3D Printer Inkjet Detection Using Profilometer Test Patterns

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Three-dimensional printers face inefficiencies due to inoperative inkjets, which cannot be detected until the printing process is complete, leading to malformed objects and reduced product yield.

Innovation Solution

An apparatus comprising a profilometer and a controller that detects inoperative inkjets by generating measurements of material drops on a planar member, allowing for real-time identification and remedial action during printing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If printing continues without inkjet detection, then productivity is maintained, but manufacturing precision deteriorates due to undetected inoperative inkjets

Engineering Contradiction:
Improveprinting efficiencyVSAvoidobject quality
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The system performs preliminary detection of inkjet functionality by printing test patterns before production printing and periodically during printing. The profilometer scans the test patterns to identify inoperative inkjets in advance, allowing corrective action before defective objects are produced, thus maintaining both productivity and manufacturing precision.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system establishes a feedback loop where the profilometer continuously monitors test patterns printed by the printhead, detects deviations indicating inoperative inkjets, and provides real-time feedback to the controller. This enables dynamic adjustment or interruption of printing to maintain object quality without significant productivity loss.

Inventive Principle:
Principle #23Feedback

2Manufacturing precision

If inkjet detection is implemented during printing, then manufacturing precision is improved, but device complexity increases

Engineering Contradiction:
Improveinkjet functionality detectionVSAvoidsystem structure
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The profilometer serves multiple functions: it measures test patterns for inkjet detection, characterizes drop morphology for material properties analysis, and can potentially measure other print quality parameters. This multi-functionality reduces the need for separate specialized devices, thereby limiting the increase in device complexity while achieving precise inkjet detection.

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

Solution Approach 2:

The system uses its own printing mechanism to generate test patterns for detection, eliminating the need for external test equipment. The printhead prints both production objects and detection test patterns, and the profilometer uses reflected light from these patterns to detect inkjet issues, making the system self-diagnosing without adding external complexity.

Inventive Principle:
Principle #25Self-service

3Measurement precision

If test pattern printing is performed, then measurement precision is improved, but loss of time increases due to additional printing steps

Engineering Contradiction:
Improveinkjet detection accuracyVSAvoiddetection process time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The system merges the production printing process with the detection process by printing test patterns in the same build volume and using the same printhead. The test patterns are printed on dedicated support structures or unused portions of the build plate, combining quality assurance activities with production activities, thereby improving measurement precision without significant additional time loss.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The profilometer scanning and test pattern printing are performed continuously during or between production layers without interrupting the overall printing process. Detection activities are integrated into the printing workflow, maintaining continuous useful action rather than stopping production for separate detection operations, thus balancing measurement precision with time efficiency.

Inventive Principle:
Principle #20Continuity of useful action

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

Enables the detection and remediation of inoperative inkjets during the printing process, improving product yield and efficiency by ensuring proper object formation without completing the print job.

Implementation Method 1

a profilometer positioned adjacent a planar member located to receive drops of material ejected from inkjets in a printhead, the profilometer being configured to generate measurements of drops ejected onto the planar member

Methodology Applied
Scientific EffectProfilometry:

Data Source

PatentUS10005303B2System for detecting inoperative inkjets in three-dimensional object printing using a profilometer and predetermined test pattern printing
Publication Date: 2018.06.26 GENESEE VALLEY INNOVATIONS LLC

AI summary

A printer detects inoperative inkjets during printing of three-dimensional objects. The printer includes an area where a printhead ejects material in a predetermined pattern and a profilometer is operated to measure the ejected material in the area. The measurements are used to identify inoperative inkjets or inkjets that operate errantly.