KR20080017828A - 8 - shift gear train in an automatic transmission for vehicles - Google Patents

Abstract

An 8-shift gear train in an automatic transmission for vehicle is provided to enhance power transmission performance by combining a single planetary gear set, a complex planetary gear set, clutches, and brakes with each other. A first planetary gear set(PG1) is composed of a single planetary gear set and includes a first, second, and third operational elements. A first input path(T1) has a first speed-reducing ratio with respect to rotation of an input shaft through the first planetary gear set. A second input path(T2) has a second speed ratio of reverse rotation with respect to the rotation of the input shaft through the first planetary gear set. A second planetary gear set(PG2) is composed of a complex planetary gear set and includes first, second, third, and fourth operational elements. A third input path(T3) has a third speed ratio corresponding to the rotation of the input shaft and generates an output through the third operational element. A fourth input path(T4) has a fourth speed ratio corresponding to the rotation of the input shaft and generates an output through the third operational element. A clutch unit is independently inserted in the first, second, third, and fourth input paths in order to transmit rotation power selectively. A brake unit is disposed to operate the operational elements of the first and second planetary gear sets, as fixing elements.

Description

8-SHIFT GEAR TRAIN IN AN AUTOMATIC TRANSMISSION FOR VEHICLES}

1 shows a gear train of a first embodiment of an automatic transmission according to the invention;

2 is an operating element table of the gear train according to the first embodiment.

3 is a speed diagram of the gear train according to the first and second embodiments;

4 shows a gear train of a second embodiment of an automatic transmission according to the invention;

5 is a table of operating elements of the gear train according to the second embodiment.

The present invention relates to a gear train of an 8 speed automatic transmission for a vehicle.

In general, a multi-stage shifting mechanism of an automatic transmission is implemented by combining a plurality of planetary gearsets, and a gear train in which the plurality of planetary gearsets is combined receives a rotational power from a torque converter and shifts it to the output shaft. Will be

In such a sucrose transmission, the more gears that can be implemented, the more appropriate the gear ratio can be designed and the vehicle can be realized in terms of power performance and fuel efficiency. .

And even if the same shift stage is implemented, the durability, power transmission efficiency, size, etc. of the gear train vary according to the combination method of the planetary gear set, and thus, to invent a more robust, lossless, and more compact power train configuration Efforts are always going on.

In particular, unlike a manual transmission in which a shifting speed is more inconvenient for a driver, the automatic transmission shifts by controlling a gear train in accordance with a driving state. Efforts are being made to find a gear train configuration that can be implemented.

From this point of view, four-speed and five-speed automatic transmissions are the mainstream automatic transmissions currently in use, but recently six-speed automatic transmissions have been developed and applied to vehicles. Development is currently in progress.

Accordingly, the present inventors have proposed the present invention to meet the development of the automatic transmission as described above, and an object of the present invention is to convert one simple planetary gear set and one compound planetary gear set into a plurality of clutches and brakes. By combining the 8 forward speed and 1 reverse speed or 2 reverse speed, it is possible to provide the gear train of the 8-speed automatic transmission for the vehicle to improve the power transmission performance and reduce fuel consumption.

In order to realize the above object, the present invention comprises a first planetary gear set consisting of a simple planetary gear set and having first, second and third operating elements according to the arrangement order of each operating node on a speed line;

A first input path having a first speed ratio of deceleration to rotation of an input shaft through the first planetary gear set;

A second input path having a second speed ratio of reverse rotation with respect to rotation of an input shaft through the first planetary gear set;

A second planetary gear set consisting of a composite planetary gear set and having first, second, third and fourth operating elements according to the arrangement order of the respective operating elements on the speed line;

The third shaft has a third speed ratio equal to the rotation of the input shaft and is input to the second actuating element so as to perform a complementary action with the rotation selectively transmitted to the first actuating element through the first and second input paths. A third input path for outputting through a third operating element;

 A fourth speed ratio equal to the rotation of the input shaft is input to the fourth operating element and is complementary to the rotation selectively transmitted to the first operating element through the first and second input paths. A fourth input path through which the output is made through the third operating element;

Clutch means interposed independently on the 1,2,3,4 input paths to allow selective rotational power to be transmitted;

Provided is a gear train of an 8-speed automatic transmission for a vehicle, comprising brake means arranged so that some operating elements of the first and second planetary gear sets can operate as fixed elements.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in more detail.

