Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
  • B60T13/74—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with electrical assistance or drive
  • B60T13/741—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with electrical assistance or drive acting on an ultimate actuator
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T7/00—Brake-action initiating means
  • B60T7/02—Brake-action initiating means for personal initiation
  • B60T7/04—Brake-action initiating means for personal initiation foot actuated
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T7/00—Brake-action initiating means
  • B60T7/12—Brake-action initiating means for automatic initiation; for initiation not subject to will of driver or passenger
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D55/00—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes
  • F16D55/02—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes with axially-movable discs or pads pressed against axially-located rotating members
  • F16D55/22—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes with axially-movable discs or pads pressed against axially-located rotating members by clamping an axially-located rotating disc between movable braking members, e.g. movable brake discs or brake pads
  • F16D55/224—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes with axially-movable discs or pads pressed against axially-located rotating members by clamping an axially-located rotating disc between movable braking members, e.g. movable brake discs or brake pads with a common actuating member for the braking members
  • F16D55/225—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes with axially-movable discs or pads pressed against axially-located rotating members by clamping an axially-located rotating disc between movable braking members, e.g. movable brake discs or brake pads with a common actuating member for the braking members the braking members being brake pads
  • F16D55/226—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes with axially-movable discs or pads pressed against axially-located rotating members by clamping an axially-located rotating disc between movable braking members, e.g. movable brake discs or brake pads with a common actuating member for the braking members the braking members being brake pads in which the common actuating member is moved axially, e.g. floating caliper disc brakes
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D65/00—Parts or details
  • F16D65/14—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position
  • F16D65/16—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position arranged in or on the brake
  • F16D65/18—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position arranged in or on the brake adapted for drawing members together, e.g. for disc brakes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T1/00—Arrangements of braking elements, i.e. of those parts where braking effect occurs specially for vehicles
  • B60T1/02—Arrangements of braking elements, i.e. of those parts where braking effect occurs specially for vehicles acting by retarding wheels
  • B60T1/06—Arrangements of braking elements, i.e. of those parts where braking effect occurs specially for vehicles acting by retarding wheels acting otherwise than on tread, e.g. employing rim, drum, disc, or transmission or on double wheels
  • B60T1/065—Arrangements of braking elements, i.e. of those parts where braking effect occurs specially for vehicles acting by retarding wheels acting otherwise than on tread, e.g. employing rim, drum, disc, or transmission or on double wheels employing disc
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
  • B60T13/74—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with electrical assistance or drive
  • B60T13/746—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with electrical assistance or drive and mechanical transmission of the braking action
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D2121/00—Type of actuator operation force
  • F16D2121/02—Fluid pressure
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D2121/00—Type of actuator operation force
  • F16D2121/14—Mechanical
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D2125/00—Components of actuators
  • F16D2125/18—Mechanical mechanisms
  • F16D2125/20—Mechanical mechanisms converting rotation to linear movement or vice versa
  • F16D2125/34—Mechanical mechanisms converting rotation to linear movement or vice versa acting in the direction of the axis of rotation
  • F16D2125/40—Screw-and-nut

Definitions

• Braking device for a motor vehicle and method for controlling the braking device
• the present invention relates to a method for controlling a parking brake device, wherein the parking brake is adjusted by means of a sensitive control to the requirements of the respective operating situation.
• DE102011004772A1 is known from the prior art.
• a method for adjusting the force exerted by a parking brake clamping force is generated, which is at least partially generated by an electromechanical braking device with an electric brake motor.
• the mechanical work generated by the actuator is determined and the application process is carried out until the mechanical work produced reaches a threshold value.
• Electrical parameters are used to determine the electrical work, in particular the current and the voltage of the electric brake motor, which are preferably determined directly or indirectly by sensors and present as measured values.
• DE102004021534A1 is known.
• This document relates to a method for an automated parking brake operation in a motor vehicle leading to the locking of an automated parking brake.
• the essence of this prior art is that the implementation of the automated parking brake operation can be carried out in a normal operation and a test operation, wherein the normal operation and the test operation at least by the speed of performing the
• the braking force is first constructed by a hydraulic wheel pressure and then a transfer of hydraulically constructed braking force to a mechanical brake force holding device.
