EP1485643A2

EP1485643A2 - Twin-clutch transmission and method for controlling and/or regulating a twin-clutch transmission during an overlapping gearshift

Info

Publication number: EP1485643A2
Application number: EP03714665A
Authority: EP
Inventors: Jürgen BENZ
Original assignee: LuK Lamellen und Kupplungsbau Beteiligungs KG; LuK Lamellen und Kupplungsbau GmbH
Current assignee: Schaeffler Buehl Verwaltungs GmbH; LuK Lamellen und Kupplungsbau GmbH
Priority date: 2002-03-07
Filing date: 2003-02-28
Publication date: 2004-12-15
Also published as: WO2003074908A2; FR2836975A1; DE10390916D2; AU2003218940A1; WO2003074908A3

Abstract

The invention relates to method for controlling and/or regulating a twin-clutch transmission during an overlapping gearshift, whereby at least one clutch is controlled in such a manner that a clutch is slip-controlled. The invention also relates to a twin-clutch transmission for a vehicle, especially for carrying out the method, whereby at least one control device for controlling and/or regulating at least one clutch during an overlap phase is provided.

Description

Double clutch transmission and method for controlling and / or regulating a double clutch transmission in an overlap shift

The invention relates to a double clutch transmission and a method for controlling and / or regulating a double clutch transmission in an overlap shift.

Double clutch transmissions and methods for controlling and / or regulating a double clutch transmission in an overlap shift are known from vehicle technology. For example, it can be provided in a parallel shift transmission that the engine torque is changed by the internal combustion engine of the vehicle in order to compensate for inaccuracies in the moments of the components involved.

The problem here is that the internal combustion engine cannot be controlled so precisely and, above all, not so quickly that inaccuracies in the overlap circuit can be compensated for in a relatively short time.

The invention is therefore based on the object of proposing a dual clutch transmission and a method for controlling and / or regulating a dual clutch transmission in an overlap shift, so that shifting without engine intervention is possible, which are particularly robust against torque errors of the clutches.

In terms of the method, this object is achieved by a method for controlling and / or regulating a double clutch transmission in an overlap shift, in which at least one clutch is controlled in such a way that slip control is carried out on a clutch. In the proposed strategy, the part of the overlap phase is preferably taken into account until the clutch of the target gear has completely taken over the torque. It is particularly advantageous in the method according to the invention that the clutch can generally react faster to target requirements than the internal combustion engine. Furthermore, in contrast to the internal combustion engine (due to full load), the couplings are at high Moments not limited. Furthermore, the method according to the invention enables only a torque desired by the driver to act on the output when the control is stable. Advantageously, no engine intervention is required in the strategy according to the invention.

According to a further development of the invention, it can be provided that the clutch of the target gear keeps the slip or the slip speed at the clutch of the old gear as constant as possible with the engine torque unaffected, ie without engine intervention. It is also possible for the control to be implemented with the opening clutch and / or with both clutches.

In the proposed method, a slip control of the control of the new clutch assigned to the target gear can preferably be superimposed during the overlap phase. For example, through the

Using a simple PID controller or the like can be realized. In the method according to the invention, for a sensible regulation, it should be taken into account that the regulation times between the target and the actual specifications lie significantly below the duration of the overlap phase. The duration of the overlap phase can be adapted to the regulation of the clutches in the method according to the invention.

Furthermore, according to a development of the invention, it can be provided that the torque of the new clutch assigned to the target gear is regulated during the specification of the engine torque and the torque of the old clutch assigned to the starting gear. For example, the engine torque can be specified by the driver's desired torque, the following equation applying:

Miviot - driver request The torque at the old clutch assigned to the starting gear can preferably be specified by a starting value, which is changed, for example, by a time-dependent function, the following equation being valid:

When regulating the torque on the new clutch assigned to the target gear, the following equation can apply: Mkupplung_neu = / (t) ~ (M ot_Start ^_ M | yiot) + Mptegler

In a next embodiment, the difference between the engine speed and the speed of the transmission input shaft of the starting gear can be used, for example, as an input variable for the PID controller, in particular during upshifts or the target gear during downshifts. The speed change on the transmission input shafts cannot flow back into the controller due to the clutch torque or the counter torque from the output, such as driving resistance, road gradient or the like. However, the slip can be reduced if the clutch of the target gear is further closed.

To ensure that a sufficient slip reserve or setpoint slip speed is present during the overlap phase, the setpoint slip speed can preferably be built up to the required reserve at the beginning of the overlap. Preferably, the clutch of the old gear z. B. slowly open, and only after reaching the slip reserve, the second clutch associated with the target gear can be closed.

