DE19939334A1 - Method for shifting double-clutch gearbox without tractive force interruption has two lay shafts connected to output shaft through shiftable gear stages and associated with friction clutch for connection to drive motor - Google Patents

Abstract

The double clutch gearbox contains two lay shafts (V1, V2) connectable to an output shaft (20) through shiftable gear stages (1-6). Each lay shaft is associated with a friction clutch (K1, K2) through which it is connectable to a drive motor (12). The shifting processes are by controlling and/or regulating the clutches and drive motor. For up-changes in drive mode and/or down-changes in coast mode from the time when the clutch transfers no more torque and the clutch of the target gear is in the sliding state the torque of the drive motor is regulated so that the speed of the drive motor is adapted to the changed gear ratio and at the end of this adaption the clutch moves from sliding state to adhesive state.

Description

The invention relates to a method for switching a Dual clutch transmission and a dual clutch transmission according to the patent claims.

A method for shifting a dual clutch transmission and a double clutch transmission of this type are known from DE 196 31 983 C1 known. The dual clutch transmission has two Countershafts and an output shaft. Any countershaft a friction clutch is assigned. In the initial state before one Gear change transmits one of the two clutches in the locked state an engine torque and the other clutch is open. The The countershaft of the other clutch can be set to synchronous speed brought with a switching element, then a new one Gear can be engaged. When changing gears, one Coupling opened by a slip regulator as far as regulated, that they at a target speed of their engine half the sliding limit works, the other clutch is controlled closed until one, by the slip regulator on the Clutch operated clutch no longer transmits a moment. Then the clutch is fully opened, so that only the other clutch transmits the engine power. After that the old gear removed without a moment.

The object of the invention is to be achieved, negative Effects of switching operations on the longitudinal dynamics of the Avoid vehicle.  

This object is achieved according to the invention characterizing features of the claims by regulated Intervention on the engine control solved.

Advantageous developments of the invention are in the Subclaims included.

The invention will now be described with reference to the drawings using preferred embodiments as examples described. The drawings show:

Fig. 1 shows schematically a dual clutch transmission having a control and regulating device according to the invention,

Fig. 2 is a timing diagram of torques and speed characteristics of the dual clutch transmission during the upshift in traction, hereinafter called traction upshift from a lower gear to a higher gear,

Fig. 3 is a timing diagram of transmission output torque during the Zughochschaltens according to Fig. 2,

Fig. 4 is a timing diagram of torques and rotational speed curves during a downshift in the coasting mode, hereinafter called push downshift from a higher gear to a lower gear,

Fig. 5 is a timing diagram of the transmission output rotational torque during the push downshift of Fig. 4,

Fig. 6 is a timing diagram of torques and rotational speed profiles during the pulling downshift, ie a downshift from a higher gear to a lower gear in the traction mode,

Fig. 7 is a timing diagram of transmission output torque during the traction downshift as shown in FIG. 6,

Fig. 8 is a timing diagram of torques and rotational speed profiles during an overrun upshift, ie an upshift, during coasting operation, from a lower gear to a higher gear,

Fig. 9 is a timing diagram of transmission output torque during the overrun upshift in FIG. 8.

Dual clutch transmissions are powershift transmissions. This means that they are without interruption in traction are switchable. Here comes the control and regulation of the two clutches K1 and K2 are of central importance because during the transition from a source aisle to a target aisle both Couplings are engaged at the same time. Mean here The "original gear" is the "original gear" and the "target gear" is the gear to be engaged afterwards. Due to the clutch overlap, d. H. simultaneous torque transmission through both clutches during the gear change, the dual clutch transmission unites the known advantages of a manual transmission, d. H. higher Efficiency and simple structure, with the advantages of one Automatic transmission, d. H. no interruption of traction at the Switching operations.

