Abstract: Apparatus for sharpening a cutting tool. In some embodiments, a powered sharpener has a main drive assembly with an electric motor, and a sharpening assembly with belt support surfaces to provide a routing path for the belt to define first and second belt segments. A first blade guide is configured to position a blade of the cutting tool at a first guide angle to sharpen a cutting edge of the blade against the first belt segment. A second blade guide is configured to position the blade at a second guide angle to sharpen the cutting edge of the blade against the second belt segment. The first and second belt segments may be parallel or non-parallel. As desired, anti-torsion members may be provided to contactingly engage a backing layer of the belt to resist torsional twisting of the belt during sharpening against the first and second belt segments.

Abstract: A tool sharpener has a guide assembly to support a cutting tool adjacent an abrasive medium. A drive assembly advances the abrasive medium with respect to the guide assembly. A control mechanism provides a first control input value to move the medium and achieve a first material take off (MTO) rate during a coarse sharpening operation upon the tool. A second control input value from the control circuit moves the medium to achieve a lower, second MTO rate during a fine sharpening operation. The control mechanism transitions the medium from the first MTO rate to the second MTO rate responsive to a timer mechanism indicating a conclusion of a predetermined elapsed time interval.

Abstract: Apparatus and method for sharpening a cutting tool so as to have enhanced cutting performance. In some embodiments, a tool sharpener is provided having a rigid body with a slot extending therein. A knurl roller is disposed within an internal cavity within the rigid body and mounted for rotation about a selected axis adjacent the slot to facilitate a cold forging operation upon a cutting edge of a cutting tool via insertion of the cutting edge into the slot and retraction of the cutting tool across the knurl roller. An abrasive member is affixed to the rigid body to facilitate a sharpening operation upon the cutting edge by advancement of the cutting edge thereacross.

Abstract: Method and apparatus for sharpening a cutting tool. In some embodiments, an abrasive endless belt is rotated in tension along a neutral plane between spaced apart first and second rollers. A guide assembly has spaced apart first and second guide surfaces which collectively converge to an intervening base surface to form a guide channel. Upon insertion of a blade of a cutting tool into the guide channel, a selected side of the blade contactingly slides against at least a selected one of the first or second guide surfaces and a first portion of a cutting edge of the blade contactingly engages the base surface to serve as a plunge depth limit stop for the blade. The endless belt is contactingly deflected by a second portion of the cutting edge away from the neutral plane to sharpen the second portion while the first portion remains in contact with the base surface.

Abstract: Method and apparatus for sharpening a cutting tool having a blade portion with a cutting edge, such as but not limited to a kitchen knife. In some embodiments, a powered sharpener has an abrasive medium that is advanced by a motor and an edge guide surface adjacent the abrasive medium, wherein the cutting edge of the cutting tool is sharpened by bringing a first portion of the cutting edge into contacting engagement with the edge guide surface and drawing a second portion of the cutting edge across the abrasive medium. A plurality of spaced apart channels are formed in the sharpened cutting edge by contactingly engaging the sharpened cutting edge with a cold forging member with sufficient force to displace portions of the sharpened cutting edge. The channels in the sharpened cutting edge constitute locally deformed, work hardened notches.

Abstract: Method and apparatus for sharpening a cutting tool. In some embodiments, an abrasive endless belt is rotated in tension along a neutral plane between spaced apart first and second rollers. A guide assembly has spaced apart first and second guide surfaces which collectively converge to an intervening base surface to form a guide channel. Upon insertion of a blade of a cutting tool into the guide channel, a selected side of the blade contactingly slides against at least a selected one of the first or second guide surfaces and a first portion of a cutting edge of the blade contactingly engages the base surface to serve as a plunge depth limit stop for the blade. The endless belt is contactingly deflected by a second portion of the cutting edge away from the neutral plane to sharpen the second portion while the first portion remains in contact with the base surface.

