JPH0646063B2 - Automatic transaxle - Google Patents

Description

Description: (a) Technical Field The present invention relates to an automatic transaxle.

(B) Prior Art As a conventional automatic transaxle, there is, for example, one disclosed in Japanese Unexamined Patent Publication No. 58-84248, “Drive device for automobile”. This drive device is provided with a main transmission of forward three speeds and an auxiliary transmission arranged on an axis parallel to the main transmission.
The main transmission and the sub transmission are connected by gears, and the rotational force from the main transmission is further changed by the sub transmission and input to the differential mechanism. The main transmission is an automatic 3-speed forward transmission that has a gear ratio of 1 at the highest speed,
The auxiliary transmission is a two-stage automatic transmission mechanism having a maximum transmission gear ratio of 1, and the gear ratio connecting the main transmission and the auxiliary transmission is an overdrive transmission ratio. That is, in this drive device, in order to obtain the overdrive gear ratio, the gear ratio of the gear that connects the main transmission and the auxiliary transmission is set as the overdrive gear ratio. With such a configuration, a forward four-speed transmission having an overdrive speed ratio can be obtained. However, in such a transmission, although it has a complicated structure in which the auxiliary transmission is provided, it is possible to obtain only the forward four-speed shift stage, and in order to improve the power performance and the fuel consumption rate. Is not always enough. Also, to obtain the overdrive speed ratio,
It is necessary to increase the diameter of the gear on the main transmission side of the gears that connect the main transmission and the auxiliary transmission, but it is not always possible to obtain the desired overdrive gear ratio due to the outer diameter of the main transmission. There is also a problem that you can not get. Japanese Patent Laid-Open No. 59-117943 discloses a combination of a forward four-speed automatic transmission mechanism having an overdrive stage with an additional overdrive mechanism arranged on a shaft arranged in parallel therewith. Has been done. However, there is a problem that this four-forward automatic transmission mechanism has an element that rotates at a very high speed when the overdrive stage is realized. That is, the overdrive stage is realized by one planetary gear, but in the case of this automatic transmission mechanism, the internal gear serves as input rotation and the pinion carrier serves as output rotation, so that the sun gear is at high speed (input rotation speed). Role 2.
It will rotate at 5 times). The presence of such a member that rotates at a high speed is not preferable in terms of strength and lubricating performance. Japanese Patent Laid-Open No. 57-195950 discloses a forward four-speed transmission using two planetary gear sets, three clutches, three brakes, and three one-way clutches in FIG. Has been done. But,
In this case as well, the overdrive stage is realized by one planetary gear set, but the sun gear serves as an input circuit, the carrier serves as output rotation, and the internal gear serves as free rotation. For this reason, the internal gear also rotates at about 2.5 times the input rotation, which causes the same problem as above and below.

(C) Object of the Invention The present invention has an object to obtain an automatic transaxle capable of obtaining a forward 5th speed with a simple structure and having no member rotating at a very high speed during overdrive. .

(D) Structure of the Invention According to the present invention, a forward four-speed automatic transmission mechanism having a simple structure in which a member that rotates at a very high speed at the time of overdrive does not exist, and an auxiliary transmission mechanism having a second speed stage are arranged in parallel. Thus, the above-mentioned object is achieved. That is, the automatic transaxle according to the present invention has the fluid transmission mechanism, the input shaft, the first automatic transmission mechanism, the intermediate output shaft, and the output gear that are arranged with the first axis as the central axis, and is parallel to the first axis. It has a counter gear arranged with the second axis as the central axis, a second automatic transmission mechanism, and a final pinion gear, and a differential mechanism is provided in the final gear that meshes with the final pinion gear. Two
It is composed of a set of planetary gear sets and is capable of changing the rotational force from the fluid transmission mechanism input from the input shaft to the fourth forward speed and the first reverse speed including the overdrive speed, and transmitting the same to the intermediate output shaft, The counter gear meshes with the output gear connected to the intermediate output shaft, and the second automatic transmission mechanism is premised on an automatic transaxle capable of shifting the rotational force from the counter gear to two stages and transmitting it to the final pininone gear. The speed ratio of the overdrive speed of the first automatic transmission is such that the pinion carrier of one planetary gear set is connected to the input shaft, the sun gear of one planetary gear set is fixed, and the internal gear of one planetary gear set is fixed. It is realized by connecting the Lugear to the intermediate output shaft, and in this state the pinion carrier of the other planetary gear set is connected to the intermediate output shaft,
The sun gear of the other planetary gear set is connected to the input shaft, and the internal gear of the other planetary gear set is automatically rotated.

