(under subclass 300) Cleaning apparatus having provisions for pulsating the air flow, the effect generally being to agitate the work such as the nap of a pile rug or the like.
(1) Note. This subclass includes patents for nozzles having a plurality of air passages with means to apply the air draft successively to the passages, the effect as to any one passage being a pulsating or intermittent air flow even though there is a more or less constant air flow through the nozzle as a whole.