FR2813564A1 - Gearbox for motor vehicle has pair of actuators to control reduction stages of gearbox has pair of actuators to control engagement of different gear ratios - Google Patents

Abstract

The motor vehicle transmission has an engine (2) with a transmission assembly (4) having a first actuator and a gearbox (6) having a second actuator. The gearbox has multiple gears sets each with a gear fixed to a shaft and a second sliding gear. The actuators control the gear engagements and have a control circuit for disengagement of the previous gears, selection of the new ratio and engagement of the new ratio gears.

Description

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The invention relates to a motor vehicle, whose driving chain comprises in particular a clutch, which can be engaged and disengaged in an automated manner, and a gearbox, in which the reduction stages can be changed in a manner automated.

Due to the high degree of automation, such motor vehicles are very complex, resulting in a corresponding high expense when taking into account for example safety and comfort. hitherto, a great variety of efforts have been made to meet these requirements, but there is still a need for improvements, particularly with regard to safety and comfort.

The problem underlying the present invention is to develop a motor vehicle indicated above so that the safety regarding use, operation and / or troubleshooting is improved, the comfort of driving and control is increased and / or that emissions of harmful substances are reduced.

One aspect of this problem is solved according to the invention with the aid of a motor vehicle comprising a drive motor, a torque transmission device comprising a first actuating device, a gearbox comprising a drive shaft. input and an output shaft and a second actuating device, characterized in that the gearbox comprises a multiplicity of groups of gears forming reduction stages and which are respectively formed by a gear pinion rigidly connected to a shaft and by a pinion gear that can be connected to a shaft, a control device is provided and that the first and second actuators can be controlled automatically in a manner controlled by the controller.

The controller for controlling the first and second actuators may also be in the form of two separate control units or control units having separate parts, the control units or the parts of the control units. being then linked together for data exchange.

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 An aspect of the problem in the motor vehicle of the type indicated above can be solved in a vehicle of the type indicated above comprising a drive motor, a torque transmission device, and a clutch comprising a first device actuating, to effect the engagement and disengagement of the clutch, a gearbox such as a gearbox comprising a multiplicity of gear stages and having a second actuating device and which comprises a multiplicity of reduction stages, and a controller, and wherein the first and second actuators can be automatically controlled in a triggered manner by the controller until two reduction stages can be actuated by means of the same switching element, as for the execution of a change of gear ratio a displacement for switching and possibly an actuating element selection displacement are required, and a change in the gear ratio includes the steps including - clearing the old gear ratio, - possibly selecting a new gear element. switching, - the commitment of the new gear stage, characterized in that a disengagement of an old gear ratio and a commitment of a new gear stage that can be actuated by means of the same switching element, are executed at less without a significant component of selection movement.

In a particularly advantageous embodiment, it is provided that the disengagement of an old gear stage and the engagement of a switching element of a new gear stage that can be actuated by means of the same switching element are executed. without the actuating element in the meantime passing through the neutral position. The actuating element thus remains engaged with the switching element during the entire switching process.

The complementary shape connection / force connection between the actuating element and the switching element is established by

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 example directly or with the interposition of a transmission element such as a switching fork so that under the expression "switching element", it should be understood that it is also a group of functions to from a sliding sleeve and a switching fork - possibly also other transmission elements.

According to another aspect of the invention, it is provided in a motor vehicle comprising a torque transmission device comprising a first actuating device, a gearbox comprising a second actuating device, which has a multiplicity of stages of operation. gear, and a controller, and wherein the first and second actuators can be controlled automatically in a triggered manner by the controller and gear stage changes are made in accordance with curves characteristics stored in a memory associated with the control device, that during an operating mode switching phase of the drive motor, the first actuating device and / or the second actuating device is not controlled, so during the switching phase, no change of gear stage is executed and / or the clutch is not operated.

In a particularly advantageous exemplary embodiment, for this purpose a part of the control device, which is associated with the drive motor, can be arranged for example for controlling the ignition, the valves, the injection, the setting of the throttle valve or value 1, this part of the control device being able to be arranged in the form of an autonomous control device and being connected, for data exchange, to a part of the control device, which is associated to the gearbox, and to that part of the control device associated with the gearbox is transmitted the information concerning the applied switching of the operating mode of the drive motor, in which case the information is transmitted at intervals between the parts of the control device, and the information concerning the applied switching of the operating mode.

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 The drive motor is transmitted for at least one transmission interval before switching is initiated.

Advantageously, the information relating to the applied switching of the operating module of the drive motor is transmitted, in the exemplary embodiment, for 1 ms to 1 s and in particular for 10 to 50 ms before switching on, this duration may also vary depending on the transmission interval, in another embodiment.

Another aspect of the problem of the invention is solved in a motor vehicle comprising a driving motor, a torque transmission device comprising a first actuating device, a gearbox comprising a second actuating device, which has a multiplicity of gear stages, and a controller, and wherein the first and second actuators can be controlled in an automated manner in a triggered manner by the control device and changes in gear stage are made according to characteristic curves, and wherein at least a first set of characteristic curves, which comprises at least one characteristic curve, is fixedly stored in a memory associated with the controller and at least a second set of curves characteristics, comprising at least one characteristic curve, is adapted, of a adaptively, on the basis of a short delay or a significant delay, characterized in that the driver has the possibility to choose between the use of the first set or the second set of characteristic curves.

In a preferred embodiment of the invention, it is particularly advantageous for at least one characteristic curve of the second set to be transferred into the first set. An adaptively adapted set of characteristic curves may be transferred into the memory and this set of characteristic curves may again be called up, modified, over-recorded on this set or erased.

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 Advantageously, the at least one characteristic curve can be erased only when it is not active, that is to say when precisely no control is performed according to this characteristic curve. It may be appropriate to erase a characteristic curve in the case where no control is performed according to this characteristic curve for a long period of time or in the case where the memory space is necessary for the storage of another characteristic curve.

It is furthermore advantageous that in place of the at least one characteristic curve, after erasure of the latter, another characteristic curve stored in the memory appears, so that permanently necessary characteristic curves are available for the command.

