KR100308982B1 - Gear train for automatic transmission - Google Patents

Abstract

SUMMARY OF THE INVENTION An object of the present invention is to provide a gear train for an automatic transmission that realizes 5 forward speeds and 1 reverse speed with 3 planetary gears and 5 friction elements, while pursuing miniaturization and light weight, and improving power efficiency.

A gear train for an automatic transmission according to the present invention includes a first planetary gear having an element variably connected to an input shaft and an element for transmitting power to a transfer shaft;

A second planetary gear having an element variably connected to the input shaft and an element fixedly connected to two elements of the first planetary gear;

A third planetary gear having an element variably connected to the input shaft, an element for transmitting power to the transfer shaft, an element of a second planetary gear and an element fixed and variably connected to the transmission housing, respectively;

As described above, the first, second and third planetary gears fixed and variably connected are transferred to the input shaft to the forward 5 speed and the reverse 1 speed so as to be transferred to the transfer shaft. And first brakes for variably connecting the first, second, third, and fourth clutches to the input shaft, and the first, second, and third planetary gears to the transmission housing.

Description

Gear train for automatic transmission

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear train for an automatic transmission, and more particularly, to a gear train for an automatic transmission that achieves 5 forward speeds and 1 reverse speed while miniaturizing and reducing weight by efficiently combining a clutch, a brake, and a planetary gear.

In general, an automatic transmission is configured to automatically realize a multi-stage shift by controlling each element of a compound planetary gear, which is operated and deactivated by a hydraulic control system controlled by a transmission control unit (TCU), connected thereto. .

Such a gear train is commonly referred to as a combination of a planetary gear and a friction element to realize multi-stage shifting.

These gear trains are configured in various ways according to the target shift speed to be realized. In particular, the gear train which realizes 5 forward speeds and 1 reverse speed is composed of a combination of seven clutches and brakes and three planetary gears.

However, the gear train for the automatic transmission as described above has a disadvantage in that it increases in size and weight because many clutches and brakes are used, and because there are many non-operating friction elements that cause power loss.

Therefore, the present invention was created in order to avoid the above drawbacks, and the object of the present invention is to achieve miniaturization and light weight while achieving 5 forward speeds and 1 reverse speed with three planetary gears and five friction elements, and achieve power efficiency. It is to provide a gear train for an automatic transmission.

1 is a configuration diagram of a gear train for an automatic transmission according to the present invention.

2 is a friction element operation table for each shift stage of a gear train for an automatic transmission according to the present invention.

3 is a speed diagram showing the speed ratio of the D range 1,2 speeds of the gear train for an automatic transmission according to the present invention.

Fig. 4 is a speed diagram showing the speed ratio of the D range three speeds of the gear train for automatic transmission according to the present invention.

Fig. 5 is a speed diagram showing the speed ratio of the D range four speeds of the gear train for an automatic transmission according to the present invention.

FIG. 6 is a speed diagram showing a speed ratio of the D range 5 speed of the gear train for an automatic transmission according to the present invention. FIG.

Fig. 7 is a speed diagram showing a speed ratio at R range 1 speed of a gear train for an automatic transmission according to the present invention.

<Explanation of symbols for the main parts of the drawings>

1: input shaft, 3: transmission housing, 5: transfer shaft 7,9: first and second transfer drive gear, 11,13: first and second transfer driven gear, B1: first brake, C1, C2, C3, C4 1, 2, 3, 4 clutch, PG1, PG2, PG3: 1st, 2, 3 planetary gear

In order to realize this, the gear train for an automatic transmission according to the present invention includes three planetary gears fixed and variably connected to specific elements;

It includes five friction elements that selectively and variably connect the input shaft, each element of the planetary gear, and the transmission housing to control the 5 forward speeds and 1 reverse speed.

More specifically, the gear train for an automatic transmission according to the present invention includes a first planetary gear having an element variably connected to the input shaft and an element for transmitting power to the transfer shaft;

A second planetary gear having an element variably connected to the input shaft and an element fixedly connected to two elements of the first planetary gear;

A third planetary gear having an element variably connected to the input shaft, an element for transmitting power to the transfer shaft, an element of a second planetary gear and an element fixed and variably connected to the transmission housing, respectively;

As described above, the first, second and third planetary gears fixed and variably connected are transferred to the input shaft to the forward 5 speed and the reverse 1 speed so as to be transferred to the transfer shaft. And first brakes for variably connecting the first, second, third, and fourth clutches to the input shaft, and the specific elements of the first, second, and third planetary gears to the transmission housing.

