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
  • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
  • B60T8/32—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration
  • B60T8/34—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration having a fluid pressure regulator responsive to a speed condition
  • B60T8/40—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration having a fluid pressure regulator responsive to a speed condition comprising an additional fluid circuit including fluid pressurising means for modifying the pressure of the braking fluid, e.g. including wheel driven pumps for detecting a speed condition, or pumps which are controlled by means independent of the braking system
  • B60T8/4072—Systems in which a driver input signal is used as a control signal for the additional fluid circuit which is normally used for braking
• • 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
  • B60T7/042—Brake-action initiating means for personal initiation foot actuated by electrical means, e.g. using travel or force sensors
• • 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
  • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
  • B60T8/32—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration
  • B60T8/34—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration having a fluid pressure regulator responsive to a speed condition
  • B60T8/48—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration having a fluid pressure regulator responsive to a speed condition connecting the brake actuator to an alternative or additional source of fluid pressure, e.g. traction control systems
  • B60T8/4809—Traction control, stability control, using both the wheel brakes and other automatic braking systems
  • B60T8/4827—Traction control, stability control, using both the wheel brakes and other automatic braking systems in hydraulic brake systems
  • B60T8/4863—Traction control, stability control, using both the wheel brakes and other automatic braking systems in hydraulic brake systems closed systems
  • B60T8/4872—Traction control, stability control, using both the wheel brakes and other automatic braking systems in hydraulic brake systems closed systems pump-back systems
• • 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
  • B60T2201/00—Particular use of vehicle brake systems; Special systems using also the brakes; Special software modules within the brake system controller
  • B60T2201/02—Active or adaptive cruise control system; Distance control
• • 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
  • B60T2220/00—Monitoring, detecting driver behaviour; Signalling thereof; Counteracting thereof
  • B60T2220/04—Pedal travel sensor, stroke sensor; Sensing brake request

