KR19980022105A - Stepless Transmission for Vehicles - Google Patents

Abstract

In order to sufficiently reduce the rotational force of the engine transmitted to the drive pulley to improve the transmission efficiency to the driven pulley, a torque converter receives torque from the engine and converts torque, and is connected to an input shaft directly connected to the turbine side of the torque converter. It consists of a compound planetary gear unit in which a double pinion planetary gear unit and a single pinion planetary gear unit are arranged in parallel. It controls the forward and backward movement by determining the forward and backward direction of the vehicle and controls the forward and backward rotation. Deceleration means for decelerating and endless deceleration means for receiving the rotational power output from the continuously variable transmission means by belt transmission and performing endless shifting according to the rotational speed input from both sides, and outputting the rotational power input from the continuously variable transmission means. Stepless vehicle, including gears It provides in the device.

Description

Stepless Transmission for Vehicles

1 is a block diagram of a continuously variable transmission showing an embodiment according to the present invention

Figure 2 is a block diagram of the pulley diameter displacement generating means applied to the present invention

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

4 is a graph for explaining the speed ratio of the power train of FIG. 1 by lever analysis;

* Explanation of symbols for the main parts of the drawings

4: torque converter 8: turbine

14 deceleration means 16 sun gear

17: Double Pinion Carrier 18: Double Pinion Carrier

19: long pinion 20: stepless transmission means

21: ring gear 22: drive pulley

24,36: power transmission member 26: sun gear

28: transmission case 32: belt

34: driven pulley 62: longitudinal deceleration gear device

C1: Friction element Bl: Brake means

The present invention relates to a continuously variable transmission for a vehicle, and more particularly, to a continuously variable transmission for a vehicle for improving the power transmission efficiency of the pulley mechanism of the continuously variable transmission belt so that easy start is made at the start of the ramp.

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

In the above-described transmission device, 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, and the continuously variable transmission thereof has an input shaft. The method using the diameter displacement of the pulley mounted on the output shaft is mainly used.

Such a continuously variable transmission includes a forward converter and a reverse control means disposed between the torque converter and the continuously variable transmission means or between the continuously variable transmission means and the differential device to control forward and backward movements.

As the forward and reverse control means, a simple planetary gear set is used.

The forward and backward control means used as the simple planetary gear set has a structure in which the drive shaft is directly connected to the driving pulley at the time of forward driving to transmit power 1: 1.

In the reverse drive, the power transmission ratio is 1: 1.

The continuously variable transmission device of the conventional simple planetary gear set described above has a disadvantage in that the power transmission efficiency to the driven pulley is reduced because the input rotation speed transmitted to the driving belt pulley is excessively high.

Therefore, when the vehicle is to start from the ramp, the torque transmitted to the driving wheel is reduced, there is a problem that can not be made smooth start.

The present invention has been made to solve the problems of the prior art as described above, the object of the present invention is to continuously decelerate the rotational force of the engine delivered to the drive pulley to sufficiently improve the transfer efficiency to the driven pulley To provide a transmission.

In order to realize the object of the present invention, a torque converter for converting torque by receiving power from an engine and an input shaft connected directly to the turbine side of the torque converter, and a double-pinion planetary gear device and a single pinion planetary gear device are paralleled. It consists of a compound planetary gear device which is arranged in the direction of the vehicle to determine the forward and backward direction by outputting the rotational power to control the forward and backward, the driving force pulley decelerating means and the rotational power output from the deceleration means A stepless speed changer for receiving a transmission by belt transmission and performing stepless speed change according to the number of revolutions inputted from both sides, and a vertical speed reduction gear device for longitudinally reducing and outputting the rotational power input from the stepless speed changer. to provide.

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

1 is a configuration diagram of a continuously variable transmission according to an exemplary embodiment of the present invention, in which a torque converter 4 that receives power from an engine 2 is a pump impeller that is directly connected to a crankshaft of an engine 2 and rotates. 6) and the turbine runner 8 which rotates together with the pump impeller 6 and the pump impeller 6 and the turbine runner 8 which are rotated together by the oil ejected in the opposite posture, and flows the oil. It comprises a stator 10 to change the increase the rotational force of the pump impeller (6).

Accordingly, when the engine rotates, the oil filled in the torque converter 4 is supplied to the turbine runner 8 ejected from the pump impeller 6 to drive the turbine runner 8 and then flows into the stator 10. .

In addition, the oil introduced into the stator 10 changes the direction and repeats the flow of the oil into the pump impeller 6, wherein the turbine runner shared by the stator 10 is rotated by the rotation of the stator 10. There is a difference between the rotational force of 8) and the rotational force of the pump, which is the torque conversion.

In addition, the deceleration means 14 disposed on the input shaft 12 directly connected to the turbine runner 8 has a double-pinion planetary gear set and a single pinion planetary gear set in combination with a combination of planetary type planetary gears. The device is being applied.

