example, the transfer synchronization device ST can selectively couple the reverse gear GR provided on the second output shaft OUTPUT2 and the output gear provided on the second output shaft OUTPUT2.

Further, the transfer synchronizing device ST may be fixed to the output gear selectively coupled to the reverse gear GR or the reverse gear GR. That is, the transfer synchronizing device ST can be fixed to the reverse gear GR and moved and coupled to the output gear on one side thereof, or can be fixed to the output gear and moved and coupled to the reverse gear GR have.

The transfer synchronizer ST may be provided in the transmission unit 3 to couple the output gear of the gear pair having the smallest gear ratio among the gear pairs forming the even unit to the reverse gear GR.

1 and 3, the transfer synchronizing device ST can couple the reverse gear GR and the output gear of the 8th gear pair, and in the case of FIG. 5, the reverse gear GR and the 10th gear The output gear of the gear pair can be coupled.

In the coupling operation of the transfer synchronizing apparatus ST, the gear ratio of the reverse gear GR coupled with the transfer synchronizer ST is combined with the gear ratio of the gear pair selected by the synchronizer, Gear ratio can be implemented.

That is, as shown in FIGS. 1, 3, and 5, the transmission unit 3 is provided with a pair of gears having one to eight gears, one to nine gears, one to ten gears, Even if there is no input gear paired with the reverse idler shaft and the reverse gear GR for the post-diagnosis implementation, the reverse gear ratio can be realized through the combination of the transfer synchronizer ST and the synchronizer.

According to such a configuration, the present invention realizes the post-diagnosis while reducing the number of gears and shafts required for the reverse shift, thereby reducing the cost and weight of the transmission.

In the present invention, a plurality of input gears and output gears for forming the first input shaft INPUT1 and the first output shaft OUTPUT1 and the first input shaft INPUT1 and the second output shaft OUTPUT2, Can be combined.

A plurality of input gears and output gears forming an equivalent means to the second input shaft INPUT2 and the first output shaft OUTPUT1 and the second input shaft INPUT2 and the second output shaft OUTPUT2 can be engaged with each other have.

Particularly, the present invention can be configured such that two gear pairs for forming the hole means share one input gear, and two gear pairs for forming an even number means can share one input gear.

For example, referring to FIG. 1, gear pairs for forming first, third, and fifth gears may be meshingly coupled to the first input shaft INPUT1 and the first output shaft OUTPUT1. The first input shaft INPUT1, And the second output shaft OUTPUT2 may be meshed with gear pairs for forming seven stages.

The second input shaft INPUT2 and the first output shaft OUTPUT1 may be provided with gear pairs for forming two-stage and six-stage gears. The second input shaft INPUT2 and the second output shaft OUTPUT2 may be provided with four However, a pair of gears for forming eight stages may be provided.

At this time, the gear pair for forming the five-step and the gear pair for forming the seventh step may be configured to share the input gear, and the gear pair for forming the six-step and the gear pair for forming the eight- Can be shared.

That is, the 5th & 7th stage input gears GI5 & 7 for forming the fifth and seventh stages are coupled to the fifth stage output gear GO5 and the seventh stage output gear GO7, respectively, And the gears GI6 & 8 can be engaged with the six-stage output gear GO6 and the eight-stage output gear GO8, respectively.

In such a structure, the transfer synchronizer ST may be configured to selectively couple the output gear for forming the eighth stage with the reverse gear GR, and the reverse gear GR or the eighth-stage output gear GO8 So as to rotate together.

The first output shaft OUTPUT1 may be provided with a two-stage synchronous device S2 at one side of the two-stage output gear GO2 and may be provided at a position between the first output gear GO1 and the sixth- Stage synchronizers S3 & 5 may be arranged between the third-stage output gear G3O and the fifth-stage output gear GO5.

A 4 & 8 stage synchronizing device S4 & 8 can be arranged between the 4th stage output gear GO4 and the 8th stage output gear GO8 in the second output shaft OUTPUT2, A synchronizing device S7 may be arranged. A parking gear may be disposed on the side of the four-stage output gear GO4.

