Electrostatic filter for cleaning dielectric fluids

Claim 1

A FILTER FOR REMOVING SUSPENDED PARTICLES FROM A STREAM OF FLUID, COMPRISING IN COMBINATION: A HOLLOW SHELL HAVING SPACED INLET AND OUTLET OPENINGS FOR THE FLUID STREAM; FILTER MEANS INSIDE THE SHELL COMPRISING A PAIR OF PARALLEL ELECTRODES SPACED APART TO PERMIT FLUID FLOW BETWEEN THEM AND A BODY OF POROUS DIELECTRIC MATERIAL FILLING THE SPACE BETWEEN THE ELECTRODES AND THROUGH WHICH THE FLUID FLOWS; MEANS FOR ESTABLISHING AN ELECTRIC POTENTIAL BETWEEN SAID PAIR OF ELECTRODES TO MAINTAIN AN ELECTRO-STATIC FIELD BETWEEN THE PAIR OF ELECTRODES; MEANS FOR INTRODUCING FLUID TO THE FILTER MEANS NEAR ONE EDGE OF THE ELECTRODES, THE FLUID FLOWING AWAY FROM SAID EDGE AND TOWARD A REMOTE EDGE OF THE ELECTRODES THROUGH THE BODY OF POROUS DIELECTRIC MATERIAL THROUGH A PASSAGE BETWEEN THE ELECTRODES, SAID PASSAGE BEING OF PROGRESSIVELY INCREASING CROSS-SECTIONAL AREA IN THE DIRECTION OF FLUID FLOW.