Definitions

• the invention relates to a method for controlling an electronically slip-controllable vehicle brake system according to the generic features of claim 1.
• Electronically slip-controllable vehicle brake systems are state of the art.
• Known vehicle brake systems are able to decelerate individual wheels of a vehicle regardless of the driver's request, for example, to spend a vehicle in a stable driving condition (Electronic
• Stability control to eliminate slip on the drive wheels (traction control system ASR) or to perform an adaptive speed or distance control to a preceding vehicle (Automatic cruise control; ACC).
• ASR traction control system
• ACC Automatic cruise control
• an electronically slip-controllable vehicle brake system comprises a driver operable by foot pedal 12 brake booster 10 with a downstream master cylinder 14.
• two identically constructed hydraulic brake circuits 16, 18 are connected to the master cylinder 14.
• Each brake circuit 16, 18 serves to actuate two wheel brakes 20, 22; 24, 26.
• a modulation of the prevailing in these wheel brakes 20 - 26 brake pressure is possible by means of solenoid valves, which are controlled by an electronic control unit 28.
• the outlet of the pressure reduction valves of a brake circuit 16, 18 opens into a common return line 34.
• a pressure medium reservoir 36 is connected to this return line 34.
• the return line 34 leads to the suction side of a pressure generator 38 which is actuated by a controllable drive motor 39 and pressure medium under increased pressure to the pressure build-up valves 30 of the wheel brakes 20 - 26 and promotes the master cylinder 14.
• the suction side of the pressure generator 38 is further connected to a suction line 40.
• the latter connects the pressure generator 38 to the master brake cylinder 14 in the event that the pressure medium volume provided by the pressure medium reservoir 36 should not be sufficient for a required brake pressure build-up.
• the suction line 40 is controlled by a so-called high-pressure switching valve 42.
• each brake circuit 16, 18 equipped with a so-called switching valve 44. This is connected between the master cylinder 14 and the pressure build-up valve 30 and serves to hydraulically decouple the master cylinder 14 of the wheel brakes 20 - 26 in the case of an automatic braking operation.
• the solenoid valves occupy their basic positions shown in Figure 1 in electronically controlled state.
• the high-pressure switching valve 42 and the pressure reduction valves 32 of a brake circuit 16, 18 are then in one
• the pressure build-up valve 30 of the brake circuit 16, 18 of the wheel in question is controlled by the electronic control unit 28 and switched to its blocking position.
• the pressure reduction valve 32 is in his Open position spent and the drive motor 39 of the pressure generator 38 driven.
• Pressure fluid from the affected wheel brake 20 - 26 can thereby flow into the hitherto empty accumulator 36 in and be cached therein.
• pressure medium is sucked out of this accumulator 36 by the pressure generator 38.
• Pressure reduction in the wheel brake 20 - 26 takes place until the blocked wheel again receives a rotational movement. This can be determined by means of wheel speed sensors (not shown), which supply their measuring signals to the electronic control unit 28.
• the extracted pressure medium is compressed by the pressure generator 38 and the closed pressure build-up valves 30 of a brake circuit 16, 18 upstream or promoted back into the master cylinder 14. It is thus available for a subsequent brake pressure increase again.
• the described vehicle brake system is able to automatically, d. H. regardless of the driver's request and thus regardless of an operation of the foot pedal 12 to make a braking operation.
• the switching valve 44 is switched by the electronic control unit 44 in the blocking position and thus the existing hydraulic connection of the master cylinder 14 with the wheel brakes 20, 22; 24, 26 interrupted.
• the construction of the brake pressure is effected solely by a control of the drive motor 39 of the pressure generator 38. If the driver during such an automatic braking operation, the foot pedal 12 in addition, for example, because he wants to build a higher brake pressure than specified by the system, the driver takes disadvantageous way a compared to the normal service brake operation changed pedaling characteristic (force / displacement characteristic) true. The driver feels a harder, more relentless pedal than with normal service braking because of the already established by the pressure generator 38 brake pressure in the vehicle brake system in conjunction with the held in the locked position
• This object is achieved by an invention according to the features of claim 1.
• Vehicle brake system at least approximately the same
• Vehicle brake system requires additional hydraulic components.
• FIG. 1 shows the hydraulic circuit diagram already explained at the beginning of FIG
• FIG. 2 shows the same vehicle brake system during an automatic brake operation, with foot pedal 12 actuated simultaneously
• FIG. 3 shows a flow diagram for illustrating the actuation method according to the invention.
• the vehicle brake system according to FIG. 2 is located in FIG.
• This operating state is characterized inter alia by the fact that the switching valve 44 is controlled by the electronic control unit 28 and switched to its blocking position.
• the switching valve 44 thus interrupts a hydraulic connection between the wheel brakes 20 - 26 of a brake circuit 16, 18 and the master cylinder 14.
• the high-pressure switching valve 40 is also controlled by the control unit 28 and assumes its passage position.
• the suction side of the pressure generator 38 is thus hydraulically connected to the master cylinder 14, so that the likewise controlled pressure generator 38 can suck additional pressure fluid from the master cylinder 14 and compress it to produce brake pressure.
• the pressure side of the pressure generator 38 is connected to the wheel brakes 20-26 of the brake circuit 16, 18 via the open pressure buildup valves 30 located in their basic position, while the pressure lowering valves 32 are initially closed in order to allow a brake pressure buildup.
• the pressure fluid reservoir 36 is no Pressure medium available; a connection of the accumulator 36 with the wheel brakes 20 - 26 is not due to the blocking pressure reduction valves 32.
• the foot pedal 12 is not operated by the driver; the upcoming brake pressure is generated solely by the actuated pressure generator 38.
• the first step 50 of the method according to the invention according to FIG. 3 is to determine the automatic braking operation of the vehicle brake system on the basis of the above-explained electronic control signals of the respective components.
• this actuation of the foot pedal 12 for example by means of a pressure sensor 46 which in at least one of the brake circuits 16, 18 between the master cylinder
• the pressure sensor 46 registered due to the operation of the foot pedal 12, a pressure increase in this part of the brake circuit 16, 18.
• Output signal of the sensor 46 used which is proportional to a desired vehicle deceleration by the driver, is supplied to the electronic control unit 28 and evaluated there (step 52).
• step 54 pressure fluid flows from the wheel brake 20 - 26, which is under applied brake pressure, to the accumulator 36.
• the drive signal for the drive motor 39 of the pressure generator 38 is calculated by the electronic control unit 28 such that the resulting vehicle deceleration from the maximum value of the Vehicle deceleration corresponding to the operation of the master cylinder 14 or before the operation of the master cylinder 14 prevailing vehicle deceleration corresponds (step 58).
• the brake circuit 16, 18 which is under brake pressure is the hydraulic one
• Capacity of the accumulator 36 is switched on.
• the effluent in the pressure fluid accumulator 36 pressure medium is compensated by the operation of the pressure generator 38.
• an actuation path for the foot pedal 12 is effected.
• pressure reduction valves 32 can be used, which are designed as proportional valves and accordingly between their blocking position and their passage position can be spent by the electronic control unit 28 in any number of intermediate positions in which they flow of different sizes
• more cost-effective pressure reducing valves 32 are used, which are designed as conventional switching valves and can be actuated in a clocked manner.
• the desired pedal actuation characteristic can be varied by the electronic control unit 28 via the clock frequency and the opening duration of these pressure reduction valves 32.
• the brake pressures at the wheel brakes 20, 26 of the rear axle especially during an adaptive speed and
• ACC are very low and on the other hand via the pressure generator 38 a pressure medium volume is promoted, which leads to the wheel brakes 22, 24 of the front axle to a brake pressure build-up, no effect on the total vehicle deceleration of the vehicle for the driver is noticeable.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Regulating Braking Force (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=40912034

Family Applications (1)

Country Status (7)

Families Citing this family (10)

Citations (2)

Family Cites Families (14)

• 2008
  • 2008-03-28 DE DE102008000873.7A patent/DE102008000873B4/de active Active
• 2009
  • 2009-01-27 US US12/935,194 patent/US8510009B2/en active Active
  • 2009-01-27 CN CN200980119072.5A patent/CN102046438B/zh active Active
  • 2009-01-27 EP EP09725894A patent/EP2265479A1/de not_active Withdrawn
  • 2009-01-27 WO PCT/EP2009/050882 patent/WO2009118208A1/de active Application Filing
  • 2009-01-27 KR KR1020107021560A patent/KR20100134617A/ko not_active Application Discontinuation
  • 2009-01-27 JP JP2011501158A patent/JP2011515271A/ja active Pending

Patent Citations (2)

Non-Patent Citations (1)

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