U.S. patent application number 15/856038 was filed with the patent office on 2018-05-03 for three-dimensional printer with integrated coloring system.
The applicant listed for this patent is MakerBot Industries, LLC. Invention is credited to Taylor Michael Fahey, Charles John Haider, Michael Joseph Kobida, Cedric James Kovacs-Johnson, Tim Andreas Osswald.
Application Number | 20180117832 15/856038 |
Document ID | / |
Family ID | 54768853 |
Filed Date | 2018-05-03 |
United States Patent
Application |
20180117832 |
Kind Code |
A1 |
Haider; Charles John ; et
al. |
May 3, 2018 |
THREE-DIMENSIONAL PRINTER WITH INTEGRATED COLORING SYSTEM
Abstract
A three-dimensional printer effects color changes in an
extrudate using a color-application unit applying a colorant to the
interior of a filament before it is melted within an extruder.
Specifically, the color-application unit may receive a filament (or
portions thereof) having an exposed interior surface, where color
applicators are actuated to apply one or more colors to the
interior surface of the filament in order to modify the extruded
color. The filament may then be coupled, collapsed, or otherwise
closed about the interior surface, e.g., by a mechanical coupler,
to substantially enclose the interior surface of the filament,
which is then fed to the extruder for fabricating a colored object
in a three-dimensional fabrication process. By enclosing the
colored surface within the filament before melting for extrusion,
transition effects of a color change can be mitigated and
transition time for a substantially complete change in color can be
significantly reduced.
Inventors: |
Haider; Charles John; (St.
Paul, MN) ; Kobida; Michael Joseph; (Lake Barrington,
IL) ; Kovacs-Johnson; Cedric James; (Wilmette,
IL) ; Fahey; Taylor Michael; (Belle Plaine, MN)
; Osswald; Tim Andreas; (Madison, WI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MakerBot Industries, LLC |
Brooklyn |
NY |
US |
|
|
Family ID: |
54768853 |
Appl. No.: |
15/856038 |
Filed: |
December 27, 2017 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
14829023 |
Aug 18, 2015 |
9889607 |
|
|
15856038 |
|
|
|
|
14589841 |
Jan 5, 2015 |
9895844 |
|
|
14829023 |
|
|
|
|
62051944 |
Sep 17, 2014 |
|
|
|
61941899 |
Feb 19, 2014 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B29C 64/209 20170801;
B33Y 30/00 20141201; B29L 2009/00 20130101; B33Y 10/00 20141201;
B29C 64/106 20170801; B33Y 50/02 20141201; B29C 64/393 20170801;
B29C 64/118 20170801 |
International
Class: |
B29C 64/106 20170101
B29C064/106; B29C 64/386 20170101 B29C064/386; B33Y 30/00 20150101
B33Y030/00; B29C 64/20 20170101 B29C064/20 |
Claims
1. A three-dimensional printer comprising: an extruder configured
to deposit a build material in a three-dimensional printing
process; a coloring system including a color-application unit
disposed upstream from the extruder, the color-application unit
configured to receive a filament of the build material, the
color-application unit including a color applicator operable to
selectively apply a color to an interior surface of the filament
without applying color to an exterior surface of the filament; and
a drive assembly for moving the filament from the coloring system
to the extruder for depositing colored build material in the
three-dimensional printing process.
2. The three-dimensional printer of claim 1 further comprising a
coupler configured to receive the filament from the color
applicator and to substantially enclose the interior surface of the
filament that received the color before passing the filament to the
extruder.
3. The three-dimensional printer of claim 2 wherein the coupler is
connected to the extruder by a conduit, the conduit including a
pathway for the filament to travel between the coupler and the
extruder.
4. The three-dimensional printer of claim 2 wherein the
color-application unit and the coupler are integrated together as a
single unit.
5. The three-dimensional printer of claim 2 wherein the extruder
and the coupler are integrated together as a single unit.
6. The three-dimensional printer of claim 2 wherein the filament
includes a first filament portion and a second filament portion, at
least one of the first filament portion and the second filament
portion including the interior surface, and wherein the coupler is
configured to join the first filament portion to the second
filament portion to form the filament for extrusion in the
three-dimensional printing process.
7. The three-dimensional printer of claim 6 wherein the coupler
includes a body that has a first channel and a second channel,
wherein the first channel receives the first filament portion and
the second channel receives the second filament portion, and
wherein the first channel and the second channel converge within
the body to form a discharge channel that guides the filament
through the body.
8. The three-dimensional printer of claim 7 wherein the coupler
includes a motor and a roller assembly that is actuated by the
motor, and wherein the roller assembly engages the first filament
portion and the second filament portion to advance the filament
through the body.
9. The three-dimensional printer of claim 1 wherein the extruder
and the color-application unit are disposed within a build volume
of the three-dimensional printer.
10. The three-dimensional printer of claim 1 wherein the
color-application unit includes a plurality of color applicators,
each operable to selectively apply a different color to the
interior surface of the filament.
11. The three-dimensional printer of claim 1 wherein the
color-application unit includes a body, a conduit extending through
the body, and a motor that engages the filament to move the
filament through the conduit.
12. The three-dimensional printer of claim 11 wherein the
color-application unit includes a through-hole that extends through
the body and is communication with the conduit, and wherein the
color applicator includes an elongate member containing the color
and having a color applicator tip that is configured to apply the
color to the interior surface of the filament through the
through-hole, and wherein at least a portion of the elongate member
is slidably received within the through-hole to selectively engage
and apply the color to the interior surface of the filament.
13. The three-dimensional printer of claim 1 wherein the color
applicator includes an inkjet cartridge.
14. The three-dimensional printer of claim 1 wherein the extruder
is disposed in a printer head of the three-dimensional printer.
15. A method for three-dimensional fabrication of an object using a
three-dimensional printer comprising: receiving a filament at a
color-application unit of the three-dimensional printer, the
color-application unit positioned upstream of an extruder within
the three-dimensional printer; applying color to an interior
surface, but not an exterior surface, of the filament using a color
applicator coupled to the color-application unit; directing the
filament from the color-application unit to the extruder; and
extruding the filament to fabricate the object in a
three-dimensional printing process.
16. The method of claim 15 wherein the filament includes a first
filament portion and a second filament portion, at least one of the
first filament portion and the second filament portion including
the interior surface.
17. The method of claim 16 further comprising coupling the first
filament portion to the second filament portion to form the
filament for extrusion.
18. The method of claim 17 wherein a coupler that is positioned
downstream of the color applicator and upstream of the extruder
couples the first filament portion and the second filament
portion.
19. The method of claim 18 further comprising: receiving the first
filament portion in a first channel disposed in a body of the
coupler; receiving the second filament portion in a second channel
disposed in the body of the coupler; and joining the first filament
portion and the second filament portion within a discharge channel
formed by a convergence of the first channel and the second channel
within the body of the coupler.
20. A device comprising: a color-application unit configured for
placement upstream from an extruder configured to deposit a build
material in a three-dimensional printing process, wherein the
color-application unit is configured to receive a filament of the
build material; and a color applicator coupled to the
color-application unit and operable to selectively apply a color to
an interior surface, but not an exterior surface, of the filament
before the filament is passed to the extruder.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 14/829,023 filed Aug. 18, 2015, which is a
continuation-in-part of U.S. patent application Ser. No. 14/589,841
filed Jan. 5, 2015, which claims priority to U.S. Prov. Pat. App.
No. 62/051,944 filed Sep. 17, 2014 and U.S. Prov. Pat. App. No.
61/941,899 filed Feb. 19, 2014, where the entire content of each of
these applications is hereby incorporated by reference.
TECHNICAL FIELD
[0002] The disclosure relates to a three-dimensional printer with
an integrated filament coloring system.
BACKGROUND
[0003] Three-dimensional (3D) printing refers to the process of
creating a 3D object through an additive process, where successive
layers of material are laid down under the control of a computer.