Another aspect of this problem is solved in a motor vehicle comprising a driving motor, a torque transmission device comprising a first actuating device, a gearbox comprising a second actuating device, which comprises a multiplicity of reduction stages, and a control device, and in which the first and second actuation devices can be controlled in an automated manner, in a manner triggered by the control device, in accordance with characteristic curves, in a manner corresponding at least to a displacement program, characterized in that during a predetermination for the selection of a gear stage is attempted to engage this gear stage and in the case of non-availability, it engages a stage of demultiplication replacement gear ratio. A gear stage may not be available, for example due to a mechanical fault of the switching engagement clutch of the switching finger, the switching fork or other element involved in a change of gear stage. for example also because of a defect in the detection system, which allows the identification of the position of such elements, or the control device.

Advantageously, as a replacement, the next higher reduction stage is engaged in the case where the stage of multiplication

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 currently engaged and the maximum gear reduction stage, and in the preferred embodiment, as a replacement, the next lower gear stage is engaged and in the case where the gear stage currently engaged is a reverse gear as a replacement the neutral is engaged.

According to a preferred embodiment of the invention, the gear stage engaged as a replacement remains engaged until, in accordance with the traveling program, a gear stage other than an unavailable gear stage must to be engaged.

Suitably, in the case of a new predetermination for the selection of a gear stage not previously available, it is desirable again to engage this gear stage to the extent that the replacement stage has already been exited. . In this context it is wise to no longer undertake any attempt to commit a report after a determined number of unsuccessful engagement attempts for the multiplier stage considered.

Another aspect of the problem is solved in a motor vehicle comprising a drive motor, a transmission device comprising a first actuating device, a gearbox comprising a second actuating device, which comprises a plurality of stages of operation. gear, and a controller, and wherein the first and second actuators can be controlled in an automated manner, in a manner triggered by the controller, and the controller can act to control the motor of the drive, characterized in that during a gear change, a determined motor torque and / or a determined torque gradient are required by the control device.

In a preferred embodiment of the invention, the required torque is set to a value which is greater than the minimum torque (creep torque) of the drive motor. It may be a pair equal to zero, but also a pair which is not zero, but which is greater than the creep torque.

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 Advantageously, the required motor torque is adjusted as a function of at least one parameter, and in the preferred exemplary embodiment, a parameter of displacement program, a position of the load lever, a setpoint ratio, a ratio real, a type of driver and / or a degree of sportiness.

It is particularly appropriate for the adjusted torque to decrease as the position of the load lever increases and / or the gradient of the torque decreases in absolute value, which causes the torque to decrease less strongly during the change of the gear stage. .

In the case of a sports driver or in the case of judicious adaptation, advantageously the engine torque set is comparatively high and / or the torque gradient is comparatively low in absolute value, and here also a less abrupt decrease in torque is obtained during the change of the gear stage.

Furthermore according to another aspect of the invention there is provided a motor vehicle comprising a drive motor, a torque transmission device comprising a first actuating device, a gearbox comprising a second actuating device, which has a multiplicity of gear ratios, a control device and wheels which are associated with rotational speed sensors, and in which a wheel slip is identifiable and the first and second actuators can be controlled in an automated manner in a manner triggered by the control device, characterized in that even in the case of wheel slip, changes in the gear ratio are performed in accordance with the actual vehicle speed. In particular a wheel of the vehicle, which skates, also does not lead to an early change of gear stage.

In a particularly preferred embodiment of the invention, it is very advantageous that the speed of the vehicle is determined in a standard way, that is to say when the wheels do not slip, from the signal of the speed sensor. of wheel rotation, which signals the maximum speed, while in a state in which the wheels spin, the speed of the vehicle

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 is determined from the last valid speed of the vehicle or from the signal of a sensor of the speed of rotation of a wheel which is not driving, so that the determined speed of the vehicle then also corresponds to the speed effective.

The problem underlying the invention is furthermore solved by the fact that in a motor vehicle, the gearbox of which comprises in particular a reverse stage, an engagement of a reverse stage only takes place when the difference between the rotational speeds of the input shaft and the output shaft is at least approximately zero.

For this purpose it is appropriate to wait for a certain time of operation of the input shaft of the gearbox, before the engagement of a reverse stage and according to at least one parameter, and the parameter is an initial difference between the rotational speeds of the input shaft and the output shaft and / or a temperature of the gearbox.

In a preferred embodiment of the invention, in the case of a temperature of the gearbox between 40 C and 200 C and in particular between 80 C and 120 C for each difference of 1000 min-1 between the speeds of rotation, waiting for the flow of a time of inertia less than 10 s and in particular between 0.5 s and 2 s. In another embodiment, in which the influence of said factors is different or in which other factors influence the start-up time, it is appropriate to choose the starting time according to the then prevailing parameters so that the difference between the speeds of rotation is also reached from a value at least approximately zero, and with sufficient security.

Another aspect of the problem is solved in a motor vehicle comprising a drive motor, a torque transmission device comprising a first actuating device, a gearbox comprising a second actuating device, and having a multiplicity of reduction stages, and a control device, the control of the second actuating device being carried out in an automated manner, by being triggered by the control device, in a

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 automatic operating state or, in a type of manual operation, by means of a driver action at the control device, characterized in that, if necessary, a change is made automatically to pass through the automatic mode of operation.

Suitably, the automatic mode of operation, on which automatic switching is performed, is a type of emergency operation, in which the switching frequency is reduced and / or the number of available reduction stages is limited.

A change in the type of automated operation is advantageously effected, in a preferred embodiment of the invention, during the failure or the presence of a defect in one or more components.

The aforementioned solutions of different aspects of the problem underlying the invention and various embodiments provide the desired success, especially according to the combination present, but also each for them.

According to another idea underlying the invention it is proposed, particularly in connection with the gearbox of the vehicle, to provide an electric motor, whose rotor can be connected for example to a mass of inertia that can rotate freely , which most of the time can be advantageously isolated using at least one clutch vis-à-vis a drive unit, such as an internal combustion engine, and vis-à-vis a driven unit, such as a driven shaft, for the use of the inertia mass, or form this mass of inertia so that with these devices, it is possible to have hybrid drives.

According to one embodiment of this idea of the invention, the gearbox allows a global use of the electric motor for example as a starting unit by the internal combustion engine, current generator, partial drive device , complete drive unit and unit for converting kinetic energy into electrical energy, or kinetic rotation energy by using the rotor as a mass of inertia in the case of

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 deceleration of the vehicle while the internal combustion engine is already coupled (recovery).

