Methods and apparatus for additive manufacturing of glass

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.

What is claimed is: 
     
         1 . A method comprising, in combination:
 (a) heating of glass material 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 at least part of the deposition
 (i) the object being formed rests on a build platform, 
 (ii) the molten glass material is deposited layer-by-layer; and 
 (iii) one or more computers control where in each layer the molten glass material is deposited, by controlling a set of actuators that actuate movement of one or both of the nozzle and build platform. 
   
     
     
         2 . The method of  claim 1 , wherein at least one actuator, out of the set of actuators, directly or indirectly actuates the nozzle to move along at least one horizontal axis. 
     
     
         3 . The method of  claim 1 , wherein:
 (a) the heating occurs in a kiln;   (b) during the deposition, a first actuator, out of the set of actuators, actuates the kiln and the nozzle to move along a first horizontal axis; and   (c) during the deposition, 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.   
     
     
         4 . The method of  claim 1 , wherein, during the deposition:
 (a) a first actuator, out of the set of actuators, actuates the nozzle to move along a horizontal axis; and   (b) a second actuator, out of the set of actuators, actuates the build platform to rotate.   
     
     
         5 . 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.   
     
     
         6 . 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 mechanical force. 
     
     
         7 . The method of  claim 5 , wherein, during the deposition:
 (a) the nozzle is stationary relative to a wall of the annealing kiln; and   (b) at least one actuator, out of the set of actuators, actuates the build platform to cause the build platform to move relative to the nozzle and the wall.   
     
     
         8 . The method of  claim 1 , wherein:
 (a) an exit portion of the nozzle surrounds or is adjacent to an exit orifice of the nozzle;   (b) the method further comprises cooling the exit portion of the nozzle by causing fluid to flow through a region that adjoins the exit portion; and   (c) the fluid is cooler than molten glass material exiting the exit orifice.   
     
     
         9 . Apparatus comprising, in combination:
 (a) a build platform;   (b) one or more heating elements for heating of glass material, such that the glass material becomes or remains molten;   (c) a nozzle for deposition of the molten glass material, such that the molten glass material is extruded through the nozzle to form an object that rests on the build platform;   (d) a set of actuators; and   (e) one or more computers for controlling the deposition, such that, during at least a portion of the deposition
 (i) the molten glass material is deposited layer-by-layer; and 
 (ii) the one or more computers control where in each layer the molten glass material is deposited, by causing the set of actuators to actuate movement of one or both of the nozzle and build platform. 
   
     
     
         10 . The apparatus of  claim 9 , wherein at least one actuator, out of the set of actuators, is configured to actuate the nozzle to move along at least one horizontal axis. 
     
     
         11 . The apparatus of  claim 9 , wherein:
 (a) a first actuator, out of the set of actuators, is configured to actuate the nozzle and at least some of the heating elements to move parallel to a first horizontal axis; and   (b) a second actuator, out of the set of actuators, is configured to actuate the nozzle and at least some of the heating elements to move parallel to a second horizontal axis, the first and second horizontal axes being perpendicular to each other.   
     
     
         12 . The apparatus of  claim 9 , wherein:
 (a) a first actuator, out of the set of actuators, is configured to actuate the nozzle to move parallel to a horizontal axis; and   (b) a second actuator, out of the set of actuators, is configured to actuate the build platform to rotate.   
     
     
         13 . The apparatus of  claim 9 , wherein:
 (a) the build platform is positioned inside a kiln; and   (b) the kiln is configured to anneal extruded glass material.   
     
     
         14 . The apparatus of  claim 9 , wherein the apparatus includes a valve for controlling flow of molten glass material through the nozzle. 
     
     
         15 . The apparatus of  claim 13 , wherein:
 (a) the nozzle is stationary relative to a wall of the kiln; and   (b) at least one actuator, out of the set of actuators, is configured to actuate the build platform such that the build platform moves relative to the nozzle and the wall.   
     
     
         16 . The apparatus of  claim 9 , wherein:
 (a) an exit portion of the nozzle surrounds or is adjacent to an exit orifice of the nozzle; and   (b) the apparatus further comprises one or more tubes or cavities adjacent to the exit portion, which tubes or cavities are configured to cool the exit portion when fluid cooler than the molten glass material flows through the tubes or cavities.   
     
     
         17 . Apparatus comprising:
 (a) heating elements for heating glass material, such that the glass material becomes or remains molten;   (b) a nozzle for extruding the molten glass material;   (c) tubes or chambers that are adjacent to a tip of the nozzle;   (d) a pump for pumping fluid through the tubes or chamber to cool the tip of the nozzle to a temperature that is less than temperature of the molten glass material;   (e) a set of actuators; and   (f) a set of computers that is programmed to control the set of actuators such that the set of actuators actuate movement of one or both of the nozzle and build platform during the extruding, such that extruded molten glass material forms an object in accordance with digital instructions accessed or generated by at least one computer, out of the set of computers.   
     
     
         18 . The apparatus of  claim 17 , further comprising a kiln for annealing the molten glass material. 
     
     
         19 . The apparatus of  claim 17 , wherein:
 (a) a first actuator, out of the set of actuators, is configured to actuate the nozzle and at least some of the heating elements to move parallel to a first horizontal axis; and   (b) a second actuator, out of the set of actuators, is configured to actuate the nozzle and at least some of the heating elements to move parallel to a second horizontal axis, the first and second horizontal axes being perpendicular to each other.   
     
     
         20 . The apparatus of  claim 17 , wherein:
 (a) a first actuator, out of the set of actuators, is configured to actuate the nozzle to move parallel to a horizontal axis; and   (b) a second actuator, out of the set of actuators, is configured to actuate the build platform to rotate.