DE10354289A1 - Traction behavior device e.g. for driving wheels of vehicle, arranged in vehicle having axles connected to steering axle and driving axles connected to shafts and drive slip regulator which is controlled by computer system - Google Patents

Abstract

The device is arranged in a vehicle having axles connected to a steering axle. The driving axles are connected to shafts and a drive slip regulator which is controlled by a computer system. The regulator controls the speed and the braking of the vehicle. An independent claim is included for a method.

Description

The The invention relates to an apparatus and a method for Influencing the traction of drive wheels of a Vehicle. The vehicle has several axles each with associated wheels on, wherein it at least designed to be steerable at the axes Steering axle, one with arranged in the vehicle drive means in Actively connected drive axle and one of the drive axle spatial associated third axis, where axle load influencing means are provided, with which the axle acting on the third axle can be influenced.

Such a device for a motor vehicle is from the document DE 39 29 788 C2 out. The motor vehicle has a steerable front axle and a Doppelachsaggregat, one axis of which can be driven as a driving axis and the other axis lift axle via bellows liftable or relieved, so that the traction on the wheels of the drive axle in the case of smooth or slippery road conditions in terms of Improvement of the traction and thus the driving stability, the steerability and the starting behavior of the motor vehicle can increase targeted. In order to avoid the occurrence of unstable driving conditions in the case of unfavorable traction conditions from the outset, a timely increase or decrease the lift axle is necessary. If the release of the lifting or Entlastungsvor gear of the lift axle in particular left to the driver, unnecessary time delays may result due to driver misjudgments of the road condition or due to the driver-specific reaction behavior, which allow for unfavorable traction conditions skidding, skidding or jamming of the vehicle.

task The present invention is therefore a device or a Process of the type mentioned in such a way that in case of unfavorable traction conditions a timely increase or relief of the lift axle or a Additional axle or load transfer axis is guaranteed.

These Task is performed according to the characteristics of Patent claim 1 or of claim 16 solved.

The equipped with the device according to the invention Vehicle has several axles, each with associated wheels, wherein it is at least designed to be steerable at the axes Steering axle, one with arranged in the vehicle drive means in Actively connected drive axle and one of the drive axle spatial assigned third axis acts. Here are axle load influencing means provided with which acting on the third axis axle load can be influenced. The vehicle may be, for example a van, a tractor and a trailer or a trailer Semi-trailer existing vehicle combination, a one-piece truck or to trade a bus. According to the invention, the vehicle additionally comprises traction slip influencing means on, with those at fulfillment one for the at the wheels the drive axle, i. at the drive wheels of the vehicle, present Drive slip predetermined condition of the drive slip through driver-independent Interference in the wheels the drive axle associated braking means and / or in the drive means is reduced, wherein in the presence of a defined state the traction control means the axle load influencing means independently of the driver to reduce the axle load acting on the third axle become. By appropriate definition of the state of the traction slip influencing means let yourself in case of unfavorable traction conditions a timely increase or discharge of the third axis or ensure the additional axle or load transfer axle. With the traction slip influencing means in particular, it may be a common one and thus in its function proven Traction control (ASR) act. The operation of such Traction control is sufficient from the literature known, so omitted at this point on a detailed description should be (see, for example, "Bosch, Automotive Paperback ", 23. Edition, p. 606 ff.).

advantageous versions the device according to the invention are apparent from the dependent claims.

Advantageously, the defined state of the traction slip influencing means is present when the predefined condition for the traction slip is met and / or if a hint signal is issued by the traction slip influencing means, indicating the implementation of the driver-independent interventions in the braking means and / or in the drive means of the vehicle , and / or if the drive slip influencing means control signals are issued, which are provided for performing the driver-independent interventions in the braking means and / or in the drive means. By appropriate selection or combination of the above-mentioned state conditions, the axle load influencing means can not only avoid unnecessary time delays, but in particular regardless of the personal assessment of the driver in the sense of reducing the axle load acting on the third axle. For outputting the indication signal or the drive signals, the traction slip influencing means have digital and / or analog output drivers, wherein the indication signal output by the output drivers can additionally serve to drive driver information means, which draw the driver's attention to a response of the traction slip influencing means or the traction control system.

at the third axis may in particular be a stroke axis, the with a arranged on the vehicle lifting device in operative connection stands. To influence the axle load, the lifting axle can be adjusted by means of the lifting device in height to the road surface raise or lower, for which the lifting device electrically controlled or having pressure-controlled actuators, which are via suitable control means be driven. The raising or lowering of the lifting axle takes place while complying with the statutory maximum drive axle load the drive axle. In the same way, those for the speed of travel compliance with applicable legal limits.