Conventionally, a three-dimensional printer can use an extrusion 3D
printing process, which refers to a Fused Deposition Modeling (FDM)
process or a similar process where a build material is heated and
then deposited layer by layer onto a build platform. By adding many
thin layers on top of one another, sometimes hundreds or thousands,
a 3D object is created.
[0004] Typically, 3D printers include at least one printer head, or
extruder, containing a nozzle from which the melted build material
is extruded onto the build platform to create 3D objects. The build
material generally originates from an upstream feed of a raw
polymer in the form of a filament. This filament is fed into the
upper region of the extruder as a solid, where it is then melted
and deposited in its molten form from the extruder nozzle in a
continuous stream.
SUMMARY
[0005] A three-dimensional printer effects color changes in an
extrudate using a color-application unit that applies a colorant to
the interior of a filament before the filament is melted within an
extruder. Specifically, the color-application unit may receive a
filament (or portions of a filament) having an exposed interior
surface, where color applicators are actuated to apply one or more
colors to the interior surface of the filament in order to modify
the extruded color. The filament may then be coupled, collapsed, or
otherwise closed about the interior surface, e.g., by a mechanical
coupler, to substantially enclose the interior surface of the
filament, which is then fed to the extruder for fabricating a
colored object in a three-dimensional fabrication process. By
enclosing the colored surface within the filament before melting
for extrusion, transition effects of a color change can be
mitigated and the transition time for a substantially complete
change from one color to the next can be significantly reduced.
[0006] In one embodiment, the disclosure provides an assembly that
is configured to be coupled to and communicate with a 3D printer
having a printer head. The assembly includes a color-application
unit that is positioned upstream of the 3D printer. The
color-application unit is configured to receive a filament and
direct the filament to the printer head of the 3D printer. The
assembly also includes a color applicator coupled to the
color-application unit. The color applicator is operable to
selectively apply color to an interior surface of the filament.
[0007] In another embodiment, the disclosure provides a method for
preparing a filament for use with a printer head of a 3D printer.
The method includes receiving the filament at a color-application
unit positioned upstream of the 3D printer. The method also
includes applying color, by a color applicator coupled to the
color-application unit, to an interior surface of the filament. The
method further includes directing the filament from the
color-application unit to the printer head of the 3D printer.
[0008] In another embodiment, the disclosure provides a filament
for use with a printer head of a 3D printer. The filament includes
an exterior surface and an interior surface having color
selectively applied thereto. The color of the interior surface is
visible through the exterior surface.
[0009] Other aspects of the disclosure will become apparent by
consideration of the detailed description and accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The foregoing and other objects, features and advantages of
the devices, systems, and methods described herein will be apparent
from the following description of particular embodiments thereof,
as illustrated in the accompanying drawings. The drawings are not
necessarily to scale, emphasis instead being placed upon
illustrating the principles of the devices, systems, and methods
described herein.
[0011] FIG. 1 is a perspective view of a system including a 3D
printer and an assembly coupled to the 3D printer, the assembly
including a color-application unit, a color applicator, and a
coupler.
[0012] FIG. 2 is a plan view of the color-application unit, color
applicator, and coupler shown in FIG. 1.
[0013] FIG. 3 is a perspective view of a system including the 3D
printer and an assembly having a coupler according to another
embodiment of the invention.
[0014] FIG. 4 is a schematic view the systems of FIGS. 1-3.
[0015] FIGS. 5 and 6 illustrate a schematic diagram of fluid flow
through a nozzle of a 3D printer head.
[0016] FIG. 7 is an exploded perspective view of another
color-application unit for use with a 3D printer.
[0017] FIG. 8 is a perspective, first side view of the
color-application unit of FIG. 7.
[0018] FIG. 9 is a perspective, second side view of the
color-application unit of FIG. 7.
[0019] FIG. 10 is a perspective view of another color-application
unit for use with a 3D printer.
[0020] FIG. 11 is a side view of the color-application unit of FIG.
10.
[0021] FIG. 12 is an exploded view of the color-application unit of
FIG. 10.
[0022] FIGS. 13 and 14 illustrate another color-application unit
for use with a 3D printer.
[0023] FIG. 15 is a schematic of a system including the 3D printer
and an assembly according to another embodiment.
[0024] FIG. 16 is a schematic of the assembly of FIG. 15.
[0025] FIG. 17 is a schematic of another assembly for use with a 3D
printer.
[0026] FIGS. 18-20 illustrate filament shapes that can be used in a
color-changing system.
[0027] FIG. 21 illustrates a single piece filament.
[0028] FIG. 22 illustrates another single piece filament.
[0029] FIG. 23 illustrates a 3D object produced using conventional
coloring techniques.
[0030] FIG. 24 illustrates a 3D object produced using the
assemblies of FIGS. 1-3.
[0031] FIG. 25 is a block diagram of a three-dimensional
printer.
[0032] FIG. 26 is a flowchart of a method for three-dimensional
fabrication of an object using a three-dimensional printer.
DETAILED DESCRIPTION
[0033] The embodiments will now be described more fully hereinafter
with reference to the accompanying figures, in which preferred
embodiments are shown. The foregoing may, however, be embodied in
many different forms and should not be construed as limited to the
illustrated embodiments set forth herein.
[0034] All documents mentioned herein are hereby incorporated by
reference in their entirety. References to items in the singular
should be understood to include items in the plural, and vice
versa, unless explicitly stated otherwise or clear from the text.
Grammatical conjunctions are intended to express any and all
disjunctive and conjunctive combinations of conjoined clauses,
sentences, words, and the like, unless otherwise stated or clear
from the context. Thus, the term "or" should generally be
understood to mean "and/or" and so forth.
[0035] Recitation of ranges of values herein are not intended to be
limiting, referring instead individually to any and all values
falling within the range, unless otherwise indicated herein, and
each separate value within such a range is incorporated into the
specification as if it were individually recited herein. The words
"about," "approximately," or the like, when accompanying a
numerical value, are to be construed as including any deviation as
would be appreciated by one of ordinary skill in the art to operate
satisfactorily for an intended purpose. Ranges of values and/or
numeric values are provided herein as examples only, and do not
constitute a limitation on the scope of the described embodiments.
The use of any and all examples or exemplary language ("e.g.,"
"such as," or the like) is intended merely to better illuminate the
embodiments and does not pose a limitation on the scope of those
embodiments. No language in the specification should be construed
as indicating any unclaimed element as essential to the practice of
the disclosed embodiments.
[0036] In the following description, terms such as "first,"
"second," "top," "bottom," "above," "below," and the like, are
words of convenience and are not to be construed as limiting unless
expressly stated otherwise.
[0037] The following description emphasizes three-dimensional
printers using fused deposition modeling or similar techniques
where a bead of material is extruded in a layered series of two
dimensional patterns as "roads," "paths," or the like to form a
three-dimensional object from a digital model. It will be
understood, however, that numerous additive fabrication techniques
are known in the art including without limitation multijet
printing, stereolithography, Digital Light Processor ("DLP")
three-dimensional printing, selective laser sintering, and so
forth. Such techniques may benefit from the systems and methods
described below, and all such printing technologies are intended to
fall within the scope of this disclosure, and within the scope of
terms such as "printer," "three-dimensional printer," "3D printer,"
"fabrication system," and so forth, unless a more specific meaning
is explicitly provided or is otherwise clear from the context.
[0038] FIGS. 1, 3, and 15 illustrate a 3D printer 10 including a
printer head or extruder 14 that has a nozzle 18 and is slidably
positioned above a platform 22. The nozzle 18 (FIGS. 5 and 6)
includes walls 24 that define a channel 26 extending therethrough.
The channel 26 has an inlet 30 and an outlet 34. The channel 26
also has a diameter D that decreases from the inlet 30 to the
outlet 34.
