Means for igniting a gaseous fuel burner

Claim 1

IN APPARATUS OF THE CLASS DESCRIBED HAVING A GASEOUS FUEL BURNER AND MEANS FORMING A PATH OF FLOW OF GASEOUS FUEL THERETO, VALVE MEANS IN THE PATH OF FLOW, THE VALVE MEANS BEING BIASED TO FLOW-PREVENTING POSITION AND MOVABLE TO FLOW-PERMITTING POSITION WITH RESPECT TO GASEOUS FUEL FLOW, THE COMBINATION OF AN ELONGATED FLASH-BACK TUBE HAVING A FIRST OPENING AT ONE END THEREOF AND A SECOND OPENING AT THE OPPOSITE END THEREOF AT WHICH THE BURNER IS ADAPTED TO BE IGNITED, MOUNTING MEANS FOR MOUNTING THE FLASH-BACK TUBE FOR MOVEMENT BODILY IN THE DIRECTION OF ITS LENGTH ALONG A FIXED HORIZONTALLY EXTENDING LINE, THE TUBE BEING BODILY MOVABLE ON THE MOUNTING MEANS ALONG THE LINE BETWEEN AN INOPERATIVE POSITION AND AN OPERATIVE POSITION IN WHICH THE FIRST OPENING AT THE ONE END OF THE TUBE IS ADAPTED TO RECEIVE GASEOUS FUEL DISCHARGED FROM THE BURNER WHEN THE VALVE MEANS IS MOVED TO ITS FLOW-PERMITTING POSITION WHEREBY, WHEN THE GASEOUS FUEL RECEIVED BY THE TUBE AT THE FIRST OPENING AT THE ONE END THEREOF IS IGNITED AT THE SECOND OPENING AT THE OPPOSITE END THEREOF, THE FLAME PRODUCED WILL FLASH BACK THROUGH THE TUBE TO IGNITE THE GASEOUS FUEL AT THE BURNER, AND THE FLASH-BACK TUBE IN ITS INOPERATIVE POSITION BEING INEFFECTIVE TO RECEIVE AT THE FIRST OPENING AT THE ONE END THEREOF GASEOUS FUEL DISCHARGED FROM THE BURNER WHEN THE VALVE MEANS IS MOVED TO ITS FLOW-PERMITTING POSITION.