Patent ID: 6779380
Filing Date: 2004-08-24
Classification: A47L,G01N

Abstract:
A safety vacuum cleaner including a measuring system for residual dust monitoring, comprising:a housing including an air passage having an inlet, an outlet, and a flow cross section; a turbine at least partially disposed within said air passage, said turbine rotatable to move an air stream through said air passage, the air stream containing dust particles, said turbine electrically grounded such that electrical charges associated with the particles are removed upon contact of the particles with said turbine; a filter element disposed within said air passage; and at least one electrode disposed within said air passage downstream of said turbine, said electrode shaped as a grid covering said flow cross section of said air passage, said electrode conducting an electrical current responsive to contact with uncharged particles and emitting a measurement signal indicative of the amount of the particles in the air stream.