Cutting Head Interface With Conical Bearing Surfaces for Accurate Milling

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current ball raceway milling devices face challenges in providing a stable and accurate interface between the holder and cutting head, which is subjected to high flexural stress due to angled settings, leading to potential losses in tool accuracy.

Innovation Solution

The tool features a unique interface with conical and axial bearing surfaces, where the cutting head is secured via internal and external threads, with conical surfaces providing improved centering and force absorption in both axial and radial directions, enhancing stability and accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the cutting head is set at an angle for ball raceway milling, then the tool can machine raceways at different engagement widths and depths, but the interface between holder and cutting head is subjected to high flexural stress which compromises positioning accuracy

Engineering Contradiction:

Improveability to machine raceways at different engagement widths and depthsVSAvoidpositioning accuracy of cutting head

Core Design Contradiction:

Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The patent employs conical bearing surfaces instead of cylindrical ones, utilizing the curved geometry to provide both centering and force absorption capabilities. The conical shape allows the interface to accommodate flexural stresses while maintaining precise positioning through the geometric constraints of the tapered surfaces.

Inventive Principle:

Principle #14Spheroidality (Curvature)

Solution Approach 2:

The invention transitions from a simple cylindrical interface to a multi-surface conical interface that engages in multiple dimensions. The conical bearing surfaces provide radial centering while simultaneously absorbing axial and radial forces, adding dimensional complexity to the interface design to resolve the contradiction between adaptability and precision.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Ease of manufacture

If a simple cylindrical interface is used between holder and cutting head, then the structure is simple and easy to manufacture, but it cannot adequately absorb flexural stress and maintain positioning accuracy

Engineering Contradiction:

Improvesimplicity of interface structureVSAvoidstability and accuracy of tool interface

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The conical bearing surfaces replace simple cylindrical surfaces, using curved geometry to simultaneously achieve centering and force absorption functions that a cylindrical interface cannot provide, thereby improving reliability without significantly complicating manufacturing.

Inventive Principle:

Principle #14Spheroidality (Curvature)

Solution Approach 2:

The interface is segmented into distinct functional surfaces: conical bearing surfaces for centering and force absorption, and axial bearing surfaces for positioning. This segmentation allows each surface to be optimized for its specific function while maintaining overall manufacturing feasibility.

Inventive Principle:

Principle #1Segmentation

3Device complexity

If conventional interfaces are used, then the tool structure remains simple, but wear occurs at the interface which reduces tool longevity and accuracy

Engineering Contradiction:

Improvecomplexity of interface structureVSAvoidlongevity and accuracy of tool

Core Design Contradiction:

Device complexityVSDuration of action of stationary object

Solution Approach 1:

The conical bearing surfaces distribute contact stresses over a larger area compared to cylindrical interfaces, reducing localized wear. The curved geometry inherently provides better load distribution, extending the service life of the interface while maintaining structural simplicity.

Inventive Principle:

Principle #14Spheroidality (Curvature)

Solution Approach 2:

The conical surfaces are designed to establish proper centering and force absorption from the initial engagement, preventing misalignment and excessive localized stresses that would accelerate wear. This preliminary proper engagement protects the interface throughout the tool's service life.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS11801562B2Tool for machining a workpiece

Publication Date: 2023.10.31 HARTMETALL WERKZEUGFAB PAUL HORN

AI summary

The present invention relates to a tool (10) for machining a workpiece, comprising a cutting head (12) which comprises a sleeve (16) and a cutting element (18) which is fixed to the sleeve (16), and comprising a holder (14) to which the cutting head (12) can be detachably fixed. In an assembled state of the tool (10), the cutting head (12) and holder (14) are screwed to each other via an internal thread (40) which is arranged in the sleeve (16) and an external thread (42) which corresponds thereto and which is arranged on the holder (14). In addition, in the assembled state of the tool (10), the cutting head (12) and holder (14) contact each other along a first axial bearing surface (36) which is arranged on the sleeve (16) and a second axial bearing surface (38) which corresponds thereto and which is arranged on the holder (14), and along a first conical bearing surface (44) which is arranged on the sleeve (16) and a second conical bearing surface (46) which corresponds thereto and which is arranged on the holder (14).