Tire pressure indicator

Claim 1

A TIRE PRESSURE INDICATOR FOR A TUBELESS TIRE MOUNTED ON A RIM IN WHICH THERE IS PROVIDED AN OPENING THROUGH SAID RIM TO THE INTERIOR OF SAID TIRE, SAID INDICATOR COMPRISING, IN COMBINATION: AN ENCLOSURE; AN INTERNAL DIAPHRAGM DIVIDING THE INTERIOR OF SAID ENCLOSURE INTO FIRST AND SECOND CHAMBERS; AN EXTENDING PORTION CONNECTED TO SAID ENCLOSURE AND COMMUNICATING WITH SAID FIRST CHAMBER, SAID PORTION BEING AT LEAST PARTLY TRANSPARENT AND ADAPTED TO PASS THROUGH SAID OPENING WHEN SAID ENCLOSURE IS POSITIONED WITHIN SAID TUBELESS TIRE SO THAT SAID PORTION IS VISIBLE FROM THE EXTERIOR OF SAID TIRE; AND AN INDICATING ROD HAVING ONE END SECURED TO SAID DIAPHRAGM FOR MOVEMENT THEREWITH AND ITS OTHER END PROJECTING INTO SAID EXTENDING PORTION SO AS TO BE VISIBLE THERETHROUGH WHEN SAID DIAPHRAGM IS IN A FIRST POSITION, SAID FIRST CHAMBER BEING HERMETICALLY SEALED UNDER A GIVEN PRESSURE CORRESPONDING TO NORMAL TIRE PRESSURE, SAID GIVEN PRESSURE ACTING AGAINST ONE SIDE OF SAID DIAPHRAGM, AND SAID SECOND CHAMBER BEING IN FLUID COMMUNICATION WITH THE INTERIOR OF SAID TIRE SO THAT ACTUAL TIRE PRESSURE ACTS ON THE OTHER SIDE OF SAID DIAPHRAGM WHEREBY A CHANGE IN SAID ACTUAL TIRE PRESSURE MOVES SAID DIAPHRAGM TO VARY THE POSITION OF SAID ROD WITHIN SAID EXTENDING PORTION.