KR100279402B1 - Stepless Transmission for Vehicles - Google Patents

Abstract

It is an object of the present invention to provide a continuously variable transmission device for providing a variety of driving modes in the stepless speed change by the low speed and high speed stage setting, and to improve the initial starting acceleration performance by the low speed step; An oscillation means for transmitting the rotational power output from the engine to the first shaft; A shifting means composed of a composite planetary gear set for shifting to two forward and one reverse speeds with respect to the rotational power output from the oscillation means; Stepless speed shifting means disposed between the output end of the speed shifting means and a second shaft disposed at a predetermined interval below the speed shifting means for continuously transmitting a rotational power transmitted from the speed shifting means to the second shaft; A center differential means for vertically decelerating the rotational power transmitted from the continuously variable transmission means and distributing it to the front and rear wheels; Front wheel driving means for transmitting the power outputted from the differential means to the front wheels and driving them; And a rear wheel drive means for transmitting the power output from the differential means to the rear wheels to drive the rear wheels.

Description

Stepless Transmission for Vehicles

1 is a block diagram of a first embodiment according to the present invention.

Figure 2 is a block diagram showing an embodiment of a continuously variable transmission means applied to the present invention.

3 is an operating table of a friction element applied to the present invention.

4 is a diagram for explaining the shift process of the present invention by lever analysis method.

5 is a configuration diagram of a second embodiment according to the present invention.

The present invention relates to a continuously variable transmission for a vehicle, and more particularly, to provide various driving modes with continuously variable speed by low speed and high speed stage setting, and to improve initial starting acceleration performance by a low speed stage, and a four-wheel drive vehicle. It relates to a continuously variable transmission for a vehicle that can be applied to.

The transmission of the vehicle has a function of transmitting the driving force of the engine to the driving wheels. The transmission includes a manual transmission that directly selects a shift stage at the driver's will, and an automatic transmission in which a shift is automatically made according to driving conditions of the vehicle. The apparatus is roughly classified into a continuously variable transmission in which stepless continuous shifting is performed without a specific shift range between each gear stage.

In the above-described transmission apparatus, the present invention relates to a continuously variable transmission having great advantages in terms of fuel economy, power transmission performance, and weight by supplementing the disadvantages of the automatic transmission using hydraulic pressure.

In forming such a continuously variable transmission, conventionally, a continuously variable transmission means using a pulley having a variable diameter and a belt is used, which allows the continuous transmission using one or two continuously variable transmission means.

However, in the continuously variable transmission as described above, since there is a limit in realizing the speed ratio required in the initial stage of oscillation, the initial oscillation performance and acceleration performance are not good, and thus it is not practically used.

Therefore, the present invention has been invented to solve the above problems, an object of the present invention is to provide a variety of driving modes with a continuously variable speed by the low speed and high speed stage setting, it is possible to improve the initial oscillation acceleration performance by the low speed stage The present invention also provides a continuously variable transmission for a vehicle that can be applied to a four-wheel drive vehicle.

In order to realize this, the present invention includes an oscillating means for transmitting the rotational power output from the engine to the first shaft; A shifting means composed of a composite planetary gear set for shifting to two forward and one reverse speeds with respect to the rotational power output from the oscillation means; Stepless speed shifting means disposed between the output end of the speed shifting means and a second shaft disposed at a predetermined interval below the speed shifting means for continuously transmitting a rotational power transmitted from the speed shifting means to the second shaft; A center differential means for vertically decelerating the rotational power transmitted from the continuously variable transmission means and distributing it to the front and rear wheels; Front wheel driving means for transmitting the power outputted from the differential means to the front wheels and driving them; Rear wheel driving means for transmitting the power output from the differential means to the rear wheels and driving them; It is characterized by providing a continuously variable transmission for a vehicle comprising a.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention that can specifically realize the above object will be described in detail.

1 is a configuration diagram of the first embodiment according to the present invention, which shows an example in which the torque converter 4 is applied as the oscillation means 2.

The torque converter 4 includes a pump impeller 8 which rotates in direct connection with the crankshaft of the engine 6; A turbine runner 10 which is disposed to face the pump impeller 8 and rotates together by oil ejected; And a stator 12 disposed between the pump impeller 8 and the turbine runner 10 to change the flow of oil to increase the rotational force of the pump impeller 8.

Accordingly, when the engine rotates, the oil filled in the torque converter 4 is ejected from the pump impeller 8 and supplied to the turbine runner 10 to drive the turbine runner 10 and then flow into the stator 12. .

