Fluid pressure braking system

Claim 1

SAFETY BRAKE MECHANISM FOR A TRACTOR-TRAILER BRAKING SYSTEM INCLUDING FIRST AND SECOND SOURCES OF FLUID PRESSURE CARRIED ON THE TRACTOR, SAID SOURCES BEING ISOLATED FROM EACH OTHER, A TRAILER EMERGENCY CONDUIT CONNECTED TO SAID FIRST SOURCE AND A FLUID PRESSURE RESPONSIVE TRACTOR PROTECTION VALVE INCLUDING A CONTROL PORT, SAID VALVE BEING DISPOSED IN SAID EMERGENCY CONDUIT TO DISRUPT OR ESTABLISH COMMUNICATION BETWEEN SAID SOURCE AND SAID CONDUIT OR BETWEEN SAID CONDUIT AND ATMOSPHERE DEPENDING ON WHETHER THE PRESSURE AT SAID CONTROL PORT IS ABOVE OR BELOW PREDETERMINED LEVELS, IN COMBINATION THEREWITH, A BRAKE ACTUATOR ON THE TRACTOR, A SPRING APPLIED BRAKE LOCKING MEANS FOR LOCKING THE ACTUATOR IN BRAKE APPLIED POSITION, FLUID PRESSURE ACTUATED RELEASE MEANS FOR RELEASING SAID BRAKE LOCKING MEANS, A MANUALLY OPERABLE CONTROL VALVE HAVING AN INLET PORT CONNECTED TO SAID SECOND SOURCE OF FLUID PRESSURE, AN OUTLET PORT CONNECTED TO THE BRAKE LOCK RELEASE MEANS, AND AN ATOMSPHERIC PORT, SAID VALVE BEING MOVABLE BETWEEN A FIRST POSITION COMMUNICATING SAID INLET AND OUTLET PORTS WHILE DISRUPTING COMMUNICATION BETWEEN THE LATTER AND SAID EXHAUST PORT AND A SECOND POSITION DISRUPTING COMMUNICATION BETWEEN SAID INLET AND OUTLET PORTS WHILE COMMUNICATING THE LATTER WITH SAID EXHAUST PORT, A CONTROL CONDUIT COMMUNICATING THE CONTROL PORT OF SAID TRACTOR PROTECTION VALVE WITH SAID FIRST SOURCE OF FLUID PRESSURE, A SECOND FLUID PRESSURE RESPONSIVE VALVE MEANS INCLUDING VENT PASSAGE MEANS AND AN INLET PORT CONNECTED TO THE OUTLET PORT OF SAID MANUAL CONTROL VALVE, SAID SECOND VALVE BEING DISPOSED IN SAID CONTROL CONDUIT AND DISRUPTING OR ESTABLISHING COMMUNICATION BETWEEN SAID FIRST SOURCE AND SAID CONTROL PORT PORT OR BETWEEN SAID CONTROL PORT AND SAID VENT PASSAGE MEANS DEPENDING UPON WHETHER PRESSURE IS ADMITTED TO OR EXHAUSTED FROM THE BRAKE LOCK RELEASE MEANS AND CONSEQUENTLY TO OR FROM SAID INLET PORT OF SAID SECOND VALVE BY OPERATION OF SAID MANUAL CONTROL VALVE.