KR100309014B1 - Gear train for automatic transmission - Google Patents

Abstract

PURPOSE: A gear train for an automatic transmission is provided to realize forward five speeds and backward one speed by using three planetary gears and four frictional elements, to reduce weight and size, and to improve power efficiency. CONSTITUTION: A gear train for an automatic transmission comprises first, second and third planetary gears(PG1,PG2,PG3), first, second and third clutches(C1,C2,C3), and a first brake(B1) variably connecting a specific element of the first planetary gear to a transmission housing(3). A second brake(B2) variably connects one element of the third planetary gear to the transmission housing. A ring gear(R1) of the first planetary gear transmits power to a transfer shaft(5). A carrier(Ca2) of the second planetary gear transmits power to the transfer shaft. A ring gear(R3) of the third planetary gear transmits power to the transfer shaft. First and second transfer drive gears(7,9) are engaged at a specific gear ratio to transmit power to first and second transfer driven gears(11,13).

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 disadvantages, and the object of the present invention is to achieve miniaturization and light weight while achieving forward 5 speed and reverse 1 speed with three planetary gears and four friction elements, 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.

Fig. 8 is a speed diagram showing an R range 1 * speed shift ratio 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, B2: first and second brake, C1, C2, C3 1, 2, 3 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;

In order to control these planetary gears to achieve 5 forward speeds and 1 reverse speed, four friction elements selectively variablely connect the input shaft, each element of the planetary gear, and the transmission housing.

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, an element variably connected to the transmission housing, and an element connected to transfer power to the transfer shaft;

A second planetary gear having an element fixedly connected to one element of the first planetary gear and an element fixedly connected to the element to transmit power to the transfer shaft together with the other element of the first planetary gear;

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

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. First, second, and third clutches which variably connect to the input shaft, and first brakes which variably connect specific elements of the first planetary gear to the transmission housing.

In the gear train for an automatic transmission of the present invention configured as described above, the hydraulic control system moves forward by selectively operating and releasing the first, second, and third clutches and the first brake to control the first, second and third planetary gears. Realizes 1st speed and 2nd speed.

In other words, the first and second clutches in D range 1, the second and first brakes in D range 2, the first and second clutches in D range 3, the second and third clutches in D range 4, and the 5th range in D range In the first and third clutches and R range 1 speed, the third 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 four or 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) And a first brake B1 for variably connecting the first, second and third clutches C1, C2 and C3 and the specific elements of the first planetary gear PG1 to the transmission housing 3.

The gear train also has a second brake B2 which variably connects one element of the third planetary gear PG3 to the transmission housing 3 so that it can be selectively used at a particular gear stage.

The first planetary gear PG1 has an element variably connected to the input shaft 1, an element variably connected to the transmission housing 3, and an element connected to transfer power to the transfer shaft 5.

The first planetary gear (PG1) is composed of a single pinion planetary gear, its sun gear (S1) is variably connected to the input shaft (1), the carrier Ca1 is variably connected to the transmission housing (3), ring gear R1 is connected to transfer power to the transfer shaft 5.

The second planetary gear PG2 is fixedly connected to one element of the first planetary gear PG1 and the other element of the first planetary gear PG1 to transfer power to the transfer shaft 5 together with the other element. Has an element that is fixedly connected to it.

The second planetary gear PG2 includes a single pinion planetary gear, and its sun gear S2 is fixedly connected to the sun gear S1 of the first planetary gear PG1, and the carrier Ca2 is transferred to the transfer shaft 5. It is fixedly connected to the ring gear (R1) of the first planetary gear (PG1) to transmit power to the furnace.

In addition, the third planetary gear PG3 is an element that is variably connected to the input shaft 1, an element that is variably connected to the input shaft 1 and the transmission housing 3 and fixedly connected to one element of the second planetary gear PG2. It has an element for transmitting power to the transfer shaft (5).

The third planetary gear PG3 includes a single pinion planetary gear, and its sun gear S3 is variably connected to the input shaft 1, and the carrier Ca3 is variably connected to the input shaft 1. It is fixedly connected to the ring gear R2 of the gear PG2, and the ring gear R3 is connected to transmit power to the transfer shaft 5.

The carrier Ca3 of the third planetary gear PG3 is variably connected to the transmission housing 3.

On the other hand, the first clutch C1 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 third. It is installed between them so as to variably connect to the carrier Ca3 of the planetary gear PG3, and the third clutch C3 is therebetween so as to variably connect the input shaft 1 and the sun gear S1 of the first planetary gear PG1. Is installed on.

The first brake B1 is installed therebetween to variably connect the carrier Ca1 of the first planetary gear PG1 to the transmission housing 3. In addition, the second brake B2, which operates only at a specific shift stage, converts the carrier Ca3 of the third planetary gear PG3 fixedly connected to the ring gear R2 of the second planetary gear PG2 to the transmission housing 3. It is installed between them to connect.

