OPTICAL SENSOR FOR DETECTING THE LIQUID LEVEL IN A CONTAINER, IN PARTICULAR FOR A REMOVABLE CONTAINER FOR AN ELECTRIC HOUSEHOLD APPLIANCE AND ASSOCIATED LENS AND METHOD

摘要

An optical sensor including a photo emitting element (8) and a photo receiving element (9) carried side-by-side by a supporting and feeding element (10) either associated or associable in use with a support (5) for a container (3), and a composite lens (11), either associated or associable with the container (3), designed so as to remain in use immersed in a liquid (2) contained in the container and facing the photo emitting and photo receiving elements (8,9); the lens including: a first cylindrical body (150) made of a light -permeable material, mountable in use vertically from the top of the container (3) facing the photo emitting and photo receiving elements to a bottom wall (18) of the container; and a second cylindrical body (19), arranged concentrically with and outside the first body and open towards the bottom wall; respective side walls (21,20) of the first and second cylindrical bodies (150,19) having the same length, that of the second body being separated from that of the first body by a predetermined annular clearance (G), and being made so as to be at least partially reflecting towards the first cylindrical body (150).