Method and apparatus for printing a retaining wall in the manufacture of three-dimensional objects

Patent metadata

Field	Value
Publication number	US-2025065562-A1
Application number	US-202418792640-A
Country	US
Kind code	A1
Filing date	Aug 2, 2024
Priority date	Aug 4, 2023
Publication date	Feb 27, 2025
Grant date	—

Abstract

Methods and apparatuses for making three-dimensional objects from a bindable powder are shown and described. A three-dimensional retaining wall is printed into the bindable powder to enclose the three-dimensional object and a volume of unsolidified bindable powder surrounding the three-dimensional object. In order to provide a more stable printed retaining wall, the wall is printed at less than one hundred percent image saturation and/or less than one hundred percent voxel saturation to increase the speed of solidification. One-hundred percent image saturation refers to solidifying all of the voxels (or pixels) that overlap the printed three-dimensional retaining wall, and one-hundred percent voxel saturation refers to an amount of binder per voxel that is printed to form the three-dimensional object that the printed three-dimensional retaining wall wholly or partially encloses.

First claim

What is claimed is:

1 . An apparatus for making a three-dimensional object along a build axis, comprising:
a powder dispenser operable to dispense powder within a dispensing plane to define a print plane while moving over the dispensing plane; at least one printhead operable to print a liquid binder onto the powder within the print plane while moving over the print plane; a receiving surface comprising an object build area; an extendable first retaining barrier that at least partially encloses the object build area, wherein the extendable first retaining barrier has a top surface that is extendable along the build axis away from the receiving surface; an actuator operable to extend the extendable first retaining barrier to a plurality of positions along the build axis; and a controller programmed to (i) receive second retaining barrier data comprising a plurality of print data sets, wherein each print data set corresponds to a position along the build axis and defines locations in the print plane where the second retaining barrier is to be formed, the locations in the print plane where the second retaining barrier is to be formed defining inner and outer boundaries of the second retaining barrier and a total second retaining barrier area in the print plane, and (ii) cause the at least one printhead to print the liquid binder onto the powder in the print plane and between the inner and outer boundaries over a reduced second retaining barrier area in the print plane which is less than the total second retaining barrier area.

2 . The apparatus of claim 1 , wherein the reduced second retaining barrier area is no less than 40 percent of the total area.

3 . An apparatus according to claim 1 , wherein the reduced second retaining barrier area is no greater than 70 percent of the total second retaining barrier area.

4 . The apparatus of claim 1 , wherein each print data set comprises a set of pixels, each set of pixels at each build axis position occupies the total second retaining barrier area in the print plane, each pixel in each set of pixels corresponds to a location in the print plane at which the second retaining barrier is to be formed, and wherein the controller is programmed to cause the at least one printhead to print liquid binder onto the powder for a set of fewer than all of the pixels in each set of pixels.

5 . The apparatus of claim 1 , wherein each print data set comprises a set of voxels, each set of voxels at each build axis position occupies the total second retaining barrier area in the print plane, each voxel in each set of voxels corresponds to a location in the print plane at which the second retaining barrier is to be formed, and wherein the controller is programmed to cause the at least one printhead to print liquid binder onto the powder for a set of fewer than all of the voxels in each set of voxels.

6 . The apparatus of claim 4 , wherein the set of fewer than all of the pixels is no more than 40 percent of all the pixels in each set of pixels.

7 . An apparatus according to claim 4 , wherein the set of fewer than all of the pixels is no greater than 70 percent of all of the pixels in each set of pixels.

8 . An apparatus according to claim 5 , wherein the set of fewer than all of the voxels is no more than 40 percent of all the voxels.

9 . An apparatus according to claim 5 , wherein the set of fewer than all of the voxels is no more than 70 percent of all of the voxels.

10 . The apparatus of claim 1 , wherein the controller is programmed to print the liquid binder onto the powder at locations in the print plane at which the three-dimensional object is to be formed at a first percentage of binder liquid volume per unit volume of the powder and is further programmed to print the liquid binder onto the powder the locations in the print plane at which the second retaining barrier is to be formed at a second percentage of binder liquid per unit volume of the powder, and the second percentage is les than the first percentage per unit volume of the powder.

11 . The apparatus of claim 10 , wherein the unit volume of the powder is a voxel volume ranging from about 0.4×10 −5 cm 3 to about 6.3×10 −5 cm 3 .

12 . The apparatus of claim 11 , wherein the first percentage of binder liquid volume per voxel volume is from about one to about 1.5 percent.

13 . An apparatus according to claim 11 , wherein the second percentage of binder liquid per voxel volume is less than one percent.

14 . An apparatus according to claim 1 , wherein at one or more build (z) axis locations the secondary retaining barrier has a reduced thickness extending along one selected from the travel axis and the print axis.

15 . The apparatus of claim 1 , wherein the primary retaining barrier does not comprise the powder.

16 . The apparatus of claim 1 , wherein the extendable first retaining barrier surrounds the object build area.

17 . The apparatus of claim 1 , wherein the extendable first retaining barrier comprises a set of hinged panels.

18 . The apparatus of claim 1 , wherein the extendable first retaining barrier comprises a plurality of rigid, nested sleeves or panels that define a telescoping fence.

19 . An apparatus for making a three-dimensional object, comprising:
a powder dispenser operable to dispense powder within a dispensing plane to define a print plane while moving over the dispensing plane, wherein the powder dispenser is also movable along a build axis perpendicular to the dispensing plane; at least one printhead operable to print a liquid binder onto the powder within the print plane while moving over the print plane, wherein the printhead is movable along the build axis; a receiving surface defining an object build area; an extendable first retaining barrier that at least partially encloses an object build area in a direction parallel to the dispensing plane, wherein the extendable first retaining barrier has a top surface that is extendable along the build axis away from the receiving surface; an actuator operable to extend the extendable first retaining barrier to a plurality of positions along the build axis; and a controller programmed to (i) receive a plurality of three-dimensional object voxel data sets, wherein each three-dimensional object voxel data set comprises a plurality of three-dimensional object voxels and corresponds to a location in the print plane and along the build axis where the three-dimensional object is to be formed, (ii) print a first volume of binder per voxel into the powder at each three-dimensional object voxel; and (iii) receive a plurality of second retaining barrier data sets, wherein each second retaining barrier data set comprises a plurality of second retaining barrier voxels and corresponds to a location in the print plane and along the build axis where the second retaining barrier is to be formed, and (iv) cause the at least one printhead to print a second volume of liquid binder per voxel into the powder at at least some of the second retaining barrier voxels at a second volume of binder per voxel, wherein the second volume of binder per voxel is less than the first volume of binder per voxel.

20 . The apparatus of claim 19 , wherein the second volume of liquid binder per voxel is not more than 90 percent of the first volume of liquid binder per voxel.

21 . The apparatus of claim 19 , wherein the controller is programmed to cause the at least one printhead to print the liquid binder into the powder at no more than 60 perce

Assignees

• Desktop Metal Inc

Inventors

• Preston Aaron
• Kilday Steve
• Heinze Mark

Classifications

• B22F12/90

  Means for process control, e.g. cameras or sensors · CPC title

• B22F12/50

  Means for feeding of material, e.g. heads · CPC title

• B22F12/38

  Housings, e.g. machine housings · CPC title

• B22F12/30

  Platforms or substrates · CPC title

• B22F10/14

  by jetting of binder onto a bed of metal powder · CPC title