JP2595934Y2 - Multi-stage transmission - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-speed transmission having a main transmission mechanism and an auxiliary transmission mechanism, and more particularly, to a plurality of main clutches for releasably connecting an engine and an auxiliary transmission. And a multi-stage transmission having a structure arranged in parallel.

[0002]

2. Description of the Related Art In a vehicle, in order to efficiently transmit an engine output to a vehicle body (wheels), a transmission is required to have a plurality of gears. However, if the number of gears is increased with the current structure, the transmission becomes larger and heavier, and the vehicle body becomes larger, the weight increases, and the efficiency decreases. For this reason, conventionally, it has been required to reduce the size and weight of the transmission and to increase the number of gear stages.

[0003] In view of the above, for example, Japanese Utility Model Application
No. 4,375,752 discloses that an engine is connected to a first planetary gear type transmission mechanism (a first auxiliary transmission mechanism) via a main clutch so as to be freely disengageable, and an output shaft of the first planetary gear type transmission mechanism is connected to a first shaft. It is connected to a counter shaft type transmission mechanism (first main transmission mechanism), and further connected to the engine is a second planetary gear type transmission mechanism (second sub transmission mechanism), and an output shaft of the second planetary gear type transmission mechanism. Is connected to a second countershaft type transmission mechanism (second main transmission mechanism).

In Japanese Utility Model Laid-Open Publication No. Sho 61-150228, two main clutches are mounted in parallel on the output shaft of an engine, and the first main clutch is removably connected to the engine output shaft via one clutch. A shaft, a second main shaft removably connected to the engine output shaft via the other clutch, and one counter shaft;
Between the main shaft and the counter shaft and the second
A multi-stage transmission in which a counter shaft type speed change mechanism is disposed between a main shaft and a counter shaft is disclosed.

[0005]

[Problem to be solved by the present invention]
The multi-stage transmission disclosed in Japanese Patent Application Publication No. 752 discloses a multi-stage transmission in which two sets of transmission mechanisms each having a planetary gear type transmission mechanism and a counter shaft type transmission mechanism connected in series are arranged in the axial direction. It is intended to make it. For this reason, it is inevitable that the length of the transmission in the axial direction becomes long, and the problem of increasing the size and weight of the transmission remains even though the number of stages can be increased. Further, in this transmission, in addition to the main clutch, a transmission clutch and a brake of the planetary gear type transmission mechanism are required, and a transmission clutch of the counter shaft type transmission mechanism is also required. There is also a problem that the mechanism is complicated.

On the other hand, in the case of the multi-stage transmission disclosed in Japanese Utility Model Laid-Open Publication No. Sho 61-150228, the first and second main shafts and the counter shaft are disposed in parallel with each other, and the first main shaft and the counter shaft are arranged in parallel. A speed change mechanism provided between the first main shaft and the counter shaft and a speed change mechanism provided between the first main shaft and the counter shaft,
Since the transmission is arranged in parallel in a direction perpendicular to the shaft, the axial dimension of the transmission can be reduced. However, the size in the direction perpendicular to the axis, that is, the width and height of the transmission becomes large, and in this case, there is a problem that the transmission becomes large and heavy.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and it is possible to reduce the size and weight of the transmission as much as possible and to realize a multi-stage transmission having a configuration capable of increasing the number of gear stages. The purpose is to provide.

[0008]

In order to achieve such an object, the transmission according to the present invention has a flywheel housing connected to an end face of a flywheel connected to an end of an engine output shaft so as to cover the end face. The transmission input shaft of the main transmission mechanism protrudes into a space surrounded by these, and a plurality of main clutches (for example, a pair of main clutches) are arranged in parallel in this space. A speed reduction mechanism is also arranged in the inside. Then, an operation of directly engaging and disengaging the flywheel housing and the transmission input shaft by one of the main clutches is performed. Also, the reduction mechanism
It comprises a planetary gear train consisting of a ring gear connected to another main clutch, a carrier connected to the transmission input shaft, and a fixedly held sun gear. Perform the operation to disengage. In this case, the flywheel housing and the ring gear are engaged and disengaged by one main clutch so that the flywheel housing and the transmission input shaft are engaged and disengaged via a speed reduction mechanism, and the flywheel housing is engaged by the other main clutch. And the carrier are disengaged, and the flywheel housing and the transmission input shaft are preferably disengaged via the carrier.