As described above, the gear train including the first, second, and third planetary gears PG1, PG2, and PG3 includes the first, second, and third clutches C1, C2, and C3 and the first brake B1 or the second brake ( B2), the ring gears R1 and R3 of each of the first and third planetary gears PG1 and PG3 transmit first and second transfer drives so as to transmit the outputs of the fifth forward speed and the first reverse speed to the transfer shaft 5. The first and second transfer drive gears 7 and 9 are fixedly connected to the gears 7 and 9, respectively, and may transfer power to the first and second transfer driven gears 11 and 13 installed in the transfer shaft 5. So that they are engaged at a constant gear ratio.

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, and the first, second, and third clutches (C1, C2, C3). And first and second brakes B1 and B2 are selectively operated and released as shown in FIG. 2, thereby realizing 5 forward speeds and 1 reverse speed.

That is, the first, second and third clutches C1, C2 and C3 and the first and second brakes B1 and B2 are released in the D range angular speed and the R range 1 speed as shown in FIG. 2,3 planetary gears (PG1, PG2, PG3) are the first, second, third, fourth, fifth, sixth lever (L1, L2, L3, L4, L5, L6).

These first, second, third, fourth, fifth, and sixth levers L1, L2, L3, L4, L5, and L6 represent the elements of the first, second, and third planetary gears PG1, PG2, and PG3. 1,2,3,4,5,6 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 ring gear R2 and the carrier of each of the second and third planetary gears PG2 and PG3. Ca3), the third node N3 is the ring gear R3 of the third planetary gear PG3, and the fourth node N4 is the ring gear R1 of the first and second planetary gears PG1, PG2 and the carrier. (Ca2), the fifth node N5 is the carrier Ca1 of the first planetary gear PG1, and the sixth node N6 is the sun gear S1, S2 of the first and second planetary gears PG1, PG2. Each means.

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 fourth node N4 is 1 and the output of the third node N3 has a predetermined ratio greater than that of the fourth node N4. 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, when the first node N1 and the first node N1 and the predetermined position of the fifth node N5 and the fourth node N4 are connected to each other, a first speed line l1 is obtained. 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, since the input speed ratio D1 of the D range 1 speed is greater than the output 1, it can be seen that the output is decelerated at the D range 1 speed.

(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, the first lever L1 as shown in FIG. 3. ) And only the input element is switched from the first node (N1) to the second node (N2).

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

That is, 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 with respect to the same output as the D range 1 speed. It can be seen that it is increased. In addition, since the input speed ratio D2 of the D range 2 speed is greater than the output 1, the output is decelerated even in the D range 2 speed.

(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 and the first clutch C1 is operated while the second clutch C2 is operating, the second lever L2 is illustrated in FIG. 4. ), The first, second and third planetary gears PG1, PG2 and PG3 form different first and second three-speed diagrams l3 'and l3 ", and the input elements are first and second nodes N1 and N2. ).

Therefore, when the position of the second node N2 and the position of the first and third nodes N1 and N3 of the same size are connected on the second third speed line ℓ3 ″, the first and second nodes N1 and N2 as input elements are connected. ), The vertical direction is the input speed ratio D3 of D range 3 speed to output 1.

That is, in the D range 3 speed, the input speed ratio D3 of the D range 3 speed becomes 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.

(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 first clutch C1 is released and the third clutch C3 is operated while the second clutch C2 is operated, the third lever L3 as shown in FIG. 5. ), The first, second and third planetary gears PG1, PG2 and PG3 form different first and second four speed diagrams l4 'and l4 ", and the input elements are second and six nodes N2 and N6. ).

Therefore, when the position of the second node N2 and the fourth and sixth nodes N4 and N6 having the same size are connected on the first fourth speed line ℓ4 ', the second node N2 as an input element is perpendicular to the vertical direction. The position of the sixth node N6, which is another input element of the same size as the second node N2, is the input speed ratio D4 of the D range 4 speed to the output 1.

That is, in the D range 4 speed, the input speed ratio D4 of the D range 4 speed becomes smaller than the input speed ratio D3 of the D range 3 speed for the same output as the D range 3 speed, so the output of the D range 4 speed is lower than that of the D range 3 speed. It can be seen that it is increased. And it can be seen that the input speed ratio D4 of the D range 4 speed is equal to the output 1.

(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 second clutch C2 is released and the first clutch C1 is operated while the third clutch C3 operates, the fourth lever L4 as shown in FIG. 6. ), The first, second and third planetary gears PG1, PG2 and PG3 form different first and second five speed diagrams l5 'and l5 ", and the input elements are the first and sixth nodes N1 and N6. ).