[0039] FIGS. 1-3 illustrate a color-application and feed assembly
100 that is configured to be coupled to and communicate with the 3D
printer 10. The illustrated assembly 100 includes a
color-application unit 104 and color applicators 156. In the
illustrated embodiment, the assembly 100 includes six color
applicators 156, but may alternatively include fewer or more color
applicators 156. Each color applicator 156 is coupled to (e.g.,
supported by) the color-application unit 104 to apply color to a
surface of a filament (e.g., first filament portion 144 discussed
below). The assembly 100 also includes a coupler or annealing unit
108 positioned between the color-application unit 104 and the 3D
printer 10. In the illustrated embodiment, the color-application
unit 104 and the coupler 108 are coupled to and positioned within a
support structure or frame 112.
[0040] In the embodiments illustrated in FIGS. 1-3, the
color-application unit 104 includes a body 120 that defines a
longitudinal axis A. The body 120 includes first end 124, a second
end 128, a first side 132, and a second side 136. In the
illustrated embodiment, the body 120 is formed as a single piece,
but in other embodiments, the body 120 may be formed of separate
pieces that are coupled to one another. The body 120 further
includes a first channel or conduit 140 that extends from the first
end 124 to the second end 128. The conduit 140 is sized and shaped
to receive a first filament, or strand, portion 144 from a first
spool 148 positioned adjacent the first end 124 of the body 120.
The first filament portion 144 may be any suitable material having
any suitable size or shape, as discussed in greater detail below.
In the illustrated embodiment, the first filament portion 144 is
substantially cylindrical or rod-shaped and may have a diameter in
the range of 0.5-3.0 mm, with a preferable diameter of about 1.75
mm.
[0041] The body 120 also defines through-holes or apertures 152
extending from each of the first side 132 and the second side 136
towards the conduit 140. Each of the through-holes 152 is
configured to movably (e.g., slidably) receive one of the color
applicators 156. In the embodiment illustrated in FIGS. 1-3 and
7-9, the color applicator 156 is an elongate member 158 that has a
color applicator tip 158a. The elongate member 158 contains a color
material and dispenses the color material through the tip 158a. For
example, the elongate member 158 may be a felt-tip marker or pen.
Other embodiments utilize although other types of color applicators
156, which will discussed in greater detail below. Also, in the
embodiments illustrated in FIGS. 1-3, the through-holes 152 are
oriented at an angle .theta. relative to the longitudinal axis A
(FIG. 2) of the body 120. In some embodiments, the angle .theta.
can range from about 20 degrees to about 70 degrees. In the
illustrated embodiment, the angle .theta. is about 30 degrees. In
further embodiment, the angle .theta. may be larger or smaller than
that illustrated herein. In the illustrated embodiment, the body
120 also includes apertures 160 that are oriented generally
perpendicular to the longitudinal axis A. Each of the apertures 160
corresponds to one of the through-holes. The apertures 160 enable
the color applicators 156, and more particularly the tips 158a, to
communicate with the filament portion 144 in the conduit 140 to
selectively apply color to the filament portion 144. The apertures
160 give the user the ability to see the color applicators 156, and
more particularly the tips 158a, during a visual calibration
process.
[0042] As shown in FIG. 2, the color-application unit 104 also
includes a motor assembly 164. The illustrated motor assembly 164
includes a motor and a roller that engages the filament portion
144. The motor drives (e.g., rotates) the roller to move the
filament portion 144 through the conduit 140 of the body 120. In
the illustrated embodiment, the motor assembly 164 is positioned
above the body 120 to pull the filament portion through the conduit
140. In other embodiments, the motor assembly 164 may be positioned
elsewhere relative to the body 120 to push or pull the filament
portion 144 through the conduit 140.
[0043] Further with respect to FIGS. 1-3, the support structure 112
has two members 170 that are coupled to a support surface 174 on
either side of color-application unit 104. The color applicators
156 are coupled to the members 170 by actuators 176 (FIG. 2). In
the illustrated embodiment, the color applicators 156 are biased
(e.g., by a spring, a cam, a lever, or the like) to a first
position such that the color applicator tips 158a are spaced apart
from the conduit 14. Each of the actuators 176 is selectively
actuatable by (e.g., rotatable, slidable, or otherwise moveable) by
a motor 176a. Actuating the actuators 176 moves the color
applicators 156 toward the conduit 140 to apply color to the
filament portion 144 within the conduit 140.
[0044] The illustrated support members 170 also support a second
spool 180 and a third spool 184, which include second and third
filament, or strand, portions 188, 192, respectively. The second
and third filament portions 188, 192 may be any suitable material
having any suitable size or shape. With reference to FIG. 19a, in
the illustrated embodiment, each of the second and the third
filament portions 188, 192 include a substantially C-shaped body
200 having a substantially arcuate groove 204. Accordingly, the
second and the third filament portions 188, 192 each define a wall
208 having a thickness tin the range of approximately 0.01-1.5 mm,
with preferably thickness of 0.5 mm. The second and the third
filament portions 188, 192 are substantially clear or transparent
(e.g., colorless).
[0045] Referring back to FIGS. 1-3, the coupler 108 is spaced apart
from the color-application unit 104 and the spools 148, 180, 184.
The illustrated coupler 108 is positioned downstream of the
color-application unit 104 and upstream of the 3D printer 10. In
the illustrated embodiment, the coupler 108 is suspended above the
color-application unit 104. In other embodiments, the coupler 108
may be positioned elsewhere. With respect to FIG. 2, the coupler
108 includes a body 220 having a first end 224 and a second end
228. The body 220 includes a first channel 232 having a first inlet
236, a second channel 240 having a second inlet 244, and a third
channel 248 having a third inlet 252. The inlets 236, 244, 252 are
positioned at the first end 224 of the body 220. The first, the
second, and the third channels 232, 240, 248 extend through the
body 220 and converge into a single discharge channel 260 having an
outlet 264 at the second end 228 of the body 220. A roller assembly
268 that is actuated by a second motor 270 is positioned adjacent
the first end 224 of the coupler 108. A conduit 274 (FIG. 1)
extends between the coupler 108 and the printer head 14. In the
embodiment illustrated in FIGS. 1-2, the coupler 108 includes
first, second, and third portions 232', 240', 248' that are spaced
apart from one another through which the first, the second, and the
third channels 232, 240, 248 extend, respectively. The first,
second, and third portions 232', 240', 248' are coupled to one
another to define the discharge channel 260. In the embodiment of
FIG. 3, however, the first, second, and third channels 232, 240,
248 are contained within and extend along a substantially
rectangular body 220. The first, the second, and the third channels
232, 240, 248 converge within the body 220 adjacent to the second
end 228 of the coupler 108 prior to being guided through the
conduit 274, as noted above.
[0046] In operation and with reference to FIGS. 1-4, the first
filament portion 144 is advanced by the first motor 164 from the
first spool 148 and moves through the conduit 140 in the body 120
of the color-application unit 104. As the first filament portion
144 advances through the body 120, the color applicators 156 are
selectively actuated (e.g., by selectively energizing the motors of
the actuators 176) to apply color to a portion of the first
filament portion 144. For example, the motor 176a actuates the
actuators 176 to slide or move the respective the color applicator
156 towards the conduit 140 and into a second position in which the
color applicator tip 158a contacts the first filament portion 144.
When the tip 158a engages the first filament portion 144, the
applicator 156 applies color to filament portion 144. As used
herein, "color" refers to a material or substance (e.g., ink,
coating, etc.) that is applied to the filament portion 144 to
change or enhance (e.g., brighten or strengthen) the color of the
filament portion 144. The color may be any color or mixture of
colors, including white.