In addition, the oil introduced into the stator 12 changes the direction and repeats the flow of the oil into the pump impeller 8, in which the turbine runner shared by the stator 12 is rotated by the rotation of the stator 12. There is a difference between the rotational force of 10) and the rotational force of the pump, which is the torque conversion.

In addition, the rotational power output through the oscillation means 2 is controlled to move forward and backward of the vehicle according to the driver's will by the transmission means 16 disposed on the first shaft 14.

The shift means 16 is composed of a compound planetary gear set to control the shift stage of the two forward, one reverse.

The composite planetary gear set includes a first single pinion planetary gear set 18 and a second single pinion planetary gear set 20.

That is, the first shaft 16 formed integrally with the sun gear 22 of the first single pinion planetary gear set 18 has a rear portion 24 of the sun gear 24 of the second single pinion planetary gear set 20. It is connected to the transmission housing 28 via the first friction element 26 in the middle portion thereof, so that the sun gear 24 can selectively act as a reaction force element.

A second friction element 30 is disposed between the first friction element 26 and the sun gear 22 of the first single pinion planetary gear set 18 so that the second single pinion planetary gear set 20 is disposed. The sun gear 24 can be selectively operated as an input element.

In addition, the carrier 32 of the first single pinion planetary gear set 18 is connected to the ring gear 34 of the second single pinion planetary gear set 20, and a connection member 36 connecting the same. Is connected to the transmission housing 28 via a third friction element 38 so that they can selectively act as a reaction element, the ring gear 40 of the first single pinion planetary gear set 18 is a second It connected with the carrier 42 of the single pinion planetary gear set 20, and the carrier 42 of the single pinion planetary gear set 20 is the output end.

By the above configuration, the rotational power of the engine 6 is input to the continuously variable transmission means 16 through the torque converter 4 to maintain the idle state in the neutral state.

Looking at the forward and backward shifting process in this state looking at 3 and 4 as follows.

First, in FIG. 4, the first node N1 is the sun gear 22 and the second gear of the single pinion planetary gear set 18 as a diagram of a lever analysis method for visually analyzing the operation process of the composite planetary gear set. The node N2 is the carrier 32 of the first pinion planetary gear set 18, the ring gear 34 of the second single pinion planetary gearset 20, and the third node N3 is the first pinion. The ring gear 40 of the planetary gear set 18 and the carrier 42 and the fourth node N4 of the second single pinion planetary gear set 20 are the sun gears of the second single pinion planetary gear set 20. 24) is displayed.

The configuration of such a node is known as being set by the connection relationship between the two single pinion planetary gear sets 18, 20.

If the driver selects the select lever in the "D" range for the forward driving under the preconditions described above, the transmission control unit operates the first friction element 26.

Then, the rotational power of the engine is input through the sun gear 22 of the first single pinion planetary gear set 18, and the second single pinion planetary gear set 20 is operated by the operation of the first friction element 26. ), The first gear is made while the sun gear 24 is acting.

That is, as shown in FIG. 4, the sun gear 24, which is the fourth node N4, acts as a reaction element in the state where the input is made to the speed input line of the first node N1. The line connecting L1 and the third node N3 acting as the output element most closely becomes the low speed line D1.

The output is made relatively smaller than the input, and the rotational power thus shifted is continuously changed by the continuously variable means described below.

When the throttle opening angle and the vehicle speed increase during the forward low speed driving, the transmission control unit releases the operation of the first friction element 26 and controls the operation of the second friction element 30.

Then, the input is simultaneously performed through the sun gear 22 of the first single pinion planetary gear set 18 and the sun gear 24 of the second single pinion planetary gear set 20.

When the input is made through the two sun gears 22 as described above, the operation of the planetary gear set results in a direct connection. As shown in FIG. 4, the speed input line of the first node N1 and the fourth node ( The line L2 connecting the input speed lines of N4 to each other and the third node N3 serving as the output element closest to each other become a high speed line D2.

The input and the output are made the same, and the rotational power thus shifted is continuously changed by the continuously variable means described below.

When the select lever is selected as the "R" range during the reverse driving, the third friction element 38 is operated by the transmission control unit.

Then, the rotational power of the engine is input through the sun gear 22 of the first single pinion planetary gear set 18, and the first and second single pinion planetary gear sets are operated by the operation of the third friction element 38. A reverse shift is made while the carrier 32 and the ring gear 34 of the 18 and 20 act as reaction elements.

