A brake system may include an actuation device, in particular a brake pedal; a first piston-cylinder unit with two pistons, in particular an auxiliary piston and a second piston, in order to supply brake circuits with a pressure medium via a valve device, wherein one of the pistons, in particular the auxiliary piston, can be actuated by means of the actuation device; a second piston-cylinder unit comprising an electric motor-powered drive, a transmission, and at least one piston in order to supply pressure medium to at least one of the brake circuits via a valve device; and a motor pump unit with a valve device in order to supply pressure medium to the brake circuits. The brake system may further include a hydraulic travel simulator which is connected to a pressure or working chamber of the first piston-cylinder unit.

A method is provided for operating a motor vehicle brake system that includes an actuatable brake master cylinder, a hydraulic brake booster, and at least one brake circuit that has at least one hydraulically actuatable wheel brake and at least one hydraulic-pressure generator driven by electric motor. The method includes monitoring a state of actuation of the brake master cylinder is monitored, and, upon detecting a maximum state of actuation, activating the hydraulic-pressure generator to increase the hydraulic pressure adjusted by the brake master cylinder in the brake circuit.

The present disclosure relates to a brake device for a vehicle, and a main object of the present disclosure is to provide a brake device for a vehicle which can stably perform an electric parking braking cooperative control process for dynamic parking braking in a state in which the brake device enters a backup mode due to an abnormality or a malfunction generated in a device related to an electric booster in a vehicle equipped the electric booster. In order to achieve the above object, a brake device including a fallback valve which is provided on a hydraulic pressure supply line connected to a wheel brake of a wheel on which an electronic parking brake is installed, and which is configured to selectively shut off brake liquid pressure supplied to the wheel brake, and a method for controlling the same are disclosed.

A brake system may include an actuating device, in particular a brake pedal; a first piston-cylinder unit having two pistons subjecting the brake circuits to a pressure medium via a valve device, wherein one of the pistons can be actuated by the actuation device; a second piston-cylinder unit having an electric motor drive, a transmission at least one piston to supply at least one of the brake circuits with a pressure medium via a valve device; and a motor pump unit with a valve device to supply the brake circuits with a pressure medium. The brake system may also include a hydraulic travel simulator with a pressure or working chamber which is connected to the first piston-cylinder unit.

A pedal feel emulator comprises a housing extending along a center axis between a closed end and an opened end and defining a chamber extending therebetween. A first piston is slidably disposed in the chamber. The first piston defines a compartment in fluid communication with the chamber. A second piston is slidably disposed in the compartment. A spring seat extends radially outwardly from the second piston. A first elastic member is located in the chamber extending between the spring seat and the closed end. A second elastic member is located in the compartment and extending between the spring seat and the first piston. A third elastic member is located between the second piston and the first piston. A brake system including the pedal feel emulator is also disclosed herein.

A method for checking functionality of a motor vehicle braking system. The braking system has a main module, including: hydraulically actuatable wheel brakes, pairs being assigned to respective brake circuits; at least one electrically actuatable wheel valve per wheel brake sets wheel-specific brake pressures; a pressure provision device actively builds up pressure in the wheel brakes; a pressure-medium reservoir at atmospheric pressure, and an auxiliary module, which has for each of two wheel brakes: a pressure sensor for measuring pressure in a wheel brake line; an open when deenergized isolating valve in the wheel brake line; a pump. At least one variable is measured to assess functionality of the braking system. Using least one acceptance criterion, and checked whether the variable satisfies the acceptance criterion. Determining at least one variable representing the viscosity of the brake fluid, and the at least one acceptance criterion depends on a variable representing viscosity.

A pedal feel emulator comprises a housing extending along a center axis between a closed end and an opened end and defining a chamber extending therebetween. A first piston is slidably disposed in the chamber. The first piston defines a compartment in fluid communication with the chamber. A second piston is slidably disposed in the compartment. A spring seat extends radially outwardly from the second piston. A first elastic member is located in the chamber extending between the spring seat and the closed end. A second elastic member is located in the compartment and extending between the spring seat and the first piston. A third elastic member is located between the second piston and the first piston. A brake system including the pedal feel emulator is also disclosed herein.

A brake system may include an actuating device, in particular a brake pedal; a first piston-cylinder unit having two pistons subjecting the brake circuits to a pressure medium via a valve device, wherein one of the pistons can be actuated by the actuation device; a second piston-cylinder unit having an electric motor drive, a transmission at least one piston to supply at least one of the brake circuits with a pressure medium via a valve device; and a motor pump unit with a valve device to supply the brake circuits with a pressure medium. The brake system may also include a hydraulic travel simulator with a pressure or working chamber which is connected to the first piston-cylinder unit.

Disclosed is a brake apparatus capable of minimizing the stress of valves. The brake apparatus comprises: a first wheel cylinder provided in a first wheel; a second wheel cylinder provided in a second wheel; a first outlet valve for controlling discharge of brake oil from the first wheel cylinder; a second outlet valve for controlling discharge of the brake oil from the second wheel cylinder; and a controller which opens and then closes one of the first and second outlet valves in response to a first braking command generated when a brake pedal deviates from a standard position, and opens and then closes the other outlet valve of the first and second outlet valves in response to a first brake suspending command generated when the brake pedal is restored to the standard position.

A method for operating a brake system of a motor vehicle. The brake system includes a master brake cylinder operable by a user and a pressure generator driven by an electric motor, for generating a hydraulic system pressure, and includes at least one hydraulically operable friction brake. On the inlet side, the at least one friction brake is assigned a proportioning valve acted upon by the system pressure, to adjust a hydraulic actuating pressure for the friction brake. The pressure generator is given a setpoint value for carrying out a testing operation. The setpoint value is selected so as to be smoothed by a logistical growth function.