Fig. 1 shows schematically the structure of a double clutch transmission. The drive torque of a motor vehicle drive motor 12 is transmitted to the two clutches K1 and K2 via a drive shaft 14 and two constant gear stages 16 and 18 . The outputs of the two clutches K1 and K2 are each connected to a countershaft V1 or V2. Here, the first countershaft V1, for example, the odd gears 1, 3 and 5 and the second countershaft V2, for example, the even gears 2, 4 and 6 are assigned. Of course, a different number of gears and a different assignment is also possible. During the constant travel of the motor vehicle, the drive torque of the drive motor 12 is transmitted to an output shaft 20 only via one of the two clutches K1 or K2 and via one of six shift elements S1, S2, S3, S4, S5 and S6.

One of the shift elements S1 to S6 is assigned to each gear. Furthermore, each gear contains a gear stage consisting of at least two gearwheels, one of which is arranged on its shaft in a rotationally fixed manner (fixed gear) and the other is freely rotatable on its shaft (idler gear), the idler gear being rotatably connected to its shaft by the shifting element in question. The switching elements S1 to S6 are rotated on their shaft, but axially displaceable. In the embodiment according to FIG. 1, the shift elements S1, S3 and S5 of the odd gears 1, 3 and 5 and their idler gears 31 , 33 and 35 are on the first countershaft V1; the shift elements S2, S4 and S6 of the even gears 2, 4 and 6 and their idler gears 32 , 34 and 36 on the second countershaft V2; and the associated fixed wheels 21 , 22 , 23 , 24 , 25 and 26 arranged on the output shaft 20 . In one, several or all gears, however, the arrangement can also be interchanged such that the fixed gear in question is or are arranged on the countershaft V1 or V2 and the associated idler gear with its shifting element on the output shaft 20 . The countershafts V1 and V2 are spaced parallel to each other and parallel to the output shaft 20 , so that the clutches K1 and K2 are also arranged parallel to each other. According to another embodiment, as is known from DE 196 31 983 C1, the countershafts V1 and V2 and their clutches K1 and K2 can be arranged axially one behind the other or coaxially one inside the other. The two clutches K1 and K2 are friction clutches. They can also be replaced by other clutches or clutch arrangements, by means of which torque can alternatively be transmitted simultaneously via one or the other or both countershafts V1 and V2.

The double clutch transmission can be designed for semi-automatic or fully automatic operation. In semi-automatic operation, the driver triggers by actuating a switching element, e.g. B. an up-down tip switch actively a gear change, while in the fully automatic mode a higher-level electronic control and regulating device 50 triggers the gear change. In both cases, the switching elements S1 to S6 and the two clutches K1 and K2 are actuated by actuators. The actuators are the actuators of the higher-level controls and regulations of the control and regulating device 50 .

The switching strategy described below applies especially concerns a semi-automatic operation but also fully automatic operation in the same way. The invention relates in particular to control and regulation the overlapping functions of the two Couplings K1 and K2 for both operating modes.

In the known methods, the temporal overlap of the torque transmission of the two clutches K1 and K2 is carried out in a purely controlled manner or, in accordance with DE 196 31 983 C1, one of the two clutches is regulated by a slip controller while the other clutch is controlled. The invention described below is characterized by a special slip control of the clutches K1 and K2 for their overlapping functions. The slip control according to the invention avoids a shift jerk during the overlapping of the slip operation of both clutches K1 and K2. In addition, the entire transition of the torque transmission from one to the other of the two clutches K1 and K2a can be set priori, that is to say can be defined in advance in the control and regulating device 50 . This is not possible with a pure control.

The invention is illustrated in the following examples with reference to 1st gear and 2nd gear described, however, is not limited to this.  

Figs. 2 and 3 show the example of a traction upshift from the first speed "1st" in the second gear "2nd". Before the functional overlap of the two clutches K1 and K2 begins, the clutch of the source gear, here the first clutch K1, is closed, the shift element S1 of the first gear (source gear) establishes a positive connection from the first countershaft V1 to the output shaft 20 . The clutch of the target gear, here the second clutch K2, is open and the shift element S2 of the second gear (target gear) connects the second countershaft V2 to the output shaft 20 via the gear stage 32 , 22 of the second gear. The drive motor 12 generates a drive torque at the transmission input, ie on the drive shaft 14 , which is approximately proportional to the respective position of an accelerator pedal (accelerator pedal). The actual overlap of the couplings essentially takes place in three steps, whereby the individual steps can also overlap.

