Selectively deployable rotatable edge guide to support a cutting tool during a sharpening operation

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.

BACKGROUND

Cutting tools are used in a variety of applications to cut or otherwise remove material from a workpiece. A variety of cutting tools are well known in the art, including but not limited to knives, scissors, shears, blades, chisels, spades, machetes, saws, drill bits, etc.

A cutting tool often has one or more laterally extending, straight or curvilinear cutting edges along which pressure is applied to make a cut. The cutting edge is often defined along the intersection of opposing surfaces that intersect along a line that lies along the cutting edge.

Cutting tools can become dull over time after extended use. It can thus be desirable to subject a dulled cutting tool to a sharpening operation to restore the cutting edge to a greater level of sharpness. A variety of sharpening techniques are known in the art, including the use of grinding wheels, whet stones, abrasive cloths, etc. While these and other sharpening techniques have been found operable, there is a continued need for improvements in the manner in which various cutting tools may be sharpened.

SUMMARY

Various embodiments of the present disclosure are generally directed to an apparatus for sharpening a cutting edge of a tool.

In some embodiments, a tool sharpener is provided with an abrasive medium having an abrasive surface. A stationary tool support guide has a guide surface that extends along a guide plane at a selected angle with respect to the abrasive surface. The guide surface contactingly supports a side of the tool during presentation of a cutting edge of the tool against the abrasive surface. A rotatable edge guide adjacent the stationary tool support 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 contactingly engage 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.

In related embodiments, the tool sharpener has a base structure which encloses an electric motor. An abrasive medium is supported by the base structure and adapted for rotational movement responsive to the electric motor, the abrasive medium having an abrasive surface extending along a neutral plane. A stationary tool support guide has a guide surface extending along a guide plane at a selected angle with respect to the neutral plane to engage, via sliding contact, a side of the tool during presentation of a cutting edge of the tool against the abrasive surface. A rotatable edge guide adjacent the stationary tool support guide has a roller member having a curvilinearly extending outer surface rotatable about an edge guide roller axis. The rotatable edge guide is rotatable about an edge guide central axis between a deployed position and a retracted position. In the deployed position, the roller member is a first distance from the guide surface to facilitate rolling support of the cutting edge during said presentation. In the retracted position, the roller member is a second distance from the guide surface greater than the first distance to provide a non-contacting, clearing relation with the cutting edge during said presentation.

In further related embodiments, the tool sharpener has an endless abrasive belt with an abrasive surface. The belt is over a belt roller and placed under tension to present a planar extent of the belt adjacent the roller, the roller rotatable about a first axis. A stationary tool support guide has a guide surface extending along a guide plane at a selected angle with respect to the planar extent of the belt to engage, via sliding contact, a side of the tool during presentation of a cutting edge of the tool against the abrasive surface of the belt. A rotatable edge guide adjacent the stationary tool support guide includes a roller member having a curvilinearly extending outer surface rotatable about a second axis orthogonal to the first axis to engage, via rolling contact, the cutting edge during said presentation of the cutting edge against the abrasive surface.

These and other aspects of various embodiments of the present disclosure will become apparent from a review of the following detailed description in conjunction with the accompanying drawings.

DETAILED DESCRIPTION

FIG. 1shows an exemplary tool sharpener100constructed in accordance with some embodiments of the present disclosure. The tool sharpener100is configured to sharpen a variety of tools with different configurations of cutting edges. Top and front side views of the tool sharpener100are provided inFIGS. 2A and 2B. The tool sharpener100is characterized as a hand-held powered sharpener.

The tool sharpener100includes a base structure102which encloses and/or supports various components of interest. The structure102includes a main body104and a sharpening attachment assembly106. The sharpening attachment assembly106can be removably mated with the main body104to facilitate various sharpening operations described below. As desired, other operable attachments (not separately shown) can be installed on the main body104to carry out other motor-driven functions.

The main body104is adapted to be securely placed on a base surface108(FIG. 2B) or, alternatively, to be picked up and supported by a user of the tool sharpener100. A handle110has a user grip surface adapted to be grasped by a hand of the user. A trigger assembly112can be selectively depressed to energize a motor (not separately shown) disposed within the main body104. An electrical power cord (also not separately shown) can extend from an end of the main body104to supply electrical power for use by the sharpener100.

