JP2003278797A - Speed change brake device of automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a speed change brake device wherein a band brake provided at the rear end of a transmission case is replaced by a multiple disc brake, while avoiding obstacles to a vehicle body around the rear end of the transmission case. <P>SOLUTION: Second- and sixth-speed brakes 2 and 6/B, which are positioned on the outer peripheries of a low clutch L/C and third- and fifth-speed and reverse brakes 3, 5 and R/B arranged in axially parallel relation on the outer periphery of a planetary gear set 4, are constructed of multiple disc brakes. A servo piston 27 is provided coaxially with this brake pack 26. The brakes 2 and 6/B, constructed of the multiple disc brakes, avoid variation and instability of transmission performance as compared with band brakes, and since part of pistons does not overhang greatly radially, decrease in degrees of freedom regarding installation is avoided. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift brake device for an automatic transmission, and more particularly to a technique for replacing a band brake, which is disadvantageous in terms of stability of shift performance and vehicle mountability, with a multiple disc brake. is there.

[0002]

2. Description of the Related Art Conventionally, as a gear shift mechanism of an automatic transmission, for example, Japanese Unexamined Patent Publication No. 2000-220704 and Japanese Unexamined Patent Publication No.
No. 000-220703 and Japanese Patent Laid-Open No. 2000-2207.
As described in Japanese Patent Publication No. 05-2005, there is known a gear speed change mechanism capable of performing a multi-speed shift by a decelerating planetary gear set that decelerates and outputs input rotation and a Ravigneaux planetary gear set that changes and outputs decelerated rotation from now on. Has been.

In this type of gear speed change mechanism, in particular, a gear speed change mechanism formed by combining a plurality of simple planetary gear sets is sometimes used.
A plurality of clutches are arranged side by side in the axial direction, a brake is arranged on the outer periphery of these clutches, and a predetermined transmission is performed by switching the transmission path by engaging and releasing the speed change friction elements including the two clutches and the brake. May be configured.

However, if the two clutches are arranged side by side in the axial direction on the outer circumference of the planetary gear set, and further the brakes are arranged on the outer circumference of these clutches, the automatic transmission has a large diameter at that portion. There is not much space available. Therefore, usually, a band brake is often used as the above-mentioned brake.

[0005]

However, in the band brake, the coefficient of friction of the band is likely to be varied, and the band brake is apt to change with time or temperature, and the engagement capacity at the time of engagement is varied or changed to cause variations in the shifting performance. However, the change over time and the change in shift performance due to temperature sometimes became a problem.

Further, although the band brake occupies a relatively small space in the radial direction of the automatic transmission, a servo piston for tightening the band in the circumferential direction to engage the brake is provided outside the transmission case. Since the servo piston is provided so as to project partially but largely, the servo piston sometimes causes a problem that the degree of freedom regarding installation of the automatic transmission is reduced.

In particular, the former two of the above-mentioned documents, JP-A-200
No. 0-220704 and Japanese Patent Laid-Open No. 2000-220703.
As described in Japanese Patent Laid-Open Publication No. 2005-242242, when the planetary gear set described above, two clutches on the outer peripheries of the planetary gear set, and brakes on the outer peripheries of these clutches are provided at the rear end of the transmission case far from the engine, Since the vehicle body protrudes around the rear end corner of the machine case, it is often not possible to accommodate the servo piston of the band brake, which largely projects in the radial direction.

According to the present invention, the brake provided on the outer circumference of the two clutches arranged side by side in the axial direction has a relatively small variation or change in the engagement capacity, and the shift performance can be easily stabilized.
Moreover, it is an object of the present invention to propose a shift brake device for an automatic transmission, which is constituted by a multi-disc brake in which a servo piston does not project in the radial direction like a band brake, and thereby solves all the above problems.

[0009]

For this purpose, a shift brake device for an automatic transmission according to the present invention has two clutches arranged axially side by side on the outer periphery of a planetary gear set as described in claim 1. However, in an automatic transmission in which brakes are arranged on the outer circumference of these clutches and gear shifting is performed by engaging and disengaging the two clutches and the friction elements for shifting, the brakes are composed of multiple disc brakes. A multi-disc brake servo piston is coaxially provided on a brake pack including a rotating plate and a non-rotating plate of the multi-disc brake.

For the same purpose, a shift braking device for an automatic transmission according to the present invention has a decelerating planetary gear set for decelerating an input rotation and outputting the decelerated planetary gear set. Multi-speed shifting is possible with a Ravigneaux type planetary gear set that shifts and outputs the rotation, and is arranged axially on the outer periphery of the reduction planetary gear set and the reduction planetary gear set in the rear end of the transmission case far from the engine. In an automatic transmission in which two clutches are provided and brakes are provided on the outer circumferences of these clutches, and shift control is performed by engaging and disengaging the two clutches and the shifting friction element including the brakes, the multiple brakes are provided. A multi-disc brake, which is composed of a multi-disc brake and is coaxial with a brake pack composed of a rotating plate and a non-rotating plate of the multi-disc brake. In which it characterized in that a Bopisuton.