The composite planetary gear device is engaged with the sun gear 16 and the short pinion gear 17 from the inside to the outside, and the long pinion gear 19 is engaged with the outer circumference of the short pinion gear 17 to the inner ring of the ring gear 21. The long pinion gear 19 is made of a structure that is engaged, another sun gear 26 is made of a structure that is engaged with the long pinion gear 19 in a shared state.

The sun gear 16 on the double pinion side of the composite planetary gear device is directly connected to the input shaft 12, and the power transmission member 24 through which the double pinion carrier 18 is input to the drive pulley 22 of the continuously variable transmission means 20. ) Is always connected to the output element.

On the other hand, a friction element C1 is interposed between the sun gear 26 and the transmission case 28 on the single pinion side, so that the sun gear 26 can be selectively locked.

The friction element C1 consists of a conventional multi-plate clutch as clutch means.

A brake means B1 is interposed between the outer side of the ring gear 21 and the transmission case 28 so that the ring gear 21 can selectively act as a reaction force element.

The brake means Bl is made of a band brake.

In addition, the continuously variable transmission means 20 includes a driving pulley 22 mounted on the power transmission member 24 and an outer diameter of the driving pulley 22 and a driven pulley 34 driven by the driving pulley 22 and the belt 32. Is done.

The driven pulley 34 has a structure in which the outer diameter is variable like the driving pulley 22, and its central axis is output by another power transmission member 36.

And the drive pulley 22 is connected to the driven pulley 34 and the belt 32 to transmit power, and the outer diameter thereof is variable to perform a shifting action, Figure 2 is an embodiment to enable it An example configuration is shown.

That is, the driving pulley 22 is composed of the fixed side pulley 38 and the variable side pulley 40, the fixed side pulley 38 is formed integrally with the power transmission member 24, the variable side pulley 40 ) Is configured to be coupled to the power transmission member 24 and the ball spline 48 to move in the axial direction.

A casing member 42 is provided on the side of the variable side pulley 40 to form a hydraulic chamber 44 therebetween, and the hydraulic chamber 44 passes through a flow passage 46 formed in the power transmission member 24. The pressure fluid generated by the driving force of the engine can be supplied.

And the driven pulley 34 is made of a fixed side pulley 50 and a variable side pulley 52 as described above, the fixed side pulley 50 is formed integrally with the power transmission member (36).

In addition, the variable side pulley 52 is coupled to the ball spline 54 to move left and right on the power transmission member 36, the variable side pulley 52, the casing member 56 is interposed, the hydraulic chamber 58 ), And the hydraulic fluid 58 can be supplied with a pressure fluid generated by the driving force of the engine through the flow path 60 formed in the power transmission member 36.

Of course, the configuration of the driving and driven pulleys 22 and 34 is not limited to the above configuration, and includes all that can be easily invented from the configuration.

The longitudinal transmission gear device 62 is connected to the power transmission member 36 of the driven pulley 34, and the longitudinal reduction gear device 62 is disposed on the power transmission member 36 connected to the driven pulley 34. Drive gear 62 which is fixedly coupled to one side circumference and the drive gear 62 is coupled to the driven gear 64 and the central shaft 66 of the driven gear 64 to receive power to transfer power Another drive gear 68 and another drive gear 68 is made up of a differential device 70 for power transmission.

In addition, the differential device 70, as is known, is disposed on the left and right sides inside the case, a pair of side gears coupled to the drive shaft on which the driving wheels are mounted at both ends, and a pair of pinions engaged between the front and rear sides of the side gears. Is done.

According to the present invention, the continuously variable transmission includes the input of any one of the three elements of the planetary gear set according to the presence or absence of the operation of the friction elements selected by the transmission control unit and the other element. By selecting as the reaction force element, the following ratios of forward speed and reverse speed are output.

The range-specific operation table relating to the friction elements for which operation and non-operation are selected by the transmission control unit is shown in FIG. 3.

FIG. 4 is a graph for explaining the speed ratio when the shift is made while the friction element of the compound planetary gear device of the continuously variable transmission is controlled as shown in the operating element table using a lever analysis method, and the left end of the lever L is a double pinion. A first node Nl in which the sun gear 16 on the side is present, a second node N2 in which the double pinion carrier 18 is present, and an adjacent position are ring gears. 21 denotes a third node N3, and the right end is denoted by a fourth node N4 in which the sun gear 26 on the single pinion side exists.

First, the forward (D) speed operates the friction element C1 connected to the sun gear on the single pinion side to lock the long pinion 19.

Accordingly, while the first node N1 corresponding to the sun gear 26 on the single pinion side becomes the fixed end, the fourth node N4 corresponding to the sun gear 16 on the double pinion side becomes the input element and the fourth node N4. Is obtained by connecting the first node Nl with a straight line L2 at an arbitrary position of the speed input line L1, and connecting the straight line L2 with the second node N2 serving as an output terminal in a vertical direction. The line becomes the forward output speed line L3.

The driving force of the engine obtained by the forward output speed line is the rotational power is input through the drive pulley 22 and transmits the rotational power to the driven pulley 34 through the belt 32.

