Additive manufacturing method and apparatus for the production of dental crowns and other objects

Patent metadata

Field	Value
Publication number	US-2022088861-A1
Application number	US-202017594007-A
Country	US
Kind code	A1
Filing date	Apr 23, 2020
Priority date	Jun 18, 2019
Publication date	Mar 24, 2022
Grant date	—

Abstract

The present disclosure describes an additive manufacturing apparatus. The apparatus includes a chamber (11) having a planar circumferential top edge portion (12) defining a chamber orifice (13); a stage (15) movably positioned in the chamber (11), the two together configured to receive a viscous resin; a dispenser (30) facing the stage (15) and operatively associated therewith, the dispenser (30) configured to apply a planar coating of viscous resin; a primary drive (22) operatively associated with the dispenser (30) and chamber (11), the primary drive (22) configured to move the dispenser (30) across the chamber orifice (13); a light engine (40) facing the stage (15) and operatively associated therewith, the light engine (40) configured to expose a coating of resin on the stage (15) planar top surface (12) to patterned light; and a stage drive (24) operatively associated with the stage (15) and configured to retract the stage (15) into the chamber (11), following exposure of a coating of resin. Methods of making a three-dimensional object by additive manufacturing are also described.

First claim

1 . An additive manufacturing apparatus, comprising:
a chamber having a planar circumferential top edge portion defining a chamber orifice; a stage movably positioned in said chamber, said stage having a planar top surface portion alignable with said chamber planar circumferential edge portion, the two together configured to receive a viscous resin; a dispenser facing said stage and operatively associated therewith, said dispenser configured to apply a planar coating of viscous resin to said stage planar top surface portion; a primary drive operatively associated with said dispenser and said chamber, said primary drive configured to move said dispenser across said chamber orifice; a light engine facing said stage and operatively associated therewith, said light engine configured to expose a coating of resin on said stage planar top surface to patterned light; and a stage drive operatively associated with said stage and configured to retract said stage into said chamber, following exposure of a coating of resin on said stage to patterned light; a resin reservoir; an applicator roller operatively associated with said reservoir; and a roller drive operatively associated with said applicator roller, wherein said applicator roller and roller drive are configured to be reversible between:
(i) a first direction in which resin is pumped from said reservoir onto said stage (while said dispenser is optionally but preferably stationary); and
(ii) a second (preferably counter-rotating) direction in which excess resin is pumped from said stage into said reservoir while said dispenser moves across said chamber orifice to provide a smooth planar coating of said resin on said stage for subsequent exposure to patterned light.

2 .- 3 . (canceled)

4 . The apparatus of claim 1 , wherein said light engine is positioned above said stage.

5 . The apparatus of claim 1 , wherein said light engine is fixed and stationary.

6 . The apparatus of claim 1 , wherein said chamber is fixed and stationary.

7 . The apparatus of claim 1 , wherein said light engine comprises an ultraviolet (UV) light source.

8 . The apparatus of claim 1 , wherein said applicator roller is configured to completely span said chamber orifice.

9 . The apparatus of claim 1 , wherein said resin comprises a pseudoplastic paste.

10 . A method of making a three-dimensional object by additive manufacturing, comprising:
(a) providing a chamber having a planar circumferential top edge portion defining a chamber orifice with a stage movably positioned in said chamber, said stage having a planar top surface portion alignable with said chamber planar circumferential edge portion, the two together configured to receive a viscous resin; (b) retracting said stage into said chamber; and (c) dispensing a portion of resin onto said stage (before or after said retracting step), wherein said dispensing step is carried out by pumping resin from a reservoir with an applicator roller; then (d) smoothing said dispensed resin on said stage to form a planar coating of resin thereon, wherein said smoothing step is carried out by passing said applicator roller across said stage while counter-rotating said applicator roller; (e) exposing said coating of resin to patterned light to form a hardened coating of said resin; (f) repeating steps (b) through (e) with successive portions of resin deposited onto each previously hardened coating until said object is formed.

11 . (canceled)

12 . The method of claim 8 , wherein said applicator roller is positioned during said dispensing step so that resin is scraped from said applicator roller onto said stage by said chamber top edge portion.

13 . (canceled)

14 . The method of claim 8 , wherein said smoothing step is carried out with said applicator roller rotating with a tangential velocity at least 2, 3, 4 or 5 times greater than the speed at which said applicator roller is passed across said stage.

15 . The method of claim 8 , wherein said smoothing step is carried out with said applicator roller completely spanning said chamber orifice.

16 . The method of claim 8 , wherein said resin comprises an organic or inorganic particulate filler (e.g., sinterable particles such as metal particles, polymer particles, ceramic particles, etc., including combinations thereof) in combination with a photopolymerizable organic liquid matrix (e.g., with the inorganic filler included in the resin in an amount of about 50 or 60 percent by weight to about 80 percent by weight, or more).

17 . The method of claim 8 , wherein said resin comprises a pseudoplastic paste.

18 . The method of claim 8 , wherein said object comprises a dental crown, dental bridge, or dental implant.

19 . The method of claim 8 , wherein said object is comprised of ceramic.

Assignees

• Carbon Inc

Inventors

• Rademacher Soren
• Shirvanyants David
• Land Stephen Paul
• Bibb Iii Henry Quarles
• Ermoshkin Alexander

Classifications

• B29C64/232

  for motion along the axis orthogonal to the plane of a layer · CPC title

• B29C64/218

  Rollers · CPC title

• B33Y80/00

  Products made by additive manufacturing · CPC title

• B29C70/58

  comprising fillers only {, e.g. particles, powder, beads, flakes, spheres (B29C70/025 takes precedence, agglomerating hollow spheres to produce synthetic foam B29C70/66; compounding ingredients per se C08K)} · CPC title

• B33Y30/00

  Apparatus for additive manufacturing; Details thereof or accessories therefor · CPC title