Segmented Milling Cutter for Low-Force Composite Machining

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Milling tools used for processing fiber composite materials face high machining forces due to continuous cutting edges, leading to delamination and suboptimal surface quality.

Innovation Solution

A milling tool with a cylindrical shape featuring discrete cutting elements and spiral grooves pointing in both directions, where cutting edges are formed with alternating pressing and pulling cuts, reducing machining forces and preventing delamination by distributing cutting forces effectively.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If continuous cutting edges are used in compression milling cutters, then delamination of the workpiece is counteracted, but machining forces become high

Engineering Contradiction:
Improveprevention of delaminationVSAvoidmachining forces
Core Design Contradiction:
ReliabilityVSForce

Solution Approach 1:

The continuous cutting edges are segmented into discrete cutting elements arranged in multiple rows. This segmentation reduces the total number of cutting edges engaged simultaneously, thereby reducing machining forces while maintaining the delamination prevention effect through the interaction of pushing and pulling cutting edges across different rows

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different rows of cutting elements are assigned different functions: some rows have cutting edges configured for pushing cuts while others are configured for pulling cuts. This local differentiation allows the tool to simultaneously prevent delamination (through the pushing action) and reduce machining forces (through the pulling action that reduces overall cutting resistance)

Inventive Principle:
Principle #3Local quality

2Force

If individual pointed teeth are used instead of continuous teeth, then machining forces are reduced, but cutting action becomes choppy

Engineering Contradiction:
Improvemachining forcesVSAvoidsmoothness of cutting action
Core Design Contradiction:
ForceVSEase of operation

Solution Approach 1:

Multiple rows of discrete cutting elements are combined on the same tool body, with each row contributing to the cutting action. This merging of multiple cutting elements in different rows provides overlapping cutting zones that smooth out the choppy action of individual teeth while maintaining the force-reducing benefits of discrete elements

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The discrete cutting elements are arranged and configured to create a periodic cutting pattern where pushing and pulling cuts alternate in a regular sequence. This periodic action transforms the irregular choppy cutting of single pointed teeth into a rhythmically smooth cutting process with reduced vibration and improved surface quality

Inventive Principle:
Principle #19Periodic action

Data Source

PatentEP3530389B1Milling tool
Publication Date: 2022.08.03 GUNTHER WIRTH HARTMETALLWERKZEUGE
  • EP3530389B1 patent drawingFigure 1a~1b
  • EP3530389B1 patent drawingFigure 1c~2
  • EP3530389B1 patent drawingFigure 3a~3c

AI summary

Milling tool (1) with a substantially straight circular cylindrical basic shape with a longitudinal axis (L) which defines an axial direction along which longitudinal axis (L) at least one cutting section (2) and a shank section (3) as well as an end region (4) are formed, wherein the milling tool (1) has right-pointing spiral flutes (5) and left-pointing spiral flutes (6), and wherein discrete cutting elements (7) are formed between the intersecting spiral flutes (5, 6), on which cutting elements (7) one or more cutting edges (8) are formed, wherein the cutting section (2) has at least: - a first axial cutting region (9) which adjoins the shank section (3), wherein on the discrete cutting elements (7) in the first axial cutting region (9) predominantly cutting edges (8, 82) with a pressing cut are formed - when the milling tool (1) is used in an intended direction of rotation (R),- furthermore, a second axial cutting area (10) adjacent to the face area (4) in which the discrete cutting elements (7) predominantly have cutting edges (8, 81) with a shearing cut when the milling tool (1) is used in a designated direction of rotation (R), - furthermore, a transition area (11) formed with respect to the axial direction between the first (9) and the second (10) cutting area, in which transition area (11) both cutting edges (8, 81) with a predominantly shearing cut and cutting edges (8, 82) with a predominantly pushing cut are formed.