Methods and apparatus for additive manufacturing of glass

Patent metadata

Field	Value
Publication number	US-2017081236-A1
Application number	US-201615365577-A
Country	US
Kind code	A1
Filing date	Nov 30, 2016
Priority date	Apr 25, 2014
Publication date	Mar 23, 2017
Grant date	—

Abstract

In illustrative implementations of this invention, a crucible kiln heats glass such that the glass becomes or remains molten. A nozzle extrudes the molten glass while one or more actuators actuate movements of the nozzle, a build platform or both. A computer controls these movements such that the extruded molten glass is selectively deposited to form a 3D glass object. The selective deposition of molten glass occurs inside an annealing kiln. The annealing kiln anneals the glass after it is extruded. In some cases, the actuators actuate the crucible kiln and nozzle to move in horizontal x, y directions and actuate the build platform to move in a z-direction. In some cases, fluid flows through a cavity or tubes adjacent to the nozzle tip, in order to cool the nozzle tip and thereby reduce the amount of glass that sticks to the nozzle tip.

First claim

What is claimed is:

1 . A method comprising, in combination:
(a) heating of glass material in a kiln such that the glass material becomes or remains molten; and (b) deposition of the molten glass material, in which the molten glass material is extruded through a nozzle to form an object; wherein during the deposition
(i) the object being formed rests on a build platform,
(ii) the molten glass material is deposited layer-by-layer, and
(iii) a set of actuators causes
(A) the kiln and the nozzle to move horizontally, and
(B) the build platform to move vertically.

2 . The method of claim 1 , wherein:
(i) a first actuator, out of the set of actuators, actuates the kiln and the nozzle to move along a first horizontal axis, and (ii) a second actuator, out of the set of actuators, actuates the kiln and the nozzle to move along a second horizontal axis, the first and second horizontal axes being perpendicular to each other, and (iii) a third actuator, out of the set of actuators, actuates the build platform to move along a vertical axis.

3 . The method of claim 1 , wherein:
(i) a first actuator, out of the set of actuators, actuates the kiln and the nozzle to move along a horizontal axis, and (ii) a second actuator, out of the set of actuators, actuates the build platform to rotate, and (iii) a third actuator, out of the set of actuators, actuates the build platform to move along a vertical axis.

4 . The method of 1 , wherein:
(a) during the deposition, the build platform is positioned inside an annealing kiln; and (b) after the deposition, the annealing kiln anneals extruded glass material.

5 . The method of claim 1 , wherein extrusion of the molten glass material through the nozzle is actuated by gravitational force and is not actuated by any other net force.

6 . The method of claim 1 , wherein:
(a) a region of the nozzle surrounds or is adjacent to an exit orifice of the nozzle; (b) the method further comprises cooling the region by causing fluid to flow through the region; and (c) the fluid is cooler than molten glass material exiting the exit orifice.

7 . The method of claim 6 , wherein an effect of the cooling is that less glass material sticks to a tip of the nozzle than would stick to the nozzle in the absence of the cooling.

8 . The method of claim 1 , wherein:
(a) tubes or cavities surround or are adjacent to an exit orifice of the nozzle; (b) the method further comprises cooling the region by causing fluid to flow through the tubes or cavities; and (c) the fluid is cooler than molten glass material exiting the exit orifice.

9 . The method of claim 8 , wherein an effect of the cooling is that less glass material sticks to a tip of the nozzle than would stick to the nozzle in the absence of the cooling.

10 . The method of claim 1 , further comprising a valve controlling flow of molten glass material through the nozzle.

11 . The method of claim 10 , wherein:
(a) the valve comprises a pair of shears; and (b) closing the shears
(i) cuts a filament of the molten glass material that is exiting the nozzle, and
(ii) blocks the flow.

12 . The method of claim 10 , wherein:
(a) the valve comprises a rod; and (b) the rod stops the flow when the rod is moved into the nozzle and touches interior walls of the nozzle.

13 . The method of claim 1 , further comprising a plunger:
(a) exerting pressure on the molten glass material; and (b) thereby pushing the molten glass material through the nozzle.

14 . The method of claim 1 , further comprising air:
(a) exerting pressure on the molten glass material; and (b) thereby pushing the molten glass material through the nozzle.

15 . The method of claim 1 , further comprising blowing air through a tube, such that:
(a) a column of air infiltrates a filament of the molten glass material as the filament is extruded through the nozzle; and (b) the column of air is trapped inside the filament and is co-axial with the filament.

16 . The method of claim 1 , wherein the object that is formed is optically transparent.

Assignees

• Massachusetts Inst Technology

Inventors

• Klein John
• Franchin Giorgia
• Stern Michael
• Kayser Markus
• Inamura Chikara
• Dave Shreya
• Oxman Neri
• Houk Peter

Classifications

• C03B17/04

  Forming tubes or rods by drawing from stationary or rotating tools or from forming nozzles · CPC title

• C03B5/0336

  Shaft furnaces (C03B5/0338 takes precedence) · CPC title

• C03B25/02 Primary

  in a discontinuous way · CPC title

• C03B7/098

  electric · CPC title

• B33Y30/00

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