Coiled filter having uniform surface porosity

Claim 1

A COILED FILTER COMPRISING A GENERALLY CYLINDRICAL FRAMEWORK HAVING SPACED, COAXIAL, CYLINDRICAL TERMINAL MEMBERS AND A PLURALITY OF SPACED, CIRCULARLY ARRANGED, PARALLEL RIBS, RIGIDLY INTERCONNECTING SAID TERMINAL MEMBERS, SAID RIBS HAVING GRADUALLY WIDENED ENDS AND ADJOINING EACH OTHER SHARPLY-ANGULARLY AT THEIR JUNCTURES WITH SAID TERMINAL MEMBERS IN THE FORM OF POINTED ARCHES, THE SPACING BETWEEN SAID RIBS BEING SUBSTANTIAL TO PROVIDE RELATIVELY WIDE FILTERING AREAS THEREBETWEEN, THE FRAMEWORK BEING FORMED WITH AN EXTERNAL HELICAL GROOVE EXTENDING INTO SAID TERMINAL MEMBERS AND ABOUT SAID RIBS, AND A WINDING OF FINE WIRE DISPOSED UNDER TENSION IN SAID HELICAL GROOVE WITH ITS OPPOSITE ENDS EXTENDING ABOUT SAID TERMINAL MEMBERS; THE TURNS OF SAID GROOVE BEING SO SPACED AS TO MAINTAIN THE TURNS OF WIRE THEREIN SPACED FROM EACH OTHER TO AN EXTENT LESS THAN THE SIZE OF PARTICLES TO BE PREVENTED FROM PASSING THEREBETWEEN AND BEING UNIFORMLY SPACED FROM EACH OTHER FORM AN AREA AT SAID GRADUALLY WIDENED RIB-ENDS, OVER THE POINTS OF SAID ARCHES, AND INT ADJACENT AREAS OF SAID TERMINAL MEMBERS; AND THE WIRE WINDING BEING IN GENERALLY POLYGONAL FORM AT INTERMEDIATE POINTS OF SAID RIBS AND BEING GRADUATED IN FORM FROM SAID INTERMEDIATE POINTS TO THE POINTS OF SAID POINTED ARCHES, WHENCE THE WINDING CONTINUES INTO SAID TERMINAL MEMBERS, IN CYLINDRICAL FORM, WITHOUT INTERRUPTION IN THE UNIFORM SPACING OF THE TURNS OF WIRE OF THE WINDING AT THE POINTS OF SAID ARCHES.