Cutting Insert Recesses Prevent Chip Sliding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing cutting inserts face issues with spiral chips sliding off the flank, leading to damage during machining, particularly due to the narrow gap between the insert and the tool or workpiece, which is not effectively addressed by existing designs that focus on varying clearance angles and shallow recesses.

Innovation Solution

A cutting insert design featuring recesses that extend at least 60% of the cutting edge's length, with a distance from the cutting edge of at least one-tenth to a quarter of the insert's thickness, and an abrupt angle of 60° to 90°, allowing chips to get stuck in the recesses rather than sliding off, thereby reducing the risk of damage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If shallow recesses or raised projections are provided on the clearance surface extending close to the cutting edge to create varying clearance angles, then cutting performance is improved, but helical chips still slide off the clearance face and get caught in the narrow gap between insert and tool seat

Engineering Contradiction:
Improvecutting performanceVSAvoidchip sliding off and causing damage
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The clearance surface is segmented into multiple zones: a first zone with varying clearance angles (using shallow recesses/projections near the cutting edge) for improved cutting performance, and a second zone with a deep groove structure further from the cutting edge for chip containment. This segmentation allows each zone to perform its specific function independently.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The deep groove acts as an intermediary structure between the varying clearance angle zone and the chip discharge path. It intercepts helical chips before they can slide off the clearance face into the narrow gap, serving as a protective mediator that prevents damage while allowing the varying clearance angles to maintain cutting performance.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of operation

If the clearance surface is kept flat and smooth to reduce friction, then chip flow is improved, but helical chips cannot be effectively contained and tend to slide off causing damage

Engineering Contradiction:
Improvechip flowVSAvoidchip sliding off and causing damage
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The clearance surface exhibits different local qualities at different positions: near the cutting edge, the surface has varying clearance angles with shallow recesses/projections for optimal chip formation and flow; further from the cutting edge, a deep groove is introduced to provide chip containment. This local differentiation allows the surface to simultaneously promote chip flow and prevent chip sliding off.

Inventive Principle:
Principle #3Local quality

3Reliability

If recesses are provided close to the cutting edge to vary clearance angles, then cutting performance improves, but the structural integrity near the cutting edge may be compromised

Engineering Contradiction:
Improvecutting performanceVSAvoidstructural integrity near cutting edge
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The recess structure is segmented into two functional parts: shallow recesses/projections located close to the cutting edge for varying clearance angles and improving cutting performance, and a deep groove located further from the cutting edge for chip containment. The shallow nature of the recesses near the cutting edge minimizes impact on structural integrity while the deep groove is positioned where it provides maximum chip containment with minimal structural compromise.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP2654993B1Cutting insert with structured side surfaces
Publication Date: 2019.02.20 WALTER AG
  • EP2654993B1 patent drawingFigure 1~2
  • EP2654993B1 patent drawingFigure 3
  • EP2654993B1 patent drawingFigure 4

AI summary

The invention relates to a cutting insert having an upper and a lower surface (1, 2), and having one or more edge surfaces (3) connecting the upper (1) and the lower surfaces (2) to each other, wherein at least one cutting edge (4) is implemented at the transition of at least one edge surface (3) to at least the upper area (1), wherein the upper surface adjacent to the cutting edge is designed as a chip surface and the edge surface adjacent to the cutting edge is implemented as a tool flank (3). In order to provide a cutting insert in which the chip breaking area is expanded and the risk of damage to the cutting insert and/or the tool and/or the workpiece due to coiling chips is reduced, according to the invention, at least one recess (6) is provided in the tool flank (3) at a distance from the cutting edge (4).