Combination dust container for vacuum cleaner and signalling device

Claim 1

A combination of a vacuum cleaner, dust container and a signalling device for indicating the amount of dust and dirt filling in said dust container comprising: said dust container having a relatively rigid attachment plate and an air pervious part secured thereto, said attachment plate having an inlet opening for dust laden air, said signalling device having at least a partially transparent cylinder, a member in said cylinder, a first channel communicating one end of the cylinder with the interior of said dust container through the air pervious part of said attachment plate, a second channel communicating the other end of said cylinder with a location at the exterior of said dust container, said member being movable in said cylinder by the action of the pressure difference between the interior and exterior of said dust container, series of markings visible on the exterior of said vacuum cleaner relative to said member which visually indicate the amount of filling of said dust container at any given time, said attachment plate having at least one through hole through which said first air channel communicates with the interior of said dust container, said through hole being spaced from the inlet opening in said attachment plate, and a portion of said air pervious part being in the air flow path from the interior of said dust container to said first channel, said portion of the air pervious part of the dust containter being folded inwardly toward said inlet opening, said hole being located above said folded-in portion, and said portion forming an abutment surface with the undersurface of said attachment plate.