Other features and advantages of the present invention will emerge from the description given hereinafter taken with reference to the accompanying drawings, in which - Figure 1 shows schematically and by way of example a vehicle having a torque transmission device actuated d an automated manner and a gearbox that can be operated automatically; FIG. 2 represents a flowchart for the reduction of the switching duration; Figure 3 shows a flowchart for preventing switching during a change of operating mode of the drive motor; FIG. 4 is a diagram for storing appropriate switching characteristic curves; FIG. 5 represents a diagram for the selection of a replacement report, in the case where the setpoint report can not be engaged; - Figure 6a shows a diagram for controlling the drive motor during phases of interruption of the traction force; FIG. 6b shows characteristic curves of setting torques of a field of characteristic curves for different positions of the load lever as a function of the reference ratio; Figure 7 shows a flowchart for preventing the passage at a higher speed when wheels are spinning; and Figure 8 shows a schematic of a strategy for engaging reverse with deceleration in inertia operation.

FIG. 1 schematically represents, by way of example, a vehicle 1 comprising a torque transmission device 4 and a gearbox 6. The torque transmission device 4 is disposed of

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 in the flow of force between a drive motor 2 and a gearbox 6; suitable between the drive motor 2 and the torque transmission device 4 is a divided mass of inertia, the partial masses of which can rotate relative to one another by means of the interposed mounting of a device spring damper, which has the effect that in particular the technical characteristics of oscillations of the drive chain are improved. Preferably the device is combined with a damping device for absorbing and compensating for jolts of rotation or a device for compensating for jolts of rotation and a device for reducing jolts of rotation or a device for damping vibrations, as described in particular in the publications DE OS 34 18 671, DE OS 34 11 092, DE OS 34 11 239, DE OS 36 30 398, DE OS 36 28 774 and DE OS 37 21 712 of the applicant . The vehicle 1 is driven by a drive motor 2, which is here represented in the form of a combustion engine such as a gasoline engine or a diesel engine; in another embodiment, the drive device can also be realized by means of a hybrid drive device, namely by electric motor or by hydraulic motor. In the exemplary embodiment shown, the torque transmission device 4 is a friction clutch, by means of which the drive motor 2 can be separated from the gearbox 6 in particular for starting or for executing processes. of commutation. A higher or lower torque is transmitted by means of an increasing engagement or disengagement of the clutch, and for this purpose a clamping plate and a pressure plate are displaced axially relative to each other. and more or less drive an intercalated friction disc. The torque transmission device 4 arranged in the form of a clutch is advantageously of the type with automatic adjustment of clearance or wear compensation, that is to say that the wear of the friction linings is compensated so that a weak and constant disengaging force is guaranteed. Preferably, the invention is combined with a friction clutch of the type described in particular in the applications DE OS 42 39 291, DE OS 42 39 289 and DE OS 43 06 505 of the applicant. The wheels 12 of the vehicle 1 are driven by means

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 a shaft 8 via a differential 10. The drive wheels 12 are associated with speed sensors 60, 61 and possibly also only a rotation sensor 60, 61 is provided, such sensors delivering respectively a signal corresponding to the speed of rotation of the wheels 12; in addition or alternatively, a sensor 52 is provided at another appropriate location in the drive train, for example on the shaft 8, to determine the output rotational speed of the gearbox. The transmission rotation speed of the gearbox can be determined using another sensor or, as in the previous embodiment, be determined from the speed of rotation of the drive motor. , and for example one can determine the gear ratio set in the gearbox. An actuation of the friction clutch 4, which is advantageously compressed, but in another embodiment may also be advantageously placed in tension, is carried out in the present case by means of an actuating device. 46, such as an actuator of the clutch. For the actuation of the gearbox 6, there is provided an actuating device which comprises two actuators 48 and 50, one of the actuators executing a selection actuation and the other a switching actuation. The coupling actuator 46 and / or the actuators 48, 50 of the gearbox are arranged in the form of DC electric motors, and in another embodiment, in particular when intense driving forces are required. it can also be very advantageous to provide a hydraulic system for actuation. The control of the clutch 4 and the gearbox 6 is effected by means of a control device 44, which suitably forms with the actuator 46 of the clutch, a construction unit and, in another embodiment, it may also be advantageous to install this unit at another location in the vehicle. The clutch 4 and the gearbox 6 can be actuated automatically in a type of automatic operation by means of the control device 44, or in a manual mode of operation by means of a driver input of a gear selector control device 60, such as the gear change lever

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 speed, the input being detected by means of a sensor 61. In the type of automatic operation, changes in reduction stages are performed by means of a corresponding command of the actuators 46, 48 and 50 in accordance with characteristic curves, which are stored in a memory associated with the control device 14. There is provided a multiplicity of displacement programs fixed by at least one characteristic curve and between which the driver can make a selection, such as for example a sports driving program. wherein the drive motor 2 operates in a power-optimized manner, an economy driving program, in which the drive motor 2 operates in an optimized manner according to the consumption, or a winter program, in which the motor vehicle 1 operates in an optimized manner on the basis of the safety of movement; in addition, in the embodiment described, characteristic curves can be adaptively adapted to, for example, the behavior of the conductor and / or other marginal conditions such as friction on the roadway, the outside temperature, etc. A control device 18 controls the drive motor 2 by influencing the delivery of the mixture or the composition of the mixture, and in the figure as representative element there is shown a throttle valve 22, whose opening angle is detected by means of an angle sensor 20 and whose signal is supplied to the control device 18. In other embodiments of the control of the drive motor, the control device 18 has, in the where it is a combustion engine, a corresponding signal, on the basis of which the combustion of the mixture and / or the volume sent can be determined. Advantageously, the signal of a lambda probe present is also used. Furthermore, in the present embodiment, the control device 18 receives a signal from a load lever 14 actuated by the driver whose position is detected by means of a sensor 16, a signal concerning a speed of rotation. of the motor, which is produced by a rotational speed sensor 28 which is associated with the driven shaft of the motor, a signal of a sensor 26 of the position in the suction pipe and a signal from a sensor 24 of the