Fig. 2 shows an example of the progression of the angular velocity ωAM of the drive motor 12, the clutch torques TK1 (t) and TK2 (t) of the first clutch K1 and the second clutch K2 and the IC engine torque TV (t) of the drive motor 12 at a traction upshift, ie with an upshift in train operation (engine pulls the vehicle).

According to the equation

The drive torque TAM (t), which the drive motor 12 delivers to the drive shaft 14 of the transmission, is composed of the engine torque TV (t), the drag torque TSCH (t) and the respective change in the rotational energy. In this equation, JAM is the moment of inertia of the drive motor 12 including the parts connected to it (constant stages 14 , 16 , 18 and other parts).

In the first step, a slip controller of the control and regulating device 50 is activated from a first point in time t1, which controls the first clutch K1 (clutch of the source gear) with the aid of an actuator (actuator) AK1 so that a differential speed of, for example, in this first clutch K1 0.5 U / s to 2 U / s arises. As a result, the angular velocity ωAM of the drive motor increases between the first two times t1 and t2 by a value corresponding to this differential speed. This differential speed or the corresponding value of the increase in the angular speed of the drive motor forms a setpoint for the control by the slip controller. In the second step, the second clutch K2 (clutch of the target gear) is closed from the second point in time t2 and initially operated in the sliding state. For this purpose, the closing pressure of the second clutch K2 is increased linearly in a controlled manner by its actuator AK2. Here, the slip controller of the control and regulating device 50 remains active from the first step, ie it regulates the differential speed of the first clutch K1 and thus also the angular velocity ωAM of the drive motor 12 in accordance with the specified target value. Since more and more torque is transmitted through the second clutch K2 during the second step, the slip regulator continues to decrease the closing pressure of the first clutch K1 until this first clutch K1 is finally fully opened. At this third time t3, the entire drive torque TAM of the drive motor is transmitted via the second clutch K2. At this third time t3, however, the angular velocity ωAM of the drive motor 12 still approximately corresponds to the transmission ratio of the first gear. In the third step from the third point in time t3, the motor angular velocity ωAM must now be reduced.

In this third step, the speed ωAM (t) of the drive motor 12 must therefore be reduced in accordance with the changed gear ratios (i1 / i2) until the second clutch K2 changes from the sliding state to the holding state. Ideally, the clutch torque TK2 of the second clutch K2 is kept constant from the third point in time t3. Now a speed controller of the control and regulating device 50 is activated, which by intervention in the control electronics of the control and regulating device 50 , for. B. Control of a throttle valve of the drive motor, the internal combustion engine torque TV so that the angular velocity ωAM (t) of the drive motor 12 assumes the desired time profile according to FIG. 2.

According to FIG. 2, the first clutch K1 is in the sliding state from the first point in time t1 to the third point in time t3, previously completely closed in the state of detention and then completely open. The second clutch K2 is fully open by the second point in time t2, from the second point in time to the third point in time t3 and from the third point in time t3 to the fourth point in time t4 in the sliding state and then in the state of detention. The sliding state of the first clutch K1 keeps the angular velocity ωAM of the drive motor 12 between the first two times t1 and t2 and between the second and third times t2 and t3 at the desired value. Due to the sliding state of the second clutch K2 between the third and fourth times t3 and t4, the angular velocity ωAM of the drive motor 12 is reduced in accordance with the changed gear ratios from the first gear to the second gear (i1 / i2). This prevents a shift jerk in the longitudinal direction of the vehicle from occurring during the shifting process.

If the desired course of the angular velocity ωAM (t) cannot be set by intervening in the motor control of the control and regulating device 50 because the motor speed has reached limit values upwards or downwards, the control and regulating device 50 can intervene in the Control of the two clutches K1 and K2 change the drive torque TAM acting on the transmission and in this way set the desired profile of the angular velocity ωAM (t) of the drive motor. This is shown, for example, in FIGS . 8 and 9 for a thrust upshift. Here the engine speed is reduced by regulated clutch sliding operation of clutch K1 or K2 of the source gear before the clutch overlap takes place. In the case of a train downshift, the engine speed is increased by clutch-sliding operation of the clutch (K1 or K2) of the source gear before the clutch overlap takes place. There is a risk that clutch interventions can have a negative effect on the longitudinal dynamics of the vehicle.

