Intelligent filter construction for electrical appliances, in particular drying/washing-drying machines, method for making the construction, and method for detecting in real time a partial or total clogging of the construction and a value of residual moisture for optimizing the operating cycle of the appliance

A method for detecting in real time a partial and/or complete clogging of a filter construction arranged in a household drying machine for separating solid particles from an air flow in the drying machine, said method comprising at least the steps of:

• providing said filter construction consisting of:
• a synthetic monofilament fabric material of a weft and warp type, said synthetic monofilament fabric material having a mesh opening size between 35 μm to 200 μm;
• and a flat capacitive moisture sensor forming an electrically conductive-capacitive pattern adapted to measure in real time the values of a moisture contained in said air flow passing through said synthetic monofilament fabric material, said electrically conductive pattern having a flat configuration applied on said synthetic monofilament fabric material and consisting of first and second end rectilinear conductive track elements, forming two capacitor plates and from each of which respectively extend a first and a second plurality of rectilinear and parallel mutually spaced conductive finger elements, the finger elements of said first plurality being operatively interdigitated with the corresponding finger elements of said second plurality, said electrically conductive-capacitive pattern covering only a corner portion of said synthetic monofilament fabric material;
• providing an average calibrating curve of said household drying machine;
• detecting and measuring in real time an actual value of residual moisture in an air flow passing through said filter construction at said flat capacitive moisture sensor;
• comparing in real time said actual value of residual moisture with said average calibrating curve;
• generating an alarm signal when said actual value of residual moisture exceeds a preset threshold value;
• and
• removing said clogging from said filter construction only when said preset threshold value is exceeded.