[0047] After a color is applied, the first filament portion 144 is
then guided to the first inlet 236 in the coupler 108. At the same
time, the second and third filament portions 188, 192 are guided to
the second and third inlets 244, 252 of the coupler 108,
respectively. Preferably, the second and third filament portions
188, 192 are guided through the coupler 108 such that the grooves
204 (FIG. 19a) face one another. Accordingly, the first, second,
and third filament portions 144, 188, 192 are guided through the
respective channels 232, 240, 248 from the first end 224 of the
coupler 108 to the second end 228. In other words, the motor 270
actuates the roller assembly 268 to advance each of the first,
second, and third filament portions 144, 188, 192 through the
second, first, and third channels 232, 240, 248, respectively, of
the coupler 108. Where the first, second, and third channels 232,
240, 248 converge, the grooves 204 of the second and the third
filament portions 188, 192 receive the first filament portion 144
therebetween. Once the first filament portion 144 is positioned
between the second and third filament portions 188, 192, the second
and third filament portions 188, 192 are pressed together or
otherwise mechanically coupled to create a filament 290. The second
and third filament portions 188, 192 thereby substantially enclose
the first filament portion 144 to create the filament 290. The
filament 290, when coupled together, defines a cylindrical shape
having a diameter in the range of 1.0 mm to 5.0 mm such that the
filament 290 may be used with a suitable 3D printer (e.g., the
printer 10 (FIGS. 1 and 3)).
[0048] The filament 290 defines a filament profile 294 that
includes the first, colored filament portion 144 surrounded or
encompassed by the second and the third filament portions 188, 192.
As such, the filament 290 includes an exterior surface 298 and an
interior surface 300. In the embodiment of the assembly 100
discussed above, the exterior surface 298 is defined by the second
and third filament portions 188, 192, and the interior surface
includes the first filament portion 144. In the embodiment of FIGS.
1-3 and 19a, the color applied to the filament 290 is applied to
surface 300 and covered by surfaces 204 of filament portions 188
and 192. The filament portions 188, 192 are transparent so the
color material is visible from the outside of the filament 298.
[0049] After the filament 290 is formed, the filament 290 moves
from the coupler 108 to the printer head 14 through the conduit
274. The printer head 14 is configured to heat and melt the
materials of the filament 290 such that the melted material can
move through and be deposited by the nozzle 18 onto the platform
22. In particular, the filament 290 is fed into an upper region of
the printer head 14 as a solid, where it is then melted into its
molten form. The molten form of the filament 290 is guided through
the channel 26 in the nozzle 18 and deposited from the nozzle 18 in
a continuous stream. Accordingly, the nozzle 18 deposits the
material onto the platform 22 layer-by-layer to build 3D objects
from a bottom surface to a top surface.
[0050] With respect to FIG. 5, typically when a filament 312 is
pushed through the nozzle 18, the friction between the walls 24 of
the nozzle 18 and the exterior surface of the filament 312 cause
the outer portions of the filament 312 to move slower than the
remainder of the advancing filament 312. The wall friction creates
a velocity profile that can be seen in FIG. 5. As illustrated, the
material at the center of the nozzle 18 can be seen moving much
faster than the material at the edges. This causes some of the
material from the outermost edges of the filament 312 to be left
behind and mixed into the filament later on in the printing
process.
[0051] Additionally, when the extrusion nozzle 18 decreases in
diameter, stagnant flow or eddies 308 (FIG. 5) occur. Eddies
commonly form around sharp transitions in the flow within the
nozzle 18. Eddies 308 cause the material to slowly circulate. As
this material slowly circulates, it pulls additional material from
the outer edges of the new material flowing past the eddies 308,
and pushes old material back into the material currently flowing
by. FIGS. 5 and 6 illustrate the effect of introducing the color to
the exterior surface of a filament. As illustrated in FIG. 6, when
color is applied an interior surface of the filament (in accordance
with the present invention), the color is prevented from sticking
to the walls 24 of the nozzle 18 and getting caught in eddies 308
during nozzle diameter changes.
[0052] In accordance with preferred embodiments discussed herein,
color is applied to the interior surface 300 of the filament 290.
However, in other embodiments color can be applied to the surfaces
204 of elements 188 and 192, or to all of the inner surfaces 204
and 300 of the filament 290. Having color only on the inner
portions or surfaces of the filament 290 overcomes the problem of
cleanly transitioning from one color to another. In other words,
while color can also or alternatively be added directly to an
exterior surface of the filament 312 or other build material in the
above-described continuous process, if the color is applied to the
exterior surface or the filament 290 transitioning from one color
to another requires an extended period of time to flush the
previous color material out of the nozzle because colored material
will be left behind as a result of the wall friction, as described
above. Additionally, eddies 308 can be responsible for producing
old colors once a new color has already been fully realized if
color is on an exterior surface of the filament. A 3D object that
has been colored using a filament that has color on an exterior
surface is illustrated in FIG. 23.
[0053] In contrast, adding color to the interior surfaces 300 of
the filament 290 substantially eliminates the issues caused by both
wall friction and eddies 308 and, therefore, streamlines switching
among different colors. This is because the first, colored filament
portion 144 (e.g., the interior surface 300 of the filament 290) is
surrounded by the second and third filament portions 188, 192
(e.g., the exterior surface 298), which are substantially clear or
transparent. Accordingly, the material left behind is also
substantially clear or transparent and does not affect subsequent
colors being run through the nozzle 18. In other words, color is
inhibited from sticking to the walls 24 of the nozzle 18 and
getting caught in eddies 308 during diameter changes of the nozzle
18. A 3D object that has been colored using the filament 290
described above, that is with color on the interior surface 290, is
illustrated in FIG. 24. The comparison between FIGS. 23 and 24
illustrates how colors can change more quickly or sharply (e.g.,
within fewer layers) and how the color is less blurred in the 3D
object of FIG. 24. For example, the transition distance between
colors applied to the center of the filament is 0-5 cm, whereas the
transition distance between colors when coloring the exterior of
the filament ranged from 10-100 cm. This 95% reduction in
transition distance allows the 3D printer 10 to be used to produce
more detail when coloring parts.
[0054] The color-application unit 104 may have other configurations
other than those illustrated in FIGS. 1-3 for applying color to
interior surfaces of the filament 290. For example, in the
embodiment of FIGS. 1-3, the color-application unit 104 is
configured to hold three color applicators 156 on each side of the
body 120. However, in the embodiment illustrated in FIG. 7-9, a
color-application unit 104 can accommodate only one color
applicator 156 on each side of 120. Therefore, multiple
color-application units 104 may be positioned appropriately
relative to one another to administer different colors to the first
filament portion 144. The illustrated color-application unit 104 of
FIGS. 7-9 allow the system be easily scaled to accommodate any
desired number of different colors (e.g., two, four, ten, twenty,
etc.).
[0055] Further with respect to FIGS. 7-9, the color-application
unit 104 is configured to removably receive color applicators 156
on each side of the body 120. In particular, the color-application
unit 104 includes holders or holsters 320 that are each configured
to removably receive one of the color applicators 156. Each color
applicator 156 is secured into place in the holster 320. Each color
applicator 156 is also engaged or disengaged by a motor 176a to
control when the color is dispensed onto a portion of the first
filament portion 144 to apply the color. The color applicators 156
can be changed out for different color applicators 156 containing
different colors, as needed.
[0056] While the color-application unit 104 and the coupler 108 are
configured as separate structures in the embodiments of FIGS.
10-12, in other embodiments, the color-application unit and the
coupler may integrated into a single unit or structure (e.g.,
color-application unit 350 illustrated in FIGS. 10-12).
