Patent 7520454 was granted and assigned to WILO on April, 2009 by the United States Patent and Trademark Office.
The invention relates to a cutting tool pertaining to a centrifugal pump for liquids loaded with solids. Said cutting tool comprises a rotating cutting body comprising at least one opening forming a cutting edge and through which the liquid flows, the lateral surface of the cutting body facing the rotationally fixed opposite surface that also comprises at least one opening through which the liquid flows. The lateral surface of the cutting body, facing the opposite surface, is curved in a convex manner, and the opposite surface is curved in a correspondingly concave manner.