• This prior art discloses that parallel to the transfer or after the transfer of the hydraulic pressure is reduced again and in the locked state of the parking brake, the braking force is applied regardless of the presence of hydraulic pressure from the mechanical brake force holding device, the size of the hydraulic brake force of the duration of an uninterrupted actuation of the control element depends.
• the clamping force For a determination and adjustment of a clamping force of a parking brake, the clamping force, eg. By means of the work done estimated. From a defined threshold, the control is switched off accordingly.
• the minimum clamping force which can be reliably detected in this case is relatively high, since the error rate is lower at higher currents. Disturbances are therefore less at higher currents, but at lower currents more significant.
• a variety of operating situations still requires a small first power level. Also, specific operating situations do not allow a quick build-up of a parking force of the parking brake. In the prior art, therefore, bpsw. the clamping force structure made by means of the hydraulic brake.
• Parking brake operation in a motor vehicle with an automated parking brake wherein the parking brake operation has at least two phases, wherein in a first upstream phase no clamping force is established by the parking brake, and in a second downstream phase, a clamping force is established by the parking brake, wherein the parking brake is a controllable Feststellbremsaktuator for generating the clamping force has characterized in that a control of the
• Parking brake actuator is modified in a detection of a transition from the first phase to the second phase.
• the behavior of the parking brake can be modified.
• the application speed can be changed, in particular reduced.
• a modification may also lie in interrupting the parking brake operation. This may be a temporary interruption.
• a timely shutdown of the actuator allows and unnecessary brake application, in particular unnecessary and / or unwanted braking force, can be avoided.
• a further force build-up can essentially be avoided, for example, by means of a short circuit of the parking brake actuator.
• the modification relates to a regular performance of the parking brake operation in the second phase.
• a modification takes place upon detection of a transition from the first phase to the second phase.
• Essential here is the actual transition.
• the modification takes place immediately after the detection of the phase transition. This is understood to mean that the control is modified substantially immediately after the detection.
• Under control is understood to mean the currently present actual control, in particular current and voltage, as well as the process of the control, in particular the change in the current and voltage over time.
• a modification of the parking brake operation in the transition region between the first and second phase can also take place.
• the parking brake operation is performed in a detection of a transition not in the second phase, but is continued at the detected phase transition, that is, in the boundary region between the first and second phase.
• a modification of the parking brake operation may be made in reference to the first phase.
• the parking brake operation, or the parking brake are returned to the area of the first phase and, for example, be stopped there.
• the actuator is so - in particular inverted - driven to move the components of the parking brake so that the parking brake operation is again in the first phase.
• the method is characterized in that the detection of the transition from the first phase to the second phase takes place on the basis of a time profile of a specific parameter of the actuation of the parking brake actuator.
• the measurement times have an equidistant time interval from one another.
• the measurements take place, for example, every 5 milliseconds. Alternatively, other measurement times can be defined.
• a time characteristic of the parameter is the development of the parameter values over time.
• a transition is identified if the curve has, for example, a correspondingly defined pattern and / or the parameter values have a specific relation to one another.
• the method according to the invention is suitable for starting the second phase in a robust manner, i. essentially error-free, to identify.
• the detection continues to be as close as possible to the time transition point, i. in a very short time - in relation to the detection process - after an actual transition from the first phase to the second phase.
• the method is in a further advantageous embodiment, characterized in that a transition from the first to the second phase is detected when a steady increase in the clamping force is detected, with a steady increase in clamping force is detected when several, especially four, rising temporally directly consecutive current values as specific
• Parameters of a control of the parking brake actuator can be determined.
• Transition of the first phase to the second phase by means of an evaluation of the neighborhood relationships between the digitally measured data points of the motor current takes place.
• the motor current allows for estimation and / or calculation of the present clamping force, therefore the current values are selected as specific parameters of a drive.
• a transition from the first phase to a second phase is then identified when a steady increase in clamping force is detected.
• a steady increase in clamping force is considered safe, i. the estimation as robust, if the stream at several,
• this transition can advantageously be recognized within a period of 20 milliseconds after the transition from the first phase to the second phase.
