KR20170039796A

KR20170039796A - Method for learning touch point of clutch for vehicles

Info

Publication number: KR20170039796A
Application number: KR1020150138552A
Authority: KR
Inventors: 이호영; 김진성
Original assignee: 현대자동차주식회사
Priority date: 2015-10-01
Filing date: 2015-10-01
Publication date: 2017-04-12
Also published as: KR101755851B1

Abstract

The present invention relates to a method for learning a touch point of a clutch for a vehicle, which can learn a touch point in a driving situation in which a gear is pre-engaged with a non-drive shaft, and comprises: a slip inducement step of inducing a slip while gradually increasing clutch torque in a clutch arranged in the non-drive shaft when the gear is pre-engaged with the non-drive shaft; a vibration component detection step of detecting a vibration component with a wheel speed and an input shaft speed in a process of inducing the slip; and a learning step of learning a clutch position of the non-drive shaft with a touch point value when the detected vibration component value is higher than a reference value.

Description

[0001] METHOD FOR LEARNING TOUCH POINT OF CLUTCH FOR VEHICLES [0002]

The present invention provides a method of learning a touch point of a vehicle clutch capable of learning a touch point in a situation where gears are accumulated on a non-driving shaft.

The automatic manual transmission is a system that automatically controls the transmission based on a manual transmission mechanism. Unlike an automatic transmission using a torque converter and a wet multi-plate clutch, a dry clutch is used to transmit engine torque.

Particularly, the dry clutch has a characteristic that the clutch transmission torque greatly changes according to various factors such as wear tolerance due to individual component tolerances and durability of the components, thermal deformation due to high temperature, and change of friction coefficient of the disk, Estimation of torque is difficult.

Therefore, if the change of the transmission torque during the clutch control is not known, an excessive slip of the clutch may occur or an impact may be caused. Therefore, an algorithm for predicting the torque characteristic of the dry clutch in real time is needed.

Conventionally, the transmission torque characteristic and the touch point of the clutch are predicted through the micro-slip control of the clutch that predicts the transmission torque map (Torque-Stroke Curve: T-S curve) of the dry clutch in real time. Here, the TS curve is a curve obtained by data of the transmission torque characteristic of the dry clutch according to the stroke of the clutch actuator, and the touch point indicates the position of the clutch actuator at the time when power is transmitted to the clutch on the TS curve .

Especially, in the case of the touch point, when the touch point of the system is not known as an important factor of the clutch transmission characteristic, the drivability accompanied by an impact at the time of oscillation and low speed traveling is deteriorated. Since the touch point varies depending on the temperature and the centrifugal force, it is necessary to check the touch point at all times in the system.

Conventionally, learning is carried out on the touch point in a state where the gear is not engaged with the non-drive shaft during stopping.

In other words, when the clutch speed of the non-drive shaft falls freewheeling, when the clutch torque is applied to the throttle, there occurs a point where the acceleration of the shaft changes. Since the change of the acceleration means that the power starts to be transmitted by the clutch, You can check the starting point by touch point.

However, when the vehicle travels at a high speed, since the non-drive shaft gear is engaged and waited while driving to improve the shift performance, the conventional touch point learning method has a problem that it is difficult to confirm the touch point by using the non- .

It should be understood that the foregoing description of the background art is merely for the purpose of promoting an understanding of the background of the present invention and is not to be construed as an admission that the prior art is known to those skilled in the art.

JP 2015-102241 A

SUMMARY OF THE INVENTION The present invention has been made in order to solve the conventional problems as described above, and it is an object of the present invention to provide a method of learning a touch point of a vehicle clutch capable of learning a touch point in a running situation in which gears are accumulated on a non-

According to another aspect of the present invention, there is provided a slip induction method for inducing a slip while gradually increasing a clutch torque to a clutch disposed on a non-drive shaft when gears are preliminarily stacked on a non-drive shaft. A vibration component detecting step of detecting a vibration component using the wheel speed and the input shaft speed in the process of inducing the slip; And a learning step of learning the clutch position of the current non-drive shaft as a touch point value when the detected vibration component value exceeds a reference value.