alternative For example, the third axis may be a load transfer axis acting with a pressure-powered load transfer device is in operative connection, by means of which the axle load by construction or degradation of a ruling in the load transfer device Can influence operating pressure, without significantly changing the load transfer axis in height to the road surface. For this For example, the load transfer device has pressure-operated and about appropriate Control means controllable air spring bellows, as in common air spring systems use of vehicles. The lifting device or the load transfer device is in multi-axle trucks usually to reduce the tire wear available, including the lifting device or the load transfer device respectively associated axle in case of incomplete loading of the truck is raised or relieved.

easily is that for the drive slip predetermined condition then met when the each at the wheels the drive axle occurring traction a predetermined Traction slip threshold exceeds, wherein the drive slip depending on the difference in the speed of travel of the vehicle and the peripheral speed of the wheels of the Drive axle results.

Around to prevent already a short-term occurring and thus uncritical drive slip for lifting or relieving the third axis leads, solve first the traction slip influencing means the driver-independent interventions into and out of the braking means and / or the drive means if the drive slip still occurs on the wheels of the drive axle, becomes the driver independent Reduction of the axle load by controlling the axle load influencing means performed.

The previously described temporal sequence can in particular under compliance a given time delay, in such a way that the control of the axle load influencing means for the reduction the axle load is only made when the release of the driver-independent Intervention in the braking means and / or in the drive means elapsed Time exceeds a given time threshold. This ensures that the impact on the axle load is carried out exclusively if the driver independent Intervention in the brake means and / or in the drive means in the time defined by the time threshold not to the desired reduction the drive slip lead. The time defined by the time threshold is typically this in the order of magnitude of 1 second, i. it can be chosen slightly larger or smaller than 1 second.

alternative there is also the possibility that the control of the axle load influencing means for the reduction The axle load only takes place when the defined state of the Drive slip influencing means already for a predetermined Minimum time is present, so that one of the driver-independent interventions in the braking means and / or in the drive means independent time for the Defining reduction of the axle load.

The Axle load influencing means are for example driven in such a way, that the influence of the axle load takes place in a predefined way, in particular by simply lifting or relieving the third Axis until reaching a fixed final or switch-off point. However, the axle load influencing means can also be activated in this way be that influencing the axle load in dependence at the wheels the drive axle present traction occurs, for example in such a way that the axle load only reduces as much as required until the for the Drive slip predetermined condition is just no longer satisfied.

Thus, in the case of high speeds a destabilization of the vehicle due to a change in the individual axes we kenden loads is excluded, there is the possibility that the axle load influencing means are influenced to influence the axle load only when the vehicle speed is less than a predetermined cruise speed threshold. The cruise speed threshold is typically on the order of 20 to 40 kilometers per hour.

advantageously, is an already made influencing or reducing the axle load independently maintained by the operating state of the traction control means or at least not undone. A renewed increase traction slip, especially in the case of a reversed Reducing the axle load could occur and under some circumstances repeated response of the traction slip influencing means would cause becomes reliable in this way avoided. exceeds the driving speed of the vehicle, however, a predetermined Cruise speed threshold, which is preferably identical to the aforementioned Cruise speed threshold is the one already made Influencing the axle load, in particular the already made Reduction of the axle load by suitable lowering or loading undone the third axis, so an impairment the driving dynamics of the vehicle at high speeds can be excluded due to the reduced axle load.

Next the axle load influencing means may further Antriebsachslastbeeinflussungsmittel be present, the Antriebsachslastbeeinflussungsmittel to Influencing a drive axle load acting on the drive axle are provided. This allows changes in the position of the vehicle, the caused due to the raised or relieved third axis become noticeable by a "sagging" of the rear of the vehicle, compensate by suitable lowering or loading of the drive axle.

The Control of the axle load influencing means is preferably carried out directly by the traction slip influencing means, so the device according to the invention in vehicles where both the traction slip control means as the axle load influencing means already exist, can be retrofitted with comparatively little effort.

The inventive device or the inventive method will be explained in more detail below with reference to the accompanying drawings. there demonstrate:

1 a schematically illustrated embodiment of the device according to the invention,

2 an embodiment of the method according to the invention in the form of a flow chart.

