DE202016002576U1 - Antriebsabschaltsteuerung for a motor vehicle and motor vehicle - Google Patents

Abstract

A drive shut-off control for a motor vehicle (2), wherein the motor vehicle (2) has a drive (6) and an electric power assistance (8), wherein the drive shut-off control (4) is connected to a steering angle sensor (14), the drive shut-off control (4) thereto is configured to calculate a steering angle gradient from at least two steering angle sensor measurements, wherein the drive shut-off control (4) is adapted to derive a steering torque from a steering angle gradient on a steering wheel (12) of the motor vehicle (2), the drive shut-off control (4) being arranged to in a) exceeding a first limiting steering torque to prevent a shutdown of the drive (6) and / or b) exceeding a second Grenzlenkmoments to force an activation of the drive (6).

Description

Described are a Antriebsabschaltsteuerung for a motor vehicle and a corresponding motor vehicle with Antriebsabschaltsteuerung.

Motor vehicles have been equipped for quite some time often with automatic drive shutdowns. Known drive shutdowns provide for a shutdown of the drive in a stationary motor vehicle in order to save energy, if no energy of the drive is needed. The drive is u. a. not required if an interior climate is in a driver-selected area and if the state of charge of a motor vehicle battery has a certain minimum value.

For some time, motor vehicles have been known which can switch off a drive during a driving operation, as long as no propulsion is needed. The drive is then decoupled from the wheels and the vehicle can roll freely. This is the case, for example, in the case of an upcoming curve, before which a motor vehicle must brake. This condition is often referred to as "sailing".

For the former case of a drive shutdown of a stationary vehicle discloses the US 9,043,119 B2 a breaking device having an information supply unit having information between components of a power steering electric power device having a drive, a steering torque sensor, a rotation sensor and drive motor speed sensor, wherein a drive unit is provided, which is adapted to a predetermined range of steering torque and a rotational speed of an output shaft Recognize steering, wherein the control unit assesses whether there is a status in which a steering wheel is stabilized by a user, operated or held against a stop, wherein, when the drive torque and the rotational speed of an output shaft are below the predetermined values, a Abschalterlaubnis decision is made ,

In particular, in a moving vehicle, so in sailing mode, it is important that the driver always retains control of the motor vehicle. It should not be surprised when switching off the motor vehicle by a sudden change in the steering torque to be introduced via the steering wheel, which is perceived by the driver as a steering kickback. This could endanger driving safety.

Thus, the task of developing methods and devices of the type mentioned in such a way that a safe shutdown operation is possible even when the motor vehicle.

The object is achieved by a Antriebsabschaltsteuerung for a motor vehicle according to claim 1 and by a motor vehicle with a Antriebsabschaltsteuerung according to the independent claim 4. Further developments are the subject of the respective dependent claims.

• a. Überschreiten eines ersten Grenzlenkmoments eine Abschaltung des Antriebs zu unterbinden und/oder
• b. Überschreiten eines zweiten Grenzlenkmoments eine Aktivierung des Antriebs zu forcieren.

A first independent subject matter relates to a drive shutdown control for a motor vehicle, the motor vehicle having a drive and an electric steering assist, the drive shutoff control being connected to a steering angle sensor, the drive shutoff control configured to calculate a steering angle gradient from at least two steering angle sensor measurements, wherein the drive shutdown control is adapted to derive from the steering angle gradient, a steering torque on a steering wheel of the motor vehicle, wherein the Antriebsabschaltsteuerung is further adapted to, at

• a. Exceeding a first limiting steering torque to prevent a shutdown of the drive and / or
• b. Exceeding a second Grenzlenkmoments to force an activation of the drive.

In this way, a shutdown of the drive is only allowed in the former case, if a certain Grenzlenkmoment is not exceeded. Thus, a sudden jump of the steering torque on the steering wheel in case of failure of the power steering can be prevented, which could surprise the driver of the motor vehicle, which would adversely affect driving safety.

For the second case, when a limiting steering torque is exceeded, an activation of the drive can be forced, for example when the driver steers into a curve during sailing operation. In this way, a power steering can be offered without that an accumulator of the motor vehicle must be charged.

• a. Überschreiten eines ersten Grenzlenkwinkels eine Abschaltung des Antriebs zu unterbinden und/oder
• b. Überschreiten eines zweiten Grenzlenkwinkels eine Aktivierung des Antriebs zu forcieren.

In a further possible embodiment, the drive shutdown control can be set up at

• a. Exceeding a first limiting steering angle to prevent a shutdown of the drive and / or
• b. Exceeding a second limiting steering angle to force activation of the drive.

As a result, when the steering angles are too great, a shutdown of the drive can be prevented or, when a second limiting steering angle is exceeded, the drive can be switched on. With increasing steering angle is the Return torque greater, which would lead to a larger setback in the steering.