In the slip induction step, the slip of the non-driving shaft clutch is less than a predetermined level, so that the slip can be induced within a range in which the vibration of the clutch can occur.

Wherein the vibration component detecting step includes: a reference speed generating step of generating a virtual target input shaft speed from the wheel speed; And a vibration recognition step of detecting a vibration component by a difference between the actually measured input shaft speed and the virtual target input shaft speed.

In the vibration recognition step, the vibration component may be detected by processing the difference between the actually measured input shaft speed and the virtual target input shaft speed using a high pass filter.

Further comprising a driving state determining step of determining whether to enter the slip inducing step according to a driving state of the vehicle before the slip inducing step; The driving state of the vehicle determined in the driving state determination step may include a state in which the gear is engaged with both the driving shaft and the non-driving shaft, the power of the engine is transmitted through the driving shaft clutch, .

According to the present invention, the touch point of the clutch can be detected and learned by using the non-drive shaft even in a high-speed running state in which gears are meshed with both the drive shaft and the non-drive shaft, Thereby improving the transmission feel and driving ability of the vehicle.

1 is a diagram showing the overall structure of a vehicle equipped with a DCT.
2 is a diagram for explaining a learning flow of a touch point learning method according to the present invention.
3 is a view for explaining a configuration of a vibration component detector applied to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The method of learning a touch point of a vehicle clutch of the present invention may include a slip inducing step, a vibration component detecting step, and a learning step.

Referring to FIG. 1, in detail, in a slip induction step, when gears are preliminarily stacked on a non-drive shaft, slip can be induced while gradually increasing the clutch torque to the clutch disposed on the non-drive shaft .

In the vibration component detecting step, the vibration component can be detected using the wheel speed and the input shaft speed in the process of inducing the slip.

Next, in the learning step, when the detected vibration component value is equal to or greater than the reference value, the clutch position of the current non-drive shaft can be learned as the touch point value.

In this case, the sleep inducing step may further include a driving state determining step of determining whether to enter the sleep inducing step according to the driving state of the vehicle before the sleep inducing step.

For example, the driving state of the vehicle determined in the driving state determination step may be a state in which the gear is engaged in both the driving shaft and the non-driving shaft, and when the vehicle is traveling with the power of the engine being transmitted through the driving shaft clutch You can enter.

Here, the drive shaft may be an input shaft that transmits the driving force of the engine to the output shaft through a clutch that is engaged among the two dry clutches mounted on the DCT, and the non-driving shaft is connected to the remaining clutch, And may be an input shaft that does not directly transmit driving force.

1, the drive shaft and the non-drive shaft are denoted by reference numerals INPUT1 and INPUT2, respectively. The clutch disposed on the drive shaft is indicated by CL1 and the clutch disposed on the non-drive shaft is indicated by CL2. It is noted that the clutch actuators applying the clutch torque to the drive shaft clutch are denoted by CLA1 and CLA2, respectively. However, the drive shaft and the non-drive shaft may be interchanged according to the currently engaged gear stage.

That is, when the vehicle is driven at a high speed in a state where the gear is coupled to the drive shaft and the clutch disposed on the drive shaft is engaged, the gear provided on the non-drive shaft also becomes a pre-combination state.

In this state, the clutch actuator CLA2 applies the clutch torque to the clutch disposed on the non-drive shaft in the direction of gradually increasing the speed to induce the slip of the non-drive shaft clutch. In the slip process, the vibration component detector 1 is used And detecting the time when the vibration component value exceeds the reference value, the non-drive shaft clutch position at the detected time point can be detected and learned as the touch point value.

