JPH01141257A - Power train of automatic transmission - Google Patents

Abstract

PURPOSE:To enable adaptation for FR and FF vehicles by integrating first and second inner pinions then coupling first and second pinion carriers of both planetary gear sets integrally and taking out from splitting section of first and second sun gears. CONSTITUTION:A first pinion P1 and a second inner pinion are integrated while a sun gear is splitted into first and second sun gears S1, S2, while first and second pinion carriers of front and rear planetary gear sets FR, RP are coupled each other to provide an integrated pinion carrier PC which is taken out from a splitting section of the sun gears S1, S2. First and second ring gears R1, R2 are provided couplably/releasably through first and second clutches C1, C2 for an inlet shaft I, while first or second sun gear S1 or S2 is provided stoppably/ releasably through a brake for a case K. Take-out section of the pinion carrier PC is coupled to an output shaft O.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a power train for an automatic transmission that provides four forward gears.

(Prior Art) Conventionally, as a power train for an automatic transmission with four forward speeds, the one shown in FIG. 7, which is cited as a conventional example in Japanese Patent Laid-Open No. 62-93545, is known.

Further, as an improved version of this, the ones shown in FIGS. 1 to 6 of the same publication are known.

(Problems to be Solved by the Invention) However, in the device shown in FIG. 7 of the conventional publication, the shaft size can be shortened by the Lavigneau type gear train, and it can be used in both FF and FR vehicles. As stated in the publication, it is a sun gear input, which is disadvantageous in terms of strength.

On the other hand, in the devices shown in Figures 1 to 6 of the conventional publication, although the above problem could be solved by using a ring gear input, the output is from a pinion carrier, and the sun gear is integrally shared across two ring gears. It has been transformed into

For this purpose, as described in the conventional gazette, a cylindrical gear shaft that is engaged with the sun gear is arranged to extend in the axial direction on the outer periphery of the input shaft, and a cylindrical gear shaft that is engaged with the pinion carrier is arranged on the outer periphery of the gear shaft. Extend the shaped output shaft in the axial direction,
This output shaft has a structure in which a counter drive gear is provided, that is, an output is taken out in a direction orthogonal to the input/output shaft.

Therefore, it can be applied to FF cars, but it cannot be applied to FR cars that require an axial extraction structure, and furthermore,
The input/output shaft and gear shaft result in a coaxial triple shaft structure, resulting in high costs. In addition, JP-A-62-9
The device described in Publication No. 3546 also has the same drawbacks as above.

(Means for Solving the Problems) The present invention has been made for the purpose of solving the above-mentioned problems, and in order to achieve this purpose, the present invention has a first sun gear and a second ring gear. A single pinion type first pinion having a first pinion that meshes with these and a first pinion carrier that rotatably supports the first pinion.
The planetary gear set, the second sun gear, the second inner pinion that meshes with it, the second ring gear and the second inner pinion, the second outer pinion that meshes with both the second ring gear, and both the second inner and outer pinions are rotatable. Two planetary gear sets, a double pinion type second planetary gear set having a supporting second pinion carrier, are arranged between the input shaft and the output shaft, and a multi-speed transmission is achieved by operating combinations of transmission elements such as clutches and brakes. In the power train of an automatic transmission, the first pinion and the second inner pinion are integrated, and the sun gear is separated and separated as the first sun gear and the second sun gear, respectively. ,
The first and second pinion carriers of both planetary gear sets are connected to each other and integrated, and taken out from the divided portion of both sun gears, and the second ring gear and the first ring gear are connected to the first and second ring gears with respect to the human power shaft. Connected via 2 clutches.

It is provided releasably, and the first sun gear or second sun gear is held stationary via a brake against the case.

Means characterized in that the second ring gear is provided so as to be releasable, the second ring gear is prevented from rotating in one direction and is rotatable in the other direction via a one-way clutch, and the take-out portion of the pinion carrier is connected to the output shaft. did.

(Function) At l-speed, if only the second clutch is operated to connect the human power shaft and the first ring gear, the one-way clutch will operate to prevent the second ring gear from rotating in the reverse direction, and the input shaft will be rotated from the input shaft to the first ring gear. Power is transmitted from the first ring gear to the first pinion to the pinion carrier to the output shaft, and a l-speed gear with a large reduction gear ratio is obtained from the output shaft.