 1 to 3 show a first embodiment of an automatic transmission for a vehicle according to the present invention, the gear train of the present invention comprises a first planetary gear set PG1 consisting of a double pinion planetary gear set, a ring gear and a planetary planet. The second planetary gear set PG, which consists of a composite planetary gearset of the lavender type sharing a carrier, is configured by combining a plurality of clutches and brakes.

The first planetary gear set PG1 which outputs in the state of deceleration and reverse rotation through two paths with respect to the rotation of the input shaft IS comprises a first operating element consisting of the sun gear S1 and a ring gear R1. A second operating element and a third operating element consisting of the planetary carrier PC1 are provided.

Accordingly, the first operating element {sun gear S1} is directly connected to the input shaft to always operate as an input element, and the second operating element {ring gear R1} is decelerated through the second clutch C2. Form a first input path T1 having a first speed ratio of < RTI ID = 0.0 > and < / RTI > the third actuating element {the planet carrier PC1} forms a second input path T2 having a second speed ratio of reverse rotation. do.

The second operating element {ring gear R1} is a first brake for deceleration and reverse rotation output through the second operating element {ring gear R1} and the third operating element {planetary carrier PC1}. It connects with the transmission housing H via B1, and the 3rd actuating element (the planet carrier PC1) is connected with the transmission housing H via the 2nd brake B2.

In the four operating elements constituting the second planetary gear set (PG2), the first operating element is a large diameter sun gear (S2), the second operating element to support two pinions (P1) (P2) in common Planetary carrier (PC2), the third operating element is a common ring gear (R2), the fourth operating element is made of a small diameter sun gear (S2), the two pinions (P2) (P3) is a long outer peripheral Composed of pinion (P1) and short pinion (P2), the short pinion (P2) is externally engaged with the small diameter sun gear (S3), and the long pinion (P1) is externally engaged with the large diameter pinion (S2) and at the same time the ring gear (R2) Inscribed in

In the second planetary gear set PG2, the first operating element (large diameter sun gear S2) always operates as an input element by the operation of the first and second input paths T1 and T2. The operating element {the planetary carrier PC2} is selectively supplied with rotational power from the input shaft IS via the third input path T3, and the third operating element {ring gear R2} is connected to the output gear OG. Connected to operate as an output element at all times, and the fourth operating element {narrow sun gear S3} selectively receives rotational power from the input shaft IS via the fourth input path T4.

Third and fourth clutches C3 and C4 are disposed on the third and fourth input paths T3 and T4 to selectively input the second operating element {the planetary carrier PC2}. Is connected to the transmission housing (H) via the third brake (B3) to operate as an optional fixing element.

The gear train made as described above shifts based on the vehicle load in the range of the shift stage according to the shift range selected by the driver under the control of the electronic control unit and the hydraulic system, not shown.

FIG. 2 shows the shift stage achieved by actuation (indicated by O in the figure) and actuation release of the clutch and brake indicated by the abbreviation in the figure, where (0) means irrelevant whether it is activated or deactivated, and FIG. The relationship between the speed change step achieved by engaging the clutch and the brake and the speed ratio of each operating element at that time is shown in the speed diagram.

Referring to the operation relationship of the automatic transmission of the present invention made as described above based on Figures 1 to 3 as follows.

In the shift diagram of FIG. 3, in the three operating nodes on the lever of the first planetary gear set PG1, the first operating node N1 is the first operating element (sun gear S1) and the second operating node N2. ) Is set to the second operating element (ring gear R1), and the third operating node N3 is set to the third operating element (planetary carrier PC1).

Further, in the four operating nodes on the lever of the second planetary gear set OPG2, the fourth operating node N4 is the first operating element (large diameter sun gear S2), and the fifth operating node N5 is the second operating node. Element {the planetary carrier PC2}, the sixth actuating node N6 is the third actuating element (ring gear R2), and the seventh actuating node N7 is the fourth actuating element (small diameter sun gear S3). Since the operation node setting is well known to those skilled in the art of the gear train, detailed description thereof will be omitted.

[1st speed forward]

In the forward 1 speed, the operation of the first and fourth clutches C1 and C4 and the first brake B1 is controlled.

Then, while the second operating node N2 is operated as a fixed element by the operation of the first brake B1, an output {second input path T2} is made through the third operating node N3. The reverse rotational input is made to the fourth operating node N4 by the operation of the first clutch C1, and at the same time, the seventh operating node N7 through the fourth input path T4 by the operation of the fourth clutch C4. The rotational power of the input shaft IS is input.

