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
  • B60T8/36—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
  • B60T8/366—Valve details
  • B60T8/3665—Sliding 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
  • 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
  • B60T13/10—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 fluid assistance, drive, or release
  • B60T13/66—Electrical control in fluid-pressure brake systems
  • B60T13/68—Electrical control in fluid-pressure brake systems by electrically-controlled valves
  • B60T13/686—Electrical control in fluid-pressure brake systems by electrically-controlled valves in hydraulic systems or parts thereof
• • 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
• • 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

Definitions

• the invention relates to a device for operating an anti-lock hydraulic brake system for a motor vehicle according to the preamble of claim 1. With such a brake system, the blocking of the
• Vehicle wheels prevented during braking. As a result, the motor vehicle remains steerable and stable at all times, even during full braking.
• Master cylinder and auxiliary pressure source are here via one
• Anti-lock device for the hydraulic brake system low investment costs for a vehicle to be equipped with it result that the uncomplicated training of the
• Anti-lock device of the hydraulic brake system makes the dynamic functional processes reliably manageable, making it a relatively easy retrofit for existing ones
• Anti-lock function work as per anti-lock
• Brake circuit only insert the valve device in the connecting line between the master cylinder and brake circuit, that the brake system has the functions for anti-lock protection and
• anti-lock hydraulic vehicle brake system to arrange a proportional valve controlled by a proportional magnet, wherein a control line running from the master cylinder to the valve device is provided, so that the
• Master cylinder pressure acts on an end face of the control slide of the valve device.
• valve device by excitation of the proportional magnet, the master cylinder pressure remains constantly on the face of the Control spool effective. In this way, the outlet pressure of the valve device is controlled as a function of the master cylinder pressure.
• Fig. 1 shows schematically an anti-lock hydraulic
• Fig. 2 force-displacement map of the proportional magnet.
• Motor vehicle has a master brake cylinder 11 which can be actuated by a brake pedal and is connected to the wheel brake cylinder 16 of a driven front vehicle wheel 18 via a first connecting line 12 and a second connecting line 15 with the interposition of a valve device 14.
• the controllable valve device 14 consists of a
• Proportional pressure valve 13 and a proportional magnet 26 are Proportional pressure valve 13 and a proportional magnet 26.
• proportional in connection with the magnet refers to the course of the characteristic in
• the housing 25 of the proportional pressure valve 13 has a control slide 20 guided in a bore 21 and four control openings 19, 22, 23, 24 opening radially into the bore 21.
• a return spring 40 holding the control slide 20 and the armature 28 in the rest position is arranged in a spring chamber 39 of the housing 25.
• the first connecting line 12 is connected to the first control opening 19 of the housing 25, while the second
• Connecting line 15 starts from a connection which is connected to the bore 21 of the housing 25.
• Control opening 22 is via a line 31, with a
• Reservoir 34 for brake fluid connected, from pump 29 and
• the pump 29 is used to automatically maintain the pressure in the pressure accumulator 30.
• a check valve 32 is arranged between the pump 29 and the pressure accumulator 30 and an expensive shut-off valve 33 is arranged in the line 31 between the pressure accumulator 30 and the housing 25.
• the third control opening 23 is through a line 36 to the second connecting line 15 and the fourth control opening 24 by means of line 35 to the reservoir 34 below Liquid level connected.
• the storage container 34 is open to the atmosphere and thus corresponds to a room of low pressure.
• the control slide 20, which is axially displaceable in the housing 25, has an end control surface 37 and a circumferential groove 38, between which a cylindrical guide section 58 is formed.
• the length of the guide section 58 is greater than the axial distance between the first and second control openings 19, 22.
• the axial width of the circumferential groove 38 never corresponds to the distance between the adjacent edges of the second and fourth control openings 22, 24.
• the spring chamber 39 is connected by a relief channel 56 the control opening 24 connected.
• the brake system is controlled by means of the conditions to be considered for the vehicle in question
• Programmable control electronics 42 as a function of the signals of the speed sensors 17 arranged on the anti-lock vehicle wheels 18 and the signal of a brake signal transmitter 51 arranged on the master brake cylinder 11.
