Fluid pressure brake apparatus with periodic acknowledgment type safety control

Claim 1

A FLUID PRESSURE SAFETY CONTROL SYSTEM COMPRISING CONTROL CONDUIT MEANS NORMALLY CHARGED WITH FLUID AT A PRESELECTED PRESSURE AND IN WHICH A REDUCTION IN EXCESS OF A CERTAIN AMOUNT FROM SAID PRESELECTED PRESSURE IS EFFECTIVE TO INITIATE A PENALTY CONTROL OPERATION, FLUID PRESSURE DIFFERENTIAL RESPONSIVE VALVE MEANS INCLUDING FLUID PRESSURE RESPONSIVE MEANS SUBJECTABLE TO OPPOSING FLUID PRESSURES AND OPERABLE FROM ONE POSITION, IN WHICH A VENTING COMMUNICATION FOR EFFECTING REDUCTION OF FLUID PRESSURE IN SAID CONTROL CONDUIT MEANS IS OPENED, TO ANOTHER POSITION, IN WHICH SAID VENTING COMMUNICATION IS CLOSED AND FURTHER REDUCTION OF FLUID PRESSURE IN SAID CONTROL CONDUIT MEANS IS TERMINATED, AND REVERSELY, DEPENDING UPON THE DIRECTION OF THE RESULTANT DIFFERENTIAL FORCE BETWEEN SAID OPPOSING FLUID PRESSURES, AND MEANS INCLUDING MANUALLY OPERABLE CONTROL MEANS OPERATIVE IN ONE POSITION FOR EFFECTING SIMULTANEOUS SUPPLY OF PRESSURIZED FLUID TO OPPOSITE SIDES OF SAID FLUID PRESSURE RESPONSIVE MEANS AT DIFFERENT RELATIVE RATES AND OPERABLE TO A DIFFERENT POSITION FOR EFFECTING SIMULTANEOUS RELEASE OF FLUID PRESSURE FROM SAID OPPOSITE SIDES OF SAID FLUID PRESSURE RESPONSIVE MEANS AT DIFFERENT RELATIVE RATES FOR SO CONTROLLING THE DIRECTION OF SAID RESULTANT DIFFERENTIAL FORCE AS TO EFFECT ALTERNATE OPERATION OF SAID FLUID PRESSURE DIFFERENTIAL RESPONSIVE VALVE MEANS FROM ITS SAID ONE POSITION TO ITS SAID OTHER POSITION AND REVERSELY SO AS TO PREVENT REDUCTION OF FLUID PRESSURE IN SAID CONTROL CONDUIT MEANS IN EXCESS OF SAID CERTAIN AMOUNT.