• the method is characterized in a further advantageous embodiment, characterized in that a transition from the first to the second phase is detected when a steady and sufficient increase in the clamping force is detected, with a sufficient increase in the clamping force is then detected when several, in particular 3 , increasing difference amounts - the temporally directly consecutive current values of an activation of the
• Feststellbremsaktuators - be determined, or if several, in particular 3, difference amounts - the time directly consecutive current values of a control of Feststellbremsaktuators - each one above the
• Difference amount associated threshold where the thresholds are the same or there is a steady increase in the thresholds corresponding to the time rank of the associated difference amounts.
• a sufficient increase is detected when a plurality, in particular 3, of difference amounts-the temporally directly consecutive current values of an actuation of the parking brake actuator-each lie above a threshold value assigned to the difference amount Threshold values are equal or there is a steady increase in the threshold values corresponding to the time rank of the assigned difference amounts.
• Typical values for the thresholds a, b, c are:
• a a, b, c 0.3 to 1
• a a, b, c are here to be understood as threshold values which correspond to the existing
• Brake system or the respective component behavior can be adjusted.
• the following relationship applies when choosing the parameters: the smaller the values of a, b, c, the more sensitive the detection; the smaller the values of a, b, c, the more susceptible is the detection of interference.
• the method is characterized in that current values of a switch-on peak are not taken into account in an evaluation of the current values for detecting the clamping force increase, wherein in particular a non-consideration of current values of a switch-on peak is made possible by means of a time factor, in particular that none Consideration of current values of the first 10ms of the
• the switch-on peak has high current values for a short time. However, in order not to erroneously conclude on a clamping force, these values can be excluded in the analysis. For example. Current values above a certain level indicate a switch-on peak and can not be taken into account accordingly from this current value level. Since the switch-on peak occurs during the switch-on, it is also possible the
• Operating situation can be identified by stored profiles or parameters.
• the operating situations include: chassis dynamometer, recalibration, incremental forcelevel application (IFA), rear wheel unlocker (RWU), piloted parking and brake wiper.
• IFA incremental forcelevel application
• RWU rear wheel unlocker
• piloted parking and brake wiper piloted parking and brake wiper.
• the parking brakes are tested. This is done in most cases by means of a chassis dynamometer.
• the chassis dynamometer measures an opposing force that can be built up by the brake.
• the clamping force must not be built arbitrarily fast.
• Park brakes in Motor on Caliper (MoC) design have a very high power output dynamics. This can lead to incorrect measurements in the functional test of the
• Vehicle movement can follow the forces defined on the chassis dynamometer.
• Vehicle is prematurely pushed out of the chassis dynamometer and the measurement is not completed.
• the recalibration is a
• Parking brake to understand By means of the procedure, such can be carried out without significant force build-up.
• the advantage here is that - when in a performance of the recalibration of the driver accelerates the vehicle - overbraking the rear axle is substantially avoided. Safety on the vehicle level is thus significantly increased.
• Parking brake button in the direction close pressed The challenge in this case is that this function may occur while driving (only as a fallback if there is no vehicle speed).
• Identification of the transition of the first to the second phase is advantageous since any further activation leads to a buildup of force. Furthermore, the initial clamping force level in this case is so low that even with unfavorable coefficients of friction (leaves, snow), a blocked rear axle can not immediately occur.
• the clamping force is increased until a defined slip is achieved between the wheels of the front axle and the wheels of the rear axle. If the slippage increases - eg due to snow, rain, leaves, etc. - the clamping force is reduced until the slippage falls below a defined value again. Subsequently, the clamping force is increased again.
• a first target clamping force alternatively, a desired deceleration can also be entered. Depending on whether the set deceleration or the slip value is reached first, the clamping force is not further increased.
• we have the advantage that the initial clamping force stage is very small. The clamping force can now be carefully increased during the control (even in very small steps) and the reaction of the wheel can be considered. Because the Steps are much smaller than conventional, can also be regulated accordingly more sensitive.
• piloted parking allows the vehicle, for example, an independent parking.
