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
• • 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
• • 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
  • F16D2121/18—Electric or magnetic
  • F16D2121/24—Electric or magnetic using motors
• • 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
• • 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
  • F16D2125/58—Mechanical mechanisms transmitting linear movement
  • F16D2125/587—Articulation, e.g. ball-socket
• • 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
  • F16D2127/00—Auxiliary mechanisms
  • F16D2127/02—Release mechanisms
• • 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
  • F16D2127/00—Auxiliary mechanisms
  • F16D2127/02—Release mechanisms
  • F16D2127/04—Release mechanisms for manual operation
• • 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
  • F16D2127/00—Auxiliary mechanisms
  • F16D2127/06—Locking mechanisms, e.g. acting on actuators, on release mechanisms or on force transmission mechanisms

Definitions

• the invention relates to a method for operating an electromechanical wheel brake device with the features of the preamble of claim 1.
• An electromechanical wheel brake device is known from WO96 / 03301.
• the known wheel brake device has an electric motor with which a spindle drive can be driven in rotation.
• the spindle drive converts the rotary movement of the electric motor into a translatory movement which serves to press and release a friction brake lining against a brake body connected in a rotationally fixed manner to a vehicle wheel.
• the known wheel brake device is designed as a disc brake, so the brake body is a brake disc.
• the wheel brake device can also be designed as a drum brake, in which the brake body is a brake drum, or in another brake design.
• the electric motor of the wheel brake device is energized in a forward direction of rotation, so that the Friction brake lining is pressed onto the brake body and exerts a braking force (braking torque) on the brake body.
• a desired braking force is reached, the setpoint of which is determined, for example, by a sensor on a foot brake pedal depending on the force with which the foot brake pedal is depressed and / or depending on the distance by which the foot brake pedal is depressed, the energization of the electric motor is ended.
• the braking force exerted on the brake body (actual value) is determined with a braking force sensor and compared with the soli value.
• the known wheel brake device has the disadvantage that, due to the kinetic energy of the rotating electric motor and the spindle drive, the electric motor and the spindle drive continue to run a short distance after the current supply has ended. This has the consequence that the wheel brake device comes to a standstill with a time delay and the braking force rises above the desired value.
• the increase in braking force after the energization of the electric motor has ended depends, inter alia, on the motor speed and thus on whether the wheel brake device is actuated from the released position or whether the braking force has been increased during braking.
• the increase in braking force after the end of the current supply depends on the pressing force of the friction brake lining against the brake body and thus on the level of the braking force of the wheel brake device.
• the increase in braking force after the end of the current supply to the electric motor is greater than with a high braking force.
• the increase in braking force beyond the desired braking force cannot therefore be countered simply by stopping the energization of the electric motor shortly before the desired braking force is reached.
• Another disadvantage of the known wheel brake device is that in order to reduce the braking force and to completely release the wheel brake device, its electric motor is supplied with current in a reverse rotation direction and must be accelerated together with the spindle drive.
• the wheel brake device is used dynamically, that is to say a change between increasing the braking force, keeping the braking force constant and reducing the braking force in rapid succession, as occurs in the case of anti-lock control, this becomes cumbersome Wheel brake device noticeably noticeable, the known wheel brake device can at most be used to a limited extent for anti-lock braking.
• the electromechanical wheel brake device for performing the method according to the invention with the features of claim 1 has a releasable anti-rotation device, such as a magnetic brake, with which a part of the spindle drive pressing the friction brake lining against the brake body, i.e. the spindle or the nut, rotates and is axially displaceable, for example a polygonal or serrated profile.
• a releasable anti-rotation device such as a magnetic brake, with which a part of the spindle drive pressing the friction brake lining against the brake body, i.e. the spindle or the nut, rotates and is axially displaceable, for example a polygonal or serrated profile.
