Filtering apparatus

Claim 1

FILTERING APPARATUS COMPRISING: MEANS FOR CONTAINING A LIQUID CARRYING ENTRAINED SOLIDS; MEANS DEFINING A COLLECTING SPACE; MEANS FORMING A FIRST PATH FOR CONDUCTING LIQUID FROM SAID CONTAINING MEANS TO SAID SPACE AND HAVING AN INLET OPENING TO SAID CONTAINING MEANS AND A PRELIMINARY FILTER ACROSS SAID INLET; MEANS FORMING A SECOND PATH FOR CONDUCTING LIQUID FROM SAID CONTAINING MEANS TO SAID SPACE IN PARALLEL WITH SAID FIRST PATH AND HAVING AN INLET WHICH OPENS TO SAID CONTAINING MEANS FOR RECEIVING THE LIQUID CARRYING ENTRAINED SOLIDS FROM THE CONTAINING MEANS INCLUDING LIQUID FLOWED OVER SAID PRELIMINARY FILTER TO WASH SOLIDS FILTERED FROM THE LIQUID FLOWED IN SAID FIRST PATH AND COLLECTED ON SAID FILTER INTO SAID SECOND PATH MEANS INLET, SAID SECOND PATH MEANS FURTHER INCLUDING A SECONDARY FILTER THEREACROSS SPACED FROM SAID SECOND PATH MEANS INLET AND DEFINING THEREBETWEEN A FILTER CHAMBER PORTION, AND FORAMINOUS PRESSURE DROP MEANS BETWEEN SAID SECONDARY FILTER AND SAID COLLECTING SPACE FOR REDUCING THE VELOCITY OF LIQUID FLOW THROUGH THE SECONDARY FILTER THEREBY TO PREVENT EXCESSIVE WEDGING OF FILTERED SOLIDS INTO SAID SECONDARY FILTER, SAID SECONDARY FILTER MEANS DEFINING THE SMALLEST SIZE OPENINGS IN SAID SECOND PATH THEREBY SUBSTANTIALLY PRECLUDING FILTERING BY SAID PRESSURE DROP MEANS; AND MEANS FOR SELECTIVELY CAUSING FLOW OF LIQUID THROUGH SAID CHAMBER OVER SAID FILTER TO A DRAIN OUTLET THEREBY TO SELECTIVELY WASH THE RETAINED FILTERED SOLIDS FROM THE SECONDARY FILTER.