That is, as shown in FIG. 4, the second node N2 acts as a reaction force element while the input is made to the speed input line of the first node N1, and the straight line L3 connecting them to each other, The line that most closely connects the third node N3, which acts as an output element, becomes the speed line R1 of reverse.

Therefore, the output is made in the opposite direction with respect to the input so that the reverse driving is possible.

In the shifting means 16 of the present invention as described above, the output of two forward and one reverse.

As described above, the rotational power that is shifted by the shifting means 16 is continuously shifted by the continuously variable shifting means 44.

The continuously variable transmission means 44 is formed on a carrier 42 forming an output end of the composite planetary gear set and a second shaft 46 arranged in parallel with a predetermined distance below the first shaft 14. It comprises a drive and driven pulleys (48) (50) 50 arranged and variable in diameter by hydraulic pressure, and a belt (52) for interconnecting the pulleys.

As described above, the driving and driven pulleys 48 and 50 allow the endless speed change to be made by the change of the diameter, and FIG. 2 shows a configuration of one embodiment for making it possible.

The drive pulley 48 is composed of a fixed side sheave 54 and a variable side sheave 56, the fixed side sheave 54 is formed integrally with the carrier 42, the variable side sheave ( 56 is coupled in such a state that it can move left and right on the carrier 42.

A casing member 58 is provided on the side of the variable side shaft 56 to form a hydraulic chamber 60 therebetween. The hydraulic chamber 60 is connected to the engine via a flow path 62 formed in the carrier 42. The pressure fluid generated by the driving force of the gas can be supplied.

And the driven pulley 40 is made of a fixed side sheave 64 and a variable side sheave 66 as described above, the fixed side sheave 64 is formed integrally with the second shaft 46, The variable side sheave 66 is coupled to move left and right on the second shaft 46.

In addition, the variable side sheave 66 is provided with a casing member 68 to form a hydraulic chamber 70, and the hydraulic chamber 70 through the flow path 72 formed on the second shaft 46. The pressure fluid generated by the driving force of the engine can be supplied.

Therefore, when the rotational power output from the transmission means 16 is transmitted to the continuously variable transmission means 44, the second shaft 46 is driven while the stepless speed change is performed, in which the drive pulley 38 and the driven pulley 40 are used. The shift is made according to the change of outer diameter of.

The conditions for changing the rotational speed are as follows: first, when the outer diameters of the driving pulley 38 and the driven pulley 40 are the same, and when the outer diameter of the second driving pulley 38 is larger than the diameter of the driven pulley 40; The diameter of the drive pulley 38 may be considered to be smaller than the diameter of the driven pulley 40.

In the first condition, when the outer diameters of the driving and driven pulleys 38 and 40 are the same, the transmission ratio is 1: 1.

And secondly, when the outer diameter of the drive pulley 38 is larger than the diameter of the driven pulley 40, the speed of the driven pulley 40 is increased because the rotation speed of the driven pulley 40 becomes larger, the third drive pulley When the outer diameter of 38 is smaller than the diameter of the driven pulley 40, the rotation speed of the drive pulley 38 becomes smaller than the rotation speed of the driven pulley 40, thereby decelerating.

In this way, the driving range is gradually shifted from the start point to the high speed drive without division of the gear stage.

The rotational power in which the continuously variable shift is made as described above is input to the center differential means 74.

The center differential means 74 is composed of a double pinion planetary gear set, which has its ring gear 76 engaged with the output gear 78 disposed on the second shaft 46 to serve as an input element. do.

The sun gear 80 and the planet carrier 82 are connected to the front wheel driving means 84 and the rear wheel driving means 86 on opposite sides, respectively.

Accordingly, the sun gear 80 and the planet carrier 82 receive rotational power input to the ring gear 76 while complementary to each other with large and small reaction force elements depending on the load applied thereto.

The front wheel drive means 84 is a front wheel drive gear 88 formed to one side of the sun gear 80, the differential gear 90 is engaged with the drive gear 88 thereof to perform a deceleration action, and the It comprises a differential mechanism 96 for distributing the rotational power input to the differential gear (90) while differentially acting according to the load applied to both front wheel drive shaft (92) (94).

In addition, the rear wheel drive means 86 is coupled to the rear wheel drive gear 98 mounted to the front end of the planet carrier 82, and the driven gear 100 of the front end to the front wheel drive gear 98 is engaged with the power to the rear wheel side. It consists of a drive shaft 102 for transmitting.

