System for additively manufacturing composite structure

Abstract

A system for additively manufacturing a composite structure is disclosed. The system may include a support, and a print head operatively connected to and moveable by the support. The print head may be configured to discharge a continuous reinforcement that is at least partially coated in a liquid matrix. The system may also include a cure enhancer connected to the print head and configured to expose the discharge to cure energy to cause the, and a controller in communication with the heater and the cure enhancer. The controller may be configured to selectively activate the heater and the cure enhancer.

What is claimed is: 
     
         1 . An additive manufacturing system, comprising:
 a support;   a print head operatively connected to and moveable by the support, the print head configured to discharge a continuous reinforcement that is at least partially coated in a liquid matrix;   a cure enhancer connected to the print head and configured to expose the discharge to cure energy to cause the liquid matrix to at least partially polymerize;   a heater configured to warm the liquid matrix inside of the print head; and   a controller in communication with the heater and the cure enhancer, the controller being configured to selectively activate the heater and the cure enhancer.   
     
     
         2 . The additive manufacturing system of  claim 1 , wherein the controller is configured to selectively activate at least one of the heater and the cure enhancer based on a desired glass transition temperature of the liquid matrix within a fabricated structure. 
     
     
         3 . The additive manufacturing system of  claim 2 , further including a sensor configured to generate a signal indicative of a temperature of the liquid matrix inside of the print head, wherein the controller is configured to activate the at least one of the heater and the cure enhancer based on the signal. 
     
     
         4 . The additive manufacturing system of  claim 1 , further including an insulating jacket associated with the print head to reduce heat loss from the liquid matrix. 
     
     
         5 . The additive manufacturing system of  claim 3 , wherein the controller is configured to cause the print head to discharge material only when the signal indicates an internal temperature of the liquid matrix within a desired range. 
     
     
         6 . A method of additively manufacturing a composite structure, comprising:
 receiving a liquid matrix into a print head;   receiving a continuous reinforcement into the print head;   at least partially coating the continuous reinforcement with the liquid matrix inside of the print head; and   selectively discharging the continuous reinforcement and the liquid matrix only when a temperature of the liquid matrix is within a desired range.   
     
     
         7 . The method of  claim 6 , further including generating a signal indicative of the temperature of the liquid matrix, wherein selectively discharging the continuous reinforcement and the liquid matrix includes selectively discharging the continuous reinforcement and the liquid matrix only when the signal indicates that the temperature of the liquid matrix is within the desired range. 
     
     
         8 . The method of  claim 6 , further including selectively conditioning the liquid matrix when the temperature of the liquid matrix is outside of the desired range. 
     
     
         9 . The method of  claim 8 , wherein selectively conditioning includes heating the liquid matrix inside of the print head. 
     
     
         10 . The method of  claim 9 , further including exposing the liquid matrix to a cure energy after discharge from the print head. 
     
     
         11 . The method of  claim 10 , wherein selectively conditioning further includes adjusting an amount of energy directed to the liquid matrix after discharge from the print head. 
     
     
         12 . The method of  claim 9 , wherein heating the liquid matrix includes heating the liquid matrix to about 80-95% of a kickoff temperature of the liquid matrix. 
     
     
         13 . The method of  claim 9 , wherein heating the liquid matrix inside of the print head increases a glass transition temperature of the composite structure. 
     
     
         14 . The method of  claim 6 , wherein the desired range is specific to the liquid matrix. 
     
     
         15 . A method of additively manufacturing a composite structure, comprising:
 receiving a liquid matrix into a print head;   receiving a continuous reinforcement into the print head;   at least partially coating the continuous reinforcement with the liquid matrix inside of the print head;   monitoring a temperature of the liquid matrix inside of the print head;   responsively adjusting the temperature of the liquid matrix;   selectively discharging the continuous reinforcement and the liquid matrix when a temperature of the liquid matrix is within a desired range; and   exposing the liquid matrix to a cure energy after discharge.   
     
     
         16 . The method of  claim 15 , further including generating a signal indicative of the temperature of the liquid matrix, wherein selectively discharging the continuous reinforcement and the liquid matrix includes selectively discharging the continuous reinforcement and the liquid matrix only when the signal indicates that the temperature of the liquid matrix is within the desired range. 
     
     
         17 . The method of  claim 15 , wherein selectively conditioning includes heating the liquid matrix inside of the print head. 
     
     
         18 . The method of  claim 17 , wherein selectively conditioning further includes adjusting the exposing of the liquid matrix to energy after discharge from the print head. 
     
     
         19 . The method of  claim 18 , wherein heating the liquid matrix includes heating the liquid matrix to 80-95% of a kickoff temperature of the liquid matrix. 
     
     
         20 . The method of  claim 19 , wherein heating the liquid matrix inside of the print head increases a glass transition temperature of the composite structure.