Tapered End Mill Flute Geometry for Chip Discharge and Strength
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Tapered end mills face a challenge in achieving high chip discharge performance while maintaining strength and rigidity, as reducing web thickness for improved chip discharge can lead to tool breakage under high machining loads.
Innovation Solution
A tapered end mill design with a flute bottom radius that linearly changes at a predetermined gradient angle, where the gradient angle on the tool tip side is smaller than on the shank side, ensuring reduced web thickness for improved chip discharge without compromising strength and rigidity, and featuring helical flutes to disperse load and enhance chip flow.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the web thickness is reduced to improve chip discharge performance, then chip discharge performance is improved, but the strength and rigidity decrease causing tool breakage under high machining loads
Solution Approach 1:
The patent applies local quality by varying the flute bottom radius along the tool length. The flute bottom radius is smaller at the tool tip side (reducing web thickness for improved chip discharge) and larger at the shank side (maintaining web thickness for strength and rigidity). This gradient distribution allows each region to have optimal properties for its specific function.
Solution Approach 2:
The patent changes the geometric parameter of the flute bottom radius continuously along the tool axis. By controlling the gradient angle of the flute bottom radius to be within a specific range (0° to 15°), the web thickness is optimized to balance chip discharge performance and structural strength, preventing tool breakage while improving chip flow.
2Strength
If a step is formed in the flute bottom radius to reduce web thickness on the tool tip side, then strength and rigidity are ensured on the shank side, but the step hinders chip discharge performance
Solution Approach 1:
The patent replaces the stepped (discontinuous) structure with a curved (continuous) structure. The flute bottom radius changes gradually along the tool length with a controlled gradient angle, eliminating abrupt steps that would impede chip flow. This continuous curvature allows chips to discharge smoothly while still achieving the desired web thickness reduction at the tool tip.
Data Source
AI summary
A tapered end mill includes an outer circumferential cutting edge, a flute is disposed such that a flute bottom radius defined as a distance between a flute bottom and the tool axis decreases from a shank side toward the tool tip side, the flute bottom radius linearly changes at a predetermined gradient angle in the tool axis direction, the gradient angle changes at a predetermined change point to become smaller on the tool tip side as compared to the shank side, and a gradient angle θ1 on the tool tip side relative to the change point is equal to or larger than 0° and smaller than a taper half angle α of a cutting portion provided with the outer circumferential cutting edge, and a gradient angle θ2 on the shank side relative to the change point is larger than the taper half angle α.