JPS6326450A - Power transmission device for vehicle - Google Patents

Abstract

PURPOSE:To shorten an axial length of an overall device, by disposing a ring- shaped member radially outwardly of a planetary gear unit and disposing each one of a plurality of brake units and one way clutch units within a width in an axial direction of a gear unit. CONSTITUTION:A torque converter 2 and a multi-stage transmission unit 10 are coaxially disposed on a crank shaft 1. The unit 10 is provided with a planetary gear unit 14, each plurality of clutch units 20, 21, 24, an oneway clutch units 22 and 26 and brake units 23, 25 disposed around the planetary gear unit 14. In the arrangement, a ring-shaped member 26b having a prescribed width in an axial direction 26b is disposed at an outer circumference of a width in an axial direction of the unit 14 and an outer circumference of a carrier 14a is connected to the ring-shaped member 26b. Further, the second brake unit 25 and the one-way clutch unit 26 are disposed between the ring-shaped member 26b and a case in a close relation radially outwardly of the unit 14.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a power transmission device for an automobile, and more particularly to a power transmission device for an automobile equipped with a Ravignault type planetary gear unit.

(Prior Art) As a power transmission device equipped with the above-mentioned Lavigneaux-type planetary gear unit, one disclosed, for example, in Japanese Patent Application Laid-open No. 1848/1983 is known.

In a power transmission device equipped with such a Ravigneaux-type planetary gear unit, a second one-way clutch is used to prevent the carrier from reversing and to adjust the timing of shifting between 1st and 2nd gears. A second braking device is indispensable in order to obtain a brake and to fix the carrier during reverse, respectively;
Therefore, it is necessary to make the structure compact and shorten the axial length.

Therefore, in the power transmission device disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 57-1848, a brake device corresponding to the second brake device is disposed radially outward of the planetary gear unit, thereby reducing the axial length. However, since the one-way clutch corresponding to the second one-way clutch is located on the axial side of the planetary gear unit, the axial length of the automatic transmission is increased in this respect. There is a problem with this.

(Object of the Invention) The present invention provides a power transmission device using the Ravigneaux type planetary gear unit described above, and aims to make the structure more compact and shorten the axial length.

(Structure of the Invention) In order to achieve the above object, the power transmission device of the present invention includes an annular member having a predetermined width in the axial direction disposed on the outer circumference of the Ravigneau type planetary gear unit within the axial width thereof, and , the annular member and the outer periphery of the planetary gear unit are connected to each other, and a second brake device and a second one-way clutch device are arranged adjacent to each other between the annular member and the case of the multi-speed gear device. It is characterized in that it is arranged outward in the radial direction, and more specifically, it is equipped with a torque converter and a multi-speed gear device arranged sequentially from the engine side coaxially with the crankshaft of the engine, and the multi-speed change gear a turbine shaft having a base end connected to the turbine of the torque converter and a distal end extending to a side wall of the multi-speed gearing and rotatably supported by the side wall; a small diameter sun gear provided on the turbine shaft; , a Ravigneaux-type planetary gear unit consisting of a large diameter sun gear, a long pinion gear, a short pinion gear, a carrier for holding both of these pinion gears, and a ring gear, and a second clutch that connects and disconnects power transmission between the small diameter sun gear and the turbine shaft. a first clutch device that engages and disengages the large-diameter sun gear from the case of the multi-speed gear device; a third clutch device that connects and disconnects power transmission between the large-diameter sun gear and the turbine shaft; a second brake device that engages and disengages the carrier of the planetary gear and the case of the nuclear speed change gear device; a fourth clutch device that connects and disconnects power transmission between the carrier of the planetary gear unit and the turbine shaft; a ring gear of the planetary gear unit; In the power transmission device for an automobile having an output gear connected to the Ravigneaux type planetary gear unit, an annular member having a predetermined width in the axial direction is disposed on the outer circumference of the Ravigneau type planetary gear unit within the axial width thereof; , an outer peripheral portion of the carrier is connected to the annular member, the second brake device and the second one-way clutch device are arranged adjacent to each other between the annular member and the case, and the radius of the planetary gear unit is It is characterized by having a configuration in which it is arranged outward in the direction.

(Effects of the Invention) In the automobile power transmission device configured as described above,
An annular member having a predetermined width is disposed radially outward of the Ravigneau type planetary unit and is connected to the outer circumference of the carrier of the unit, and includes a second braking device that is a low reverse brake and a second one-way clutch for first speed. are disposed adjacent to each other between the annular member and the case within the axial width of the Ravigneau type planetary unit, so the axial length of the entire device can be shortened without complicating the structure.

