US Patent 7406770 Trimmer with cooperating cutter blades

A trimmer having first and second cutting blades. The first and second cutting blades are mounted so that first and second flat surfaces, respectively thereon, face and are substantially parallel to each other. A drive causes at least one of the first and second cutting blades to move relative to the other of the first and second cutting blades. At least one fastening assembly has first and second facing shoulders between which the first and second cutting blades reside. The at least one fastening assembly further has at least one biasing element that produces a force that biasably urges the first and second flat cutting blade surfaces towards each other.