Vehicle brake installations

Claim 1

Brake installation for a vehicle with an internal combustion engine, comprising brakes actuated by the movements of a piston member in a master cylinder, which movements themselves are controllable by thrust on a brake pedal connected to said piston member by an assistance mechanism of the vacuum ''''servobrake'''' type, said mechanism comprising: a fixed casing divided into two compartments A and B by piston means connected to said piston member, pipe means for applying in said compartment A, furthest spaced from the brake pedal, the suction which exists at a suitable point of said engine, first valve means controlled by the brake pedal, first passage means connecting compartment A to said first valve means, second passage means connecting said first valve means to compartment B, third passage means connecting said first valve means to the atmosphere, said first valve means transmitting the same suction in compartment A to compartment B as long as said pedal is released and reducing this sucction automatically when the pedal is relatively depressed, by connecting said compartment B with the atmosphere through said third passage means, said installation including: duct means leading from compartment B to the atmosphere, second valve means comprising a simple stop valve inserted in said duct means and control means other than said brake pedal arranged to regulate the action of said stop valve and including assistance mechanism comprising a further valve mounted on said second passage means, which further valve is adapted to be tranversed by a relatively high air-flow towards compartment B and by a relatively low airflow towards compartment A.