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
  • B60T8/321—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 deceleration
  • B60T8/3255—Systems in which the braking action is dependent on brake pedal data
  • B60T8/326—Hydraulic 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
  • 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
  • B60T13/745—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 a hydraulic system, e.g. a master cylinder
• • 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
  • B60T8/36—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 including a pilot valve responding to an electromagnetic force
  • B60T8/3615—Electromagnetic valves specially adapted for anti-lock brake and traction control systems
  • B60T8/3655—Continuously controlled electromagnetic valves
• • 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
  • B60T8/404—Control of the pump unit
  • B60T8/4059—Control of the pump unit involving the rate of delivery
• • 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
  • B60T8/44—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 co-operating with a power-assist booster means associated with a master cylinder for controlling the release and reapplication of brake pressure through an interaction with the power assist device, i.e. open systems
  • B60T8/445—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 co-operating with a power-assist booster means associated with a master cylinder for controlling the release and reapplication of brake pressure through an interaction with the power assist device, i.e. open systems replenishing the released brake fluid volume into the brake piping
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S303/00—Fluid-pressure and analogous brake systems
  • Y10S303/02—Brake control by pressure comparison
  • Y10S303/03—Electrical pressure sensor
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S303/00—Fluid-pressure and analogous brake systems
  • Y10S303/02—Brake control by pressure comparison
  • Y10S303/03—Electrical pressure sensor
  • Y10S303/04—Pressure signal used in electrical speed controlled braking circuit