(Embodiments) Hereinafter, a power transmission device for an automobile according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a schematic diagram showing a power transmission device for an automobile according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 indicates the input shaft of the engine (
A torque converter 2 and a multi-speed gear system 10 are arranged coaxially with the crankshaft 1 (not shown) in order from the engine side. The torque converter 2 includes a pump 3, a turbine 4, and a stator 5, and the pump 3 is fixed to the crankshaft 1. The stator 5 rotates via a one-way clutch 6 on a defining shaft 7 that is integral with the case 11 of the multi-speed gear device 10 . The one-way clutch 6 connects the stator 5 to the pump 3.
It allows rotation in the same direction, but does not allow rotation in the opposite direction.

The multi-speed gear device 10 has a base end fixed to the crankshaft l and a distal end extending through the center of the multi-speed gear device to drive an oil pump P disposed on the side wall of the device. It has a solid shaft 12 connected to the pump. On the outside of this solid shaft 12, a hollow shaft is connected at its base end to the turbine 4 of the torque converter 2, and whose distal end extends to the side wall of the multi-speed gear unit 10, and is rotatably supported by the side wall. A turbine shaft 13 is provided. A Ravigneau type planetary gear unit 14 is provided on the turbine shaft 13, and this planetary gear unit 14 includes a small diameter sun gear 15, a large diameter sun gear 16 disposed on the side of the small diameter sun gear 15 far from the engine, It consists of a long pinion gear 17, a short pinion gear 18, and a ring gear 19.

On the side of the planetary gear unit 14 far from the engine are first and second clutch devices 20, 21.
are arranged in parallel. The first clutch device 2
0 is for intermittent power transmission between the small diameter sun gear 15 and the turbine shaft 13 via the first one-way clutch 22. On the other hand, the second clutch device 2
1 is connected in parallel with the first clutch device 20 and connects and disconnects power transmission between the small diameter sun gear 15 and the turbine shaft 13. A first brake device 23 is arranged radially outward of the second clutch device 21 . This first brake device 23 is a handbrake, and has a brake drum 23a connected to the large-diameter sun gear 16 and a brake band 23b applied to the brake drum. radially outward of the first clutch device 2o and the first brake device 23
A third clutch device 24 is disposed on the side of the brake device 24, and the third clutch device 24 connects the large-diameter sun gear 16 and the turbine shaft 13 via the brake drum 23a of the first brake device 23. This is used to cut and break power transmission between the two.

Radially outward of the planetary gear unit 14,
A second brake device 25 is arranged to engage and disengage the carrier 14a of the planetary gear unit 14 and the case 10a of the multi-speed gear device 1o. Between the first and second brake devices 23 and 25, the carrier 14a and the case 10a are arranged in parallel with the second brake device 25.
A second one-way clutch device 26 is arranged to engage and disengage the two. A fourth clutch device 27 is disposed on the engine side side of the planetary gear unit throat 14 to connect and disconnect power transmission between the carrier 14a of the planetary gear unit and the turbine shaft 13. An output gear 28 connected to the ring gear 19 is arranged on the side of the fourth clutch device 27 on the engine side. Reference numeral 29 in the figure indicates a lock amplifier clutch for directly connecting the turbine shaft 13 and the crankshaft 1 without going through the torque converter 2.

Next, with reference to FIG. 2, the structure of each of the above-mentioned devices constituting the present power transmission device will be explained.

The second clutch device 21 includes a clutch drum spline-coupled to the turbine shaft 13 and integrally supported by a support portion 21a having a substantially U-shaped cross section. 21
It is equipped with b. A clutch hub 21c is disposed inside the clutch drum 21b, and the clutch hub 21c is integrally supported by a support portion 21d splined to the small diameter sun gear 15. The clutch drum 21b and the clutch hub 21c each support alternately arranged clutch discs 21e. A piston 21f having a shape corresponding to the contour of the inner wall of the support portion 21 and having a U-shaped cross section is fitted inside the support portion 21a. A hydraulic oil chamber 21g is formed between the piston 21f and the support body 21a, and by controlling the supply of hydraulic oil to this hydraulic oil chamber 21g, the clutch disc 21e is pushed or released. , engages and disengages the second clutch device 21. As is clear from the figure, the base of the support portion 21d of the clutch hub 21c constitutes an inner race of the first one-way clutch 22.