• the anti-rotation device is briefly released, as a result of which the translational movement of the friction brake lining and the part of the self-locking spindle drive that presses against the brake body come to an abrupt stop, even if a rotating part of the spindle drive and the electric motor are removed of their kinetic energy continue to rotate without current.
• the braking force is not increased above the desired value by briefly releasing the anti-rotation device of the part of the spindle drive pressing the friction brake lining against the brake body.
• Self-locking means that the nut of the spindle drive is rotated and the spindle is axially displaced by an axial force, for example on the spindle of the spindle drive.
• the axial force exerted on the spindle is a reaction force to the pressing force with which the friction brake lining is pressed against the brake body.
• the anti-rotation device is also released to reduce the braking force, as a result of which the braking force of the wheel brake device is reduced independently of a rotation of the electric motor.
• the method according to the invention has the advantage of highly dynamic operation of the electromechanical wheel brake device. A quick change between increasing, keeping constant and reducing the braking force is possible.
• the electromechanical wheel brake device can thus also be used for anti-lock control.
• Another advantage of the invention is the possibility of releasing the wheel brake device in the event of a fault in the case of a non-rotating electric motor by releasing the anti-rotation device.
• the released anti-rotation device of the wheel brake device can be engaged during the run, it acts in particular frictionally and can be engaged at any time while the braking force of the wheel brake device is being reduced.
• the wheel brake device 10 according to the invention shown in FIG. 1 is designed as a disc brake device. It has a brake caliper 12, in which two friction brake linings 14 are attached in a manner known per se, between which a rotatable brake disk 16, which is fixedly connected to a vehicle wheel (not shown), is arranged as a brake body. On the side of one of the two friction brake linings 14, the brake caliper 12 has an approximately cylindrical cavity 18 which is aligned perpendicular to the brake disc 16 and the friction brake linings 14. A spindle drive 20 and an electric motor 22 are accommodated in the cavity 18, the brake caliper 12 forms a housing for the spindle drive 20 and the electric motor 22.
• the spindle drive 20 is designed as a roller screw drive. It has a nut 24 which is rotatably mounted in the brake caliper 12 with an inclined roller bearing 26.
• the inclined roller bearing 26 supports the nut 24 in particular in the direction axially towards the brake disk 16.
• a spindle 28 of the spindle drive 20 is located coaxially within the nut 24.
• the spindle 28 is not directly in engagement with the nut 24, between the spindle 28 and the nut 24 there is an annular space in cross section in which a number is distributed over the circumference of thread rolls 30 are arranged.
• the thread rolls 30 engage both with a thread of the nut 24 and with a thread of the spindle 28. By rotating the nut 24, the thread rolls 30 are driven to rotate around the spindle 28.
• the thread rolls 30 roll on the spindle 28, they rotate about their own axes.
• the movement of the thread rolls 30 is comparable to the movement of planet wheels of a planetary gear. Due to the thread pitches of the nut 24, the thread rolls 30 and the spindle 28, the rotating movement of the nut 24 is converted into a translatory movement of the spindle 28, the spindle 28 is displaced in the axial direction.
• the thread rolls 30 can have a pitch of zero, that is to say they are provided with circumferential grooves with a thread profile instead of with a thread, in this case, strictly speaking, they are not thread foils. Nevertheless, it results from the thread pitches of the nut 24 and the spindle 28 translate the spindle 28 when the nut 24 is driven in rotation.
• the electric motor 22 is provided for rotating the nut 24 of the spindle drive 20.
• the nut 24 also forms a rotor 24 of the electric motor 22.
• permanent magnets 32 are attached to the circumference of the nut 24.
• Stator windings 34 and stator laminations 36 of the electric motor 22 surround the nut 24 forming the rotor 24 in a fixed manner in the brake caliper 12 forming the housing of the electric motor 22 and the spindle drive 20.
• the roller screw 20 is designed to be self-locking, i. H. by axial pressure against the spindle 28, the nut 24 can be rotated and the spindle moved.
• An end of the spindle 28 of the roller screw drive 22 facing the friction brake linings 14 and the brake disk 16 is designed as a spherical cap 38.
• a sealing collar 40 holds the friction brake lining 14 facing the spindle 28 in contact with the calotte 38.
