A hydraulic pressure braking force generation device is provided with a first control unit for performing control for inhibiting excessive responses in which the input pressure is controlled such that the output pressure is within a first region set using a braking target oil pressure as a reference, a second control unit for performing control for responsiveness in which the increase speed or decrease speed of the input pressure is increased so as to be larger than that in the control for inhibiting excessive responses, to cancel response delay and a switching unit which, on the basis of the state of the braking target oil pressure, switches between the control for inhibiting excessive responses performed by the first control unit and the control for responsiveness performed by the second control unit.

A braking control device controllable in cooperation with a regenerative brake includes a case member fixed to the master cylinder, a first electric motor fixed to the case member, a second electric motor fixed to the case member independently of the first electric motor, a linearly movable input rod mechanically connected to the braking operation member, an output rod which presses pistons in the master cylinder and which is linearly movable in parallel with a central axis of the input rod, a differential mechanism which receives output from the first and second electric motors, is allowed to relatively move between the input rod and the output rod, and is built in the case member, and a controller which controls the output from the first electric motor and the output from the second electric motor to independently control force acting on the input rod and displacement of the output rod.

An electro-hydraulic motor vehicle brake system is provided, having a first cylinder-piston device, which can be fluidically coupled to at least one wheel brake of the brake system, for generating hydraulic pressure on the at least one wheel brake, wherein the first cylinder-piston device comprises at least one first piston. The brake system further has a second cylinder-piston device, which comprises at least one second piston, and an electromechanical actuator which acts on the second piston of the second cylinder-piston device. The second cylinder-piston device is or can be fluidically coupled at the output side to the first piston of the first cylinder-piston device in order to provide a hydraulic pressure, which is generated in the second cylinder-piston device upon actuation of the electromechanical actuator, for actuating the at least one first piston of the first cylinder-piston device.

The vehicle braking device performs a control which makes an actual value of physical quantity associated with a braking force follow a target value thereof when the actual value is outside a dead zone and a control which suppresses a change of the actual value when the actual value is within the dead zone and includes a judging portion which judges whether or not the actual value passes through the dead zone with a value beyond the upper limit threshold value and a setting portion which sets a second upper limit threshold value more closely approximated than a first upper limit threshold value when the actual value is judged not to pass through the dead zone, as the upper limit threshold value, when the actual value is judged to pass through the dead zone by the judging portion.

The invention relates to a brake device and a method for operating a brake device, wherein said brake device comprises an actuation device, also a booster device, in particular having an electro-hydraulic drive, a piston cylinder device (main cylinder) in order to supply hydraulic pressure medium to the brake circuits, a valve device for controlling or regulating the supply of the pressure medium and an electronic control or regulating device (ECU). According to the invention provision is made for additional pressure medium volume to be supplied in a controlled manner to at least one brake circuit by means of a further piston cylinder device, in particular a double stroke piston (10) and at least one valve (AS) controlled by the control or regulating device (ECU).

A brake booster for a brake master cylinder including a drive motor connected via a linkage to a pressure piston for the brake master cylinder, the linkage having a rotatable spindle nut having an internal thread and a nonrotatable, axially displaceable spindle rod having an external thread, the threads interengaging to convert a rotational motion of the drive motor into a translational motion of the spindle rod in order to displace the pressure piston. The spindle nut has an external tooth set that is in engagement with an internal tooth set of a annular drive gear of the linkage. The spindle nut is axially displaceable with respect to the annular drive gear. Except for a first tooth flank of a tooth, which extends in a first axial portion in its longitudinal extent toward an oppositely located tooth flank, tooth flanks of the internal and external tooth sets extend axially.

A braking device for a vehicle includes a friction brake device, a regeneration bake device, a control portion which controls the friction braking force and the regeneration braking force through a cooperative control and a state judging portion which judges whether a vehicle state is in a stopped state or a non-braking operation state where the braking operation is not performed, The control portion executes a factor change control which suppresses an increase of change inclination of the friction braking force by changing a factor relating to a friction used when the hydraulic pressure is converted into the friction braking force to an increasing side and returns the factor to a value at a non-operation of the factor change control when the vehicle state is judged to be in the stopped state or the non-braking operation state by the state judging portion.

A hydraulic control device for at least one hydraulic aggregate of a brake system, and a brake booster control device, interacting therewith, for an electromechanical brake booster of the brake system. The hydraulic control device includes a first control electronics by which at least one motor target quantity that is to be realized by a motor of the electromechanical brake booster can be determined, taking into account a provided brake actuating strength quantity relating to a current actuation of a brake actuating element, and by which a specification signal corresponding to the at least one determined motor target quantity can be outputted to the brake booster control device. The brake booster control device has a second control electronics that, at least in a normal mode, outputs the control signal to the motor of the electromechanical brake booster, taking into account the specification signal outputted by the hydraulic control device.

A second ECU determines whether or not there is an abnormality in a hydraulic-pressure sensor in a first cycle based on a detection value of the hydraulic-pressure sensor, and outputs a signal indicating a determination of an occurrence of the abnormality to a first ECU via a signal line when determining the occurrence of the abnormality in the hydraulic-pressure sensor. The first ECU receives the detection value of the hydraulic-pressure sensor through communication from the second ECU via the signal line to determine whether or not there is the abnormality in the hydraulic-pressure sensor in a second cycle that is shorter than the first cycle. When determining that the hydraulic-pressure sensor is abnormal, the first ECU controls driving of an electric actuator based on a braking command from an operation-amount detection sensor without using the detection value of the hydraulic-pressure sensor determined to be abnormal.

A vehicle control device which is applicable to a vehicle brake device, controls the pressure increasing control valve and the pressure-decreasing control valve so that an actual servo pressure detected by the servo pressure sensor becomes a target servo pressure; and controls so as to increase the target servo pressure by a predetermined amount, while the brake actuator is executing the braking control which accompanies a brake fluid pumping back control wherein the brake fluid supplied to the wheel cylinder is pumped back to the master cylinder by the built-in pump.