Abstract: A device is provided for the air-based solar thermal generation of process heat in order to assist in drying processes. The device may add the solar-thermally generated hot air as a function of the relative temperature of the solar-thermally generated hot air as a partial flow of the process air generated by other systems.

Abstract: A device is provided for the air-based solar thermal generation of process heat in order to assist in drying processes. The device may add the solar-thermally generated hot air as a function of the relative temperature of the solar-thermally generated hot air as a partial flow of the process air generated by other systems.

Abstract: In known rack dryers, the drying effect is weaker in the outer area on the side of the air intake into the pipe chambers than in the other areas. Said weaker drying effect is caused by turbulence in this area, which leads to a drop in the static pressure. The aim of the invention is to provide a dryer which ensures even drying of the goods across the entire width, even in the problem areas. The rack dryer is equipped with conductive bodies (20, 26) which are located on the partition wall (5) and which streamline the current in the area of the air intake into the pipe chambers in such a way, that a predominantly even static pressure prevails throughout the entire pipe chamber. The invention can be used for drying sandwich-type plaster board or wood veneer.

Abstract: An apparatus for smoothing a workpiece has a housing that is displaced relative to the workpiece in a direction and that carries a pair of augers provided with respective screwthreads having outer edges in contact with the workpiece. These augers are rotated on the housing about respective generally parallel axes transverse to the direction so as to scrape the workpiece with the screwthreads. Furthermore the augers are of such a hand and the are rotated in such a direction that the augers exert on the workpiece opposite axially directed forces.