JP2001349395A - Automatic transmission mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multistage transmission mechanism capable of setting appropriate gear ratio of the whole transmission mechanism and a reduction gear ratio step of each gear stage so as to satisfy demand as an automobile and attaining miniaturization. SOLUTION: This automatic transmission mechanism comprises one simple planetary gear DP and a pair of planetary gears PU, and ring gears R1 and R2 are integrally connected to each other and a carrier CR2 and a ring gear R3 are integrally connected. First to sixth gears and reverse gear shown in the velocity diagram can be obtained by motion of each of clutches C-1 to C-3 and brake B-1 to B-2 shown in the motion diagram. Appropriate gear ratio width and reduction gear ratio step are obtained by setting as shown in the figure of the gear ratio λ.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission mechanism mounted on a motor vehicle and, more particularly, to an automatic transmission mechanism (gear train) capable of performing a multi-speed shift such as a forward fifth speed and a sixth speed.

[0002]

2. Description of the Related Art In recent years, automobiles have been required to be downsized, have high quietness, improve fuel efficiency, and have high output and efficiency, and accordingly, automatic transmissions have also been required to have multiple stages and downsizing. I have.

Conventionally, in order to increase the number of stages of an automatic transmission, a combination of a three-speed main transmission mechanism and a second-speed or third-speed auxiliary transmission mechanism obtains five or more forward gears. The main transmission mechanism and the auxiliary transmission mechanism are arranged on different shafts and are interlocked by a counter gear, thereby achieving compactness in the axial direction.

[0004]

However, the combination of the main transmission mechanism and the auxiliary transmission mechanism can achieve the above-mentioned required vehicle performance, even if a multi-speed transmission such as five forward speeds can be obtained. On the other hand, it is difficult to appropriately set the gear ratio of the entire transmission and the gear ratio step of each gear, and it is also difficult to satisfy sufficient compactness.

Accordingly, the present invention provides a multi-stage system which can set a proper gear ratio of the entire speed change mechanism and a gear ratio step of each speed stage in order to satisfy the requirements as an automobile, and can also improve compactness. It is an object to provide a transmission mechanism.

[0006]

According to a first aspect of the present invention, there is provided an input-side planetary gear having an element connected to an input section (IN) and having at least one gear ratio. (DP) and an element coupled to the output (OUT) and having a ratio of at least two teeth,
A coupling planetary gear unit (PU) having a plurality of shift speeds by engaging and disengaging a friction engagement element, wherein the input-side planetary gear (DP) includes an element (CR1) coupled to the input section (IN), and a rotation. Is fixed (S1)
And an element (R1) that outputs rotation to the connection planetary gear unit (PU), and the element (R1) that outputs rotation is connected to a first friction engagement element (for example, C- in FIG. 1).
2. According to C-3) of FIG. 2, the output can be freely output to the connected planetary gear unit (PU), and the connected planetary gear unit (PU) is connected to the input-side planetary gear (D).
P), the first ring gear (R2) connected to the first brake (B-2) and the second clutch (C-C) connected to the input portion (IN).
1) and a second sun gear (S2) connected to the first sun gear (S2).
3) and a third clutch (C in FIG. 1) is connected to the input section (IN).
-3, a first carrier (CR2) connected via a second carrier (C-2) in FIG. 2, and a second brake (B-1 in FIG. 1 and B in FIG. 2) connected to the first carrier (CR2). -4) a second ring gear (R3) connected to the output section (OUT)
And a second carrier (CR3) connected to the first and second clutches, and at least a fifth forward speed and a first reverse speed are achieved by switching the first friction engagement element, the second and third clutches, and the first and second brakes. An automatic transmission mechanism characterized in that:

According to a second aspect of the present invention, the first frictional engagement element is provided between the input section (IN) and an element (CR1) connected to the input section (IN) or the connection planetary gear unit. (PU) and the element for outputting the rotation (R
1) and a first clutch (C-C in FIG. 1) which is capable of outputting to the connected planetary gear unit (PU) freely.
2. The automatic transmission mechanism according to claim 1, which is C-3) in FIG.

