Combined antiskid and traction control electronic brake system

摘要

A brake system capable of implementing anti-skid and traction control operations has an electromagnetic valve for connecting a master cylinder to a wheel cylinder and for disconnecting the master cylinder from the wheel cylinder when anti-skid or traction control is executed. A piezo-electric hydraulic pump is provided for introducing high-pressure brake oil when anti-skid or traction control is executed. A pressure reduction valve selectively introduces and removes brake oil so that a desired wheel cylinder pressure can be attained when anti-skid or traction control is executed. A hydraulic switching valve is connected to the main oil pressure line parallel to the electromagnetic valve and allows pressure in the master cylinder to be opened to the wheel cylinder during a braking operation. The system also includes a unit for establishing one-way communication from the wheel cylinder to the master cylinder during anti-skid control to prevent pressure in the wheel cylinder from being higher than that in the master cylinder while preventing connection between the master cylinder and the wheel cylinder during traction control.