As the first automatic transmission mechanism, for example, a first planetary gear set,
It has a second planetary gear set, a first clutch, a second clutch, a third clutch, a first brake, a second brake, and a one-way clutch, and the first planetary gear set includes a first sun gear and a first inner gear. The second planetary gear set is engaged with the second sun gear, the second internal gear, and both gears at the same time as the first gear and the first pinion carrier that supports the first pinion gear that meshes with both gears at the same time. And a second pinion carrier that supports the second pinion gear. And the first pinion carrier is the second
A first sun gear can be connected to the input shaft via a first clutch, a first pinion carrier can be connected to a second internal gear via a third clutch, and can be connected to the input shaft via a clutch. , The second sun gear is always connected to the input shaft, and the first internal gear and the second sun gear are
The pinion carrier is always connected to the intermediate output shaft,
The first brake can fix the first pinion carrier, the second brake can fix the first sun gear, and the one-way clutch allows rotation in the same direction as the input shaft of the first pinion carrier. However, it is possible to use one that is arranged in a direction that does not allow rotation in the opposite direction. Further, as the second automatic transmission mechanism, it is possible to select a mechanism having a speed increasing gear and a direct coupling speed or a mechanism having a speed reducing gear and a direct coupling speed.

(E) Embodiment Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 and 2 of the accompanying drawings.

(First Embodiment) FIG. 1 shows a first embodiment of the present invention. This automatic transaxle has a fluid transmission mechanism 10, a first automatic transmission mechanism 12, a second automatic transmission mechanism 14, and a differential mechanism 16. The fluid transmission mechanism 10 is composed of a torque converter with a lockup mechanism, and is arranged with a first axis 18 coaxial with a crankshaft of an engine (not shown) as a central axis. The rotational force from the engine is input to the fluid transmission mechanism 10, and the fluid transmission mechanism 10
Is output to the first automatic transmission mechanism 12 by the shaft 20. Similar to the fluid transmission mechanism 10, the first automatic transmission mechanism 12 arranged with the first axis 18 as the central axis is the first
Planetary gear set G ₁ , second planetary gear set G ₂ , first clutch C
₁ , second clutch C ₂ , third clutch C ₃ , first brake B ₁ , second brake B _2, and one-way clutch OW
As described later, the rotational force input from the shaft 20 can be changed to the fourth forward speed and the first reverse speed including the overdrive speed and output to the shaft 22 as will be described later. That is, the rotational state of each element of the planetary gear sets G ₁ and G ₂ is changed by operating the clutches C ₁ , C ₂ and C ₃ , the brake B ₁ (one-way clutch OWC) and B ₂ in various combinations. Therefore, the rotation speed of the shaft 22 with respect to the rotation speed of the shaft 20 can be variously changed. By operating the clutches C ₁ , C ₂ and C ₃ and the brakes B ₁ and B ₂ in the combinations shown in the table below,
4 forward speeds and 1 reverse speed can be obtained.