According to a third aspect of the present invention (see FIG. 2), a third brake (B-1) for selectively fixing the element (S1) to which the rotation is fixed, and the third brake (B-). 1)
One-way clutch (F-1) disposed in parallel with
A second one-way clutch (F-2) arranged to be connected to an element (CR1) connected to the input section (IN) and capable of being engaged by a fourth brake (B-3); The automatic transmission mechanism according to claim 1, further comprising a third one-way clutch (F-3) disposed in parallel with the second brake (B-4).

According to a fourth aspect of the present invention (see FIG. 2), a multiple shaft is provided coaxially on a central axis, and the first one-way clutch (F-1) and the first one-way clutch (F-1) are provided on different axes of the multiple shaft. The automatic transmission mechanism according to claim 3, wherein an inner race of the second one-way clutch (F-2) is provided.

According to a fifth aspect of the present invention (see FIG. 2), the second ring gear (R3) is formed integrally with an inner race of the third one-way clutch (F-3). Or the automatic transmission mechanism according to 4.

According to a sixth aspect of the present invention (see FIG. 2), the second one-way clutch (F-2) and the first one-way clutch (F-1) are shifted to a relatively low speed (for example, the second speed). The automatic transmission mechanism according to any one of claims 3 to 5, wherein the automatic transmission mechanism is engaged with the first ring gear (R2) to restrict rotation in one direction.

According to a seventh aspect of the present invention (see FIG. 2), the second one-way clutch (F-2) is disposed on the inner diameter side of the first one-way clutch (F-1).
An automatic transmission mechanism according to claim 6.

The reference numerals in parentheses are for the purpose of comparison with the drawings, but are for convenience of understanding of the invention. It has no effect.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. In each figure, a skeleton diagram of the gear train, an operation table, a gear ratio, and a speed diagram thereof are shown, which schematically show a skeleton portion of each automatic transmission. It is needless to say that a one-way clutch or the like may be arranged in accordance with the speed ratio, and the speed diagram is not necessarily described on a scale corresponding to the gear ratio. Also, in each automatic transmission mechanism, a torque converter is disposed between the input side and the engine, and a differential device, a counter gear, a simple transmission, and the like are disposed on the output side,
The entirety constitutes a vehicle automatic transmission.

In the automatic transmission mechanism shown in FIG. 1, an input side, that is, a sun gear S1 of a dual planetary gear DP on the left side of the skeleton diagram is fixed to a gear case, and an input shaft serving as an input portion (hereinafter simply referred to as an "input shaft"). IN, the carrier CR1 is connected, and the input shaft is connected to the sun gears S2, S3 via the clutch C-1 and the carrier CR via the clutch C-3.
2 and a ring gear R3 connected to the brake B-1. The ring gear R1 is provided with a clutch C-2.
Through an output shaft (hereinafter simply referred to as “output shaft”) that is connected to a ring gear R2 connected to the brake B2 and is an output unit.
And ) Is connected to the carrier CR3.

As can be seen from the operation table and the speed diagram, the automatic transmission mechanism shown in FIG. 1 rotates the input shaft at the first speed and the second speed by rotating the output side with two simple planetary gear units (connected planetary gear units). ) PU sun gear S
The rotation input to S2 and S3 and reduced by the ring gear R1 of the input-side simple planetary gear at the third and fifth speeds is input to the ring gear R2 via the clutch C-2.

Here, the ratio of the number of teeth is λ1 (S
1 / R1) = 0.55, λ2 (S2 / R2) = 0.4
By setting 0, .lambda.3 (S3 / R3) = 0.40, the gear ratio and the gear ratio step and the ratio ratio 4.8 of FIG.
75 is obtained.

Next, the automatic transmission mechanism shown in FIG. 2 will be described in detail with reference to the drawings. The automatic transmission mechanism shown in FIG. 2 is a partial modification of the automatic transmission mechanism shown in FIG.

As shown in the skeleton diagram of FIG. 2, in the automatic transmission mechanism, the input-side planetary gear DP is composed of a dual planetary gear, and the connected planetary gear unit PU
Consists of two simple planetary gear units. The input-side planetary gear DP includes a sun gear (an element for which rotation is fixed) S1, a carrier (an element connected to the input unit) CR1, and a ring gear (an element for outputting rotation) R1.
And The carrier CR1 is connected to the input shaft (input portion) IN via a (first) clutch C-3, and can be freely engaged by a (fourth) brake B-3 (second) one-way clutch F -2 is provided to restrict rotation in one direction. The sun gear S1 is connected to the (third) brake B-1 so that the rotation is freely fixed, and the rotation in one direction is regulated by the (first) one-way clutch F-1 arranged in parallel. . The ring gear R1 is
It is connected to the (first) ring gear R2 of the connection planetary gear unit PU.