• the control electronics 42 consist of a first evaluation module 43 for controlling the anti-lock function, which has signal inputs 41, 41a, 41b for all speed sensors, a second evaluation module 44 for controlling the traction control system, which has only signal inputs 41 and 41a for speed sensors of driven ones Has vehicle wheels and several
• Evaluation modules 43, 44 are connected to the signal inputs
• Control modules 47, 47a, 47b are connected, the signal outputs 45, 46 and 45a, 46a being connected to the control modules 47, 47a for driven vehicle wheels and the control module 47b associated with a non-tang driven vehicle degree being connected only to the signal output 45b of the evaluation module 43.
• the output signal lines 45, 46 lead to a control module 47, the output of which via a Signal line 48 is connected to the coil 27 of the proportional magnet 26.
• the brake signal generator 51 is connected through a signal line 50 with all the control modules 47, 47a arranged in the control electronics 42,
• the evaluation modules 43, 44 of the control electronics 42 each have a further signal output 52, 53, which are connected to the shut-off valve 33 via a signal line 49.
• the functional sequence of an anti-lock braking with the brake system according to the invention is as follows: When initiating a braking operation by actuating the master brake cylinder 11, a brake pressure builds up which is greater than the first
• Control modules 47, 47a, 47b in the control electronics 42 As a result, the output signal line 4.5 of the evaluation module 43 for the anti-lock function from the control module 47 to the
• Proportional magnets 26 leading signal line 48 are Proportional magnets 26 leading signal line 48
• the evaluation module 43 has a map memory that is matched to the vehicle and contains the programmed association between the determined critical speed values and the corresponding excitation current for the coil 27 of the proportional magnet 26. If the evaluation module 43 detects such a speed value, the coil 27 of the proportional magnet 26 is energized with a specific current by the control module 47 via the signal line 48.
• shut-off valve 33 is switched to continuity by a signal from the signal output 52, so that the pressure of the Pressure accumulator 30 is present in the second control opening 22 of the proportional pressure valve 13.
• the excitation of the coil 27 results in an axial movement of the armature 28, as a result of which the control slide 20 is displaced from the rest position shown in FIG. 1.
• the proportional magnet 26 operates in the first startup area 54 of its
• frontal control surface 37 slides over the first control opening 19 and interrupts the connection between the first and second connecting lines 12, 15. The pressure in
• the control slide 20 with its circumferential groove 38 is approximately opposite the third control opening 23, but has not yet passed the fourth control opening 24 with the right control edge of the circumferential groove 38.
• the excessive brake pressure in the wheel brake cylinder 16, which would cause the vehicle wheel 18 to lock, can then be transmitted via the connecting line 15,
• Proportional magnets 26 As the pressure in the wheel brake cylinder 16 drops, the pressure present on the front control surface 37 of the control slide 20 also drops. The force which counteracts the instantaneous actuating force of the proportional magnet 26 is thus
• Actuating force on armature 28 with constant excitation of coil 27 causes a further displacement of control spool 20 until the left control edge of circumferential groove 38 opens second control opening 22.
• the brake pressure value in the wheel brake cylinder 16 is now raised again via the circumferential groove 38, the third control opening 23, line 36 and connecting line 15 to the extent that the actuating force of the armature 28 caused by the control signal of the evaluation module 43 and the from the
• control slide 20 In the state of equilibrium of the forces, the control slide 20 assumes a position in which the control edges of the circumferential groove 38 are just congruent with the adjacent edges of the
• Control ports 22 and 24 are. This position arises when the anti-lock vehicle wheel is decelerated with optimum braking effect.
• the circumferential groove 38 and control openings 22, 24 have the function of a pressure modulator in this position of the control slide 20.
• the brake pressure value is in each case proportional to the current strength controlled by the evaluation module 43 or the excitation of the coil 28 of the proportional magnet 26 caused thereby, and is suitable for preventing the vehicle wheel 18 from blocking.
• the brake signal generator 51 becomes inactive.
• the control module 47 thereby falls back into its rest position, whereby the connection between the evaluation module 43 and the control module 47 is disconnected the excitation of the proportional magnet 26 is ended , armature 28 and control slide 20 are returned to their rest position by the return spring 40.
• the connecting line 12 to the second connecting line 15 is thus released again by the control slide 20.