Accordingly, in the second planetary gear set PG2, the first shift line SP1 is formed, and as much as D1 connecting the first shift line SP1 and the sixth operation node N6, which is an output element, is output. As it is achieved, the speed of 1st forward is achieved.

[2 speed forward]

At the second forward speed, the first clutch C1 of the friction elements operated at the first forward speed is released, and the third brake B3 is controlled to operate.

Then, the first clutch C1 is operated in a state where an input is made to the seventh operating node N7 through the fourth input path T4 by the operation of the fourth clutch C4 as in the first forward speed. By the release, the input of the fourth operating node N4 is stopped, and the fifth operating node N5 is operated as the fixed element by the operation of the third brake B3.

Accordingly, in the second planetary gear set PG2, the second shift line SP2 is formed, and the output of D2 connecting the second shift line SP2 and the sixth operation node N6 as an output element is As it is achieved, the speed of the second forward is achieved.

In this forward two-speed shifting process, the operation of the first planetary gear set PG1 has no meaning, so the operation of the first brake B1 may be released.

[3 speed forward]

At the third forward speed, the operation of the third brake B3 among the friction elements operated at the second forward speed is released, and the first clutch C1 and the second brake B2 are operated and controlled.

Then, as in the second forward speed, the first clutch C1 and the first clutch C1 are input to the seventh operation node N7 through the fourth input path T4 by the operation of the fourth clutch C4. 2 The fourth operating node N4 is operated as a fixed element by the operation of the brake B2.

Accordingly, in the second planetary gear set PG2, the third shift line SP3 is formed, and the output of D3 connecting the third shift line SP3 and the sixth operation node N6 as an output element is As it is achieved, three speed shifts are achieved.

[4 forward speed]

At the 4th forward speed, the operation of the first clutch C1 of the friction elements operated at the 3rd forward speed is released, and the second clutch C2 is operated and controlled.

Then, as in the third forward speed, the second clutch C2 and the second clutch C2 are operated in the state where the input is made to the seventh operation node N7 through the fourth input path T4 by the operation of the fourth clutch C4. The deceleration state is input to the fourth operation node N4 through the first input path T1 by the operation of the second brake B2.

Accordingly, in the second planetary gear set PG2, the fourth shift line SP4 is formed, and as much as D4 connecting the fourth shift line SP4 and the sixth operation node N6, which is an output element, is output. As it is achieved, the speed of the fourth forward is achieved.

[5th forward]

At the 5th forward speed, the operation of the first clutch C1 of the friction elements operated at the 4th forward speed is released, and the third clutch C3 is operated and controlled.

Then, the input of the fourth operating node N4 through the first planetary gear set PG1 is released, and the fourth clutch C4 is operated to operate the fourth clutch through the fourth input path T4 as in the fourth forward speed. The input is made to the fifth working node N5 through the third input path T3 by the operation of the third clutch C3 in the state where the input is made to the seventh operating node N7.

Accordingly, the second planetary gear set PG2 is directly connected to form a fifth shift line SP5 and connects the fifth shift line SP5 and the sixth operation node N6 as an output element. As the output of D5 is achieved, the shifting speed of 5 forwards is achieved.

In this forward 5-speed shifting process, the operation of the first planetary gear set PG1 has no meaning. The operation of the second brake B2 may be released, but the operation may be controlled for the next shift stage.

[6th forward]

At the sixth forward speed, the fourth clutch C4 of the friction elements operated at the fifth forward speed is released, and the second clutch C2 is operated and controlled.

Then, the second clutch C2 and the second clutch C3 are input to the fifth operating node N5 through the third input path T3 by the operation of the third clutch C3 as in the fifth forward speed. The deceleration state is input to the fourth operating node N4 through the first input path T1 by the operation of the second brake B2.

Accordingly, in the second planetary gear set PG2, the sixth shift line SP6 is formed, and the output of D6 connecting the sixth shift line SP6 and the sixth operation node N6 as an output element is As it is achieved, the sixth forward speed is achieved.

[7th forward]

At the seventh forward speed, the operation of the second clutch C2 among the friction elements operated at the sixth forward speed is released, and the first clutch C1 is operated and controlled.

Then, as in the sixth forward speed, the first clutch C1 and the first clutch C3 are input to the fifth operating node N5 through the third input path T3 by the operation of the third clutch C3. As the input through the second input path T2 is stopped by the operation of the brake b2, the fourth operating node N4 operates as the fixed element.

