Knife Blade Profile with Thickness Gradient for Strength

Solution Overview

Problem

Existing knife blades, particularly those with hollow ground profiles, face issues of weakness and increased maintenance due to thin sections, which can lead to collapse and require frequent resharpening, affecting performance and longevity.

Innovation Solution

A knife blade profile with a specific thickness gradient starting from a shoulder, transitioning to thicker sections along the blade, ensuring strength and flexibility, with preferred thickness measurements at various points to minimize the risk of collapse and maintain cutting performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the blade is hollow ground to reduce thickness near the cutting edge, then the cutting performance is improved, but the blade creates weak sections that can collapse under normal use

Engineering Contradiction:

Improvecutting performanceVSAvoidblade strength

Core Design Contradiction:

Ease of operationVSStrength

Solution Approach 1:

The blade profile applies local quality by having different thickness characteristics in different zones: a relatively thinner section at the cutting edge for cutting performance, transitioning to a thicker section toward the back for strength. This is achieved through a specific convex curvature profile that controls the thickness distribution along the blade length, ensuring each zone has the appropriate thickness for its function.

Inventive Principle:

Principle #3Local quality

2Reliability

If the cutting edge is ground to a wider angle for stainless steel, then the blade durability is improved, but the blade thickness increases which increases the work required to move the knife through material

Engineering Contradiction:

Improveblade durabilityVSAvoidwork required to move knife

Core Design Contradiction:

ReliabilityVSForce

Solution Approach 1:

The blade profile applies local quality by having different thickness characteristics in different zones: a relatively thinner section at the cutting edge for cutting performance, transitioning to a thicker section toward the back for strength. This is achieved through a specific convex curvature profile that controls the thickness distribution along the blade length, ensuring each zone has the appropriate thickness for its function.

Inventive Principle:

Principle #3Local quality

3Force

If the hollow ground section runs parallel to the peripheral edge, then the blade thickness is reduced to minimize cutting force, but a thin weak section is created above the shoulder

Engineering Contradiction:

Improvecutting forceVSAvoidblade strength

Core Design Contradiction:

ForceVSStrength

Solution Approach 1:

The blade profile uses curvature by implementing a convex curvature along the blade length rather than a straight hollow ground section. This convex profile creates a smooth, continuous thickness transition from the cutting edge to the back, eliminating the abrupt thin section above the shoulder that characterizes traditional hollow ground blades. The curved profile ensures gradual thickening that maintains strength while preserving cutting efficiency.

Inventive Principle:

Principle #14Spheroidality (Curvature)

Data Source

PatentUS9956696B2Knife

Publication Date: 2018.05.01 D M DUNNINGHAM LTD

AI summary

A knife blade with a back, and a cutting edge with a shoulder, characterised in that the knife blade has a blade profile perpendicular to the blade edge that, starting at the shoulder and moving towards the back, has the following thickness, as ground prior to any polishing or subsequent steps, at the position indicated: at the shoulder a thickness of AA; at about 1/16″ from the shoulder a thickness of BB; and at about ⅛″ from the shoulder a thickness of CC; where AA is about 16 to 23 thousandths of an inch (0.41 mm to 0.58 mm); BB is AA plus about 3 thousandths of an inch (0.076 mm); and CC is BB plus about 2 thousandths of an inch. (0.051 mm).