• the shut-off valve 33 is also deactivated by the control electronics 42, so that the line 31 is blocked again.
• control module 47 When the master brake cylinder 11 is not actuated, the control module 47 is always in the position in which the signal output 46 of the evaluation module 44 for the traction control system on
• Control module 47 is effective. If necessary, the coil 27 of the proportional magnet 26 can be excited at any time via the signal line 48.
• the traction control system is automatically activated by the control electronics 42 if, for example, during an acceleration process of the vehicle. B. when starting, during an overtaking or in road smoothness, the evaluation of the signals of the speed sensor 17 in the evaluation module 44 results in an acceleration value that indicates a slipping of the driven vehicle wheel 18.
• the evaluation module 44 has a matched to the vehicle
• Map memory on which the programmed assignment between the determined critical acceleration values and the corresponding excitation current for the coil 27 of the
• Proportional magnets 26 contains.
• the control module 47 then generates on the basis of one of the
• Evaluation module 44 sent command a control signal bes certain current with which the coil 27 of the proportional magnet 26 is excited.
• the shut-off valve 33 is switched to passage by a signal via the signal output 53 and the signal line 49, so that the pressure of the high pressure source 59 is present in the second control opening 22 of the proportional pressure valve 13.
• Control slide 20 displaced by the armature 28 of the proportional magnet 26 to such an extent that the front control surface 37 slides over the first control opening 19 and interrupts the connection between the first and second connecting lines 12, 15.
• the brake pressure value is also present on the front control surface 37 of the control slide 20 via the second connecting line 15, so that there is a counterforce to the actuating force of the armature 28. In the state of equilibrium of the forces
• Control slide 20 a position in which the control edges of the circumferential groove 38 are just congruent with the adjacent edges of the control openings 22 and 24. Circumferential groove 38 and
• Control slide 20 the function of a pressure modulator.
• a braking pressure value is temporarily formed in the circumferential groove 38 or in the wheel brake cylinder 16 by alternately briefly opening the second control opening 22 and the fourth control opening 24.
• This temporary brake pressure value is in each case proportional to the current strength controlled by the evaluation module 43 or the excitation of the coil 28 caused thereby
• Proportional magnets 26 and suitable to prevent uncontrolled slippage or the spinning of the driven vehicle wheel 18.
• the adhesion limit between the tire and the road surface is not exceeded.
• the vehicle wheel can therefore support lateral forces at all times and always remains steerable.
• the evaluation module 44 can optionally also have an additional signal output (not shown), from which a signal for influencing operating variables of the vehicle drive system can be tapped during a traction control cycle.
• Proportional pressure valve 13 are very small. The hysteresis of the hydraulic brake system is therefore negligible. It follows that the excitation current for the coil 27 of the
• Proportional magnets 26 is actually proportional to the pressure-modulated brake pressure value in the proportional pressure valve 13. This application of the proportional technique for influencing the brake pressure value in the wheel brake cylinder with anti-lock or traction control function has an analogous effect
• Control slide 20 the course of the force P developable by the armature 28 for different excitation currents A1, A2, A3 of the coil 27.
• the spring chamber 39 can be connected to the first connecting line 12 via a channel 57 (indicated by dash-dotted lines in FIG. 1) instead of the relief channel 56 leading to the room pressure.
• a channel 57 indicated by dash-dotted lines in FIG. 1
• the pressure generated in the master brake cylinder 11 prevails in the spring chamber and the gap surrounding the armature 28. This causes when activated
• Anti-lock function that the force resulting from the brake pressure on the front control surface 37 is partially compensated for by the pressure prevailing in the spring chamber 39.
• a commercially available pressure relief valve 60 can be inserted into the first connecting line 12
• Master brake cylinder 11 automatically generated maximum brake pressure limited.

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

Applications Claiming Priority (2)

Publications (1)

Family

ID=6417504

Family Applications (1)

Country Status (2)

Cited By (6)

Families Citing this family (15)

Citations (4)

Family Cites Families (1)

• 1990
  • 1990-11-02 DE DE19904034839 patent/DE4034839C1/de not_active Expired - Lifetime
• 1991
  • 1991-10-30 WO PCT/EP1991/002056 patent/WO1992007743A1/de active Application Filing

Patent Citations (4)

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