1 shows a schematically illustrated embodiment of the device according to the invention for influencing the traction of drive wheels of a vehicle. The vehicle 10 has several axes 11a to 11c each with associated wheels on. At the axles 11a to 11c it is at least one steerable steering axle 11c , one with in the vehicle 10 arranged drive means 12 operatively connected drive axle 11a and one of the drive axle 11a spatially assigned third axis 11b , wherein Achsbeeinflussungsmittel 13 are provided, with which the on the third axis 11c acting axle load F → ' _A. At the wheels of the third axle 11c These are freely rolling or non-driven wheels.

According to the invention, the vehicle comprises 10 continue to drive slip influencing means 14 directly related to the axle load influencing means 13 be in operative connection and which may be in particular a conventional traction control (ASR). As an alternative to the above variant, the traction slip influencing means 14 also via a higher-level controller which provides an interface between the traction slip influencing means 14 and the axle load influencing means 13 forms and takes over coordination tasks, with the axle load influencing means 13 in operative connection.

wobei λ den Antriebsschlupf, v_f die Fahrtgeschwindigkeit des Fahrzeugs 10 und v_u die Umfangsgeschwindigkeit der Räder der Antriebsachse 11a bezeichnet.The traction slip influencing means 14 have an evaluation unit 15 and wheel speed sensors 16 on which the wheel speeds of the wheels of the steering axle 11c or the wheel speeds of the wheels of the drive axle 11a capture and generate corresponding wheel speed signals that the evaluation 15 for determining the at the wheels of the drive axle 11a be supplied to this drive slip. The evaluation unit 15 determined on the basis of the wheel speed signals a speed of travel, the speed of the vehicle 10 describes, and a peripheral speed that the peripheral speed of the wheels of the drive axle 11a describes. The determination of the drive slip or a drive slip quantity describing the drive slip then takes place using a relationship of the form

where λ is the traction slip, v _{f is} the travel speed of the vehicle 10 and v _{u is} the peripheral speed of the wheels of the drive axle 11a designated.

Make the traction slip influencing means 14 by evaluating the traction slip or the traction slip quantity describing the traction slip, it is satisfied that a traction slip occurring at the wheels of the drive axle exceeds a predetermined traction slip threshold, so that the traction slip influencing means reduce 14 the at the wheels of the drive axle 11a present drive slip by driver-independent intervention in the wheels of the drive axle 11a associated brake means 20 and / or in the drive means 12 , wherein the evaluation unit 15 in the presence of a defined state of the traction slip influencing means 14 the axle load influencing means 13 Driver independent to reduce to the third axle 11c acting axle load F → ' _A drives, so that the on the drive axle 11a acting drive axle load F → _A and thus the traction on the wheels of the drive axle 11a increases.

The defined state of the traction slip influencing means 14 is for example present when the predetermined condition for the traction slip is met and / or when the traction slip influencing means 14 emit a warning signal indicating the implementation of the driver-independent interventions in the braking means 20 and / or in the drive means 12 of the vehicle 10 indicates, and / or if the traction slip influencing means 14 Issuing control signals, which are used to carry out the driver-independent interventions in the braking means 20 and / or in the drive means 12 are provided. For delivery of the indication signal or the drive signals, the evaluation unit 15 digital and / or analog output drivers. The hint signal emitted by the output drivers additionally serves to control driver information means 21 to alert the driver to a response of the traction control means 14 to draw attention.

At the third axis 11b For example, this is a load transfer axis that coincides with one on the vehicle 10 arranged load transfer device 22 is in operative connection, wherein by means of the load transfer device 22 on the third axis 11b acting axle load F → ' _A by setting up or dismantling one in the load transfer device 22 can be influenced by the prevailing operating pressure. For this purpose, the load transfer device 22 pressure-operated bellows of an air spring system, which is controlled by a control unit 23 by appropriate influencing one of a reservoir pressure vessel 24 fed pressure valve assembly 25 be driven. To reduce to the third axis 11b acting axle load F → ' _A closes the control unit 23 in a first step, a first pressure valve 25a and a second pressure valve 25b Thereafter, in a second step, a first pressure relief valve 25c to open, causing degradation in the load transfer device 22 prevailing operating pressure and thus to relieve the third axis 11b leads. Next to the first pressure relief valve 25c is another, second pressure relief valve 25d shown, which is in a static, closed state in connection with the above-described influence of the axle load F → ' _A.

It should be mentioned at this point that the influence of the load transfer device 22 by building or reducing the operating pressure only to a negligible change in the height of the load transfer axis relative to the road surface 30 leads. The in the 1 illustrated significant height variation of the load transfer axis should therefore serve primarily better illustration.