Referring to FIG. 3, a gear pair for forming one, three, or seven stages may be meshed with the first input shaft INPUT1 and the first output shaft OUTPUT1, INPUT1 and the second output shaft OUTPUT2 may be meshed with a pair of gears for forming five stages and nine stages.

At this time, the gear pair for the three-step formation and the gear pair for the five-step formation can be configured to share the input gear, and the gear pair for forming the seventh step and the gear pair for forming the nine- And the gear pair for forming the six-step and the gear pair for forming the eight-step may be configured to share the input gear.

That is, the third and fifth stage input gears GI3 & 5 for forming the third and fifth stages are coupled to the third stage output gear GO3 and the fifth stage output gear GO5 respectively, and 7 & 9 stage inputs The gears GI7 and GI9 are engaged with the seventh output gear GO7 and the nine stage output gear GO9 respectively and the sixth and eighth stage input gears GI6 and 8 for forming the sixth and eighth stages are meshed with the sixth stage output gear GO6 Stage output gear GO8, respectively.

The first output shaft OUTPUT1 may be provided with a two-stage synchronous device S2 at one side of the two-stage output gear GO2 and may be provided at a position between the first output gear GO1 and the sixth- Stage synchronizers S3 & 7 may be disposed between the third-stage output gear G3O and the seventh-stage output gear GO7.

A 4 & 8 stage synchronizing device S4 & 8 can be disposed between the 4th stage output gear GO4 and the 8th stage output gear GO8 in the second output shaft OUTPUT2, and the 5th stage output gear GO5 and 9th stage output 5 & 9 stage synchronizers S5 & 9 may be disposed between the gears G09. A parking gear may be disposed on the side of the four-stage output gear GO4.

5, a pair of gears for forming first, third and seventh gears may be engaged with the first input shaft INPUT1 and the first output shaft OUTPUT1, A gear pair for forming the fifth and ninth stages may be engaged with the first output shaft INPUT1 and the second output shaft OUTPUT2.

The second input shaft INPUT2 and the first output shaft OUTPUT1 may be provided with gear pairs for forming two-stage, four-stage and eight-stage gears. The second input shaft INPUT2 and the second output shaft OUTPUT2 ), And a pair of gears for forming the tenth and tier stages may be engaged with each other.

At this time, the gear pair for the three-step formation and the gear pair for the five-step formation can be configured to share the input gear, and the gear pair for forming the seventh step and the gear pair for forming the nine- And the gear pair for forming the 8-step and the gear pair for forming the 10-step may be configured to share the input gear.

That is, the third and fifth stage input gears GI3 & 5 for forming the third and fifth stages are coupled to the third stage output gear GO3 and the fifth stage output gear GO5 respectively, and 7 & 9 stage inputs The gears GI7 and GI9 are engaged with the seventh-stage output gear GO7 and the nine-stage output gear GO9 respectively and the 8th and 10th stage input gears GI8 and 10 for forming the 8th and 10th gears are engaged with the 8th- 10 output gears GO10, respectively.

In such a structure, the transfer synchronizer ST may be configured to selectively couple the output gear for forming the 10-stage to the reverse gear GR, and the reverse gear GR or the 10-speed output gear GO8 So as to rotate together.

The first output shaft OUTPUT1 may be provided with a 2 & 4 stage synchronizer S2 & 4 between the second stage output gear GO2 and the fourth stage output gear GO4. The 1 & 8 stage synchronizing apparatuses S1 & 8 may be arranged between the output gears GO8 and 3 & 7th stage synchronizing apparatuses S3 & 7 may be arranged between the 3 stage output gear G3O and the 7th stage output gear GO7.

According to such a configuration, since the input gear is shared with another gear pair in the case of some gear pairs of the gear pair provided in the transmission unit 3, the space required for the input gear arrangement is reduced, The overall length of the transmission can be reduced, and as a result, it is possible to realize the multi-shoe of the transmission while reducing the overall length of the transmission.

Hereinafter, the power transmission flow path in the post-diagnosis according to each transmission structure according to the present invention will be described.