[0011]

According to the configuration of the invention described in claim 1,
The brake arranged on the outer circumference of two clutches juxtaposed in the axial direction on the outer circumference of the planetary gear set is composed of a multi-plate brake, and since the servo piston is provided coaxially on the brake pack, the above brake is composed of a band brake. In this case, it is possible to avoid the variation and instability of the shift performance and always keep the shift quality high.

In addition, according to the present invention, since the above-mentioned brake is composed of a multi-disc brake, the servo piston does not partially largely extend in the radial direction unlike the band brake, and the above arrangement causes the servo piston to expand. Even though the diameter is large, the problem that the servo piston overhangs in the radial direction and reduces the degree of freedom regarding the installation of the automatic transmission can be solved.

According to a second aspect of the present invention, the planetary gear set is a decelerating planetary gear set that decelerates and outputs the input rotation, and the planetary gear set and a Ravigneaux that decelerates and outputs the decelerated rotation from the planetary gear set. The configuration of claim 1 described above is preferably adopted for an automatic transmission capable of performing multiple speed shifts by means of a type planetary gear set.

In this case, the same effect as described above can be achieved in the automatic transmission of the above type, the variation and instability of the shift performance can be avoided, and the shift quality can always be kept high. It is possible to solve the problem that the degree of freedom regarding the installation of the automatic transmission is reduced by avoiding the situation where the piston partially expands in the radial direction.

According to the third aspect of the present invention, the deceleration planetary gear set and the Ravigneaux type planetary gear set are capable of multistage shifting, and the deceleration planetary gear set and the deceleration planetary gear set are provided in the rear end portion of the transmission case far from the engine. Two clutches are provided on the outer circumference side by side in the axial direction and brakes are provided on the outer circumferences of these clutches, and shift control is performed by engaging and disengaging the two clutches and the shifting friction element including the brakes. Assuming that the transmission is a multi-disc brake, the brake pack is provided with a servo piston for the multi-disc brake coaxially.Therefore, there are variations in transmission performance when the above brake is a band brake. You can avoid instability and keep the gear quality high at all times, and at the same time, use a servo fix like a band brake. There it is possible to solve the problem that the degree of freedom regarding the installation of the automatic transmission to avoid a situation where projecting largely to partially radial direction is reduced.

In the case of the construction according to claim 3, it is preferable that the brake pack of the multi-disc brake is arranged on the engine side and the servo piston is arranged on the side far from the engine, as described in claim 4. . In this case, since the servo piston has a smaller diameter than that of the brake pack, it is possible to reduce the outer diameter of the rear end of the transmission case, which makes it easier to avoid vehicle interference near the outer periphery of the rear end of the transmission case. The plate that constitutes the brake pack can make the solution to the problem of lowering the degree of freedom regarding the installation of the machine more reliable, and can increase the diameter of the brake pack without being affected by the vehicle body interference. It is even possible to reduce the axial dimension of the automatic transmission by reducing the number of.

Here, when the servo piston of the brake is arranged as described in claim 4, as described in claim 5, the servo piston is a stepped piston whose diameter becomes smaller toward the end face farther from the brake pack. Good to do. In this case, the diameter of the servo piston becomes smaller at the end farther from the engine, and the rear end edge of the transmission case can be made smaller in accordance with this, further avoiding vehicle body interference near the outer periphery of the rear end of the transmission case. It is possible to make the solution to the problem that the degree of freedom regarding the installation of the automatic transmission is reduced more easily and more reliably.

It is preferable that the clutch pack relating to the two clutches described in claims 2 to 5 is composed of clutch plates having the same specifications as described in claim 6, and in this case, parts of both clutches. The cost can be reduced and the workability of assembling the clutch can be improved.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a gear shift mechanism of an automatic transmission having a shift brake device according to an embodiment of the present invention, and FIG. 2 shows the relationship between the selected shift speed and the engagement logic of a shift friction element. It is a drawing shown. As shown in FIG. 1, a gear transmission mechanism according to this embodiment has an input shaft 1 and a hollow output shaft 2 coaxially arranged so as to surround the input shaft 1.
The rotation of the engine (not shown) is input to the input shaft 1 from the right end of the drawing. Then, the Ravigneaux type planetary gear set 3 and the deceleration planetary gear set 4 are provided in order from the side closer to the engine by being arranged coaxially with the input / output shafts 1 and 2.