In the drawings, "T" means torque. TV is the drive torque or, in the case of an internal combustion engine, the internal combustion engine torque of the drive motor 12 . TK1 is the torque transmitted by the first clutch K1. TK2 is the torque transmitted by the second clutch K2.

Fig. 3 shows the idealized transmission output torque TAB on the output shaft 20 as a function of "t" time. The times t1, t2, t3 and t4 correspond to those in FIG. 2. As already mentioned, during the second step between the second time t2 and the third time t3, the input torque of the drive motor 12 is transferred from the first clutch K1 to the second clutch K2 relocated. This reduces the transmission output torque TAB in accordance with the gear ratios (i2 / i1) that change from second gear to first gear.

Thrust downshifts, ie downshifts in overrun mode, are analogous to the pull upshifts described above. The torques take on negative values and the drive motor 12 must be accelerated.

Fig. 4 shows the torques and speed profiles during the downshift downshift. In the first time interval from t1 to t2, the speed controller, which is part of the control and regulating device 50, is activated. The overlap then takes place in the second time interval from t2 to t3, in which both clutches K1 and K2 are in the sliding state and thereby transmit torque. Here, the differential speed is further adjusted with the help of the first clutch K1, which serves as an actuator for the speed controller. In the third time interval from t3 to t4, the engine torque ωAM of the drive motor 12 is increased in order to rev up the drive motor 12 . At the fourth time t4, the first clutch K1 changes from the sliding state to the holding state. The switching operation is now complete.

In Fig. 4 again ωAM mean the angular velocity of the drive motor 12 ; TV the internal combustion engine torque of the drive motor 12 ; TK1 the torque of the first clutch K1; and TK2 the torque of the second clutch K2.

Fig. 4 shows that the slip of the second clutch K2 between the first and the second time t1 or t2, the thrust of the vehicle on the drive motor 12 decreases and thereby its angular velocity ωAM drops somewhat to a setpoint, which by the third time t3 Control of the closing pressure of the second clutch K2 is used, the closing pressure continuously decreasing, while in the same period the closing pressure of the first clutch K1 becomes increasingly higher until it takes over the full torque in the third time t3 and then the second clutch K2 completely without torque at this time is opened. In the third time interval between the third point in time t3 and the fourth point in time t4, the first clutch K1, which now transmits the full torque, is still in the sliding state, so that the angular velocity ωAM of the drive motor increases in accordance with the new transmission ratio (i2 / i1) in this period can be caused by the thrust of the vehicle. The engine torque TV can be reduced in the time interval from the third to the fourth time t3 to t4 relative to the adjacent time periods.

FIG. 5 shows the transmission output torque TAB on the transmission output shaft 20 over the same period from the first point in time t1 to the fourth point in time t4 during the overrun downshift.

The invention is described below with reference to FIGS . 6 and 7 for a train downshift, ie for a downshift from a higher gear to a lower gear with uninterrupted train operation. A train downshift from second gear to first gear is described here as an example. The train downshift can also take place in three steps, whereby the individual steps can also overlap here. In Figs. 6 and 7 ωAM again represent the angular speed of the drive motor 12; TV the internal combustion engine torque of the drive motor 12 ; TK1 the torque of the first clutch K1; TK2 the torque of the second clutch K2; and TAB the transmission output torque on the output shaft 20 . The four times t1, t2, t3 and t4 coincide in time in the individual figure. The train downshift begins at time t1. The closing pressure of the second clutch K2 is reduced so far that it reaches its slip limit. Through automatic intervention in the control electronics of the control device 50 , the drive motor 12 is accelerated in a speed-controlled manner in accordance with an a priori predetermined speed curve, as is shown in FIG. 6 between the first two times t1 and t2. As a result, the second clutch K2 changes from the holding state to the sliding state. During this first step between the times t1 and t2, the engine torque TV is kept constant at a predetermined target value according to FIG. 6.