In particular, a combination of the monitoring of a steering angle gradient and the steering angle itself as independent criteria to prevent the shutdown of a drive or to force the activation of the drive, has the advantage that both static and dynamic effects of the control of the drive shutdown can be considered.

In another further embodiment, it may be provided that the drive shut-off control is connected to a wheel speed sensor for a left wheel and a wheel speed sensor for a right wheel. With appropriate wheel speed sensors can record wheel speeds and / or Raddrehgeschwindigkeiten. In addition, speed differences can be determined.

Thus, driving dynamics aspects that can influence the steering torque on a steering wheel of the motor vehicle, be taken into account.

A first independent subject matter relates to a motor vehicle having a drive shutdown control according to one of the preceding claims.

• 1. Verfahren zum Betrieb eines Kraftfahrzeuges (2) mit einem Antrieb (6), einer Antriebsabschaltsteuerung (4) und einer elektrischen Lenkkraftunterstützung (8), wobei ein Lenkwinkelgradient gemessen wird, wobei aus dem Lenkwinkelgradienten ein Lenkmoment an einem Lenkrad (12) des Kraftfahrzeuges (2) berechnet wird, wobei bei a) Überschreiten eines ersten Grenzlenkmoments eine Abschaltung des Antriebs (6) unterbunden wird und/oder b) Überschreiten eines zweiten Grenzlenkmoments eine Aktivierung des Antriebs (6) forciert wird.
• 2. Verfahren nach Aspekt 1, wobei ein Lenkwinkel gemessen wird, wobei bei a) Überschreiten eines ersten Grenzlenkwinkels eine Abschaltung des Antriebs (6) unterbunden wird und/oder b) Überschreiten eines zweiten Grenzlenkwinkels eine Aktivierung des Antriebs (6) forciert wird.
• 3. Verfahren nach Aspekt 1 oder 2, wobei Raddrehzahlen des linken Rades (20) und des rechten Rades (22) und/oder Raddrehgeschwindigkeiten des linken Rades (20) und des rechten Rades (22) an einer gelenkten Achse (18) des Kraftfahrzeuges (2) gemessen werden und in die Berechnung des Lenkmomentes einfließen.
• 4. Verfahren nach Aspekt 3, wobei aus den Raddrehzahlen des linken Rades (20) und des rechten Rades (22) eine Raddrehzahldifferenz und/oder aus den Raddrehgeschwindigkeiten des linken Rades (20) und des rechten Rades (22) eine Radgeschwindigkeitsdifferenz berechnet wird und in die Berechnung des Lenkmoments einfließt.

Hereinafter, another independent subject will be described. This subject relates to:

• 1. Method for operating a motor vehicle ( 2 ) with a drive ( 6 ), a drive shutdown control ( 4 ) and an electric power steering ( 8th ), wherein a steering angle gradient is measured, wherein from the steering angle gradient, a steering torque on a steering wheel ( 12 ) of the motor vehicle ( 2 ) is calculated, wherein at a) exceeding a first Grenzlenkmoments a shutdown of the drive ( 6 ) is prevented and / or b) exceeding a second limiting steering torque activation of the drive ( 6 ) is forced.
• 2. The method according to aspect 1, wherein a steering angle is measured, wherein at a) exceeding a first limiting steering angle, a shutdown of the drive ( 6 ) is suppressed and / or b) exceeding a second limiting steering angle activation of the drive ( 6 ) is forced.
• 3. The method according to aspect 1 or 2, wherein wheel speeds of the left wheel ( 20 ) and the right wheel ( 22 ) and / or wheel rotational speeds of the left wheel ( 20 ) and the right wheel ( 22 ) on a steered axle ( 18 ) of the motor vehicle ( 2 ) are measured and incorporated into the calculation of the steering torque.
• 4. The method according to aspect 3, wherein from the wheel speeds of the left wheel ( 20 ) and the right wheel ( 22 ) a wheel speed difference and / or from the wheel rotational speeds of the left wheel ( 20 ) and the right wheel ( 22 ) a wheel speed difference is calculated and included in the calculation of the steering torque.

Method according to one of the preceding aspects, wherein first limiting steering torque and second limiting steering torque and / or first limiting steering angle and second limiting steering angle are identical.

In detail:

• a. Überschreiten eines ersten Grenzlenkmoments eine Abschaltung des Antriebs unterbunden wird und/oder
• b. Überschreiten eines zweiten Grenzlenkmoments eine Aktivierung des Antriebs forciert wird.

The invention relates to a method for operating a motor vehicle, the motor vehicle having a drive, a drive shut-off control and an electrical power assistance, wherein a steering angle gradient is measured, wherein a steering torque is calculated from the steering angle gradient on a steering wheel of the motor vehicle

• a. Exceeding a first Grenzlenkmoments a shutdown of the drive is prevented and / or
• b. Exceeding a second Grenzlenkmoments an activation of the drive is forced.

