Abstract: Provided is an electric brake capable of accurately estimating the brake pad temperature and securing a sufficient braking force and response. An electric brake has a disc rotor rotating with a wheel, an actuator for rectilinearly actuating a piston in the axial direction of the disc rotor by using an electric motor, a drive controller for controlling the drive of the actuator, a brake pad pressed by the piston to give a frictional resistance to the disc rotor in the direction of rotation, and a braking start position detector for detecting a braking start position of the piston where the disc rotor is brought into contact with the brake pad. The drive controller stores the braking start position detected by the braking start position detector as the maximum braking start position. When the braking start position shifts in the pressing force-increasing direction, the drive controller updates the value stored as the maximum braking-start position.

Abstract: A motor-driven disk brake system is capable of preventing a pressing member from moving beyond a predetermined position at a time of stopping a motor. When a command for system termination is issued, motor current is reduced intermittently, which correspondingly reduces a motor displacement gradually such that a return force is spent gradually on a return displacement of a motor and a piston, thereby preventing a rotational speed of a rotor from increasing. A large accelerated backward movement of the motor and the piston beyond a predetermined position due to inertia is thereby prevented, because the return force does not act all at once during the return displacement of the motor and the piston. Accordingly, the piston is stopped near a standby position of non-braking state before system termination. As a result, a next activation of the motor-driven disk brake system can be conducted promptly.

Abstract: An electro-mechanical brake achieves a safe traveling and braking with a high accuracy device for detecting a piston position at which a brake pad and a disk rotor contact each other. A pad contact position detecting device in which an electric circuit is not formed to prevent an electric current from flowing therethrough when a pad pressing force is not generated and the electric circuit is formed to enable the electric current to flow therethrough when the pad pressing force is generated is applied to the electro-mechanical brake. A pad contact position can thereby be detected accurately.

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: Provided is an electric brake capable of accurately estimating the brake pad temperature and securing a sufficient braking force and response. An electric brake has a disc rotor rotating with a wheel, an actuator for rectilinearly actuating a piston in the axial direction of the disc rotor by using an electric motor, a drive controller for controlling the drive of the actuator, a brake pad pressed by the piston to give a frictional resistance to the disc rotor in the direction of rotation, and a braking start position detector for detecting a braking start position of the piston where the disc rotor is brought into contact with the brake pad. The drive controller stores the braking start position detected by the braking start position detector as the maximum braking start position. When the braking start position shifts in the pressing force-increasing direction, the drive controller updates the value stored as the maximum braking-start position.

Abstract: A brake control apparatus for a vehicle having brake devices for generating pad-pressing forces at respective wheels includes brake control units for individually controlling the pad-pressing forces at the respective wheels; a storing unit for storing drive data required for controlling the pad-pressing force at each wheel; a vehicle-driving-state detector for detecting a driving state of the vehicle; and a vehicle controller for controlling a vehicle driving state using the brake control unit for each wheel. Memory data representing the relationship between a motor position and the pad-pressing force is updated using the state of brake actuators obtained when the driving state of the vehicle is stabilized by operating the brake devices during braking.

Abstract: An electrically operated brake device in which braking force differences between electrically operated brakes are reduced to prevent unstable vehicle traveling during braking. Motors 13 of electrically operated brakes are returned to standard positions during the stop of a vehicle and the motor 13 of each of the brakes is driven for a predetermined amount, pressing a brake pad 17 against a disc rotor 18 to produce a braking force. An electric current value of each motor 13 in the above operation is measured and differences between the values are calculated. Electric current of each motor is increased or decreased so that there is no current difference between the motors 13. Based on a drive amount of each motor in this operation, standard positions of the motors are determined and updated. Repeating the above operations reduces braking force differences between the brakes.

Abstract: An electrically operated brake device in which braking force differences between electrically operated brakes are reduced to prevent unstable vehicle traveling during braking. Motors 13 of electrically operated brakes are returned to standard positions during the stop of a vehicle and the motor 13 of each of the brakes is driven for a predetermined amount, pressing a brake pad 17 against a disc rotor 18 to produce a braking force. An electric current value of each motor 13 in the above operation is measured and differences between the values are calculated. Electric current of each motor is increased or decreased so that there is no current difference between the motors 13. Based on a drive amount of each motor in this operation, standard positions of the motors are determined and updated. Repeating the above operations reduces braking force differences between the brakes.

Abstract: A motor-driven disk brake system capable of preventing a pressing member from moving beyond a predetermined position at a time of stopping a motor. When a command for system termination is issued, a process of alternate intervals A and B is conducted to reduce a motor current intermittently and to correspondingly reduce a motor displacement gradually, such that a return force such as a torque stored in a coil spring (return spring) is spent gradually on a return displacement of a motor 11 and a piston, so as to prevent a rotational speed of a rotor from increasing. In this way, a motor displacement and an operation of returning a piston can be stopped smoothly. Therefore, it is possible to prevent a large accelerated backward movement of the motor 11 and the piston (thus a backward movement of the piston beyond a predetermined position) due to inertia, which may occur when the return force acts all at once on the return displacement of the motor 11 and the piston.

Abstract: A brake control apparatus for a vehicle having brake devices for generating pad-pressing forces at respective wheels includes brake control units for individually controlling the pad-pressing forces at the respective wheels; a storing unit for storing drive data required for controlling the pad-pressing force at each wheel; a vehicle-driving-state detector for detecting a driving state of the vehicle; and a vehicle controller for controlling a vehicle driving state using the brake control unit for each wheel. Memory data representing the relationship between a motor position and the pad-pressing force is updated using the state of brake actuators obtained when the driving state of the vehicle is stabilized by operating the brake devices during braking.

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 electro-mechanical brake for obtaining a safe traveling and braking with a high accuracy means for detecting a piston position at which a brake pad and a disk rotor contact each other is provided. A pad contact position detecting device in which an electric circuit is not formed to prevent an electric current from flowing therethrough when a pad pressing force is not generated and the electric circuit is formed to enable the electric current to flow therethrough when the pad pressing force is generated is applied to the electro-mechanical brake, whereby a pad contact position can be detected accurately to improve an accuracy in controlling a braking force so that the electro-mechanical brake enabling the safe traveling and braking to be obtained can be provided.