In the gear train for an automatic transmission of the present invention configured as described above, the hydraulic control system selectively operates and releases the first, second, third, and fourth clutches and the first brake to control the first, second and third planetary gears. 5 forward speeds and 1 reverse speed are realized.

That is, the first clutch and the first brake in the D range 1 speed, the second clutch and the first brake in the D range 2 speed, the second and third clutches in the D range 3 speed, the first and third clutches in the D range 4 speed, and the 5th speed in the D range 5 speed. In the first, fourth clutch and R range 1 speed, the fourth clutch and the first brake are operated.

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

1 is a configuration diagram of a gear train for an automatic transmission according to the present invention, and is configured to realize five forward speeds and one reverse speed with three planetary gears and five friction elements.

That is, the gear train of the present embodiment is a variable connection of the first, second, third planetary gears (PG1, PG2, PG3), the specific elements of the first, second, third planetary gears (PG1, PG2, PG3) to the input shaft (1) The first, second, third, and fourth clutch (C1, C2, C3, C4), the first to variably connect the specific elements of the first, second, third planetary gears (PG1, PG2, PG3) to the transmission housing (3) The brake B1 is provided.

The first planetary gear PG1 has an element that is variably connected to the input shaft 1 and an element that transmits power to the transfer shaft 5.

The first planetary gear (PG1) is composed of a double pinion planetary gear, its sun gear (S1) and the carrier (Ca1) is variably connected to the input shaft (1), ring gear (R1) is driven by the transfer shaft (5) It is connected so that it can be delivered.

The second planetary gear PG2 has an element that is variably connected to the input shaft 1, and an element that is fixedly connected to two elements of the first planetary gear PG1, respectively.

The second planetary gear PG2 includes a single pinion planetary gear, and a sun gear S2 thereof is variably connected to the input shaft 1, and a carrier Ca2 is connected to the sun gear S1 of the first planetary gear PG1. Fixed and variably connected to the transmission housing 3, respectively, the ring gear R2 is fixedly connected to the carrier Ca1 of the first planetary gear PG1.

In addition, the third planetary gear PG3 is an element that is variably connected to the input shaft 1, an element that transmits power to the transfer shaft 5, one element of the second planetary gear PG2 and the transmission housing 3, respectively. It has elements that are fixed and variable connected.

The third planetary gear (PG3) is composed of a single pinion planetary gear, its sun gear (S3) is variably connected to the input shaft (1), the carrier (Ca3) is connected so as to transfer power to the transfer shaft (5). The ring gear R3 is fixedly and variably connected to the carrier Ca2 of the second planetary gear PG2 and the transmission housing 3, respectively.

On the other hand, the first clutch C11 is provided between them to variably connect the input shaft 1 and the sun gear S3 of the third planetary gear PG3, and the second clutch C2 is the input shaft 1 and the first clutch. It is installed between them so as to variably connect the carrier Ca1 of the planetary gear PG1, and the third clutch C3 is variably connected between the input shaft 1 and the sun gear S1 of the first planetary gear PG1. The fourth clutch C4 is installed therebetween so as to variably connect the input shaft 1 and the sun gear S2 of the second planetary gear PG2.

The first brake B1 may vary the sun gear S1, the carrier Ca2, and the ring gear R3 of each of the first, second, and third planetary gears PG1, PG2, and PG3 that are fixedly connected to the transmission housing 3. Installed between them to connect.

As described above, the gear train including the first, second, and third planetary gears PG1, PG2, and PG3 is transferred to the first, second, third, and fourth clutches C1, C2, C3, C4, and the first brake B1. Control to transfer the outputs of forward 5 speed and reverse 1 speed to the transfer shaft 5 through the ring gear R1 of the first planetary gear PG1 and the carrier Ca3 of the third planetary gear PG3. The first and second transfer drive gears 7 and 9 fixedly connected to each other are respectively engaged with the first and second transfer driven gears 11 and 13 mounted on the transfer shaft 5.

