3D Printer Laser Convergence Calibration Using Acoustic Analysis

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing 3D printing systems face challenges in properly converging an energy beam at the build plane during the layer-by-layer fabrication of three-dimensional articles using powdered materials, affecting productivity and accuracy.

Innovation Solution

A method and apparatus that calibrate the convergence of a radiation beam by vertically translating a metal platen within a build chamber, using an acoustic sensor to determine the height of maximum laser convergence and adjusting it to match the build plane height, while maintaining an appropriate gas environment for optimal calibration and fabrication.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If traditional methods are used to converge the energy beam, then the system structure remains simple, but the beam convergence precision at the build plane is insufficient

Engineering Contradiction:
Improvebeam convergence precisionVSAvoidsystem complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent introduces an acoustic sensor as an intermediary element to detect and measure beam convergence. The sensor acts as a mediator between the laser system and the build plane, providing real-time feedback on beam focus quality without requiring complex mechanical adjustment mechanisms. This allows precise beam convergence measurement while maintaining relatively simple system architecture.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces traditional mechanical methods of beam convergence adjustment and measurement with an acoustic field-based approach. Instead of using mechanical sensors or complex optical alignment systems, the invention uses acoustic signals generated by material consolidation to indirectly measure and optimize beam convergence, substituting mechanical measurement systems with a non-contact acoustic detection method.

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

2Productivity

If multiple energy beams are used to increase productivity, then the manufacturing output improves, but the difficulty of properly converging each beam at the build plane increases

Engineering Contradiction:
Improvemanufacturing outputVSAvoidbeam convergence detection difficulty
Core Design Contradiction:
ProductivityVSDifficulty of detecting and measuring

Solution Approach 1:

The acoustic sensor system serves multiple functions simultaneously: it detects beam convergence for each energy beam, monitors material consolidation quality, and provides feedback for real-time beam adjustment. This multi-functional approach allows the system to handle multiple beams with a single detection mechanism, reducing the overall complexity of measuring and controlling each individual beam's convergence.

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

Solution Approach 2:

The material consolidation process itself generates the acoustic signals used for measurement. The consolidated material acts as its own sensor, producing acoustic emissions that naturally indicate the quality of beam convergence and energy coupling. This self-service mechanism eliminates the need for separate, complex external measurement systems for each beam.

Inventive Principle:
Principle #25Self-service

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 approach ensures precise beam convergence, enhancing the accuracy and productivity of the 3D printing process by optimizing the energy beam focus at the build plane, leading to improved fabrication of three-dimensional articles.

Implementation Method 1

an acoustic sensor that is positioned within the build chamber... receiving a signal from the acoustic sensor... determining a height of maximum laser convergence for the platen

Methodology Applied
Scientific EffectAcoustic emission: Acoustic Emission

Data Source

PatentEP3771548B1Three-dimensional printing system with laser convergence calibration based upon acoustic analysis
Publication Date: 2023.10.04 LAYERWISE
  • EP3771548B1 patent drawingFigure 1~2
  • EP3771548B1 patent drawingFigure 3~4
  • EP3771548B1 patent drawingFigure 5

AI summary

A method of manufacturing a three-dimensional article includes: (1) Loading a metal platen into a build chamber, the metal platen defines an upper surface; (2) Performing concurrent processes including operating a movement mechanism to vertically translate the platen, operating a laser system to impinge a radiation beam upon the upper surface of the platen, and receiving a signal from an acoustic sensor that is positioned within the build chamber; (3) Analyzing the signal including determining a height of optimal laser convergence for the platen; and (4) Based upon the analysis, adjusting the laser convergence height to a build plane height.