• a. Überschreiten eines ersten Grenzlenkwinkels eine Abschaltung des Antriebs unterbunden wird und/oder
• b. Überschreiten eines zweiten Grenzlenkwinkels eine Aktivierung des Antriebs forciert wird.

In a first further embodiment, it may be provided that a steering angle is measured, wherein at

• a. Exceeding a first limiting steering angle, a shutdown of the drive is prevented and / or
• b. Exceeding a second limiting steering angle activation of the drive is forced.

In a further embodiment, wheel speeds of the left wheel and the right wheel and / or wheel speeds of the left wheel and the right wheel on a steered axle of the motor vehicle can be measured and incorporated into the calculation of the steering torque.

In another further embodiment, it can be provided that a wheel speed difference is calculated from the wheel speeds of the left wheel and the right wheel and / or a wheel speed difference is calculated from the wheel speeds of the left wheel and the right wheel and incorporated into the calculation of the steering torque. As a result, other influencing factors can be determined, which can change the steering torque on the steering wheel.

In another further embodiment, it may be provided that the first limiting steering torque and the second limiting steering torque and / or the first limiting steering angle and the second limiting steering angle are identical. In this way, the process can be made simpler.

Another independent object relates to an apparatus for operating a motor vehicle, having a drive, a drive shut-off and an electric power steering, wherein means for measuring a steering angle gradient are provided, wherein means are provided to the steering angle gradient of a steering torque to a steering wheel of the motor vehicle wherein means are provided for inhibiting a shutdown of the drive when a first Grenzlenkmoments is exceeded and / or means for forcing an activation of the drive at a second Grenzlenkmoments exceeded.

A first further embodiment of the device provides that means for measuring a steering angle are provided, wherein the means for inhibiting the shutdown of the drive are active when a first Grenzlenkwinkels is exceeded and / or that the means for activating the drive provided when exceeding a second Grenzlenkwinkels are.

In another further embodiment, means for detecting wheel speeds of the left wheel and the right wheel and / or means for detecting wheel speeds of the left wheel and the right wheel on a steered axle of the motor vehicle may be provided, which are incorporated into the calculation of the steering torque.

In another further embodiment, computing means can be provided which can calculate a wheel speed difference from the wheel speeds of the left wheel and the right wheel and / or from the wheel speeds of the left wheel and the right wheel a Raddrehgeschwindigkeitsdifferenz, the difference flows into the calculation of the steering torque ,

In a further embodiment, the first limiting steering torque and the second limiting steering torque and / or the first limiting steering angle and the second limiting steering angle may be identical.

Further features and details will become apparent from the following description, in which - where appropriate, with reference to the drawings - at least one embodiment is described in detail. Described and / or illustrated features form the subject matter, or independently of the claims, either alone or in any meaningful combination, and in particular may additionally be the subject of one or more separate applications. The same, similar and / or functionally identical parts are provided with the same reference numerals. Here are shown schematically:

1 a motor vehicle with a Antriebsabschaltsteuerung and

2 a schematic representation of the drive shutdown control.

1 shows a motor vehicle 2 with a drive shutdown control 4 (dashed framed).

The car 2 has an internal combustion engine 6 on, which can be switched on and off. The internal combustion engine 6 provides energy for an electric power steering 8th ready.

The steering power assistance 8th is presently designed as an electric motor, which is on a steering shaft 10 Works with a steering wheel 12 connected is.

At the steering shaft 10 is a steering angle sensor 14 provided, a position of the steering wheel 12 detected.

The steering shaft 10 acts via a steering gear 16 on a steered axle, here a front axle 18 , The front axle 18 has a left wheel 20 as well as a right wheel 22 on.

At the wheels 20 . 22 the front axle 18 are each wheel speed sensors 24 . 26 intended.

The motor 6 has a motor control 28 on, with the help of aggregates of the internal combustion engine 6 can be operated, including a starter 30 as well as an ignition 32 ,

The present embodiment is based on a gasoline engine, but is readily transferable to other engine concepts, such as diesel engines. In this case, instead of an ignition knows 32 a fuel pump can be controlled.

The drive shutdown control 4 has a controller 34 on that with the engine control 28 , the wheel speed sensors 24 . 26 and the steering angle sensor 14 connected is. The control unit 34 can use the input variables of the sensors control commands to the engine control 28 that cause the internal combustion engine 6 is turned on or that a shutdown of the engine 6 is prevented. This can be done specifically by the fact that in the case of an internal combustion engine, a starter 30 is pressed to the internal combustion engine 6 to start or switch off the ignition 32 to prevent, if the internal combustion engine is to be switched off.

