Locking device on hydraulic brakes to prevent theft of automobiles

Claim 1

A VALVE DEVICE FOR LOCKING FLUID UNDER PRESSURE IN AN HYDRAULIC LINE, SAID DEVICE COMPRISING A HOUSING HAVING TWO CHAMBERS THEREIN EACH OF WHICH HAS CONNECTION MEANS ADAPTED TO CONNECT SAID CHAMBERS INTO THE FLUID LINE, SAID HOUSING HAVING PASSAGE MEANS CONNECTING SAID CHAMBERS, A MOVABLE VALVE ELEMENT FOR CLOSING SAID PASSAGE MEANS AND LOCATED IN ONE CHAMBER WHICH IS ADAPTED TO COMMUNICATE WITH THAT PART OF THE FLUID LINE IN WHICH THE FLUID IS TO BE LOCKED UNDER PRESSURE, A FIRST SPRING MEANS ACTING ON SAID VALVE ELEMENT TO BIAS SAID VALVE ELEMENT INTO THE CLOSED POSITION, A SECOND SPRING MEANS ACTING ON SAID VALVE ELEMENT TO BIAS THE VALVE ELEMENT TO THE OPEN POSITION AGAINST THE ACTION OF THE FIRST SPRING MEANS, A DISPLACEABLE MEMBER CAPABLE OF MOVEMENT FROM ONE ALTERNATIVE POSITION TO ANOTHER ALTERNATIVE POSITION WITHIN THE CHAMBER ADAPTED TO COMMUNICATE WITH THAT PART OF THE PIPELINE EXTENDING FROM A SOURCE PRODUCING FLUID UNDER PRESSURE, SAID MEMBER ACTING ON SAID SECOND SPRING MEANS AND IN ONE OF THE ALTERNATIVE POSITIONS PLACING THE SECOND SPRING MEANS IN COMMISSION TO OVERCOME THE ACTION OF FIRST SPRING MEANS AND TO BIAS THE VALVE ELEMENT TOWARDS THE OPEN POSITION WHEN SAID VALVE ELEMENT IS HELD CLOSED BY THE FLUID LOCKED UNDER PRESSURE AND ALSO TO TRANSFER AND HOLD SAID VALVE ELEMENT IN THE OPEN POSITION AFTER EQUALIZING OF FLUID PRESSURE IN BOTH CHAMBERS TO PERMIT PASSAGE OF FLUID IN OPPOSITE DIRECTIONS, AND IN THE OTHER ALTERNATIVE POSITION OF SAID MEMBER THE SAID SECOND SPRING MEANS IS INEFFECTIVE AND THE FIRST SPRING MEANS ACTS ON THE VALVE ELEMENT TO HOLD SUCH ELEMENT IN THE CLOSED POSITION PERMITTING THE PASSAGE OF FLUID IN ONE DIRECTION, A LOCK OPERABLE BY A REMOVABLE KEY AND HAVING A MOVABLE PART COUPLED TO THE DISPLACEABLE MEMBER TO TRANSFER SAID DISPLACEABLE MEMBER TO THE ALTERNATIVE POSITIONS, AND SEALING MEANS BETWEEN SAID LOCK AND SAID CHAMBER HAVING SAID MEMBER THEREIN TO PREVENT ESCAPE OF FLUID UNDER PRESSURE PAST THE LOCK.