Safety t fitting with check valve

Claim 1

A SAFETY T FITTING SAID T FITTING ADAPTABLE TO BE AFFIXED TO A GAS MAIN AT AN OPENING IN THE MAIN, SAID T FITTING COMPRISING: A TUBULAR BODY MEMBER ADAPTABLE TO BE AFFIXED SUBSTANTIALLY UPRIGHT AT THE LOWER END THEREOF TO SAID MAIN AT SAID OPENING IN SAID MAIN, SAID TUBULAR BODY MEMBER HAVING AN OUTLET OPENING THEREIN INTERMEDIATE THE LENGTH THEREOF, AND AN INTERNAL ANNULAR SEATING SHOULDER THEREIN BELOW SAID OUTLET OPENING AND ADJACENT SAID LOWER END, SAID TUBULAR BODY MEMBER HAVING THREADS FORMED INTERNALLY THEREOF FROM THE UPPER END TO SUBSTANTIALLY SAID SEATING SHOULDER; A TUBULAR, EXTERNALLY THREADED FLOW RATE CHECK MEMBER THREADABLY POSITIONED WITHIN SAID TUBULAR BODY MEMBER BETWEEN SAID OPENING THEREIN AND SAID LOWER END THEREOF, SAID CHECK MEMBER HAVING AN INTERNAL SEATING SURFACE IN THE LOWER PORTION THEREOF AND AN EXTERNAL ANNULAR SEATING SURFACE ON THE LOWER END THEREOF WHEREBY SAID CHECK MEMBER IS THREADABLY ADVANCEABLE TO SEALABLE ENGAGEMENT WITH SAID BODY INTERNAL ANNULAR SEALING SHOULDER; A BALL RETAINING MEANS AFFIXED TO THE LOWER PORTIONN OF SAID CHECK MEMBER INCLUDING A TUBULAR PORTION, SAID BALL RETAINING MEANS BEING ADAPTED TO LOOSELY SUPPORT A BALL SUBSTANTIALLY AXIALLY OF SAID CHECK MEMBER AND BELOW SAID INTERNAL SEATING SURFACE; A VALVE BALL LOOSELY SUPPORTED WITHIN SAID BALL RETAINING MEANS, SAID BALL OF A DIAMETER LARGER THAN THE OPENING OF SAID TUBULAR CHECK MEMBER AND FORMING WITH SAID TUBULAR PORTION A RESTRICTED PASSAGE WHEREBY GAS FLOW EXCEEDING A PREDETERMINED RATE WILL RAISE SAID BALL TO SEALABLY ENGAGE SAID SEATING SURFACE THEREOF TO CLOSE SAID OPENING THERETHROUGH; AND MEANS CLOSING THE UPPER END OF SAID TUBULAR BODY MEMBER.