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 temperature of the cooling water. The control devices 18 and 44 may be arranged in parts that are structurally and / or functionally separate and are advantageously interconnected, for example by means of a CAN bus 54 or using another electrical link for reciprocal data exchange. However, it may also be advantageous to combine the parts of the control device, in particular because a combination of functions is no longer possible clearly and cooperation is necessary. In particular during certain phases of the change of the reduction stages, the control device 44 can control the rotational speed and / or the torque of the drive motor 2. Both the actuator 46 of the clutch and the The actuators 48 and 50 of the gearbox produce signals from which at least one position of the actuator can be obtained, which is sent to the control device 44. In this case, the position is determined inside the actuator, and for this purpose uses an incremental generator which determines the position of the actuator with respect to a reference point. In another embodiment, it may however also be appropriate to arrange the generator outside the actuator and / or to provide an absolute determination of the position for example using a potentiometer. A determination of the position of the actuator is therefore very important with regard to the actuator of the clutch since, as a result, the point of attack of the clutch 4 can be associated with a determined travel of engagement and therefore at a position of the actuator. Advantageously, the driving point of the clutch 4 during commissioning and during operation is determined again and again, in particular according to parameters such as clutch wear, clutch temperature. etc. A determination of the positions of the gearbox is important in connection with the determination of the engaged gear ratio. In addition, the control device 44 receives signals from the sensors 62 and 63 of the rotational speeds of the non-driving wheels 65 and 66. For the determination of a vehicle speed, it may be wise to use the average value sensors 62, 63 and 60, 61 rotational speeds

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 to compensate for differences between rotational speeds, for example in the case of crossing a curve. Using the rotational speed signals, the speed of the vehicle can be determined and furthermore also an identification of slip or slip can be made. In the figure, output links of the control device are shown in the form of solid lines. The input links are represented by dashed lines. The connection of the sensors 61, 62 and 63 with the control device is simply indicated.

Figure 2 shows schematically and by way of example a flowchart 200 for reducing the switching time. In automated gearboxes, a gearshift or switching operation between two speeds or gear is performed such that, in the case of a gearshift, an old gear ratio A is disengaged, thereby that the switching actuator disengages the associated sliding sleeve of the switching clutch, that the sleeve approaches the region of the neutral, and that when the sliding sleeve corresponding to the old ratio A is disengaged, the selection actuator executes a corresponding actuation, the switching clutch of the new gear B is selected by means of a movement of the selection actuator and finally the new gear B is engaged by means of the switching actuator in that the associated switching clutch is switched on. In the case where the ratio A and the ratio B are situated in the same switching channel, that is to say they are actuated by the same sliding sleeve, it is not necessary to approach the neutral zone temporarily. or to select a new switching clutch and therefore at least to a large extent, and in a completely advantageous manner, a selection shift can be dispensed with. In the flowchart 200, it has been shown how, in a change 201 between two ratios A and B, it is first determined, at 202, whether the two ratios A and B are associated with the same switching clutch. If this is not the case, in 209, after disengagement of the old report A, in 203, the selection drive to approach the neutral area (of the selection switch channel is actuated, 204 then

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 the new switching channel (the new switching clutch) is selected, at 205, and then the setpoint ratio B is engaged, at 206. In the case where the ratios A and B are associated with the same switching clutch, at 210 after the old report A 207 has been deactivated, there is a direct engagement of the new ratio B at 208, so that the switching time is reduced according to the intermediate selection movement, which is then not executed.

With reference to FIG. 3, there is shown diagrammatically and by way of example a flowchart 300 for preventing switching in the case of a change of operating mode of the drive motor 2. The drive motors, in particular internal combustion engines, may comprise a plurality of operating modes; for example, a direct injection gasoline engine has, apart from an operating mode, in which it operates with X = 1, at least one other mode of operation, such as a cold start mode for a transmission with improved cooling, a mode in which it operates to increase the power with a larger mixture for X <1, or a mode, in which is executed an operation with 1> 1. The junction between different modes of operation of the engine must s' in a comfortable and optimal manner concerning the emission reduction of harmful substances, and to this end it is advantageous that, during such a transition, no additional access to the engine is necessary because of variable conditions in the environment. level of the clutch 4 or the gearbox 6 and that it appears and a disturbance of the operating mode at a later time and for only a brief interval of te mps, and the clutch must therefore remain closed and no gear change must be performed. For this purpose the control unit 44 of the gearbox and the clutch must receive timely information about a change in the operating mode of the engine 2. In the present embodiment, the communication between 18 and the control unit 44 of the gearbox and the clutch is carried out in a clockwise manner so that here it is very advantageous that a piece of information

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 concerning a change in operation of the engine 2 is transmitted at least one transmission rate before the triggering of this mode. A required gear change can then be removed and executed only after a change in the operating mode of the engine 2, with a slight delay; the transmission rate between the engine control unit and the gearbox or clutch control unit 44 is about 30 ms in the present embodiment. The representation in the diagram 300 shows that, as in the case of a current change in the engine operating mode, see block 301, a switch preventing bit is set in step 302. Once the change is made. operating mode executed, see step 303, the switching prevention bit is cleared, step 304. In the case of a switching request, see block 305, the switching prevention bit is controlled by the 44 of the control unit of the gearbox or the clutch, see block 306, and in the case where it is positioned, see branch 307, the commutation is not executed, step 308, and when the bit preventing switching is not set, see step 309, switching is executed, step 310, and the switching process is complete, see block 311. In this case the described switching prevention is time limited , and the limitation in time can move in a zone e between zero and a few seconds. Further, after an executed change of the operating mode, such a switching prevention can be prevented, for a certain time, on the basis of a current change in the operating mode of the drive motor for a certain time, preferably in a time ranging from zero to a few seconds or minutes, so that the transmission or clutch control unit 44 is protected against a switching prevention signal oscillating. In the manual operation mode of the gearbox, during the gear change in which gear changes are executed in a driver-initiated manner, the described switching prevention is advantageously not active; likewise

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 the switching prevention function can be disabled in a type of automatic transmission operation.