Abstract: A multi-stage hand-held sharpener. In some embodiments, the sharpener has a handle adapted to be gripped by a hand of a user, the handle extending along a longitudinal axis between opposing first and second ends. A primary sharpening stage is provided in the handle between the first and second ends, the primary sharpening stage having a first abrasive surface extending at a first angle to facilitate a primary sharpening operation by a user upon the tool. An abrasive rod extends from the first end of the handle in a direction parallel to the longitudinal axis. The handle includes a substantially flat guide surface linearly extending from the first end toward the abrasive rod at a second angle, the abrasive rod and the guide surface forming a second sharpening stage adapted to facilitate a secondary sharpening operation by the user upon the tool.

Abstract: A multi-rod hand-held sharpener. In some embodiments, the sharpener has a handle with opposing first and second ends, an outer grip surface, and a guide surface adjacent the first end extending at a selected angle with respect to a central axis. A first abrasive rod is adapted to extend from the first end of the handle in a selected direction parallel to the central axis and having a first outer abrasive surface with a first abrasiveness level, the first outer abrasive surface extending at a first non-orthogonal angle with respect to the guide surface. A second abrasive rod is adapted to extend from the first end of the handle in the selected direction and having a second outer abrasive surface with a different, second abrasiveness level. The second outer abrasive surface extends at a different, second non-orthogonal angle with respect to the guide surface.

Abstract: Apparatus for sharpening a cutting tool. In some embodiments, a tool sharpener includes an abrasive medium having an abrasive surface. A stationary tool support guide provides a guide surface that supports a side of the tool during presentation of a cutting edge of the tool against the abrasive surface. A rotatable edge guide has a roller member with a curvilinearly extending outer surface. The roller member is rotatable about an edge guide roller axis and is moveable between a deployed position and a retracted position. In the deployed position, the roller member is positioned to engage, via rolling contact, the cutting edge during the presentation of the cutting edge against the abrasive surface. In the retracted position, the roller member is positioned to provide a non-contacting clearing relation with the cutting edge during said presentation.

Abstract: Method and apparatus for sharpening a cutting tool. In some embodiments, a sharpener has a guide assembly adjacent a moveable abrasive medium. The medium is advanced at a first speed relative to the guide assembly during a coarse sharpening operation in which a user presents the cutting tool against the medium to shape a side of the cutting tool and generate distended material from the cutting edge (e.g., burrs). The medium is subsequently slowed to a lower, second speed for a fine sharpening operation in which the user presents the cutting tool against the medium to remove the distended material and provide a sharpened cutting edge.

Abstract: A sharpener for sharpening a cutting tool having a blade portion with a cutting edge, such as but not limited to a kitchen knife. In some embodiments, the sharpener has first and second rollers, with the first roller rotatable about a first roller axis and the second roller rotatable about a second roller axis parallel to the first roller axis. An endless abrasive belt is arranged along a belt path that passes over the first and second rollers to define a planar segment that lies along a neutral plane from the first roller to the second roller. A guide assembly adjacent the planar segment of the belt is configured to contactingly engage the cutting edge of the cutting tool and apply a non-uniform surface pressure to a side of the cutting tool adjacent the cutting edge across a width of the belt.

Abstract: Apparatus and method for sharpening a tool. In accordance with some embodiments, a selected side surface of the tool is placed in contacting engagement against an upper reverse sharpening guide surface that faces an abrasive surface extending along a first plane. The upper reverse sharpening guide surface is aligned along a second plane that intersects the first plane at an acute angle. A tool cutting edge contactingly engages a non-abrasive support surface disposed between the upper reverse sharpening guide surface and the abrasive surface to establish a plunge depth of the tool prior to contact with the abrasive surface. The tool is thereafter moved away from the upper reverse sharpening guide in a lateral direction across the abrasive surface while nominally maintaining the tool at the acute angle to sharpen the cutting edge in a trailing cutting edge orientation.

Abstract: Method for sharpening a cutting tool. In some embodiments, a first abrasive belt is advanced along a belt path between first and second rollers. A cutting tool inserted into a v-shaped slot is drawn across the belt as a cutting edge is supported by a limit stop of the slot. The first abrasive belt is deflected at a first radius of curvature in relation to a first linear stiffness of the belt and a tension applied to the first roller. The first abrasive belt is replaced with a second abrasive belt, and the cutting tool is again inserted into the v-shaped slot and drawn across the belt as the cutting edge is supported by the limit stop of the slot. The second abrasive belt is deflected at a second radius of curvature in relation to a second linear stiffness of the belt and the tension applied to the first roller.