In the multi-stage transmission having such a configuration, a plurality of main clutches are arranged in a space located at the end of the engine output shaft and surrounded by the flywheel and the flywheel housing that are integrally connected. However, one of the main clutches is used to directly engage and disengage the engine output shaft and the transmission input shaft, and the other main clutch is connected to the engine output shaft via a planetary gear type reduction mechanism. An operation for engaging and disengaging the transmission input shaft is performed. For this reason, all the main clutches arranged in parallel in the space engage and disengage the engine flywheel and the transmission input shaft. By selecting engagement of the main clutch, the engine The output can be transmitted directly to the transmission input shaft, or can be decelerated and transmitted to the transmission input shaft via a reduction mechanism. That is, a sub-transmission mechanism can be constituted by a plurality of main clutches and a speed reduction mechanism disposed in the space, whereby the transmission of the engine rotation to one transmission input shaft projecting into the space can be performed. Can be selectively performed using a plurality of reduction ratios. As described above, since the plurality of main clutches not only perform the operation of engaging and disengaging the power transmission but also control the operation of the subtransmission mechanism, it is not necessary to separately provide a clutch for the subtransmission mechanism in addition to the conventional main clutch. Further, by configuring the speed reduction mechanism from the planetary gear train as described above, it is possible to dispose the transmission in a compact manner in the above-mentioned space, and the overall configuration of the transmission can be reduced in size and size. Furthermore, since the engine flywheel and the entire flywheel housing connected thereto act as a flywheel mass (inertia mass) of the engine, there is an advantage that the flywheel size as an engine component can be reduced. In the case where the flywheel housing and the ring gear are engaged and disengaged by one main clutch, and the flywheel housing and the carrier are engaged and disengaged by the other main clutch, the carrier (directly connected plate shown in the embodiment) Since it is a common connecting member with the transmission input shaft, the configuration of the connecting portion with the transmission input shaft is further simplified.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 2 shows a transmission according to an example of the present invention.
The power transmission path of this transmission is configured as shown in FIG. The configuration of this transmission will be described with reference to these drawings. This transmission is directly connected to the engine flywheel 2, and a front end portion of the transmission is covered by a flywheel housing 3, and the flywheel housing 3 has a flywheel 2.
Are combined. The flywheel 2 is connected to an output shaft (crankshaft) 1 of the engine by mounting bolts 1a.

A pump drive gear 4 is formed at the rear end of the flywheel housing 3. The pump drive gear 4 is rotatably supported by a transmission housing 7 and is connected to a pump driven gear 5 connected to a hydraulic pump 6. Are engaged. Therefore, during operation of the engine, the pump drive gear 4 is constantly driven by the engine output shaft 1.
And the hydraulic pump 6 is constantly driven via the pump driven gear 5.

The structure inside the flywheel housing 3 is shown in detail in FIG. 3, and the structure of this portion will be described with reference to this figure. In the flywheel housing 3, first and second main clutches 10 and 15 are arranged in the axial direction. A subtransmission mechanism 20 is disposed radially inward of the main clutches 10 and 15, and a main shaft 31 of the main transmission mechanism 30 is connected to the subtransmission mechanism 20. The auxiliary transmission mechanism 20 includes a clutch plate 11 of the first main clutch 10 and a main shaft 3 of the main transmission mechanism 30.
1 and a planetary gear type speed reduction mechanism 23 that connects the clutch plate 16 of the second main clutch 15 and the main shaft 31 of the main transmission mechanism 30 via the direct connection plate 21. For this reason,
The direct connection plate 21 forms a first power transmission path, and the planetary gear type speed reduction mechanism 23 forms a second power transmission path.