Figure 4 shows schematically and by way of example a diagram 300 for storing suitable switching characteristic curves. In the case of automated gearboxes of the type considered, commutations are carried out in accordance with characteristic curves, in accordance with driving programs, which are stored in a memory. Depending on the multiplicity of parameters, such as the rotational speed of the motor, the position of the load lever, the operating mode of the engine or the gearbox, etc., characteristic curves are selected in which the moments Switching and also switching processes (clutch opening, switching, closing the clutch - unwinding in time, torque) are fixed. On the one hand, characteristic curves can be selected automatically in the type of automatic operation by means of the control unit 44, and on the other hand the driver himself has the possibility of determining which characteristic curves must be used. . In the diagram 400 in Figure 4, there is shown schematically by way of example a first set 403 and a second set 404 of such characteristic curves, each set comprising at least one characteristic curve. Furthermore, in the present exemplary embodiment, the driver can select, see block 402, also another adaptable set of characteristic curves, in which the characteristic curves can be adapted for example to the behavior of the conductor. In the present exemplary embodiment, the first and second sets of characteristic curves are stored permanently in a memory associated with the control device 44; the driver is also able to memorize an adaptively adaptable set of characteristic curves as other driving programs in the memory, so that he can refer to them thereafter. Optionally, it may also be very appropriate for several sets of adaptive adaptive curves to be stored in the memory. Advantageously at any time the driver can modify a set

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 adaptively adapted characteristic curves, which is memorized by the driver, or can modify an overexcription recording on this set. However, it is advantageously possible that when it is not active; instead of a stored driving program, another fixed or adapted driving program appears, so that a selection of the deleted program does not lead to invalid switching times and switching processes and therefore dangerous. In addition it can be very advantageous, in an exemplary embodiment, to give priority to characteristic curves, for example as a function of the frequency of their use in the sense that characteristic curves, which are used infrequently or are not used for a certain period of time, receive a low priority with respect to storage and therefore are erased or are intended to be erased or can be easily erased, and characteristic curves, which are used frequently or have been used only a short time ago. time are given a high priority in relation to the storage, that is to say are difficult to erase or are not erasable. In a preferred embodiment, advantageously one can also store several sets of characteristic curves which comprise at least one characteristic curve, perform a surjoin recording on this set and erase this set; here, in particular, the possibility of assigning priorities is advantageous in order to erase the characteristic curve having the lowest priority or to perform an overexcription recording on this curve - when a characteristic curve has to be erased or when a recording has to be made in oversubscription on this curve.

Figure 5 shows schematically by way of example a flowchart 500 for the selection of a replacement report, in the case where the setpoint report can not be engaged. A temporary or permanent defect in the gearbox or in the kinematic section of the selection drive or switching drive or in the switching selection drive itself may lead to the fact that a requested report can not be initiated. This is why in the case of a switching request

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 501, the control unit 44 checks, before executing the switching, whether the setpoint report is available, see block 502. If it is the case, the switching is executed, see block 503. Otherwise - independently of the report which is the set-point report, see blocks 504 and 506 - a replacement report is initiated. If the setpoint ratio is the highest gear, the next lower gear is engaged as a replacement, see block 505, and if the gear is the reverse gear, the switch is performed as a replacement. on the neutral, block 507, while in all other cases, the replacement ratio is the next higher ratio, see block 508, and if therefore for example the 3rd report is not available, the 4th report is engaged as a replacement. Since the defect may be temporary, when a new predetermination of an unavailable report is attempted, an attempt is again made to insert this report. Under these conditions, it is wise to execute no commitment attempts after a determined number of unsuccessful engagement attempts. For example, after one, two, three or four or possibly more attempts to engage a gear stage, other attempts to engage this gear stage can be ruled out. After unsuccessful engagement tests, according to an alternative embodiment, it is also possible to carry out an availability check, regardless of a renewed attempt, advantageously in a repeated manner during given time intervals, so that a demultiplication stage, which has been blocked, may be released again or a counter may be reset for unsuccessful engagement attempts.

Figures 6a and 6b show schematically and by way of example how the drive motor 2 can be controlled during the interruption phase of the pulling force, which occurs during a switch. In the case of automated transmissions, during an interruption in the traction force that occurs during a switching process, the torque of the drive motor is reduced to its minimum speed (creep time). Once the switching is completed, when the clutch 4 is closed again and therefore

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 the flow of force is restored, it is advantageous according to aspects of comfort and power, that depending on the multiplicity of parameter sizes, there is a defined torque (adjustment torque); for example the adjustment torque can be adjusted according to the position of the load lever, the setpoint ratio, the actual ratio or the type of pipe, and the adjustment torque increases when the position of the load lever increases, so to provide a slower decrease in the rotational speed of the motor, and together with the setpoint ratio, a characteristic field can be formed, which forms the basis for the value of the adjustment torque. For different travel programs, such as a fuel economy program, which is optimized from the point of view of consumption, a power-optimized sports driving program or an optimized driving program from the point of view of safety, for uniform pavements, there are provided corresponding fields of characteristic curves for adjusting the adjustment torque; in addition, advantageously a dependence vis-à-vis the type of operation of the gearbox - automatic or manual is provided. Since in a sports driving program, it can be assumed that the driver, who tends to have a sporty driving feels desirable a slower decrease in the engine rotational speed during the switching operation, here for example the adjustment torque becomes lower - the reduction is therefore not so high - as in the case of a economy program. For example, in FIG. 6B, characteristic curves of the adjustment torque of a characteristic field for different positions of the load lever are shown as a function of the setpoint ratio, the adjustment torque indicates the torque whose engine torque is reduced during the interruption phase of the traction force. In the case of a position of the load lever at 0%, which corresponds to the fact that the accelerator pedal is not actuated, the engine torque is therefore reduced by a relatively high value, whereas in the if a position of the load lever to 100%, which corresponds to the complete depression of the accelerator pedal, a very low reduction of the engine torque is achieved. In the characteristic curves it can be further seen that for

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 higher setpoint ratios, there is essentially a lower reduction in torque than in the case of lower setpoint ratios, and in particular a multiplicity of parameters, for example a spacing between the different stages of reduction, are decisive. FIG. 6a schematically represents a flowchart for controlling the drive motor during phases of interruption of the traction force, for example in the case of an automated gearbox with a type of manual or automated operation and a program from walking to the economy or a sports driving program. At the beginning of a switching, see block 601, the intermediate quantity z is set to a certain predetermined value, step 602, whose motor torque is reduced during a period of interruption of the traction force. Then, in step 603, an intermediate storage is performed in x, the current setpoint, and in y, the current position of the load lever. Regardless of whether the sports driving program is activated or not, see block 604, a new z value is read from a feature field for the sports driving program, see block 605, or for the training program. economy-oriented, see block 606, the value of which is reduced the motor torque, the fields of characteristics corresponding to the field of characteristics taken as a basis for the characteristic curves in Figure 6b. In addition, depending on the type of operation of the gearbox, see block 607, in the manual operation mode, if necessary, the value z is increased further, in step 608 - that is to say that the motor torque is more strongly reduced - or in the automatic operation type, the value is taken directly as from the characteristic field and is used for the reduction of the motor torque, see step 609. When shifting to a higher speed for example, the rotational speed of the engine should be greater than the input rotational speed of the gearbox at the end of the switching process, since the motor can therefore be brought particularly rapidly to the speed of rotation. synchronous rotation, under the effect of such a coupling. Outside the control of the adjustment torque, which is shown in the flowchart of Figure 6a, in a variant