In the case of a diesel engine, for example, to activate the diesel engine, a starter can be actuated and to prevent the shutdown of the diesel engine shutdown of a fuel pump can be prevented.

2 shows a schematic representation of the processing of the signals in the control unit 34 ,

A first decision criterion is the steering torque on the steering wheel 12 , This is calculated from the steering angle gradient and the wheel speeds at the front axle.

The first input variable is the steering angle gradient, which is converted into a usable variable by means of a calibration step.

Other input variables are wheel speed speeds of the left wheel 20 and the right wheel 22 , Absolute numbers are first determined here and then the minimum of the absolute values of the wheel speed velocities is determined. The value is then calibrated to a usable size.

The magnitude calculated from the wheel speed velocities is subtracted from the magnitude calculated from the steering angle gradient. When the wheels are turning, steering distortion is reduced and the steering torque is low. If the wheels do not turn or only very slowly, the tension of the steering increases and the steering torque is higher.

An integrator circuit 1 / z provides the state of the last measurement for the next measurement and thus allows an incremental view of the change in tension that is added to the difference in the subtraction step of the usable variables of steering angle gradient and wheel speed.

Further feedback takes place from integrator 1 / z into the calibration step of the wheel speed velocities by taking the sign of integration. In this way, a distinction is made as to whether the tension on the steering increases or decreases. As the front wheels rotate, the amount of tension decreases, i. H. if the tension increases, something has to be removed; if the tension is lower, something has to be added. It does not matter if the front wheels turn forwards or backwards.

From the calculation described above, an absolute value is formed, which is compared with a comparison quantity.

A second decision criterion for stopping the drive shutdown or forcing the activation of the drive 6 is the steering angle.

In a path parallel to the above-described path, therefore, an absolute value is formed from the steering angle, which is compared with another comparison quantity. If the speed-dependent steering angle gradient is greater than a Grenzlenkwinkelgradient, a shutdown of the engine 6 prevented.

In the case of a steering angle greater than a limiting steering angle is also a shutdown of the engine 6 prevented.

Should the internal combustion engine 6 If it is already switched off, switching on the internal combustion engine can occur when one of the two criteria occurs 6 via actuation of the starter 30 be effected.

Although the subject matter has been further illustrated and explained in detail by way of embodiments, the invention is not limited by the disclosed examples, and other variations can be derived therefrom by those skilled in the art. It is therefore clear that a multitude of possible variations exists. It is also to be understood that exemplary embodiments are only examples that are not to be construed in any way as limiting the scope, applicability, or configuration of the invention. Rather, the foregoing description and description of the figures enable one skilled in the art to practice the exemplary embodiments, and those of skill in the knowledge of the disclosed inventive concept may make various changes, for example, to the operation or arrangement of particular elements recited in an exemplary embodiment, without Protected area, which is defined by the claims and their legal equivalents, such as further explanation in the description.

LIST OF REFERENCE NUMBERS

2

motor vehicle

4

Antriebsabschaltsteuerung

6

internal combustion engine

8th

Power Steering

10

steering shaft

12

steering wheel

14

Steering angle sensor

16

steering gear

18

Front

20

left wheel

22

right wheel

24

left wheel speed sensor

26

right wheel speed sensor

28

motor control

30

Starter

32

ignition

34

control unit

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 9043119 B2 [0004]

Claims (4)

Drive shutdown control for a motor vehicle ( 2 ), wherein the motor vehicle ( 2 ) a drive ( 6 ) and an electric power steering ( 8th ), wherein the drive shutdown control ( 4 ) with a steering angle sensor ( 14 ), wherein the drive shutdown control ( 4 ) is adapted to calculate a steering angle gradient from at least two steering angle sensor measurements, wherein the drive shutdown control ( 4 ) is adapted to, from the steering angle gradient, a steering torque on a steering wheel ( 12 ) of the motor vehicle ( 2 ), wherein the drive shutdown control ( 4 ) is set up in a) exceeding a first limiting steering torque, a shutdown of the drive ( 6 ) and / or b) exceeding a second limiting steering torque activation of the drive ( 6 ) to force. A drive shutdown control according to claim 1, wherein the drive shutdown control ( 4 ) is set up in a) exceeding a first limiting steering angle, a shutdown of the drive ( 6 ) and / or b) exceeding a second limit steering angle activation of the drive ( 6 ) to force. A drive cutoff control according to claim 1 or 2, wherein the drive cutoff control is provided with a wheel speed sensor (10). 24 ) for a left wheel ( 20 ) and a wheel speed sensor ( 26 ) for a right wheel ( 22 ) connected is. Motor vehicle with a drive shutdown control ( 4 ) according to one of claims 1 to 3.

Images