Abstract: Even when a rigidity table stored in a RAM at the time of a start of a brake operation does not coincide with a actual rigidity characteristic (pressing force characteristic in relation to positions) of an electric caliper which changes according to brake conditions including how often and how long a brake operation is applied, it is possible to reduce a deviation between a pressing force instruction value and a generated pressing force by updating the characteristic of the relation between a pressing force instruction value and rotational position (rigidity table) each time an estimated thrust force value is calculated during one brake operation. In other words, it is possible to steadily keep followability to a pressing force instruction according to an actual state of the rigidity characteristic of the electric caliper, thereby ensuring generation of an appropriate brake force.

Abstract: The invention provides an electro-mechanical brake system which can keep a stop state even if a malfunction is generated in a parking brake, and an electro-mechanical brake apparatus used for the electro-mechanical brake system. An electro-mechanical brake actuator presses a brake pad to a disc rotor so as to independently brake a braking force of each of wheels. A parking brake is constituted by a pawl portion attached to a motor of a motor driving the electro-mechanical actuator and a latch. A main controller detects a failure of the parking brake on the basis of a motor displacement at a time of reducing a motor current, and increases the pressing force in the remaining normal parking brake in the case that the parking brake failure in one wheel or more is detected.

Abstract: A brake apparatus is provided that can make a ratio between a front wheel braking force and a rear wheel braking force that is actually generated into an arbitrary ratio.

Abstract: An electric booster according to the present invention comprises a booster piston disposed around an input piston so as to movable relative to the input piston. The booster piston and input piston also serve as a primacy piston of a tandem master cylinder. A brake fluid pressure is generated in the tandem master cylinder by an input thrust force provided from a brake pedal to the input piston and a booster thrust force provided from the electronic actuator to the booster piston. In this electric booster, a slide hole is formed through the secondary piston of the tamed master cylinder in the axial direction therefore, and a rod member is slidably disposed through the slide hole. When the fluid pressure is not increased in the primary pressure chamber, due to the fluid pressure in the secondary pressure chamber, the rod member comes to abut against the input piston, and a reactive force in the secondary pressure chamber is returned to the brake pedal.

Abstract: An object of the present invention is to provide a brake apparatus in which a hydraulic pressure in a master cylinder is prevented from being increasingly varied while an anti-lock brake system is in operation, and therefore a pedal feeling can be improved. The brake apparatus comprises an electric booster including an input member which moves forward or backward in response to an operation of a brake pedal, an assist member which moves forward or backward by being driven by an electric actuator using an electric motor as its driving source. The electric booster generates a boosted brake hydraulic pressure in the master cylinder under an input thrust provided to the input member through the brake pedal and an assist thrust provided to the assist member by the electric actuator.

Abstract: An electric braking apparatus which first moves a piston in a detaching direction or passes a current to move the piston in the detaching direction in order to detect a pad contacting position. Furthermore, while the piston moves in the detaching direction, pad non-contact judgment is performed. After a pad non-contact state is confirmed, the piston is moved in a pressing direction to detect the pad contacting position. When the piston does not move in the detaching direction, it is judged that a parking brake has an ON-state, and it is waited until a host system instructs parking brake release.

Abstract: The disc brake apparatus includes a disc brake having a parking brake mechanism operated by an electric motor as a drive source to mechanically hold a piston, which has been moved forward by a hydraulic pressure supplied from a hydraulic control unit into a caliper, in a braking position even after the hydraulic pressure is released; and a controller for supplying a predetermined amount of hydraulic pressure from the hydraulic control unit to the caliper, based on a parking-brake indicating signal from a parking brake switch and for operating the parking brake mechanism, wherein, in a case in which a brake pedal is being operated when a parking-brake indicating signal is input, the parking brake mechanism is operated in a state in which a hydraulic pressure in the caliper is at a predetermined pressure, after the operation of the brake pedal is finished, so as to reduce a hydraulic pressure required for a release of a brake pedal.

Abstract: The invention provides an electro-mechanical brake system which can keep a stop state even if a malfunction is generated in a parking brake, and an electro-mechanical brake apparatus used for the electro-mechanical brake system. An electro-mechanical brake actuator presses a brake pad to a disc rotor so as to independently brake a braking force of each of wheels. A parking brake is constituted by a pawl portion attached to a motor of a motor driving the electro-mechanical actuator and a latch. A main controller detects a failure of the parking brake on the basis of a motor displacement at a time of reducing a motor current, and increases the pressing force in the remaining normal parking brake in the case that the parking brake failure in one wheel or more is detected.

Abstract: An electric braking apparatus is disclosed in which a rotational movement from a motor is converted into linear movement that moves a brake piston to generate braking force. The electric brake apparatus can perform full parking brake function without sacrificing its original braking function. In operation, immediately after generation of braking force caused by rotation of the rotor (26) supply of electricity to the motor is turned off. After supply of electricity is turned off, however, the rotor (26) is restricted from returning to its original position due to an engagement with an engaging claw (54) via a claw wheel (50), thereby keeping the barking brake remain effective. When electricity is thereafter supplied to the motor, the rotor (26) generates rotational torque sufficiently strong to push down the engaging claw (54) for disengagement, thereby releasing the parking brake.

Abstract: An electric braking apparatus is disclosed in which a rotational movement from a motor is converted into linear movement that moves a brake piston to generate braking force. The electric brake apparatus can perform full parking brake function without sacrificing its original braking function. In operation, immediately after generation of braking force caused by rotation of the rotor 26, supply of electricity to the motor is turned off. After supply of electricity is turned off, however, the rotor 26 is restricted from returning to its original position due to an engagement with an engaging claw 54 via a claw wheel 50, thereby keeping the barking brake remain effective. When electricity is thereafter supplied to the motor, the rotor 26 generates rotational torque sufficiently strong to push down the engaging claw 54 for disengagement, thereby releasing the parking brake.

Abstract: A motor-driven brake apparatus has a motor and a ball screw that converts rotational motion of the motor into rectilinear motion of a screw member. A position detector detects a stroke position of the screw member. A controller controls the motor on the basis of the result of detection by the position detector. The controller controls the motor so as to change the clearance between an inner pad (outer pad) and a disk according to vehicle running conditions.

Abstract: The present invention relates to an improved antiskid control apparatus for vehicles. When the front wheel on either one of the right and left sides is antiskid-controlled, this apparatus detects whether the road surface is in the condition of split .mu. in which the road surface friction coefficient is different between the right and left wheels by more than the prescribed value. When the road surface is found to have a split .mu. condition, antiskid control should be implemented on the front wheel mentioned above. To control the rise in brake fluid pressure, the other front wheel must then be shifted in whatever direction facilitates control of the threshold value. In other words, even if a wheel does not attain a sufficient coefficient of surface friction, antiskid control is needed to control easily the rise in brake fluid pressure. A large side force is applied continuously to the vehicle, thereby reducing slippage and cancelling the yaw moment.

Abstract: The present invention related to an improved antiskid control apparatus. When the front wheel on either the right and left sides becomes subject to antiskid control, this apparatus detects whether or not the road surface has a split .mu. condition in which the road surface friction coefficient at the right and left wheels differs by more than a prescribed value. When the road surface is determined to be in a split .mu. condition, the braking power for the rear wheels is lowered stepwise during antiskid control to suppress spinning and secure a large side force. This side force cancels the yaw moment which is generated by the difference of friction coefficients in the running direction on the right and left wheels.