Instead of the load transfer axis can also be provided a lifting axle, which with one on the vehicle 10 arranged lifting device is in operative connection. To influence the axle load F → ' _A , the lifting axle can be adjusted by means of the lifting device in its height to the road surface 30 raise or lower, for which purpose the lifting device has electrically controlled or pressure-controlled actuators. In the case of pressure-controlled actuators, the structure of the axle load influencing means 13 largely identical to that of 1 whereas in the case of electrically controlled actuators, the pressure valve arrangement 25 is to be replaced by a corresponding arrangement of electrical switching elements, such as relays or semiconductor switches.

In order to prevent even a momentarily occurring and thus uncritical traction slip to raise or relieve the third axis 11b leads, first solve the traction slip influencing means 14 the driver-independent interventions in the braking means 20 and / or in the drive means 12 out and only then, provided continue the drive slip on the wheels of the drive axle 11a occurs, the driver-independent reduction of the axle load F → ' _A by controlling the axle load influencing means 13 performed.

The time sequence described above takes place while maintaining a predetermined time delay, in such a way that the control the axle load influencing means 13 to reduce the axle load F → ' _{A is} only carried out if since the driver-independent interventions in the braking means 20 and / or in the drive means 12 elapsed time, which is detected by means of a time counter, exceeds a predetermined time threshold. Alternatively, the control of the axle load influencing means takes place 13 for reducing the axle load F → ' _A only when the defined state of the traction slip influencing means 14 already exists for a given minimum time.

The traction slip influencing means 14 control the axle load influencing means 13 either in such a way that influencing the axle load F → ' _A in a fixed manner by relieving or lifting the third axis 11b until reaching a fixed predetermined switch-off or end point, or in such a way that the influence of the axle load F → ' _A in dependence on the wheels of the drive axle 11a present traction slip is made, for example, such that the axle load F → ' _A according to the need is only reduced so far until the predetermined condition for the traction slip is just no longer met. The achievement of the respective switch-off or end point is suitably arranged by evaluation of the switching or sensor signals and with the evaluation unit 15 operatively connected limit switch 31 or load sensors 32 recognized.

An influencing of the axle load F → ' _A in a predetermined manner is preferably carried out in the form of a complete unloading or raising of the third axle 11b , To maintain stable driving conditions, the complete lifting or unloading of the third axle 11b only made if it is ensured that the case at the drive axle 11a occurring drive axle load F → _A does not exceed a maximum permissible limit value. This maximum permissible limit corresponds in the case of a vehicle combination or one-piece truck with three axes, for example, a mass of 13 Metric tons. Also, the influence of the axle load F → ' _A as a function of the wheels of the drive axle 11a The present drive slip is such that the case of the drive axle 11a occurring drive axle load F → _A does not exceed a maximum permissible limit value.

Represents the evaluation unit 15 by evaluating the determined speed of travel speed determines that the driving speed of the vehicle 10 is greater than a predetermined threshold value, the reduction of the axle load F → ' _A is omitted. An already made reduction of the axle load F → ' _A , however, is independent of the operating state of the traction slip influencing means 14 maintained. Only when the evaluation unit 15 determines that the driving speed of the vehicle 10 exceeds the predetermined cruise speed threshold, the already made reduction of the axle load F → ' _A by appropriate loading or lowering the third axis 11b Undone.

According to the example, in addition to the axle load influencing means 13 continue Antriebsachslastbeeinflussungsmittel 33 provided, wherein it is at the Antriebsachslastbeeinflussungsmitteln 33 one for influencing the drive axle 11a acting drive axle load F → _A provided load transfer device is, in particular the drive axle 11a associated with air suspension bellows, which are part of the air spring system. The activation of the drive axle load influencing means 33 also takes place via the control unit 23 by appropriate influencing of the pressure valve arrangement 25 in such a way that as a result of the discharge or

Raising the third axis 11b occurring position change of the vehicle 10 , which is noticeable in the form of a "sagging" of the rear of the vehicle, is compensated, the latter being achieved by appropriately loading or lowering the drive axle 11a So by increasing the on the drive axle 11a acting drive axle load F → _A achieved what the in the load displacement device of the drive axle 11a prevailing operating pressure is increased until it reaches a balanced level of the vehicle, which corresponds to its construction situation.