Referring to FIGS. 1 and 3, the reverse gear GR and the 8-speed output gear GO8 are coupled by the transfer synchronizer ST and the 4-speed output gear GO4 is connected by the 4 & 8- The first clutch C1 is engaged.

Then, the power of the engine 1 is transmitted to the first-stage input gear GI1 and the first-stage output gear GO1 via the first input shaft INPUT1, and the reverse gear GR1 meshed with the first- And the eighth-stage output gear GO8 to the sixth & eighth-stage input gears GI6 &

And then transmitted to the second output shaft OUTPUT2 via the fourth input gear GI4 and the fourth output gear GO4 from the second input shaft INPUT2 equipped with the sixth and eighth gears GI6 and 8, It is possible to output the engine 1 power corresponding to the engine speed.

For reference, in the case of the remaining forward-drive stage, as shown in the shift operation charts shown in FIG. 2 and FIG. 4, each gear stage is formed through the engagement of the gear pair for forming the gear stage and the synchronizer .

5, the reverse gear GR and the 10-speed output gear GO10 are coupled by the transfer synchronizer ST and the 6-speed output gear GO6 is selected by the 6 & 10-speed synchronizer S6 & The first clutch C1 is engaged.

Then, the power of the engine 1 is transmitted to the first-stage input gear GI1 and the first-stage output gear GO1 via the first input shaft INPUT1, and the reverse gear GR1 meshed with the first- And the 10th stage output gear GO8 to the 8 & 10th stage input gears GI8 & 10.

Then, from the second input shaft INPUT2 provided with the 8 & 10-speed stage input gears GI6 & 8 to the second output shaft OUTPUT2 via the six-stage input gear GI6 and the six- It is possible to output the engine 1 power corresponding to the engine speed.

For reference, in the case of the remaining forward-drive stage, the respective gearshift stages can be formed by engaging the gear pair and the synchronizing device for forming the gearshift end, as shown in the shift operation chart shown in FIG.

As described above, according to the present invention, the number of components (gears and shafts) necessary for shifting is reduced, and the cost and weight of the transmission are reduced, In the case of some gear pairs of the gear pair, the input gear is used in common with other gear pairs, thereby reducing the space required for the input gear arrangement, thereby reducing the overall length of the transmission.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limited to the specific embodiments set forth herein; rather, .

1: Engine 3: Transmission unit
INPUT1: first input shaft INPUT2: second input shaft
OUTPUT1: first output shaft OUTPUT2: second output shaft
C1: first clutch C2: second clutch
ST: Transfer synchronizer GR: Reverse gear

Claims

A first input shaft and a second input shaft selectively receiving power of a drive source via the first clutch and the second clutch;
A first output shaft and a second output shaft disposed in parallel with the first input shaft and the second input shaft;
A plurality of gear pairs having gear ratios different from each other are coupled to the first input shaft and the second input shaft, the first output shaft and the second output shaft, and a gear pair matching the running speed is selected by the synchronizing device, A transmission unit for outputting the output;
A reverse gear provided on the first output shaft or the second output shaft and meshed with an output gear paired with the input gear provided on the first input shaft; And
And a transfer synchronizing device which couples the reverse gear and the output gear which is paired with the input gear provided on the second input shaft,
A reverse gear ratio is implemented by combining a gear ratio of a gear pair implemented by the combination of the transfer synchronizing device and a gear ratio of a gear pair selected by the synchronizing device,
A pair of gears for forming first, third and fifth stages of the first input shaft and the first output shaft are engaged with each other;
The first input shaft and the second output shaft are meshed with gear pairs for forming seven stages;
A gear pair for forming two-stage and six-stage gears is engaged with the second input shaft and the first output shaft;
A gear pair for forming four stages and eight stages is meshed with the second input shaft and the second output shaft;
The gear pair for the 5-step formation and the gear pair for the 7-step formation share the input gear;
Wherein the gear pair for the six-step formation and the gear pair for the eight-step formation share an input gear.

