Safety cap assembly for pressurized founts of gasoline burning devices

Claim 1

IN A SAFETY CAP ASSEMBLY, INCLUDING A FILLER BUSHING HAVING A LOWER PORTION FOR ATTACHMENT TO A PRESSURIZED FOUNT OF A GASOLINE BURNING DEVICE AND AN EXTERNALLY THREADED UPPER PORTION, AN INTERNALLY THREADED CLOSURE CAP RECEIVED ON SAID BUSHING UPPER END PORTION IN THREADED ENGAGEMENT THEREWITH, AND GASKET MEANS MOUNTED WITHIN SAID CAP FOR ESTABLISHING SEALING ENGAGEMENT WITH THE UPPER END OF SAID BUSHING AT A LEVEL OUTWARDLY OF THE ZONE OF THREADED ENGAGEMENT BETWEEN SAID CAP AND BUSHING, THE MEANS FOR ACHIEVING A SAFE RELEASE OF THE FOUNT PRESSURE WHEN SAID CAP IS UNSCREWED CHARACTERIZED BY SAID CAP BEING PROVIDED WITH A PLURALITY OF CIRCUMFERENTIALLY SPACED, AXIALLY ALIGNED CHANNELS EXTENDING INWARDLY FROM THE LOWER END THEREOF TO THE LEVEL OF SAID SEALING ENGAGEMENT, SAID CAP BEING FORMED OF A SUBSTANTIALLY SOFTER METAL THAN SAID BUSHING, SAID CHANNELS HAVING A GREATER DEPTH THAN THE ROOT DEPTH OF THE THREADS IN SAID CAP, AND PROVIDING OPEN PATHS OF COMMUNICATION FOR BOTH LIQUID AND VAPOR BETWEEN THE EXTERIOR ATMOSPHERE AT THE BOTTOM OF SAID CAP AND SAID LEVEL OF SEALING ENGAGEMENT ADJACENT SAID GASKET.