초록 ▼

A brake control system for an automotive vehicle has an improved hydraulic circuit network which is capable of performing pressure boosting operation for a pressure supplied from a master cylinder, as well as anti-skid brake control operation and traction control operation. The system includes a val

A brake control system for an automotive vehicle has an improved hydraulic circuit network which is capable of performing pressure boosting operation for a pressure supplied from a master cylinder, as well as anti-skid brake control operation and traction control operation. The system includes a valve device for selectively establishing and blocking fluid communication between master cylinder and wheel cylinder. The valve device is generally responsive to the fluid pressure supplied from the master cylinder to enter into pressure boosting mode in response to increase in the fluid pressure from the master cylinder across a predetermined value. An electronically operable boost control device cooperates with the valve device for varying pressure boosting magnitude depending upon vehicle driving condition. An electronically operable traction control device is also provided and cooperates with the boost control device for generating a braking force to decelerate a vehicle wheel irrespectively of manual operation state of brake system when wheel spinning is detected or predicted. The system exhibits high safety level by an enhanced fail-safe function.

대표청구항 ▼

A brake control system for an automotive vehicle, comprising: a master cylinder for producing a master cylinder pressure corresponding to operational magnitude of manually operable means for operating brake; a wheel cylinder provided for each vehicle wheel for applying braking force to said wheel, s

A brake control system for an automotive vehicle, comprising: a master cylinder for producing a master cylinder pressure corresponding to operational magnitude of manually operable means for operating brake; a wheel cylinder provided for each vehicle wheel for applying braking force to said wheel, said wheel cylinder being connected to said master cylinder via a hydraulic circuit; an electronically controlled pressure control valve for generating a control pressure, said pressure control valve including an actuator for reducing pressure level of said control pressure with an increase in operational magnitude thereof, said pressure control valve being coupled with said master cylinder for introducing said master cylinder pressure into said pressure control valve pressure to increase said control pressure with an increase in said master cylinder pressure; an external fluid pressure source connected to said pressure control valve through an external pressure supply line, for supplying an external pressure at a predetermined pressure level to said pressure control valve; and a composite pressure generator valve disposed in said hydraulic circuit between said master cylinder and said wheel cylinder for selectively establishing and blocking fluid communication therebetween, said composite pressure generator valve being connected to said pressure control valve to receive said control pressure therefrom and being movable between a first valve position which allows fluid communication between said master cylinder and said wheel cylinder for supplying said master cylinder pressure to said wheel cylinder, and a second valve position in which fluid communication between said master cylinder and said wheel cylinder is blocked for forming a closed circuit across said wheel cylinder and compressing working fluid within said closed circuit to have a magnitude corresponding to the magnitude of said control pressure for establishing a boosted pressure to be applied to said wheel cylinder, which is higher than said master cylinder pressure, wherein the magnitude of said control pressure is determined by a balance of a force derived from said master cylinder pressure and a force derived from said actuator, and wherein said actuator provides a maximum force which cancels said force derived from said master cylinder pressure to maintain said control pressure at a value of zero thus, supplying pressure directly from said master cylinder to said wheel cylinder.