The connected planetary gear PU has one planetary gear having a ring gear R2 connected to the ring gear R1, a (first) sun gear S2, and a (first) carrier CR2, and is connected to the carrier CR2 (second). It comprises a ring gear R3, one planetary gear having a (second) sun gear S3 connected to the sun gear S2, and a (second) carrier CR3. The ring gear R2 is connected to the ring gear R1,
(1) It is connected to the brake B-2 and can be fixed freely. The sun gear S2 and the sun gear S3 are connected to the input shaft IN via a (second) clutch C-1 and are freely engageable with the input shaft IN. The carrier CR2 and the ring gear R3 are connected to the input shaft IN via a (third) clutch C-2 so as to be freely engageable with the input shaft IN. The ring gear R3 (and the carrier CR2)
Is connected to the (second) brake B-4 so as to be freely fixed, and in one direction by engagement of a (first) one-way clutch F-3 arranged in parallel with the brake B-4. Rotation is regulated. And the carrier CR3,
It is connected to an output shaft (output unit) OUT.

When the automatic transmission mechanism is actually constructed, the inner race of the one-way clutch F-3 can be integrally formed with, for example, a hub portion extending from the ring gear R3, so that the inner race can be integrally processed. For example, it is possible to eliminate the necessity of welding another member, for example, to reduce man-hours, and to reduce the cost of the automatic transmission mechanism. Further, when the present automatic transmission mechanism is actually configured, a multiple shaft arranged coaxially on the central axis is provided, and the first one-way clutch F-
1 and the inner race of the one-way clutch F-2 are provided, respectively, so that the multiple shaft is affected by so-called "play" as compared with a case where the inner race is provided on a hub portion extended from a carrier, for example. Since it is a difficult part, durability can be improved.

Next, the operation of the automatic transmission mechanism will be described with reference to the operation table and the speed diagram of FIG. The ratio of the number of teeth is λ1 (S1 / R1) = 0.480, λ2 (S2 /
R2) = 0.480, λ3 (S3 / R3) = 0.38
0, respectively.

In the first speed, the clutch C-1 is engaged to input the input rotation from the input shaft IN to the sun gear S3 (and the sun gear S2). On the other hand, the one-way clutch F-3 is engaged to fix the rotation of the ring gear R3 (and the carrier CR2) in one direction. Then, the fixed rotation of the ring gear R3 and the input rotation of the sun gear S3 are input to the carrier CR3, and the normal rotation of the gear ratio 3.632 is output. During engine braking, the brake B-4 is locked, the ring gear R3 (and the carrier CR2) is fixed, and the state of the first speed is maintained.

In the second speed, the brake B-3 is locked, the one-way clutch F-2 is engaged, the rotation of the carrier CR1 in one direction is fixed, and the one-way clutch F-1 is locked.
To fix the rotation in one direction of the sun gear S1 (the same direction as the rotation direction in which the one-way clutch F-2 is fixed via the carrier CR1 and the sun gear S1), that is, the one-way clutches F-1 and F-2. , The rotation of the ring gear R2 in one direction is fixed via the ring gear R1. On the other hand, the clutch C-1 is engaged to input the input rotation from the input shaft IN to the sun gear S2 and the sun gear S3.
The fixed rotation of the ring gear R2 and the input rotation of the sun gear S2 output the reduced rotation to the carrier CR2, and the reduced rotation input to the ring gear R3 via the carrier CR2 and the input rotation of the sun gear S3 are input to the carrier CR3. , A forward rotation with a gear ratio of 1.959. In addition,
At the time of engine braking, the brake B-2 is locked to fix the ring gear R2, and the state of the second speed is maintained.