- Clutch device 20 The piston 21f of the second clutch device 21 is connected to the clutch drum 20a of the first clutch device 20 and the support portion 2 that integrally supports the clutch drum 20a.
Also serves as 0b. A clutch hub 20c is arranged inside the clutch drum 20a, and this clutch hub 2
0c has a base portion integrally supported by a support portion 20d that constitutes the outer race of the one-way clutch 22. The clutch drum 20a and the clutch hub 20
Clutch disks 20e arranged alternately
is supported. The piston 2 is located inside the support portion 20b.
0f is fitted, and this piston 2Of and the support part 2
20 g of hydraulic oil chambers are formed between 0b. By controlling the supply of hydraulic oil to the hydraulic oil chamber 20g, the clutch disc 20e is pushed or released, and the first clutch device 20 is engaged or disengaged. In addition, 20h in the figure is the piston 20f of the first and second clutch devices 20.21.

The return spring for 21f is shown.

Third clutch 4"724 This third clutch device 24 includes a clutch drum 24b that is integral with the support section 21a and is integrally supported by a substantially inverted support section 24a. This clutch drum A clutch hub 24c is disposed inside and facing the clutch hub 24b.
4c is the brake drum 23 of the first brake device 23
It is formed by an extension of a. The clutch drum 24b and the clutch hub 24c each support alternately arranged brake discs 24d.

A piston 24e is fitted inside the support portion 24a, and a hydraulic oil chamber 24f is formed between the piston 24e and the support portion 24a. By controlling the supply of hydraulic oil to the hydraulic oil chamber 24f, the clutch disc 24d is pressed or released, and the third clutch device 20 is engaged or disengaged. This third clutch device 24 includes a diaphragm type return spring 24g for the piston 24e. The reason why a diaphragm type return spring is used in this third clutch device 24 is that this diaphragm type is thin and does not require a large space.

The fourth clutch device 27 is spline-coupled to the turbine shaft 13 and is integrally supported by a support portion 27a having a substantially inverted U-shaped cross section. clutch drum 2
7b. A clutch hub 27c is disposed inside the latch drum 27b, and the clutch hub 27c is supported by the carrier 14a of the planetary gear unit 14. The clutch drum 27b and clutch hub 27c each support alternately arranged brake discs 27d.

A piston 27e formed by sheet metal processing is fitted inside the support portion 27a. A hydraulic oil chamber 27f is formed between the piston 27e and the support portion 27a, and by controlling the supply of hydraulic oil to the hydraulic oil chamber 27f, the clutch disc 27d is pressed or released. Accordingly, the fourth clutch device 27 is engaged and disengaged. This fourth clutch also includes a diaphragm type return spring 27g, similar to the third clutch device 24 described above.

-The brake drum 23a of the first brake device 23 has a support portion 23c integrally supported by the large diameter sun gear 16.
Supported by Therefore, when the first brake device 23 operates, the large diameter sun gear 16 is fixed.

Second Brake 1 "萱25 This second brake device 25 is a disc type brake, and its brake drum 25a is connected to an annular member 26b (second one-way clutch 26) connected to the outer periphery of the carrier 14a of the planetary gear unit 14. The annular member 26b is supported by a support portion 25b connected to the inner race of the planetary gear unit 14, and is disposed between the case of the multi-speed gear device 10 and the annular member 26b. The carrier 14a is arranged to have a predetermined width in the outer axis direction.Therefore, when the second brake device 23 is activated, the carrier 14a is fixed.The support portion 25b, which is the annular member,
As shown enlarged in FIG. 3, the planetary gear unit has a predetermined width in the axial direction at its outer peripheral portion within the axial width of the planetary gear unit.

2 The multi-speed gear device 10 having the structure described above has four forward speeds and one reverse speed, and has first, second, third and fourth clutch devices 20.゜21.24 and 2
7. and first and second brake devices 23 and 2
A desired gear position can be obtained by operating 5 appropriately. In the above configuration, each gear stage and clutch,
The table below shows the operation relationship of the brakes.

(0) Transmission on the drive side Here, the first and second one-way clutches 22
The effects of and 26 will be explained.

The one-way clutch 26 of the second one-way clutch 2 is disposed adjacent to the second brake device 25 and between the annular member 26b (inner case) and the case 11, and is positioned at the first speed. Prevention of reverse rotation of carrier 14a and 1 to 2 gear shift and 2-1
It functions to determine the shift timing when shifting gears.

As can be seen from the table above, in 1st gear the carrier 14a
The carrier 14a must be allowed to rotate forward in the second gear, and the large diameter sun gear 16 must be fixed. Therefore, during the 1-2 gear shift, it is necessary to operate the means for freeing the carrier 14 and the means for fixing the large diameter sun gear 16, that is, the first brake device 23. If the means for freeing the carrier 14 is a band brake, it is necessary to first set the carrier 14a free and then fix the large diameter sun gear 16, resulting in a temporary neutral state and a time lag. On the other hand, when a one-way clutch is used as the above-mentioned means, as in this device, the carrier 14a becomes free and rotates forward at the moment the large-diameter sun gear 16 is fixed due to the action of the one-way clutch, so there is no time lag. It is possible to shift gears with good timing.

