Apparatuses for additively manufacturing three-dimensional objects

1. An apparatus for additively manufacturing a three-dimensional object, comprising:

a radiation source;

a carrier on which the three-dimensional object is made;

an applicator assembly configured to apply a polymerizable liquid, said applicator assembly comprising:

a polymerizable liquid supply chamber;

an application roller; and

a metering roller;

a frame, with said applicator assembly and said radiation source connected to said frame, and with said frame defining a build region between said applicator assembly and said carrier;

a first drive assembly interconnecting said applicator assembly and said frame; and

a second drive assembly interconnecting said carrier and said frame,

wherein said applicator assembly further comprises a metering element between the application roller and the metering roller, and

wherein said metering element is a center bar between the application roller and the metering roller.

2. The apparatus of claim 1 , wherein said applicator assembly further comprises a post-metering roller.

3. The apparatus of claim 1 , wherein said application roller and said metering roller both rotate in a counter-clockwise direction.

4. The apparatus of claim 1 , wherein said application roller rotates in a clockwise direction and said metering roller rotates in a counter-clockwise direction.

5. The apparatus of claim 2 , wherein said post-metering roller rotates in a clockwise direction.

6. The apparatus of claim 1 , wherein said metering roller rotates such that its tangential velocity is in an opposite direction of the motion of said carrier.

7. The apparatus of claim 1 , wherein said applicator assembly further comprises a first blade pressed against the metering roller.

8. The apparatus of claim 2 , wherein said applicator assembly further comprises a second blade on top of said post-metering roller.

9. An apparatus for additively manufacturing a three-dimensional object, comprising:

a radiation source;

a carrier on which the three-dimensional object is made;

a first and a second applicator assembly configured to apply a polymerizable liquid, each applicator assembly comprising:

a polymerizable liquid supply chamber;

an application roller; and

a metering roller;

a frame, with said first and applicator assemblies and said radiation source connected to said frame, and with said frame defining a build region between said first and second applicator assembly and said carrier; and

a first drive assembly interconnecting said first and second applicator assemblies and said frame; and

a second drive assembly interconnecting said carrier and said frame,

wherein said first and second applicator assemblies further comprise a metering element between the application roller and the metering roller, and

wherein said metering element is a center bar between the application roller and the metering roller.

10. The apparatus of claim 9 , wherein said first and second applicator assemblies further comprise a post-metering roller.

11. The apparatus of claim 9 , wherein said metering element is a cleaning blade.

12. The apparatus of any one of claim 9 , wherein said application roller and said metering roller of each of said first and second applicator assemblies both rotate in a counter-clockwise direction.

13. The apparatus of claim 9 , wherein said application roller of each of said first and second applicator assemblies rotates in a clockwise direction and said metering roller of each of said first and second applicator assemblies rotates in a counter-clockwise direction.

14. The apparatus of claim 10 , wherein said post-metering roller of each of said first and second applicator assemblies rotates in a clockwise direction.

15. The apparatus of claim 9 , wherein said metering roller of each of said first and second applicator assemblies rotates such that its tangential velocity is in an opposite direction of the motion of said carrier.

16. The apparatus of claim 9 , wherein said first and second applicator assemblies further comprise a first blade pressed against the metering roller.

17. The apparatus of claim 10 , wherein said first and second applicator assemblies further comprise a second blade on top of said post-metering roller.

18. The apparatus of claim 9 , wherein said apparatus further comprises a plurality of air cylinders configured to raise and lower each of said first and second applicator assemblies such that when one applicator assembly is lowered to apply the polymerizable liquid, the other applicator assembly is raised.

19. An apparatus for additively manufacturing a three-dimensional object, comprising:

a radiation source;

a carrier on which the three-dimensional object is made;

an applicator assembly configured to apply a polymerizable liquid, said applicator assembly comprising:

a polymerizable liquid supply chamber;

an application roller;

a metering roller; and

two metering elements, one metering element located between the supply chamber and the application roller and the other metering element located between the application roller and the metering roller;

a frame, with said applicator assembly and said radiation source connected to said frame, and with said frame defining a build region between said applicator assembly and said carrier;

a first drive assembly interconnecting said applicator assembly and said frame; and

a second drive assembly interconnecting said carrier and said frame.

20. The apparatus of claim 19 , wherein the application roller is configured to rotate in a clockwise direction and counterclockwise direction.

21. The apparatus of claim 19 , wherein the polymerizable liquid is a dental resin.

22. The apparatus of claim 19 , wherein the three-dimensional object is a dental prosthetic.

23. The apparatus of claim 22 , wherein the dental prosthetic is a dental implant, a dental bridge, or a dental crown.