The motor is used to drive an abrasive member114during a sharpening operation. The abrasive member114is characterized as an endless abrasive belt which is routed along a belt path that passes adjacent rollers116A,116B and116C. Other forms of abrasive members can be used in accordance with the present disclosure, including disc shaped abrasive members, non-motor driven abrasive members, etc. It will be noted that the abrasive belt114is supported by, and is located outside of, the base structure102to expose various portions of the belt for sharpening operations and to facilitate easy removal and replacement of the belt.

A spring-biased tensioner assembly118coupled to roller116C applies a tension force to the abrasive member (hereinafter, “belt”)114. This forms two planar extents114A,114B that extend between rollers116A-116B and116A-116C, respectively. The planar extents114A,114B are best viewed inFIG. 2B. The planar extents are nominally maintained along respective neutral planes except when deflected during a sharpening operation through contact with the cutting edge of a tool, as discussed below.

An adjustable sharpening guide assembly120is provisioned adjacent the planar extents114A,114B. The sharpening guide assembly120includes a pair of opposing, stationary sharpening guides122A,122B. The stationary sharpening guides122A,122B have respective guide surfaces124A,124B which extend along respective guide planes at a common, fixed acute angle with respect to the neutral planes of the planar extents114A,114B.

The guide surfaces124A,124B contactingly support the respective side surfaces of a cutting tool during a double-sided sharpening operation as the cutting tool is presented against each guide surface in turn. A cam-based adjustment mechanism can be used to selectively set the guide surfaces124A,124B to the common, fixed acute angle. Angles from about 15 degrees to about 30 degrees can be selected.

A rotatable edge guide is represented generally at130. As further shown inFIGS. 3A and 3B, the rotatable edge guide130is rotatable with respect to the base structure102(in this case, a base support plate132of attachment106) between a deployed position (FIG. 3A) and a retracted position (FIG. 3B). It will be noted that the rotatable edge guide130is shown in the deployed position inFIGS. 1 and 2A, and shown in the retracted position inFIG. 2B.

FIG. 4provides an exploded representation of the rotatable edge guide130in accordance with some embodiments. The rotatable edge guide130includes a central body134which supports opposing roller members136A,136B. The roller members136A,136B are each provided with a curvilinearly extending outer surface. The surfaces are cylindrically shaped inFIG. 4, but other shapes can be used including v-shaped members, etc.

It is contemplated that the roller members136A,136B are formed of a suitable compliant material, such as a non-marring plastic. The use of a compliant material will tend provide a desired level of friction between the roller member and the cutting edge to ensure rotational movement of the roller is established during retraction of the tool. However, other materials can be used including rigid materials such as metal for the roller members.

Shaft fasteners138A,138B secure the roller members136A,136B to the central body134and facilitate independent rotation of the roller members about an edge roller guide axis140.

The central body134is secured to the plate132using shaft fastener142. A biasing member (e.g., coiled spring)144exerts a biasing force upon the central body134to urge the central body in a direction toward the plate132. The shaft fastener142and biasing member144facilitate selective rotation of the central body134about an edge guide central axis146between the deployed position (FIG. 3A) and the retracted position (FIG. 3B).

It will be noted that the edge guide roller axis140is orthogonal to the edge guide central axis146irrespective of the rotational position of the central body134, but this is merely exemplary and not necessarily limiting. It will further be noted that, in the deployed position, the edge guide roller axis140is orthogonal to the roller axes about which each of the belt rollers116A,116B,116C rotate. In the retracted position, however, the edge guide roller axis140is non-orthogonal (skewed) to these roller axes.

Referring again toFIG. 3A, when the rotatable edge guide130is moved to the deployed position, the roller members136A,136B are each positioned to contactingly engage the cutting edge of a cutting tool during respective sharpening operations using the stationary tool support guides122A,122B. The roller members136A,136B rotate about the edge guide roller axis140as the cutting edge is drawn across the associated planar extent114A,114B of the abrasive member114.

When moved to the retracted position, the roller members136A,136B are positioned to provide a non-contacting clearing relation with the cutting edge of the tool during such sharpening operations. The retracted position provides clearance for finger guards or other features that would otherwise mechanically interfere with the presentation of the cutting tool against the abrasive member. It will be noted that at least roller member136A is a first distance from the corresponding guide member122A in the deployed position and a second, greater distance from the guide member122A in the retracted position.