In the gear train for the automatic transmission configured as described above, the transmission control unit (TCU) is a hydraulic control system according to the driving state of the vehicle such as the vehicle speed and the throttle opening degree, and the first, second, third and fourth clutches C1, C2, By selectively operating and releasing C3, C4 and the first brake B1 as shown in Fig. 2, the fifth forward speed and the first reverse speed are realized.

That is, the first, second, third and fourth clutches C1, C2, C3, C4 and the first brake B1 are released in the D range angular speed and the R range, as shown in FIG. The three planetary gears PG1, PG2 and PG3 are indicated by the first, second, third, fourth and fifth levers L1, L2, L3, L4 and L5 as shown in FIGS. 3, 4, 5, 6 and 7. do.

These first, second, third, fourth, and fifth levers L1, L2, L3, L4, and L5 represent first, second, and third elements representing the elements of the first, second, and third planetary gears PG1, PG2, and PG3. It is represented by 3, 4, 5, 6 nodes (N1, N2, N3, N4, N5, N6).

That is, the first node N1 is the sun gear S3 of the third planetary gear PG3, and the second node N2 is the carrier Ca1 and the ring gears of the first and second planetary gears PG1 and PG2, respectively. R2), the third node (N3) is a ring gear (R1) of the first planetary gear (PG1), the fourth node (N4) is a carrier (Ca3), the fifth node (N5) of the third planetary gear (PG3) The sun gear S1, the carrier Ca2, the ring gear R3, and the sixth node N6 of each of the first, second, and third planetary gears PG1, PG2, and PG3 are sun gears of the second planetary gear PG2. S2) means respectively.

Therefore, in the following description, the operation state of each shift stage for each range will be described referring to each node in place of each element of the first, second and third planetary gears PG1, PG2 and PG3.

(D range 1 speed)

Since the first clutch C1 and the first brake B1 are operated in the D range 1 speed state, the third and fourth nodes N3 and N4 are output elements at the first lever L1 as shown in FIG. 3. The fifth node N5 is a reaction force element, and the first node N1 is an input element. In this case, it is assumed that the output of the third node N3 is 1 and the output of the fourth node N4 is smaller than the output of the third node N3. This determines the gear ratio of the first and second transfer drive gears 7 and 9 and the first and second transfer driven gears 11 and 13.

Therefore, if the position of the reaction force element, the fifth node (N5) and the third node (N3) 1 position (not included in the vertical direction or less), and the fourth node (N4) a predetermined ratio position (omitted below the vertical direction), the first speed It becomes the line l1. In this case, the size of the vertical direction in the first node N1 as the input element is the input speed ratio D1 of the D range 1 to the output 1.

That is, it can be seen that in the D range 1 speed, the output is decelerated compared to the input speed ratio D1 of the D range 1 speed. In addition, it can be seen that the fourth node N4 always maintains a lower ratio than the third node N3.

(D-range 2 speed)

When the vehicle speed and the throttle opening degree reach the second speed condition in the above D range 1 speed state, the transmission control unit (TCU) realizes the second speed control.

That is, in the D range 2 speed state, since the first clutch C1 is released and the second clutch C2 is operated while the first brake B1 is operated, as shown in FIG. In L1) only the input element is switched to the second node N2.

Therefore, when the fifth node N5, which is the reaction force element, and the third node N3, the position 1, and the predetermined ratio position of the fourth node N4 are connected, the second speed line l2 is obtained. In this case, the size of the vertical direction in the second node N2, which is an input element, is an input speed ratio D2 of the D range 2 speed with respect to the output 1.

In other words, in the D range 2 speed, the input speed ratio D2 of the D range 2 speed is smaller than the input speed ratio D1 of the D range 1 speed to the same output as the D range 1 speed. Able to know. And it can be seen that the output of D-Layer 2 speed is decelerated.

(D-range 3 speed)

When the vehicle speed and the throttle opening degree reach the 3 speed condition in the above D range 2 speed state, the transmission control unit TCU realizes the 3 speed control.

