Dust and liquid detector

Claim 1

A DEVICE ADAPTED TO BE MOUNTED OVER AN APERTURE IN A CONDUIT FOR DETECTING SOLID OR LIQUID PARTICLES CARRIED IN GAS FLOWING THROUGH SUCH CONDUIT, THE COMBINATION OF: A FRAME FOR FITTING OVER THE CONDUIT APERTURE AND BEING SECURED TO THE CONDUIT, SAID FRAME HAVING AN ELEMENT EXTENDING THROUGH SAID CONDUIT APERTURE A SMALL DISTANCE INTO THE CONDUIT, SAID FRAME AHVING AN APERTURE ADJACENT SAID ELEMENT, A TRANSPARENT MEMBER SEALABLY ENGAGING SAID FRAME AND CLOSING THE SAID FRAME APERTURE, A CAP HAVING A CENTRAL APERTURE AND POSITIONED OVER SAID TRANSPARENT MEMBER, MEANS SECURING SAID CAP TO SAID FRAME TO RELEASABLY SECURE SAID TRANSPARENT MEMBER TO SAID FRAME IN SEALING RELATION, SAID ELEMENT HAVINGA FLAT SURFACE EXTENDING AT AN ANGLE TO THE DIRECTION OF GAS FLOW, SAID SURFACE EXTENDING INWARDLY IN AN UPSTREAM DIRECTION AND BEING VISIBLE THROGH SID TRANSPARENT MEMBER WHEREBY SOME OF THE FLOWING GAS IS DIVERTED BY SAID SURFACE OF THE ELEMENT TOWARD SAID TRANSPARENT MEMBER TO CAUSE SOME OF THE PARTICLE TO COME TO REST AT LEAST MOMENTARILY ON SAID SURFACE AND SAID TRANSPARENT MEMBER AND ARE OBSERVABLE THROUGH SAID TRANSPARENT MEMBER.