In addition, the rotational power of the double pinion carrier 18 is increased or decreased in the rotational speed through the change of the outer diameter of the driving and driven pulleys 22 and 34. The conversion condition thereof is, firstly, the driving pulley 22 and the driven pulley. Second, the outer diameter of the driving pulley 22 is larger than the diameter of the driven pulley 34 and third, the diameter of the driving pulley 22 is smaller than the diameter of the driven pulley 34. It can be divided into cases.

In the first condition, when the outer diameters of the driving and driven 22 and 34 are the same, the transmission ratio is 1: 1.

And secondly, when the outer diameter of the driving pulley 22 is larger than the diameter of the driven pulley 34, the rotation speed of the driven pulley 34 becomes larger than the rotation speed of the driving pulley 22, so that the speed is increased. When the outer diameter of 22 is smaller than the diameter of the driven pulley 34, the rotation speed of the drive pulley 22 becomes smaller than the rotation speed of the driven pulley 34, thereby decelerating.

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

The change in the outer diameter of the driving pulley 22 and the driven pulley 34 is determined by the hydraulic pressure supplied to the hydraulic chambers 44 and 58, and such hydraulic control is usually used in a continuously variable vehicle. It will be possible to use the system, so a detailed description thereof will be omitted.

At the reverse speed, the brake means Bl is operated to release the friction element C1 and to make the ring gear 21 a reaction force element.

Then, the third node N3 corresponding to the ring gear 21 becomes the fixed end, and the fourth node N4 corresponding to the sun gear 26 on the double pinion side becomes the input end, and thus the speed of the fourth node N4. The line obtained by connecting the third node N3 and the straight line L4 at an arbitrary position of the input line Ll, and connecting the straight line L / 1 and the second node N2 which becomes the output terminal in a vertical downward direction The reverse output speed line L5 is obtained.

The reverse output speed obtained as described above operates in the same manner as described in the forward speed while passing through the continuously variable transmission means, and thus the reverse speed is omitted, and redundant description is omitted.

After the shift is made through the continuously variable transmission means 20 as described above, deceleration is made through the longitudinal reduction gear device 62, and power is transmitted through the differential device 70, such that forward and backward driving are performed. Will be.

In the continuously variable transmission for a vehicle of the present invention, the speed of the engine is decelerated by the deceleration means at the time of the forward and the reverse to be input to the drive pulley of the continuously variable transmission means, thereby improving the power transmission efficiency of the belt pulley, and thus the slope At the start of the vehicle can be started without slipping.

Claims (6)

A torque converter 4 for converting torque by receiving power from an engine, and an input shaft 12 directly connected to the turbine 8 side of the torque converter 4, and a double pinion planetary gear device and a single pinion planetary gear. Deceleration means (14) which consists of a compound planetary gear device in which the devices are arranged in parallel and controls forward and backward by determining the forward and backward directions of the vehicle and outputs rotational power, and decelerates the rotational force of the engine by the driving pulley 22. And the stepless speed change means 20 and the stepless speed change means 20 which receive the rotational power output from the deceleration means 14 to the belt 32 and perform stepless speed change according to the rotation speed input from both sides. A continuously variable transmission for a vehicle comprising a longitudinal deceleration gear device 62 for outputting the longitudinally reduced rotational power. 2. The deceleration means according to claim 1, wherein the deceleration means is provided with the sun gear 16 of the double pinion planetary gear set always directly connected to the input shaft to act as an input element, and the double pinion carrier 17 of the double pinion planetary gear set is connected to the driving pulley 22. Connected to act as an output element at all times, so as to selectively maintain the long pinion 19 and the locking state via the friction element C1 between the sun gear 26 and the transmission case 28 of the single-pinion planetary gear set. And a stepless transmission for a vehicle to selectively act as a reaction force element through the brake means (Bl) between the outer side of the ring gear (21) and the transmission case (28). 3. The continuously variable transmission for vehicle according to claim 2, wherein the friction element (C1) is made of a multi-plate clutch. 3. The continuously variable transmission for vehicle according to claim 2, wherein the brake means (Bl) is made of a band brake. The method according to claim 1, wherein the continuously variable transmission means (20) is mounted to the outer periphery of the power transmission member (24) connected to the double pinion carrier (18) and to the driving pulley (22) and the driving pulley (22) of which the outer diameter is variable. The belt 32 includes a driven pulley 34 which is formed to be variable in outer diameter and drives another power transmission member 36 arranged side by side at a predetermined distance apart from the power transmission member 24. A continuously variable transmission for a vehicle. According to claim 1, the longitudinal reduction gear device 62 is meshed with the drive gear 62 and the drive gear 62 is fixedly coupled to one outer periphery on the power transmission member 36 connected to the driven pulley (34). Power is transmitted through another drive gear 68 and another drive gear 68 connected to the driven gear 64 and the central shaft 66 of the driven gear 64 to transmit power. A continuously variable vehicle for speed consisting of a differential device 70 made of.