According to a next development of the invention, the slip reserve can preferably be regulated via a time-dependent structure of the target slip speed in such a way that the clutch of the target gear begins to build up the target slip speed relatively early. It is possible for a positive slip to be built up in pull circuits and a negative slip for push circuits. In the strategy according to the invention it can be provided that the engine speed is further brought to the target speed of the new gear in the case of train downshifts or thrust upshifts before the overlap phase begins.

In the method according to the invention, it can preferably be checked at the beginning of the overlap phase whether the clutch assigned to the starting gear is in the slip state. If this is not the case, the torque on the old clutch can be reduced until, for example, the old clutch slips. If the clutch slips, the target slip speed or the slip reserve can then be calculated. The clutches can then be piloted and the controller can regulate the torque of the new clutch until the torque on the old clutch is approximately less than zero. The controller torque can preferably be determined as a function of the target slip speed and / or the gradient of the target slip speed.

The method according to the invention can preferably be used in parallel gearboxes (PSG), but also under certain circumstances in other automated gearboxes.

Furthermore, the object on which the invention is based can be achieved in terms of the device by means of a double clutch transmission for a vehicle, in particular for carrying out the proposed method, at least one control device or the like being provided for controlling and / or regulating at least one clutch during an overlap phase. It is particularly advantageous in the dual clutch transmission according to the invention that the clutch can react faster to target requirements than the internal combustion engine. In addition, in the dual clutch transmission according to the invention, only the torque desired by the driver is transmitted to the output and advantageously no engine intervention is required. Further advantages and advantageous configurations result from the subclaims and the drawings described below. Show it:

FIG. 1 shows a flow diagram of a possible exemplary embodiment of the method according to the invention;

Figure 2 is a schematically illustrated model with acting on a vehicle

moments; and

Figure 3 curves of speeds and moments in a train upshift;

FIG. 1 shows a flow diagram of a possible exemplary embodiment of the method according to the invention.

At the beginning of the process or the overlap phase, it is checked whether the old clutch assigned to the starting gear is in the slip state. If this is not the case, the torque Mk _U p _P _ait on the old clutch is reduced until the clutch slips.

If the clutch slips, a target slip delta_n_soll is calculated so that a function f _n (t) that is dependent on time is obtained. The pilot control of the two clutches is then started, the moment Mku piung_ _a i _t on the old clutch being specified by a start value Mkup iung_ait_start, which is changed by a time-dependent function f (t). The moment M _kUpp _ _neL on the new clutch is determined by the following equation:

Mκupplung_neu = / (t) - (M | viot_Start ~ M ^ ot)

A controller torque M _RΘg ier is preferably determined by a PID controller as a function of the slip speed delta_n and the gradient d (delta_n) / dt of the slip _speed specified until the torque (M _k upp_ait) on the old clutch is less than zero. This means that control of the overlap phase is realized to the point where the old clutch is fully open. The procedure or the overlapping phase is then ended.

In Figure 2, the engine torque M _Mot and the moments on the two clutches Mku _P _new, Mku _PP _ait are illustrated on a model. The inertia mass J _{Mot of} the motor is also indicated.

In Figure 3, the curves of different speeds and moments at one

Train upshift shown, which is divided into a first phase (approach slip limit), a second phase (overlap) and a third phase (synchronization of the target clutch).

In the upper diagram, the engine speed n_Mot with a solid line, the speed n_GE_alt of the transmission input shaft of the old clutch with a dashed line, the speed n_GE_neu of the transmission input shaft of the new clutch with dash-dotted line, the slip speed delta_n with a crossed line and the target slip speed delta_n_soll shown.

The lower diagram shows the engine torque MM _C Λ with a solid line, the torque Mku piung_ait on the old clutch with a dashed line, the torque M _k uppiung_πeu on the new clutch with dash-dotted line and the torque M_kupplung_neu_oR on the new clutch without a regulator.

In order to ensure that there is sufficient slip reserve during the overlap phase, at the beginning of the overlap phase the target slip speed delta_n_soll is first built up to the required reserve, which results from the course of the target slip speed delta_n_soll in the upper diagram from FIG. 3. The activation of the new clutch is illustrated in particular from the torque curve M _kU ppiung_neu of the new clutch, which is shown in is shown in the diagram below. Furthermore, the constant profile of the engine torque Mwiot shows that no engine intervention is carried out in the method according to the invention.

It has been shown that the regulation of the slip also errors in the

Can eliminate clutch torque and keep the slip speed delta_n between 0 and about 200 revolutions / min. The use of the slip control while driving with a partial transmission can also be used for the slip build-up. For this purpose, the slip speed delta_n can preferably be controlled during the overlap phase with the clutch of the old gear.

It is particularly advantageous if no ramp profiles are used in the overlap circuit, but e.g. B. started with a parabolic function or the like and is then changed to a linear course. As a result, the new clutch can slowly come into a work area in which the control times are similar to the old clutch.

