# US 5,700,189 A · Knife-blade sharpening apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,700,189 A - Document ID: US5700189A - Status: Granted - Kind: A - Application number: 08/678,578 - Filed: 1996-07-08 - Granted: 1997-12-23 - Earliest claimed: 1996-07-08 - Inventors: Jimmie L. Farris - Web page: https://patentgrep.com/patent/US5700189A ## CPC - B24D 15/08: of knives; of razors - B24D 15/06: specially designed for sharpening cutting edges - B24D: TOOLS FOR GRINDING, BUFFING OR SHARPENING (abrading-bodies specially designed for tumbling apparatus, e.g. abrading-balls B24B31/14; honing tools B24B33/08; lapping tools B24B37/11) ## Abstract A blade-sharpening apparatus for knives and other cutting tools which uses a ceramic sharpening element. The sharpening element is a recycled aluminum oxide sodium vapor streetlight bulb. The vapor and heat expansion and contraction of the bulb during use as a light causes wear on the bulb and results in the ceramic element becoming more porous, thereby providing an abrasive surface suitable for blade sharpening. A first embodiment of the apparatus comprises a housing with a support substantially along a length of the sharpening element and a cover for enclosing the sharpening element when not in use. In the first embodiment, the sharpening element is supported on both ends. In a second embodiment, the sharpening element is supported on one end by a handle and a sleeve is provided to enclose the sharpening element when not in use. The sleeve may be attached to a portion of the handle opposite the sharpening element when in an operating position. ## Claims ### Claim 1 A blade-sharpening apparatus comprising: a sharpening element comprising a ceramic tube subjected to heat expansion and contraction cycles such that the surface thereof is made porous; and support means for supporting said sharpening element during a sharpening operation in which a blade is moved across an outer surface of the sharpening element. ### Claim 2 (depends on 1) The apparatus of claim 1 wherein said ceramic tube is a recycled streetlight bulb. ### Claim 3 (depends on 2) The apparatus of claim 2 wherein said bulb is a sodium vapor bulb. ### Claim 4 (depends on 1) The apparatus of claim 1 wherein said tube is substantially cylindrical. ### Claim 5 (depends on 1) The apparatus of claim 1 wherein said support means is engaged with at least one end of said sharpening element. ### Claim 6 (depends on 1) The apparatus of claim 1 wherein said support means provides support along a substantial length of an outer surface of the sharpening element. ### Claim 7 (depends on 6) The apparatus of claim 6 further comprising a housing having a base portion, wherein said support means extends from said base portion. ### Claim 8 (depends on 7) The apparatus of claim 7 wherein said support means and base portion are integrally formed. ### Claim 9 (depends on 7) The apparatus of claim 7 wherein: said base portion has a housing end extending therefrom, said housing end defining an opening therein; and an end of said sharpening element is disposed in said opening in said housing end. ### Claim 10 (depends on 9) The apparatus of claim 9 wherein said housing end of said housing is one of a pair of housing ends; and said cover means is characterized by a cover extending longitudinally between said housing ends. ### Claim 11 (depends on 1) The apparatus of claim 1 wherein: said support means is characterized by a handle defining an opening in an end thereof; and a proximate end of said sharpening element is disposed in said opening in said handle. ### Claim 12 (depends on 11) The apparatus of claim 11 wherein said cover means is characterized by a sleeve disposed around said sharpening element. ### Claim 13 (depends on 12) The apparatus of claim 12 wherein said sleeve is adapted for tightly fitting engagement with a portion of said handle adjacent to said sharpening element when in a closed position. ### Claim 14 (depends on 12) The apparatus of claim 12 wherein said sleeve is adapted for tightly fitting engagement with a portion of said handle opposite said sharpening element when in an operating position. ### Claim 15 A blade-sharpening apparatus comprising: a handle; and an elongated sharpening element engaged with said handle, said sharpening element comprising a ceramic light bulb subjected to heating and cooling cycles such that the surface thereof is roughened. ### Claim 16 (depends on 15) The apparatus of claim 15 further comprising a sleeve disposable around said sharpening element and engagable with said handle such that said sharpening element is substantially enclosed when said sleeve is in a closed position. ### Claim 17 (depends on 16) The apparatus of claim 16 wherein said sleeve is engagable with an opposite end of said handle from said sharpening element when in an operating position. ### Claim 18 (depends on 15) The apparatus of claim 15 wherein said sharpening element is substantially cylindrical. ### Claim 19 A blade-sharpening apparatus comprising: a housing comprising: a base portion having a surface thereon; and a pair of spaced ends extending from said base portion, each of said ends defining an opening therein; a support disposed along said surface of said base position between said ends; and a sharpening element disposed on said support such that opposite longitudinal ends of said sharpening element are disposed in said openings in said ends of said housing, said sharpening element comprising a ceramic light bulb subjected to heating and cooling cycles such that the surface thereof is roughened. ### Claim 20 (depends on 19) The apparatus of claim 19 wherein: said support defines a groove therein having an arcuate cross section; and said sharpening element is substantially cylindrical and adapted for engaging said groove in said support. ### Claim 21 (depends on 19) The apparatus of claim 19 wherein said support and said base portion are integrally formed. ### Claim 22 (depends on 19) The apparatus of claim 19 further comprising a cover disposable between said ends of said housing and adapted for enclosing said sharpening element when in a closed position. ### Claim 23 (depends on 15) The apparatus of claim 15 wherein said light bulb is a sodium vapor bulb. ### Claim 24 (depends on 15) The apparatus of claim 15 wherein said ceramic light bulb is formed of aluminum oxide. ### Claim 25 (depends on 19) The apparatus of claim 19 wherein said light bulb is a sodium vapor bulb. ### Claim 26 (depends on 19) The apparatus of claim 19 wherein said ceramic light bulb is formed of aluminum oxide.