The circles in the above table indicate the clutches and brakes in operation, and α ₁ and α ₂ are the teeth of the sun gear with respect to the number of teeth of the internal gear of the first planetary gear set G ₁ and the second planetary gear set G ₂ , respectively. The gear ratio is the ratio of the rotational speed of the shaft 20 to the rotational speed of the shaft 22. The first automatic transmission mechanism 12 itself is, for example, Japanese Patent Laid-Open No. 58-15675.
It is similar to that shown in No. 7. On the shaft 22,
An output gear 24 is provided so as to rotate integrally therewith, and the output gear 24 meshes with a counter gear 28 arranged with a second axis 26 parallel to the first axis 18 as a central axis. The output gear 24 and the counter gear 28 are gears having the same number of teeth (note that this tooth number ratio can of course be changed as desired). The counter gear 28 has a shaft 30 rotating integrally therewith.
Is connected to the second automatic transmission mechanism 14. Second
The automatic transmission mechanism 14 has a third planetary gear set G ₃ , a fourth clutch C ₄ , and a third brake B ₃ . The third planetary gear set G ₃ includes a sun gear S ₃ and an internal gear R _3.
3 and a carrier PC ₃ that supports a pinion gear P ₃ that meshes with both gears S ₃ and R ₃ at the same time. The carrier PC ₃ is connected so as to rotate integrally with the above-mentioned shaft 30, and also the third internal gear R ₃
Are connected so as to rotate integrally with a shaft 32 arranged with the second axis 26 as the central axis. Also, the clutch C
₄ is a connection between the carrier PC ₃ and the internal gear R _3.
The disengagement can be controlled, and the third brake B ₃ can fix the sun gear S ₃ to the stationary portion as necessary. A final pinion gear 34 is provided on the shaft 32 so as to rotate integrally therewith, and the final pinion gear 34 is engaged with the final gear 36. The final gear 36 is integrally provided with the operating mechanism 16.

Next, the operation of this embodiment will be described. The rotational force input from the engine to this automatic transaxle is the fluid transmission mechanism 10, the shaft 20, the first automatic transmission mechanism 1.
2, shaft 22, output gear 24, counter gear 28, shaft 3
0, the second automatic transmission mechanism 14, the shaft 32, the final pinion gear 34, the final gear 36, and the operating mechanism 16 are transmitted in the order described above. In the meantime, the automatic transaxle is capable of shifting the forward 5 speed and the reverse 1 speed. In gear position and the reverse gear of the first to fourth speed, the fourth clutch C ₄ it is fastening and third brake B ₃ of the second automatic transmission mechanism 14 is released. As a result, the second automatic transmission mechanism 14 is in the direct connection state, that is, in the state of the gear ratio 1, and the rotation of the shaft 30 is transmitted to the shaft 32 as it is. Therefore, the shaft 32 is rotated by the operation of the first automatic transmission mechanism 12 in accordance with the gear ratios shown in the above table. In the case of the 5th speed, it operates as follows. That is, the first automatic transmission mechanism 12 has the second clutch C.
₂ and the second brake B ₂ are in a operated state with a gear ratio of 0.69, and the second automatic transmission mechanism 14 is in a state in which the fourth clutch C ₄ is released and the third brake B ₃ is engaged. ing. In this state, the shaft 32 rotates in a speed-increased state with respect to the shaft 30. For example, internal gear R ₃
If the gear ratio between the sun gear S ₃ and the sun gear S ₃ is 0.45, the gear ratio of the second automatic transmission mechanism 14 is 0.69. Therefore, the ratio of the rotation speed of the shaft 32 to the shaft 20 in this case is 0.69.
× 0.69 = 0.48. After all, the following gear ratio is obtained by the combination of the first automatic transmission mechanism 12 and the second automatic transmission mechanism 14.