The duration of the overlap phase is adjusted in the method according to the invention. For the model of the position controller of the coupling used (τ _PT ι = 50ms) there is a minimum time of approx. 400 to 500ms for the duration of the overlap. However, other values are also conceivable. Furthermore, other measures or combinations of the aforementioned measures are also possible. It is possible that the measures mentioned are modified in order to further improve the strategy according to the invention.

The patent claims submitted with the application are proposals for formulation without prejudice for the achievement of further patent protection. The applicant reserves the right to claim further combinations of features previously only disclosed in the description and / or drawings. Back relationships used in subclaims indicate the further development of the subject matter of the main claim through the features of the respective subclaim; they are not to be understood as a waiver of the achievement of independent, objective protection for the combinations of features of the related subclaims.

Since the subjects of the subclaims can form their own and independent inventions with regard to the prior art on the priority date, the applicant reserves the right to make them the subject of independent claims or declarations of division. They can furthermore also contain independent inventions which have a design which is independent of the objects of the preceding subclaims.

The exemplary embodiments are not to be understood as a restriction of the invention. Rather, numerous changes and modifications are possible within the scope of the present disclosure, in particular such variants, elements and combinations and / or materials, which, for example, by combining or modifying individual ones in conjunction with and described in and in the general description and embodiments and the claims Features or elements or process steps contained in the drawings can be removed by the person skilled in the art with regard to the solution of the task and, by means of combinable features, lead to a new object or to new process steps or process step sequences, also insofar as they relate to manufacturing, testing and working processes.

Claims

claims

Method for controlling and / or regulating a dual clutch transmission in an overlap shift, characterized in that at least one clutch is controlled in such a way that slip control is carried out on a clutch.

A method according to claim 1, characterized in that the clutch of the target gear is controlled without changing the engine torque (M _O ) in order to keep the slip speed (delta_n) at the clutch of the initial gear approximately constant.

A method according to claim i or 2, characterized in that a slip control is superimposed on the control of the clutch of the target gear during the overlap phase.

A method according to claim 3, characterized in that at the beginning of the overlap phase, a slip reserve is built up in which the clutch assigned to the starting gear is slowly opened and the clutch assigned to the target gear is closed after a desired slip speed (delta_n_soll) has been reached.

A method according to claim 4, characterized in that the slip reserve is built up as a function of time, the clutch of the target gear starting relatively early to build up the target slip speed (deta_n_soll).

Method according to one of the preceding claims, characterized in that a PID controller is used to control the clutch.

A method according to claim 6, characterized in that the difference between the engine speed and the speed (n_GE_alt) of the transmission input shaft of the initial gear is used as the input variable for the PID controller.

8. The method according to any one of the preceding claims, characterized in that the duration of the overlap phase is adapted to the regulation of the clutches.

9. The method according to any one of the preceding claims, characterized in that the engine torque (MM _O and the moment (Mku p_ _a ιt) on the old clutch assigned to the starting gear and the torque (Mk _Upp _new) on the new the target gear associated clutch is regulated.

10. The method according to claim 9, characterized in that the engine torque (MM _O by the driver's desired torque (M _Fa stirrer desired) is specified and the following equation applies:

M ot ⁼ M driver request

11. The method according to claim 9 or 10, characterized in that the torque (Mku _PP iung_ait) on the old clutch assigned to the starting gear is predetermined by a start value (Mkuppiung_ait_start) which is changed by a time-dependent function (f (t)), and that the following equation holds:

Mκupplung_alt = Mκupp! Ung_alt_Start ~ / (t)

12. The method according to any one of claims 9 to 11, characterized in that when regulating the torque (Mku _P iung_neu) on the new clutch assigned to the target gear, the following equation applies: Mκupplung_neu = / (t) - (MMot_Start ~ M | viot) + Mptegler

13. The method according to any one of the preceding claims, characterized in that it is checked at the beginning of the overlap phase whether the clutch assigned to the starting gear is in the slip state, if not, the moment

(M _k upp_ait) reduced on the old clutch and if so a target slip speed (delta_n_soll) is calculated, the clutches then being pilot-controlled and then a controller regulates the torque (M _kUpp _new) until the torque (M _kUpp _ait) on the old clutch becomes approximately less than zero.

A method according to claim 13, characterized in that the controller torque (M _R egier) in dependence on the target slip speed (delta_n_soll) and / or

Gradient (d (delta_n) / dt)) of the target slip speed (delta_n_soll) is determined.

Double clutch transmission for a vehicle, in particular for performing the method according to one of claims 1 to 14, characterized in that at least one control device for controlling and / or regulating at least one

Clutch is provided during an overlap phase.