At the third speed, the clutch C-3 is engaged, the input rotation from the input shaft IN is input to the carrier CR1, and the one-way clutch F-1 is engaged to fix the sun gear S1 in one direction. I do. And, the fixed sun gear S1
And the input rotation of the carrier CR1, the ring gear R1
The deceleration rotation is input to the ring gear R2 via the. on the other hand,
With the clutch C-1 engaged, the sun gear S2 and the sun gear S
3 inputs the input rotation from the input shaft IN. The reduced rotation of the ring gear R2 and the input rotation of the sun gear S2 output a reduced rotation to the carrier CR2 (a reduced rotation slightly larger than the reduced rotation of the ring gear R2).
The deceleration rotation input to the ring gear R3 via the R2 and the input rotation of the sun gear S3 are input to the carrier CR3, and a normal rotation with a gear ratio of 1.307 is output. At the time of engine braking, the brake B-1 is locked to release the sun gear S1.
And maintain the third speed.

In the fourth speed, the clutch C-2 is engaged to input the input rotation from the input shaft IN to the carrier CR2, and the clutch C-1 is engaged to engage the sun gears S2 and S3 from the input shaft IN. Enter the input rotation. As a result, the carrier CR2 and the ring gear R3 and the sun gears S2 and S3 have the same forward rotation, that is, the direct rotation is changed to the carrier C2.
Input to R3, and output normal rotation with a gear ratio of 1.000.

In the fifth speed, the clutch C-3 is engaged to input the input rotation from the input shaft IN to the carrier CR1, and the brake B-1 is locked to fix the rotation of the sun gear S1.
Then, the fixed sun gear S1 and the input rotation of the carrier CR1 cause the ring gear R1 via the ring gear R1.
Input the deceleration rotation to 2. On the other hand, the clutch C-2 is engaged to input the input rotation from the input shaft IN to the carrier CR2. Then, the reduced rotation of the ring gear R2 and the carrier C
With the input rotation of R2, an increased rotation is output to sun gear S2, and the input rotation input to ring gear R3 via carrier CR2 and the increased rotation input to sun gear S3 via sun gear S2 are input to carrier CR3. Then, a forward rotation with a gear ratio of 0.784 is output.

At the sixth speed, the brake B-2 is locked to fix the ring gear R2. On the other hand, the clutch C-2 is engaged to input the input rotation from the input shaft IN to the carrier CR2. Then, the fixed rotation of the ring gear R2 and the input rotation of the carrier CR2 output a speed-up rotation to the sun gear S2, and the input rotation input to the ring gear R3 via the carrier CR2 and the input rotation to the sun gear S3 via the sun gear S2. The speed-up rotation is input to the carrier CR3, and the normal rotation with a gear ratio of 0.635 is output.

In reverse, the one-way clutch F-1 is engaged to fix rotation of the sun gear S1 in one direction,
The clutch C-3 is engaged to input the input rotation from the input shaft IN to the carrier CR1. Then, by the fixed rotation of the sun gear S1 and the input rotation of the carrier CR1, the reduced rotation is input to the ring gear R2 via the ring gear R1.
On the other hand, the brake B-4 is locked to fix the carrier CR2 and the ring gear R3. The sun gear S is formed by the reduced rotation of the ring gear R2 and the fixed carrier CR2.
2, the reverse rotation input to the sun gear S3 via the fixed ring gear R3 and the sun gear S2 is input to the carrier CR3, and the reverse rotation with a gear ratio of 3.552 is output.

As described above, the automatic transmission mechanism shown in FIG. 2 can obtain an appropriate gear ratio, a gear ratio step, and a gear ratio width of 4.632 for the first to fifth to sixth speeds.
Coupled with the possibility of high-speed or six-speed multi-speed shifting,
Improvements in fuel economy can also be made possible. In addition, the present automatic transmission mechanism performs the speed change in the form of the one-way clutches F-1, F-2, and F-3 in the first to third speeds and the reverse speed, so that, for example, the clutch or the brake is re-engaged ( (Shift), the shift can be performed smoothly.

Since the above-mentioned automatic transmission mechanism has the above-described configuration, it can be configured by an input-side planetary gear composed of a dual planetary gear and a connected planetary gear unit composed of two simple planetary gears. It is possible to obtain an automatic transmission mechanism that can be improved. In addition, the number of clutches is three and the number of brakes is two (see FIG. 1). A one-way clutch is provided to facilitate shifting, while the number of clutches is three and the number of brakes is four. Since the number of components and the number of one-way clutches are three (see FIG. 2), the automatic transmission can achieve at least the fifth forward speed and the first reverse speed with a small number of parts. With the reduction in the number of parts, the automatic transmission mechanism has been made more compact,
And so on.

