Patent ID: 8827379

Claim:
A hydraulic brake unit, comprising: a manual hydraulic pressure supply unit that pressurizes a hydraulic medium supplied from a reservoir storing the hydraulic medium and generates a hydraulic pressure corresponding to a brake operation amount generated by a driver; a first hydraulic system that includes a first cut valve and in which the manual hydraulic pressure supply unit communicates with a first wheel cylinder so that the hydraulic pressure generated by the manual hydraulic pressure supply unit is transmitted to the first wheel cylinder; a second hydraulic system that includes a second cut valve and in which the manual hydraulic pressure supply unit communicates with a second wheel cylinder so that the hydraulic pressure generated by the manual hydraulic pressure supply unit is transmitted to the second wheel cylinder; a separation valve that is provided in a main flow passage connecting the first hydraulic system to the second hydraulic system; and a brake ECU that includes: a separation valve control unit that open/close controls the separation valve, a hydraulic medium amount detection unit that detects whether or not the hydraulic medium stored in the reservoir has decreased below a predetermined amount, a cut valve control unit that blocks the hydraulic medium by closing either the first cut valve or the second cut valve, a faulty system determination unit that determines whether faults occur in the first hydraulic system or the second hydraulic system, wherein each of the first cut valve and the second cut valve opens and blocks flow of the hydraulic medium, wherein the separation valve control unit closes the separation valve when the hydraulic medium amount detection unit detects that the hydraulic medium has decreased below the predetermined amount, wherein the separation valve control unit closes the separation valve when a state in which the hydraulic medium amount detection unit detects that the hydraulic medium has decreased below the predetermined amount continues for a predetermined reduction detection time, wherein the cut valve control unit closes the first cut valve or the second cut valve to block the hydraulic medium when the separation valve control unit closes the separation valve, wherein the faulty system determination unit determines a fault in the first hydraulic system or the second hydraulic system that corresponds to the first cut valve or the second cut valve that is not closed has occurred when the first cut valve or the second cut valve is closed and a continued reduction in the hydraulic medium is detected by the hydraulic medium amount detection unit, and wherein the faulty system determination unit determines a fault in the first hydraulic system or the second hydraulic system that corresponds to the first cut valve or the second cut valve that is closed has occurred when the first cut valve or the second cut valve is closed and the continued reduction is not detected by the hydraulic medium amount detection unit.