The first main clutch 10 includes a piston 12
The piston 12 is actuated in the engaging direction by receiving the operating oil pressure supplied to the operating oil chamber 13. The hydraulic oil chamber 13 communicates with the transmission housing 7 via oil passages 13a, 13b, 13c, and 13d. The oil passage 13d communicates with a clutch control valve (not shown), and the working oil pressure from the clutch control valve is supplied to the working oil chamber 13 as appropriate via the oil passages 13a to 13d. A back pressure oil chamber 14 is provided opposite to the hydraulic oil chamber 13 via the piston 12.
a, 14b, 14c, and 14d are connected to the transmission housing 7 side. Hydraulic oil having a low operating oil pressure (for example, lubricating oil pressure) is constantly supplied to the oil passage 14d.
Due to the internal spring force, it is always pushed in the release direction.

The second main clutch 15 has a piston 17
, And the piston 17 is operated in the engagement direction by receiving a hydraulic pressure selectively supplied to the hydraulic oil chamber 19. Hydraulic oil chamber 19
Communicates with an oil passage (not shown, formed in parallel with the oil passage 13d) formed in the transmission housing 7 via an oil passage 19a. The oil passage communicates with a clutch control valve (not shown), and the working oil pressure from the clutch control valve is supplied to the working oil chamber 19 via the oil passage 19a as appropriate. The hydraulic oil chamber 19 is provided with a back pressure oil chamber 18 which is opposed to the hydraulic oil chamber 19 via a piston 17. The back pressure oil chamber 18 communicates with the oil passage 14d via an oil passage 18a. Therefore, hydraulic oil having a low operating oil pressure (for example, lubricating oil pressure) is constantly supplied to the back pressure oil chamber 18, and the piston 17 is constantly released by receiving the low pressure oil pressure and the spring force in the back pressure oil chamber 18. It is pushed in the direction.

Here, the oil passage 13 is connected to the clutch control valve.
When the operating oil is supplied to the operating oil chamber 13 through a to 13d, the piston 12 of the first main clutch 10 is pressed in the engaging direction against the pressing force from the back pressure oil chamber 14, and the first main clutch 10 10 are engaged. At this time, the piston 17 of the second main clutch 15 is pressed in the release direction by receiving the pressing force from the back pressure oil chamber 18, and the second main clutch 15 is in a released state. On the other hand, the hydraulic oil chamber 19 from the clutch control valve via the oil passage 19a
When the operating oil is supplied to the second main clutch 15, the piston 17 of the second main clutch 15 is pressed in the engaging direction against the pressing force from the back pressure oil chamber 18, and the second main clutch 17 is engaged. Since the low-pressure hydraulic oil is always supplied to the two back-pressure oil chambers 14 and 18, the centrifugal hydraulic pressure generated in the hydraulic oil chambers 13 and 19 when the clutches 10 and 15 are rotated is reduced. The centrifugal oil pressure generated in the pressure oil chambers 14 and 18 cancels out and cancels out.

The direct connection plate 21 constituting the first power transmission path is a member on a disk, which is spline-engaged with the clutch plate 11 of the first main clutch 10 on the outer diameter side and the main transmission mechanism 30 of the main transmission mechanism 30 on the inner diameter side. Shaft 3
1 is spline-engaged with the tip 31a. The planetary gear type speed reduction mechanism 23 constituting the second power transmission path includes a ring gear 24 that is spline-engaged with the clutch plate 16 of the second main clutch 15 on the outer diameter side, a pinion 25 that meshes with the ring gear 24, The transmission 25 includes a carrier 26 that rotatably supports the carrier 25 and a sun gear 27 that meshes with the pinion 25 and is fixed to the transmission housing 7. The carrier 26 is connected to the direct connection plate 21, and as a result, the carrier 26 is connected to the main shaft 31 of the main transmission mechanism 30. Therefore, the second main clutch 15 is engaged and the ring gear 2
When the motor 7 is driven at the same rotation as the engine output shaft 1, the carrier 26 is driven to rotate at a reduced speed, and the rotation of the carrier 26 is transmitted to the main shaft 31.