Regardless, it is also conceivable by means of the Antriebsachslastbeeinflussungsmittel 33 on the steering axle 11c acting steering axle load F → _V to improve the cornering force of the wheels of the steering axle 11c increase by the drive axle load F → _A by appropriately loading or lowering the drive axle 11a is raised.

A manual release of the described reduction of the axle load F → ' _A is via a with the control unit 23 connected switch 34 possible, so that the driver with incomplete loaded vehicle 10 in the usual way the tire wear by relieving or lifting the third axis 11b can reduce.

At this point it should be noted that in connection with 1 chosen embodiment of the vehicle with three axes should have no limiting effect. The use of the method and the device according to the invention in a vehicle with more than three axes is also conceivable.

2 shows an embodiment of the method according to the invention in the form of a flow chart. After starting the process in an initialization step 40 , in which, inter alia, a reset of the time counter takes place, is in a first main step 41 checks whether the predetermined condition for the traction slip is fulfilled. If this is not true, in a first secondary step 51 on the one hand reset the time counter, provided that this has a different value from the reset state, which is the case for example, if the first main step 41 not for the first time, and on the other hand, possibly existing, intended to reduce the drive slip driver-independent interventions in the braking means 20 and / or in the drive means 12 completed. Subsequently, the process flow returns to the first main step 41 back. Will be in the first main step 41 it has been determined that the condition specified for the traction slip is fulfilled, is terminated with a second main step 42 continued, in which on the one hand, the time counter is incremented by a predetermined amount and in the other hand, on the wheels of the drive axle 11a present drive slip by triggering in connection with 1 described driver-independent interventions in the braking means 20 and / or in the drive means 12 is reduced.

Will be in one to the second main step 42 subsequent third main step 43 it is determined that the time counter exceeds a threshold value corresponding to the predetermined time threshold value, with a fourth main step 44 proceeding, it is further checked in on whether the travel speed described by the traveling speed v of the vehicle size _f 10 is less than the predetermined cruise speed threshold v _{f, ref} . If this is the case, in a fifth main step 45 on the third axis 11b acting axle load F → ' _A by controlling the axle load influencing means 13 reduced. On the other hand, one of the two hits in the main steps 43 and 44 given conditions, the procedure returns to the first main step 41 back to start over.

On the fifth main step 45 follows a sixth main step 46 , It is checked in which whether the driving speed schwindigkeitsgröße described by the Fahrtge _f v the speed of travel predetermined threshold value _{f v, ref} exceeds. If this is the case, in a second substep 52 the reduction of the axle load F → ' _A reversed, and the procedure returns to the first main step 41 back. Otherwise, with a seventh main step 47 in which it is determined whether the predetermined condition for the traction slip is met, wherein when the condition is fulfilled, the driver-independent intervention in the braking means 20 and / or in the drive means 12 in a third side step 53 be continued and the procedure for the fifth main step 45 returns. If, on the other hand, the condition specified for the traction slip is not fulfilled, then in an eighth main step 48 the driver-independent interventions in the braking means 20 and / or in the drive means 12 terminated, whereupon the procedure also for the fifth main step 45 returns. An already made reduction of the axle load F → ' _A thus remains independent of the operating state of the traction slip influencing means 14 maintained.

Claims (16)