1st speed = 3.22 2nd speed = 1.38 3rd speed = 1.00 4th speed = 0.69 5th speed = 0.48 Therefore, an automatic transaxle of 5th forward speed can be realized with a very simple structure. Obtainable. Moreover, in this case, the first automatic transmission mechanism 12 includes two planetary gear sets G ₁
And G ₂ alone are used to achieve the fourth forward speed, and the size of the entire automatic transaxle in the direction of the first axis 18 can be reduced. The first automatic speed change mechanism 12 itself has an overdrive speed change step, and the second automatic speed change mechanism 12 has a second speed change step.
Since the automatic transmission mechanism 14 multiplies the overdrive gear ratio, the fifth gear can be an overdrive gear having a very large speed increasing effect, and two overdrive gears having different gear ratios can be used. It can be a stepped automatic transaxle. Moreover, therefore, it is not necessary for the output gear 24 and the counter gear 28 to have an overdrive gear ratio. Therefore, it is not necessary to make the output gear 24 a large-diameter gear,
There is no need to increase the outer diameter dimension around the first axis 18. The gear ratio of this automatic transaxle can be changed by selecting the gear ratio between the internal gear of the planetary gear sets G ₁ , G ₂ and G ₃ and the sun gear. It can also be changed by changing the gear ratio of the output gear 24 and the counter gear 28. Therefore, the optimum gear ratio can be obtained according to the specifications of the vehicle and the engine. In addition,
In the first embodiment, the fourth clutch C ₄ is arranged so that the internal gear R ₃ and the carrier PC ₃ can be connected, but even if the internal gear R ₃ and the sun gear S ₃ are arranged so that they can be connected. Similar actions and effects can be obtained.

(Second Embodiment) FIG. 2 shows a second embodiment of the present invention. The second embodiment is different from the first embodiment shown in FIG. 1 in the second automatic transmission mechanism 1
Only 4'is different, and this part will be mainly described, and other parts will be denoted by the same reference numerals as those in FIG. 1 and description thereof will be omitted. The carrier PC ₃ of the second automatic speed change mechanism 14 ′ is connected to rotate integrally with the shaft 32, and the internal gear R ₃ is connected to rotate integrally with the shaft 30. Second automatic transmission mechanism 1
The 4'th fourth clutch C ₄ can control connection / disconnection between the internal gear R ₃ and the carrier PC _3, and the third brake B ₃ can fix the sun gear S ₃ to the stationary portion as necessary. Is. By the second automatic speed change mechanism 14 'with such a configuration, in the fourth state releasing the clutch C ₄ concluded and third brake B _3, a shaft 30 and the shaft 32 are rotated integrally, and On the contrary, when the fourth clutch C ₄ is released and the third brake B ₃ is engaged, the shaft 32 becomes the shaft 3
It will be decelerated with respect to 0 and will rotate. In the second embodiment, the first speed shift stage having a larger reduction ratio than the first speed of the first automatic transmission mechanism 12 can be obtained. That is, in the state in which the second automatic speed change mechanism 14 'and a fourth direct connection state by operating the clutch C _4, as the shaft 3 is the gear ratio by the first automatic shift mechanism 12 as in the first embodiment described above
2 to the 2nd to 5th speed stages of the automatic transaxle. At the first speed gear position of the entire automatic transaxle, the third clutch C ₃ and the first brake B ₁ of the first automatic speed change mechanism 12 are operated to set the gear ratio to 3.22 and the second automatic speed change mechanism. 14 'is the deceleration state by operating the third brake B _3. By doing so, the overall gear ratio is 3.22 ÷ 0.69 = 4.67. That is, the following gear ratio is obtained in the second embodiment.

1st speed = 4.67 2nd speed = 3.22 3rd speed = 1.38 4th speed = 1.00 5th speed = 0.69 Therefore, in this second embodiment as well, the advancement of the simple structure 5
A fast automatic transaxle can be obtained, and the same effects as those of the first embodiment can be obtained. Incidentally, also in the second embodiment, the fourth clutch C
No. ₄ may be arranged such that the internal gear R ₃ and the sun gear S ₃ can be connected to each other.