That is, in the D range 3 speed state, since the first brake B1 is released while the second clutch C2 is operated, and the third clutch C3 is operated, as shown in FIG. 4, the second lever ( In L2), the third and fourth nodes N3 and N4 are output elements, and the second and fifth nodes N2 and N5 are input elements.

In this case, it is assumed that the output of the third node N3 is one. Then, the fourth node N4 has an output in the same ratio as the output speed ratio of the fourth node N4 at 1,2 speeds.

Accordingly, when the fifth and sixth nodes N5 and N6 are connected while connecting the position 1 of the third node N3 and the position of the same size of the second node N2, the first third speed line l3 'is connected. When the position of the fifth node N5, the position of the ratio of the fourth node N4, and the predetermined position of the first node N1 are connected, a second third speed line l3 "is obtained.

That is, in the D range 3 speed, the output speed ratio D3 of the D range 3 speed is smaller than the input speed ratio D2 of the D range 2 speed for the same output as the D range 2 speed. It can be seen that it is increased. And the output of D-Ray 3 speed has the same speed ratio as the input. In addition, it can be seen that the fourth node N4 always maintains a lower ratio than the third node N3.

(D-range 4 speed)

If the vehicle speed and the throttle opening degree reach the 4 speed conditions in the above D range 3 speed state, the transmission control unit (TCU) realizes 4 speed control.

That is, in the D range 4 speed state, since the second clutch C2 is released while the third clutch C3 is operated, and the first clutch C1 is operated, as shown in FIG. 5, the third lever ( In L3), the third and fourth nodes N3 and N4 are output elements, and the first and fifth nodes N1 and N5 are input elements.

In this case, it is assumed that the output of the third node N3 is one. Then, the fourth node N4 has the same output ratio as the output speed ratio of the fourth node N4 at 1,2,3 speed.

Therefore, if the position of the above ratio of the fourth node N4 and the position of the above ratio of the first and fifth nodes N1 and N5 are connected, the first fourth speed diagram l4 'is obtained and the third node When the second and sixth nodes N2 and N6 are connected while the position of 1 of N3 and the position of the above ratio of the fifth node N5 are connected, it becomes the second 4-speed line l4 ". .

That is, in the D range 4 speed, the output speed ratio D4 in the D range 4 speed is smaller than the input speed ratio D3 in the D range 3 speed for the same output as the D range 3 speed. It can be seen that it is increased. And it can be seen that the output of D-Layer 4 speed is increased. In addition, it can be seen that the fourth node N4 always maintains a lower ratio than the third node N3.

(D-range 5 speed)

When the vehicle speed and the throttle opening degree reach the 5-speed condition in the D-range 4-speed state as described above, the transmission control unit (TCU) realizes 5-speed control.

That is, in the D range 5 speed state, since the third clutch C3 is released while the first clutch C1 is operated and the fourth clutch C4 is operated, as shown in FIG. 6, the fourth lever ( In L4), the third and fourth nodes N3 and N4 are output elements, and the first and sixth nodes N1 and N6 are input elements.

In this case, it is assumed that the output of the third node N3 is one. Then, the fourth node N4 has the same output ratio as the output speed ratio of the fourth node N4 at 1,2,3,4.

Therefore, when the position of the above ratio of the fourth node N4 and the predetermined position of the first node N1 lower than the fourth node N4 and the fifth node N5 are connected, the first fifth speed line l5 is connected. '), The position of the sixth node (N6) and the third node (N3) having the same size as the first node (N1) and the position of the fifth node (N5), the second node (N2) If the predetermined position is connected, it becomes the 2nd 5-speed line l5 ".

That is, in the D range 5 speed, the output speed ratio D5 of the D range 5 speed is smaller than the input speed ratio D4 of the D range 4 speed for the same output as the D range 4 speed. It can be seen that it is increased. And it can be seen that the output of D-speed 5 is increased. In addition, it can be seen that the fourth node N4 always maintains a lower ratio than the third node N3.

