Machine Tool Thermal Deformation Compensation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

High-precision mechanical machining operations in uncontrolled temperature and humidity environments, such as cold or humid regions, lead to thermal deformations in machine tools, affecting the accuracy of machining due to deformations in the measuring means like optical lines or linear encoders.

Innovation Solution

A machine tool with a system that includes temperature sensors along the optical line to detect temperature changes and generate correction signals for the translation control, using a management system connected to the control means of the translation of the upright base, accounting for the linear heat expansion coefficient of the optical line, and a thermally separated feeler to determine movement corrections.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If machining operations are performed in uncontrolled temperature environments, then the machine tool can operate in cold or humid regions, but thermal deformations occur in the measuring means causing loss of precision

Engineering Contradiction:
Improveability to operate in uncontrolled environmentsVSAvoidprecision of measuring means
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

Temperature sensors are installed along the optical line to continuously monitor temperature variations. The control system receives temperature data and automatically calculates compensation values based on the thermal expansion coefficient, applying corrections to the measured positions to maintain precision despite temperature changes

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system changes the measurement parameters by introducing temperature-dependent correction factors. The control system adjusts the measured position values based on detected temperature variations and the known thermal expansion coefficient of the optical line, effectively compensating for thermal deformations

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If temperature sensors and correction systems are added to compensate for thermal deformations, then measurement precision is maintained, but device complexity increases

Engineering Contradiction:
Improveprecision of measuring meansVSAvoidcomplexity of compensation system
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The system replaces complex mechanical thermal compensation mechanisms with an electronic/software-based solution. Temperature sensors provide data to a control system that calculates and applies corrections algorithmically, avoiding the need for complex mechanical adjustment devices while maintaining measurement precision

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

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 increases the precision of machining operations by effectively compensating for heat deformations, reducing imprecision caused by temperature fluctuations and maintaining high accuracy in uncontrolled environments.

Implementation Method 1

a system (30) suitable for detecting the temperature of the optical line (20) and generating correction signals (23) for the control means (18) of the translation of the upright base (4), according to at least one temperature read along said optical line (20) and according to the linear heat expansion coefficient of the optical line (20)

Methodology Applied
Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentEP2678134B1Machine tool with thermal deformation compensation of measuring means
Publication Date: 2018.06.20 INNSE BERARDI SPA
  • EP2678134B1 patent drawingFigure 1~3
  • EP2678134B1 patent drawingFigure 4~5
  • EP2678134B1 patent drawingFigure 6~9

AI summary

A machine tool, e.g., of large dimensions, comprises a j bench (2), an upright base (4), control means of the translation of the upright base, an upright base position sensor comprising an optical line or linear encoder (20) fixed to the bench (2), means for detecting the temperature (T1,...,Tn) of the optical line and management means (30) for processing the temperature signals coming from the optical line temperature detection means and the signals of the upright base translation control means to determine a correction signal for the upright base translation control means according to at least one temperature detected along the optical line.