Rotary Cutting Tool Chip Breaker Geometry for Rigidity and Chip Discharge

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Rotary cutting tools face challenges with increased cutting resistance and reduced processing precision when processing multiple stacked material boards or higher feed rates, leading to potential tool breakage and chip accumulation, which existing chip breaker groove configurations fail to adequately address.

Innovation Solution

A rotary cutting tool design featuring a chip breaker groove with a shallower depth at the base end than at the tip end, combined with a helical chip discharge groove and optimized cutting edge geometry, to enhance tool rigidity and reduce cutting resistance while maintaining effective chip discharge performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-generated harmful factors

If the chip breaker groove depth is increased to improve chip discharge performance, then chip discharge performance is improved, but tool body rigidity decreases leading to increased breakage risk

Engineering Contradiction:
Improvechip discharge performanceVSAvoidtool body rigidity
Core Design Contradiction:
Object-generated harmful factorsVSStrength

Solution Approach 1:

The chip breaker groove depth is made non-uniform along the tool body length, with shallower depth at the base end and deeper depth at the tip end. This local variation allows the base end to maintain rigidity while the tip end provides effective chip discharge, resolving the contradiction between chip discharge performance and tool body rigidity.

Inventive Principle:
Principle #3Local quality

2Strength

If the chip breaker groove depth is decreased to improve tool body rigidity, then tool body rigidity is improved, but chip discharge performance deteriorates

Engineering Contradiction:
Improvetool body rigidityVSAvoidchip discharge performance
Core Design Contradiction:
StrengthVSObject-generated harmful factors

Solution Approach 1:

By making the chip breaker groove depth vary along the tool body length, the invention ensures that the base end maintains sufficient rigidity while the tip end provides adequate chip discharge capability, thus resolving the contradiction between rigidity and chip discharge performance.

Inventive Principle:
Principle #3Local quality

3Strength

If the pitch of chip breaker groove is increased to improve tool body rigidity, then tool body rigidity is improved, but outer peripheral cutting edge length increases leading to increased cutting resistance

Engineering Contradiction:
Improvetool body rigidityVSAvoidcutting resistance
Core Design Contradiction:
StrengthVSForce

Solution Approach 1:

The invention uses non-uniform chip breaker groove depth rather than varying pitch, which avoids increasing the outer peripheral cutting edge length while still improving tool body rigidity at the base end, thus resolving the contradiction between rigidity and cutting resistance.

Inventive Principle:
Principle #3Local quality

4Productivity

If processing is performed with increased number of stacked material boards or higher feed rate to improve productivity, then productivity is improved, but cutting resistance increases leading to tool breakage and precision deterioration

Engineering Contradiction:
Improveprocessing efficiencyVSAvoidcutting resistance
Core Design Contradiction:
ProductivityVSForce

Solution Approach 1:

The invention changes the geometric parameters of the chip breaker groove (non-uniform depth distribution) to optimize the balance between chip discharge and tool rigidity, enabling the tool to withstand higher cutting resistance generated during high-productivity processing of multiple stacked material boards.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP3858525B1Rotary cutting tool
Publication Date: 2024.12.04 UNION TOOL CO
  • EP3858525B1 patent drawingFigure 1
  • EP3858525B1 patent drawingFigure 2
  • EP3858525B1 patent drawingFigure 3

AI summary

An object of the present invention is to provide a rotary cutting tool that excels in breakage resistance and chip discharge performance, and also enables high processing precision with minimal cutting resistance. The present invention is a rotary cutting tool in which: a chip discharge groove (2) assuming a helical shape from a tip end to a base end side of a tool body (1) is formed in an outer periphery of the tool body (1), an outer peripheral cutting edge (3) is formed in an intersecting ridgeline part between a rake face of the chip discharge groove (2) and an outer circumferential surface of the tool body (1) or an outer peripheral flank face formed in the outer periphery of the tool body (1), and a chip breaker groove (4) is provided so as to partition the outer peripheral cutting edge (3), wherein a depth of the chip breaker groove (4) at a groove base end part of the chip breaker groove (4) is shallower than a depth at a groove tip end part.