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 of the exemplary embodiment, it can also be advantageous for the adjustment torque to be adaptively controlled, in that a difference between the effective rotational speed of the motor and the desired desired speed of the motor is determined and this determined difference is entered in the value of the adjustment torque, which must be adjusted later. In another embodiment, advantageously the motor rotation speed is adjusted during the interruption of the traction force, in that for the control of the motor is predetermined a setting torque, which is fixed by the adjustment difference between the set rotation value and a real engine rotation speed; the set rotational speed is advantageously greater, by a defined value, to the speed of rotation of the gearbox. Suitably, the velocity is linear with proportional and integral behavior or proportional, integral and differential behavior, and in another embodiment, it is preferable to use a nonlinear dependence, such as a two-point control. .

In Figure 7, there is shown schematically by way of example a flow chart 700 for preventing the passage to a higher speed, in the case where wheels slip. It is assumed that a wheel slip is present, this being indicated for example on the basis of a comparison of the rotational speeds of at least one driving wheel and a non-driving wheel or by means of a determination of gradient of the speed of rotation. As indicated, in the exemplary embodiment a determination of the speed of the vehicle is performed in a normal state, see block 701, based on the known maximum signal of the rotational speed, Na rotation speeds of the wheels motor and Nna non-driving wheels being received. This method of determining the speed will hereinafter be referred to as the strategy of the maximum. The rotation speed Na of the drive wheels is detected in the present embodiment by a rotation speed sensor 52 mounted on the output shaft of the gearbox, and in another embodiment of the invention advantageously sensors 60 and 61 of the rotational speed are mounted additionally or alternatively on the wheels 12 themselves since a gearbox output shaft sensor

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 can deliver only an average value for different wheel rotation speeds 12. A correlation of the rotation speeds Na and Nna for a certain time, see block 706, for example in the range of a few milliseconds to a few seconds, in particular between 700 ms and 1.2 s within a certain range of tolerances up to 150 nm-1, and in particular up to 50 nm-1 in accordance with a vehicle speed of about 5 km / h, see block 707, a switching is performed in step 703 to go into a state "clear identification of a slip" - in accordance with a free switching, to deviate from the strategy of the maximum - which is characterized by the fact that from this state it is also possible to deviate from the maximum strategy to determine the speed, and that in the case of the criterion Na> Nna, in a state where the wheels spin, see block 705, a determination of the speed of the vehicle is done then s from the highest speed of rotation of the non-drive wheels 65, 66, taking into account the last determined speed, see block 702. This dependence on the last determined speed of the vehicle is particularly important since a deviation from the strategy of the maximum for determining speed represents a safety risk, which can be countered in this way by the fact that the speed determined must not fall to the point of safety. below the speed determined before, to be identified as valid, and takes into account a certain time interval from the last valid speed signal, which avoids inadmissible downgrades. Thanks to the described determination of the speed of the vehicle from the rotation speed Nna of the non-driving wheels, the transition to a higher speed is prevented due to the fact that the driving wheels - which skate - turn faster, and the passage at higher speeds does not occur due to other parameters, such as the position of the load lever. When the rotational speed of the driving wheels 12 is again equal to or less than the speed of rotation of the non-driving wheels 65, 66 or in the case of the presence of interruption conditions, for example an error of a signal, a resetting of the control unit, a brake actuated or a corresponding time condition, see block 704, the

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 operation returns to the normal state with determination of the speed in accordance with the strategy of the maximum, block 701. Similarly a return to the normal state from the state "net identification of a skating", see block 703 , occurs in the condition Na> Nna, block 707, so that no deviation from the strategy of the maximum is possible directly.

Figure 8 schematically shows by way of example a diagram 800 of a strategy for inserting the commitment of a reverse gear, with a delay of inertia. In particular unsynchronized reverse gearing, it is important that when engaging the gear, there is equality between the rotational speeds of the input shaft of the gearbox and the output shaft. of the gearbox. Since the reverse gear is generally activated when stopped, this requires that the input shaft of the gearbox be at least almost stopped. After opening the starter clutch, it may occur a further rotation of the input shaft of the gearbox, which is braked only by the losses present in the gearbox. This is why the temperature of the gearbox or the difference between the starting rotational speeds of the input shaft and the output shaft of the gearbox has a great influence, a higher temperature of the gearbox and / or a higher initial difference between the rotational speeds of the shafts resulting in a longer duration of inertia operation, which may be important. When a switching request is made for reverse gearing, see block 601 - irrespective of certain parameters, for example the initial difference between the rotational speeds and the temperature Tceu of the gearbox, see blocks 804 and 805 - it is necessary to wait a certain time of inertia walk at, see block 802, before there is at least an approximate identity between the rotational speeds of the input shaft and the shaft of the gearbox, before step 805 reverse gear is engaged. The waiting time is equal, in the exemplary embodiment, for 1000 min-1, to about 1 s for a gearbox temperature of 100 C, the temperature of the gearbox being determined by means of a temperature model, while the last speed of

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 rotation is determined from the friction torque at the clutch or by the vehicle speed for the gear engaged. Since in particular in the case of reverse gear, there may be so-called "blockages", in which a tooth is applied against a tooth and there is no difference between the speeds of rotation. there is only a very small difference between the rotational speeds, if one tries advantageously several times to engage the reverse, in the exemplary embodiment, attempts are made, while in another embodiment, it can be advantage to make more than two attempts, for example to perform three, four, five or six attempts.