The method according to claim 1,
The reverse gear is provided on a second output shaft;
An output gear engaged with the reverse gear is provided on a first output shaft;
Wherein the transfer synchronizing device selectively couples the reverse gear provided on the second output shaft and the output gear provided on the second output shaft.

The method according to claim 1,
Wherein the transfer synchronizing device is fixed to the reverse gear or fixed to an output gear provided on the second output shaft.

The method according to claim 1,
The reverse gear is meshed with an output gear of a gear pair having the largest gear ratio among gear pairs provided in the transmission portion;
Wherein the transfer synchronizing device is provided in the transmission portion and couples the output gear of the gear pair having the smallest gear ratio among the gear pairs forming the even means to the reverse gear.

The method according to claim 1,
Wherein the first input shaft, the first output shaft, and the second output shaft are coupled to a plurality of input gears and output gears, respectively, which form a hole means;
Wherein the second input shaft, the first output shaft, and the second output shaft are coupled to each other by a plurality of input gears and output gears forming an equivalent means.

The method of claim 5,
The two gear pairs for forming the hole means share one input gear;
And the two gear pairs for forming the even unit share one input gear.

delete

A first input shaft and a second input shaft selectively receiving power of a drive source via the first clutch and the second clutch;
A first output shaft and a second output shaft disposed in parallel with the first input shaft and the second input shaft;
A plurality of gear pairs having gear ratios different from each other are coupled to the first input shaft and the second input shaft, the first output shaft and the second output shaft, and a gear pair matching the running speed is selected by the synchronizing device, A transmission unit for outputting the output;
A reverse gear provided on the first output shaft or the second output shaft and meshed with an output gear paired with the input gear provided on the first input shaft; And
And a transfer synchronizing device which couples the reverse gear and the output gear that is paired with the input gear provided on the second input shaft,
A reverse gear ratio is implemented by combining a gear ratio of a gear pair implemented by the combination of the transfer synchronizing device and a gear ratio of a gear pair selected by the synchronizing device,
A pair of gears for forming first, third, and seventh stages is engaged with the first input shaft and the first output shaft;
A gear pair for forming a five-stage, nine-stage gear is mated with the first input shaft and the second output shaft;
A gear pair for forming two-stage and six-stage gears is engaged with the second input shaft and the first output shaft;
A gear pair for forming four stages and eight stages is meshed with the second input shaft and the second output shaft;
The gear pair for the three-step formation and the gear pair for the five-step formation share an input gear;
A gear pair for forming the 7th step and a gear pair for forming the 9th step share an input gear;
Wherein the gear pair for the six-step formation and the gear pair for the eight-step formation share an input gear.

A first input shaft and a second input shaft selectively receiving power of a drive source via the first clutch and the second clutch;
A first output shaft and a second output shaft disposed in parallel with the first input shaft and the second input shaft;
A plurality of gear pairs having gear ratios different from each other are coupled to the first input shaft and the second input shaft, the first output shaft and the second output shaft, and a gear pair matching the running speed is selected by the synchronizing device, A transmission unit for outputting the output;
A reverse gear provided on the first output shaft or the second output shaft and meshed with an output gear paired with the input gear provided on the first input shaft; And
And a transfer synchronizing device which couples the reverse gear and the output gear which is paired with the input gear provided on the second input shaft,
A reverse gear ratio is implemented by combining a gear ratio of a gear pair implemented by the combination of the transfer synchronizing device and a gear ratio of a gear pair selected by the synchronizing device,
A pair of gears for forming first, third, and seventh stages is engaged with the first input shaft and the first output shaft;
A gear pair for forming a five-stage, nine-stage gear is mated with the first input shaft and the second output shaft;
A pair of gears for forming the second, fourth, and eighth stages are meshed with the second input shaft and the first output shaft;
A gear pair for forming six stages and ten stages is meshed with the second input shaft and the second output shaft;
The gear pair for the three-step formation and the gear pair for the five-step formation share an input gear;
A gear pair for forming the 7th step and a gear pair for forming the 9th step share an input gear;
Wherein the gear pair for the 8-step formation and the gear pair for the 10-step formation share an input gear.