At the second point in time t2, the drive motor 12 reaches an angular speed ωAM which is somewhat above the synchronous speed of the target gear. In the example of the first gear described here, "1st", e.g. B. 1 U / s above the synchronous speed. This synchronous speed ωAM is kept constant at a predetermined target value with the aid of a slip control of the control device 50 . For this purpose, the actuator AK2 of the second clutch K2 serves as an actuator for the slip controller. Now the first clutch K1 is closed in a controlled manner from the second point in time t2. While the first clutch K1 is continuously closed in this second step between the second point in time t2 and the third point in time t3, the slip controller automatically opens the second clutch K2 in a controlled manner such that the angular velocity ωAM of the drive motor 12 remains constant. The internal combustion engine torque TV is preferably also kept constant in this second step. This clutch overlap of the two clutches K1 and K2 lasts from the second point in time t2 to the third point in time t3. At the third time t3, the second clutch K2 is then completely open. The first clutch K1 is now completely closed, the differential speed (slip frequency), which, as mentioned above, z. B. 1 U / s, is reduced to zero in the first clutch K1, and this first clutch K1 changes from the friction state to the holding state. This operation is performed according to Fig. 6 in a fourth step, between the third time point t3 and the fourth time t4. Fig. 7 shows corresponding to the pulling downshift of Fig. 6, the output torque TAB on the output shaft 20 of the twin clutch transmission.

In the foreground of all control strategies of the invention is a switching that is as jerk-free as possible. With a thrust upshift, ie an upshift in overrun, the engine has in the source gear, for. B. in first gear, a higher speed than after the shift in the target gear, z. B. the second gear. Here, the engine speed cannot be reduced further by engine intervention, ie by reducing its fuel supply, but only by intervention in the clutch control of the two clutches K1 and K2. Such a situation is assumed for the thrust upshift shown in FIGS . 8 and 9. In the example shown, the source gear, for example, the first gear "1." and the finish gear the second gear "2nd" his. In the first time interval from the first point in time t1 to the second point in time t2, the drive motor 12 must be decelerated when the thrust is upshifted. Since in the example shown the torque of the drive motor 12 cannot be reduced any further (the drive motor is just giving off its drag torque), the pressure (closing pressure) of the clutch of the source gear, in the present example of the first clutch K1, must be reduced so that this clutch slides and the deceleration torque of the drive motor 12 is reduced. As a result, the drive motor is delayed until it reaches an angular velocity ωAM at the end of the first time interval, ie at the end of the first step at the second point in time t2, which is slightly below the angular velocity of the target gear, e.g. B. the second course. The angular velocity of the target gear corresponds to the angular velocity or rotational speed ωAM of the drive motor 12 shown in the fourth time t4. The slip controller of the control device 50 regulates the speed difference in the clutch K1 of the source gear, in this example the first gear in the first interval t1 to t2 for the speed reduction of the drive motor, and in the second time interval t2 to t3, in which the overlap of the two clutches K1 and K2 takes place. Fig. 8, the reduced in the first time interval t1 to t2 and controlled to a constant value in the second time interval decreasing torque shows TK1 of the clutch K1 of the source junction. In the second time interval t2 to t3, the simultaneously controlled increasing torque TK2 of clutch K2 of the target gear is added. At the third time t3, the clutch K2 of the target gear has taken over the full torque and the clutch K1 of the source gear is torque-free and is opened completely. In the third time interval t3 to t4, the angular speed ωAM of the drive motor is increased to the synchronous speed of the target gear by sliding operation of the clutch K2 of the target gear by transitioning this clutch from the sliding state to the holding state.

Fig. 9 shows corresponding to the method of FIG. 8, the transmission output torque on the output shaft 20 TAB. The internal combustion engine torque TV of the drive motor 12 is kept constant during the upshift described in accordance with FIG. 8.