Another idea of the invention relates to the selection of stages of reduction in a described vehicle having a gearbox that can be operated automatically, in an emergency situation. In an exemplary embodiment based on this idea of the invention, in the case where a normal operation of displacement can not be maintained, a commutation is executed notably from the operating mode M to switch to an emergency operating mode automatic transmission DNodauf, in which a selection of a reduction stage as also in the automatic operating mode D, is performed in an automated manner by being triggered by the control device, with the difference that in DNodauf, it has only a limited number of gear stages. Advantageously, a limitation to the speeds 1, 2 and to the reverse is executed, which has the effect that, on the one hand, because of the optimized movement speed, an increase in safety is obtained and that on the other hand the The need to go to a workshop is clearly signaled to the driver. Such a situation, in which a normal operation of displacement can not be maintained, can be triggered for example by the failure or the detection of an error of sensors or signals, such as signals of the engine control unit. , signals of the rotational speeds of the wheels or signals of the selection lever, or by an inadmissible thermal load of the system or of various components such as actuators, the electronic control system,

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 the clutch, the clutch system or the gearbox. The temperature is determined using temperature sensors or using a temperature model. In the case where, in the manual operating mode M, the driver overloads the system by means of frequent gearshift requests, in another embodiment, all the gear stages are available in the DNoeauf source operating mode, but the switching frequency is advantageously reduced, and possibly there is also a control of the control members, which differs from the normal operation, so that an overload is avoided.

According to another idea of the invention it is proposed to provide, in connection with the gearbox of the present vehicle, an electric motor, whose rotor comprising for example a mass of inertia which can rotate freely, can be advantageously isolated by the intermediate of at least one clutch, vis-à-vis the input unit as well as the internal combustion engine and the driven shaft for the use of inertia, or form this mass of inertia, so that hydraulic drives are possible with these devices. According to this embodiment, the gearbox allows the consequent use of the electric motor, for example as starter unit for the internal combustion engine, a current generator, a partial drive device complete drive and as a unit for converting kinetic energy into electrical energy or kinetic rotation energy, by using the rotor as a mass of inertia, in the case of deceleration of the vehicle, when the internal combustion engine is decoupled (recovery).

The claims appended to this application are wording proposals, without prejudice to obtaining continuing patent protection. The applicant reserves the right to claim further features or combinations of features which heretofore have only been disclosed in the description and / or drawings.

References used in the subclaims relate to the further development of the object of the main claim through

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 the features of the respective subclaims; they should not be considered as a waiver of self-protection of the purpose of the features or combinations of features of the relevant subclaims.

Since the subject-matter of these claims may constitute, in the light of the technical condition on the priority date attached to the present application, own and independent inventions, the plaintiff reserves the right to make them the object of other independent claims or divisional applications. These objects may also contain independent inventions that represent a configuration independent of the objects of the preceding subclaims.

The exemplary embodiments should not be considered as a limitation of the invention. In contrast to many changes and modifications are possible in the context of the invention as presently exposed, in particular variants, elements and combinations and / or materials which are for example inventive by combination or transformation of the characteristics or elements or steps of the process described in the general description and the embodiments as well as the claims and contained in the drawings and which lead to characteristics that are combinable with a new object or with new process steps or process step sequences, in the it also relates to manufacturing processes, verification and machining, and where it would allow the skilled person to provide a solution to the problem underlying the invention.

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Claims (36)