[0057] As shown in FIGS. 10-12, the color-application unit 350
includes a body 354 having a first member 358 that is coupled to a
second member 362. An interior surface 366, 370 of each of the
first and the second members 358, 362 defines three grooves 374,
378, 382. The first groove 374 is positioned between the second
groove 378 and the third groove 382. Additionally, through-holes or
apertures 386 extend from an exterior surface 390, 394 of each of
the first member 358 and the second member 362 to the interior
surface 366, 370 of each of the first member 258 and the second
member 362. Each of the through-holes 386 is configured to slidably
receive a color applicator 156. Also, in embodiment illustrated in
FIGS. 10-12, the through-holes 286 are oriented at an angle .theta.
relative to the longitudinal axis A. In some embodiments, the angle
.theta. can range from about 20 degrees to about 70 degrees. In the
illustrated embodiment, the angle .theta. is about 45 degrees. In
further embodiments, the angle .theta. may be larger or smaller
than that illustrated herein.
[0058] When the first member 358 and the second member 362 are
coupled together, the first grooves 374 define a first channel or
conduit 410, the second grooves 378 define a second channel 414,
and the third grooves 382 define a third channel 418. The first,
second, and third channels 410, 414, 418 extend from a first end
422 of the body 354 to a second end 426 of the body 354. At the
first end 422 of the body 354, the first, second, and third
channels 410, 414, 418 are spaced apart from one another. As the
channels progress through the body 354, the distance between
adjacent channels decrease until the three channels 410, 414, 418
converge into a single discharge channel near the second end 426 of
the body 354. A motor assembly (similar to the motor assembly 164
discussed above) can be positioned adjacent to the first end 422 of
the body 354 and can include rollers that engages the filament
portions 144, 188, 192 to drive the filament portions 144, 188, 192
through the body 354.
[0059] In operation, the first, second, and third filament portions
144, 188, 192 are pulled by the motor assembly from their
respective spools 148, 180, 184. The first, second, and third
filament portions 144, 188, 192 move through the first, second, and
third channels 410, 414, 418, respectively, in the body 354 of the
color-application unit 104. As the first filament portion 144 moves
through the body 354, the color applicators 156 are selectively
actuated to apply color to the first filament portion 144, as
discussed above with respect to FIGS. 1-3. Near the second end 422
of the body 354, the filament portions 144, 188, 192 converge (as
discussed above with respect to the embodiment of FIGS. 1-3) to
create the filament 290, which is guided to the 3D printer 10. In
particular, in the embodiment of FIGS. 10-12, the second and third
channels 414, 418 guide the second and third filament portions 188,
192 to each gradually make a 90 degree turn so that the filament
portions 188, 192 wrap around the first filament portion 144 as
they exit the body 354.
[0060] In the embodiments of FIGS. 1-3 and 7-10, the color
applicators 156 are elongate members 158 (e.g., markers) that
contain and dispense color, as discussed above. In other
embodiments (FIGS. 13 and 14), however, the color applicators 156
of the color-application unit may be inkjet cartridges 450. In some
embodiments, the cartridges 450 are piezoelectric inkjet cartridges
that are actuated via a processor to selectively apply color to the
first filament portion 144.
[0061] The piezoelectric inkjet cartridge 450 includes a printhead
454 that uses a pulse generator to provide an electric signal. The
signal is applied across piezoelectric crystal plates, one of which
contracts and the other of which expands, thereby causing the plate
assembly to deflect toward a pressure chamber. This causes a
decrease in volume, which imparts sufficient kinetic energy to the
liquid dye in the printhead nozzle 458 so that an ink droplet of
the liquid dye is ejected from an opening in the printhead 454.
Examples of suitable piezoelectric-activated inkjet cartridges 450
may be found in U.S. Pat. No. 4,549,191; U.S. Pat. No. 4,584,590;
U.S. Pat. No. 4,887,100; U.S. Pat. No. 5,016,028; U.S. Pat. No.
5,065,170; and U.S. Pat. No. 5,402,162.
[0062] The liquid dyes may be contained within a plurality of feed
containers equipped with metering devices (not shown) to control
the rate and amount of dye or other compositions applied to the
filament 10.
[0063] FIG. 13 illustrates the use of one piezoelectric inkjet
cartridge 450 to apply color in the form of a liquid dye. FIG. 14
illustrates the use of multiple inkjet cartridges 450 to apply
multiple colors to achieve a greater breadth of color options for
the final 3D object.
[0064] In additional or alternative embodiments, the color
applicator 156 may be a thermal inkjet, pressure inkjet, a piezo
pump, a pressure pump, a spray mechanism (e.g., using air or
pressure), a microfluidic device (e.g., a syringe system), or a
stamping or rubber applicator.
[0065] In some embodiments, a "fixing region" may be included
downstream from the color-application unit 104 where the color is
completely or partially fixed to the filament portion 144. For the
purposes of the present technology, "fixing" refers to ensuring
incorporation of the color on the surface of at least a portion of
a filament prior to the coupler. This fixing may be due to
polymerization, binding, drying, hardening, crosslinking, addition
reaction, or any other process that ensures the color remains
incorporated on the filament portion 144 during and after the
printing process. For example, in some embodiments the fixing
region may be a thermal drying unit (not shown) and/or may include
a gas, air jet, or fan (not shown) to assist in drying or otherwise
fixing the color to the filament portion 144. Still in other
embodiments, the color on the filament portion 144 may be air-dried
over a period of time prior to entering the coupler.
[0066] The embodiments illustrated in FIGS. 1-3 and 10-12
illustrate color-application and feed assemblies in which three
filament portions 144, 188, 192 are combined or coupled to create
the filament 290 that is fed to the 3D printer. It should be
understood, however, that the filament 290 may be constructed from
fewer or more filament portions. For example, FIGS. 15-17
illustrate color-application and feed assemblies 500 in which two
filament portions 504, 508 are combined or coupled to create the
filament 290 that is fed to the 3D printer. As illustrated in FIGS.
18 and 19, first and second filament portions 504, 508 include a
half-cylinder filament profile 294. The half-cylinder filament
portions 504, 508 may be constructed from splitting formerly
cylindrical filament or may be manufactured as such. Accordingly,
color is applied to an interior surface 512, 516 of each of the
first and the second filament portions 504, 508. In some
embodiments, the two filament portions 504, 508 may be split to
expose the interior surfaces 512, 516 and apply color, yet still
remain connected together.
[0067] As shown in FIGS. 15-17, the color is applied to the
interior surfaces 512, 516 of the filament portions 504, 508 via
the color applicators 156 before the first and the second filament
portions 504, 508 are coupled together to create the filament 290.
This allows the on-demand or continuous incorporation of color to
the interior surfaces 300 of the filament 290, as opposed to
coating the exterior surface 298 of the filament 290, allowing for
enhanced multi-coloring of 3D objects.
[0068] The schematic diagram of FIG. 4, discussed above, also
applies to the operation of the color-application and feed assembly
500 of FIGS. 15-17 and the 3D printer 10. With respect to FIG. 15,
each filament portion 504, 508 are introduced to the color
applicator 104. In particular, each of the filament portions 504,
508 are pulled from their respective spools 520, 524 through the
color-application unit 104 by motorized rollers 528, one for each
filament portion 504, 508, respectfully. In other embodiments, the
motorized rollers 528 may be alternatively controlled by a single
motor, which may be the same motor that also controls a feeder in
the 3D printer 10. The motorized rollers 528 pull each filament
portion 504, 508 through the color-application unit 104 and into
the coupler 108 at the same rate. Alternatively, each motorized
roller 528 may be controlled by separate motors working at the same
rate. Accordingly, one or more colors are applied to the interior
surfaces 512, 516 of the filament portions 504, 508, as directed by
the user. After applying the color to the surface 512, 516 of the
filament portions 504, 508, the two filament portions 504, 508 are
joined together in the coupler 108 to create the filament 290. The
colored surfaces 512, 516 of the filament portions 504, 508 make up
interior surfaces 300 of the filament 290. Once coupled, the
filament 290 is introduced to the 3D printer 10, where the filament
290 is heated and extruded from the extruder nozzle 18 layer by
layer onto a build platform 22, as discussed above. This results in
a multicolored 3D object.
