Systems for preventing oxygen inhibition of a light-initiated polymerization reaction in a 3D printing system using uniform planar surfaces

Patent metadata

Field	Value
Publication number	US-11590701-B2
Application number	US-202217819279-A
Country	US
Kind code	B2
Filing date	Aug 11, 2022
Priority date	Dec 11, 2018
Publication date	Feb 28, 2023
Grant date	Feb 28, 2023

Abstract

Systems and methods that prevent oxygen inhibition of a light-initiated polymerization reaction by forcing the oxygen away from the reaction surfaces. In some embodiments, oxygen is purged by bringing a planarizing surface (e.g., a thin transparent film and/or a transparent planar surface) into contact with a layer of UV curable material disposed on a workpiece and then moving the planarizing surface away from the workpiece one the UV material is cured.

First claim

What is claimed is:

1. A system for preventing oxygen inhibition of a light-initiated polymerization reaction at ambient conditions, said system comprising:
a first light source for emitting ultraviolet (UV) light;
a UV curing space for accepting a workpiece with a layer of UV curable material on the workpiece;
means for purging oxygen from the UV curing space to facilitate, within the UV curing space, UV curing of the layer of UV curable material on the workpiece at times when the first light source emits the UV light onto the layer of UV curable material, wherein the means for purging oxygen includes a UV-transparent surface to planarize the layer of UV curable material and wherein the UV-transparent surface comprises a thin film in tension, a plate of solid material, or a combination of the thin film in tension and the plate of solid material;
a camera arranged to evaluate reflective properties of the UV-transparent surface so as to determine whether contact has been achieved between the layer of UV curable material on the workpiece and the UV-transparent surface while the layer of UV curable material on the workpiece has not yet been cured by the first light source; and
a height sensor for detecting a height of the workpiece, the height sensor comprising a second light source for emitting a beam of light and a detector for detecting the beam of light, the second light source and detector arranged on opposite sides of the workpiece and adjacent to the UV-transparent surface such that detection of the beam of light by the detector indicates that the workpiece has not yet been raised to an appropriate height for UV curing of the UV curable material to begin, and failure to detect the beam of light by the detector indicates that the workpiece has been raised to the appropriate height for the UV curing of the UV curable material to begin.

2. The system of claim 1 , further comprising means for removing the UV-transparent surface from contact with a cured UV-curable layer of the workpiece.

3. The system of claim 2 , wherein the UV-transparent surface comprises the thin film in tension.

4. The system of claim 3 , wherein the thin film is unwound from a first reel and is wound on a second reel.

5. The system of claim 3 , wherein the means for removing comprises a pair of rollers configured to keep the thin film in tension during a removal process.

6. The system of claim 5 , wherein the means for removing further comprises an arm on which the pair of rollers is mounted.

7. The system of claim 6 , wherein the means for removing further comprises a piston for raising or lowering the arm.

8. The system of claim 1 , wherein the UV-transparent surface comprises a plate of solid material.

9. The system of claim 1 , wherein the UV-transparent surface comprises the combination of the thin film in tension and the plate of solid material.

10. The system of claim 9 , further comprising an arm for placing the plate of solid material on the thin film in tension and removing the plate of solid material from the thin film in tension.

11. The system of claim 1 , wherein the camera is configured to detect infra-red light that is reflected from the UV-transparent surface.

12. The system of claim 1 , wherein the beam of light comprises infra-red light.

13. The system of claim 1 , wherein the detector is configured to detect infra-red light that is present in the beam of light.

14. The system of claim 1 , wherein the first light source comprises a first UV light emitting diode (LED) light module and a second UV LED light module.

15. The system of claim 14 , wherein the camera is disposed between the first UV LED light module and the second UV LED light module.

16. The system of claim 1 , wherein the UV curing space is disposed between the camera and the workpiece.

17. The system of claim 1 , wherein the UV curing space is disposed between the first light source and the workpiece.

Assignees

• Io Tech Group Ltd

Inventors

• Zenou Michael
• Gilan Ziv
• Liptz Daniel
• Shai Yuval

Classifications

• B33Y40/00

  Auxiliary operations or equipment, e.g. for material handling · CPC title

• B33Y10/00

  Processes of additive manufacturing · CPC title

• B29C64/106

  using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material · CPC title

• B29C64/264 Primary

  Arrangements for irradiation · CPC title

• B29C35/0805

  using electromagnetic radiation · CPC title