Device for influencing the traction behavior of drive wheels of a vehicle, wherein the vehicle ( 10 ) several axes ( 11a . 11b . 11c ) each having associated wheels, wherein the axes ( 11a . 11b . 11c ) at least about a steerable steering axle ( 11c ), one in the vehicle ( 10 ) arranged drive means ( 12 ) operatively connected drive axle ( 11a ) and one of the drive axle ( 11a ) spatially associated third axis ( 11b ), where axle load influencing means ( 13 ) are provided, with which on the third axis ( 11b ) acting axle load (F → ' _A ), characterized in that the vehicle ( 10 ) additionally traction slip influencing means ( 14 ), in particular a traction control system, with which upon fulfillment of one of the at the wheels of the drive axle ( 11a ) present drive slip predetermined condition of the drive slip by driver-independent interventions in the wheels of the drive axle ( 11a ) associated brake means ( 20 ) and / or in the drive means ( 12 ) is reduced, wherein in the presence of a defined state of the traction slip influencing means ( 14 ) the axle load influencing means ( 13 ) Driver-independent for the reduction to the third axis ( 11b ) acting axle load (F → ' _A ). Apparatus according to claim 1, characterized in that the defined state of the traction slip influencing means ( 14 ) is present when the predetermined condition for the traction slip is fulfilled and / or if by the traction slip influencing means ( 14 ) a warning signal is issued, which is based on the implementation of the driver-independent interventions in the braking means ( 20 ) and / or in the drive means ( 12 ), and / or if by the traction slip influencing means ( 14 ) Control signals are issued, which are used to carry out the driver-independent interventions in the braking means ( 20 ) and / or in the drive means ( 12 ) are provided. Apparatus according to claim 1, characterized ge indicates that the third axis ( 11b ) is a lifting axis, wherein the lifting axis is in operative connection with a lifting device, by means of which the lifting axis in its height to the road surface ( 30 ) to raise or lower the axle load (F → ' _A ). Device according to Claim 1, characterized in that, in the case of the third axis ( 11b ) is a load transfer axis, wherein the load transfer axis with a pressure-operated load transfer device ( 22 ) is in operative connection, by means of which the axle load (F → ' _A ) by building or dismantling a in the load transfer device ( 22 ) can be influenced by prevailing operating pressure. Device according to claim 1, characterized in that the condition predetermined for the traction slip is fulfilled when the wheel is mounted on the wheels of the drive axle ( 11a ) occurring drive slip exceeds a predetermined traction slip threshold. Apparatus according to claim 1, characterized in that for influencing the traction behavior of the wheels of the drive axle ( 11a ) first the traction slip influencing means ( 14 ) the driver-independent interventions in the braking means ( 20 ) and / or in the drive means ( 12 ) and only then the driver-independent reduction of the axle load (F → ' _A ) by controlling the axle load influencing means ( 13 ) is made. Apparatus according to claim 6, characterized in that the control of the axle load influencing means ( 13 ) to reduce the axle load (F → ' _A ) takes place only when, since the triggering of the driver-independent interventions in the braking means ( 20 ) and / or in the drive means ( 12 ) elapsed time exceeds a predetermined time threshold. Apparatus according to claim 1, characterized in that the control of the axle load influencing means ( 13 ) for reducing the axle load (F → ' _A ) takes place only when the defined state of the traction slip influencing means ( 14 ) has been present for a predetermined minimum time. Device according to claim 1, characterized in that the axle load influencing means ( 13 ) are controlled in such a way that the influencing of the axle load (F → ' _A ) either in a fixed predetermined manner or depending on the at the wheels of the drive axle ( 11a ) present slip occurs. Device according to claim 1, characterized in that the axle load influencing means ( 13 ) are influenced to influence the axle load (F → ' _A ) only when the vehicle speed (v _f ) ( 10 ) is less than a predetermined vehicle speed threshold (v _{f, ref} ). Apparatus according to claim 1, characterized in that an already made influencing the axle load (F → ' _A ) regardless of the operating state of the traction slip influencing means ( 14 ) is maintained. Device according to Claim 1, characterized in that any influence already made on the axle load (F → ' _A ) is reversed if the speed of travel (v _f ) of the vehicle ( 10 ) exceeds a predetermined vehicle speed threshold (V _{f, ref} ). Apparatus according to claim 1, characterized in that in addition to the axle load influencing means ( 13 ) continue to drive axle load influencing means ( 33 ), the drive axle load influencing means ( 33 ) for influencing one on the drive axle ( 11a ) acting drive axle load (F → _A ) are provided. Apparatus according to claim 1, characterized in that the control of the axle load influencing means ( 13 ) directly by the traction slip influencing means ( 14 ) he follows. Motor vehicle equipped with a device according to one of the preceding claims. Method for influencing the traction behavior of drive wheels of a vehicle, wherein the vehicle ( 10 ) several axes ( 11a . 11b . 11c ) each having associated wheels, wherein the axes ( 11a . 11b . 11c ) at least about a steerable steering axle ( 11c ), one in the vehicle ( 10 ) arranged drive means ( 12 ) operatively connected drive axle ( 11a ) and one of the drive axle ( 11a ) spatially associated third axis ( 11b ), with the third axis ( 11b ) acting axle load (F → ' _A ), characterized in that the vehicle ( 10 ) additionally traction slip influencing means ( 14 ), in particular a traction control system, with which at the wheels of the drive axle ( 11a ) present driving slip by driver-independent interventions in the wheels of the drive axle ( 11a ) associated brake means ( 20 ) and / or in the drive means ( 12 ), if it is found that one for the wheels of the drive axle ( 11a ) given driving slip predetermined condition is met, whereby the on the third axis ( 11b ) axle load (F → ' _A ) is reduced, if it is determined that a defined state of the traction slip influencing medium ( 14 ) is present.