[0069] FIGS. 16 and 17 illustrate alternative placements of the
motorized rollers 528 that could be used to control and guide the
filament portions 504, 508 to the 3D printer. FIG. 16 includes the
set of motorized rollers 528 upstream of the color-application unit
104. FIG. 17 illustrates the use of a single motorized roller 528
downstream from the coupler 108 and upstream of the printer head
14.
[0070] It may be preferable to use any combination of these or
other motorized roller 528 placements to convey the filament
portions 504, 508 to the 3D printer 10. It may also be preferable
to include additional braking rolls and a guiding system (not
pictured) to provide consistent tension in each filament portion
504, 508 as they are pulled through the color-application unit 104
and introduced into the coupler 108.
[0071] FIGS. 18-20 illustrate filament shapes that can be used with
a color-changing system as contemplated herein. As shown in FIG.
18, the filament 290 may include one or more filament portions 504,
508 having interior surfaces 512, 516 therein. In an aspect with
two filament portions 504, 508 (such as the implementation shown in
the figure), the filament 290 may include a bifurcated filament.
One skilled in the art will recognize that additional filament
portions 504, 508 are also possible (e.g., three or more), or the
filament may be a single piece filament. In the bifurcated filament
shown in the figure, the two filament portions 504, 508 may each
represent about one-half of the filament 290. One or more of the
filament portions 504, 508 may include a void, groove 517, or other
cutout. For example, the one or more filament portions 504, 508 may
include a groove 517 such that it resembles a pipe bisected along
its longitudinal axis (i.e., an elongated half-pipe). As explained
herein, one or more of the filament portions 504, 508 may travel
through a coloring device or system where dye is applied to one or
more of the grooves 517 (or otherwise to an interior surface of the
filament 290) and then the portions of filament are joined together
to form a single piece of filament (e.g., through heat applied by a
coupling device, crimper, or the like). In an embodiment, color is
applied to each of the filament portions 504, 508. In another
embodiment, color is only applied to one portion of the filament
290. In an embodiment, each of the filament portions 504, 508 may
include a groove 517, or only one portion of the filament 290 may
include the groove 517. The filament portions 504, 508 may be
completely separate from one another before coupling. In another
aspect, the filament portions 504, 508 may be adjoined or connected
in some manner, but can be split apart (or otherwise separated,
e.g., completely or partially) for the application of color. This
may be advantageous when coupling the filament, or otherwise
reforming it to conform to resemble a standard filament strand of
the prior art.
[0072] In additional or alternative embodiments, a single filament
or greater than three filament portions may be used. FIG. 20
illustrates several examples of potential filament profiles (e.g.,
cross-sections) that could be used to apply color to an interior
surface of a filament. The examples illustrated in FIG. 20 are not
intended to be an exclusive list. For example, FIG. 20 illustrates
several examples of additional filament profile shapes, including
single, whole filament strands, third strands, and quarter strands
that may be used to improve coupling and/or color application and
subsequent saturation and is not intended as an exhaustive list.
Therefore, filaments 290 comprising between one and six coupled
filament portions may be colored by one of the color-application
units described herein and introduced into a coupler for use with a
3D printer 10.
[0073] While the exemplary filament profiles 294 are by no means
exhaustive, the filament profiles may be configured as a "star"
shape 600 or "cross" shape 604. Further the filament profiles may
be a "step shaped" profile 608, a "notch shaped" profile 612,
"diamond-notch shaped" profile 616, "Z-shaped" profile 620 or other
variations either included in FIG. 20 or otherwise. Other example
of filament profiles may include a "tooth-and-comb" shape or a
"notch-and-lock" shape.
[0074] The "Z-shaped" profile 620 shown in FIG. 20 may include one
or more grooves 622 exposing an interior surface for coloring. The
grooves 622 may be sized and shaped to cooperate with color
applicators for coloring the interior surface of the filament. In
other words, the size and shape of the grooves 622 may correspond
with the size and shape of the applicator(s). For example, in the
figure, the grooves 622 are shown as substantially triangular
cutouts, which may correspond to a substantially triangular-shaped
color applicator tip. As shown in the figure, the grooves 622
extend substantially through the profile of the filament in an
implementation, but other implementations with deeper or shallower
grooves 622 are also or instead possible.
[0075] A deformable profile 624 made of a single piece of filament
may also or instead be used in the devices, systems, and methods
discussed herein. The deformable profile 624 may include a single
piece of filament that can be manipulated, deformed, re-shaped,
reconfigured, bent, folded, crimped, and the like. In an aspect,
the deformable profile 624 is deformable to close or seal (or
substantially close or seal) its interior surface 626. For example,
the deformable profile 624 may include a first state 628 in which
the interior surface 626 is exposed (or partially exposed, e.g.,
through a movable/deformable wall or membrane), and a second state
630 in which the interior surface 626 is unexposed (or partially
unexposed, sealed, closed, and so on). In an implementation, the
deformable profile 624 includes one or more sections (e.g., a first
half 632 and a second half 634) joined together, where the sections
can be reshaped to resemble the profile of a standard filament,
e.g., a rod, a tube, a ribbon, a strand, and so on. In this manner,
the filament need only be reshaped, and not mechanically coupled,
in order to be fed into a standard extruder of a three-dimensional
printer. The reshaping of the filament may instead include
crimping, coupling, sealing, heat treating, adhering, and so on,
e.g., to secure the filament in its reshaped state. Alternatively,
as stated above, the reshaping may simply involve manipulating or
deforming the filament without a need for any mechanical or thermal
attachment. In aspects, only certain portions of a length of
filament are mechanically or thermally attached (e.g., certain
sections can be "spot welded" together or the like over the length
of the filament strand).
[0076] A notched, single-piece filament 636 may also or instead be
used in the devices, systems, and methods discussed herein. The
notched, single-piece filament 636 may include a notch 638 exposing
or partially exposing an interior surface 640. The notch 638 may be
relatively small compared to the profile of the filament, i.e.,
resembling a slit or the like, or the notch may take up a
substantial portion of the perimeter of the filament, or anything
in-between. The notch 638 may be shaped and sized to cooperate with
a color applicator. For example, the notch 638 may be shaped and
sized such that the color applicator can penetrate through the
notch 638 to apply color to the interior surface 640, but otherwise
the filament resembles a standard filament for ease in use/handling
and for its compatibility with three-dimensional printers and
components thereof. In other words, the notch 238 may only be as
large as necessary for receiving a color applicator therein. The
interior of the filament may be hollowed out (or substantially
hollowed out) as shown in the figure, e.g., exposing a relatively
large amount of the interior surface 640 therein for coloring.
Alternatively, the interior of the filament may only be accessible
for a width equal to that of the width of the notch 638, or it may
include a smaller width than the notch 638. Other configurations
are also or instead possible, such as including an interior having
an interior shape or protrusion 642 disposed therein. The
protrusion 642 may be shaped and sized to create a predetermined
surface area for coloring, or shaped and sized to cooperate with a
color applicator. The protrusion 642 may include an extension of
the interior (as shown in the figure), or it may also or instead
include carved out portions of the interior (e.g., interior notches
or patterns). In an aspect, the notch 638 or the like may be
mechanically, thermally, chemically, or otherwise sealed or
partially sealed before extrusion. This sealing may be performed by
the coupler as described herein, a crimping device, or another
device. The coupler may simply press the notch 638 closed (or
substantially closed) without sealing the notch 638 in an
embodiment. In an aspect, the notch 638 instead remains in the
filament when the filament is feed into an extruder of a
three-dimensional printer.
