Foldable tool sharpener

Patent metadata

Field	Value
Publication number	US-11267103-B2
Application number	US-202016887857-A
Country	US
Kind code	B2
Filing date	May 29, 2020
Priority date	May 29, 2019
Publication date	Mar 8, 2022
Grant date	Mar 8, 2022

Abstract

Apparatus and method for sharpening a cutting tool, such as a knife. A sharpener includes a first support member, a second support member and a hinge assembly. The first support member supports a first abrasive surface and has at least a first guide at a selected end of the first abrasive surface. The second support member supports a second abrasive surface and has at least a second guide at a selected end of the second abrasive surface. A hinge assembly couples the first and second support member to facilitate movement of the second support member relative to the first support member between a closed position and an open position. In the closed position, the first guide is in facing relation to the second guide and the first abrasive surface is in facing relation to the second abrasive surface.

First claim

What is claimed is:

1. A sharpener for sharpening a cutting tool having a blade portion with a cutting edge, the sharpener comprising:
a first support member which supports a first abrasive surface, the first support member comprising at least a first guide at a selected end of the first abrasive surface, the first abrasive surface comprising an outer surface of a rotatable abrasive rod;
a second support member which supports a second abrasive surface, the second support member comprising at least a second guide at a selected end of the second abrasive surface;
a hinge assembly which couples the first and second support member to facilitate movement of the second support member relative to the first support member between a closed position and an open position, wherein in the closed position the first guide is in facing relation to the second guide and the first abrasive surface is in facing relation to the second abrasive surface; and
a key alignment member affixed to a distal end of the rotatable abrasive rod, the key alignment member comprising a slot adapted to be rotated by insertion of a spine of a blade of the cutting tool therein by a user and rotation of said blade.

2. The sharpener of claim 1 , wherein in the closed position the second abrasive surface is nominally parallel to the first abrasive surface.

3. The sharpener of claim 1 , wherein in the closed position the second support member is nominally parallel to the first support member.

4. The sharpener of claim 1 , wherein the first guide is a forward guide that extends at a first selected angle with respect to the first abrasive surface, wherein the second guide is a reverse guide that extends at a second selected angle with respect to the second abrasive surface.

5. The sharpener of claim 1 , wherein the first and second guides are each characterized as forward guides.

6. The sharpener of claim 5 , wherein the first and second guides are further characterized as spaced-apart, offset fingers that interlock when the sharpener is transitioned to the closed position.

7. The sharpener of claim 1 , wherein the rotatable abrasive rod is characterized as a ceramic rod.

8. The sharpener of claim 1 , wherein the second abrasive surface is an outer surface of a leather strop.

9. The sharpener of claim 1 , wherein the first and second guides each extend at a guide angle with respect to the associated abrasive surface of from about 20 to 25 degrees.

10. The sharpener of claim 1 , wherein the hinge assembly has a limit feature that limits a maximum rotation of the second support member relative to the first support member to nominally 220 degrees so that an intervening angle of nominally 140 degrees exists between the first and second support members to facilitate use, by a user, of a selected one of the first or second support members as a handle while carrying out a sharpening operation upon a cutting tool using a remaining one of the first or second support members.

11. The sharpener of claim 1 , wherein the hinge assembly has a limit feature that limits a maximum rotation of the second support member relative to the first support member so that an intervening angle of from about 110 degrees to about 160 degrees exists between the first and second support members to facilitate use, by a user, of a selected one of the first or second support members as a handle while carrying out a sharpening operation upon a cutting tool using a remaining one of the first or second support members.

12. The sharpener of claim 1 , wherein the first and second guides are in contacting engagement in the closed position.

13. The sharpener of claim 1 , wherein the first and second abrasive surfaces are provided on corresponding first and second abrasive members each having at least a selected one of a round, cylindrical, triangular, frusto-conical, grooved or flat shape.

14. The sharpener of claim 13 , wherein each of the first and second abrasive members is formed of at least a selected one of ceramic, metal, leather, stone, sandpaper, an abrasive block, or a diamond coated member.

15. The sharpener of claim 13 , further comprising a third abrasive member affixed to an outer surface of the first support member opposite the first abrasive member and a fourth abrasive member affixed to an outer surface of the second support member opposite the second abrasive member.

16. The sharpener of claim 1 , wherein the hinge assembly rotates about a hinge axis, wherein the closed position provides the first abrasive surface of the first support member in facing relation and parallel to the second abrasive surface of the second support member so that both the first and second abrasive surfaces intersect a plane normal to the hinge axis, and wherein the open position provides the first abrasive surface of the first support member at a maximum intervening angle determined by a limit feature that prevents further rotation of the second support member with respect to the first support member.

17. A method for sharpening a cutting tool having a blade portion with a cutting edge, the method comprising:
transitioning a foldable sharpener from a closed position to an open position by rotating a second support member relative to a first support member via an intervening hinge assembly that rotates about a hinge axis, the closed position providing a first abrasive surface of the first support member in facing relation and parallel to a second abrasive surface of the second support member so that both the first and second abrasive surfaces intersect a plane normal to the hinge axis, the closed position further providing a first guide surface of the first support member in facing relation to a second guide surface of the second support member, the open position providing the first abrasive surface of the first support member at a maximum intervening angle determined by a limit feature surface of the first support member that prevents further rotation of the second support member with respect to the first support member by way of contact with a shoulder surface of the second support member against the limit surface of the first support member;
performing a primary sharpening operation upon the cutting tool by grasping the second support member in a first hand of a user, grasping the cutting tool in a second hand of the user, and advancing the cutting edge along the first abrasive surface of the first support member; and
performing a secondary sharpening operation upon the cutting tool by subsequently grasping the first support member in the first hand, grasping the cutting tool in the second hand, and advancing the cutting edge along the second abrasive surface of the second support member.

18. The method of claim 17 , wherein the intervening angle between the first and second support members is from about 110 degrees to about 160 degrees when the limit surface of the first support member contactingly engages the shoulder surface of the second support member.

19. The method of claim 17 , further comprising inserting a back portion of a blade of the cutting tool into a slot disposed at an end of a selected one of the first or second support members to rotate a corresponding abrasive member.

20. A sharpener for sharpening a cutting tool having a blade portion with a cutting edge, the sharpener comprising:
a first support member which supports a first abrasive surface, the first support member comprising at least a first guide at a selected end of the first abrasive surface and a limit surface;
a second support member whi

Assignees

• Darex Llc

Inventors

• Baker Steven Lee
• Zachariasen Joseph Todd

Classifications

• B24D15/082 Primary

  the elements being rotatable · CPC title

• B24D15/088

  with whetting leather · CPC title