For many years, vacuum cleaners remained a luxury item, but after World War II they became a common piece of furniture among the middle class. Cyclonic-type vacuum cleaners (using centrifugal force to separate dust and solids) became popular in the 1990s, although some companies (notably Filter Queen and Regina) have been manufacturing these vacuum cleaners since 1928. The first cyclone-free vacuum cleaner, the CMS 1000, was patented by Amway in 1959. [7] [8] In 2004, the British company launched Airider - a vacuum cleaner that can, like the Hoover Constellation, hang on an air cushion. In 2008, the oldest operating vacuum cleaner failed, after it had worked for 70 years. [9] In the USSR, many models of manufactured vacuum cleaners had an outlet (discharge) pipe of the same design as the suction one. This made it possible, if necessary, to use the vacuum cleaner as a compressor, the power of which was enough, for example, for painting (whitewashing) ceilings with chalk whitewash using the paint spraying method. Sometimes such a sprayer of simple design was attached to the vacuum cleaner. Data