Of course, the rear wheel drive and driven gear 98, 100 is generally used bevel gear for transmitting power to the member orthogonal in the axial direction, is not limited to this, it is possible to transmit power in the direction orthogonal If it is gear, we are satisfied.

As described above, according to the present invention, the speed change is performed from the low speed to the high speed again in the continuously variable means 44 in the state where the first speed of the second speed forward and the first speed is made in the speed change means 16. Will be provided.

In addition, since the reduction ratio can be largely realized at the low speed stage, the initial oscillation and acceleration performance can be greatly improved, and the driving force can be greatly improved by enabling the four-wheel drive.

5 shows a second embodiment according to the present invention, in which the oscillation means 2 is formed by the torsional damper 110, and the transmission means 16 is formed on the second shaft in the first embodiment. Since the effect is the same as that of the first embodiment, detailed description is omitted.

As described above, according to the present invention, the stepless speed change is performed again while the low speed and the high speed stage are set, thereby providing various driving modes and improving the initial oscillation acceleration performance by the low speed stage.

Claims (9)

An oscillation means for transmitting the rotational power output from the engine to the first shaft; The rear portion of the first shaft, which is integrally formed with the sun gear of the first single pinion planetary gear set, is connected to the sun gear of the second single pinion planetary gear set, so that the sun gear can selectively act as a reaction force element and an input element. The first and second friction elements, and the carrier of the first single-pinion planetary gearset is connected to the ring gear of the second single-pinion planetary gearset, so as to be controlled by the third friction element. The ring gear of the single-pinion planetary gearset is connected to the carrier of the second single-pinion planetary gearset, and the rotational force output from the oscillating means is composed of a composite planetary gearset whose carrier is formed so that the rear end thereof is an output end. Shifting means for shifting with respect to two forward and one reverse gears; A drive shaft, a drive and driven pulley disposed on parallel driven shafts arranged parallel to each other at predetermined intervals, and a belt connecting the pulleys to each other, the output end of the shifting means And a continuously variable transmission means disposed between the second shaft disposed at a predetermined interval below and continuously transmitting the rotational power transmitted from the transmission means to the second shaft. It consists of a double pinion planetary gear set, and the ring gear is engaged with the output gear in which the second shaft is arranged on the outer ring so as to act as an input element, and the sun gear and the planet carrier are connected to the front wheel drive means and the rear wheel drive means on opposite sides, respectively. Center differential means for longitudinally decelerating the rotational power transmitted from the continuously variable transmission means to distribute to the front and rear wheels; Front wheel driving means for transmitting the power outputted from the differential means to the front wheels and driving them; Rear wheel driving means for transmitting the power output from the differential means to the rear wheels and driving them; A continuously variable transmission for a vehicle comprising a. The continuously variable transmission for a vehicle according to claim 1, wherein the oscillating means is formed of any one of a torque converter and a torsional damper. 2. The continuously variable transmission for a vehicle according to claim 1, wherein the first and third friction elements of the transmission means use a band brake as the brake means, and the second friction element uses a multi-plate clutch as the clutch means. The continuously variable transmission for a vehicle according to claim 1, wherein the first friction element of the transmission means is disposed between the transmission housing so that the sun gear of the second single pinion planetary gear set can act as an optional reaction force element. The method of claim 1, wherein the second friction element of the shifting means is disposed between the first single pinion planetary gear set so that the sun gear of the second single pinion planetary gear set can act as an optional input element. Continuously variable transmission for vehicles. The third friction element of claim 1, wherein the third friction element of the shifting means interconnects the carrier of the first, single-pinion planetary gearset and the ring gear of the second single-pinion planetary gearset to act as a selective reaction element. Stepless transmission for a vehicle, characterized in that disposed between the connection member and the transmission housing. 2. The front wheel drive means according to claim 1, wherein the front wheel drive means comprises: a front wheel drive gear formed on one side of the sun gear, a differential gear engaged with the drive gear to perform a deceleration action, and rotational power input to the differential gear; A continuously variable transmission for a vehicle comprising a differential mechanism for distributing while differentially acting on a load applied to a drive shaft. 2. The vehicle according to claim 1, wherein the rear wheel drive means includes a rear wheel drive gear mounted at the front end of the planet carrier and a drive shaft which is coupled to the front wheel drive gear at the front end to transfer power to the rear wheel side. Continuously variable transmission. The continuously variable transmission for a vehicle according to claim 1, wherein the transmission means is disposed on the second axis.