According to the above configuration, the present invention can detect and learn the touch point of the clutch using the non-drive shaft even in a high-speed running state in which gears are meshed with both the drive shaft and the non-drive shaft, The transmission feeling and the driving performance of the vehicle can be improved.

In the present invention, in the slip induction step, the slip of the non-drive shaft clutch is less than a predetermined level, so that the slip can be induced within a range in which the vibration of the clutch can be generated.

That is, when the clutch torque is gradually applied to the clutch provided on the non-driving shaft to reach the vicinity of the touch point, it is not enough for the occupant to feel, but the slip Lt; / RTI >

In the present invention, the vibration component detecting step may include: a reference speed generating step of generating a virtual target input shaft speed from the wheel speed; a vibration detecting step of detecting a vibration component by a difference between the actually measured input shaft speed and the virtual target input shaft speed Step.

In the vibration recognition step, the difference between the actually measured input shaft speed and the virtual target input shaft speed may be processed by the high pass filter 5 to detect the vibration component.

That is, the input shaft speed sensor IS calculates the speed of the input shaft that provides power to the present wheel by multiplying the speed ratio of the transmission gear currently engaged with the speed signal input from the vehicle's wheel speed sensor Ws by the longitudinal speed reduction ratio, The drift component can be removed and the vibration component value can be detected as a reference of the input shaft speed by processing the difference of the input shaft speed inputted from the input shaft speed by the high pass filter 5. [

For example, before the non-drive shaft slips, the vibration due to the difference between the input shaft speed calculated based on the wheel speed sensor Ws and the input shaft speed measured by the input shaft speed sensor IS has a relatively low frequency band, At the time when the clutch vibrates due to the slip of the clutch, the high-pass filter 5 switches to a vibration component of a relatively high frequency band, preferably a frequency exceeding the reference value, .

Therefore, it is possible to detect the clutch position at the point of time when the high frequency equal to or higher than the reference value is detected as the touch point value, and update it with the touch point.

Here, the vibration component detection according to the present invention can be detected through the vibration component detector 1 shown in Fig.

For example, the vibration component extractor includes an integration unit 3 for multiplying the wheel speed by the transmission ratio and the longitudinal reduction ratio to obtain the rotation speed of the input shaft related to the current drive, And a high pass filter 5 for calculating the difference of the input shaft speed measured by the high pass filter and processing it by a high pass filter.

Since the vibration component value processed by the high pass filter 5 can be input to the control unit 7, the control unit 7 can detect and learn the touch point by comparing the vibration component value and the reference value .

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limited to the specific embodiments set forth herein; rather, .

1: Vibration component detector 3:
5: High pass filter 7:

Claims

A slip inducing step of inducing a slip while gradually increasing a clutch torque to a clutch disposed in the non-driving shaft when the gear is preliminarily stacked on the non-driving shaft;
A vibration component detecting step of detecting a vibration component using the wheel speed and the input shaft speed in the process of inducing the slip; And
And learning the clutch position of the current non-drive shaft as a touch point value when the detected vibration component value exceeds a reference value.

The method according to claim 1,
Wherein the slip inducing step induces a slip in a range in which the slip of the non-driving shaft clutch is less than a predetermined level so that vibration of the clutch can occur.

The method according to claim 1,
Wherein the vibration component detecting step comprises:
A reference speed generating step of generating a virtual target input shaft speed from the wheel speed;
And detecting a vibration component by a difference between an actually measured input shaft speed and the virtual target input shaft speed.

The method of claim 3,
Wherein the vibration recognition step detects a vibration component by processing a difference between an actually measured input shaft speed and the virtual target input shaft speed using a high pass filter.

The method according to claim 1,
Further comprising a driving state determining step of determining whether to enter the slip inducing step according to a driving state of the vehicle before the slip inducing step;
The driving state of the vehicle judged by the driving state judging step is a state in which the gear is engaged with both the driving shaft and the non-driving shaft, the power of the engine is transmitted through the driving shaft clutch, Wherein the touch point learning method comprises: