Milling Tool Body Assembly With Locking Disc for Low Run-Out

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing milling tool bodies suffer from vibrations and axial/radial run-out due to manufacturing tolerances and centralized coupling forces, leading to reduced machining precision and increased wear on cutting inserts.

Innovation Solution

A milling tool body design with a constant diameter central through-hole and a locking disc that distributes compressive forces radially, eliminating the need for internal shoulders and allowing for single-sided manufacturing, thereby reducing vibrations and run-out.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If separate drilling and milling operations are performed from both front and rear end surfaces to create parts of different diameters, then the milling tool body can be mounted to the adaptor, but manufacturing tolerances lead to non-concentric parts causing vibrations during rotation

Engineering Contradiction:
Improvemounting capabilityVSAvoidconcentricity
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent divides the mounting function into two separate components: a through-hole of constant diameter for rotational alignment and a locking disc for securing the tool body to the adaptor. This segmentation eliminates the need for complex multi-step drilling and milling operations that compromise concentricity, while maintaining ease of manufacture through simpler single-sided operations.

Inventive Principle:
Principle #1Segmentation

2Strength

If a screw head presses directly on an internal shoulder surface, then the milling tool body can be fastened to the adaptor, but the centrally applied coupling force induces elastic deformation and bending causing axial and radial run-out

Engineering Contradiction:
Improvefastening forceVSAvoidposition accuracy of cutting inserts
Core Design Contradiction:
StrengthVSManufacturing precision

Solution Approach 1:

The patent extracts the force application function from the central through-hole region and relocates it to the locking disc positioned at the periphery of the milling tool body. This extraction prevents the screw from directly pressing on internal shoulder surfaces, eliminating the source of elastic deformation and bending that cause run-out, while maintaining adequate fastening strength through the locking disc mechanism.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent transitions from centralized force application in the axial dimension to distributed peripheral force application in the radial dimension through the locking disc. This dimensional change moves the coupling force from the center to the periphery, preventing elastic deformation and bending of the tool body that would otherwise occur with central loading.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Reliability

If internal shoulders and coolant chambers are manufactured with complex multi-sided operations, then mounting and cooling functions are achieved, but manufacturing complexity and time increase

Engineering Contradiction:
Improvemounting and cooling functionVSAvoidmanufacturing cycle time
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent extracts the coolant chamber function from the complex multi-sided drilling and milling operations and replaces it with a through-hole of constant diameter that can be manufactured in a single operation from one side. The locking disc is similarly extracted as a separate component that simplifies the mounting function, eliminating the need for complex internal shoulder formation and significantly reducing manufacturing cycle time while maintaining reliability.

Inventive Principle:
Principle #2Taking out (Extraction)

Data Source

PatentEP3785833B1Assembly with milling tool body
Publication Date: 2024.02.28 SANDVIK COROMANT
  • EP3785833B1 patent drawingFigure 1a~1c
  • EP3785833B1 patent drawingFigure 2~3
  • EP3785833B1 patent drawingFigure 4

AI summary

The invention relates to a milling tool body (1) being rotatable around a central rotation axis (R). The milling tool body (1) has a front end surface (2) and a rear end surface (3), wherein an envelope surface (4) surrounds the central rotation axis (R) and extends between the rear end surface (3) and the front end surface (2). A plurality of insert pockets (5) are formed in a transition between the envelope surface (4) and the front end surface (2). A first central through-hole (6) of constant diameter extends between the rear end surface (3) and the front surface (2). The milling tool body (1) includes a locking disc (7) with a second central through-hole (8) and a fastening device (9) arranged to extend through the second central through-hole (8) of the locking disc (7). The locking disc (7) is arranged to press against the front end surface (2) of the milling tool body (1) when mounting the milling tool body (1) to an adaptor (10) by the fastening device (9) being mountable to an end (11) of the adaptor (10) insertable into the first central through-hole (6) of the milling tool body (1).