The one-way clutch F-2 is engaged with the one-way clutch F-1 at a relatively low speed, ie, at the second speed. However, at the second speed having a large torque capacity, the one-way clutches F-1 and F-2 are engaged. -2, the two one-way clutches, particularly the one-way clutch F-2, can be made relatively small. Thus, the automatic transmission mechanism can be made compact. Furthermore,
When the present automatic transmission mechanism is actually configured, the one-way clutch F-2 that can be configured to be relatively small can be provided on the inner diameter side of the one-way clutch F-1, that is, a so-called double structure, so that it is efficient. A simple arrangement structure can be made possible, and the automatic transmission mechanism can be made compact.

The first frictional engagement element (C-2 in FIG. 1,
C-3) of FIG.
A brake that disconnects and connects / disconnects the output to the connected planetary gear in a form provided on the input side or output side of the input-side planetary gear DP, but makes the element (S1) whose rotation is fixed freely rotatable. That is, in the input-side planetary gear DP, the input from the input shaft IN is always in the connected state, and the reverse input from the connected planetary gear UP is cut off by the free rotation state of the element to which the rotation is fixed. Of the input side planetary gear DP and the connection planetary gear UP
May be connected.

[0034]

According to the first aspect of the present invention, the gear ratio width of the speed change mechanism for achieving at least the fifth forward speed and the first reverse speed and the gear ratio steps of each shift speed are determined by the overall performance of the gear train. Can be set to an appropriate value that matches the requirements of the above, while the input-side planetary gear composed of a dual planetary gear
Since it is composed of a connected planetary gear unit composed of two simple planetary gears, it is possible to obtain an automatic transmission mechanism capable of downsizing, improving vehicle mountability, and the like. Further, since the number of clutches is three and the number of brakes is two, which is relatively small, an automatic transmission that achieves at least five forward speeds and one reverse speed with a small number of parts can be configured. With the reduction in the number of parts, it is possible to reduce the size of the automatic transmission mechanism and reduce the cost by reducing the number of parts.

According to the second aspect of the present invention, the first frictional engagement element is interposed between the input portion and the element connected to the input portion, or between the element outputting rotation and the connection planetary gear unit. As a result, since the first clutch allows the output to be freely output to the connected planetary gear unit, the rotation output by the input-side planetary gear can be freely engaged with the connected planetary gear unit.

According to the third aspect of the present invention, the third brake for selectively fixing the element whose rotation is fixed,
A first one-way clutch disposed in parallel with the brake, a second one-way clutch disposed in connection with an element coupled to the input portion and capable of being engaged by a fourth brake, and disposed in parallel with the second brake; And a third one-way clutch provided, so that the shift performed by switching the first and second brakes can be performed by the first, second and third one-way clutches, and these shifts can be performed smoothly. can do. In addition, while a one-way clutch is provided to facilitate shifting, a relatively small number of three clutches, four brakes, and three one-way clutches is used. It is possible to configure an automatic transmission that achieves at least five forward speeds and one reverse speed with a small number of parts. With the reduction in the number of parts, the automatic transmission mechanism can be made more compact, and the cost can be reduced by reducing the number of parts. Can be made possible.

According to the fourth aspect of the present invention, multiple shafts are provided coaxially on the central axis, and the inner races of the first one-way clutch and the second one-way clutch are provided on different axes of the multiple shafts. Therefore, when the present automatic transmission mechanism is actually configured, since the multiple shaft is a portion that is hardly affected by backlash, the durability of the automatic transmission mechanism can be improved.

According to the fifth aspect of the present invention, since the second ring gear integrally forms the inner race of the third one-way clutch, when the automatic transmission mechanism is actually constructed, the second ring gear and the second ring gear are connected to each other. The third one-way clutch can be integrated with the inner race to eliminate the need to weld another member, thereby reducing man-hours and thereby reducing the cost of the automatic transmission mechanism. It can be.

According to the sixth aspect of the present invention, the second one-way clutch is engaged with the first one-way clutch at a relatively low speed, and regulates the rotation of the first ring gear in one direction. In a relatively low-speed stage having a large capacity, the first and second one-way clutches can be divided to carry torque, and the two one-way clutches, in particular, the second one-way clutch can be configured to be relatively small. it can. Thus, the automatic transmission mechanism can be made compact.

