Locking device for an automotive hydraulic brake

Claim 1

IN COMBINATION WITH A HYDRAULIC BRAKE SYSTEM FOR AUTOMOTIVE VEHICLES, A MEANS FOR RETAINING THE FLUID IN SAID BRAKE SYSTEM, THE LATTER COMPRISING A BRAKE MASTER CYLINDER AND BRAKE WHEEL CYLINDERS, A FLUID LINE BETWEEN SAID BRAKE MASTER CYLINDER AND SAID BRAKE WHEEL CYLINDERS, MEANS FOR RETAINING FLUID UNDER PRESSURE IN SAID FLUID LINE, INCLUDING A CHACK VALVE MEMBER, SAID CHECK VALVE MEMBER COMPRISING A CYLINDER THE LONGITUDINAL AXIS OF WHICH IS VERTICALLY ORIENTED, SAID CYLINDER HAVING AN UPPER AND LOWER PORTION, SAID LOWER PORTION HAVING AN OPEN BOTTOM END, A PISTON DISPOSED IN SAID LOWER PORTION AND AXIALLY AND VERTICALLY MOVABLE FREELY THEREIN AND THROUGH SAID OPEN BOTTOM END OF SAID LOWER PORTION OF SAID CYLINDER SO THAT SAID PISTON CAN BE REMOVED FROM SAID OPEN BOTTOM END, SAID UPPER PORTION OF SAID CYLINDER DEFINING A CHAMBER AND THE LATTER FORMING A VALVE SEAT AT ITS BOTTOM, SAID CYLINDER DEFINING FURTHER A VERTICAL RECESS PROVIDING COMMUNICATION BETWEEN SAID LOWER PORTION OF SAID CYLINDER AND SAID CHAMBER, A SPRING BIASED BALL SITTING ON AND URGED ONTO SAID VALVE SEAT, SAID FLUID LINE FEEDING FROM SAID BRAKE MASTER CYLINDER TO SAID VERTICAL RECESS, A PUSHING PISTON ROD SECURED TO THE TOP OF AND AXIALLY MOVABLE WITH SAID PISTON, AND EXTENDING AXIALLY THROUGH SAID VERTICAL RECESS FOR ENGAGEMENT WITH THE BOTTOM SURFACE OF SAID BALL, CAM MEANS ENGAGING THE BOTTOM FACE OF SAID PISTON PROVIDING A SOLE MEANS FOR SUPPORTING AND RETAINING SAID PISTON IN POSITION WITHIN SAID LOWER PORTION OF SAID CYLINDER AND PROVIDING A LOWER ABUTMENT FOR SUPPORTING SAID PISTON, SAID PISTON BEING MOVED DOWNWARDLY SOLELY BY GRAVITY AND FLUID PRESSURE AGAINST SAID CAM MEANS, SAID CAM MEANS OPERABLE FOR LIFTING SAID PISTON AND, THEREBY, BY MEANS OF SAID PUSHING PISTON ROD LIFTING SAID BALL FROM ITS VALVE SEAT IN THE OPEN POSITION OF SAID CHECK VALUE MEMBER, AND SAID PUSHING PISTON ROD THUS LIFTING SAID BALL FROM ITS SEAT BY MOVING AXIALLY.