When in second gear, the second clutch and second brake are operated, the input shaft and the first ring gear are connected, and the second sun gear is held stationary in the case, so that the human power shaft → the first ring gear, the first pinion, and the pinion carrier. →The power is transmitted to the output shaft, and from the output shaft, a 2nd speed gear position with a smaller reduction gear ratio than 1st speed is obtained.

At 3rd speed, when the first clutch and the second clutch are operated and the input shaft is connected to the first ring gear and the second ring gear, the human power shaft - the first ring gear (second ring gear) is connected.
Power is integrally transmitted from the output shaft to the first pinion (second outer pinion), the pinion carrier, and the output shaft, and a three-speed gear position with a gear ratio I is obtained from the output shaft.

In 4th gear, when the first clutch and second brake are activated, the input shaft and second ring gear are connected, and the first sun gear or second sun gear is stationary on the case, the input shaft → second ring → second Power is transmitted from the outer pinion to the pinion carrier to the output shaft, and from the output shaft, a 4-speed gear stage is obtained by increasing the speed at a gear ratio l or less.

Therefore, while obtaining four forward speeds, it is basically compact because it is a Lavigneau type gear train, has an advantage in strength due to the ring gear input, and has a pinion carrier output due to the sun gear being divided into two. However, it is possible to simultaneously achieve continuous window windows for FR and FF cars, and simplify the output extraction structure by requiring only two coaxial shafts.

(Example) Embodiments of the present invention will be described below based on the drawings.

First, the configuration will be explained.

The power train of the automatic transmission according to the embodiment is as follows.

As shown in Figure 1, which is an FR vehicle specification and a skeleton with the axisymmetric lower half omitted, the gear train is
Front planetary gear set (first planetary gear set) FP disposed between input shaft I and output shaft O
and a rear planetary gear set (second planetary gear set) RP.

In addition, as shift elements, a first clutch (first clutch) C1, a second clutch C2 (second clutch) C2, a third clutch C3, a first brake B1 . Second brake (brake) B2. 1st one-way clutch (one-way clutch) OWC.

, and the operating combination of the transmission elements provides four forward speeds and one reverse speed.

The front planetary gear set FP is a single pinion type, and includes a first sun gear S3. 1st pinion P1. The rear planetary gear set RP includes a first ring gear R1, and the rear planetary gear set RP is of a double pinion type;
Second sun gear S2. First pinion (second inner pinion) R4, second outer pinion P2. 2nd ring gear R2
The first pinion P1 and the second pinion P2 mesh with each other, the sun gear is divided into a first sun gear Sl and a second sun gear S2, and both planetary gear sets FP and RP are connected to a pinion that is integrally fixed. Have a carrier PC.

In other words, it has an improved Lavigneaux-type planetary gear set structure with a one-segment sun gear.

As shown in FIGS. 3 and 4, the first sun gear S1 is formed in a shaft-shaped first sun gear member S Ml,
The second sun gear S2 is a cylindrical shaft-shaped second sun gear member S&
The pinion carrier PC is formed integrally with the output shaft 0 inserted into the second sun gear member S&l□, and the first sun gear member S&l; They are arranged in series on the same axis.

In addition, in FIGS. 3 and 4, PQl and PO2 are the pins that support both pinions, R&ll is the first ring gear member,
R12 is a second ring gear member.

The coupling relationship between each rotating element (sun gear, ring gear, pinion carrier) of the gear train and each transmission element will be described below.

With respect to the input shaft I, the second ring gear R2 is connected to the first clutch C1, and the first ring gear R1 is connected to the second clutch C1.
2, the first sun gear sl can be coupled and released via a third clutch C3.

For case K, the second ring gear R2 is connected to the first brake B1, and the second sun gear s2 is connected to the second brake B2.
A second ring gear R2 is provided so as to be stationary and releasable via a first one-way clutch OWC.

As mentioned above, the pinion carrier PC is connected to the output shaft O.
It is connected to the.

Next, one effect will be explained.

First, the operating state of each transmission element is as shown in FIG. 2, where the ◯ mark indicates engagement or operation, and the x mark indicates non-operation.

