Roughing End Mill Waveform Layout to Prevent Corner Fracture
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing roughing end mills with waveform patterns on their cutting edges tend to form sharp corners during machining, leading to fracturing and damage to the machined surface, which hinders efficient machining and surface accuracy.
Innovation Solution
The design features a roughing end mill with chip discharge flutes having peripheral cutting edges, end cutting edges, and corner cutting edges with a convex curved shape, where the phase of recesses and protrusions is shifted between flutes, and the foremost protrusion is aligned with the corner cutting edge, preventing sharp corner formation and ensuring efficient machining without fracturing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a corrugated peripheral cutting edge and corner cutting edge are formed with waveform patterns, then roughing capability is improved, but sharp corner portions are formed causing fracturing
Solution Approach 1:
The corner cutting edge is designed with a convex curved line shape instead of sharp corners, and straight portions are introduced to connect the foremost protrusion with the corner cutting edge peak, eliminating sharp corner portions that cause fracturing while maintaining the waveform roughing pattern
2Productivity
If waveform pattern is formed on peripheral cutting edge, then material removal efficiency is improved, but machined surface accuracy deteriorates due to corner portion damage
Solution Approach 1:
The corner cutting edge uses a convex curved line shape and straight connecting portions to eliminate sharp corners, preventing damage to the machined surface during finish machining while preserving the waveform pattern's material removal efficiency
3Ease of manufacture
If all peripheral cutting edges have same phase waveform, then manufacturing simplicity is maintained, but corner portion fracturing occurs
Solution Approach 1:
The phases of the waveform patterns on different peripheral cutting edges are shifted relative to each other, creating asymmetric positioning of the foremost protrusion that prevents simultaneous sharp corner formation across all cutting edges, thereby reducing fracturing while maintaining manufacturability
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In a roughing end mill, a plurality of corner cutting edges (8) and a plurality of peripheral cutting edges (5) are formed at an outer periphery of a distal end portion of an end mill main body, a roughing part (9) having a waveform pattern of recesses and protrusions when viewed from the rotation direction of the end mill is formed in the peripheral cutting edge (5) of each of the chip discharge flutes (4), wherein a phase of the recesses and protrusions of the roughing part (9) of one chip discharge flute (4) is shifted with respect to that of the other chip discharge flute (4) adjacent to the one chip discharge flute (4) in the circumferential direction, a foremost protrusion (9A) of the roughing part (9) of one peripheral cutting edge (5) is located closer to a distal end of the end mill main body than those of the other peripheral cutting edges (5), a peak (9C) in a radial direction of the foremost protrusion (9A) of the one peripheral cutting edge (5) is aligned with another peak (8A) in the radial direction of the corner cutting edge (8) adjacent to the one peripheral cutting edge (5), or connected to the another peak (8A) in the radial direction of the corner cutting edge (8) by a straight portion (10) extending in a linear manner when viewed from the rotation direction of the end mill, and a peak (9C) in the radial direction of a foremost protrusion (9A) of the roughing part (9) of each of the other peripheral cutting edges (5) is connected to another peak (8A) in the radial direction of the corner cutting edge (8) adjacent to the other peripheral cutting edge (5) by another straight portion (10) extending in a linear manner when viewed from the rotation direction of the end mill.