Therefore, when the first main clutch 10 is engaged, the engine output from the engine output shaft 1 is transmitted to the main transmission mechanism 30 as it is via the direct connection plate 21, that is, the first power transmission path. 2 main clutch 1
5 is engaged, the engine output is reduced through the planetary gear type reduction mechanism 23, that is, the second power transmission path, and transmitted to the main transmission mechanism 30. Thus, in the transmission of the present embodiment, the first and second main clutches 10, 15
By selectively operating the main clutch, not only the engagement and disengagement control between the engine and the transmission, which is the role of the conventional main clutch,
The operation control of the auxiliary transmission mechanism 20 can be performed at the same time, and the HL speed change of the auxiliary transmission can be performed by this operation control. Specifically, the H shift stage (high speed stage) can be set by engaging the first main clutch 10, and the L shift stage (low speed stage) can be set by engaging the second main clutch 15.

The main transmission mechanism 30 has a main shaft 31 connected to the sub transmission mechanism 20 and a counter shaft 34 disposed in parallel with the main transmission mechanism 20 as described above. It is rotatably supported by 32b and 35a, 35b. On the main shaft 31, a first speed drive gear 41a is rotatably disposed, and second speed, third speed and reverse drive gears 42a, 43a, 44a are fixedly provided. The first-speed drive gear 41a is connected to the main shaft 31 via a first-speed clutch 45.
Is engaged, the first speed drive gear 41a can be connected to the main shaft 31.

On the other hand, the counter shaft 34 has a first speed driven gear 41b and a reverse driven gear 44b.
Are fixed, and the second and third speed driven gears 42b, 43
b is rotatably arranged. However, the second-speed and third-speed driven gears 42b and 43b correspond to the second-speed and third-speed driven gears, respectively.
The speed clutches 46 and 47 can be connected to the counter shaft 34.

The first to third speed driven gears 41b, 4b
2b and 43b are first to third speed drive gears 41, respectively.
a, 42a, 43a, and by selectively operating the first to third speed clutches 45, 46, 47,
The rotation of the main shaft 31 can be transmitted to the counter shaft 34 by changing the speed according to each gear ratio. The reverse driven gear 44b meshes with the reverse drive gear 44a via a rotatable reverse idler gear 44c. This reverse idler gear 44
c is slidable in the axial direction as indicated by arrow A in FIG.
a, 44b and the gears 44a, 4b.
4b and can be moved between the release position and the release position. Therefore, if the reverse idler gear 44c is positioned at the meshing position, a reverse gear for transmitting power via these gears 44a, 44b, 44c can be set.

An output drive gear 38 is also fixedly mounted on the countershaft 34, and this gear 38 meshes with an output driven gear 50 having a differential mechanism 52. The differential mechanism 52 includes left and right axle shafts 5.
4, 55, the rotation of the counter shaft 34 is controlled by the output gear sets 38, 50 and the differential mechanism 52.
Through the axle shafts 54 and 55.

In the transmission having the above-described structure, only by controlling the operation of the first and second main clutches 10 and 15, not only the control of engagement and disengagement between the engine and the transmission (ie, clutch control), but also the control of the auxiliary Operation control of the transmission mechanism can be performed. In addition to this, if the operation control of the main transmission mechanism is performed, the forward six speeds (H-1, 2, 3, and L-1, 2, 2, 3) are set.
3) and the second reverse speed (HR and LR) can be selected. Therefore, in the case of this transmission,
Clutch control and shift control are simple and easy.

Conventionally, in order to achieve the six forward speeds, one main clutch, six sets of gear trains (power transmission paths) and six shift clutches (or brakes) are required. did. However, in the case of the transmission of this embodiment, only the two main clutches and the auxiliary transmission mechanism integrally combined therewith, three sets of gear trains, and three shift clutches are required. It is possible to reduce the size and weight of the machine and increase the number of gears. Further, in the case of this transmission, the sub-transmission mechanism can be disposed radially inward of the main clutch. Therefore, if there is a space in which approximately two sets of main clutches are disposed,
Main clutch and sub-transmission mechanism can be provided,
The transmission can be reduced in size and weight. Note that the flywheel housing 3 covering these components is a flywheel 2
The flywheel housing 3 acts as a flywheel mass. For this reason, the flywheel 2 can be reduced in size, and the axial dimension of the transmission can be reduced accordingly.