[0077] It will be appreciated that a wide range of shapes may be
used with an interior surface that can receive a dye or other
colorants for color changing operations. Thus, an "interior
surface" as that term is used herein may be any surface that is
contained within a perimeter of the cross-sectional shape of the
filament (e.g., inside a two-dimensional convex hull of the
cross-sectional shape), or any surface that can be manipulated into
the convex hull by mechanically deforming the cross-sectional shape
prior to melting. While this is a useful working definition for
interior surfaces, other definitions may also or instead be
employed. For example, the interior surface may be any point or
group of points inside a maximum distance from a center of mass of
the two-dimensional cross-sectional shape. In another aspect, the
interior surface may be any surface having a normal angle less than
ninety degrees away from the center of mass. This definition does
not include all interior surfaces that might be used for all
cross-sections, but it usefully describes a range of interior
surfaces for one-piece shapes such as approximately circular
filaments with grooves approaching or passing through the center of
mass, which might have color applied to them as contemplated
herein. Where two or more pieces of filament are used, or where a
single piece of filament is deformed, the interior surface may
include any contact surface between portions of the filament except
for exposed seams, i.e., seams on the exterior of the filament
after it is closed or collapsed around the interior surfaces. More
generally, these various working definitions of an "interior
surface" are provided by way of non-limiting examples of an
interior surface that can receive an application of a dye or other
colorant in a manner such that contact of the colorant with
interior surfaces of an extruder during melt and extrusion is
reduced or minimized as contemplated herein.
[0078] FIG. 21 illustrates a single piece filament. The filament
2100 may include an exterior portion 2102, an interior portion
2104, and a slit 2106.
[0079] The exterior portion 2102 may be rounded or otherwise shaped
and sized such that the filament 2100 resembles standard build
material filaments of the prior art.
[0080] The interior portion 2104 may be the area or volume in which
color is applied by the devices or systems as described herein.
[0081] The slit 2106 may include a void or groove that connects the
exterior portion 2102 to the interior portion 2104, such that a
color applicator can apply a color to the interior portion 2104.
The color applicator may penetrate the slit 2106 or the color
applicator can apply the color from outside of the slit 2106, e.g.,
by spraying, jetting, or the like. The slit 2106 may have a uniform
or varying shape. For example, the slit 2106 may resemble a wedge
shape, or an inverse wedge shape. In another aspect, the slit 2106
includes a pattern, e.g., a zig-zag, a wave, and so on. In yet
another aspect, the filament 2100 includes a plurality of slits
2106. The plurality of slits 2106 may engage with a plurality of
color applicators. In an aspect, the slit 2106 may be covered or
partially covered by a membrane that can be pierced or punctured by
the color applicator. The piercable membrane may be formed by a
relatively thin wall of the filament 2100, e.g., a portion along
the exterior portion 2102 of the filament 2100 adjacent to the slit
2106.
[0082] Although the filament 2100 may include many different sizes
and shapes having different dimensions, one example is provided
herein for illustration. In one aspect, the outer diameter of the
filament is about 2.85 mm, with a slit 2106 having a depth that
extends approximately halfway through the filament 2100, i.e., to
its approximate center 2108. The slit 2106 may include a width of
0.5 mm, for example. The slit 2106 may instead have other widths,
e.g., 1 mm, and/or other depths. In an aspect, the smaller the
width of the slit 2106, the less recirculation of dye, which can
result in bold colors and desirable transitions of color. However,
the smaller the slit 2100, the more difficult it may be to apply
the color therein.
[0083] FIG. 22 illustrates another single piece filament. The
filament 2200 may include an exterior portion 2202, an interior
portion 2204, and a slit 2206.
[0084] The slit 2206 may be wider and/or deeper than the
implementation described above. For example, the slit 2206 in the
figure is shown extending well beyond the approximate center 2208
of the filament 2200. In an aspect, the wall 2210 between the
exterior portion 2202 and the end of the slit 2206 is approximately
0.5 mm.
[0085] The embodiments described above, or any other embodiments
including a single piece filament, may have color applied to an
interior portion thereof, and then be fed into an extruder "as is."
Typically, this is made possible by the shape of the filament,
which can substantially resemble a standard filament strand of the
prior art. It is also or instead possible to couple, crimp, clamp,
secure, or otherwise alter or deform the single piece filament
after color is applied to an interior portion thereof but before
being fed into an extruder of a three-dimensional printer. In an
implementation, a coupler or the like presses portions of the
single piece filament together such that the filament has a profile
resembling that of a standard filament strand of the prior art. In
this manner, the single piece filament may be deformable. The
deformation may take place within the extruder of a
three-dimensional printer or another device (either within or
separate from the three-dimensional printer). In another
implementation, the coupler or the like secures portions of the
single piece filament together, e.g., through heating the filament
or otherwise fixedly engaging portions of the filament
together.
[0086] To achieve these profiles, a number of manufacturing
processes can be implemented. The most common practice is the use
of an extruder die that can be machined to the desired profile of
the filament. The plastic can be extruded through the die to create
the desired filament profile. In addition, a series of rollers
and/or colanders can also be used with an extrusion system to shape
the extruded plastic into the desired filament profile. These are
two examples, not an extensive list, of the possible processes.
[0087] The filament portions 144, 188, 192, 504, 508 described
herein may be constructed of any material that is compatible with
3D printers. In particular, the filaments and filament portions
thereof may be constructed from poly lactic acid (PLA) and
acrylonitrile-butadiene-styrene (ABS) thermoplastic, which is
commonly used with 3D printers that are currently available. In
other embodiments, the ABS filament is made out of oil based
resources, has a much higher melting point than PLA plastic, and is
stronger and harder. In other embodiments, the PLA filament is a
biodegradable type of plastic that is manufactured out of
plant-based resources, such as cornstarch or sugar cane. Other
materials may include, but are not limited to polyvinyl acetate
(PVA), nylon, thermoplastic elastomer (TPE), polycarbonate (PC),
polyethylene terephthalate (PET), high impact polystyrene (HIPS),
flexible material, stone filament, wood filament, or a conductive
ABS filament. Additionally, bronze fill, wood fill, and conductive
fill are within the scope of materials from which the materials may
be constructed. In other embodiments, both types of thermoplastics
or any other suitable polymer build material could be used to print
multi-colored 3D objects depending on the needs of the user and the
intentions of the final 3D object. Furthermore, material
development is an ever-evolving aspect of 3D printing, and,
therefore, the filament may be constructed from materials that are
not yet known. Additionally, additives may be added to the
filaments. Additives include, but are not limited to, color,
conductive materials, magnetic materials, antimicrobial materials,
metals, adhesives, and flavoring.
[0088] The color described herein may be solvent dyes, inks,
pigments, and/or any other suitable chemical compositions or
additives, such as aromatics, anti-microbial substances,
flavorings, conductive materials, magnetic materials, glitters,
fluorescent materials, and living cells. In preferred embodiments,
the color-application unit 104 will use a solvent dye as the
applied composition for adding color to the filament portions 144,
504, 508. The dyes may be composed of xylene, ethyl acetate, ethyl
lactate, ethanol, butanol, and acetone, or any combination thereof.
Alternatively, other organic dyes, pigments, and/or inks could be
used to integrate color into the filament portions 144, 504, 508.
These listed compositions are intended as examples of possible
applied compositions and are not intended to be exclusive.
[0089] A composition the solvent of the color is determined by
solubility parameters of solvents and materials used for the
filaments and filament portions thereof. An effective solvent will
have a solubility parameter of about 2 (cal/cm.sup.3).sup.0.5
within the plastic material to be solubilized or penetrated. For
example, PLA has a solubility parameter of 10.3
(cal/cm.sup.3).sup.0.5 and xylene, ethyl lactate and ethyl acetate
have solubility parameters of 8.8 (cal/cm.sup.3).sup.0.5, 10.41
(cal/cm.sup.3).sup.0.5, and 9.1 (cal/cm.sup.3).sup.0.5,
respectively.
