GB1029774A - Infrared burner and method of producing infrared radiation - Google Patents

Abstract

1,029,774. Radiation burners; reflectors. HUPP CORPORATION. July 26, 1963 [Dec. 11, 1962], No. 29666/63. Headings F4R and F4T. An infra-red burner comprises means for supplying a combustible gas or liquid and all of the air required for its combustion to a distribution chamber feeding a thin perforated plate on which the mixture burns. Gas is supplied by a pipe 11 and a valve 12 to a spud 14 disposed in the inlet of a Venturi 18. Air is induced into the Venturi by the gas flow and the mixture is fed to a distribution chamber made of aluminized steel. The open bottom of the chamber is closed by a perforated flat or crowned radiating plate 34 of stainless steel, Inconel or Nichrome. The perforations may be circular, square, rectangular or crescent-shaped or of irregular shape. A Nichrome wire screen 42 or a second perforated plate or a plurality of spaced rods or strips is supported about “ inch from the outer surface of the plate 34. The mixture burns on the outside of the plate 34 and heats the plate to incandescence. The burner may be provided with a reflector. The Venturi may be replaced by a premixer. The burner shown in Fig. 9 has a cylindrical perforated radiating plate 108 supported on a Venturi 104 supplying an air/gas mixture to the interior of the radiating plate. The end of the cylinder remote from the Venturi is closed by a cap. A second cylindrical perforated plate or wire screen 119 surrounds the radiating plate 108. A polished aluminium paraboloid reflector 122 surrounds the burner. Two cylindrical burners may be arranged with their end caps juxtaposed to provide a long tubular source of radiation, Figs. 12, 13 (not shown). The source is surrounded by an aluminium reflector of parabolic cylindrical form, the axes of the cylindrical radiating plates coinciding with the locus of focal points of reflector sections. The reflector may be constructed in two identical halves which are hinged to a pivot-pin extending parallel to the source and secured at its ends to a channel-shaped plate fixed to the two Venturis. Screws extend through arcuate slots in the end walls of the reflectors into engagement with the ends of the channel-shaped plate. A plurality of these elongated burners may be mounted in parallel side-by-side relation, Fig. 14 (not shown), or the two outer burners may be tilted inwardly so that the radiation is concentrated on an object, Fig. 15 (not shown), or the outer burners may be tilted outwardly. In another embodiment, Fig. 16 (not shown), the radiating element is cone-shaped; its smaller end is supplied with a gas/air mixture and its large end is closed either by a perforated spherical radiating plate or by an imperforate cap. A conical wire mesh screen surrounds the conical radiating element and a flat or spherical wire mesh screen is mounted outside the perforated radiating plate closing the large end of the element. The burner is surrounded by a parabolic reflector having its apex at the smaller end of the radiating element. In another burner, Fig. 17 (not shown), a conical radiating element is supplied with a mixture of atomized oil and air. Either an atomizer nozzle discharges into the open end of a Venturi connected to the radiating element, or an electrically-driven blower and a nozzle suppply air and oil to a tapered tube leading to the radiating element, Fig. 18 (not shown). The diameter and taper of the radiating element are such that the element forms a prolongation of the Venturi. Two apertured plates mounted at the junction of the element and the Venturi vaporize the oil spray. The burner is surrounded by a parabolic reflector having its focal point at the centroid of the conical radiating element. In another burner, Figs. 19, 20 (not shown), a spud supplies fuel to the open end of a Venturi leading to a box-shaped distribution chamber closed by a semi-cylindrical, outwardly concave perforated radiating element. A pipe to be heated is located on the axis of the radiating element. The radiating element may have a parabolic section or it may be a surface of revolution such as a cone or a hemisphere. Another burner, Fig. 22 (not shown), has a cylindrical radiating element enclosed in a boxlike distribution chamber fed at two opposite ends with a fuel/air mixture by two Venturis. The cross-section of the cylindrical radiating element may be circular or elliptical or formed by two parabolas in mirror image arrangement. Another burner, Fig. 21 (not shown) has a cylindrical or frusto-conical radiating element closed at both ends by plates and a Venturi passes through one end plate to supply a mixture of gas and air to the inside of the radiating element. A reflector surrounding the radiating element has a shape generated by revolving a semi-parabola about the axis of the radiating element with the principal axis of the parabola coinciding with the surface of the radiating element. The reflector is secured to the Venturi by bolts adapted to engage in a series of holes in the Venturi so that the position of the element in the reflector can be varied. A vertical stack is secured to the upper end of the reflector.