Claims (10)

1.Procedure for shifting a double clutch transmission with two countershafts (V1, V2) and with an output shaft, which can be connected to one another by shifting elements via gear wheels, which form gear stages, each countershaft being assigned a friction clutch (K1, K2), by means of which it is associated with a drive shaft of a vehicle drive motor can be connected, in the initial state before a gear change, the clutch of the countershaft of the source gear - hereinafter referred to as the clutch of the source gear - in the locked state for slip-free transmission of engine torque and the clutch of the countershaft of the target gear - hereinafter referred to as the clutch of the target gear - is completely open so that this countershaft of the target gear is brought to synchronous speed with the switching element of the respective target gear and then the target gear can be engaged by engaging this switching element, after this inserting the target gear to complete a gear change els the clutch of the source gear is opened in a controlled manner by a slip controller so that it changes from the state of sticking to the sliding state and a differential speed is set in it as a function of a target speed of the drive shaft, and thus the clutch of the target gear is closed overlapping in a controlled manner, so that it goes from the completely open state to the sliding state and takes on more and more torques until the clutch of the source gear no longer transmits torque, characterized in that, for upshifts in train mode and / or for downshifts in overrun mode, from the time from which the Coupling the source gear no longer transmits torque and the clutch of the target gear is still in the sliding state, the internal combustion engine torque of the drive motor is adjusted by a speed controller by intervention in a control electronics of the drive motor so that the speed of the drive motor in a vorbe agreed timing of the changed gear ratio is adjusted and that at the end of this adjustment, the clutch of the sliding state changes to the state of detention. 2. Procedure for switching a double clutch transmission with two countershafts (V1, V2) and with an output shaft, which by switching elements via gears together connectable, which gear levels form, each Layshaft is assigned a friction clutch by which they use with a drive shaft of a vehicle Drive motor is connectable, being in the initial state a gear change the clutch of the countershaft Spring duct - hereinafter called coupling of the spring duct - in detention is for slip-free transmission of Engine torque and the clutch of the countershaft Target gear - hereinafter referred to as coupling of the target gear - is fully open so that this countershaft of Target gear to synchronous speed with the switching element of a finish and then the finish Engagement of this switching element can be inserted, after completing the target course for completion the clutch of the target gear opened and a gear change the coupling of the source passage is timed with it is closed overlapping, so that none Traction interruption occurs, characterized, that, to complete a gear change after inserting the target gear for downshifts in train operation and / or  for upshifts in overrun, the closing pressure of the Coupling of the source gear reduced to the slip limit is that then by intervention in the control electronics of the Drive engine whose internal combustion engine torque so is regulated increased that the clutch of the source gear in the sliding state goes and the speed of the drive motor speed-controlled up to a speed setpoint that is close to the synchronous speed of the target gear is that this increased engine speed Slip control of the clutch of the source gear on the Speed setpoint is maintained and temporally related to it controlled overlapping the clutch of the target gear is closed, so that in the sliding state of both Clutches the torque of the clutch of the source gear from the clutch of the target gear is taken over until the Coupling of the target gear is in detention, and that with the Reaching this state of detention or shortly thereafter Clutch of the source passage is opened completely. 3. The method according to claim 2, characterized, that the increased engine torque after Reaching the speed setpoint at the beginning of the sliding overlap of the two Couplings is reduced to a lower value. 4. The method according to any one of the preceding claims, characterized, that when shifting up in overrun Operating situations in which the before a gear change Drive motor already has its lowest possible thrust torque has reached the pressure of the clutch of the source passage is reduced so far that the speed of the drive motor is delayed by sliding this clutch until at or slightly below the synchronous speed of the target gear lies before then due to the overlapping Activation of the two clutches (K1, K2) the torque  without interruption of traction from the coupling of the source gear is shifted to the clutch of the target gear. 5. The method according to any one of the preceding claims characterized, that when switching back in train mode Operating situations in which the before a gear change Drive motor already its greatest adjustable torque gives the pressure of the clutch of the source passage so far is reduced by the speed of the drive motor Slide this clutch up to or up to a little above the Synchronous speed of the target gear is raised before then through the overlapping activation of the both clutches (K1, K2) the torque without Traction power interruption from the clutch of the source gear the clutch of the target gear is shifted. 