• the procedure is suitable as fallback, since the free travel of the parking brake is minimized during piloted parking.
• the clamping force increase can be detected and the parking brake actuator e.g. be triggered for a defined time of 20 milliseconds towards loosening.
• the small clamping force level is thus reduced again. Should it now come in this function to a degradation, the parking brake can immediately provide a clamping force without having to go through large free paths.
• a covering in particular water, is wiped off the brake disk by means of the parking brake.
• the applied clamping force can be kept minimal and not noticeable to the driver by the procedure.
• the method is characterized in that an existing force level is maintained for a defined time, in particular in the range of 0.5 to 5 seconds, and the parking brake operation is subsequently carried out further.
• the parking brake operation in particular in the second phase, is interrupted.
• this time can be used to check specific reactions of the vehicle and then adapt the further course of action.
• after the interruption of the parking brake operation can be carried out further.
• the time of interruption is advantageously about 0.5 seconds.
• the time interval can extend up to 5 seconds.
• the duration of the defined time interval can be defined as adapted to the present operating situation.
• differences between first and further interruptions in the same operating situation may prove advantageous.
• a further force build-up by the actuator by means of a short circuit can be substantially avoided.
• the motor is braked relatively hard by the self-induction; the further increase in force is greatly minimized.
• the engine may simply be turned off when the force increase is detected. In this case, however, the engine will roll out due to the moment of inertia for some time and continue to build up some power. However, it is not necessary to generate a short circuit.
• the motor may also be briefly energized inverted in the short circuit instead of a short circuit.
• the engine is braked even more or may turn it. even back in the opposite direction. A possible build-up of strength is neutralized with it again.
• the actuator can, for example, be energized inverted when detected force increase for a defined time, for example. 5 milliseconds.
• the method is characterized in that a plurality of force levels of the clamping force are set in a course of the second phase.
• This force level can be defined absolutely and, if necessary, approached by means of a force estimation based on an evaluation of the current values of the control. Alternatively, the force level can also be set on the basis of an evaluation of a clamping time or a Zuspannwegs.
• another force level is defined in relation to a previous force level. This means that starting from a current force level, another force level is approached. It may also be advantageous to achieve a minimal but robust level increase. Suitable for this purpose a repetition of the procedure already described. As a result, a clamping force build-up can take place in small power stages.
• Force levels - for example, the first three force levels - may also differ from the method for setting the other - in particular later to be adjusted - force levels.
• Force levels - may also differ from the method for setting the other - in particular later to be adjusted - force levels.
• Clamping force gradient is set.
• Clamping force gradient is in relation to a Klemmkraftgradienten a second phase of a regular parking brake operation.
• the Klemmkraftgradient describes the clamping force increase over time. By reducing a slower power build-up. This is advantageously realized by a reduced travel speed of the actuator.
• several clamping force levels can be approached, wherein the interruption must be kept no defined period of time. For example. can at a detection a force increase of the actuator are turned off. Furthermore, the actuator is promptly activated again when the standstill is reached.
• the method is in a further advantageous embodiment, characterized in that the parking brake is brought into a defined, in particular substantially open, starting position, and in particular an entry of information about the transition from the first phase to the second phase in a memory for recalibration ,
• the parking brake is actuated to close by means of the modified activation of the parking brake actuator.
• the procedure identifies the transition from the first phase to the second phase and places it in a memory. From this, the information necessary for recalibration can be obtained. Subsequently, the parking brake is actuated back to an opened starting position. Furthermore, reference is made to the comments on the operating situation recalibration.
• the method is characterized in that the parking brake is opened in such a way that a clamping force generated in the second phase is reduced and a clearance of the first phase essentially remains overcome.
• the parking brake is actuated to close by means of the modified activation of the parking brake actuator.
• the process identifies the transition from the first phase to the second phase.
• the parking brake is then not driven in the direction of closing, but for a short time in the direction of opening, in order to reduce the built-up clamping force, or reduce. Furthermore, reference is made to the comments on the operating situation piloted parking.