Definitions

• the invention relates to an actuating unit according to the preamble of patent claim 1.
• Such an actuation unit for a wheel brake of a motor vehicle is already known (DE 195 27 936 AI), in which an electric motor which can be varied in speed drives a gear pump which releases pressure medium from a
• the actuating unit according to the invention with the features of claim 1 has the advantage that, on the one hand, in cooperation with the pump and the Pressure medium backflow to the pump-adjusting element, the pressure in the cylinder-piston unit and the gradient for pressure build-up and pressure reduction can be controlled, but on the other hand slip-dependent modulation of the pressure by means of the pressure build-up valve and the pressure reduction valve is possible with high dynamics.
• An embodiment of the invention is shown in simplified form in the drawing as a circuit diagram of an actuation unit for a wheel brake of a motor vehicle and is explained in more detail in the following description.
• a motor vehicle not shown in the drawing, is equipped on its wheels with an actuating unit 1 for a wheel brake 2.
• the actuating unit 1 shown as a circuit diagram has a cylinder-piston unit 3, in the cylinder 4 of which a piston 5 with a piston rod 6 is guided.
• the piston rod 6 acts on at least one brake pad 7, which can be pressed against a friction element 8 connected to a vehicle wheel, in the case of a disc brake a brake disc, and can be lifted off the latter.
• the actuating unit 1 includes a hydraulic pump 12 which can be driven by an electric motor 11 and which is variable in speed.
• the pump is on its pressure side 13 through a first line 14 with a brake lining facing away from the brake pad Cylinder chamber 15 of the cylinder-piston unit 3 in a fluid-conducting connection.
• a second line 17 leading to the suction side 16 of the pump 12 extends from the first line 14.
• a pressure build-up valve 18 designed as a 2/2-way valve is arranged in the first line 14 between the connection of the second line 17 and the pressure side 13 of the pump 12.
• the pressure build-up valve 18 is spring-actuated in its open position; Electromagnetically operated, it can be switched to its locked position.
• the pressure build-up valve 18 is bypassed by a bypass line 19, in which a check valve 20 with a blocking effect from the pump 12 to the cylinder chamber 15 is provided.
• a pressure relief valve 21 which is also designed as a 2/2-way valve and which, when actuated by spring, assumes its blocking position and by electromagnetism, in its open position.
• a pressure medium reservoir 22 is arranged between the pressure relief valve 21 and the suction side 16 of the pump 12.
• the pressure side 13 and the suction side 16 of the pump 12 through one to the first line 14 and the second
• the actuating unit 1 includes a transducer 25 which measures the pressure in the cylinder space 15 and is referred to below as a pressure sensor.
• the actuation unit 1 and actuation units assigned to the other vehicle wheels can be controlled by the vehicle driver by means of a brake pedal 27, the pedal travel of which can be detected by a transducer 28, hereinafter referred to as the travel sensor.
• an electronic control unit 29 is provided with which the one electrical brake request signal of the displacement sensor 28 representing signal can be processed.
• the control device 29 With the control device 29, the electric motor 11 and the valves 18, 21, 24 of all actuating units 1 of the vehicle can be controlled.
• the signals measured by the pressure sensors 25 of the actuation units 1 can be processed in the control unit 28.
• slip-dependent signals which are detected on the vehicle wheels with wheel sensors (not shown), can be processed for the purpose of controlling the stability of the vehicle.
• control unit 28 contains slip-dependent signals, which are detected on the vehicle wheels with wheel sensors (not shown), for the purpose of slip control, e.g. Can be processed for a brake lock protection, traction control or driving stability control of the vehicle.
• the actuation unit 1 has the following functionality:
• the control unit 29 puts the electric motor 11 of the pump 12 into operation and the directional control valve 24 is switched into its blocking position, while the pressure build-up valve 18 and the pressure reduction valve 21 are activated maintain the position shown.
• the pump 12 sucks pressure medium from the reservoir 22 and conveys it through the first line 14 to the cylinder-piston unit 3, so that pressure is built up in the cylinder space 15 and the piston rod 6 the at least one brake pad 7 against the friction element 8 of the wheel brake 2 presses.
• the pressure rise rate can be set as a function of the course of the brake request signal.
• the pressure acting in the cylinder space 15 is determined by the pressure sensor 25 detected and its signal processed in the control unit 29.
• the directional control valve 24 is controlled into an intermediate position, so that the pressure medium conveyed by the pump 12 is discharged through the return line 23 to the suction side 16 of the pump while maintaining the brake pressure.
• the intermediate position of the directional control valve 24 is changed or this is switched to its open position. Due to the elasticity of the wheel brake 2, the piston 5 is reset and the pressure medium displaced from the cylinder chamber 5 is discharged through the first line 14 and the return line 23 into the pressure medium storage container 22.
• the pressure reduction rate can be set by means of the directional valve 24. When the braking process ends, the electric motor 11 is switched off.
• the actuation unit 1 can be used to modulate the pressure in the cylinder space 15 of the cylinder-piston unit 3 by means of the control unit 29. Phases for pressure build-up are realized in that the pressure build-up valve 18 assumes its open position and the pressure reduction valve 21 its blocking position when the pump 12 delivers pressure medium.
• Maintaining pressure is achieved by switching the pressure build-up valve 18 into its blocking position. Phases for pressure reduction are set in that the pressure build-up valve 18 maintains its blocking position and the pressure relief valve 21 is switched to the open position. In the case of faulty valves 18 and 21 and in the case of very rapid pressure reduction, relief of the cylinder space 15 is possible in that pressure medium is diverted through the bypass line 19 and the directional control valve 24 switched in the forward direction to the reservoir 22.
• the actuation unit 1 is a system that is self-sufficient for each vehicle wheel. Each actuation unit of the vehicle is advantageously connected to a separate energy supply or groups of actuation units are connected to separate energy supplies. In the event of a power supply failure, the remaining actuation units remain functional.

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

Applications Claiming Priority (3)

Publications (1)

Family

ID=7925802

Family Applications (1)

Country Status (5)

Families Citing this family (13)

Family Cites Families (16)

• 1999
  • 1999-10-15 DE DE19949816A patent/DE19949816A1/de not_active Withdrawn
• 2000
  • 2000-09-14 JP JP2001531642A patent/JP2003512239A/ja active Pending
  • 2000-09-14 WO PCT/DE2000/003201 patent/WO2001028833A1/de not_active Application Discontinuation
  • 2000-09-14 US US10/110,119 patent/US6623087B1/en not_active Expired - Fee Related
  • 2000-09-14 EP EP00974320A patent/EP1224105A1/de not_active Withdrawn

Non-Patent Citations (1)

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