1. A motor vehicle comprising a drive motor, a torque transmission device (4) having a first actuator, a gearbox (6) having an input shaft and an output shaft and a second actuating device, characterized in that the gearbox comprises a multiplicity of groups of gears forming reduction stages and which are respectively formed by a gear pinion rigidly connected to a shaft and by a pinion gear can be connected to a that a control device is provided and that the first and second actuators can be controlled automatically in a manner controlled by the control device. 2. Motor vehicle comprising a drive motor, a torque transmission device (4) comprising a first actuating device, a gearbox (6) comprising a second actuating device and having a plurality of stages. and a control device, and wherein the first and second actuators can be automatically controlled in a triggered manner by the control device until two reduction stages can be operated by means of a control device. of the same switching element, that for executing a gear ratio change a switching movement and possibly a selection displacement of an actuating element are required, and a change in the gearing ratio includes the steps comprising - the release of the old gear ratio, - possibly the selection of a new gear ment switch, - the engagement of the new gear stage, characterized in that a disengagement of an old gear ratio and engagement of a new gear stage can <Desc / Clms Page number 30>  to be actuated by means of the same switching element, are executed at least without a significant selection displacement component. 3. Motor vehicle according to either of claims 1 and 2, characterized in that the disengagement of an old gear stage and the engagement of a switching element of a new gear stage can be actuated by means of the same switching element are carried out without the actuating element passing in the meantime from the neutral position. A motor vehicle having a torque transmitting device (4) having a first actuator, a gearbox (6) having a second actuator having a multiplicity of gear stages, and a device in which the first and second actuators can be automatically controlled in a triggered manner by the controller and gear stage changes are made in accordance with characteristic curves stored in a memory associated with the control device, characterized in that during an operating mode switching phase of the drive motor, the first actuator and / or the second actuator is (are not) not controlled (s). Motor vehicle according to either of Claims 1 and 4, characterized in that a part of the control device, which is associated with the drive motor (2), transmits to a part of the control device. , associated with the gearbox (6), information relating to an applied switching of the operating mode of the drive motor. 6. Motor vehicle according to claim 5, characterized in that the transmission of information between the parts of the control device is effected at intervals. Motor vehicle according to claim 6, characterized in that the information concerning an applied operating mode switching of the drive motor is transmitted during at least one transmission interval before the switching operation is initiated. <Desc / Clms Page number 31>  8. Motor vehicle according to claim 5, characterized in that the information concerning an applied switching of the operating mode of the drive motor is transmitted for 1 ms to 1 s, in particular for 10 to 50 ms, before the triggering of the switching. 9. Motor vehicle comprising a driving motor, a torque transmission device (4) comprising a first actuating device, a gearbox (6) comprising a second actuating device, which has a plurality of stages and a control device, and wherein the first and second actuators can be automatically controlled in a triggered manner by the control device and changes in reduction stages are made in accordance with curves. characteristics, and wherein at least a first set of characteristic curves, which comprises at least one characteristic curve, is fixedly stored in a memory associated with the controller and at least a second set of characteristic curves, comprising at least a characteristic curve, is adapted, in an adaptive manner, on the basis of a short delay or a significant delay, characterized in that the driver has the possibility to choose between the use of the first set or the second set of characteristic curves. 10. Motor vehicle according to either of claims 8 and 9, characterized in that at least one characteristic curve of the second set can be transferred into at least the first set. 11. Motor vehicle according to claim 10, characterized in that one can modify the at least one transferred characteristic curve, can be made an inscription superimposed on this curve or can be erased. 12. Motor vehicle according to claim 11, characterized in that the at least one characteristic curve can be erased only when it is not active. 13. Motor vehicle according to claim 12, characterized in that instead of the at least one characteristic curve appears, after <Desc / Clms Page number 32>  the erasure of this curve, at least one other characteristic curve stored in the memory. 14. Motor vehicle comprising a drive motor, a torque transmission device (4) comprising a first actuating device, a gearbox (6) comprising a second actuating device, which comprises a plurality of stages. and a control device, and in which the first and second actuator devices are controllable in an automated manner, in a manner triggered by the control device, in accordance with characteristic curves, in a manner corresponding to the least to a displacement program, characterized in that during a predetermination for the selection of a gear stage is attempted to engage this gear stage and in the case of non-availability, it engages a gear stage of demultiplication replacement. 15. Motor vehicle according to any one of claims 1 to 14, characterized in that engages, as a replacement, the next higher gear stage. 16. Motor vehicle according to any one of claims 1 to 14, characterized in that - in the case where the reduction stage currently engaged is the highest gear stage - is engaged as a replacement the lower gear stage. 17. Motor vehicle according to any one of claims 1 to 14, characterized in that - in the case where the reduction stage currently engaged is a reverse gear - is substituted as the position neutral. 18. Motor vehicle according to any one of claims 1 or 14 to 17, characterized in that the reduction stage engaged as a replacement remains engaged until, in accordance with the traveling program, a gear stage other a gear stage not available must be engaged. 19. Motor vehicle according to any one of claims 1 or 14 to 18, characterized in that in the case of a new predetermination for the selection of a reduction stage not available <Desc / Clms Page number 33>  previously, it is desirable again to engage this reduction stage to the extent that we have already left the replacement stage. 20. Motor vehicle comprising a drive motor, a transmission device (4) comprising a first actuating device, a gearbox (6) comprising a second actuating device, which comprises a multiplicity of stages. and a control device, and wherein the first and second actuators can be controlled automatically, in a manner triggered by the controller, and the controller can act to control the motor. characterized in that during a gear change, a determined motor torque and / or a determined torque gradient are required by the control device. Motor vehicle according to either of Claims 1 and 20, characterized in that the required motor torque is greater than the minimum torque (creep torque) of the drive motor (2). 22. Motor vehicle according to claim 21, characterized in that the required motor torque depends on at least one parameter. 23. Motor vehicle according to claim 22, characterized in that the at least one parameter is a displacement program, a position (14) of the load lever, a set point, a real gear, a type of driver and / or a degree of sportiness. 24. Motor vehicle according to claim 23, characterized in that the required motor torque increases when the position (14) of the load lever increases and / or that the torque gradient decreases in absolute value. 25. Motor vehicle according to claim 23, characterized in that the motor torque required in the case of a sports driver or in the case of appropriate adaptation is comparatively high and / or the torque gradient is comparatively low in absolute value. . 26. Motor vehicle comprising a drive motor, a torque transmission device (4) comprising a first actuating device, a gearbox (6) comprising a second device <Desc / Clms Page number 34>  actuator, which has a multiplicity of gear ratios, a control device and wheels with which rotational speed sensors are associated, and in which a wheel slip is identifiable and the first and second actuators can be to be controlled automatically in a manner triggered by the control device, characterized in that even in the case of wheel slip, changes in the gear ratio are performed in accordance with the effective speed of the vehicle. Motor vehicle according to either of Claims 1 and 26, characterized in that the vehicle speed is determined in a standard manner from the sensor signal (60, 61) of the speed of rotation of the vehicle. the wheel (12), which signals the maximum speed. 28. Motor vehicle according to any one of claims 1, 26 and 27, characterized in that the speed of the vehicle in a state where the wheels spin, is determined from the last valid speed of the vehicle and / or from the signal of a sensor (63) of the rotational speed of a non-driven wheel (65). 29. Motor vehicle comprising a drive motor, a torque transmission device (4) comprising a first actuating device, a gearbox (6) comprising a second actuating device, and having an input shaft an output shaft as well as a multiplicity of reduction stages - also including a reverse stage - and a control device, and wherein the first and second actuators can be controlled in an automated manner; a manner triggered by the control device, characterized in that the engagement of a reverse stage only occurs when the difference of the rotational speeds between the input shaft and the output shaft is at least approximately zero. 30. Motor vehicle according to either of claims 1 and 29, characterized in that prior to the engagement of a reverse stage, it expects the flow of a certain time of inertia, in function of at least one parameter. <Desc / Clms Page number 35>  31. Motor vehicle according to claim 30, characterized in that the at least one parameter is an initial difference between the rotational speeds of the input shaft and the output shaft and / or a temperature of the transmission box. speeds. 32. Motor vehicle according to claim 31, characterized in that in the case of a gearbox temperature between 40 C and 200 C and in particular between 80 C and 120 C for each difference of 1000 min-1 between them. rotational speeds, it is expected the flow of a time of inertia less than 10 s and in particular between 0.5 s and 2 s. Motor vehicle comprising a drive motor, a torque transmission device (4) comprising a first actuating device, a gearbox (6) comprising a second actuating device, and comprising a plurality of stages. gear, and a control device, the control of the second actuating device being carried out in an automated manner, being triggered by the control device, in an automatic operating state or else taking place, in a type manual operation, by means of a driver action at the control device, characterized in that possibly a change is made automatically to go into the automatic operating mode. Motor vehicle according to either of Claims 1 or 33, characterized in that the automatic operating mode, on which automatic switching takes place, is a type of emergency operation. 35. Motor vehicle according to claim 34, characterized in that in the emergency operation type, the switching frequency is reduced and / or the number of available reduction stages is limited. Motor vehicle according to either of Claims 1 and 33, characterized in that, in the event of a fault or a faulty state of one or more components, the operation is switched to the type automatic operation.