• a parking brake operation has at least two phases, wherein in a first upstream phase no clamping force by the Parking brake is constructed, and in a second subsequent phase, a clamping force is established by the parking brake, and wherein the
• Parking brake has a controllable Feststellbremsaktuator for generating the clamping force, characterized in that the control device comprises means by means of a transition from the first phase to the second phase based on a time course of a specific parameter
• Arithmetic unit is provided for the motor vehicle, which is configured, that is set up and / or has means to perform a - as described above - process or support.
• a parking brake operation has at least two phases, wherein in a first upstream phase no clamping force is established by the parking brake, and in a second downstream phase, a clamping force is established by the parking brake, and wherein the
• Parking brake has a controllable parking brake actuator for generating the clamping force, characterized in that the parking brake is adapted to a transition from the first phase to the second phase based on a time course of a specific parameter
• a parking brake is provided for the motor vehicle which is configured, that is to say is set up and / or has means, to carry out or to support a method as described above.
• Fig. 1 as a prior art, a schematic sectional view of a
• FIG. 5 shows an idealized course of a motor current over time during generation of a clamping force as well as the neighborhood relationships of FIG
• Fig. 6 shows a course of motor current and clamping force and a
• Fig. 7 shows a course of motor current and clamping force and a
• Fig. 8 is a flowchart of a functional test of a parking brake in the context of a vehicle main inspection.
• Fig. 1 shows a schematic sectional view of a braking device 1 for a vehicle according to the prior art.
• the braking device 1 in this case has an automated (automatic) parking brake (parking brake), which can exert a clamping force for setting the vehicle by means of an actuator 2 (brake motor), which is designed here as a DC motor.
• the actuator 2 of the parking brake drives a spindle 3, in particular a threaded spindle 3, mounted in an axial direction.
• the spindle 3 is provided with a spindle nut 4, which rests against the brake piston 5 in the applied state of the automated parking brake.
• the parking brake transmits in this way electromechanically a force on the brake pads 8, 8 ', and the brake disc (7).
• the spindle nut rests against an inner end face of the brake piston 5.
• the spindle nut 4 and the brake piston 5 are mounted in a caliper 6, which engages over a brake disc 7 like a pincers.
• the automated parking brake is embodied, for example, as a "motor on caliper" system and combined with or integrated into the service brake, however, the service brake has a separate actuator 10.
• the service brake is designed as a hydraulic system in FIG. wherein the actuator 10 is represented by the ESP pump 10. To build up a braking force by means of the hydraulic service brake, a medium 11 is pressed into a fluid space bounded by the brake piston 5 and the brake caliper 6. The brake piston 5 is sealed from the environment by means of a piston sealing ring 12 ,
• control unit 9 which may, for example, be a control unit of a vehicle dynamics system such as ESP (electronic stability program) or another control unit.
• ESP electronic stability program
• Brake disc 7 referred to in disc brake systems of motor vehicles. This process usually takes a relatively long time with regard to the overall control, in particular in the case of the automated parking brake. At the end of such a preparation phase, the brake pads 8, 8 'to the brake disc 7 created and the force builds up in another control.
• Fig. 1 shows the state of the already overcome Leerweg and clearance.
• the brake pads 8, 8 'applied to the brake disc 7 and all brakes, ie the parking brake and the service brake can immediately build a braking force to the corresponding wheel in a subsequent control.
• FIG. 2 shows an exemplary motor current profile I as well as
• Park brake that is the spindle nut which is driven via the spindle by means of the actuator of the automated parking brake is activated or deflected.
• the two times t1 and t2 mark the start and end time of the phase PI.
• the X-axis represents a time track. From the times of the X-axis, for example, deflection positions of the parking brake actuator can be derived.
• the time tl corresponds for example to the rest position of the parking brake and the parking brake actuator.
• the idle travel (the parking brake actuator) and the clearance
• the two times t3 and t4 mark the starting point and the end point of the phase P3.
• the times t3, or t4 represent exemplary another operating state of the parking brake.
• Fig. 3 shows the behavior of the components when switching off the actuator of the parking brake. At time t31, the current I is turned off. As a result, an angular velocity w of the actuator 2, too
• each additional path for example, even when the actuator of the automatic parking brake runs out, leads directly to a further force build-up. If a further power build-up is not desired, the actuator of the parking brake must be braked immediately after a shutdown. This can eg by means of a short circuit of the motor terminals by the
• Control electronics are implemented.