Therefore, the position of the sixth node N6 having a size smaller than 1, the position of 1 of the fourth node N4, and the predetermined position of the second node N2 are connected to each other, and the second position on the second 5-speed line? 5 " When the position of the node N2 and the position of the small node of the third node N3 and the position of the first node N1 having the same size as the sixth node N6 are connected, the first and sixth nodes that are the same input element ( In N1, N6), the vertical direction is the input speed ratio D5 of D-speed 5 to output 1.

That is, in the D range 5 speed, the input speed ratio D5 of the D range 5 speed becomes 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. In addition, since the input speed ratio D5 of the D range 5 speed is smaller than the output 1, the output speed is increased at the D range 5 speed.

(R range 1 speed)

Since the third clutch C3 and the first brake B1 are operated in the R range 1 speed state, the first, second, and third planetary gears PG1, PG2, and PG3 are operated in the fifth lever L5 as shown in FIG. 7. ) Forms an R-range 1 speed diagram lR1, an output element is a third and fourth nodes N3 and N4, a reaction force element is a fifth node N5, and an input element is a sixth node N6.

Therefore, when the positions of the third, fourth nodes (N3, N4), the fifth node (N5), and the sixth node (N6) are smaller than zero on the R range 1 speed line lR1, the sixth node, which is an input element, is connected. In (N6), the size in the vertical direction is the input speed ratio r1 of the R range 1 speed to the output 1. The reason why the input speed ratio r1 of the R range 1 speed falls below 0 in the fifth lever L5 is because the output 1 is assumed to be 0 or more.

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

(R range 1 * speed)

Since the first clutch C1 and the second brake B2 are operated in the R range 1 * speed state, the first, second and third planetary gears PG1, PG2, and the sixth lever L6 as shown in FIG. 8 are operated. PG3) forms the first and second R range 1 * speed diagrams (lR1 * ', lR1 * "), the output elements are third and fourth nodes (N3 and N4), and the reaction force elements are second nodes (N2), The input element is the first node N1.

Therefore, when the predetermined position of the second node N2 and the third node N3 and the predetermined position of the first node N1 are connected on the first R range 1 * speed line lR1 * ', the first element, which is an input element, is connected. The magnitude in the vertical direction at node N1 is the input speed ratio r1 * in R range 1 * to output 1. The reason why the input speed ratio r1 * in the R range 1 * falls below zero in the sixth lever L6 is because output 1 is assumed to be zero or more.

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

As described above, the gear train for the automatic transmission according to the present invention effectively combines three planetary gears, three 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 (13)

A first planetary gear having a first operating element variably connected to the input shaft, a second operating element variably connected to the transmission housing, and a third operating element connected to transfer power to the transfer shaft; A fourth actuating element fixedly connected to the first actuating element of the first planetary gear, a fifth actuating element fixedly connected to transfer power to the third actuating element of the first planetary gear, and a sixth actuating element; A second planetary gear having an operating element; A seventh actuating element variably connected to the input shaft, an eighth actuating element variably connected to the input shaft and the transmission housing and fixedly connected to the sixth actuating element of the second planetary gear, and a ninth actuation for transmitting power to a transfer shaft A third planetary gear having an element; The first, seventh, and eighth operating elements are configured to transmit the first, second, and third planetary gears fixed and variably connected to the input shaft to the forward shaft and the forward five speeds to the first shaft. And first and second brakes for variably connecting the first, second, third clutches to the input shaft, and the second and seventh operating elements to the transmission housing. The gear train of claim 1, wherein the first planetary gear is configured as a single pinion planetary gear. The gear train of claim 1 or 2, wherein the first planetary gear has a sun gear variablely connected to the input shaft, a carrier variablely connected to the transmission housing, and a ring gear 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 automatically characterized in that its sun gear is fixedly connected to the sun gear of the first planetary gear and the carrier is fixedly connected to the ring gear of the first planetary gear to transfer power to the transfer shaft. Gear train for transmission. The gear train of claim 1, wherein the third planetary gear is configured as a single pinion planetary gear. The third planetary gear according to claim 1, wherein the third planetary gear is variably connected to the input shaft, the carrier is variably connected to the input shaft, and is fixedly connected to the ring gear of the second planetary gear, and the ring gear transfers power to the transfer shaft. Gear train for an automatic transmission, characterized in that it is connected. 8. The gear train of claim 7, wherein the carrier of the third planetary gear is variably connected to the transmission housing. The gear train of claim 1, wherein the first clutch is disposed therebetween 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 therebetween so as to variably connect the input shaft and the carrier of the third planetary gear. The gear train of claim 1, wherein the third clutch is disposed therebetween 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 first brake is disposed therebetween so as to variably connect the carrier of the first planetary gear to the transmission housing. The gear train of claim 1, wherein the second brake is disposed therebetween so as to variably connect the carrier of the third planetary gear to the transmission housing.

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