Foil-Sheet Cleaning in Vat Photopolymer Printing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional additive manufacturing methods face challenges in achieving dimensional accuracy and uniformity due to residual cured or partially cured materials adhering to the build surface, which can disrupt the surface morphology and mechanical properties of printed components, and mechanical scraping or solvent-based cleaning can cause damage or contamination.
Innovation Solution
A method involving a transparent foil sheet and electromagnetic source to cure photopolymer resin, followed by a solvent-free cleaning process using an abrasive shear force from a moving foil sheet to remove partially cured materials, ensuring uniform surface finishes and material segregation between layers without mechanical damage or contamination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If mechanical scraping is used to clean the build surface, then residual cured materials are removed, but the printed part may be damaged or unintentionally removed from the build surface
Solution Approach 1:
The patent replaces mechanical scraping with a solvent-free cleaning process that uses a build plate moving through uncured photopolymer resin. The uncured resin acts as a lubricant and cleaning medium, allowing residual cured materials to be removed without mechanical contact that could damage the printed part.
Solution Approach 2:
The uncured photopolymer resin serves as an intermediary substance between the build plate and residual cured materials. As the build plate moves through the uncured resin, the resin penetrates and lifts away cured material residues without requiring direct mechanical scraping contact with the printed part surface.
2Manufacturing precision
If solvent-based cleaning is used to remove residual materials, then the build surface is cleaned, but contamination may occur and additional post-processing steps are required
Solution Approach 1:
The uncured photopolymer resin in the vat serves a dual function: it is both the building material for new layers and the cleaning medium for removing residual cured materials. This self-service approach eliminates the need for separate solvent-based cleaning processes and reduces overall process complexity.
Solution Approach 2:
The patent extracts and eliminates the need for separate cleaning solvents and post-processing steps by utilizing the existing uncured photopolymer resin in the vat as the cleaning medium, thereby simplifying the overall manufacturing process.
3Reliability
If the build plate moves through uncured photopolymer resin to clean the surface, then residual cured materials are removed without damage, but the cleaning mechanism requires precise control of build plate position and movement
Solution Approach 1:
The cleaning action occurs continuously as the build plate moves through the uncured photopolymer resin during the layer formation process. This continuous cleaning integrates with the additive manufacturing workflow without requiring separate discrete cleaning operations, simplifying control requirements.
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
Enhances the accuracy and uniformity of printed parts by removing partially cured materials effectively, maintaining mechanical properties and avoiding post-processing steps, while allowing for distinct material segregation between layers.
Implementation Method 1
Stereolithography is a type of additive manufacturing process which employs a liquid including a radiant-energy curable photopolymer resin and a curing energy source such as a laser
Implementation Method 2
translating the foil sheet along a second axis to clean the segment of the printed part within the cast layer
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method for cleaning an additively manufactured part, the method comprising: contacting a cast layer (102) with a build plate (110). The cast layer (102) is disposed on a first side (107) of a foil sheet (106) and has a surface height (124) spaced vertically above the foil sheet (106) along a first axis (122). The build plate (110) is vertically spaced above the foil sheet (106) along the first axis (122). The method includes moving the build plate (110) along the first axis (122) to position a build surface (114) at a cure depth (118) below the surface height (124) of the cast layer (102) to form a segment (116) of a printed part (112) on the build surface (114). The method includes moving the build plate (110) along the first axis (122) to position the segment (116) of the printed part above the cure depth (118) and translating the foil sheet (106) along a second axis (120) to clean the segment (116) of the printed part (112) within the cast layer (102).