Accordingly, in the second planetary gear set PG2, the seventh shift line SP7 is formed, and the output of D7 connecting the seventh shift line SP7 and the sixth operation node N6 as an output element is As it is achieved, the seventh speed shift will be made.

[8th forward]

At the eighth forward speed, the second brake B2 of the friction elements operated at the seventh forward speed is released, and the first brake B1 is operated and controlled.

Then, the first clutch C1 and the first clutch C1 are input to the fifth operating node N5 through the third input path T3 by the operation of the third clutch C3 as in the forward seventh speed. The reverse rotation is input to the fourth operation node N4 through the second input path T2 by the operation of the first brake B1.

Accordingly, in the second planetary gear set PG2, an eighth shift line SP8 is formed, and the output of D8 connecting the seventh shift line SP8 and the sixth operation node N6 as an output element is As it is achieved, the eighth forward speed is achieved.

[1 speed reverse]

In the reverse 1 speed shift stage, the second clutch C2 and the second and third brakes B2 and B3 are operated and controlled.

Then, when the deceleration is input to the fourth operating node N4 through the first input path T1 by the operation of the second clutch C2 and the second brake B2, the operation of the third brake B3 is performed. The fifth operating node N5 is operated as the fixed element.

Accordingly, in the second planetary gear set PG2, the reverse first speed transmission line RS1 is formed, and as much as the SR1 connecting the reverse first speed transmission line RS1 and the sixth operation node N6, which is an output element. As the output is made, the reverse speed 1 is shifted.

According to the gear train according to the first embodiment of the present invention in which the shift is made as described above, as shown in FIG. 2, one friction element is deactivated at all shift stages except for the 2 → 3 shift, and at the same time By operating the friction element to control operation, shift control can be easily performed.

4 to 5 show a second embodiment of the present invention, in which the second embodiment is configured in the same manner as the first embodiment, but the first operating element (large diameter sun gear S2) of the second planetary gear set PG2. Is variably connected to the input shaft IS via the fifth clutch C5 and is connected to the transmission housing H via the fourth brake B4.

Accordingly, when the first operating element (large diameter sun gear S2) of the second planetary gear set PG2 is operated as a fixed element, the first clutch C1 and the second brake B2 are simultaneously operated in the first sealing example. It had to be operated, but in the second embodiment, only the operation of the fourth brake B4 is enabled.

In addition, the second clutch 2 may realize the second reverse speed due to the addition of the fifth clutch C5. In the second reverse speed, the fifth clutch C5 and the third brake B3 are operated and controlled.

Then, as shown in FIG. 3, the fifth brake node N6 is moved to the fixed element by the operation of the third brake B3 while the input is made to the fourth brake node N5 by the operation of the fifth clutch C3. It works.

Accordingly, in the second planetary gear set PG2, the reverse second speed transmission line RS2 is formed, and as much as the SR2 connecting the reverse second speed transmission line RS2 and the sixth operation node N6, which is an output element. As the output is made, the reverse speed 2 is shifted.

Although a preferred embodiment of the gear train of the present invention has been described above, the present invention is not limited to the above embodiment, and those skilled in the art can easily invent the present invention from the embodiment of the present invention. It includes all modifications to the extent deemed to be equivalent.

As described above, according to the present invention, by combining one simple planetary gear set and one compound planetary gear set with a plurality of clutches and brakes to implement the 8 forward speed and 1 reverse speed or 2 reverse speed, power transmission performance It is an invention that can improve the fuel efficiency and reduce.

Claims (10)

