DE102004029076A1 - Controlling clutch in automatic transmission of motor vehicle when changing gears, by increasing clutch torque and controlling reduction in slipping via engagement of engine - Google Patents

Abstract

The clutch torque (Tcl) is increased to re-engage a slipping clutch. The reduction in slipping is controlled via an engagement of the engine. The clutch torque is preferably monotonously increased based on a predetermined function, such as a linear ramp function. An independent claim is included for a control apparatus.

Description

The The present invention relates to a method of driving a clutch in a transmission, in particular an automated transmission, a vehicle in a gear change, in which at least one clutch torque and an engine torque changed becomes. Furthermore, the invention relates to a drive device for a clutch a transmission, in particular an automated transmission, a Vehicle.

Out Vehicle technology is a method for driving a clutch in a transmission, in particular an automated transmission, a vehicle known. In this process, a torque build-up performed after the gear change, when the clutch is complete open is. Furthermore, a drive device is known, which increases the torque realized on the clutch of the transmission.

Of the Invention is based on the object, a method for driving a clutch in a transmission and a driving device of to propose the genus mentioned above to make the gear change more comfortable and perform faster to be able to.

These Task is achieved by a method for driving a clutch in a transmission, in particular an automated transmission, one Vehicle in a gear change, in which at least one clutch torque and an engine torque changed will be solved, by the clutch torque to re-engage in slipping Coupling is increased, and that the slippage reduction controlled solely by a motor intervention becomes.

Further The object underlying the invention by a drive device for one Coupling of a transmission, in particular of an automated transmission, a vehicle, with at least one engine control unit and at least a transmission control unit, in particular for performing of the method according to the invention, solved, which at a gear change with slipping clutch, the engine control unit and / or the transmission control unit such that the clutch torque when re-engaging elevated and slipping down over an engine intervention is performed.

Therefore is with the method according to the invention one possible steady momentum especially after a gear change already realized with slipping clutch, so a buildup of acceleration of the vehicle to the target acceleration without local extremes is possible. It is particularly advantageous in the method that the rules and the grinding of the clutch when re-engaging by the Engine intervention performed becomes. Because as long as the clutch grinds, is by the course the clutch torque determines the wheel torque and thus the comfort. Therefore, the clutch torque should not possible for the scheme and the grinding can be used.

As part of a development of the invention can be provided that the clutch torque (T _cl ) is monotonically increased according to a predetermined function or according to a predefined profile. Particularly advantageous is the use of at least one linear ramp function or the like. For example, several contiguous linear ramp functions can be used. In this way, an optimal shifting comfort for the driver or vehicle occupants can be realized.

One Another advantage of the present invention is that to Beginning of the rejoining process, the clutch is not open has to be. Therefore, the increase in the clutch torque at a value to be started at the end of the shift already was present. This is especially for load circuits z. B. in an ASG3 transmission advantageous.

T_e,d

= Fahrerwunschmoment;

J_e

= Motorträgheitsmoment

w_I

= Drehzahl der Getriebeeingangswelle.

According to a next embodiment of the invention the clutch torque can in a slipping clutch to a maximum to be transmitted clutch torque T _cl, are _within limits, as this is the maximum torque T _{cl, max,} which can be transmitted from the engine directly after coupling to the wheels , The maximum torque T _{cl, max to} be transmitted by the clutch can preferably be determined or calculated according to the following equation: T cl, max = T e, d - J e · (Dw I / Dt) where:

T _{e, d}

= Driver's desired torque;

J _e

= Moment of inertia

w _I

= Speed of the transmission input shaft.

It However, it is conceivable that, in particular for faulty torque determination, in case of too long slip phase or the like an exception to this fixed values becomes.

In the proposed engine intervention for slip control, the engine torque or give the same as the output of a controller. As a controller, preferably a PID controller can be used. The controller used can change the current engine speed to a predetermined engine speed according to an embodiment of the invention. Preferably, a tangential as possible approach to the predetermined engine speed can be realized.

at a particularly simple case design can as a predetermined engine speed the transmission input speed can be used. However, too other default profiles conceivable. For example, it can be used as a condition be provided that the engine target speed is about to stick the clutch is identical to the transmission input speed.

