Abstract: In a kiln for firing ceramic workpieces, which kiln is composed of two opposed side walls and a top wall enclosing an elongate kiln chamber, and elements for introducing jets of heating or cooling gases into the kiln chamber at locations spaced along the length of the kiln, the elements are located for directing the jets produced thereby vertically in the region of the side walls of the kiln, and deflector stones are disposed at a distance from the elements for deflecting the jets and gases within the chamber transversely of the length of the kiln.

Abstract: A system for conveying ceramic workpieces through a roller hearth furnace, composed of: a plurality of conveying rollers rotatably mounted one behind the other in the workpiece conveying direction with their axes of rotation parallel to one another and perpendicular to the conveying direction, and defining a common support plane for the workpieces; a plurality of drive gears each associated, and mounted coaxially, with a respective roller and provided with an axial bore having a diameter larger than that of its respective roller, with one axial end of each roller extending into the bore of its associated drive gear and being disconnectably but securely connected to its associated drive gear; and a plurality of transmission gears each mounted for rotation about an axis parallel to the axes of rotation of the rollers and each engaging an associated pair of adjacent drive gears to form a gear train in which the drive gears alternate with the transmission gears and the application of power to the gear train cause