초록 ▼

A mechanical pressurization device is connected to a common passage, and brake cylinders provided respectively for front left and right and rear left and right wheels are connected to the common passage respectively via pressure holding valves. Each of the pressure holding valves in the front is a n

A mechanical pressurization device is connected to a common passage, and brake cylinders provided respectively for front left and right and rear left and right wheels are connected to the common passage respectively via pressure holding valves. Each of the pressure holding valves in the front is a normally open valve, and each of the pressure holding valves in the rear is a normally closed valve. In the event of an abnormality in which a hydraulic pressure in the common passage cannot be controlled using a hydraulic pressure produced by a power hydraulic pressure source, a hydraulic pressure in the mechanical pressurization device is supplied to the front brake cylinders provided respectively for the front left and right wheels.

대표청구항 ▼

1. A hydraulic brake system comprising: a plurality of hydraulic brakes provided respectively for front left, front right, rear left and rear right wheels of a vehicle, and each of the plurality of hydraulic brakes being configured to operate by a hydraulic pressure in a corresponding one of a plura

1. A hydraulic brake system comprising: a plurality of hydraulic brakes provided respectively for front left, front right, rear left and rear right wheels of a vehicle, and each of the plurality of hydraulic brakes being configured to operate by a hydraulic pressure in a corresponding one of a plurality of brake cylinders to restrain rotation of a corresponding one of the front left, front right, rear left and rear right wheels of the vehicle;a power hydraulic pressure source configured to produce a hydraulic pressure by supply of electric energy;at least one manual hydraulic pressure source configured to produce a hydraulic pressure by a braking operation of a driver;a pressurization device configured to operate by at least a hydraulic pressure produced by one manual hydraulic pressure source of the at least one manual hydraulic pressure source, the pressurization device being capable of outputting a hydraulic pressure that is greater than the hydraulic pressure produced by the one manual hydraulic pressure source of the at least one manual hydraulic pressure source;a common passage to which the pressurization device and the power hydraulic pressure source are connected and to which the plurality of brake cylinders respectively provided for the front left, front right, rear left and rear right wheels are connected;a power hydraulic-pressure control device configured to control a hydraulic pressure in the common passage by utilizing the hydraulic pressure produced by the power hydraulic pressure source; andan abnormal-case servo-pressure supply device configured to, when the power hydraulic-pressure control device cannot control the hydraulic pressure in the common passage, supply a servo pressure to brake cylinders provided respectively for at least two wheels comprising front left and front right wheels of the front left, front right, rear left and rear right wheels, wherein the servo pressure is an output hydraulic pressure provided by the pressurization device, wherein:the pressurization device comprises: (i) an outer-circumferential-side cylindrical portion and an inner-circumferential-side cylindrical portion arranged one inside of the other, and (ii) a hydraulic-pressure control valve configured to couple and decouple a control-pressure port connected to the common passage and a high pressure port coupled to the power hydraulic pressure source to and from each other by relative movement of the outer-circumferential-side cylindrical portion and the inner-circumferential-side cylindrical portion in an axial direction thereof, anda first one of the outer-circumferential-side cylindrical portion and the inner-circumferential-side cylindrical portion is moveable in the axial direction by the hydraulic pressure produced by the manual hydraulic pressure source, and a second one of the outer-circumferential-side cylindrical portion and the inner-circumferential-side cylindrical portion is moveable in the axial direction by a motive force produced by a solenoid. 2. The hydraulic brake system according to claim 1, wherein the abnormal-case servo-pressure supply device includes a three-wheel supplier configured to supply the servo pressure provided by the pressurization device to brake cylinders provided respectively for three wheels including the front left and right wheels. 3. The hydraulic brake system according to claim 1, further comprising: two manual hydraulic pressure sources each as the manual hydraulic pressure source; anda manual-hydraulic-pressure and power-control-pressure supplier configured to, when there is a possibility of fluid leakage in the hydraulic brake system, decouple the brake cylinders provided for the respective front left and right wheels from the common passage, couple the brake cylinders provided for the respective front left and right wheels respectively to the two manual hydraulic pressure sources, and supply a hydraulic pressure controlled by power hydraulic-pressure control device to the brake cylinders provided for the respective rear left and right wheels. 4. The hydraulic brake system according to claim 1, wherein the brake cylinders respectively provided for the four wheels are connected to the common passage respectively via the four individual brake-side passages in which at least four individual control valves are respectively provided, andeach of the at least four individual control valves respectively corresponds to at least two brake cylinders, the at least two brake cylinders including the brake cylinders provided for the respective front left and front right wheels, and at least one of the at least four individual control valves is a normally open valve. 5. The hydraulic brake system according to claim 1, wherein the brake cylinders respectively provided for the four wheels are connected to the common passage respectively via the four individual brake-side passages in which at least four individual control valves are respectively provided, andeach of the at least four individual control valves respectively corresponds to at least two brake cylinders, the at least one brake cylinder provided for at least one of the rear left and rear right wheels, and at least one of the at least four individual control valves is a normally closed valve. 6. The hydraulic brake system according to claim 1, wherein the pressurization device is connected to the common passage via an output-side cut-off valve that is a normally open valve. 7. The hydraulic brake system according to claim 1, further comprising a hydraulic-pressure controller configured to, in a normal condition, isolate the pressurization device from the common passage and control the hydraulic pressure produced by the power hydraulic pressure source to control the hydraulic pressure in the common passage. 8. The hydraulic brake system according to claim 1, wherein the power hydraulic pressure source includes: (a) a pump device, and(b) an accumulator configured to store a hydraulic pressure ejected from the pump device.