Method of and apparatus for conveying powdered or granular material

Abstract

A rotor (1) of a machine for spraying concrete, mortar or a refractory lining material comprises conveying chambers (11') arranged concentrically around its axis, and delimited by cylindrical walls (11) of a porous, air-permeable material, the inside of the walls (11) being machined smooth. Each cylindrical wall (11) is surrounded by an air chamber (10), each of which is acted upon, between a charging point (26) and a discharge point (27), by the pressure of a compressed air source (32) so as to produce air flows which pass through the porous walls (11) into the conveying chambers (11'). The material to be conveyed by the conveying chambers (11') between the charging point (26) and the discharge point (27) is at least in the regions close to the wall acted upon by these air flows so as to prevent the material from adhering to the chamber walls (11'). The discharge through the discharge opening (27) into a conveying line (30) takes place essentially by gravity and by the action of an injector nozzle (31). Since the air flows supplied through the chamber walls (11) are only small, the action of the injector nozzle (21) is not disturbed by compressed air surges, so that a uniform conveying of the material through the conveying line (30) is possible.

Dependencies are inferred from the claim text.