In the above description, a counter shaft type speed change mechanism is used as the main speed change mechanism. However, the main speed change mechanism is not limited to this, and a planetary gear type speed change mechanism may be used as the main speed change mechanism. . Further, in this example, a wet multi-plate hydraulic clutch is used as the speed change clutch of the main speed change mechanism, but the present invention is not limited to this. For example, a synchromesh type clutch or a simple dog tooth clutch may be used. The good is of course.

[0025]

[Effects of the Invention] As described above, according to the present invention,
By selectively engaging the plurality of main clutches, the engine output can be directly transmitted to the transmission input shaft, or the engine output can be decelerated via the reduction mechanism and transmitted to the transmission input shaft. The sub-transmission mechanism can be constituted by a plurality of main clutches and a speed reduction mechanism disposed in a space surrounded by the wheel and the flywheel housing. Transmission of engine rotation to the transmission input shaft
This can be selectively performed at a plurality of reduction ratios. As described above, since the plurality of main clutches not only perform the operation of engaging and disengaging the power transmission but also control the operation of the auxiliary transmission mechanism, it is not necessary to separately provide a clutch for the auxiliary transmission mechanism. In addition, the auxiliary transmission mechanism can be disposed compactly. Furthermore, by forming the speed reduction mechanism from the planetary gear train as described above, it can be disposed compactly in the space, and the overall structure of the transmission can be reduced in size.
Can be made compact. In addition, the entire engine flywheel and its associated flywheel housing
Since it acts as a flywheel mass (inertial mass) of the engine, there is also an advantage that the flywheel size as an engine component can be reduced. In the case where the flywheel housing and the ring gear are engaged and disengaged by one main clutch, and the flywheel housing and the carrier are engaged and disengaged by the other main clutch, the carrier (directly connected plate shown in the embodiment) Since it is a common connecting member with the transmission input shaft, the configuration of the connecting portion with the transmission input shaft is further simplified.

[Brief description of the drawings]

FIG. 1 is a skeleton diagram showing a power transmission path of a multi-stage transmission according to the present invention.

FIG. 2 is a sectional view showing a configuration of the multi-stage transmission.

FIG. 3 is a cross-sectional view showing a portion surrounded by a flywheel housing in the multi-stage transmission.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine output shaft 2 Flywheel 3 Flywheel housing 10, 15 Main clutch 20 Subtransmission mechanism 23 Planetary gear type reduction mechanism 30 Main transmission mechanism 31 Main shaft 34 Counter shaft

Claims (2)

(57) [Scope of request for utility model registration] A flywheel coupled to an end of an engine output shaft; a flywheel housing covering an end face of the flywheel and coupled to the flywheel; and being surrounded by the flywheel and the flywheel housing. A main transmission mechanism having a transmission input shaft protruding into a closed space; a plurality of main clutches disposed in parallel in a space surrounded by the flywheel and the flywheel housing; and the flywheel. A speed reduction mechanism disposed in a space surrounded by the flywheel housing, and any one of the main clutches performs an operation of directly engaging and disengaging the flywheel housing and the transmission input shaft, The speed reduction mechanism is connected to a ring gear connected to the other main clutch and the transmission input shaft. A multi-stage transmission comprising a planetary gear train including a carrier and a fixedly held sun gear, wherein the other main clutch performs an operation of engaging and disengaging the flywheel housing and the ring gear. 2. The main clutch according to claim 1, wherein the plurality of main clutches include a pair of main clutches arranged in parallel in the axial direction in a space surrounded by the flywheel and the flywheel housing. Engages and disengages the flywheel housing and the ring gear, and engages and disengages the flywheel housing and the transmission input shaft via the speed reduction mechanism. The other main clutch includes the flywheel housing and the carrier. 2. The multi-stage transmission according to claim 1, wherein the flywheel housing is disengaged from the transmission input shaft via the carrier. 3.