Powered sharpener with controlled deflection of flexible abrasive member

Patent metadata

Field	Value
Publication number	US-10814451-B2
Application number	US-201815919850-A
Country	US
Kind code	B2
Filing date	Mar 13, 2018
Priority date	Feb 12, 2016
Publication date	Oct 27, 2020
Grant date	Oct 27, 2020

Abstract

Apparatus and method 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 moves a flexible abrasive member such as a belt or disc along a neutral plane. A support member contactingly supports a back side of the flexible abrasive member at a medial location along the neutral plane. The support member is positioned adjacent a contact region of an abrasive surface on an opposing front side of the flexible abrasive member against which a cutting edge is brought during a sharpening operation. In some cases, the support member is a stationary or moveable support member such as a pin or roller offset from the contact region. In other cases, the support member is a platen that projects forward to support the contact region.

First claim

What is claimed is:

1. A sharpener for sharpening a cutting tool, comprising:
a flexible abrasive member that is moved by an electric motor and supported by at least a first support member along a neutral plane having opposing proximal and distal ends, the flexible abrasive member having a front side with an abrasive surface and a back side opposite the front side;
a second support member disposed to contactingly engage the back side of the flexible abrasive member between the proximal and distal ends so that the neutral plane comprises a first segment that extends from the proximal end toward the second support member and a second segment that extends from the second support member toward the distal end; and
a guide assembly adjacent the flexible abrasive member to support the cutting tool during a sharpening operation in which a cutting edge of the cutting tool is presented against the flexible abrasive member, the guide assembly having a side support surface to contactingly support a side surface of the cutting tool and an edge guide surface to concurrently contactingly support a first portion of the cutting edge of the cutting tool while a second portion of the cutting edge of the cutting tool is presented against a contact region of the abrasive surface to deflect the flexible member out of the neutral plane, the contact region offset from the second support member and disposed along a selected one of the first or second segments, the second support member imparting a non-uniform surface pressure of the abrasive surface against the second portion of the cutting edge.

2. The sharpener of claim 1 , wherein the second support member is a stationary support member across which the flexible abrasive member contactingly passes.

3. The sharpener of claim 1 , wherein the second support member is a roller member having a circumferentially extending outer surface that rotates about a roller axis during contacting passage of the flexible abrasive member.

4. The sharpener of claim 1 , wherein the first support member is a rotatable roller that rotates about a roller axis and which supports a first end of the neutral plane of the flexible abrasive member.

5. The sharpener of claim 4 , wherein the flexible abrasive member is an abrasive belt, the rotatable roller is a first belt support roller, and the sharpener further comprises a second belt support roller that supports an opposing second end of the neutral plane.

6. The sharpener of claim 4 , wherein the flexible abrasive member is an abrasive disc that rotates about the roller axis.

7. The sharpener of claim 1 , wherein the guide assembly forms a substantially u-shaped channel.

8. The sharpener of claim 1 , wherein the guide assembly forms a substantially v-shaped channel.

9. The sharpener of claim 1 , wherein the second support member is offset from the contact region such that the back side of the abrasive flexible member is unsupported opposite the contact region and the abrasive flexible member is directed to follow a localized serpentine path by the contact supplied by the second portion of the cutting edge in the contact region and the second support member.

10. The sharpener of claim 1 , wherein the first support member establishes a first tangential plane for the flexible abrasive member and a distal end of the second support member protrudes beyond this first tangential plane to place the flexible abrasive member into the neutral plane.

11. The sharpener of claim 1 , wherein the second support member supplies the non-uniform surface pressure along the second portion of the cutting edge so that a greater surface pressure is supplied at a distance closer to the second support member and a reduced surface pressure is supplied at a distance farther from the second support member.

12. A sharpener for sharpening a cutting tool, comprising:
a flexible abrasive member that is moved by an electric motor and supported by at least a first support member along a neutral plane having opposing proximal and distal ends, the flexible abrasive member having a front side with an abrasive surface and a back side opposite the front side;
a guide assembly adjacent the flexible abrasive member to support the cutting tool during a sharpening operation in which a cutting edge of the cutting tool is presented against the flexible abrasive member, the guide assembly having a side support surface to contactingly support a side surface of the cutting tool and an edge guide surface to concurrently contactingly support a first portion of the cutting edge of the cutting tool while a second portion of the cutting edge of the cutting tool is presented against a contact region of the abrasive surface; and
a platen member disposed to contactingly support the back side of the flexible abrasive member between the proximal and distal ends of the neutral plane opposite the contact region, the platen member applying a biasing force to displace the flexible abrasive member toward the contact region beyond an initial tangential plane established by the first support member.

13. The sharpener of claim 12 , further comprising a biasing member attached to the platen member to advance the medial portion of the flexible abrasive member toward the contact region away from the tangential plane to the neutral plane.

14. The sharpener of claim 13 , wherein the biasing member comprises a spring that urges the medial portion of the flexible abrasive member toward the contact region away from the tangential plane to the neutral plane.

15. The sharpener of claim 12 , wherein the first support member is a first roller, the flexible abrasive member is an abrasive belt routed along the first roller and a spaced apart second roller, wherein the first and second rollers are arranged to form the initial tangential plane for the flexible abrasive member, and wherein the platen member is disposed between the first and second rollers to advance the medial portion of the belt out of the initial tangential plane toward the contact region to form the neutral plane.

16. The sharpener of claim 12 , wherein the flexible abrasive member is an abrasive disc that rotates about an axis of the first support member.

17. The sharpener of claim 12 , wherein the guide assembly forms a substantially u-shaped channel.

18. The sharpener of claim 12 , wherein the guide assembly forms a substantially v-shaped channel.

19. The sharpener of claim 12 , wherein the flexible abrasive member moves in a first direction across the contact region against which the second portion of the cutting edge is presented thereagainst, and wherein the platen imparts a curvilinear shape to the medial portion of the neutral plane to effect a hollow grind geometry to a side of the cutting tool.

20. The sharpener of claim 12 , wherein the flexible abrasive member comprises an endless abrasive belt routed along at least first, second and third rollers arranged in a generally triangular pattern to form a first planar extend between the first and second rollers and a second planar extent between the first and third rollers, the first and second planar extends at nominally a common angle from a vertical centerline, wherein the platen member is a first platen member which contactingly engages a backing portion of the endless abrasive belt between the first and second rollers to advance the endless abrasive belt to a first neutral plane, and wherein the sharpener further comprises a corresponding second platen member which contacting engages the backing portion of the endless abrasive bel

Assignees

• Darex Llc

Inventors

• Dovel Daniel T

Classifications

• B24B3/54 Primary

  of hand or table knives · CPC title

• B24B23/06

  with abrasive belts, e.g. with endless travelling belts; Accessories therefor · CPC title