The deceleration planetary gear set 4 includes a sun gear S1, a ring gear R1, and a pinion P1 meshed with these gears.
Is a simple planetary gear set consisting of a carrier C1 that rotatably supports the Ravigneaux planetary gear set 3.
Long pinion P2 and short pinion P3 meshing with each other, and sun gear S meshing with long pinion P2
2 and the sun gear S3 meshing with the short pinion P3
And a ring gear R3 meshed with the long pinion P2,
Carrier C2 that rotatably supports long pinion P2
And a carrier C3 that rotatably supports a long pinion P2 and a short pinion P3. Here, the carrier C2 and the carrier C3 are integrated.

Output shaft 2 from input shaft 1 via reduction planetary gear set 4 and Ravigneaux type planetary gear set 3.
In the following, the speed change friction element that determines the transmission path (selection speed) to the input shaft 1 is connected to the ring gear R1, and the output shaft 2 is connected to the ring gear R3 at one end and the output gear at the other end. Bind to 5. And the sun gear S1
Is fixed to the transmission case 6 at all times, and the carrier C1 can be connected to the sun gear S3 by the low clutch L / C, and can be connected to the sun gear S2 by the third speed, the fifth speed and the reverse clutch 3.5 / R / C. In addition, 2 Sun Gear S2
It can be fixed to the transmission case 6 by the 6th and 6th speed brakes 2.6 / B. The carriers C2 and C3 prevent rotation in the direction opposite to the engine by the low one-way clutch L / OWC, and can be appropriately fixed by the low reverse brake LR / B, and can be appropriately coupled to the input shaft 1 by the high clutch H / C. To do.

The above-mentioned speed change friction elements, that is, the low clutch L / C, the third speed, the fifth speed, and the reverse clutch 3.5 / R / C.
2nd and 6th speed brake 2.6 / B, low one way clutch L / OWC, low reverse brake LR / B
With the high clutch H / C, the forward first to sixth speeds and the reverse speed can be selected by a combination of the engagements (shown by ◯) shown in FIG.

When selecting the first speed, the low clutch L / C is engaged as shown in FIG. 2 to transmit power along the following transmission path. That is, the rotation of the input shaft 1 is transmitted to the ring gear R1, and the ring gear R1 uses the fixed sun gear S1 as a reaction force receiver to rotate the carrier C1 under deceleration in the same direction as the input rotation, and this decelerated rotation is performed by the low clutch L / C. It is transmitted to the sun gear S3.

The sun gear S3 is provided with a short pinion P3 and a long pinion P2 because the carrier C2 is prevented from rotating in the direction opposite to the engine rotation by the engagement of the low one way clutch L / OWC and serves as a reaction force receiver. By rotating the ring gear R3 together with the output shaft 2 and the output gear 5 in the same direction as the engine rotation under deceleration, the forward first speed selection state can be realized.

In the first speed selection state, the carrier C2 is rotated in the same direction as the rotation of the engine during traveling in which the engine brake should be applied, and the reaction force is no longer used. Therefore, the engine brake cannot be applied. Therefore, when engine braking is required in the first speed selection state, the low reverse brake LR / B is engaged as shown by (○) in FIG. 2 to prevent the carrier C2 from rotating in the same direction as the engine rotation. As a result, engine braking at the first speed is obtained.

In selecting the second speed, as shown in FIG. 2, the low clutch L / C and the second and sixth speed brakes 2.6 are used.
By connecting / B, power is transmitted along the following transmission paths. That is, the input rotation to the shaft 1 is reduced by the planetary gear set 4 in the same manner as when the first speed is selected, and the low clutch L
/ C to reach Sun Gear S3.

In the sun gear S3, the sun gear S2 is in the second speed and the sixth speed.
Since the rotation is blocked by the engagement of the fast brake 2.6 / B to serve as a reaction force receiver, the ring gear R3 together with the output shaft 2 and the output gear 5 is rotated through the short pinion P3 and the long pinion P2 as the engine rotation. It is possible to realize the forward second speed selection state by rotating the motor in a decelerating direction, but at a higher speed than when the first speed is selected.

When selecting the third speed, as shown in FIG. 2, the low clutch L / C, the third speed, the fifth speed, and the reverse clutches 3.5 / R / C are engaged to transmit power along the following transmission paths. Let it be done. That is, the input rotation of the shaft 1 is reduced by the planetary gear set 4 in the same manner as when the first speed is selected, and this reduced rotation is transmitted to the sun gear S3 via the low clutch L / C.
It also reaches the sun gear S2 through the third and fifth speeds and the reverse clutch 3.5 / R / C.