6.Double clutch gearbox with two countershafts (V1, V2) and with an output shaft, which is switched by switching elements Gears are interconnectable, which gear stages form, each countershaft a friction clutch (K1, K2) is assigned, by which they with a Drive shaft of a vehicle drive motor is connectable, the clutch in the initial state before a gear change the countershaft of the source gear - hereinafter clutch called the source passage - in the state of detention is to slip-free transmission of engine torque and the Coupling the countershaft of the target gear - below Clutch of the target gear called - is fully open, so that this countershaft of the target gear to synchronous Speed with the switching element of the respective target gear brought and then the finish gear by indenting this Switching element can be inserted, after this Engaging the target gear to complete a gear change the coupling of the source passage by a slip controller regulated is opened so that it from the state of detention in the Sliding condition goes and there is a differential speed in it  Dependence on a target speed of the drive shaft sets, and thus overlaps the Clutch of the target gear is closed controlled so that it goes from the completely open state to the sliding state and takes on more and more torques until the clutch no longer transmits torque from the source duct, characterized, that, for upshifts in train operation and / or for Downshifts in overrun, from the time which the clutch of the source gear no more torque transmits and the clutch of the target gear continues in Sliding state is the engine torque of the Drive motor from a speed controller by engaging in control electronics of the drive motor are set in this way is that the speed of the drive motor in one predetermined time course of the changed Gear ratio is adjusted and that at the end of this Adaptation of the clutch from the sliding state in the Detention status passes. 7.Double clutch gearbox with two countershafts (V1, V2) and with an output shaft, which is switched by switching elements Gears are interconnectable, which gear stages form, each countershaft a friction clutch is assigned by which it is connected to a drive shaft a vehicle drive motor is connectable, wherein in Initial state before changing gear the clutch of the Countershaft of the source gear - subsequently coupling the Called swelling duct - in the state of detention is to slip-free Transmission of engine torque and the clutch of the Counter shaft of the target gear - subsequently coupling the Called finish - is fully open, so this Countershaft of the target gear to synchronous speed with brought the switching element of a target gear and then the Target gear engaged by engaging this shifting element can be, after inserting the target gear to Completion of a gear change the coupling of the target gear  opened and the coupling of the source passage is timed so that there is an overlap so that none Traction interruption occurs, characterized, that, to complete a gear change after inserting the target gear for downshifts in train operation and / or for upshifts in overrun, the closing pressure of the Coupling of the source gear reduced to the slip limit is that then by intervention in the control electronics of the Drive engine whose internal combustion engine torque is regulated so far increased that the clutch of the Source gear goes into the sliding state and the speed of the Drive motor speed controlled up to a speed Setpoint is increased, which is close to the synchronous speed the target gear is that this increased engine speed by slip control of the clutch of the source gear on the Speed setpoint is maintained and temporally related to it controlled overlapping the clutch of the target gear is closed, so that in the sliding state of both Clutches the torque of the clutch of the source gear from the clutch of the target gear is taken over until the Coupling of the target gear is in detention, and that with the Reaching this state of detention or shortly thereafter Clutch of the source passage is opened completely. 8. Double clutch transmission according to claim 7, characterized, that the increased engine torque after Reaching the speed setpoint at the beginning of the sliding overlap of the two Couplings is reduced to a lower value. 9. Double clutch transmission according to one of claims 6 to 8, characterized, that when shifting up in overrun Operating situations in which the before a gear change Drive motor already has its lowest possible thrust torque  has reached the pressure of the clutch of the source passage is reduced so far that the speed of the drive motor is delayed by sliding this clutch until at or slightly below the synchronous speed of the target gear lies before then due to the overlapping Activation of the two clutches (K1, K2) the torque without interruption of traction from the coupling of the source gear is shifted to the clutch of the target gear. 10. Double clutch transmission according to one of claims 6 to 9, characterized, that when switching back in train mode Operating situations in which the before a gear change Drive motor already its greatest adjustable torque gives the pressure of the clutch of the source passage so far is reduced by the speed of the drive motor Slide this clutch up to or up to a little above the Synchronous speed of the target gear is raised before then through the overlapping activation of the both clutches (K1, K2) the torque without Traction power interruption from the clutch of the source gear the clutch of the target gear is shifted.