• the sealing collar 40 is designed as a bellows which surrounds the spindle 28 at its end.
• the sealing sleeve 40 is inserted into the brake caliper 12 forming the housing for the spindle drive 20 and the electric motor 22 and is attached with its other end to the friction brake lining 14 facing the spindle 28. Since the spindle 28 with its spherical cap 38 only abuts the friction brake lining 14, the spindle 28 can be rotated with respect to the friction brake lining 14.
• the wheel brake device 10 has a releasable anti-rotation device 42, which is inserted into a housing cover 44, which accommodates the cavity 18 of the brake caliper 12, in which the spindle drive 20 and the electric motor 22 are accommodated, on one of the brake discs 16 opposite side closes.
• the detachable anti-rotation device 42 can be designed, for example, as a switchable freewheel, as is known to the person skilled in the art different embodiments are known per se.
• a frictional electromagnetic brake 42 has been selected as a releasable anti-rotation device 42.
• the electromagnetic brake 42 has a yoke-shaped armature plate 46 which is pressed by a set of helical compression springs 48 against a brake disc 50 which is arranged between the armature plate 46 and the housing cover 44 and which is exerted against the housing cover by the pressure springs 48 which are exerted on the armature plate 46 44 is pressed.
• the brake disc 50 is thus clamped in a rotationally fixed manner by the force of the helical compression springs 48 by frictional engagement between the anchor plate 46 and the housing cover 44.
• the brake disc 50 is connected in a rotationally fixed and axially displaceable manner to the spindle 28 of the spindle drive 20 via a multi-groove profile 52, i. H. the spindle 28 can be moved in the brake caliper 12 in the axial direction and is secured against rotation when the electromagnetic brake 42 is closed.
• the multi-groove profile 52 is mounted in a hub 54 of the brake disc 50 and on a sleeve 56, the sleeve 56 being firmly pressed onto an axial spindle pin 58 which is integral with the spindle 28.
• To release the electromagnetic brake 42 has a coil 60 which is mounted in a recess in an annular poi 62.
• the pole piece 62 is arranged on a side of the armature plate 46 facing away from the brake disk 50.
• blind holes 64 are made, into which the helical compression springs 48 are inserted, which press the anchor plate 46 against the brake disc 50.
• a reduced or clocked energization of the coil 60 allows a brake slip of the electromagnetic brake 42 to be set, ie a braking torque exerted by the armature plate 46 on the brake disc 50 can be limited so that the spindle 28 can be rotated by overcoming the braking torque of the electromagnetic brake 42.
• the function of the wheel brake device 10 is as follows: To actuate the wheel brake device 10, the electric motor 22 is energized in a forward direction of rotation, as a result of which the nut 24 of the spindle drive 20 is rotated and the spindle 28 is displaced in the direction of the brake disk 16.
• the spindle 28 presses the friction brake lining 14 arranged on its side of the brake disc 16 against the brake disc 16 and, via a reaction force, the other friction brake component 14 is pressed against the other side of the brake disc 16 in a manner known per se via the brake caliper 12 designed as a floating caliper.
• the energization of the electric motor 22 is stopped or the current is reduced to a value that maintains the desired braking force.
• the electric motor 22 is energized with reverse polarity, that is to say in a reverse rotation direction.
• the electromagnetic brake 42 is closed, i. H. its coil 60 is de-energized, the electromagnetic brake 42 holds the spindle 28 in a rotationally fixed manner in the brake caliper 12.
• the electromagnetic brake 42 is briefly released by energizing its coil 60 when the desired braking force is reached.
• the spindle 28 of the spindle drive 20 is freely rotatable and it no longer moves axially in the direction of the brake disc 16, even if the nut 24 continues to rotate due to the kinetic energy.
• the application of the wheel brake device 10 comes to an abrupt stop due to the brief release of the electromagnetic brake 42.
• a further possibility of limiting the braking force of the wheel brake device 10 when the brake is applied to a predetermined value is, according to the invention, to energize the electromagnetic brake 42 with a reduced or clocked current which is selected to be large enough that it flows from the helical compression springs 64 onto the anchor plate 46 force exerted partially compensated.
• the brake disc 50 of the electromagnetic brake 42 is thereby clamped with reduced force between the armature plate 46 and the housing cover 44, as a result of which the spindle 28 can be rotated by overcoming the braking torque set by energizing the electromagnetic clutch 42.