Therefore, the sun gear S2 and the sun gear S3 are integrally rotated, and the Ravigneaux planetary gear set 3 moves the ring gear R3 together with the output shaft 2 and the output gear 5 at the same speed as the sun gear S2 and the sun gear S3, but when the second speed is selected. It is possible to realize a forward third speed selection state by rotating at a higher speed.

When selecting the fourth speed, as shown in FIG. 2, the low clutch L / C and the high clutch H / C are engaged to transmit power along the following transmission paths. That is, the input rotation of the shaft 1 is decelerated by the planetary gear set 4 in the same manner as when the first speed is selected, and the decelerated rotation from now on reaches the sun gear S3 via the low clutch L / C.

On the other hand, since the carrier C3 is rotated at the same speed as the engine rotation by the engagement of the high clutch H / C, the Ravigneaux type planetary gear set 3 causes the ring gear R3 to move to the output shaft 2 and the output gear by the decelerated rotation to the sun gear S3. It is possible to realize the forward fourth speed selection state by rotating the motor 5 in the same direction as the engine rotation, but at a higher speed than when the third speed is selected.

When selecting the fifth speed, as shown in FIG. 2, the third speed, the fifth speed, the reverse clutches 3.5 / R / C and the high clutch H / C are engaged to transmit power along the following transmission paths. Let it be done. That is, the input rotation of the shaft 1 is decelerated by the planetary gear set 4 in the same manner as when the first speed is selected, and the decelerated rotation from now on is the third speed, the fifth speed, and the reverse clutches 3.5.
The sun gear S2 is reached via R / C.

On the other hand, since the carrier C3 is rotated at the same speed as the engine rotation by engaging the high clutch H / C, the Ravigneaux planetary gear set 3 causes the ring gear R3 to move to the output shaft 2 and the output gear due to the decelerated rotation to the sun gear S2. It is possible to realize the forward fifth speed selection state by rotating together with No. 5 in the same direction as the engine rotation, but at a higher speed than when the fourth speed is selected.

In selecting the sixth speed, as shown in FIG. 2, the high clutch H / C and the second and sixth speed brakes 2.6
By connecting / B, power is transmitted along the following transmission paths. That is, the carrier C3 is rotated at the same speed as the engine rotation by the engagement of the high clutch H / C, the rotation of the sun gear S2 is blocked by the engagement of the second and sixth speed brakes 2.6 / B, and functions as a reaction force element. , The Ravigneaux planetary gear set 3 rotates the ring gear R3 together with the output shaft 2 and the output gear 5 in the same direction as the engine rotation, but at a higher speed than in the case where the fifth speed is selected, thereby realizing the forward sixth speed selection state. it can.

When selecting reverse, power transmission is performed along the following transmission paths by engaging the third and fifth speeds, the reverse clutches 3.5 / R / C and the low reverse brake LR / B as shown in FIG. Let That is, the input rotation of the shaft 1 is decelerated by the planetary gear set 4, and the decelerated rotation from now on reaches the sun gear S2 via the third speed, the fifth speed, and the reverse clutch 3.5 / R / C.

On the other hand, the engagement of the low reverse brake LR / B blocks the rotation of the carrier C2, which functions as a reaction force element. Therefore, the decelerated rotation to the sun gear S2 is reversed by the long pinion P2 and reaches the ring gear R3. Reverse rotation can be taken out from the output shaft 2 and the output gear 5, and a backward selection state can be realized.

The actual structure of the gear transmission mechanism shown in FIG. 1 is as shown in FIG. 3 only for the essential parts, but in the present embodiment, particularly, the low reverse brake LR / B.
In addition to the 2nd and 6th speed brakes 2.6 / B, they are composed of multiple disc brakes as will be described in detail later.

In the transmission case 6, the input shaft 1 driven by an engine (not shown) is inserted from the right side of FIG.
The insertion end is supported in a hollow fixed shaft 11 that projects in the rear end 6a of the transmission case 6 remote from the engine. The Ravigneaux type planetary gear set 3 and the reduction planetary gear set 4 are provided on the input shaft 1 and the hollow fixed shaft 11, respectively, and the Ravigneaux type planetary gear set 3 on the engine side rotates its carrier C3 onto the input shaft 1. The sun gear S1 of the deceleration planetary gear set 4 on the side far from the engine is mounted on the hollow fixed shaft 11 with serrations.

The ring gear R3 of the Ravigneaux type planetary gear set 4 is connected to the output gear 5 via the output shaft 2,
The output gear 5 is rotatably supported on the transmission case 6 by bearings 12. The carrier C2 is coupled to the rotating member 13 which also serves as the inner race of the low one-way clutch L / OWC and the hub of the low reverse brake LR / B. The outer race of the rowan way clutch L / OWC is spline-fitted to the inner circumference of the transmission case 6 and is axially positioned by the snap ring 14. The low reverse brake LR / B includes a brake pack 15 in which a rotating plate spline-fitted to the outer circumference of the rotary member 13 and a non-rotating plate spline-fitted to the inner circumference of the transmission case 6 are alternately arranged. It is assumed that the brake pack 15 is brought into an engaged state when the brake pack 15 is pressed toward the outer race of the low one way clutch L / OWC by the hydraulic piston 17 that strokes in the cylinder 16 provided on the front end wall of the case 6.

