A brake system for a vehicle having a master brake cylinder, which provides a pressure signal, having a brake-medium reservoir connected to the master brake cylinder, and a first brake circuit, which is coupled by a first input to the master brake cylinder and by a second input to the brake-medium reservoir, and having at least one first wheel brake cylinder, which is mounted at a first wheel, in order to exert a force corresponding to the pressure signal onto the first wheel, and having a separator valve, which is configured between the first input and the first wheel-brake cylinder, to prevent further transmission of the pressure signal upon receipt of a supplied closing signal; and having a control valve, which is configured between the first input and the first wheel-brake cylinder; in order to control an inflow of a brake medium from brake-medium reservoir to the first wheel-brake cylinder. In addition, a method for controlling a corresponding brake system is also described.

The present disclosure relates to a master cylinder and an electronic brake system having the same. The master cylinder includes a cylinder block having a bore of a multi-stage form in a longitudinal direction therein, a first master chamber and a second master chamber sequentially arranged in series in the bore, a first master piston provided to move in connection with an operation of a brake pedal and to pressurize the first master chamber, a second master piston provided to be displaceable by a displacement of the first master piston or a hydraulic pressure in the first master chamber and to pressurize the second master chamber, and a pedal simulator interposed between the first master piston and the second master piston to provide a reaction force to the brake pedal, wherein a cross-sectional area of the first master piston is provided to be relatively larger than a cross-sectional area of the second master piston.

The braking control device for a vehicle is adapted to be used for a vehicle brake device and it is an object of the present invention to prevent an operator of the vehicle from feeling of any an unpleasant feeling by reducing an ineffective operating amount by which no braking force increases in response to the increase of the brake operating amount. The braking control device includes a controlling portion for changing a servo performance to an ineffective operating amount reducing servo performance which is closer to the increase ratio of the hydraulic pressure braking force relative to the increase of the brake operating amount after the input piston has been in contact with the output piston when the brake operating amount reaches to the servo performance change operating amount which is smaller than the assisting limit operating amount.

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 brake system may include an actuation device that may actuate a first piston-cylinder unit to apply pressure medium to at least one brake circuit via a valve device, where a piston of the first piston-cylinder unit separate first and second working chambers; a second piston-cylinder unit, having an electromotive drive and a transmission to feed pressure medium to at least one of the brake circuits via a valve device; and a motor-pump unit having a valve device to feed pressure medium to the brake circuits. The motor of the electromotive drive of the second piston-cylinder unit and the motor of the motor-pump unit may be used jointly or independently of one another, under control of a control device. The motor-pump unit is connected via two hydraulic connections, one or both of which may incorporate separating valves, to the first and second working chambers of the first piston-cylinder unit.

A brake system may include an actuation device that may actuate a first piston-cylinder unit to apply pressure medium to at least one brake circuit via a valve device, where a piston of the first piston-cylinder unit separate first and second working chambers; a second piston-cylinder unit, having an electromotive drive and a transmission to feed pressure medium to at least one of the brake circuits via a valve device; and a motor-pump unit having a valve device to feed pressure medium to the brake circuits. The motor of the electromotive drive of the second piston-cylinder unit and the motor of the motor-pump unit may be used jointly or independently of one another, under control of a control device. The motor-pump unit is connected via two hydraulic connections, one or both of which may incorporate separating valves, to the first and second working chambers of the first piston-cylinder unit.

A brake booster device. The brake booster includes a reservoir and a master brake cylinder having at least one chamber and at least one piston arranged in the chamber. The chamber can be connected to the pressure regulator so that the piston can be at least partially by returned via the pressure regulator, wherein the chamber can be connected to the reservoir, wherein a valve is arranged between the chamber and the reservoir.

An accumulator assembly includes a medium pressure accumulator having an MPA cavity including at least one brake-side passage adjacent a first end thereof. A powered MPA two-way valve is interposed fluidically between the brake-side passage of the MPA cavity and at least one corresponding wheel brake. The MPA two-way valve includes an MPA two-way valve cavity placing the brake-side passage of the MPA cavity and the at least one corresponding wheel brake in selective fluid communication via both of an MPA two-way valve fill fluid path configured to provide pressurized hydraulic fluid to the MPA cavity and an MPA two-way valve supply fluid path configured to remove pressurized hydraulic fluid from the MPA cavity.

An accumulator assembly includes a medium pressure accumulator, having an MPA cavity including a brake-side passage and a pump-side passage. A nonpowered MPA fill valve is interposed fluidically between the pump-side passage of the MPA cavity and a source of pressurized hydraulic fluid. An MPA fill valve seat is located along an MPA fill valve fluid path. An MPA fill valve poppet is configured for reciprocal motion between a poppet rest position and a poppet closed position wherein an MPA fill valve poppet shoulder contacts the MPA fill valve seat to occlude fluid flow therepast. A powered MPA one-way valve is interposed fluidically between the brake-side passage and at least one corresponding wheel brake.

A brake system includes a reservoir and a motor-driven master cylinder operable during a backup braking mode by actuation of an electric motor of the master cylinder to generate brake actuating pressure for hydraulically actuating the pair of front wheel brakes and the pair of rear wheel brakes. A power transmission unit is configured for selectively providing pressurized hydraulic fluid to a PTU output for actuating the pair of front wheel brakes and the pair of rear wheel brakes in a normal non-failure braking mode. First and second two-position three-way valves are each hydraulically connected with the master cylinder, the power transmission unit, and a selected pair of the front and rear wheel brakes. Each of the first and second three-way valves selectively controls hydraulic fluid flow from a chosen one of the master cylinder and the power transmission unit to the selected pair of front and rear wheel brakes.