On the other hand, if the carrier 14a is fixed when shifting from the second speed state where the carrier 14a rotates forward and the ring gear 19 rotates at the second speed speed to the first speed, then the rotation of the ring gear 19 will change to the second speed. In comparison, the rotating bone of the carrier 14a tends to be lower. Therefore, if the carrier 14a is fixed unconditionally and all at once with the band brake, a shift shock will occur. In order to prevent this shift shock, it is sufficient to wait until the engine rotation increases to the first speed rotation or the vehicle speed decreases before shifting. However, the fixation of the carrier 14a and the large diameter sun gear 16
It would be extremely difficult to find the right timing to release the brake when using a band brake. Compared to that,
When using a one-way clutch, large diameter sun gear 16
Even after the carrier 14a is freed, the carrier 14a can continue to rotate at the second speed, and only when the speed reaches the same speed as the ring gear 19, the driving force from the small diameter sun gear 15 is transmitted, and the second gear is automatically rotated. -1 timing can be determined.

First one-way clutch 22 This one-way clutch 22 is used for 3-4 shifting and 4-3
It functions to determine the shift timing when shifting gears.

As can be seen from the table above, in 3rd gear, the clutch devices 21 and 27 are engaged and rotate together, while in 4th gear, the clutch 21 is released and the small diameter sun gear 15 rotates at an increased speed, and the large diameter sun gear 16 needs to be fixed. When performing 3-4 gear shifts under such conditions, if only a normal clutch is used, a temporary neutral state is required, but if a one-way clutch is used, the large-diameter sun gear 16 is simply fixed, and the moment Since the small diameter sun gear 15 increases the speed from the start, there is no time lag (3rd to 4th gear shifting can be performed with accurate timing).

On the other hand, in 4th gear, the small diameter sun gear 15 is rotating at an increased speed, so in order to shift from 4th gear to 3rd gear, the engine rotation speed (input rotation) must increase or the ring gear 19
Small diameter sun gear 1 until the rotation (output rotation) of
We have to wait for 5 to be fixed. It is difficult to obtain this timing with a normal clutch, but by using a one-way clutch, when the input rotation and the rotation of the small diameter sun gear 15 match, the driving force from the input side can be automatically transmitted, resulting in a good timing. You can change gears at the right time.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram illustrating the basic configuration of an automobile power transmission device according to an embodiment of the present invention, and FIG. 2 is an axial cross-section showing the structure of the multi-speed gear device shown in FIG. 1 in detail. FIG. 3 is an enlarged view of the main parts of the multi-speed gear device shown in FIG. 2. DESCRIPTION OF SYMBOLS 1... Crankshaft, 2... Torque converter, 10... Multi-speed gear device, 11... Case 12... Solid shaft. , 13... Turbine shaft, 14... Planetary gear unit, 15...
...Small diameter sun gear, 16...Large diameter sun gear, 17...Long pinion gear, 18...
・Short pinion gear, 19...Ring gear, 20...First clutch device, 21...
-Second clutch device, 22...First one-way clutch device, 23...First brake device, 24...Third clutch device, 25...・
...Second brake device, 26...Second one-way clutch, 26b...Annular member (inner case) 27...Fourth clutch device, 28...
...Output gear.

Claims (1)

[Scope of Claims] A torque converter and a multi-stage variable speed gear device are arranged coaxially with the engine crankshaft and sequentially from the engine side, the multi-stage variable speed gear device having a base end connected to a turbine of the torque converter, A turbine shaft whose tip extends to a side wall of the multi-speed gear device and is rotatably supported by the side wall; a small diameter sun gear, a large diameter sun gear, a long pinion gear, and a short pinion gear provided on the turbine shaft; A Ravigneaux-type planetary gear unit consisting of a carrier that holds both pinion gears and a ring gear, a second clutch device that connects and disconnects power transmission between the small-diameter sun gear and the turbine shaft, a case for the large-diameter sun gear and the multi-speed gear device; a third clutch device that engages and disengages the carrier of the Ravigneaux-type planetary gear and the case of the multi-speed gear device; A second brake device, a fourth clutch device that connects and disconnects power transmission between the carrier of the planetary gear unit and the turbine shaft, and an output gear connected to a ring gear of the planetary gear unit. In the apparatus, an annular member having a predetermined width in the axial direction is disposed on the outer circumference within the axial width of the Ravigneaux-type planetary gear unit, and the outer circumference of the carrier is connected to the annular member, and The second brake device and the second one-way clutch device are arranged adjacent to each other between the annular member and the case, and are arranged radially outward of the planetary gear unit. Power transmission device.