Muffler with internal passages formed in mesh-like fiber-filled cage

Claim 1

AN EXHAUST MUFFLER OF THE TYPE HAVING A SHELL FORMING AN IMPERFORATE OUTER TUBULAR CASING, IMPERFORATE END PLATES CLOSING THE ENDS OF THE TUBULAR CASING, AND INLET AND OUTLET PIPES, THE IMPROVEMENT WHICH COMPRISES: (1) A CAGE OF PERFORATE MATERIAL INSIDE THE SHELL AND EXTENDING FROM ONE END PLATE TO THE OTHER FOR THE FULL LENGTH OF THE MUFFLER AND FILLED WITH GAS-PERMEABLE SOUND-ABSORBING MATERIAL; (2) THE CAGE HAVING A MAJOR PORTION OF ITS PERIPHERY SPACED A SHORT DISTANCE FROM THE SHELL OF THE OUTER CASING TO FORM A NARROW PERIPHERAL GAS PASSAGE IN DIRECT CONTACT WITH SAID SHELL; (3) THE OUTER WALL OF THE CAGE BEING DEFORMED INWARDLY FOR SUBSTANTIALLY THE ENTIRE LENGTH OF THE CAGE TO FORM AN OPEN-SIDED INLET GAS PASSAGE THAT IS IN DIRECT COMMUNICATION WITH THE PERIPHERAL GAS PASSAGE; (4) THE OUTER WALL OF THE CAGE ON ITS SIDE OPPOSTE THE OPEN-SIDED INLET GAS PASSAGE BEING DEFORMED INWARDLY FOR SUBSTANTIALLY THE FULL LENGTH OF THE CAGE TO FORM AN OPEN-SIDED OUTLET GAS PASSAGE THAT IS IN DIRECT COMMUNICATION WITH THE PERIPHERAL GAS PASSAGE; (5) THE INLET PIPE COMMUNICATING WITH SAID OPEN-SIDED INLET GAS PASSAGE, AND THE OUTLET PIPE COMMUNICATING WITH SAID OPEN-SIDED OUTLET GAS PASSAGE; (6) WHEREBY THE STREAM OF INCOMING GAS IS DIVIDED, ONE PORTION PASSING FROM THE INLET GAS PASSAGE TO THE OUTLET GAS PASSAGE BY WAY OF THE PERIPHERAL GAS PASSAGE, AND ANOTHER PORTION PASSING FROM THE INLET GAS PASSAGE THROUGH THE SOUND-ABSORBING MATERIAL IN THE CAGE TO THE OUTLET GAS PASSAGE.