The sun gear S3 is connected to the clutch hub 18 of the low clutch L / C, the sun gear S2 is connected to one end of the rotary drum 19, and the other end of the rotary drum 19 is rotatably supported on the hollow fixed shaft 11. . The rotary drum 19 includes a planetary gear set 4 for deceleration and a low clutch L / C capable of transmitting decelerated rotation from the planetary gear set 4 to the sun gears S2, S3, a third speed, a fifth speed, and a reverse clutch 3, 5, R / C. It has a large diameter so that a low clutch is provided between the rotary drum 19 and the clutch hub 18.
The L / C clutch drum 20 is interposed. The clutch drum 20 has an inner peripheral portion that is a carrier C1 of the planetary gear set 4 for speed reduction.
To engage the ring gear R1 of the reduction planetary gear set 4 with the input shaft 1.

The low clutch L / C comprises a clutch pack 21 in which a clutch plate spline-fitted to the clutch hub 18 and a clutch plate spline-fitted to the inner periphery of the clutch drum 20 are alternately arranged. Servo piston 22 that controls clutch L / C engagement
Is slidably fitted in the clutch drum 20. The third, fifth, and reverse clutches 3, 5 and R / C include a clutch hub 23 connected to the clutch drum 20, a clutch plate splined to the clutch hub 23, and a spline fitting to the inner circumference of the clutch rotating member 19. And a clutch pack 24 in which the fitted clutch plates are alternately arranged. By pressing the clutch pack 24, the third speed, the fifth speed,
A servo piston 25 that controls the engagement of the reverse clutches 3, 5, and R / C is slidably fitted in the rotary member 19.

By the way, the low clutch L / C and the third speed,
5th speed, reverse clutch 3, 5 and R / C clutch pack 2
1, 24 are arranged side by side in the axial direction so that the low clutch L / C is on the engine side.
All 24 clutch plates have the same specifications,
Low clutch L / C and 3rd and 5th speed, reverse clutch 3
・ 5 ・ R / C cost reduction and improvement of assembly workability.

As described above, the decelerating planetary gear set 4 and the low clutch L / C for selectively directing the decelerated rotation from this (from the carrier C1) to the sun gears S2 and S3 and the third speed, the fifth speed, and the reverse speed Clutch 3, 5 and R / C are rotating members 1
9 and is united, and this unit is arranged on the hollow fixed shaft 11 and the rear end portion 6a of the transmission case 6 is provided.
Store inside.

The second-speed and sixth-speed brakes 2, 6 / B are arranged alternately with a rotating plate spline-fitted to the outer periphery of the rotating member 19 and a non-rotating plate spline-fitted to the inner periphery of the transmission case 6. A brake pack 26 is provided, and this brake pack 26 is arranged on the outer periphery of the low clutch L / C and abutted against the outer race of the low one way clutch L / OWC. Brake pack 26 to rowan way clutch L / O
2nd and 6th speed brakes pressed against the outer race of WC 2
The servo piston 27 that controls 6 / B is arranged on the side farther from the engine than the brake pack 26, and the servo piston 27 is slidable in the annular recess 28 provided in the rear end wall of the transmission case 6. To fit.

The annular recess 28 and the rear end portion of the servo piston 27 slidably fitted in the annular recess 28 are stepped so that the diameter becomes smaller toward the end face farther from the brake pack 26 to define two cylinder chambers. However, by supplying these cylinder chambers selectively or both, 2nd and 6th speed brakes
Make it possible to adjust the fastening capacity of 2.6B.

By the way, in the present embodiment having the above-mentioned substantive structure, the low clutch L / C and the third speed, the fifth speed, and the reverse brakes 3.5 that are juxtaposed on the outer periphery of the reduction planetary gear set 4 in the axial direction are arranged. The second and sixth speed brakes 2 and 6 / B arranged on the outer periphery of the R / B are composed of multiple disc brakes like the low reverse brake LR / B, and the servo piston 27 is coaxially provided in the brake pack 26. It is possible to constantly maintain high shift quality by avoiding variations and instability in shift performance when the above-described second speed and sixth speed brakes 2 and 6 / B are band brakes.

