Flashback-proof gas mixer

Claim 1

AN ANTI-FLASHBACK GAS MIIXER FOR A BURNER SYSTEM IN WHICH A FUEL GAS AND A COMBUSTIONSUPPORTING GAS ARE MIXED AND THE MIXTURE PASSES TO A PLACE OF COMBUSTION AT WHICH THE MIXTURE IS BURNED, COMPRISING A BODY PORTION HAVING SEPARATE INLET PASSAGES FOR THE FUEL GAS AND THE CONBUSTION-SUPPORTING GAS AND ALSO HAVING AN OUTLET FOR CONNECTION TO THE PLACE OF COMBUSTION, MEANS FORMING WITHIN THE BODY PORTION A MIXING CHAMBER FOR THE GASES ASSOCIATED WITH SAID OUTLET PASSAGE, SAID CHAMBER BEING SEPARATED FROM SAID INLET PASSAGES BY WALLS OF RELATIVELY GREAT MASS, AT LEAST ONE PASSAGEWAY THROUGH ONE OF SAID WALLS COMMUNICATING AT OPPOSITE SIDES WITH THE INLET PASSAGE FOR FUEL GAS AND THE MIXING CHAMBER, RESPECTIVELY, AND AT LEAST ONE PASSAGEWAY THROUGH ANOTHER OF SAID WALLS COMMUNICATING AT OPPOSITE SIDES WITH THE INLET PASSAGE FOR THE COMBUSTION-SUPPORTING GAS AND THE MIXING CHAMBER, RESPECTIVELY, SAID PASSAGEWAY HAVING A WIDTH IN A DIRECTION NORMAL TO THE DIRECTION OF THE FLOW OF THE GASES THERETHROUGH OF FROM ABOUT .004 INCH TO .030 INCH, THE WALLS DEFINING SAID PASSAGEWAYS HAVING A THICKNESS OF SAID DIRECTION GREATER THAN SAID WHICH OF THE PASSAGEWAYS AND ALSO HAVING SUFFICIENT HEAT-ABSORBING CAPACITY TO COOL BURNED MIIXED GASES PASSING THERETHROUGH ON A BACKFIRE SUFFICIENT TO PREVENT FLASHBACK.