(a) During DI continuous speed in the D (drive) range, if only the second clutch C2 is operated to connect the input shaft I and the first ring gear R1, the second ring gear R2 will be connected by the operation of the first one-way clutch OWC. While preventing rotation in the reverse direction, the input shaft ■→first ring gear R1-first pinion P1→pinion carrier Pc→
Power is then transmitted to the output shaft 0.

At this time, as a constraint condition, the second ring gear R2 is prevented from rotating in the reverse direction by the first one-way clutch OWC, so the second outer pinion P2 that meshes with the first pinion gear P1 moves in the forward direction along the second ring gear R2. One pinion P revolves in the direction of rotation 1. The pinion carrier PC supporting P2 is rotated at a reduced speed.

Therefore, from the output shaft O connected to the pinion carrier Pc, a l-speed gear position with a large reduction gear ratio is obtained.

For D22 speed, the second clutch C2 and the second brake B2 are operated to couple the input shaft ■ and the first ring gear R, and the second sun gear S2 is made stationary on the case K, so that the input shaft ■→the first ring gear Power is transmitted from R1 to first pinion P, from pinion carrier Pc to output shaft 0. At this time, as the constraint condition is that the second sun gear S2 is stationary due to the second brake B2, the first pinion P1 revolves in the normal rotation direction along the second sun gear S2, and the pinion that supports the first pinion P Rotate the carrier PC at a reduced speed.

Therefore, from the output shaft O connected to the pinion carrier PC, a second speed gear position having a smaller reduction gear ratio than the first speed can be obtained.

For D33 speed, the first clutch C1 and the second clutch C2 are actuated to connect the input shaft (■), the first ring gear R, and the second ring gear R2, and the input shaft I→first ring gear R, (second ring gear R, ) → 1st pinion pt (2nd
Power is transmitted from the outer pinion P2) to the pinion carrier Pc to the output shaft 0.

At this time, the first and second pinions p, ,p are connected to both ring gears R by input from the first and second ring gears R1 and R2.
,,R, revolve together in the normal rotation direction, so the pinion carrier PC rotates at the same rotation as the input shaft I.

Therefore, a three-speed gear position with a gear ratio of 1 is obtained from the output shaft O connected to the pinion carrier PC.

For D44 speed, first clutch C1 and second brake B2 are operated, input shaft I and second ring gear R2 are coupled, and second sun gear S2 is stationary on case K. Then, input shaft I → second ring gear R2 →2nd outer pinion P2→
Power is transmitted from the pinion carrier Pc to the output shaft O. At this time, since the second sun gear S2 is stationary by the second brake B2 as a constraint condition, the pinion carrier PC rotates at a gear ratio l, and the first pinion P1 and second outer pinion P2 that mesh with each other are connected to the second ring gear. The rotation input from R2 causes the pinion carrier PC, which revolves in the normal rotation direction along the second sun gear S2 and supports both pinion gears P, P2, to accelerate.

Therefore, from the output shaft 0 connected to the pinion carrier Pc, a 4-speed gear position is obtained by increasing the speed at a gear ratio of 1 or less.

In addition, in the engine braking region (engine braking region) where torque is input from the wheels via the output shaft 0, the first brake B is used instead of the first one-way clutch OWC, as shown in the engine braking region in Fig. 2. By activating the engine brake, the engine brake is activated to prevent idling.

Moreover, even if the first sun gear S1 is fixed to the case K instead of fixing the second sun gear S2 to the case K, the same operation will be achieved.

(b) In R (reverse) range In R range, the third clutch C1 and the first brake B,
When the input shaft I and the first sun gear Sl are coupled together and the second ring gear R2 is rested on the case K, the input shaft ■ → the first sun gear S1 → the first pinion P, → the pinion carrier Pc - the output shaft 0. power is transmitted. At this time, since the second ring gear R2 is stationary as a constraint condition, the first pinion P and the second outer pinion P2 that mesh with each other revolve in a decelerated state along the second ring gear R2 in the reverse direction.

Therefore, from the output shaft 0 connected to the pinion carrier Pc, a reverse gear position is obtained by the reduction gear ratio.

China mini, a = Z 9/ Z RF, β = Z s
/ Z RR (where z3: number of teeth of sun gear, ZRF: number of teeth of first ring gear R1, ztt*: number of teeth of second ring gear R2), the following Begear ratios are obtained at each gear stage.

ix = 1 + α i , = 1.000 1 a = 1-〇 As explained above, in the power train of the automatic transmission of the embodiment, while obtaining four forward speeds, the basic The Lavigneau type gear train is compact, the ring gear input is advantageous in terms of strength, and the sun gear is split into two, making it adaptable to FR vehicles (adapted to FF vehicles) despite having a pinion carrier Pc output. (of course possible) and simplification of the output extraction structure can be achieved at the same time.

