A brake system comprises a reservoir; a brake pedal; a master cylinder including a first master chamber, a second master chamber, a first master piston, and a second master piston; a first hydraulic circuit including at least one first hydraulic wheel brake; a second hydraulic circuit including at least one second hydraulic wheel brake; and a hydraulic pressure supplier including an actuator for pressurizing the first hydraulic circuit and the second hydraulic circuit depending on an operation of the brake pedal in a normal operating mode. The master cylinder further comprises a locking chamber and an elastic pedal feel element arranged in the first master chamber to be in contact with the first master piston and the second master piston for generating a pedal force when the brake pedal is operated while the second master piston is locked in the normal operating mode.

A brake system comprises a reservoir; a brake pedal; a master cylinder including a first master chamber, a second master chamber, a first master piston, and a second master piston; a first hydraulic circuit including at least one first hydraulic wheel brake; a second hydraulic circuit including at least one second hydraulic wheel brake; and a hydraulic pressure supplier including an actuator for pressurizing the first hydraulic circuit and the second hydraulic circuit depending on an operation of the brake pedal in a normal operating mode. The master cylinder further comprises a locking chamber and an elastic pedal feel element arranged in the first master chamber to be in contact with the first master piston and the second master piston for generating a pedal force when the brake pedal is operated while the second master piston is locked in the normal operating mode.

Provided is a brake apparatus, a brake control method, and a method for determining a lock abnormality in a motor capable of reducing motor drive noise at the time of a self-diagnosis of the motor regardless of a condition. A brake control method includes issuing a drive instruction to repeat ON/OFF driving a plurality of times and drive a motor in such a manner that a rotational frequency of the motor during an OFF time period does not fall to zero and a peak of the rotational frequency of the motor during an ON time period increases as the ON/OFF driving is repeated, carrying out terminal voltage detection to detect a terminal voltage of the motor at the time of the ON/OFF driving carried out by the issuing of the drive instruction, and determining a lock abnormality in the motor to determine whether there is the lock abnormality in the motor based on a characteristic of the terminal voltage during the OFF time period of the ON/OFF driving that is detected by the carrying out of the terminal voltage detection.

Provided is a brake apparatus, a brake control method, and a method for determining a lock abnormality in a motor capable of reducing motor drive noise at the time of a self-diagnosis of the motor regardless of a condition. A brake control method includes issuing a drive instruction to repeat ON/OFF driving a plurality of times and drive a motor in such a manner that a rotational frequency of the motor during an OFF time period does not fall to zero and a peak of the rotational frequency of the motor during an ON time period increases as the ON/OFF driving is repeated, carrying out terminal voltage detection to detect a terminal voltage of the motor at the time of the ON/OFF driving carried out by the issuing of the drive instruction, and determining a lock abnormality in the motor to determine whether there is the lock abnormality in the motor based on a characteristic of the terminal voltage during the OFF time period of the ON/OFF driving that is detected by the carrying out of the terminal voltage detection.

An electropneumatic rail brake system configured to provide emergency braking including an emergency magnet valve which controls air flow into an emergency regulator valve, which valve has an emergency back-up chamber. The emergency regulator provides an output pressure nominally equal to the variable load pressure and no lower than the tare back-up. The magnet valve is closed when energized and when de-energized, pressure is allowed into the emergency back-up chamber, Regulation of the brake cylinder pressure continues during an emergency application such that the brake cylinder pressure applied during an emergency stop does not drop below a predetermined level. In the event of power-loss during an emergency brake stop, the nominal emergency brake pressure is applied to the brake cylinders.

An electropneumatic rail brake system configured to provide emergency braking including an emergency magnet valve which controls air flow into an emergency regulator valve, which valve has an emergency back-up chamber. The emergency regulator provides an output pressure nominally equal to the variable load pressure and no lower than the tare back-up. The magnet valve is closed when energized and when de-energized, pressure is allowed into the emergency back-up chamber, Regulation of the brake cylinder pressure continues during an emergency application such that the brake cylinder pressure applied during an emergency stop does not drop below a predetermined level. In the event of power-loss during an emergency brake stop, the nominal emergency brake pressure is applied to the brake cylinders.

A brake system for a vehicle may include at least two hydraulic brake circuits, each having at least one hydraulically acting wheel brake, at least two pressure supply devices, each of which is driven by an electromotive drive, at least one valve assembly having valves for the wheel-individual adjustment of brake pressures and/or for separating the wheel brakes from, or connecting same to, a pressure supply device, at least one electronic control and regulating unit, one of which is a superordinate central control unit that controls individual control and regulating units of the components of the brake system, as well as at least one additional electric drive motor for at least one axle or wheel of the vehicle. The brake system may use the at least one pressure supply device and/or the at least one electric drive motor for controlling pressure in at least one wheel brake for steering interventions.

A brake system for a vehicle may include at least two hydraulic brake circuits, each having at least one hydraulically acting wheel brake, at least two pressure supply devices, each of which is driven by an electromotive drive, at least one valve assembly having valves for the wheel-individual adjustment of brake pressures and/or for separating the wheel brakes from, or connecting same to, a pressure supply device, at least one electronic control and regulating unit, one of which is a superordinate central control unit that controls individual control and regulating units of the components of the brake system, as well as at least one additional electric drive motor for at least one axle or wheel of the vehicle. The brake system may use the at least one pressure supply device and/or the at least one electric drive motor for controlling pressure in at least one wheel brake for steering interventions.

A vehicle brake system, including: a first hydraulic-pressure control mechanism and a second hydraulic-pressure control mechanism configured to control a braking force; and a controller including a first-abnormal-state detecting device configured to detect whether the first hydraulic-pressure control mechanism is in a first abnormal state, a second-abnormal-state detecting device configured to detect whether the first hydraulic-pressure control mechanism is in a second abnormal state that the first hydraulic-pressure control mechanism reaches before reaching the first abnormal state, and an assist control device configured to control the second braking-force control mechanism so as to control the braking force when an assist wait time elapses after the second-abnormal-state detecting device has detected that the first hydraulic-pressure control mechanism is in the second abnormal state, the assist wait time being determined based on a temperature of a working fluid obtained by a temperature obtaining device of the brake system.

A vehicle brake system, including: a first hydraulic-pressure control mechanism and a second hydraulic-pressure control mechanism configured to control a braking force; and a controller including a first-abnormal-state detecting device configured to detect whether the first hydraulic-pressure control mechanism is in a first abnormal state, a second-abnormal-state detecting device configured to detect whether the first hydraulic-pressure control mechanism is in a second abnormal state that the first hydraulic-pressure control mechanism reaches before reaching the first abnormal state, and an assist control device configured to control the second braking-force control mechanism so as to control the braking force when an assist wait time elapses after the second-abnormal-state detecting device has detected that the first hydraulic-pressure control mechanism is in the second abnormal state, the assist wait time being determined based on a temperature of a working fluid obtained by a temperature obtaining device of the brake system.