A method for operating an electromechanical braking system for a transportation vehicle having a brake pedal, a brake master cylinder, and an electromechanical brake booster. The electromechanical brake booster includes an actuator motor for increasing or decreasing the pedal force on the brake master cylinder to boost or reduce the braking power accordingly. A change in the boosting force of the electromechanical brake booster is limited to avoid uncontrolled changes of the brake boosting.

An actuator assembly for an integrated dynamic brake apparatus according to an embodiment of the present invention includes a hollow motor having a stator and a rotor spaced apart from an inner circumferential surface of the stator; a block having one side coupled to one side of the motor and in which chamber that accommodates fluid is formed; a gear unit having one side coupled and fixed to the rotor to convert rotational movement of the rotor to linear movement; a piston configured to receive the converted linear movement from the gear unit to linearly reciprocate; and an electronic control unit coupled to the other side of the block and comprising a motor position sensor configured to detect a position of the motor.

A vehicle braking device includes: an electric cylinder in which a piston driven by an electric motor slides in a cylinder to supply fluid; a hydraulic pressure output unit connected to the electric cylinder by way of a first liquid passage, the hydraulic pressure output unit pressurizing or depressurizing a hydraulic pressure in the first liquid passage and outputting the hydraulic pressure to a supply liquid passage connected to a first wheel cylinder; and a control unit that causes at least one of the electric cylinder and the hydraulic pressure output unit to generate the hydraulic pressure in the first wheel cylinder according to a relative position between the piston and the cylinder.

The present disclosure provides an electronic hydraulic brake system that can appropriately provide redundancy braking force, that is, an electronic hydraulic brake system that provides a so-called redundancy function, in the situation in which a driver does not drive or gives less attention to driving such as autonomous driving or smart cruise control and a main braking device malfunctions.

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 vehicle braking system (20) has a primary braking unit (22) with a first pressure generating unit (34) and a first reservoir (26). The vehicle braking system (20) further has a secondary braking unit (24) with a second pressure generating unit (52) and second reservoir (70). A method of operating the vehicle braking system (20) includes actuating the pressure generating unit (34) of the primary braking unit (22) thereby pressurizing a fluid at a wheel cylinder (30) to slow or stop the vehicle. The wheel cylinder (30) is depressurized in response to an electrical signal provided to an electronic control unit (100,102). The fluid is transferred from the wheel cylinder (30) to the second reservoir (70). The fluid path (PI) between the wheel cylinder (30) and the second reservoir (70) is shorter and has less fluid resistance than the fluid path (P2) between the wheel cylinder (30) and the first reservoir (26). The present invention further comprises two braking systems. The present inventions are intended for fast pressure depressurization at quick start or launch control.

A brake pedal unit includes a housing defining a bore formed therein. An input piston is slidably disposed in the bore. The input piston is connected to a brake pedal such that engagement of the brake pedal causes movement of the input piston within the bore of the housing of the brake pedal unit. The brake pedal unit is defined to be in an at rest position when the brake pedal in not engaged causing movement of the input piston. A primary piston is slidably disposed in the bore for pressurizing a primary chamber. A primary passageway permits fluid communication between the primary chamber and the reservoir, wherein fluid flow through the primary passageway is blocked when the brake pedal unit is in the rest position. A secondary piston is slidably disposed in the bore for pressurizing a secondary chamber. A secondary passageway permits fluid communication between the secondary chamber and the reservoir, wherein fluid flow through the secondary passageway is blocked when the brake pedal unit is in the rest position.

In a method for controlling a hydraulic brake system in a vehicle, wherein the hydraulic brake system is equipped with a hydraulic pump, the hydraulic pump is activated to hold the vehicle at rest and brake fluid is conveyed via open inlet valves to the wheel braking device of a first vehicle axle. The inlet valves on wheel braking devices of a second vehicle axle are at least partially open in response to a change in the brake pressure requirement in the brake system, and at the same time the outlet valves on said wheel braking devices remain closed while the vehicle is being held at rest.

A vehicle braking system includes a master cylinder. In a delivery line of the master cylinder there is a pressure transfer device, which generates a pressure in a hydraulic actuating line of a respective brake device following a fluid pressure communicated to a first inlet of the pressure transfer device from the delivery line and/or following a fluid pressure supplied to a second inlet of the pressure transfer device from an electrically-operated fluid pressure source. An electronic controller controls an enabling/disabling solenoid valve, and the electrically-operated fluid pressure source to create different operating modes of the system. The system does not include any vacuum-operated servo-assisting devices. The master cylinder is associated with a hydraulic device for adjusting the feeling on the brake pedal, in which a fluid pressure is generated that opposes the brake pedal actuation. The electronic controller controls the pressure in the device for adjustment of the feeling on the pedal.

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.