In addition, according to the present embodiment, since the 2nd and 6th speed brakes 2/6 / B are composed of multi-plate brakes, the servo piston is partially radiated as in the case of a band brake. However, even though the circumference of the speed-reducing planetary gear set 4 has a large diameter due to the three-tiered radial structure, the servo piston overhangs in the radial direction and the automatic transmission It is possible to solve the problem of lowering the degree of freedom regarding installation.

Further, according to the present embodiment, the second-speed and sixth-speed brakes 2.6 / B composed of the multiple disc brakes as described above.
Since the brake pack 26 is arranged on the engine side and the servo piston 27 is arranged on the side far from the engine, the following operational effects can be obtained. That is, since the servo piston 27 has a smaller diameter than that of the brake pack 26, the outer diameter of the rear end portion 6a of the transmission case 6 can be reduced, and the vehicle body interference near the outer periphery of the rear end portion of the transmission case 6 can be reduced. 29 can be avoided easily, and the problem that the degree of freedom regarding the installation of the automatic transmission is reduced can be reliably solved.
The brake pack 26 can have a large diameter without being affected by the vehicle body obstacle 29, and the axial size of the automatic transmission can even be reduced by reducing the number of plates constituting the brake pack 26.

Further, in the present embodiment, the rear end of the servo piston 27 slidably fitted in the annular recess 28 formed in the rear end 6a of the transmission case 6 is connected to the brake pack 26.
Since the diameter becomes smaller toward the end face farther from the engine, the diameter of the servo piston 27 becomes smaller at the end farther from the engine, which corresponds to the rear end 6 of the transmission case 6.
As can be seen from FIG. 3, the peripheral edge of a can be made small in diameter, and it becomes easier to avoid the vehicle body interfering substance 29 in the vicinity of the outer periphery of the rear end of the transmission case 6, thereby reducing the degree of freedom in installing the automatic transmission. The problem can be solved more reliably.

FIG. 4 shows a gear shift mechanism of an automatic transmission having a shift brake device according to another embodiment of the present invention. The gear shift mechanism is coaxial with the input shaft 1 and surrounding the input shaft 1. A hollow output shaft 2 is provided, and the input shaft 1 receives the rotation of the engine (not shown) from the right end of the drawing. Then, the planetary gear set 4 for reduction and the Ravigneaux type planetary gear set 3 are arranged in order from the side closer to the engine by being arranged coaxially with the input / output shafts 1, 2.

The deceleration planetary gear set 4 includes a sun gear S1, a ring gear R1, and a pinion P1 meshed with these gears.
Is a simple planetary gear set consisting of a carrier C1 that rotatably supports the Ravigneaux planetary gear set 3.
Long pinion P2 and short pinion P3 meshing with each other, and sun gear S meshing with long pinion P2
2 and the sun gear S3 meshing with the short pinion P3
And a ring gear R3 meshed with the long pinion P2,
Carrier C2 that rotatably supports long pinion P2
And a carrier C3 that rotatably supports a long pinion P2 and a short pinion P3. Here, the carrier C2 and the carrier C3 are integrated.

Output shaft 2 from input shaft 1 via reduction planetary gear set 4 and Ravigneaux type planetary gear set 3.
In the following, the speed change friction element that determines the transmission path (selection speed) to the input shaft 1 is connected to the ring gear R1, and the output shaft 2 is connected to the ring gear R3 at one end and the output gear at the other end. Bind to 5. And the sun gear S1
Is fixed to the transmission case 6 at all times, and the carrier C1 can be connected to the sun gear S3 by the low clutch L / C, and can be connected to the sun gear S2 by the third speed, the fifth speed and the reverse clutch 3.5 / R / C. In addition, 2 Sun Gear S2
It can be fixed to the transmission case 6 by the 6th and 6th speed brakes 2.6 / B. The carriers C2 and C3 prevent rotation in the direction opposite to the engine by the low one-way clutch L / OWC, and can be appropriately fixed by the low reverse brake LR / B, and can be appropriately coupled to the input shaft 1 by the high clutch H / C. To do.

In the gear shift mechanism having the above structure, the deceleration planetary gear set 4 decelerates the input rotation from the engine and outputs it to the carrier C1, and the Ravigneaux type planetary gear set 3 decelerates the planetary gear set 4 ( Carrier C1)
The decelerated rotation from the ring gear R is changed as described later.
By outputting to 3, it is possible to carry out multi-stage gear shifting.

The above-mentioned speed change friction elements, that is, the low clutch L / C, the third speed, the fifth speed, and the reverse clutch 3.5 / R / C.
2nd and 6th speed brake 2.6 / B, low one way clutch L / OWC, low reverse brake LR / B
In the high clutch H / C, the forward first to sixth speeds and the reverse speed can be selected in the same manner as in the above-described embodiment by a combination of engagements (shown by ◯) shown in FIG. The output rotation from the output gear 5 can be transmitted to the left and right drive wheels (not shown) sequentially through the counter gear 7, the counter shaft 8, the final drive gear set 9 and the differential gear device 10 at each selected speed.

