Additive manufacturing method for discharging interlocking continuous reinforcement

Abstract

An additive manufacturing method is disclosed. The method may include directing into a print head a reinforcement having a continuous axial core and integral branches extending radially outward from the continuous axial core. The method may also include coating the reinforcement in a matrix, and softening a portion of a track of the coated reinforcement that was previously discharged from the print head. The method may further include discharging from the print head a track of the coated reinforcement adjacent the previously discharged track of the coated reinforcement, such that cross-bonding of the integral branches occurs between the discharging track of the coated reinforcement and the softened portion of the previously discharged track of the coated reinforcement.

What is claimed is: 
     
         1 . A system for additively manufacturing a composite structure, comprising:
 a support moveable in multiple dimensions; and   a print head moveable by the support during discharge of a material that forms the composite structure, the print head having an inner dimension less than a corresponding outer dimension of the material after the material is discharged.   
     
     
         2 . The system of  claim 1 , wherein the outer dimension of the material includes a dimension at a cross-section of the material. 
     
     
         3 . The system of  claim 1 , wherein the print head includes a chamber configured to wet a continuous reinforcements with a matrix to form the material. 
     
     
         4 . The system of  claim 1 , further including a first device configured to at least soften the material at a first side of the print head. 
     
     
         5 . The system of  claim 4 , further including a compactor configured to press the material against a previously discharged track of the material. 
     
     
         6 . The system of  claim 5 , wherein the compactor is located at a side of the print head opposite the first device. 
     
     
         7 . The system of  claim 4 , further including a second device configured to harden the material at a second side of the print head opposite the first side. 
     
     
         8 . The system of  claim 7 , further including a compactor configured to press the material against a previously discharged track of the material. 
     
     
         9 . The system of  claim 8 , wherein the compactor is located between a discharge outlet of the print head and the second device. 
     
     
         10 . The system of  claim 7 , wherein at least one of the first and second devices are configured to expose the material to light. 
     
     
         11 . The system of  claim 10 , wherein both of the first and second devices are configured to expose the material to light. 
     
     
         12 . The system of  claim 7 , wherein:
 the first side is a leading side relative to motion of the print head imparted by the support; and   the second side is a trailing side relative to the motion of the print head imparted by the support.   
     
     
         13 . The system of  claim 1 , wherein:
 the inner dimension is an inner nozzle diameter; and   the outer dimension is an outer diameter of the material.   
     
     
         14 . A system for additively manufacturing a composite structure, comprising:
 a support moveable in multiple dimensions; and   a print head moveable by the support during discharge of a material that forms the composite structure, the print head having a discharge outlet with a size that is less than a corresponding size of the material after the material passes through the discharge outlet.   
     
     
         15 . A system for additively manufacturing a composite structure, comprising:
 a support moveable in multiple dimensions;   an outlet moveable by the support during discharge of a material that forms the composite structure;   a first device configured to at least soften the material at a first side of the outlet; and   a second device configured to harden the material at a second side of the outlet opposite the first side.   
     
     
         16 . The system of  claim 15 , further including a compactor configured to press the material against a previously discharged track of the material. 
     
     
         17 . The system of  claim 16 , wherein the compactor is located at the second side of the outlet. 
     
     
         18 . The system of  claim 17 , wherein the compactor is located between the outlet and the second device. 
     
     
         19 . The system of  claim 15 , wherein at least one of the first and second devices are configured to expose the material to light. 
     
     
         20 . The system of  claim 15 , wherein:
 the first side is a leading side relative to motion of the outlet imparted by the support; and   the second side is a trailing side relative to the motion of the outlet imparted by the support.