The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 24, 2002
Filed:
Jan. 03, 2001
Roger C. Walsh, Belleville On., CA;
Other;
Abstract
An improved cutting filament for use in a rotary trimmer is an extruded resin, being subject to vertical extrusion to sustain true-section profile, and to structural orientation to enhance the strength and toughness of the material. One embodiment, a polygonal extruded section is drawn down in size, being found to possess improved abrasive, herbiage-cutting characteristics. One embodiment has a finned profile with at least one fin in the form of a projecting rib, preferably with a scarified surface, to enhance its abrasive characteristics. In a polygonal section, the fin portions of the section are located at the apices of the polygon. The draw-down molecular orientation process enables the use of an extrusion die of sufficient size that the scarified finning provision is readily incorporated into the die. A mix of plastic resins consisting of 20 to 40 percent by weight of linear low density, or high density polyethylene, with the balance (75-80%) being polypropylene extrudes as a pliable, high strength, impact and abrasion resistant copolymer filament of adequate High Heat Resistance (HHR) to withstand use as a trimmer filament.