The actual structure of the gear shift mechanism shown in FIG. 4 is basically the same as that described in Japanese Patent Application Laid-Open No. 2000-220705, but in this embodiment, only the essential parts thereof are shown in FIG. 2nd, 6th speed brake 2
・ Replace 6 / B with band brakes as described below.

To explain the configuration shown in FIG. 5, the sun gear S1, the ring gear R1, and the pinion P1 are as described above with reference to FIG.
And a decelerating planetary gear set 4 composed of a carrier C1 and decelerated rotation from the planetary gear set 4 (more specifically, from the carrier C1) to a sun gear S3 of the Ravigneaux planetary gear set 3 shown in FIG. Low clutch L / C for transmission, and planetary gear set 4 (carrier C1)
3rd and 5th gears for transmitting the decelerated rotation from to the sun gear S2 of the Ravigneaux type planetary gear set 3 shown in FIG. 4 via the rotating drum 32, and the reverse clutches 3.5 / R / C,
The rotary drum 32 is wrapped to form a unit, which is housed in the front end of the opening of the transmission case 6 on the engine side (the right side in FIG. 5) and arranged on the input shaft 1.

The front end of the opening of the transmission case 6 is closed by a pump case 36 which is a combination of a pump housing 34 containing a gear type oil pump 33 and a pump cover 35. The pump case 36 is bolted to the transmission case 36. Attach to 6. A hollow fixed shaft 38 is fixed to the pump case 36 through its center, and the sun gear S1 of the reduction planetary gear set 4 is rotationally engaged with the inner end of the hollow fixed shaft 38.

The input shaft 1 is rotatably installed in the hollow fixed shaft 38, and the ring gear R1 of the reduction planetary gear set 4 is rotatably engaged with the outer periphery of the flange 39 projecting radially from the input shaft 1. . A clutch hub 40 is provided so as to surround the ring gear R1 and is rotationally engaged with the carrier C1 of the reduction planetary gear set 4 so as to rotate therewith. The clutch hub 40 is also used for the low clutch L / C, the third speed, the fifth speed, and the reverse clutches 3, 5, and R / C, and the clutch plate spline-fitted to the clutch hub 40 and the clutch drum 31 spline-fitted. The clutch pack 41 of the low clutch L / C is configured by the alternate arrangement of the plates, and the alternate arrangement of the clutch plate spline-fitted to the clutch hub 40 and the clutch plate spline-fitted to the clutch drum 32 causes the third speed, the fifth speed, and the reverse. The clutch pack 42 for the clutches 3, 5 and R / C is configured.

The clutch plates constituting the clutch packs 41 and 42 have the same specifications for both clutches, and are arranged side by side in the axial direction. Then, the clutch pack 41 is pushed rightward in FIG.
The servo piston 43 for engaging the L / C is slidably fitted in the clutch drum 31, and the clutch pack 42 is shown in FIG.
Push to the left of 3rd speed, 5th speed, reverse clutch 3.5 / R / C
Servo piston 44 for engaging the clutch drum 32
Slidably fit inside.

In the present embodiment, the second and sixth speed brakes 2.6 / B for fixing the clutch drum 32 and preventing the rotation of the sun gear S2 coupled thereto are provided as follows. It is composed of plate brakes. In other words, the second speed and sixth speed brakes 2/6/6 are provided by alternate positions of the rotary plate spline-fitted on the outer circumference of the clutch drum 32 and the non-rotating plate spline-fitted on the inner circumference of the transmission case 6. The B brake pack 45 is configured. Then, push this brake pack 45 to the right in FIG.
Pistons for engaging the 6th and 6th speed brakes 2, 6 / B
A cylinder device 46 (consisting of a piston 47 and a cylinder 48) is fitted and provided in the transmission case 6.

Also in this embodiment described above, the low clutch is arranged in parallel on the outer periphery of the reduction planetary gear set 4 in the axial direction.
L / C and 3rd and 5th speeds, 2nd and 6th speed brakes 2 and 6 / B arranged on the outer periphery of the reverse brake 3/5 / R / B are composed of multiple disc brakes and are coaxial with the brake pack 45. Since the servo piston 47 is provided in the second gear, it is possible to avoid the variation and instability of the shift performance in the case where the above-described second speed and sixth speed brake 2/6 / B is configured by the band brake, and always maintain the high shift quality.

In addition, according to the present embodiment, since the 2nd and 6th speed brakes 2/6 / B are composed of multi-plate brakes, the servo piston is partially radiated as in the case of a band brake. However, even though the circumference of the speed-reducing planetary gear set 4 has a large diameter due to the three-tiered radial structure, the servo piston overhangs in the radial direction and the automatic transmission It is possible to solve the problem of lowering the degree of freedom regarding installation.

