Tunnel-type conveyor oven having two types of heat sources

摘要

A tunnel-type conveyor oven having two types of heat sources is provided. The oven includes a conveyor for carrying items through the oven along a conveyor path. The conveyor has first and second opposite sides. A plurality of radiant heaters are located transverse to and extend across the conveyor path. The radiant heaters are spaced apart in a direction of the conveyor path. Each radiant heater includes an inner tube having a wall with a plurality of openings defined therethrough, an open first end and a second end. A burner is directed into the open first end of the inner tube. An outer tube is located around the inner tube. The outer tube has an outer surface which is adapted to radiate heat, a first end and a second end. An exhaust outlet is located on the second end of the outer tube. The radiant heaters are arranged such that with every other heater, the burners are located on the first side of the conveyor, and with the remaining heaters, the burners are located on the second side of the conveyor for uniform radiant heat distribution across the conveyor. An exhaust manifold is connected to the exhaust outlet of at least one of the heaters. A penthouse chamber is located above the plurality of radiant heaters, and the exhaust manifold is connected to the penthouse chamber. A convection heating system is also provided which includes an upper convection heater located above and extending across the conveyor path. The upper convection heater has an upper plenum with supply areas located between each of the radiant heaters. The supply areas each have a plurality of openings directed toward the conveyor path. A lower convection heater is located below the conveyor path and includes a lower plenum having a plurality of openings directed toward the conveyor path. A convection air manifold is connected between the penthouse chamber and the upper and lower plenums to deliver the products of combustion from the radiant heaters collected in the penthouse chamber to the upper and lower plenums to provide convective heat along the conveyor path.