Abstract: A pug mill having a housing including a drive and bearings for rotatably mounting and driving a cantilevered shaft extending from one side of the housing. Associated with the housing and concentrically arranged about the shaft are, in seriatim, a vacuum chamber, a mixing chamber, an extruder and a reduction cone. A port about the shaft is positioned between the vacuum chamber and the mixing chamber. A source of vacuum maintains a vacuum within the vacuum chamber and creates a vacuum within the mixing chamber by air passing through the port. An auger associated with the shaft positioned within the extruder forces clay toward the reduction cone. This creates a seal for maintaining vacuum within the mixing chamber and extrudes cylindrical blocks of conditioned clay without significant air bubbles.

Abstract: A combination clay mixing and extruding apparatus for mixing dry powders and water to form a moist clay which can alternately be held in the mixing chamber, or, as desired, can be automatically extruded into cylindrically shaped logs. Due to the unique design of the apparatus, the extrusion operation is commenced by merely reversing the direction of rotation of the drive means of the device. For more compactness, the unit embodies in-line mixing and extrusion chambers. A unitary shaft drives both the mixing blades of the mixing chamber and the extruding auger of the extrusion chamber. The shaft is cantilevered within the chambers and is journaled in bearings located exteriorly of the chambers so as to protect them from the abrasive and corrosive effects of the powder and water.

Abstract: A simulation of the audio characteristics of a commercial broadcast channel is provided to permit the person mixing a master recording to hear the recording as it will be heard by the public.