Anzeigevorrichtung für den Verschmutzungsgrad eines von einem Fluid, insbesondere von Luft, durchströmten Filters

摘要

An indicator 1 of the degree of soiling of a filter 4 used in vacuum cleaners through which a fluid, in particular air, flows has a pivotable rocker 10 disposed downstream, in the flow direction, 5 of the filter 4 whose one arm 12 engages into the stream cross section, the pivot position of the rocker 10 being capable of determination via the other arm 13. The fluid passing through the filter engages the easily movable rocker via the arm interacting with the stream cross section to deflect same. This deflection is larger, the larger the torque acting on the arm which, for its part, has a magnitude which depends on the pressure of the air flowing through the filter. The air pressure behind the filter is determined by the degree of soiling of the filter. The more soiled and therefore non-transparent the filter is, the lower the pressure of the passed fluid and therefore the less the deflection of the rocker. In an alternative embodiment (FIG (3(a)) the indicator consists of a tube (215).