when was the first dyson vacuum cleaner invented
Dyson (company) Dyson developed 5,127 prototype designs between 1979 and 1984. The first prototype vacuum cleaner, a red and blue machine, brought Dyson little success, as he struggled to find a licensee for his machine in the UK and America. Manufacturing companies like Hoover did not want to license the design, probably because the vacuum bag market was worth $500m so Dyson was a threat to their profits.[5]
Incandescent light bulb Early lamps, and some small modern lamps used only a vacuum to protect the filament from oxygen. This however increases evaporation of the filament, albeit it eliminates the heat losses.
DeWalt After buying the company in 1949, American Machine & Foundry Co., Inc. sold it to Black & Decker in 1960.
Fidget spinner As of 2017, the patent status of the various fidget spinners on the market was unclear.[8]
Noise pollution Up until the 1970s governments tended to view noise as a "nuisance" rather than an environmental problem.
Vikramashila Vikramashila was founded by