Automatically actuated braking system

Abstract

The present invention concerns a process for externally actuating a brake system as well as a brake system suitable for this purpose. The object of the present invention is to ensure that the brake system is automatically set to a suitable actuation state on the basis of an appropriate sensor. However, any danger to the driver or accidental actuation of the brake should be prevented to as large an extent as possible. Taking this into account, the present invention proposes that both the surroundings of the brake pedal and, if necessary, additional parameters (d,{dot over (d)}, v ref ) be monitored by means of a sensor unit ( 6, 10, 11 ). Then the brake pressure (p nom ) will be set automatically in an expedient manner in dependence of the individual parameters that were evaluated. Advantageous further embodiments include proposals for precharging the brake or braking slightly or automatically applying a higher brake pressure in dependence of the measuring results, in so far as this is reasonable with respect to road conditions and the driver's wishes as they were assumed by the system.

1 . A process for actuating the brake system of a vehicle with the help of the driver's foot ( 9 ), wherein said brake system is equipped with a brake actuating element, in particular brake pedals ( 4 ), characterized in that a sensor device ( 6 , 10 ) located in the vicinity ( 7 ) of the brake pedal ( 4 ) measures the position (A, B) and/or change of position ({dot over (A)}, Ä, {dot over (B)}, {umlaut over (B)}) of the foot or the pedal and/or the force ( 11 ) exerted by the foot ( 9 ) on the brake actuating element and/or a safety value (d, {dot over (d)}, v ref ) defined on the basis of a vehicle driving in front, and an evaluation unit compares the measured state with at least one defined state and actuates the brake system depending on the result of the comparison.  
     
     
         2 . A process according to  claim 1 , characterized in that the evaluation unit compares the result of the measurement with one or several defined states and that the type of actuation of the brake system depends on the result of the comparison.  
     
     
         3 . A process according to  claim 1  or  2 , characterized in that the position (A) and/or change of position ({dot over (A)},Ä) of the foot ( 9 ) is measured above the brake actuating unit ( 4 ), in particular the brake pedal.  
     
     
         4 . A process according to one of the  claims 1  to  3 , characterized in that the position (B) and/or the change of position ({dot over (B)}, {umlaut over (B)}) of the foot ( 9 ) standing on the brake actuating unit ( 4 ) and/or the force (F) exerted by the foot on the brake actuating unit are measured.  
     
     
         5 . A process according to one of the preceding claims, characterized in that the actuation of the brake system depends on the measuring result or the measuring results during precharging, initial braking, adjustment of an appropriate brake pressure or application of the maximum brake pressure.  
     
     
         6 . A process according to one of the preceding claims, characterized in that precharging or initial braking occurs in the brake system as soon as the distance (A) between the foot and the brake actuating unit ( 4 ) falls below a first specified distance value and/or the speed of movement ({dot over (A)}) towards the pedal and/or acceleration (Ä) exceeds a corresponding specified value and/or the safety value measured (d, {dot over (d)}, v ref ) has reached a sufficiently high value.  
     
     
         7 . A process according to one of the  claims 1  to  6 , characterized in that the brake system is initially braked or brought to full brake force when the foot ( 9 ) is in contact with the brake pedal ( 4 ) and the speed of movement ({dot over (B)}) towards the floor panel ( 1 ) and/or acceleration ({umlaut over (B)}) and/or the force of the foot ( 9 ) exceeds a corresponding specified value.  
     
     
         8 . A process according to one of the preceding claims, characterized in that the brake force set in the brake system depends on the speed measured ({dot over (A)}, {dot over (B)}) and/or acceleration (Ä, {umlaut over (B)}) of the foot or the pedal ( 9 ).  
     
     
         9 . A process according to one of the preceding claims, characterized in that the braking pressure (P nom ) of the brake system is increased appropriately as a function of several values determined parallel to one another (p 1 , p 2 , p 3 ).  
     
     
         10 . A process according to  claim 9 , characterized in that certain brake pressures (p 1 , p 2 , p 3 ) are assigned to individual, generically different measured values (d, {dot over (d)}, v ref  or A, B, F) and that when these measured values occur parallel in the brake system the brake pressures are added or their maximum is formed.  
     
