Curved Parting Insert Edge for Cleaner Metal Cutoff

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing cutting inserts for parting off metal work pieces often result in burr formation due to bending caused by transverse forces, making it difficult to achieve a clean cut.

Innovation Solution

A cutting insert design with a cutting edge featuring a rearmost point between the leading and trailing cutting corners, which reduces off-axis forces and enhances the leading cutting corner's prominence, thereby minimizing burr formation and improving cut cleanliness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If a straight cutting edge is used with leading and trailing cutting corners, then the cutting insert can separate the work piece from the rod, but transverse forces cause bending of the cutting insert which increases burr formation

Engineering Contradiction:
Improvecut cleanlinessVSAvoidcutting insert bending
Core Design Contradiction:
Manufacturing precisionVSStability of the object's composition

Solution Approach 1:

The cutting edge is designed with a curved profile instead of a straight line, featuring a rearmost point that is axially rearward from both the leading and trailing cutting corners. This curvature redistributes the cutting forces along the cutting edge path, reducing the transverse force component that causes bending of the cutting insert, thereby minimizing burr formation while maintaining effective material separation.

Inventive Principle:
Principle #14Spheroidality (Curvature)

2Manufacturing precision

If the cutting edge is tilted with respect to the axis of rotation, then slug formation is reduced, but the transverse forces still cause bending and affect cut quality

Engineering Contradiction:
Improveburr formationVSAvoidoff-axis forces
Core Design Contradiction:
Manufacturing precisionVSForce

Solution Approach 1:

The curved cutting edge profile with the rearmost point positioned axially rearward creates a more favorable force distribution during the cutting process. This curvature allows the cutting edge to engage and disengage from the work piece in a controlled manner, reducing the magnitude of off-axis forces while maintaining the tilted configuration needed to minimize slug formation.

Inventive Principle:
Principle #14Spheroidality (Curvature)

3Loss of substance

If the cutting insert has a small width to reduce material waste, then less material is wasted in the cut, but the cutting insert becomes more susceptible to bending from transverse forces

Engineering Contradiction:
Improvematerial wasteVSAvoidresistance to bending
Core Design Contradiction:
Loss of substanceVSStrength

Solution Approach 1:

The curved cutting edge design compensates for the reduced structural stiffness of narrow cutting inserts by optimizing the force application path. The rearmost point configuration ensures that cutting forces are distributed more evenly along the cutting edge, reducing peak transverse loads that would otherwise cause bending in narrow inserts, thus enabling clean cuts with minimal material waste.

Inventive Principle:
Principle #14Spheroidality (Curvature)

Data Source

PatentEP3785830A1Cutting insert for parting off a metal work piece
Publication Date: 2021.03.03 WALTER AG
  • EP3785830A1 patent drawingFigure 1~2
  • EP3785830A1 patent drawingFigure 3~4
  • EP3785830A1 patent drawingFigure 5~6

AI summary

The present invention relates to a cutting insert (1) for parting off a metal work piece, the cutting insert (1) comprising an elongated body (18), which elongated body (18) has a top surface (4), a bottom surface (5), a first lateral surface (8) and a second lateral surface (9) connecting the top surface (4) and the bottom surface (5) at one lateral side each, a front surface (12) connecting the first and second lateral surfaces (8, 9), the top surface (4) and the bottom surface (5), a longitudinal axis (10) extending axially rearward from the front surface (12) in a central plane, and a cutting head (2) comprising a cutting edge (11), which cutting edge (11) is formed at an intersection between the front surface (12) and the top surface (4), and which cutting edge (11) includes a leading cutting corner (13) at the first lateral side surface (8), and a trailing cutting corner (14) at the second lateral side surface (9), wherein the trailing cutting corner (14) is located axially rearward of the leading cutting corner (13), such that the cutting edge (11) has a rearmost point (16), which rearmost point (16) is located axially rearward from the trailing cutting corner (14).