Self-inflating balloon type formation tester

Claim 1

A FORMATION TESTER ASSEMBLY FOR SAMPLING FLUIDS FROM STRATA ENCOUNTERED IN A WELL BORE WHICH COMPRISES AN ELONGATED SUPPORT MEMBER ATTACHABLE TO THE LOWER END OF A DRILL PIPE AND HAVING A CENTRAL BORE COMMUNICATPACKER ATTACHED TO SAID SUPPORT MEMBER, SAID PACKER HAVING AT LEAST ONE TEST PORT IN A SIDE WALL THEREOF, A MECHANICALLY EXPANSIBLE PACKER SUPPORTED BY THE SUPPORT MEMBER ABOVE THE SAID INFLATABLE ELASTIC PACKER, MEANS FOR EXPANDING SAID MECHANICALLY EXPANSIBLE PACKER, A PASSAGEWAY WITHIN SAID ASSEMBLY TERMINATING AT ITS LOWER END WITHIN SAID INFLATABLE PACKER AND AT ITS UPPER END IN A PORT OPENING EXTERIORLY OF SAID ASSEMBLY ABOVE SAID MECHANICAL PACKER, SAID PASSAGEWAY LACKING COMMUNICATION WITH THE CENTRAL BORE OF THE SUPPORT MEMBER, A CONDUIT CONNECTING THE TEST PORT OF THE INFLATABLE ELASTIC PACKER WITH THE CENTRAL BORE OF THE SUPPORT MEMBER, A CHECK VALVE WITHIN SAID LAST NAMED CONDUIT AND A FRANGIBLE SEAL WITHIN AN UPPER SECTION OF SAID CENTRAL BORE ABOVE SAID LAST NAMED CONDUIT.