Abstract: An insulated firing chamber has oppositely disposed sidewalls with a plurality of aligned pairs of holes. A plurality of infrared lamps are disposed in the chamber. The end terminals of the lamps pass through the respective pairs of holes to the exterior of the chamber. The end terminals of the lamps are enclosed by sealed compartments so the only way for gas to escape from the compartments is through the holes in the sidewalls of the firing chamber. Nonreactive gas under pressure is introduced into the compartments to induce unidirectional gas flow through the holes into the firing chambers. The gas introduced into the compartments cools the end terminals of the lamps without danger of contaminating the environment inside the firing chamber. The compartments each have an access opening, a removable hatch that engages a gasket on the compartment around the opening to seal the opening when the hatch is in place.

Abstract: An infrared furnace has a firing chamber in which a source of infrared energy is disposed and an elongated envelope transparent to the infrared energy extending through the firing chamber. The envelope has first and second open ends outside the firing chamber. First and second baffle chambers surround the respective first and second ends of the envelope. A product conveyor travels through the furnace via the baffle chambers and the envelope. Gas flow is prevented from the exterior of the furnace into the baffle chambers and from the firing chamber into the baffle chambers. Non-atmospheric gas is supplied to the baffle chambers so as to create therein a superatmospheric pressure which prevents gas flow into the baffle chambers from the exterior of the furnace. The non-atmospheric gas is exhausted from one of the baffle chambers, thereby inducing flow of the non-atmospheric gas from the other baffle chamber through the envelope.

Abstract: Mounting devices are provided for mounting the end portions of a replaceable infrared lamp on the sidewalls of heating chamber formed of a compressed insulation material with sheet metal covers on the outer surface thereof. Each mounting device comprises a ceramic holder having a hollow cylindrical body with a shoulder on the outer end thereof and a bottom wall on the inner end thereof. The bottom wall has a concentric circular opening with diametrically disposed notches. One of the ceramic holders is positioned in each of a pair of opposing holes in the sidewalls with its shoulder secured to the sheet metal cover by a sealant. The lamp is held with its end portions extending through the circular openings in the bottom walls of the ceramic holders so that the metal terminals of the lamp protrude outside the sidewalls.