Gas-fueled catalytic infra-red heat producing element

1,057,729. Gas burners. UNIVERSAL OIL PRODUCTS CO. Nov. 25, 1963 [Nov. 30, 1962], No. 46383/63. Heading F4T. A catalytic infra-red heating element comprises an outer cylindrical metal gauze 1 spaced concentrically around a tubular core 7 comprising a plurality of layers 10, 11 of metal gauze of which at least the outer layer is coated with a noble metal comprising platinum or palladium or a platinum group metal or a combination of two or more of the members of the platinum group. Small percentages of thorium, ruthenium, tungsten and cesium may be added to the platinum group metal. In the embodiment shown the core 7 has five layers of which the outer three are coated with a noble metal. The outer metal gauze 1 may be coated with a noble metal. The mesh of the outer gauze is preferably larger than the mesh of the coated layers of the core 7 and the mesh of the inner un-coated layers of the core 7 is larger than the mesh of the outer coated layers of the core 7. The outer metal gauze 1 is supported by a cap member 3 and by an end-plate 4 having a central threaded opening 5 into which is screwed an aspirator unit supplying a mixture of propane and air. An igniting hole 2 is provided in the outer gauze 1 adjacent the air/butane inlet opening 5. The core 7 is formed by successively wrapping the layers into a tubular form and spot welding at spaced points; it is slidably fitted over a support member 8 on the end cap 3 and over a shoulder 6 on the end plate 4. Bolts, screws or clamps may be used between the core and the end cap and end plate. A single heating element is placed in a dished or parabolic reflector, Fig. 3 (not shown). A plurality of elements are arranged in a row in an elongated reflector, Fig. 4 (not shown). Each element is supplied with a fuel/air mixture from a header or each element has its own valve and air aspirator disposed between the element and a header supplied with fuel gas. The elements are close enough for one to light another. An element may have a fuel/air inlet at each end.