[Brief description of drawings]

FIG. 1 is a schematic diagram schematically showing a speed change gear mechanism of an automatic transmission including a speed change brake device according to an embodiment of the present invention.

FIG. 2 is an engagement logic explanatory diagram showing a relationship between engagement of a shifting friction element and a selected gear in the gear transmission mechanism.

FIG. 3 is an actual configuration diagram of the gear shift mechanism, enlarging and showing an essential part of the shift brake device according to the embodiment.

FIG. 4 is a schematic diagram schematically showing a speed change gear mechanism of an automatic transmission including a speed change brake device according to another embodiment of the present invention.

FIG. 5 is an actual configuration diagram of the gear shift mechanism, enlarging and showing an essential part of the shift brake device according to the embodiment.

[Explanation of symbols]

1 input axis 2 output shaft 3 Ravigno type planetary gear set 4 Planetary gear set for deceleration S1 sun gear R1 ring gear P1 pinion C1 career P2 long pinion P3 short pinion S2 sun gear S3 sun gear R3 ring gear C2 career C3 career 5 output gears 6 transmission case 6a Transmission case rear end L / C low clutch 3/5 R / C 3rd, 5th, reverse clutch 2/6 / B 2nd and 6th brakes L / OWC low one way clutch LR / B low reverse brake H / C high clutch 11 Hollow fixed shaft 12 bearings 13 Rotating member 14 snap ring 15 brake pack 16 cylinders 17 Hydraulic piston 18 clutch hub 19 rotating drum 20 clutch drum 21 clutch pack 22 Servo piston 23 Clutch hub 24 clutch pack 26 brake pack 27 Servo piston 28 annular depression 29 Car body obstacle 31 rotating drum 32 rotating drum 33 Oil pump 34 Pump housing 35 Pump cover 36 pump case 38 Hollow fixed shaft 39 flange 40 clutch hub 41 clutch pack 42 clutch pack 43 Servo piston 44 Servo piston 45 brake pack 46 Piston / Cylinder device

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3J028 EA21 EA25 EB08 EB13 EB31                       EB35 EB37 EB62 EB66 FA14                       FB06 FC18 FC25 FC62 FD30                       GA01                 3J057 AA04 BB04 FF01 FF10 FF12                       FF15 GA11 GA64 JJ04                 3J063 AA02 AB12 AC03 BA03 CA01                       CD14 CD17 CD26

Claims (6)

[Claims] 1. A planetary gear set is provided with two clutches arranged side by side in the axial direction, brakes are provided on the outer circumferences of these clutches, and engagement and release of the two clutches and a shifting friction element including the brakes. In the automatic transmission adapted to shift gears, the brake is constituted by a multi-disc brake, and a servo piston for the multi-disc brake is coaxially provided on a brake pack consisting of a rotating plate and a non-rotating plate of the multi-disc brake. A gear shifting brake device for an automatic transmission characterized by the above. 2. The planetary gear set is a decelerating planetary gear set that decelerates and outputs input rotation, and the planetary gear set and a Ravigneaux planetary gear set that decelerates and outputs decelerated rotation from the planetary gear set. The shift brake device for an automatic transmission according to claim 1, wherein a multi-speed shift is enabled by the. 3. A deceleration planetary gear set that decelerates and outputs input rotation, and a Ravigneaux planetary gear set that decelerates and outputs decelerated rotation from the planetary gear set, so that multi-stage shifting is possible and a gear shifting far from the engine is possible. Inside the rear end of the machine case, the deceleration planetary gear set and two clutches are arranged axially side by side on the outer circumference of the deceleration planetary gear set, and a brake is provided on the outer circumference of these clutches. In an automatic transmission in which gear shifting is controlled by engaging and releasing friction elements for gear shifting, the brake is constituted by a multi-disc brake and is coaxial with a brake pack composed of a rotating plate and a non-rotating plate of the multi-disc brake. A shift brake device for an automatic transmission, characterized in that a servo piston for multi-disc brake is provided in the. 4. The automatic transmission gear shifting brake device according to claim 3, wherein the brake pack of the multi-disc brake is arranged on the engine side, and the servo piston is arranged on the side far from the engine. Brake device for shifting gears. 5. The shift brake device for an automatic transmission according to claim 4, wherein the servo piston of the multi-disc brake is a stepped piston having a diameter that decreases toward an end face farther from the brake pack. Brake device for shifting automatic transmission. 6. The shift brake device for an automatic transmission according to claim 2, wherein a clutch pack relating to the two clutches is formed of a clutch plate having the same specifications. Brake device for shifting automatic transmissions.