Layer transfusion with heat capacitor belt for additive manufacturing

Abstract

An additive manufacturing system comprising a transfer medium configured to receive the layers from a imaging engine, a heater configured to heat the layers on the transfer medium, and a layer transfusion assembly that includes a build platform, and is configured to transfuse the heated layers onto the build platform in a layer-by-layer manner to print a three-dimensional part.

1 . An additive manufacturing system for printing a three-dimensional part, the additive manufacturing system comprising:
 an imaging engine configured to develop an imaged layer;   a movable build platform;   a rotatable belt configured to receive the imaged layer from the imaging engine, wherein the rotatable belt has an average thermal inertia of at least about 400 joules/(meter 2 -Kelvin-second 0.5 );   a first heater configured to heat the rotatable belt and the imaged layer on the rotatable belt;   a nip roller configured to press the heated imaged layer conveyed by the rotatable belt onto a top layer of the three-dimensional part retained by the movable build platform; and   a release roller configured to separate the pressed imaged layer from the heated rotatable belt such that the pressed imaged layer remains adhered as a new top layer of the three-dimensional part;   wherein the rotatable belt is configured to thermally conduct heat into the three-dimensional part while the pressed imaged layer moves between the nip roller and the release roller.   
     
     
         2 . The additive manufacturing system of  claim 1 , wherein the first heater comprises a non-contact radiant heater. 
     
     
         3 . The additive manufacturing system of  claim 1 , and further comprising a second heater configured to post-heat the three-dimensional part having the new top layer. 
     
     
         4 . The additive manufacturing system of  claim 1 , wherein the nip roller is configured to be heated. 
     
     
         5 . The additive manufacturing system of  claim 1 , wherein the moveable build platform is configured to move in a reciprocating rectangular pattern that is synchronized with a rotation of the rotatable belt. 
     
     
         6 . The additive manufacturing system of  claim 1 , and further comprising a cooling unit configured to cool the three-dimensional part having the new top layer. 
     
     
         7 . The additive manufacturing system of  claim 6 , wherein the cooling unit comprises a belt configured to be cooled down and to contact the new top layer of the three-dimensional part to conductively draw heat from the three-dimensional part. 
     
     
         8 . The additive manufacturing system of  claim 1 , wherein the rotatable belt comprises a multiple-layer belt. 
     
     
         9 . The additive manufacturing system of  claim 1 , wherein thermoplastic-based powder comprises an acrylonitrile-butadiene-styrene copolymer, and wherein the wherein the first heater is configured to heat the rotatable belt and the imaged layer on the rotatable belt to a temperature ranging from about 180° C. to about 220° C. 
     
     
         10 . A method for printing a three-dimensional part with an additive manufacturing system, the method comprising:
 imaging a layer of the three-dimensional part;   transferring the imaged layer to a rotatable belt having an average thermal inertia of at least about 400 joules/(meter 2 -Kelvin-second 0.5 )   heating the rotatable belt and the imaged layer while the imaged layer is retained on the rotating belt;   pressing the heated imaged layer between the heated rotatable belt and a top surface of the three-dimensional part so that the heated imaged layer fuses to the top surface of the three-dimensional part;   maintaining contact between the rotatable belt and the fused imaged layer so as to conduct thermal energy from the heated rotatable belt to the three-dimensional part; and   releasing the pressed layer from the rotatable belt such that the pressed layer defines a new top surface of the three-dimensional part.   
     
     
         11 . The method of  claim 10 , wherein imaging the layer comprises developing the layer with an electrophotography engine. 
     
     
         12 . The method of  claim 10 , wherein pressing the heated layer between the rotatable belt and the top surface of the three-dimensional part comprises engaging the rotatable belt with a nip roller. 
     
     
         13 . The method of  claim 10 , and further comprising cooling the three-dimensional part having the new top layer. 
     
     
         14 . The method of  claim 13 , wherein cooling the three-dimensional part comprises drawing thermal energy from the three-dimensional part having the new top layer by thermal conduction. 
     
     
         15 . The method of  claim 14 , wherein cooling by thermal conduction comprises contacting the new top layer with a cooling belt. 
     
     
         16 . A method for printing a three-dimensional part with an additive manufacturing system, the method comprising:
 imaging a layer of the three-dimensional part;   rotating a belt having an average thermal inertia of at least about 400 joules/(meter 2 -Kelvin-second 0.5 );   transferring the imaged layer to the rotating belt;   heating the rotating belt and the imaged layer while the imaged layer is retained on the rotating belt;   engaging the heated rotatable belt with a nip roller, which presses the heated layer to a top surface of the three-dimensional part;   moving the three-dimensional part in a direction and at a rate that is synchronized with a rotation of the belt;   conducting thermal energy from the rotating belt to the three-dimensional part while moving the three-dimensional part in the synchronized direction and rate; and   releasing the pressed layer from the rotatable belt such that the pressed layer defines a new top surface of the three-dimensional part.   
     
     
         17 . The method of  claim 16 , wherein imaging the layer comprises developing the layer with an electrophotography engine. 
     
     
         18 . The method of  claim 16 , and further comprising cooling the three-dimensional part having the new top layer. 
     
     
         19 . The method of  claim 18 , wherein cooling the three-dimensional part comprises drawing thermal energy from the three-dimensional part having the new top layer by thermal conduction. 
     
     
         20 . The method of  claim 16 , heating the rotating belt and the imaged layer comprises heating the rotating belt and the imaged layer to a temperature ranging from about 180° C. to about 220° C.