Valve cap pressure indicator for tires

Claim 1

A VALVE CAP PRESSURE INDICATOR FOR A PNEUMATIC TIRE, COMPRISING A CYLINDRICAL CORE TIGHTLY ENGAGEABLE AT ONE END ON A VALVE STEM OF SAID TIRE, SAID CORE HAVING A PROJECTING AXIAL STUD AT SAID END FOR HOLDING THE VALVE IN AN OPEN CONDITION, A GENERALLY CYLINDRICAL COVER CONCENTRIC WITH SAID CORE AND AXIALLY MOVABLE WITH RESPECT TO THE CORE, A SPRING IN SAID COVER BIASING THE COVER AXIALLY OUTWARDLY OF THE CORE, SAID CORE AND COVER HAVING OVERLAPPING FLANGES DEFINING AN AIR CHAMBER THEREBETWEEN, AND A RESILIENT COLORED PLASTIC SLEEVE AROUND THE CORE CONTACTING THE FLANGE OF THE COVER AND SEALING THE CHAMBER THEREAT, SAID CORE HAVING A PASSAGE EXTENDING FROM SAID END TO SAID CHAMBER TO PASS AIR INTO THE CHAMBER FOR FORCING THE FLANGES APART WHEN THE AIR PRESSURE IN SAID CHAMBER EXCEEDS A PREDETERMINED PRESSURE DETERMINED BY TENSION IN SAID SPRING SO THAT THE COVER PARTIALLY ENCLOSES SAID SLEEVE, SAID COVER HAVING A RECESS THEREIN AND HOLES COMMUNICATING BETWEEN THE RECESS AND THE EXTERIOR OF THE COVER, SAID CORE HAVING A CYLINDRICAL EXTENSION EXTENDING INTO THE RECESS AND CLOSING THE HOLES WHEN PRESSURE IN SAID CHAMBER IS GREATER THAN A CERTAIN CRITICAL PRESSURE, SAID EXTENSION CLEARING THE HOLES WHEN PRESSURE IN SAID CHAMBER IS LESS THAN THE CRITICAL PRESSURE TO CAUSE A WHISTLING SOUND AS THE TIRE ROTATES WITH THE INDICATOR.