According to the present invention, when the automatic transmission mechanism is actually constructed, the second one-way clutch, which can be made relatively small, is disposed on the inner diameter side of the first one-way clutch. Since it is possible to have a double structure, an efficient arrangement structure can be made possible, and the automatic transmission mechanism can be made compact.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention, showing a skeleton diagram, a speed diagram, an operation table, and a gear ratio of an automatic transmission mechanism.

FIG. 2 is a view showing another embodiment of the present invention, showing a skeleton diagram, a speed diagram, an operation table, and a gear ratio of the automatic transmission mechanism.

[Explanation of symbols]

DP: input side planetary gear PU: connected planetary gear unit IN: input section OUT: output section CR1: element connected to the input section S1: element for fixing rotation R1: element for outputting rotation S2 ... First sun gear S3 Second sun gear CR2 First carrier CR3 Second carrier R2 First ring gear R3 Second ring gear B-2 First brake B-1 in FIG. 1, FIG. B-4 in the second brake B-1 in FIG. 2... Third brake B-3 in FIG. 2... Fourth brake C-2 in FIG. 1 and C-3 in FIG. Coupling element (first clutch) C-1 ... second clutch C-3 in FIG. 1, C-2 in FIG. 2 ... third clutch F-1 ... first one-way clutch F-2 ... second one-way Clutch F-3: Third one-way clutch

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kazuhisa Ozaki 10 Takane, Fujiimachi, Anjo, Aichi Prefecture Inside Aisin AW Co., Ltd. (72) Inventor Yoichi Hayakawa 10 Takane, Fujiicho, Anjo, Aichi Prefecture Aishi F term in NW Corporation (reference) 3J028 EA25 EA30 EB08 EB13 EB31 EB37 FA06 FB03 FC16 FC20 FC25 FC62 GA02

Claims (7)

[Claims] An input-side planetary gear having an element connected to an input portion and having at least one gear ratio, and a friction member having an element connected to an output portion and having at least two gear ratios. A coupling planetary gear unit having a plurality of shift speeds by engaging and disengaging the coupling element; wherein the input-side planetary gear is configured to couple to the input unit, an element whose rotation is fixed, and to rotate the coupling planetary gear unit. An element that outputs the rotation, and the element that outputs the rotation is freely output to the connection planetary gear unit by a first frictional engagement element. The connection planetary gear unit is an element that outputs the rotation of the input-side planetary gear. Along with connecting
A first ring gear connected to a first brake, a first sun gear connected to the input portion via a second clutch, a second sun gear connected to the first sun gear, and a third clutch connected to the input portion; A first carrier connected to the first carrier, a second ring gear connected to the first carrier and connected to a second brake, and a second carrier connected to an output portion. The second and third clutches and the first,
An automatic transmission mechanism wherein at least five forward speeds and one reverse speed are achieved by switching the second brake. 2. The first frictional engagement element is provided between the input section and an element connected to the input section, or between the element outputting the rotation and the connection planetary gear unit.
The automatic transmission mechanism according to claim 1, wherein the automatic transmission mechanism is a first clutch that intervenes so as to output freely to the connected planetary gear unit. 3. A third brake for selectively fixing an element to which the rotation is fixed, a first one-way clutch disposed in parallel with the third brake, and an element connected to the input unit. 3. A second one-way clutch, which is disposed so as to be freely engageable by a fourth brake, and a third one-way clutch, which is disposed in parallel with the second brake. 4. Automatic transmission mechanism. 4. A multi-axis arranged coaxially on a central axis, and inner races of the first one-way clutch and the second one-way clutch are respectively arranged on different axes of the multi-axis. Item 4. The automatic transmission mechanism according to Item 3. 5. The automatic transmission mechanism according to claim 3, wherein the second ring gear integrally forms an inner race of the third one-way clutch. 6. The second one-way clutch engages with the first one-way clutch at a relatively low speed.
The automatic transmission mechanism according to claim 3, wherein rotation of the first ring gear in one direction is restricted. 7. The automatic transmission mechanism according to claim 6, wherein the second one-way clutch is disposed on an inner diameter side of the first one-way clutch.