At this point it will be noted that the edge guide130is referred to herein as “rotatable” due to the rotating nature of the roller supports supplied in the deployed position, not necessarily because the edge guide130can be rotated between the deployed and retracted positions. Other translational movement paths, including non-rotational paths (e.g., linear paths, etc.), can be used to transition the rotatable edge guide130between the deployed and retracted positions.

FIGS. 5A and 5Bshow the rotatable edge guide130in greater detail. The central body134includes a planar face plate150to enable a user to grasp and manipulate the rotatable edge guide130. A threaded boss152extends downwardly from the face plate150to threadingly receive the shaft fastener142(FIG. 4). A pair of cam flanges154A,154B (“cams”) flank the boss152and serve as travel and locking features for the rotatable edge guide130.

A transition sequence is illustrated inFIGS. 6A-6Dto show how the rotatable edge guide130can be moved between the deployed and retracted positions. The base structure plate132includes opposing cam surfaces156A-156B with notches158A,158B on opposing sides of the central axis146(seeFIG. 4). Only the cam surface156A and notch158A are visible inFIGS. 6A-6D, but the sequence steps shown therein are concurrently carried out on the opposing second side of the guide using the cam surface156B and the notch158B.

Initially, as shown inFIG. 6Athe notch158A nestingly receives and retains the cam flange154A in the deployed position. This serves as a locking mechanism to retain the edge guide130in the deployed position. To transition the edge guide130to the retracted position, the user grasps the plate150and pulls the central body134away from the base structure plate132so that the cam flange154A is retracted from the notch158A, as depicted inFIG. 6B. This retraction by the user overcomes the bias force applied to the central body134by the biasing member144(FIG. 4).

The user next rotates the central body134about the central axis146(FIG. 4) in the direction shown inFIG. 6C. This allows the cam flange154to contactingly travel along the cam surface156A. As the central body134is rotated, the edge guide130will continuously retract toward the base structure plate132as the cam flange moves along the ramped cam surface.

Finally, as shown inFIG. 6D, upon sufficient rotation and retraction of the central body134, the rotatable edge guide130will be pulled into a full body retention notch160(best viewed inFIG. 4) by the biasing member (spring)144. The sidewalls of the retention notch160will serve as a locking mechanism to lock the rotatable edge guide130in the retracted position. The sequence steps ofFIGS. 6A-6Dare reversed to return the rotatable edge guide130to the deployed position.

FIGS. 7A-7Cdepict a sharpening sequence upon an exemplary cutting tool170using the rotatable edge guide130in the deployed position ofFIG. 6A. The cutting tool is characterized as a kitchen knife with a user grippable handle172and a blade portion174which extends from the handle172. The blade portion174includes opposing first and second side surfaces, only one of which is visible and denoted inFIGS. 7A-7Cat176.

A cutting edge178extends along the length of the blade portion174and is defined along the converging intersection of the opposing side surfaces. A top surface180is provided opposite the cutting edge178. The top surface180remains non-contactingly supported during sharpening using the sharpener100, thereby providing clearance to permit a wide variety of sizes and shapes of tools to be sharpened, as well as accommodating rotational retractional movement of the knife170during sharpening, as will now be described.

To begin the sharpening sequence, as depicted inFIG. 7Aa user grasps the handle172and inserts the blade portion174into the clearance gap between the planar extent114A of the abrasive member114and the guide surface124B. The user lowers the cutting edge178so that a distal end of the cutting edge opposite the handle172contactingly engages the stationary edge guide182and a proximal end of the cutting edge adjacent the handle contactingly engages the rotatable edge guide130. It can be seen fromFIG. 7Athat the abrasive member114extends between the stationary edge guide182and the rotatable edge guide130so that the stationary edge guide182supports the distal end of the cutting edge adjacent a first edge (side)114C of the abrasive member114, while the rotatable edge guide130concurrently supports the proximal end of the cutting edge of the tool adjacent an opposing second edge (side)114D of the abrasive member114.

Concurrently, the knife130is rotated about its longitudinal axis (e.g., length from end of handle to end of blade) as required to bring a portion of the side surface176into contacting planar alignment with the guide surface124B. The abrasive member114can be rotating along its associated belt path during this insertion phase or rotation can be subsequently initiated by the user.

