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:
Apr. 23, 1991
Filed:
Aug. 17, 1990
Cvetan Petroff, Kew, AU;
McPherson's Limited, , AU;
Abstract
A blade sharpener having a sharpening mechanism which functions to sharpen a blade engaging that mechanism and being moved longitudinally relative thereto. The sharpener also includes sharpening defeating means which, when operative, at least inhibits and possibly prevents sharpening of a blade by the sharpening mechanism when that blade is moved longitudinally through the sharpener in one direction. The defeating means is responsive to blade movement so as to adopt an operative condition when the blade is moved in the aforementioned one direction, and to adopt an inoperative condition when the blade is moved through the sharpener in the opposite direction. The defeating means includes a blade engaging member such as a roller, and in the operative condition that roller engages and presses against the cutting edge of the blade so as to impose a force on the blade which acts counter to the force causing the blade to engage the sharpening mechanism. The counter force therefore tends to push the blade out of contact with the sharpening mechanism. The roller does not engage the blade, or at least does not apply the counter force, when the defeating means is in the inoperative condition. An anti-bottoming groove is provided around the circumferential surface of the roller to provide a location for the cutting edge of the knife blade and that groove is formed to avoid contact between the actual cutting edge of the blade and the base of the groove.