Hand-held sharpener with multi-stage sharpening capabilities

Patent metadata

Field	Value
Publication number	US-9833879-B1
Application number	US-201514715822-A
Country	US
Kind code	B1
Filing date	May 19, 2015
Priority date	Dec 8, 2010
Publication date	Dec 5, 2017
Grant date	Dec 5, 2017

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.

First claim

What is claimed is:

1. A sharpener for sharpening a cutting tool having a blade portion with opposing first and second side surfaces and a cutting edge therebetween, the sharpener comprising:
a handle having a longitudinal axis and an outer grip surface which surrounds said longitudinal axis, the outer grip surface adapted to be grasped by the hand of a user;
a first sharpening stage incorporated into the handle and comprising a first abrasive surface and a first stage guide surface having a line contact portion that linearly extends at a first angle with respect to the first abrasive surface, the first sharpening stage adapted to facilitate a primary sharpening operation by a user upon the tool responsive to the user contactingly engaging the first side of the blade against the first stage guide surface and contactingly advancing the cutting edge of the blade portion against the first abrasive surface to define a first beveled portion on the second side surface; and
a second sharpening stage comprising an elongated member which extends from the handle in a direction parallel to the longitudinal axis, the second sharpening stage further comprising a second stage guide surface having a line contact portion that linearly extends in a non-orthogonal direction with respect to a second abrasive surface on the elongated member at a single second angle, the second sharpening stage adapted to facilitate a secondary sharpening operation by the user upon the tool responsive to the user contactingly engaging the first side surface of the tool with the second stage guide surface to orient the tool at said second angle, and advancing the cutting edge of the tool against the second abrasive surface while maintaining the tool at the second angle to define a second beveled portion of the first side surface between the first beveled portion and the cutting edge.

2. The sharpener of claim 1 , wherein the elongated member is characterized as an abrasive rod having a proximal end adapted for insertion into a corresponding recess in the handle to attach the second sharpening stage to the handle, and wherein the second stage guide surface is affixed to the elongated member adjacent the proximal end and extends toward an opposing distal end of the elongated member.

3. The sharpener of claim 2 , wherein the abrasive rod is nominally cylindrically shaped.

4. The sharpener of claim 2 , wherein the abrasive rod is nominally frusto-conically shaped.

5. The sharpener of claim 2 , wherein the abrasive rod is nominally rectilinearly shaped.

6. The sharpener of claim 1 , wherein the first sharpening stage comprises first and second crossed metal sharpening blades.

7. The sharpener of claim 1 , wherein the second angle is greater than the first angle.

8. The sharpener of claim 1 , wherein the second stage guide surface is a first guide surface on a first side of the elongated member, and the second sharpening stage further comprises a second guide surface attached to a second side of the elongated member and which has a line contact portion that linearly extends in a non-orthogonal direction with respect to the second abrasive surface on the elongated member at a single third angle.

9. The sharpener of claim 8 , wherein the second and third angles are equal.

10. The sharpener of claim 8 , wherein the second and third angles are not equal and both are greater than the first angle.

11. The sharpener of claim 1 , wherein the first guide surface comprises a line contact that linearly extends toward the first abrasive surface so that the first angle extends from the first guide surface to the first abrasive surface.

12. The sharpener of claim 1 , wherein the second angle is nominally 25 degrees or less.

13. A sharpener for sharpening a cutting tool having a blade portion with opposing first and second sides and a cutting edge therebetween, the sharpener comprising:
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 in the handle between the first and second ends, the primary sharpening stage comprising a first abrasive surface extending at a first angle with respect to a first guide surface to facilitate a primary sharpening operation by a user upon the tool; and
an abrasive rod extending from the first end of the handle in a direction parallel to the longitudinal axis, the handle comprising a second guide surface having a line contact portion that linearly extends from the first end toward the abrasive rod to provide a single second angle from the second guide surface to a second abrasive surface of the abrasive rod, the abrasive rod and the second guide surface forming a second sharpening stage adapted to facilitate a secondary sharpening operation by the user upon the tool.

14. The sharpener of claim 13 , wherein the primary sharpening stage is characterized as a pull through ripper comprising a pair of crossed blade members.

15. The sharpener of claim 13 , wherein the abrasive rod is substantially rectilinear in cross-sectional shape.

16. The sharpener of claim 13 , wherein the handle further comprises a flat support surface configured to be contactingly placed on a base surface during a sharpening operation, and a recessed surface to provide clearance between the handle and the base surface.

17. The sharpener of claim 13 , wherein the abrasive rod tapers at a distal end thereof opposite the handle.

18. The sharpener of claim 13 , wherein the second guide surface is on a first side surface of the handle, and the handle further comprises a third guide surface on a second side surface of the handle, the third guide surface having a line contact portion that linearly extends from the first end toward the abrasive rod to provide a single third angle from the third guide surface to the abrasive rod.

19. The sharpener of claim 18 , wherein the second and third angles are equal to or greater than the first angle.

20. The sharpener of claim 18 , wherein the second and third second angles are not equal and both are greater than the first angle.

21. The sharpener of claim 13 , wherein the handle further comprises an aperture extending through the second end of the handle.

22. The sharpener of claim 13 , wherein the second angle is nominally 25 degrees or less.

Assignees

• Darex Llc

Inventors

• Dovel Daniel T

Classifications

• B24D15/08 Primary

  of knives; of razors · CPC title

• B24D15/065

  for sharpening both knives and scissors · CPC title

• B24B3/54

  of hand or table knives · CPC title