Feeding mechanisms for 3d printers

Abstract

In order to have ensure a proper dosing of a 3D printing system, it is disclosed a feeding mechanism for feeding build material to a surface that comprises: a receptacle to receive build material; and an outlet of the build material having a substantially quadrilateral opening with a first dimension and a second dimension orthogonal to one another; the outlet further comprising a third dimension orthogonal to the first dimension and the second dimension defining the height of the outlet, and the feeding mechanism being to selectively feed build material from to the receptacle through the outlet onto a surface as the feeding mechanism moves along a travel direction over the surface, being such travel direction parallel to the first dimension of the outlet, the feeding mechanism further comprising an actuator to modify the magnitude of at least one of the second dimension or the third dimension outlet.

1 - 15 . (canceled) 
     
     
         16 . A 3D printing system comprising:
 a feeding mechanism for feeding build material to a surface, the feeding mechanism including:
 a receptacle to receive build material; 
 an outlet through which the build material is to be outputted onto the surface as the feeding mechanism moves along a first axis over the surface, the outlet having a quadrangular opening formed by a first end wall and a second end wall; and 
 an actuator to move at least one of the first end wall and the second end wall in at least one of a vertical direction and a horizontal direction to vary a size of the outlet in at least one of the vertical direction and the horizontal direction; and 
   a spreader to move along a second axis to spread the build material from the surface over a build surface.   
     
     
         17 . The 3D printing system of  claim 16 , wherein the actuator is to move at least one of the first end wall and the second end wall along the second axis to vary the size of the outlet in the horizontal direction, wherein the first axis is orthogonal to the second axis. 
     
     
         18 . The 3D printing system of  claim 16 , wherein the actuator is to move at least one of the first end wall and the second end wall along a third axis that is perpendicular to the first axis and the second axis to vary the size of the outlet in the vertical direction. 
     
     
         19 . The 3D printing system of  claim 16 , further comprising:
 a motor coupled to the feeding mechanism, wherein the motor is to cause the feeding mechanism to be moved linearly along the first axis.   
     
     
         20 . The 3D printing system of  claim 16 , wherein the actuator is to move the first end wall and the second end wall in both the vertical and horizontal directions to vary the size of the outlet in both the vertical and horizontal directions. 
     
     
         21 . The 3D printing system of  claim 16 , wherein the actuator is to bi-directionally move the first end wall and the second end wall in both the vertical and horizontal directions to bi-directionally vary the size of the outlet in both the vertical and horizontal directions. 
     
     
         22 . The 3D printing system of  claim 16 , further comprising:
 a carriage to move bi-directionally over the surface along the first axis, wherein the feeding mechanism is mounted to the carriage.   
     
     
         23 . The 3D printing system of  claim 16 , further comprising:
 a carriage to move bi-directionally over the surface along the second axis, wherein the spreader is attached to the carriage.   
     
     
         24 . The 3D printing system of  claim 16 , further comprising:
 the build surface, wherein the build surface is to be lowered after each layer of build material is selectively solidified over the build surface.   
     
     
         25 . A 3D printing system comprising:
 a build surface;   a dosing surface;   a feeding mechanism including:
 a receptacle to receive build material; 
 an outlet having a quadrangular opening, the quadrangular opening being formed by a first end wall and a second end wall, wherein at least one of the first end wall and the second end wall is movable with respect to the other one of the first end wall and the second. end wall; 
 an actuator to move at least one of the first end wall and the second end wall in at least one of a vertical direction and a horizontal direction to vary a size of the outlet in at least one of the vertical direction and the horizontal direction, wherein the feeding mechanism is to deposit build material on the dosing surface through the outlet as the feeding mechanism is moved along a first axis over the dosing surface; and 
   a spreader to move along a second axis to spread the build material from the dosing surface over the build surface, wherein the second axis is orthogonal to the first axis.   
     
     
         6 . The 3D printing system of  claim 25 , wherein the actuator is to move the first end wall and the second end wall bi-directionally along the second axis to vary the size of the outlet in the horizontal direction. 
     
     
         27 . The 3D printing system of  claim 25 , wherein the actuator is to move the first end wall and the second end wall bi-directionally along a third axis that is perpendicular to the first axis and the second axis to vary the size of the outlet in the vertical direction. 
     
     
         28 . The 3D printing system of  claim 27 , wherein the actuator is to move the first end wall and the second end wall bi-directionally along both the second axis and the third axis to vary the size of the outlet in both the vertical direction and the horizontal direction. 
     
     
         29 . The 3D printing system of  claim 25 , further comprising:
 a first carriage to move bi-directionally along the second axis, wherein the spreader is attached to the first carriage.   
     
     
         30 . The 3D printing system of  claim 25 , further comprising:
 a second carriage to move bi-directionally along the first axis, wherein the feeding mechanism is attached to the second carriage.