Once aligned, the cutting edge178contactingly engages the planar extent114A of the abrasive member114and relative movement of the abrasive surface adjacent the tool will induce sharpening of the cutting edge. Some deflection of the abrasive member114may occur during such contact, as will be explained below.

As shown byFIG. 7B, the user slowly retracts the knife170along a retraction path (arrow184) while maintaining the side surface176in contacting engagement, via sliding contact, against the guide surface124B. The cutting edge is maintained in contacting engagement, via sliding contact, against the stationary edge guide182, and in contacting engagement, via rolling contact, against the rotatable edge guide130. This sequentially presents substantially the entire length of the cutting edge178against the abrasive surface.

The rolling contact provided by the rotatable edge guide130reduces the propensity for the associate roller member to dull that portion of the cutting edge that has already been presented against the abrasive surface. It will be noted that the stationary edge guide182can also be configured as a rolling guide as desired.

As further shown byFIG. 7C, the user continues to retract the knife170so that at some point the cutting edge will no longer contactingly engage the stationary edge guide182, but will still be supported by the rotatable edge guide130. The side surface176remains in contacting alignment against the guide surface124B. The knife retraction path174can include an upwardly rotatable component to maintain the presentation angle of the cutting edge178in a desired relation to the abrasive surface, as shown. Multiple successive passes, such as 3-10 passes, may be applied to each side of the knife170, and different belts may be installed to provide successively different rates of material removal, as discussed below.

FIG. 8is an isometric depiction of a rotatable edge guide130A in accordance with further embodiments. The rotatable edge guide130A as depicted inFIG. 8is nominally identical to and includes substantially all of the features discussed above for the rotatable edge guide130, except that the base structure plate132is supplied with a different configuration to facilitate further deflection characteristics for the edge guide.

More particularly, the configuration ofFIG. 8allows the edge guide130A to be moved to an intermediate position (a so called “deflected contact” position) where the edge guide is partially rotated about the central axis146(FIG. 4) but remains in contact with and continues to supply rotational support for the cutting edge of a cutting tool.

As shown in greater detail inFIGS. 9A and 9B, the plate132is provided with opposing cam surfaces186each having an intermediate base portion188and opposing ramps190,192. The base portion188serves as a normal resting location for the rotatable edge guide130A in the deployed position. Rotational deflection of the rotatable edge guide130A due to a downwardly applied force from the cutting edge of a tool causes the respective cam flanges to concurrently travel up the associated ramps (as shown for cam flange154A and ramp190inFIG. 9B). As before, a retention notch194is supplied in the plate132to retain the edge guide130in the retracted position, as generally illustrated inFIG. 8.

FIGS. 10A and 10Bshow a partial sharpening sequence for another exemplary sharpening tool200. The tool200is characterized as a kitchen knife with a handle202, blade portion204, side surface206and cutting edge208. The cutting edge208includes a guard projection210at the base of the blade. It can be seen that the contacting engagement between the guard projection210inFIG. 10Aadvances the rotatable edge guide130A to the deflected contact position, after which the edge guide returns to the normally deployed position shown inFIG. 10B.

As noted above, the translational movement of the rotatable edge guide130,130A disclosed herein allows a wide variety of different types and styles of cutting tools to be sharpened using the tool sharpener100.FIG. 11illustrates a utility tool210with a circuitous blade212that can be sharpened using the rotatable edge guide130in the deployed position.FIG. 12shows a fillet knife210with a finger guard212extending from a handle214. Movement of the rotatable edge guide130to the retracted position provides the necessary clearance to enable a blade216of the knife210to be readily sharpened.

FIGS. 13A and 13Bgenerally illustrate a first deflection mode of the abrasive medium114during sharpening using the tool sharpener100in accordance with some embodiments. An exemplary cutting tool (kitchen knife)230includes a handle232, blade portion234, side surface236and cutting edge238. The abrasive belt114twists out of its normally aligned neutral plane (e.g., out of the normally presented planar extent) in the vicinity of the knife200as the cutting edge238is drawn across the belt. This deflection is represented by torsion arrow240. Generally, the moving belt114will undergo localized torsion (twisting) to maintain a nominally constant angle between the abrasive surface and the cutting edge238, so that greater changes in the curvilinearity of the cutting edge (e.g.,238) will tend to increase the amount of torsional deflection of the belt114.

