Brake pressure proportioning device

Claim 1

A PRESSURE PROPORTIONING DEVICE ADAPTED TO BE INTERPOSED BETWEEN THE MASTER CYLINDER AND THE REAR BRAKE CYLINDERS OF THE HYDRAULIC BRAKE SYSTEM OF A VEHICLE HAVING FRONT AND REAR BRAKES, SAID DEVICE INCLUDING DIFFERENTIAL AREA PISTON MEANS, SAID PISTON MEANS HAVING AREAS EXPOSED TO FLUID FROM SAID MASTER CYLINDER, A VALVE ARRANGED FOR CLOSURE AFTER A PREDETERMINED INITIAL BRAKE APPLICATION AND OPERABLE TO LIMIT THE AREAS OF SAID PISTON EXPOSED TO MASTER CYLINDER PRESSURE, SAID PISTON MEANS HAVING AT LEAST ONE FLUID DISPLACING PORTION OPERABLE TO PRESSURIZE FLUID AT SAID REAR BRAKE CYLINDERS BY MOVEMENT THEREOF IN A GIVEN DIRECTION UPON AN INCREASE IN MASTER CYLINDER PRESSURE AFTER ACTUATION OF SAID VALVE, AND RESILIENT MEANS ARRANGED FOR LOADING BY SAID PISTON MEANS DURING A SUBSTANTIAL PORTION OF SAID INITIAL BRAKE APPLICATION AND OPERABLE TO GIVE UP ENERGY IN A DIRECTION ASSISTING SAID FLUID DISPLACING PORTION IN PRESSURIZING FLUID AT SAID REAR BRAKE CYLINDERS AFTER ACTUATION OF SAID VALVE.