Vehicle ABS braking system

摘要

An ABS braking system has at least one return delivery pump and for each wheel cylinder at least one two-position solenoid valve. In one position, pressure build-up is allowed, and in the other position when the pump is running, pressure reduction is allowed. The valve is controlled by pulses at a preset frequency and a preset mark-space ratio so that the pressure in the wheel cylinder varies about a preset mean pressure. The frequency is chosen to give a particular amplitude of this variation. It is preferably between 30 and 100 Hertz. The mark-space ration is chosen to give a particular mean pressure and is preferably between 0.5 and 0.9.