• FIG. 5 shows a current profile I over the time t, such as is present, for example, in the context of the force build-up phase P3.
• the current flow is illustrated schematically idealized.
• the measuring points k-3, k-2, k-1, k are shown here.
• the measurement of the digital data points takes place in each case with an equidistant time interval T A between the measuring points.
• Fig. 5 illustrates the difference d of the current values I, which is present between two adjacent measuring points. For this purpose, the current value differences dl, d2, d3 are shown.
• FIG. 6 shows a progression of motor current I and clamping force F k i e mm over time with an initial increase in force. Furthermore, an identified increase in force of the clamping force is shown schematically and by way of example.
• the tip of the curve F An marks the time at which the force increase of the clamping force has been identified. Here, a sampling time of 5 milliseconds was chosen.
• the condition 1 was set for a steady clamping force increase, which is considered fulfilled if 4 measured values have an increasing current value. A consideration of current values takes place, for example, up to 5 amperes. At higher current values one starts from a connection peak.
• FIG. 6 shows that during the switch-on peak, the measured current values exceed the defined limit and are therefore not taken into account.
• the first 10 milliseconds of the switch-on process can not be evaluated in order to exclude an initial current peak from the evaluation.
• the current is almost constant. In this case, no four consecutive rising current values are measured, which indicate a clamping force increase. Only when the actual clamping force increase is reached is the criterion fulfilled after four measured and increasing current values. Detection is possible already after 20 milliseconds after the actual increase due to the sampling time and condition.
• FIG. 7 shows a progression of motor current I and clamping force F k i e mm as well as an identified force increase of the clamping force over time at a further force stage.
• the identified increase in force is again illustrated by means of a curve F An .
• FIG. 7 shows the identification of a clamping force increase at a further power stage, for example a second power stage after an already performed first interruption.
• Fig. 7 shows that an increase in successive current values can also be used at an increase in force after the first clamping force stage and at each other.
• Klemmkraftmaker N and the clamping force level N + l turn out to be very low.
• the same conditions four consecutive increasing current values
• Measuring points are sketched in FIG. 7. Here, a sampling time of 5 milliseconds was also chosen.
• Fig. 8 shows a flow chart for the functional test of an automated parking brake in the context of the main vehicle inspection.
• step Sl Functional test of the parking brake starts with the step Sl. This can be done by a permanent actuation of the parking brake button done.
• step S2 the actuator is driven in the closing direction.
• S31 asks whether an increase in force is detected. If it is answered in the negative (N), the flowchart returns to step S2. If affirmative (Y), the flowchart advances to step S4.
• the second decision S32 asks if the tester has canceled. If it is answered in the negative (N), the flowchart returns to step S2. If affirmative (Y), the flowchart proceeds to step S52.
• step S4 the power stage is held for a defined time interval. This is followed by three decision steps S51, S52, S53. The first decision steps S51, S52, S53.
• Step S51 asks whether the defined time interval has already passed. If it is answered in the negative (N), the flowchart returns to step S4. If affirmative (Y), the flowchart returns to step S2. The second decision step S52 asks whether the maximum force has been reached. If it is answered in the negative (N), the flowchart returns to step S4. If affirmative (Y), the flowchart proceeds to step S61. The step
• step S53 queries whether an abort has occurred by the tester. If it is answered in the negative (N), the flowchart returns to step S4. If yes (Y), the flowchart goes to step
• Step S62 represents an end of the functional test

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Transportation (AREA)
• Regulating Braking Force (AREA)
• Braking Systems And Boosters (AREA)

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• 2014
  • 2014-10-07 DE DE102014220252.3A patent/DE102014220252A1/de active Pending
• 2015
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  • 2015-08-10 EP EP15750391.3A patent/EP3204269A1/de not_active Withdrawn
  • 2015-08-10 WO PCT/EP2015/068372 patent/WO2016055194A1/de active Application Filing
  • 2015-08-10 CN CN201580054418.3A patent/CN106794825B/zh active Active

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