     
         11 . A process according to one of the preceding claims, characterized in that the safety signal (p 1 ) supplied by a second sensor device (d, {dot over (d)}, v ref ) is derived from the speed (v ref ) and/or the vehicle's own acceleration ({dot over (v)} ref ) and/or the distance (d) and/or the relative speed ({dot over (d)}) with respect to a vehicle driving in front and/or the acceleration of a vehicle driving in front ({dot over (v)} 1 ).  
     
     
         12 . A brake system with a brake actuating element, in particular a brake pedal ( 4 ), also for carrying out the processes according to  claims 1  to  11 , characterized in that at least a first sensor unit ( 6 ,  10 ) is provided to monitor the position (A, B) and/or the change in position ({dot over (A)}, {dot over (B)}) of the foot ( 9 ) located above or on the pedal, and an evaluation unit actuates the brake system on the basis of the measuring results, wherein the type and extent of actuation depends on the measuring results.  
     
     
         13 . A brake system according to  claim 12 , characterized in that a first sensor ( 6 ), preferably an infrared sensor, is assigned to the first sensor unit ( 6 ,  10 ) on the brake pedal, that the sensor preferably is mounted somewhere on the pedal surface facing away from the foot ( 9 ) and monitors the area ( 7 ) of the pedal facing towards the foot through an opening ( 5 ) in the pedal ( 4 ), that a first sensor of the sensor unit, preferably a capacitive sensor, is mounted on the surface of the pedal facing towards the foot or that a first sensor of the sensor unit, preferably an infrared sensor, is integrated in a corresponding opening in the pedal.  
     
     
         14 . A brake system according to  claim 13 , characterized in that a second sensor ( 10 ) is provided in the first sensor unit, wherein said second sensor monitors the distance (B) and/or the change in distance ({umlaut over (B)}) of the pedal with respect to a reference point.  
     
     
         15 . A brake system according to one of the  claims 12  to  14 , characterized in that a force sensor ( 11 ) is provided in the first sensor unit ( 6 ,  10 ,  11 ), which measures the force exerted on the brake pedal ( 4 ) by the foot ( 9 ).  
     
     
         16 . A brake system according to one of the  claims 12  to  15 , characterized in that an additional sensor unit (d, {dot over (d)}, v ref ) is provided to measure the speed (v ref ) of the vehicle and/or the distance (d) and/or the relative speed ({dot over (d)}) with respect to a vehicle driving in front and/or an evaluation unit to calculate the vehicle's own acceleration ({dot over (v)} ref ) and the acceleration of the vehicle driving in front ({dot over (v)} 1   ).    
     
     
         17 . A brake system according to  claim 16 , characterized in that a first arithmetic unit ( 15 ) is provided, which determines the brake pressure (p 1 ) to be actuated on the basis of a specified safety time (T), the vehicle's own speed (v ref ) and/or the vehicle's own acceleration ({dot over (v)} ref ) and/or the relative speed ({dot over (d)}) and/or the distance (d) to a vehicle driving in front and/or its acceleration ({dot over (v)} 1 ).  
     
     
         18 . A brake system according to one of the  claims 12  to  17 , characterized in that said brake system is equipped with a second arithmetic unit ( 16 ) which determines the brake pressure (p 2 ) to be actuated on the basis of the distance (A) between the foot ( 9 ) and the brake pedal ( 4 ) and/or the pedal path ( 8 ), and/or that a third arithmetic unit is provided, which determines the brake pressure (p 3 ) to be actuated on the basis of the foot force measured.  
     
     
         19 . A brake system according to  claim 18 , characterized in that a coordination unit ( 17 ) is provided, which determines an appropriate brake pressure (P nom ) based on the values output by the arithmetic units ( 15 ,  16 , p 1 , p 2 , p 3 ).  
     
     
         20 . A brake system according to one of the  claims 12  to  15 , characterized in that a brake pressure transducer ( 20 ) which can be actuated independently of the foot's actions, preferably a booster, is provided, wherein said brake pressure transducer supplies the brake pressure that is to be applied in accordance with the output signals of the coordinator ( 17 ) and/or the arithmetic units and/or the evaluation unit.