Abstract: Apparatus for sharpening a cutting tool. In some embodiments, a tool sharpener is provided with a flexible abrasive medium having an abrasive surface and arranged along a planar extent. A guide assembly has a guide frame, a cam surface, and a pivotal guide member. A guide surface on the guide member extends at a selected angle with respect to the planar extent of the medium to support a first side of the tool during presentation of a second side and cutting edge of the tool against the abrasive surface along the planar extent. A cam follower contactingly engages the cam surface to establish the selected angle. A biasing mechanism applies a biasing force to urge the guide surface to pivot toward the planar extent to maintain the cam follower in contact with the cam surface.

Abstract: Apparatus and method for sharpening a cutting tool, such as but not limited to a kitchen knife. In accordance with some embodiments, a flexible abrasive disk is adapted for rotation about a central axis at a selected rotational velocity. Centrifugal forces imparted to the disk during rotation urge the disk to a neutral position in which an outer peripheral portion of the disk is extended toward a selected plane. A housing adjacent the flexible disk has a guide slot with a guide surface at a selected bevel angle with respect to the selected plane. The guide surface is adapted to facilitate presentation of a cutting tool in contacting engagement against the disk. The cutting tool is presented at the selected bevel angle to induce curvilinear displacement of the flexible disk during sharpening of a cutting edge that extends along a side of the cutting tool.

Abstract: Apparatus and method for sharpening a cutting tool having a cutting edge. In some embodiments, a manual sharpener includes a base housing adapted to be contactingly supported on a base surface, with the base housing having an overall length dimension in a first direction. A support member extends along the overall length dimension of the base housing and is adapted for rotation with respect to the base housing about a central axis extending along the first direction. An abrasive surface covers a top surface of the support member. The support member rotates the abrasive surface responsive to presentation of the cutting edge of the tool thereagainst as the cutting edge is moved along the abrasive surface in the first direction. A biasing mechanism coupled to the support member urges the support member to a neutral rotational position with respect to the base housing.

Abstract: Apparatus for sharpening a cutting tool. In some embodiments, a tool sharpener includes an abrasive medium having an abrasive surface. A stationary tool support guide provides a guide surface that supports a side of the tool during presentation of a cutting edge of the tool against the abrasive surface. A rotatable edge guide has a roller member with a curvilinearly extending outer surface. The roller member is rotatable about an edge guide roller axis and is moveable between a deployed position and a retracted position. In the deployed position, the roller member is positioned to engage, via rolling contact, the cutting edge during the presentation of the cutting edge against the abrasive surface. In the retracted position, the roller member is positioned to provide a non-contacting clearing relation with the cutting edge during said presentation.

Abstract: A multi-stage hand-held sharpener includes a handle with an outer grip surface, and a first sharpening stage incorporated into the handle having a first abrasive surface. The first sharpening stage is adapted to facilitate a primary sharpening operation by a user upon a tool responsive to the user contactingly advancing a cutting edge of the tool against the first abrasive surface. A second sharpening stage includes a guide surface which extends in a non-orthogonal direction adjacent a second abrasive surface to establish a reference angle. The second sharpening stage facilitates a secondary sharpening operation by the user upon the tool responsive to the user contactingly engaging a side of the tool with the guide surface to orient the tool at said reference angle, and advancing a cutting edge of the tool against the second abrasive surface while maintaining the tool at said presentation angle.

Abstract: A multi-rod hand-held sharpener includes a handle with an outer grip surface for a hand of a user, a first abrasive rod having a first outer abrasive surface with a first abrasiveness level, and a second abrasive rod having a second outer abrasive surface with a second abrasiveness level different from the first abrasiveness level. At least one guide surface extends toward the first sharpening surface at a selected guide angle non-orthogonal to the first sharpening surface. The user contactingly engages a side of the tool against the guide surface and a cutting edge of the tool against the first abrasive surface, and then advances the side of the tool away from the guide surface and the cutting edge against the first abrasive surface while maintaining the tool at the selected guide angle. An optional second guide adjacent the second abrasive surface at a different angle facilitates micro-beveling.