• Reduced energization means an energization that does not lift the armature plate 46 off the brake disk 50, but rather partially compensates for the pressing force of the helical compression springs 64 and thus reduces it.
• the torque exerted by the nut 24 via the thread rollers 30 on the spindle 28 when tightening is dependent on the pressing force with which the spindle 28 presses the friction brake linings 14 against the brake disk 16.
• This means that the pressure force of the friction brake linings 14 on the brake disc 16 and thus the braking force exerted on the brake disc 16 is dependent on the braking torque set on the electromagnet brake 42 by energizing its coil 60. It can also be avoided by controlling the braking torque of the electromagnetic brake 42 that the braking force of the wheel brake device 10 infoige the kinetic energy of the spindle drive 20 and the electric motor 22 increases to a higher value than desired.
• the electromagnetic brake 42 can also be released to reduce the braking force of the wheel brake device 10, as a result of which the spindle 28 can be rotated.
• the friction brake lining 14 pressed against the brake disc 16 by the spindle 28 presses the spindle 28 away from the brake disc 16 and sets the spindle 28 of the self-locking spindle drive 20 in rotation, as a result of which the braking force of the wheel brake device 10 is reduced. In this way, the braking force of the wheel brake device 10 can be reduced without the electric motor 22 having to be energized in the reverse direction.
• one embodiment of the method according to the invention provides for briefly energizing the electric motor 22 to a standstill with reverse polarity, that is to say in the reverse direction.
• the invention provides for the electric motor 22 to be energized in the forward direction of rotation and the electromagnet brake 42 to increase the braking force of the wheel brake device 10, to keep the braking force of the wheel brake device 10 constant, to adjust the braking torque of the electromagnet brake 42 by reduced or clocked energization to a desired value which corresponds to the desired braking force of the wheel brake device 10 and to reduce the braking force of the wheel brake device 10 To release the electromagnetic brake 42 completely.
• the electric motor 22 can continue to maintain and decrease the braking force of the wheel brake device 10 be energized, its energization can be reduced or interrupted. In particular, if the electric motor 22 is continuously energized and thereby continues to rotate in the forward direction of rotation even while keeping constant and reducing the braking force of the wheel brake device 10, there is a considerable gain in dynamics of the wheel brake device 10, which enables a slip control.
• a dynamic gain can also be achieved for an emergency braking situation.
• the electromagnetic brake 42 is released, as a result of which the spindle 28 can be rotated, and the electric motor 22 is energized in the forward direction of rotation.
• the electric motor 22 thereby accelerates to approximately its idling speed, the friction brake pads 14 apply to the brake disc 16 with a low pressure force, which causes the spindle 28 to rotate with the rotatingly driven nut 24 of the spindle drive 20, and the displacement of the spindle 28 in the direction of the Brake disc 16 ended.
• a braking force is now to be built up, only the electromagnetic brake 42 is closed and the already rotating electric motor 22 very quickly increases the pressing force of the friction brake linings 14 on the brake disk 16 via the spindle drive 20.
• the braking and starting of the electric motor 22 at the start of the emergency braking accelerates and accelerates not applicable.
• An emergency braking situation can be ascertained, for example, when a driver leaves an accelerator pedal with high gradients, which can be ascertained without problems by means of a corresponding sensor.
• the electromagnetic brake 42 of the wheel brake device 10 is released and the electric motor 22 is energized. If the driver moves his foot from the accelerator pedal to the brake pedal and depresses it, the braking force of the wheel brake device 10 can be increased very quickly to the desired value.

Landscapes

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

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=7892160

Family Applications (1)

Country Status (5)

Families Citing this family (12)

Citations (4)

• 1998
  • 1998-12-22 DE DE19859325A patent/DE19859325A1/de not_active Withdrawn
• 1999
  • 1999-07-13 EP EP99947200A patent/EP1140598A1/de not_active Withdrawn
  • 1999-07-13 KR KR1020017007857A patent/KR20010093205A/ko not_active Application Discontinuation
  • 1999-07-13 JP JP2000589386A patent/JP2002532672A/ja active Pending
  • 1999-07-13 WO PCT/DE1999/002157 patent/WO2000037296A1/de not_active Application Discontinuation

Patent Citations (4)

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