(R range 1 speed)

Since the fourth clutch C4 and the first brake B1 are operated in the R range 1 speed state, the third and fourth nodes N3 and N4 are output elements at the fifth lever L5 as shown in FIG. 7. The fifth node N5 is a reaction force element, and the sixth node N6 is an input element. In this case, it is assumed that the output of the third node N3 is 1 and the output of the fourth node N4 is smaller than the output of the third node N3. This is set by the first and second transfer drive gears 7 and 9 and the first and second transfer drive gears 11 and 13.

Therefore, when the position where the fifth node N5 and the third node N3, which are reaction force elements, is one and the ratio position of the fourth node N4, is connected, the R range 1 speed curve lR1 is obtained. In this case, the size of the vertical direction in the sixth node N6, which is an input element, is an input speed ratio r1 of the R range 1 speed with respect to the output 1. Here, the input speed ratio r1 of the R range 1 speed is lowered from the fifth lever L5 because the output 1 is assumed to be upward.

That is, it can be seen that in the R range 1 speed, the output is reverse to the input rotation direction.

As described above, the gear train for an automatic transmission according to the present invention effectively combines three planetary gears, four clutches, and one brake to selectively operate and release the clutch and the brake, thereby realizing 5 forward speeds and 1 reverse speed. ;

In addition, the number of clutches and brakes can be reduced to realize miniaturization and light weight, and the power efficiency can be improved by reducing non-operating friction elements causing power loss.

Claims (12)

A first planetary gear having two elements variably connected to the input shaft and one element for transmitting power to the transfer shaft; A second planetary gear having three elements variably connected to the input shaft, and two elements each of which is fixedly connected to two elements of the first planetary gear; Two elements variably connected to the input shaft, one element transmitting power to the transfer shaft, and one fixed and variably connected to one element of the second planetary gear and the transmission housing, respectively, of two elements connected to the input shaft. A third planetary gear having three elements; The first, second, and third planetary gears fixed and variably connected to the first and second planetary gears may be transferred to the transfer shaft by shifting the input transmitted to the input shaft to 5 forward speeds and 1 reverse speed as described above. An automatic transmission including first, second, third, and fourth clutches for variably connecting specific elements to the input shaft, and first brakes for variably connecting specific elements of the first, second and third planetary gears fixedly connected to the transmission housing; Gear train. The gear train of claim 1, wherein the first planetary gear is configured as a double pinion planetary gear. The gear train of claim 1 or 2, wherein the first planetary gear is variably connected to a sun gear and a carrier to the input shaft, and a ring gear is connected to transfer power to the transfer shaft. The gear train of claim 1, wherein the second planetary gear is configured as a single pinion planetary gear. The method of claim 1 or 4, wherein the second planetary gear is a sun gear is variably connected to the input shaft, the carrier is fixed and variably connected to the sun gear and the transmission housing of the first planetary gear, respectively, the ring gear is the first planetary Gear train for an automatic transmission, characterized in that it is fixedly connected to the carrier of the gear. The gear train of claim 1, wherein the third planetary gear is configured as a single pinion planetary gear. The method of claim 1 or 6, wherein the third planetary gear is a sun gear is variably connected to the input shaft, the carrier is connected to transfer power to the transfer shaft, a ring gear is the carrier of the second planetary gear and the transmission housing Gear train for automatic transmission, characterized in that it is fixed and variablely connected to each other. The gear train of claim 1, wherein the first clutch is disposed between the input shaft and the sun gear of the third planetary gear so as to variably connect the input shaft and the sun gear of the third planetary gear. The gear train of claim 1, wherein the second clutch is disposed between the input shaft and the carrier of the first planetary gear so as to variably connect the input shaft and the carrier of the first planetary gear. The gear train of claim 1, wherein the third clutch is disposed between the input shaft and the sun gear of the first planetary gear so as to variably connect the input shaft and the sun gear of the first planetary gear. The gear train of claim 1, wherein the fourth clutch is disposed between the input shaft and the sun gear of the second planetary gear so as to variably connect the input shaft and the sun gear of the second planetary gear. The sunshade of claim 1, wherein the first brake is configured to variably connect the sun gear, the carrier, and the ring gear of each of the first, second and third planetary gears fixedly connected to the transmission housing. Gear train for an automatic transmission, characterized in that it is installed between the carrier, the ring gear and the transmission housing.

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