Method and apparatus for three-dimensional printing

• US 8,147,910 B2
• Filed: 02/24/2009
• Issued: 04/03/2012
• Est. Priority Date: 02/24/2009
• Status: Active Grant

• Current Assignee: Stratasys Incorporated
• Original Assignee: Objet Ltd. (Stratasys Incorporated)
• Inventors: Kritchman, Eliahu M.
• Primary Examiner(s): PARKER, FREDERICK JOHN
• Application Number:
  US12/391,964
• Publication Number:
  US 20100215856A1
• Time in Patent Office: 1,134 Days
• Field of Search: 427/258, 264/308
• US Class Current: 427/258
• CPC Class Codes: B29C 64/112 using individual droplets, e.g. from jetting heads
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 70/00 Materials specially adapted for additive manufacturing

Abstract

Embodiments of the invention are directed to a system and method to fabricate three-dimensional objects, layer by layer, by selectively dispensing material from a printing head onto a transfer platform to form a cross-sectional layer of the object that has a pre-determined non-uniform surface. Each layer may then be transferred from the transfer platform to previously formed layers that are carried by a fabrication platform by contacting an exposed surface of a previously formed layer to the layer on the transfer platform.

Claims

1. A method of producing, layer by layer, three-dimensional objects, the method comprising:

selectively dispensing material, layer by layer, from a printing head onto a transfer platform, each layer corresponding to a cross section of a three-dimensional object to be formed;

transferring, layer by layer, each layer from the transfer platform to a fabrication platform prior to depositing a subsequent layer on the transfer platform until the three-dimensional object is formed,

wherein a deposited layer is designed to have a non-uniform thickness.

2. The method of claim 1,

wherein the non-uniform thickness eliminates the need for use of a leveling device prior to transferring the deposited layer to the fabrication platform.

3. The method of claim 1,

wherein the deposited layer is designed to have scattered areas having a thickness smaller than an incremental step by which a distance between a bottom surface of the fabrication platform and a top surface of the transfer platform increases after each layer transfer, and other areas having a thickness larger than an incremental step.

4. The method of claim 1, wherein the non-uniform thickness of the layer is formed by dispensing the material at different rates.

5. The method of claim 1, comprising dispensing the material based on printing information for the deposited layer such that the deposited layer is defined by a matrix of pixels and wherein selectively dispensing material comprises dispensing different amounts of material at different of pixels.

6. The method of claim 1, wherein the deposited layer comprises a non-uniform surface in the form of peaks and valleys.

7. The method of claim 6, wherein the peaks and valleys are formed by dispensing material from the printing head at a variable flow rate.

8. The method of claim 6, wherein the peaks and valleys are formed by dispensing material from the printing head at a plurality of passes.

9. The method of 1, wherein the material is a photopolymer.

10. The method of 1, wherein the material is a wax material.

11. The method of 1, wherein a non-uniform surface of the deposited layer becomes uniform as a result of contacting the non-uniform surface to a surface of a previously formed layer, wherein the previously formed layer is carried by the fabrication platform.

12. The method of 1, wherein a portion of material from the peaks is squeezed into the valleys during attachment of the deposited material to a previously formed layer.

13. The method of 1, wherein the deposited layer is designed such that the thickness in a circumference of the deposited layer is larger than the thickness in adjacent areas.

14. The method of 1, wherein said layer is at least partially solidified before being transferred.

15. The method of 1, wherein said layer comprises more than one dispensed material.