Centrifugal basket

Claim 1

A CENTRIFUGAL BASKET CONSTITUTED BY A UNITARY METAL WALL OF FRUSTO-CONICAL FORM AND A PERFORATED SCREEN OF COMPLEMENTARY FORM OVERLYING THE INNER SURFACE OF SAID WALL, SAID WALL HAVING A MULTIPLICITY OF ANNULAR GROOVES RECESSED CIRCUMFERENTIALLY IN SAID INNER SURFACE TO A DEPTH SUFFICIENT TO RECEIVE AND DRAIN OFF LIQUID FILTERED THROUGH SAID SCREEN, SAID GROOVES BEING SEPARATED FROM ONE ANOTHER BY CIRCUMFERENTIAL RIBS INTEGRAL WITH SAID WALL AND THE TOPS OF WHICH DEFINE ELEMENTS OF A COMMON CONICAL SURFACE AND ARE SUFFICENTLY CLOSELY SPACED APART TO SUPPORT SAID SCREEN AGAINST THE LOADS AND CENTRIFUGAL FORCE APPLIED TO IT DURING ROTATION OF THE BASKET, SAID WALL FURTHER HAVING DRAIN HOLES EXTENDING THERETHROUGH, EACH OF SAID DRAIN HOLES BEING CUT THROUGH ONLY ALTERNATE RIBS SO AS TO COMMUNICATE WITH AND LEAD LIQUID RADIALLY AWAY FROM THE GROOVES ADJACENT EACH OF SAID ALTERNATE RIBS, SAID DRAIN HOLES BEING ARRANGED IN CIRCUMFERENTIAL TIERS EXTENDING ALONG EACH OF SAID ALTERNATE RIBS OF SAID WALL, THE RIBS BETWEEN EACH TWO OF SAID ALTERNATE RIBS BEING UNBROKEN AND FREE OF DRAIN HOLES TO PREVENT LIQUID FILTERED THROUGH SAID SCREEN INTO SAID GROOVES FROM CLIMBING ALONG THE INNER SURFACE OF THE WALL, THE DRAIN HOLES IN EACH OF SAID TIERS BEING STAGGERED CIRCUMFERENTIALLY WITH RESPECT TO THE DRAIN HOLES OF THE NEXT ADJACENT TIERS TO DISPOSE THE DRAIN HOLES OF ALTERNATE TIERS IN ROWS EXTENDING ALONG GENERATRICES OF SAID FRUSTO-CONICAL WALL, WHEREBY ALL OF SAID GROOVES COMMUNICATE WITH DRAIN HOLES AND UNDUE WEAKENING OF SAID WALL BY SAID DRAIN HOLES IS AVOIDED.