Although the embodiment has been described above based on the drawings, the specific configuration is not limited to this embodiment, and even if there is a design change within the scope of the gist of the present invention, it is included in the present invention. .

For example, it is a well-known method to reduce shift shock while simplifying shift control. A fourth clutch C4 and a second one-way clutch 0WC2 may be provided, and as shown in the power train diagram of FIG. A brake B3 and a third one-way clutch OWC may also be provided.

(Effects of the Invention) As explained above, in the power train of the automatic transmission of the present invention, the planetary gear set is divided into a single pinion type first planetary gear set and a double pinion type second planetary gear set. The first pinion and the first inner pinion are integrated and mesh with the second outer pinion gear, and each planetary gear set has a first sun gear and a second sun gear separated from each other as a sun gear. The pinion carrier is coupled and integrated, and the second ring gear and the first ring gear are connected to the input shaft via the first and second clutches, and the second ring gear and the first ring gear are provided so as to be connectable and disengageable via the first and second clutches. In this case, the first sun gear or the second sun gear is provided to be stationary and releasable via a brake, and the second ring gear is provided to be prevented from rotating in one direction and rotatable in the other direction via a one-way clutch. , since the extraction part of the pinion carrier is connected to the output shaft, four forward speeds can be obtained, while the compactness of the Lavigneaux-type gear train and the ring gear input are achieved. The advantage in terms of strength is that the sun gear is divided into two parts, making it suitable for FR cars and FF cars despite the pinion carrier output.
The effect is that it is possible to simultaneously achieve adaptation to vehicles and simplification of the output extraction structure such that only two coaxial shafts are required.

[Brief explanation of the drawing]

FIG. 1 is a skeleton diagram showing the power train of an automatic transmission according to an embodiment of the present invention, FIG. 2 is an operation diagram showing the operating state of each transmission element in the power train of the automatic transmission according to the embodiment, and FIG. FIG. 4 A-A showing the gear train of the embodiment! FIG. 4 is a sectional view of the gear train of the embodiment
5 is a skeleton diagram showing the power train of another embodiment, and FIG. 6 is a skeleton diagram showing the power train of another embodiment. -...Powertrain of automatic transmission ■...Input shaft O...Output shaft K...Case FP-...Front planetary gear set (1st planetary gear set) RP-...Rear planetary - Gear set (second planetary gear set) S,...first sun gear P, -first pinion R, -...first ring gear B2...second sun gear R2...second outer pinion R2...・Second ring gear PC...Pinion carrier C1...First clutch (first clutch) C2...
Second clutch (second clutch) C3...Third clutch B...First brake B2...Second brake (brake) OWC+...First one-way clutch (one-way clutch)

Claims (1)

[Claims] 1) A first sun gear, a second ring gear, a first pinion that meshes with these, and a first pinion that rotatably supports the first sun gear and the second ring gear.
A single pinion type first planetary gear set having a pinion carrier, a second sun gear, a second inner pinion that meshes with it, a second ring gear and a second inner pinion, and a second outer pinion that meshes with both of the second ring gear. Two planetary gear sets, a double pinion type second planetary gear set having a second pinion carrier that rotatably supports both the inner and outer pinions, are arranged between the input shaft and the output shaft, and are used for clutches, brakes, etc. In the power train of an automatic transmission that obtains multiple gear stages by operating combinations of transmission elements, the first pinion and the second inner pinion are integrated, and the sun gear is used as the first sun gear and the second sun gear. The first and second pinion carriers of both planetary gear sets are connected to each other and integrated, and taken out from the divided portion of both sun gears,
For the input shaft, the second ring gear and the first ring gear are connected and disengaged via first and second clutches, and for the case, the first sun gear or the second sun gear is connected via a brake. The second ring gear is provided so as to be stationary and releasable, and the second ring gear is prevented from rotating in one direction and rotatable in the other direction via a one-way clutch, and the take-out portion of the pinion carrier is connected to the output shaft. automatic transmission powertrain.