An electric brake booster is equipped with a pressure balance detecting device, which generates braking force. The electric brake booster includes: a first pressure device, which generates pressure as the driver manipulates the brake pedal; a second pressure device, which generates the same pressure as the first pressure device and generates driving power; a master chamber, which receives resultant force of brake pedal effort and driving power of a motor from a master piston that moves in the second pressure device; and a pressure balance detecting device, which detects whether a predetermined ratio is maintained between the pressure of the first pressure device applied to one side of the pressure balance detecting device and the pressure of the master chamber applied to the other side of the pressure balance detecting device.

An electric brake booster for an autonomous vehicle is provided. The electric brake booster includes a body part that receives a power cylinder generating braking pressure in an autonomous driving/braking mode and a master cylinder generating braking pressure in a manual driver braking mode. A driving shaft is movable in an axial direction in the power cylinder and coupled to a piston. A first motor is connected to a first side of the driving shaft and provides driving power thereto. A second motor is connected to a second side of the driving shaft and provides driving power thereto in a direction equal to that of the driving power provided from the first motor. A controller determines whether the first or second motor normally operates and simultaneously or separately operates the first and second motors based on a magnitude of the pressure in the power cylinder or whether emergency braking occurs.

A pressure generating device may comprise a piston-cylinder unit having a bilaterally acting piston with two effective surfaces defining two respective, separate working spaces in a sealing manner. Each working space is connected via a hydraulic line to a hydraulic circuit, wherein at least one hydraulic chamber of a consumer is connected to each hydraulic circuit, and wherein a drive drives the piston. Each working space may be in communication with a reservoir for hydraulic medium, via a respective hydraulic line having a respective switching valve. Alternatively, one or both working spaces may be in communication with a reservoir for hydraulic medium via a hydraulic line, with a switching valve in one or both hydraulic lines, and/or a respective outlet valve may be associated with one or more hydraulic chambers of the consumer, and a further connecting line having a switching valve may connect the pressure chambers and/or hydraulic lines.

An electric brake booster for an autonomous vehicle is provided. The electric brake booster includes a body part that receives a power cylinder generating braking pressure in an autonomous driving/braking mode and a master cylinder generating braking pressure in a manual driver braking mode. A driving shaft is movable in an axial direction in the power cylinder and coupled to a piston. A first motor is connected to a first side of the driving shaft and provides driving power thereto. A second motor is connected to a second side of the driving shaft and provides driving power thereto in a direction equal to that of the driving power provided from the first motor. A controller determines whether the first or second motor normally operates and simultaneously or separately operates the first and second motors based on a magnitude of the pressure in the power cylinder or whether emergency braking occurs.

A diagnostic method to identify a leak in simulator valve in a vehicle brake system includes the steps of: (1) providing a simulator partially filled with a pressure medium and a de-energized simulator valve; (2) energizing a pumping valve, a secondary three-way valve, and a plurality of apply valves; (3) applying and retracting a plunger in a plunger assembly at least two cycles so that a predetermined pressure is achieved; (3) holding a plunger in position within the plunger assembly while maintaining a replenishing check valve in a closed/de-energized position and energizing the simulator valve; (4) obtaining a measured master cylinder secondary pressure decay; (5) comparing the measured master cylinder secondary pressure decay to a predetermined pressure decay value; and (7) identifying a leak in the simulator valve if the measured master cylinder secondary pressure decay does not match the predetermined master cylinder secondary pressure decay.

An electromechanical brake booster for a braking system of a vehicle. The brake booster includes a spindle nut that is movable into rotation using an electric motor that is intrinsic or external to the brake booster, a spindle situated at the spindle nut and rotatably fixedly held using a support plate in such a way that the spindle and the support plate are movable into pure translatory motion using the spindle nut that is moved into rotation, and a reaction disk receiving element that is also movable using the support plate that is moved into pure translatory motion. The reaction disk receiving element includes a receiving opening in which a reaction disk is situated. The support plate and the reaction disk receiving element are designed as a one-piece component. A method for manufacturing an electromechanical brake booster for a braking system of a vehicle, is also described.

A diagnostic method to identify a leak in a simulator valve for a vehicle brake system comprising the steps of: (1) energizing a secondary three-way valve, a pumping valve, a simulator test valve, and a plurality of apply valves in order to maintain a pressure medium from a plunger assembly within a boost circuit; (2) applying a plunger in the plunger assembly to a predetermined pressure level; (3) holding the plunger in position within the plunger assembly; and (4) identifying a leak in a simulator valve via a signal from an ECU to a vehicle user interface if the pressure in the boost circuit deteriorates at or more than a pre-determined rate.

A braking device includes a stroke simulator, a hydraulic pressure generation unit, a reaction hydraulic pressure detection unit, a master hydraulic pressure detection unit, and a bottoming determination unit. The stroke simulator includes a cylinder and a piston slidably movable inside the cylinder in conjunction with an operation of a brake operation member. The stroke simulator causes a reaction force chamber to generate a reaction hydraulic pressure and applies a reaction force. The hydraulic pressure generation unit generates a master hydraulic pressure by driving a master piston and supplies a hydraulic pressure to a wheel cylinder. The reaction hydraulic pressure detection unit detects the reaction hydraulic pressure. The master hydraulic pressure detection unit detects the master hydraulic pressure. The bottoming determination unit determines whether the master piston is in a bottoming state based on the reaction hydraulic pressure and the master hydraulic pressure.

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. 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 and at least one valve controlled by the control or regulating device.

A pressure generating device may comprise a piston-cylinder unit having a bilaterally acting piston with two effective surfaces defining two respective, separate working spaces in a sealing manner. Each working space is connected via a hydraulic line to a hydraulic circuit, wherein at least one hydraulic chamber of a consumer is connected to each hydraulic circuit, and wherein a drive drives the piston. Each working space may be in communication with a reservoir for hydraulic medium, via a respective hydraulic line having a respective switching valve. Alternatively, one or both working spaces may be in communication with a reservoir for hydraulic medium via a hydraulic line, with a switching valve in one or both hydraulic lines, and/or a respective outlet valve may be associated with one or more hydraulic chambers of the consumer, and a further connecting line having a switching valve may connect the pressure chambers and/or hydraulic lines.