Adjustable Eccentric Pendulum Drive for Milling Precision

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing milling machines lack precision when milling deep elongated holes or using long milling tools due to the compact design of the pendulum gear, which compromises the accuracy of the recess or slot milled into the workpiece.

Innovation Solution

The milling machine incorporates an adjustable eccentric device coupled to the pendulum lever, allowing for adjustment of the relative position of the eccentric bearing axis to the pendulum lever pivot axis, enabling precise setting of the pendulum lever amplitude through a guide link and stop mechanism, ensuring the center axis of the milling tool remains consistent across different amplitudes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If the pendulum gear is designed in a compact form, then the device complexity is reduced and the structure is simplified, but the manufacturing precision and accuracy of the milled recess deteriorate

Engineering Contradiction:
Improvestructure complexityVSAvoidmilling accuracy
Core Design Contradiction:
Device complexityVSManufacturing precision

Solution Approach 1:

The pendulum gear is divided into separate functional components: the pendulum lever, the eccentric device, and the guide link. This segmentation allows each component to be optimized independently - the eccentric device can be designed with precise adjustment mechanisms while the overall structure remains compact.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The eccentric device is made adjustable rather than fixed, allowing the distance between the eccentric bearing axis and pendulum lever pivot axis to be modified. This dynamic adjustment capability enables precise control of the pendulum lever amplitude, improving milling accuracy without requiring a larger overall structure.

Inventive Principle:
Principle #15Dynamics

2Measurement precision

If the distance between the eccentric bearing axis and pendulum lever pivot axis is increased, then the pendulum lever amplitude precision is improved, but the device complexity increases

Engineering Contradiction:
Improveamplitude setting precisionVSAvoidadjustment mechanism complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The guide link serves multiple functions: it guides the eccentric device, defines the pendulum lever amplitude through its geometry, and provides a reference axis for adjustment. This multi-functionality reduces the need for additional separate components that would increase complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The guide link acts as an intermediary element between the eccentric device and the pendulum lever. It translates the position of the eccentric bearing axis into a controlled pendulum lever amplitude, mediating the relationship between these components and enabling precise amplitude setting without direct complex coupling.

Inventive Principle:
Principle #24Intermediary (Mediator)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This configuration enhances the precision and accuracy of the milling process, particularly when milling deep elongated holes or using long tools, by allowing for high-precision adjustment of the pendulum lever amplitude, facilitating precise positioning of the milling tool relative to the workpiece.

Implementation Method 1

an eccentric device (90) which can be adjusted by the adjustment device (107) relative to the pendulum lever (98), so that a large distance between an eccentric bearing axis (85) and the pendulum lever pivot axis (100) is available or adjustable

Methodology Applied
Scientific EffectEccentric mechanism: Eccentric

Data Source

PatentEP2527111B1Milling machine with an oscillating drive
Publication Date: 2013.06.19 FESTOOL GMBH
  • EP2527111B1 patent drawingFigure 1
  • EP2527111B1 patent drawingFigure 2
  • EP2527111B1 patent drawingFigure 3a~3b

AI summary

The machine has a pendulum drive (51) including a pendulum lever (98), which is driven by an eccentric device (90) in a pendulum lever-oscillation movement. An adjusting device (107) adjusts larger and smaller pendulum lever amplitudes of the pendulum lever-oscillation movement. The eccentric device includes an eccentric unit (92), which rotates around an eccentric bearing axis and acts on the lever. The adjusting device is movingly coupled with the eccentric device for adjusting a relative position of the bearing axis to a pendulum lever pivot axis (100) for adjusting the amplitudes.