In this way, a constant and consistent grinding plane can be maintained with respect to the blade material and shape. A first amount of torsion in a generally counter-clockwise direction occurs near the handle232as shown byFIG. 13A, and a second amount of torsion in a generally clockwise direction (torsion arrow242) occurs near the blade tip as shown inFIG. 13B. As noted above, these changes are induced responsive to changes in the curvilinearity of the cutting edge238.

FIGS. 14A and 14Bgenerally illustrate a second deflection mode of abrasive medium114during sharpening using the tool sharpener100in accordance with some embodiments. The sharpener100provides a convex grind surface geometry to a cutting tool (knife)250.FIG. 14Ashows a blade portion252of the knife with side surfaces254,256and cutting edge258. The side surface254is contactingly aligned against the associated guide surface of the stationary guide assembly120to align the side surface254along a selected guide plane260. A portion of the side surface256contactingly engages a first abrasive medium (belt)114-1.

When alternately applied to opposing sides of the blade252, the first abrasive medium114-1provides continuously extending, substantially convex surfaces along sides254,256which converge and intersect to form the cutting edge258. The first abrasive medium114-1is characterized as an endless abrasive belt having a relatively coarse abrasive level, and relatively high linear stiffness characteristics.

FIG. 14Bshows a subsequent grinding operation upon the blade portion252of the knife250a second abrasive medium114-2. The second abrasive medium114-2is also characterized as an endless abrasive belt with a relatively fine abrasive level and a relatively lower linear stiffness. This allows the second belt114-2to induce a smaller radius of curvature as compared to the first belt114-1, providing the blade with a compound convex geometry that provides an extremely sharp final cutting edge258.

It is contemplated in some embodiments that sharpening operations can be carried out as discussed above using a first belt such as114-1to provide a coarse grinding operation, followed by replacement of the first belt with a second belt such as114-2to provide a fine grinding (honing) operation. The rotatable edge guide130and stationary guide assembly120can be used to provide support during these and other types of sharpening operations.

While various embodiments set forth above have provided rotatable edge guide arrangements in the context of an endless abrasive belt, the arrangements can further be adapted for other forms of abrasive media, such as but not limited to rotatable abrasive disks.FIG. 15is an isometric depiction of another tool sharpener300constructed and operated in accordance with various embodiments of the present disclosure.

As explained below, the tool sharpener300is adapted to sharpen a wide variety of different styles and types of cutting tools using a sequence of sharpening stations, each adapted to accommodate a different type of sharpening operation. In some embodiments, the stations can be used to provide multi-stage sharpening as discussed above inFIGS. 14A-14B, but through the use of rotating abrasive disks rather than endless abrasive belts.

In other embodiments, the stations can be used to accommodate sharpening operations on different types of tools requiring different presentation angles, such as kitchen knives and scissors, etc. Regardless, the various operational features discussed above for the tool sharpener100are incorporated and adapted into the tool sharpener300, as will now be explained.

The tool sharpener300includes a base structure302which encloses and/or supports various features of interest, including an electrical motor (not separately shown) to provide motive power during the sharpening operation. A user activated switch304can be used to selectively activate the powered operation of the sharpener.

A number of abrasive members, in this case three (3), are shown at306,308and310. The abrasive members306,308,310are supported within the interior of the base structure302and are respectively characterized as rotatable abrasive disks with abrasive surfaces supplied on opposing sides thereof. It is contemplated that the abrasive surfaces each have respective planar extents that extend along a neutral plane during operation of the sharpener300to accommodate the presentation of the cutting edge of a tool during a sharpening operation. The abrasive surfaces may have a common abrasiveness level, or may be different from one disk to the next.

The abrasive disks can be formed of any suitable material and may be rigid, axially deflectable and/or radially deformable. In some embodiments the disks are flexible (“floppy”) so that, when at rest, the flexible disks rest in a somewhat deformed, bent and/or quasi-folded position due to the force of gravity. Once rotation is initiated, however, the disks quickly transition to the aforementioned neutral plane due to centripedal forces induced by disk rotation. The use of flexible disks may impart similar deformation modes as discussed above inFIGS. 13A-14Band allow the generation of complex concave grind geometries.

As noted above, each disk306,308,310forms a portion of a separate sharpening station312,314and316, with each sharpening station accommodating double sided sharpening. Detailed aspects of the sharpening station312are generally depicted inFIG. 16. It will be appreciated that the other sharpening stations314,316can be provisioned with similar features and therefore separate illustration and discussion of these stations will be omitted for clarity.