A first planetary gear set consisting of a simple planetary gear set and having first, second and third actuating elements according to the arrangement order of each operating node on the speed line; A first input path having a first speed ratio of deceleration to rotation of an input shaft through the first planetary gear set; A second input path having a second speed ratio of reverse rotation with respect to rotation of an input shaft through the first planetary gear set; A second planetary gear set consisting of a composite planetary gear set and having first, second, third and fourth operating elements according to the arrangement order of the respective operating elements on the speed line; The third shaft has a third speed ratio equal to the rotation of the input shaft and is input to the second actuating element so as to perform a complementary action with the rotation selectively transmitted to the first actuating element through the first and second input paths. A third input path for outputting through a third operating element;  A fourth speed ratio equal to the rotation of the input shaft is input to the fourth operating element and is complementary to the rotation selectively transmitted to the first operating element through the first and second input paths. A fourth input path for outputting through a third operating element; Clutch means interposed independently on the 1,2,3,4 input paths to allow selective rotational power to be transmitted; And a brake means arranged so that some of the operating elements of the first and second planetary gear sets can operate as fixed elements. 2. The planetary gear set of claim 1, wherein the first planetary gearset consists of a double pinion planetary gearset, wherein the first actuating element acts as an input element as a sun gear and the second actuating element acts as a stationary element as a ring gear. 2 is connected to the input path, the third operating element is a planetary carrier, the gear train of the 8-speed automatic transmission for a vehicle, characterized in that it is connected to the first input path at the same time as a fixed element. 2. The second actuating gear set according to claim 1, wherein the second planetary gear set includes a first actuating element composed of a large diameter sun gear, a long pinion engaged with the large diameter sun gear, and a planetary carrier supporting the short pinion engaged with the long pinion. A vehicular planetary gear set comprising a planetary gear set comprising a element, a third actuating element comprising a ring gear meshed to the long pinion, and a fourth actuating element comprising a small diameter sun gear meshed to the short pinion. Gear train with 8-speed automatic transmission. 2. The apparatus of claim 1, wherein the clutch means comprises: first and second clutches respectively disposed on the first and second input paths to independently transmit power to the first operating element of the second planetary gear set; Gears of an 8-speed automatic transmission for vehicles characterized in that the third and fourth clutches are disposed on the third and fourth input paths, respectively, and independently connect the input shafts to the second and fourth operating elements of the second planetary gear set. Train. 2. The brake system of claim 1, wherein the brake means comprises: a first brake disposed between the second actuating element of the first planetary gear set and the transmission housing; A second brake disposed between the third actuating element of the first planetary gear set and the transmission housing; And a third brake disposed between the second actuating element of the second planetary gearset and the transmission housing. The clutch of claim 4 or 5, wherein the first, fourth clutch and the first brake are operated at the first speed, the fourth clutch and the third brake are operated at the second speed, and the first, the fourth clutch and the third brake are operated at the third speed. The second brake is operated, the second and fourth clutches and the second brake are operated at the fourth speed, the third and fourth clutches are operated at the fifth speed, the second and third clutches and the second brake are operated at the sixth speed, The first and third clutches and the first brakes are operated at the seventh speed, and the first and third clutches and the first brakes are operated at the eighth speed. The gear train of claim 8, wherein a fifth input path is further formed between the input shaft and the first operating element of the second planetary gear set. 8. The gear train of claim 8, wherein the fourth brake is disposed on the fifth input path and the fourth brake is disposed on the fifth input path. A double pinion planetary gear set, comprising: a first planetary gear set having a sun gear having a first operating element, a ring gear having a second operating element, and a planet carrier having a third operating element; A planet type planetary gear set which shares a planetary carrier with a ring gear, wherein the large diameter sun gear is composed of a first operating element, the planetary carrier is a second operating element, the ring gear is a third operating element, and the small diameter sun gear is a fourth operating element. Combine the second planetary gear set, The first planetary gear set includes the first planetary gear directly connected to an input shaft, and the third planetary element and the second actuating element of the first planetary gearset are interposed between the first and second clutches, respectively. And connecting the second and third operating elements to the transmission housing via the first and second brakes at the same time as the first and second operating elements of the gear set. The second planetary gear set connects the second and fourth actuating elements to the input shaft via the third and fourth clutches, respectively, and the second actuating element is connected to the transmission housing via the third brake and the third actuation. The gear train of an 8-speed automatic transmission for a vehicle characterized in that the element is connected to the output gear as an output element. A double pinion planetary gear set, comprising: a first planetary gear set having a sun gear having a first operating element, a ring gear having a second operating element, and a planet carrier having a third operating element; A planet type planetary gear set which shares a planetary carrier with a ring gear, wherein the large diameter sun gear is composed of a first operating element, the planetary carrier is a second operating element, the ring gear is a third operating element, and the small diameter sun gear is a fourth operating element. Combine the second planetary gear set, The first planetary gear set includes the first planetary gear directly connected to an input shaft, and the third planetary element and the second actuating element of the first planetary gearset are interposed between the first and second clutches, respectively. And connecting the second and third operating elements to the transmission housing via the first and second brakes at the same time as the first and second operating elements of the gear set. The second planetary gear set connects the second and fourth actuating elements to the input shaft via the third and fourth clutches, respectively, and the second actuating element is connected to the transmission housing via the third brake and the third actuation. The element is connected to the output gear as an output element, and the gear train of the 8-speed automatic transmission for a vehicle, characterized in that the first operating element is connected to the input shaft as a fifth clutch and is connected to the transmission housing via a fourth brake. .

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