Of the Use of the method according to the invention is particularly advantageous in vehicles with a so-called ASG3 transmission especially in upshifting. However, the procedure may as well in other transmission systems and also in other types of circuits be used.

Further Advantages and advantageous embodiments will be apparent from the dependent claims and the drawing described below.

The single figure of the present invention shows two superimposed shown diagrams, wherein in the upper diagram different Speed curves and indicated in the lower diagram different torque curves are.

In detail, the curves of the engine speed n _E , the transmission input shaft speed n _I and the target speed n _{I, Tgt are shown} in the upper diagram. In the lower diagram, the curves of the engine torque T _E , the requested engine torque T _{E, Req} , the clutch torque T _CL and the clutch _{target torque} T _{CL, Tgt are} shown.

Overall, the torque build-up is shown according to the proposed method, wherein the clutch torque T _{CL is increased} based on a predetermined profile, since the clutch torque T _CL affects the wheel torque as long as the clutch slips. When the clutch is closed, the engine may be used to further slightly increase the speed profile n _{I of} the transmission input shaft. To achieve this, the engine torque T _E should be applied to the torque profile plus the term J _E · ω. _I follow to compensate for the moment which is necessary for the acceleration of the flywheel.

The inventive method is completed when the clutch is closed and the engine torque T _E has reached its final value. However, it is possible that the clutch will also be closed during the ramp function, although a smooth transition is difficult to achieve.

The profile used is a ramp function which is limited in time by the final value of the clutch torque T _CL . The actual course of the clutch torque T _CL follows the dynamic behavior of the clutch system, which is shown in the figure. Furthermore, the value of the clutch _torque T _CL is designated T _kreFill , in which the increase of the clutch torque T _{CL is started} in a so-called ASG3 transmission system. In a normal automated manual transmission ASG, this value is equal to 0 Nm.

Claims (14)

Method for driving a clutch in a transmission, in particular an automated transmission, of a vehicle during a gear change in which at least one clutch torque (T _cl ) and an engine torque is changed, characterized in that the clutch torque (T _cl ) for re-engagement in slipping clutch is increased, and that the slippage reduction is controlled by a motor intervention. A method according to claim 1, characterized in that the clutch torque (T _cl ) is monotonically increased in response to a predetermined function. A method according to claim 2, characterized in that for increasing the clutch torque (T _cl ) at least one linear ramp function is used. Method according to one of the preceding claims, characterized in that the increase of the clutch _torque (T _cl ) at a value (T _kreFill ) is started, which is present at the end of the gear change on the clutch. Method according to one of the preceding claims, characterized in that the clutch torque (T _cl ) is limited in slipping clutch to a maximum to be transmitted clutch torque (T _{cl, max} ). A method according to claim 5, characterized in that the maximum clutch torque (T _{cl, max} ) is calculated by the following equation: T cl, max = T e, d - J e · (Dw I / Dt) where T _{e, d} = driver's desired torque; J _e = engine moment of inertia ω _I = rotational speed of the transmission input shaft Method according to one of the preceding claims, characterized in that the engine torque (T _E ) results in the engine intervention as the output variable of a controller. Method according to claim 7, characterized in that that a PID controller is used as controller. A method according to claim 7 or 8, characterized in that in the controller, the respective current engine speed (n _E ) is brought to a predetermined engine speed (n _{E, Tgt} ). A method according to claim 9, characterized in that a possible tangential approach to the predetermined engine speed (n _{E, Tgt} ) is used. A method according to claim 9 or 10, characterized in that as the predetermined engine speed (n _{E, Tgt} ), the transmission _input speed (n _I ) is used. Method according to one of claims 9 to 11, characterized in that the predetermined engine speed (n _{E, Tgt} ) is selected such that the engine speed (n _E ) shortly before the adhesion of the clutch with the transmission _input speed (n _I ) is identical. Method according to one of the preceding claims, characterized characterized in that it is carried out at Zughochschaltungen. Control device for a clutch of a transmission, in particular an automated transmission, a vehicle, with at least one engine control unit and at least one transmission control unit, in particular for carrying out the method according to one of claims 1 to 13, characterized in that in a gear change in slipping clutch, the engine control unit and / or the transmission control unit are driving bar so that the clutch torque (T _cl ) increases when re-engaging and the slip reduction is controlled by a motor intervention.