Hydrostatic Bearing Retaining Device for Workpiece Deviation Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing machine tools with hydrostatic bearings struggle to maintain precise support and reduce shape and positional deviations of workpieces, especially during extended machining times, due to contamination of the bearing liquid by cooling lubricant, leading to instability and potential damage.

Innovation Solution

A retaining device is provided to prevent contamination of the hydrostatic bearing liquid by the cooling lubricant, using an elastic seal attached to the workpiece and the machine tool's carrier, forming a liquid-tight enclosure around the hydrostatic bearing, and incorporating a joint bearing for adaptable support and sensors for real-time adjustments.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If cooling lubricant is applied during machining, then cooling and lubrication of the tool and workpiece are improved, but the bearing liquid in the hydrostatic bearing becomes contaminated, leading to reduced precision and potential damage

Engineering Contradiction:
Improvecooling effectVSAvoidbearing liquid purity
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The machine tool system is divided into separate functional zones: a machining zone where cooling lubricant is applied, and a bearing zone where the hydrostatic bearing operates with pure bearing liquid. The retaining device creates a physical segmentation between these zones, allowing both cooling lubrication and precise hydrostatic bearing to function simultaneously without interference.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The harmful factor (cooling lubricant) is extracted from the bearing zone by introducing it only in the machining area. The retaining device ensures that cooling lubricant is applied exclusively where needed for tool cooling and workpiece lubrication, while being prevented from entering the hydrostatic bearing area, thus protecting the bearing liquid purity.

Inventive Principle:
Principle #2Taking out (Extraction)

2Manufacturing precision

If machining time is extended to reduce shape and positional deviations, then manufacturing precision is improved, but the bearing liquid becomes increasingly contaminated, leading to method instability

Engineering Contradiction:
Improveshape and positional deviation reductionVSAvoidmachining time
Core Design Contradiction:
Manufacturing precisionVSDuration of action of moving object

Solution Approach 1:

The retaining device acts as an intermediary barrier between the cooling lubricant application system and the hydrostatic bearing system. This intermediary structure allows the machining process to proceed for extended durations with cooling lubricant application while maintaining the purity of the bearing liquid, thus enabling long machining times without compromising bearing performance or method stability.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If a retaining device is introduced to prevent contamination, then bearing liquid purity is maintained, but device complexity increases

Engineering Contradiction:
Improvebearing liquid protectionVSAvoidstructure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The retaining device utilizes flexible retaining elements that can be configured as thin barriers or seals to prevent contamination. These flexible components adapt to the geometry of the machine tool structure, providing effective contamination protection while maintaining a relatively simple and compact device design that integrates smoothly with existing machine tool components.

Inventive Principle:
Principle #30Flexible shells and thin films

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 solution ensures precise and stable hydrostatic support of workpieces, reducing shape and positional deviations, even during long machining processes, while preventing contamination and enhancing the machine tool's accuracy and longevity.

Implementation Method 1

a bearing liquid for at least partially hydrostatic bearing of the workpiece is introduced

Methodology Applied
Scientific EffectHydrostatic bearing: Lubrication

Implementation Method 2

a retaining device is provided to avoid contamination of the storage liquid by mixing it with cooling lubricant, with this retaining device being at least partially attached to the workpiece, in particular via a elastic seal

Methodology Applied
Scientific EffectElastic sealing: Elasticity

Data Source

PatentEP2415557B1Device and method for reducing deviations in shape and/or position, in particular the run out of a workpiece
Publication Date: 2014.12.10 WFL MILLTURN TECH
  • EP2415557B1 patent drawingFigure 1
  • EP2415557B1 patent drawingFigure 2
  • EP2415557B1 patent drawingFigure 3

AI summary

The method involves fixing a work piece (7) in a machine tool and supporting the work piece over shells (4-6) of a bezel (1) that is attached at the tool. The work piece is processed by a tool of the machine tool under partial supply of coolant. Storage liquid for partial hydrostatic storage of the work piece is brought between one of the shells and the work piece during processing of shape- and/or position deviations of the work piece. A restraint device is provided for avoiding contamination of the fluid by the coolant during the processing. An independent claim is also included for a machine tool comprising a bezel.