As shown inFIG. 16, the sharpening station312includes a sharpening guide assembly320adjacent opposing planar extents306A,306B of disk306. The sharpening guide assembly320includes a pair of opposing, stationary sharpening guides322A,322B. As before, the stationary sharpening guides322A,322B have respective guide surfaces324A,324B which extend along respective guide planes at a common, fixed acute angle with respect to the neutral planes of the planar extents306A,306B. The guide surfaces324A,324B contactingly support the respective side surfaces of a cutting tool during a double-sided sharpening operation as the cutting tool is presented against each guide surface in turn. As desired, stationary edge guides326A,326B can be provided as shown.

As with the guide assembly120discussed above, the guide assembly320can be configured to be adjustable to selectively set the guide surfaces324A,324B to a selected common fixed angle. However, in other embodiments the angle of each station is not adjustable. The angle of each station may vary from one station to the next. For example, station312may be set at nominally 20 degrees, station314may be set at nominally 25 degrees, and station316may be set at nominally 40 degrees. Other respective values can be used as desired.

Referring again toFIG. 15, the tool sharpener300is further provisioned with a rotatable edge guide330to provide cutting edge support during sharpening operations in a manner as generally set forth above. The rotatable edge guide330, however, is configured as a continuous roller member332which spans each of the sharpening stations312,314and316. The roller member332is supported by a central body334and is adapted to rotate about an edge roller axis340.

As before, the roller member332is formed of a compliant material to enhance rolling contact between the roller member332and the cutting tool during a sharpening operation. The rotatable edge guide330is further configured for rotation about an edge guide central axis established by a pivot member342secured to the base structure302. A biasing member (e.g., coiled spring)344supplies a biasing force upon the central body334.

In this way, as shown inFIGS. 17A-17C, the rotatable edge guide330can be transitioned between a deployed position (FIG. 17A), a retracted position (FIG. 17B) and a deflected contact position (17C). As desired, a locking mechanism such as a retention tab member346can be used to retain the edge guide330in the retracted position. The locking mechanism can take any suitable form and need not necessarily engage the roller332; instead, other portions of the edge guide330can be engaged. A detent switch arrangement can be used so that the user pushes the roller member332down a first time to lock the roller member in the retracted position, and then pushes the roller member down a second time to release the roller member and allow the biasing member344to return the roller member to the deployed position.

It will be noted that the edge roller axis340is nominally parallel to the axis of rotation of the disks306,308and310, and is also nominally parallel to the edge guide central axis of pivot342, during all positional modes. The roller member332is a first distance from the respective guide members (e.g.,332A,332B) in the deployed position and a second, greater distance from the respective guide members in the retracted position.

FIGS. 18A and 18Bgenerally illustrate a sharpening sequence upon another exemplary cutting tool350using the tool sharpener300. The cutting tool350is characterized as a kitchen knife and includes handle352, blade portion354, opposing side surfaces (one of which is shown at356), cutting edge358, and guard projection360which extends from the cutting edge358.

In a manner similar to the sharpening operations discussed above, the user inserts the knife350into the appropriate slot and brings a portion of the side surface356into contacting engagement with the associated guide surface (such as guide surface324B inFIG. 16). The cutting edge358is rotatably supported by the roller member332and, as desired, a stationary edge guide (e.g.,326A,326B inFIG. 16) on an opposing side of the disk306.FIG. 18Ashows translation of the roller edge guide330to the deflected contact position to accommodate the guard projection360, andFIG. 18Bshows translation of the roller edge guide330to the deployed position.

It will now be appreciated that the various embodiments presented herein provide a number of benefits over the art. The use of a rotating edge guide advantageously provides mechanical support, via rolling non-dulling contact, the cutting edge during a sharpening operation. The edge guide allows precise location of the cutting tool relative to the abrasive member over repeated sharpening passes. The translational aspects of the edge guide further allow the roller to be fully retracted out of the way as needed, and in some cases, partially deflected to accommodate guard projections and other features that would otherwise tend to interfere with the sharpening process.

While motor-driven powered sharpeners have been disclosed herein, such is merely exemplary and is not limiting. Any number of different types of sharpener configurations can employ the various features exemplified herein, including sharpeners that do not employ a motor-driven abrasive surface.