In the above embodiment, the overdrive stage of the first automatic transmission mechanism 12 is realized by operating the clutch C2 and the brake B2. In this case, the planetary gear set G is used.
The 1st pinion carrier becomes the input rotation, the sun gear is fixed, and the internal gear becomes the output rotation. On the other hand, the sun gear of the planetary gear set G2 is in input rotation, the pinion carrier is in output rotation, and the internal gear is in free rotation. The rotation of the internal gear in this case is about 1.6 times the input rotation. This is based on the above-mentioned JP-A-59.
It is significantly smaller than that disclosed in Japanese Patent Publication No. 117943. The reason for this is that in the present application, the planetary gear set G
The sun gear of No. 2 (the planetary gear set on the side not directly involved in the realization of the overdrive stage) is in the input rotation and the internal gear is in the free rotation state. This is because the internal gear of the planetary gear set that is not directly involved in the realization of the drive stage is the input rotation and the sun gear is in the free rotation state.

(F) Effects of the Invention As described above, according to the present invention, when the first automatic transmission mechanism and the second automatic transmission mechanism are combined to obtain the fifth forward speed, the first automatic transmission mechanism has the above-described configuration. Since such a structure is used, there is no member that rotates at extremely high speed during overdrive, which is advantageous in terms of durability performance, lubrication performance, and the like.

[Brief description of drawings]

FIG. 1 is a diagram showing an automatic transaxle which is a first embodiment of the present invention, and FIG. 2 is a diagram showing an automatic transaxle which is a second embodiment of the present invention. 10 ... Fluid transmission mechanism, 12 ... First automatic transmission mechanism, 1
4 ... Second automatic transmission mechanism, 16 ... Differential mechanism, 18 ...
1st axis, 20 ... Axis, 22 ... Axis, 24 ... Output gear, 26 ... Second axis, 28 ... Counter gear, 30 ...
… Axis, 32 …… Axis, 34 …… Final pinion gear,
36 ... Final gear.

Claims (2)

[Claims] 1. A fluid transmission mechanism arranged with a first axis as a central axis, an input shaft, a first automatic transmission mechanism, an intermediate output shaft, and an output gear, and a second axis parallel to the first axis. It has a counter gear arranged as an axis, a second automatic transmission mechanism, and a final pinion gear, and a differential mechanism is provided in the final gear that meshes with the final pinion gear. The first automatic transmission mechanism has two sets of planetary gears. In addition to being composed of a set, the rotational force from the fluid transmission mechanism that is input from the input shaft can be transmitted to the intermediate output shaft by changing the speed to the fourth forward speed and the first reverse speed including the overdrive speed stage. The second automatic transmission mechanism meshes with the output gear connected to the intermediate output shaft, and the second automatic transmission mechanism is capable of shifting the rotational force from the counter gear to two stages and transmitting the same to the final pinion gear. In transaxle transmission ratio of overdrive gear position of the first automatic transmission mechanism,
It is realized by connecting the pinion carrier of one planetary gear set to the input shaft, fixing the sun gear of one planetary gear set, and connecting the internal gear of one planetary gear set to the intermediate output shaft. The pinion carrier of the planetary gear set is connected to the intermediate output shaft, the sun gear of the other planetary gear set is connected to the input shaft, and the internal gear of the other planetary gear set is set to the free rotation state. Transaxle. 2. A first automatic transmission mechanism has a first planetary gear set, a second planetary gear set, a first clutch, a second clutch, a third clutch, a first brake, a second brake, and a one-way clutch. The first planetary gear set includes a first sun gear, a first internal gear, and a first pinion carrier that supports a first pinion gear that meshes with both gears at the same time, and a second planetary gear set. Includes a second sun gear, a second internal gear, and a second pinion carrier that supports a second pinion gear that meshes with both gears at the same time. The first pinion carrier is connectable to the input shaft via the second clutch, and the first sun gear is connectable to the input shaft via the first clutch.
The pinion carrier can also be connected to the second internal gear via the third clutch, the second sun gear is always connected to the input shaft, and the first internal gear and the second pinion carrier are always connected to the intermediate output shaft. The first brake can fix the first pinion carrier, the second brake can fix the first sun gear, and the one-way clutch can rotate in the same direction as the input shaft of the first pinion carrier. Claim 1 which is arranged in a direction in which rotation is permitted but rotation in the opposite direction is not permitted.
The automatic transaxle described in the item.