Apparatus and Methods for 3D Printing

Abstract

The invention relates to apparatus and methods for producing three-dimensional objects and auxiliary systems used in conjunction with the aforementioned apparatus and methods. The apparatus and methods involve continuously printing radially about a circular and/or rotating build table using multiple printheads. The apparatus and methods also include optionally using multiple build tables. The auxiliary systems relate to build material supply, printhead cleaning, diagnostics, and monitoring operation of the apparatus.

1 - 26 . (canceled)  
   
   
       27 . A method of fabricating a three-dimensional object comprising the steps of: 
 depositing successive layers of a build material on a rotary build table; and    depositing a liquid in a predetermined pattern on each successive layer of the build material to form the three-dimensional object.    
   
   
       28 . The method of  claim 27  further comprising the step of rotating the build table continuously.  
   
   
       29 . The method of  claim 27 , wherein the step of depositing successive layers of a build material on a rotary build table includes distributing the build material over at least a portion of the build table with a spreader.  
   
   
       30 . The method of  claim 27  further comprising the step of measuring an amount of excess build material deposited on the rotary build table.  
   
   
       31 . The method of  claim 30  further comprising the step of adjusting the amount of build material deposited on the rotary build table based on the amount of excess build material measured.  
   
   
       32 . The method of  claim 27 , wherein the step of depositing a liquid is performed by an array of at least one printhead.  
   
   
       33 . The method of  claim 32 , wherein the array is configured to dispense fluid at substantially any radial location of the rotary build table without adjustment.  
   
   
       34 . The method of  claim 32 , wherein the array prints an entire surface of the build table by continuous consecutive radial scanning motions.  
   
   
       35 . The method of  claim 32 , wherein the array of printheads can be adjusted incrementally radially relative to the rotary build table.  
   
   
       36 - 42 . (canceled)  
   
   
       43 . An apparatus for cleaning a printhead used in a three-dimensional printer, the apparatus comprising: 
 a base;    a cam track disposed within the base;    a cap carrier slidably engaged with the cam track; and    a sealing cap defining a cavity and disposed on the carrier, the cap being transportable into engagement with a face of the printhead by the carrier.    
   
   
       44 . The apparatus of  claim 43  further comprising: 
 a cleaning fluid source in communication with the cap for cleaning the printhead face; and    a vacuum source in communication with the cap for removing used wash fluid and debris.    
   
   
       45 . The apparatus of  claim 44 , wherein the vacuum source creates a negative pressure within the cavity, the negative pressure preventing the wash fluid from entering a jet nozzle and drawing at least one of a binder fluid and debris from the jet nozzle.  
   
   
       46 . The apparatus of  claim 43  further comprising a spring coupled to the carrier and the base to bias the carrier into a receiving position for receiving the printhead.  
   
   
       47 . The apparatus of  claim 46 , wherein the carrier includes a stop disposed on a distal end of the carrier for engaging the printhead as the printhead enters the apparatus and the printhead slides the carrier rearward along the cam track after engaging the stop until the printhead face and cap sealably engage.  
   
   
       48 . The apparatus of  claim 47  further comprising a latch pawl coupled to the base for engaging with the carrier to prevent forward movement of the carrier.  
   
   
       49 . The apparatus of  claim 48  further comprising a squeegee disposed on a proximal end of the carrier, the squeegee positioned to engage the printhead face as the printhead exits the apparatus.  
   
   
       50 . A method of cleaning a printhead used in a three-dimensional printer comprising the steps of: 
 receiving the printhead within an apparatus comprising: 
 a base;  
 a cam track disposed within the base;  
 a cap carrier slidably engaged with the cam track; and  
 a sealing cap defining a cavity and disposed on the carrier;  
   engaging a face of the printhead with the cap;    drawing a vacuum on the cavity; and    introducing a cleaning fluid into the cavity and into contact with the printhead face.    
   
   
       51 . The method of  claim 50  further comprising the step of removing the cleaning fluid from the cavity.  
   
   
       52 . The method of  claim 51  further comprising the steps of: 
 disengaging the cap from the printhead face; and    wiping the printhead face with a squeegee as the printhead is withdrawn from the apparatus.    
   
   
       53 . The method of  claim 50 , wherein the vacuum source creates a negative pressure within the cavity, the negative pressure preventing the wash fluid from entering a jet nozzle and drawing at least one of a binder fluid and debris from the jet nozzle.