# US 8,585,397 B2 · Hot air generator > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,585,397 B2 - Document ID: US8585397B2 - Status: Granted - Kind: B2 - Application number: 12/567,052 - Filed: 2009-09-25 - Published: 2010-04-01 - Granted: 2013-11-19 - Earliest claimed: 2008-09-26 - Assignees: Guilbert Express - Applicants: Yves Guillou; Christophe Le Drappier - Inventors: Yves Guillou; Christophe Le Drappier - Web page: https://patentgrep.com/patent/US8585397B2 ## CPC - F24H 9/0052: {for air heaters} - F23D 14/38: Torches, e.g. for brazing or heating (nozzles F23D14/48) - Y10T 137/0352: Controlled by pressure - Y10T 137/7826: With valve closing bias - F24H: FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL (steam generation F22) - F23D: BURNERS - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A hot air generator comprising a handle (12), an elongated nozzle (14), flame generating means (6), a venturi (4), a gas conduit (162) intended to bring a combustible gas into the elongated nozzle (14) and at the flame generating means (6), an air conduit (164) intended for bringing compressed air into the elongated nozzle (14) and downstream from the venturi; characterized in that the generator further comprises a servocontrolled pressure regulator (2) controlling a gas pressure (Pd.g) in the gas conduit (162) depending on an air pressure (Pd.a) in the air conduit (164). ## Claims ### Claim 1 A portable hot air generator comprising: a handle comprising an igniter; an elongated nozzle bound to the handle comprising an outlet end for ejecting hot air; a flame generator inside the elongated nozzle; a venturi upstream from the flame generator, formed on the elongated nozzle; a gas conduit passing through the handle to bring a combustible gas into the elongated nozzle and at the flame generator, the gas conduit extending through the handle and up to the flame generator; an air conduit passing through the handle to bring compressed air into the elongated nozzle and upstream from the venturi; a servocontrolled pressure regulator controlling a gas pressure in the gas conduit depending on air pressure in the air conduit; and wherein the flame generator comprises a tube, a burner and a gas injector each placed within the nozzle, the tube being positioned at least partly around the burner for cutting a flow of fresh air into two. ### Claim 2 (depends on 1) The generator according to claim 1, wherein the tube is a necked tube, a section of the necked tube being narrowed at its portion closest to the outlet end of the nozzle. ### Claim 3 (depends on 1) The generator according to claim 1, wherein the gas injector comprises a bore, having the same axis as the nozzle, for inserting the burner and at least one orifice through which the gas flows out, this/these orifice s) being positioned so that the gas flows out tangentially to the burner. ### Claim 4 (depends on 1) The generator according to claim 1, wherein the burner is a burner with a stabilized flame, wherein the generated flame remains fixed in the same location. ### Claim 5 (depends on 4) The generator according to claim 4, wherein the burner with a stabilized flame is either a burner stabilized by a wake effect or a Coanda burner. ### Claim 6 (depends on 1) The generator according to claim 1, wherein the igniter is a piezo-electric igniter coupled to an electrically conducting wire in contact with it and which extends up to the flame generator. ### Claim 7 (depends on 1) The generator according to claim 1, wherein the servocontrolled pressure regulator comprises a control chamber in fluid communication with the air conduit and downstream from an air expansion chamber, a high pressure gas chamber, and a gas expansion chamber in fluid communication with the gas conduit, wherein the control chamber is separated from the gas expansion chamber by a varying member moving or deforming in response to a pressure difference between a pressure prevailing in the control chamber and a pressure prevailing in the gas expansion chamber, a first stress member opposing the displacement or deformation of the varying member when the latter moves or deforms towards the gas expansion chamber. ### Claim 8 (depends on 7) The generator according to claim 7, wherein the varying member is a disc moving translationally in response to the pressure difference between the pressure prevailing in the control chamber and the pressure prevailing in the gas expansion chamber, the disc having on its edges an O-ring gasket with which sealing between the control chamber and the gas expansion chamber may be ensured. ### Claim 9 (depends on 7) The generator according to claim 7, wherein the varying member is a membrane which deforms in response to the pressure difference between the pressure (Pd.a) prevailing in the control chamber and the pressure (Pd.g) prevailing in the gas expansion chamber, the membrane having sealably fixed edges on a wall of the control chamber and the gas expansion chamber. ### Claim 10 (depends on 7) The generator according to claim 7, wherein the servocontrolled pressure regulator further comprises a second stress member suitable for generating a pressure offset between the pressure prevailing in the control chamber and the pressure prevailing in the gas expansion chamber. ### Claim 11 (depends on 10) The generator according to claim 10, wherein the second stress member is a second spring provided in the control chamber and intended to generate an offset so that the gas pressure in the gas conduit is always larger by a substantially constant amount than the air pressure in the air conduit. ### Claim 12 (depends on 11) The generator according to claim 11, wherein the second spring has a supporting point with fixed height in the control chamber and is intended for generating a substantially constant offset. ### Claim 13 (depends on 11) The generator according to claim 11, wherein the second spring has a supporting point of variable height in the control chamber and is intended for generating a variable offset. ### Claim 14 (depends on 10) The generator according to claim 10, wherein the second stress member is a second spring provided in the gas expansion chamber and intended for generating an offset so that the gas pressure in the gas conduit is always less by a substantially constant amount than the air pressure in the air conduit. ### Claim 15 (depends on 1) The generator according to claim 1, wherein the gas injector further comprises an inner toric space in fluid communication with the gas conduit, the inner diameter of which is larger than the diameter of the bore, one or more through-orifices putting the toric space in fluid communication with the inside of the nozzle, on a surface facing the outlet end of the nozzle, the bore, the toric space and the nozzle substantially having the same axis.