[0090] Referring back to FIG. 1, each of the color-application and
feed assemblies 100, 500 illustrated and described herein also
includes a controller 700, a power supply module 704, a user
interface 708, a communication module 712, and a motor module
716.
[0091] The controller or processor 700 is part of, or is connected
to, an external device (e.g., a computer). The controller 700 (or
computer) includes combinations of software and hardware that are
operable to, among other functions, control the operation of
color-application and feed assembly 100, 500, control the speed at
which the filament portions 144, 188, 192, 504, 508 are pulled from
the spools 148, 180, 184, 520, 524, and control the color that is
applied to the filament portions 144, 504, 508. In one
implementation, the controller 700 or external device includes a
printed circuit board ("PCB") that is populated with a plurality of
electrical and electronic components that provide, power,
operational control, and protection to the power distribution
devices. In some implementations, the PCB includes, for example, a
processing unit (e.g., a microprocessor, a microcontroller, or
another suitable programmable device), a memory, and a bus. The bus
connects various components of the PCB including the memory to the
processing unit. The memory includes, for example, a read-only
memory ("ROM"), a random access memory ("RAM"), an electrically
erasable programmable read-only memory ("EEPROM"), a flash memory,
a hard disk, or another suitable magnetic, optical, physical, or
electronic memory device. The processing unit is connected to the
memory and executes software that is capable of being stored in the
RAM (e.g., during execution), the ROM (e.g., on a generally
permanent basis), or another non-transitory computer readable
medium such as another memory or a disc. Additionally or
alternatively, the memory is included in the processing unit. The
controller also includes an input/output ("I/O") unit that includes
routines for transferring information between components within the
controller and other components of the color-application assembly
or the 3D printer. For example, the communication module is
configured to provide communication between the color-application
and feed assembly and one or more devices in the 3D printer.
[0092] Software included in some implementations of the power
distribution device is stored in the memory of the controller 700.
The software includes, for example, firmware, one or more
applications, program data, one or more program modules, and other
executable instructions. The controller 700 is configured to
retrieve from memory and execute, among other components,
instructions related to the control processes and methods described
above. For example, the controller 700 is configured to execute
instructions retrieved from the memory for determining which color
to apply to the filament portions 144, 504, 508 based on data
received in data packets from an external source or from the
memory. In some implementations, the controller 700 or external
device includes additional, fewer, or different components. In some
embodiments, a computer program may be utilized to assist in the
performance of the present technology. For example, using a
computer program in conjunction with the 3D printer 10, the user
imports a model of the desired 3D object into the program. The user
then indicates the desired color or colors on the computer model.
The computer program then slices the colored model layer by layer,
creating directions for which color or colors to apply and when,
and sends those directions to the color-application unit 104.
[0093] The PCB also includes, among other components, a plurality
of additional passive and active components such as resistors,
capacitors, inductors, integrated circuits, and amplifiers. These
components are arranged and connected to provide a plurality of
electrical functions to the PCB including, among other things,
filtering, signal conditioning, or voltage regulation. For
descriptive purposes, the PCB and the electrical components
populated on the PCB are collectively referred to as the controller
700.
[0094] The power supply module 704 supplies a nominal AC or DC
voltage to the color-application and feed assembly 100, 500. The
power supply module 704 is powered by main power having nominal
line voltages between, for example, 100V and 240V AC and
frequencies of approximately 50-60 Hz. The power supply module 704
is also configured to supply lower voltages to operate circuits and
components within the color-application and feed assembly 100, 500.
In some implementations, the power distribution device is powered
by one or more batteries or battery packs.
[0095] The user interface 708 is included to control the
color-application and feed assembly 100, 500 or the operation of
the 3D printer 10 as a whole. The user interface is operably
coupled to the controller to control, for example, the color
applied to the filament portions 144, 504, 508. The user interface
708 can include any combination of digital and analog input devices
required to achieve a desired level of control for the system. For
example, the user interface 708 can include a computer having a
display and input devices, a touch-screen display, a plurality of
knobs, dials, switches, buttons, faders, or the like. In some
implementations, the user interface is separated from the
color-application and feed assembly 100, 500.
[0096] The communication module 712 sends and/or receives signals
to and/or from one or more separate communication modules. Signals
include, among other components, information, data, serial data,
and data packets. The communication module 712 can be coupled to
one or more separate communication modules via wires, fiber, and/or
a wirelessly. Communication via wires and/or fiber can be any
appropriate network topology known to those skilled in the art,
such as Ethernet. Wireless communication can be any appropriate
wireless network topology known to those skilled in the art, such
as Wi-Fi.
[0097] The motor module 716 includes, among other components, one
or more motor devices. The one or more motor devices 164, 268, 528
are configured to receive signals from the controller 700 and pull
the filament portions 144, 188, 192, 504, 508 through the
color-application assembly. In some implementations, the one or
more motor devices are stepper motors.
[0098] The illustrated controller 700 is also coupled to the motor
assemblies 176 of the color applicators 156. In some
implementations, the controller 700 transmits signals to the motor
assemblies 176, which cause the assemblies 176 to move the color
applicators 156. For example, based on a desired color for a
particular layer or portion of a 3D printed object, the controller
700 can actuate the motor assemblies 176 at suitable times to color
the filament 290 so that portions of the filament 290 being used to
form the particular layer or portion are the proper color. Since
the controller 700, color-application unit 100, and 3D printer 10
function as a single system, the controller 700 knows how far the
colored filament 290 will travel before the filament 290 will
actually be used by the printer 10. The controller 700 accounts for
this lag time to appropriately color the filament 290. Furthermore,
the controller 700 can continuously actuate and de-actuate the
motor assemblies 176 to apply different colors to different
sections of the filament 290. For example, the controller 700 can
actuate the assemblies 176 to color a first section (e.g., 10 cm
length) of the filament 290 a first color (e.g., red), color a
second section (e.g., a 20 cm length) of the filament 290 a second
color (e.g., blue), and color a third section (e.g., a 15 cm
length) of the filament 290 a third color (e.g., white). The amount
and type of color applied to the filament 290 can be programmed
into the controller 700 by a user, or can be automatically
determined by the controller 700 based on desired colors identified
in, for example, a CAD model.
[0099] Although the devices, systems, and methods discussed above
are primarily described as being disposed upstream of a
three-dimensional printer, implementations can include devices,
systems, and methods where color is applied to an extrudate within
a three-dimensional printer (e.g., a color-application unit is
integral with the three-dimensional printer). To this end, a
three-dimensional printer will now be discussed with reference to
FIG. 25, where the three-dimensional printer can be adapted to be
integrated with the devices, systems, and methods discussed above
for coloring a filament of build material before extruding the
filament to create a colored object during a three-dimensional
printing process.
[0100] FIG. 25 is a block diagram of a three-dimensional printer.
In general, the printer 2500 may include a build platform 2502, a
conveyor 2504, an extruder 2506, an x-y-z positioning assembly
2508, and a controller 2510 that cooperate to fabricate an object
2512 within a working volume 2514 of the printer 2500.
[0101] The build platform 2502 may include a surface 2516 that is
rigid and substantially planar. The surface 2516 may support the
conveyer 2504 in order to provide a fixed, dimensionally and
positionally stable platform on which to build the object 2512.
[0102] The build platform 2502 may include a thermal element 2530
that controls the temperature of the build platform 2502 through
one or more active devices 2532 such as resistive elements that
convert electrical current into heat, Peltier effect devices that
can create a heating or cooling affect, or any other thermoelectric
heating and/or cooling devices. Thus the thermal element 2530 may
be a heater that provides active heating to the build platform
2502, a cooling element that provides active cooling to the build
platform 2502, or a combination of these. The heater 2530 may be
coupled in a communicating relationship with the controller 2510 in
order for the controller 2510 to controllably impart heat to or
remove heat from the surface 2516 of the build platform 2502. Thus,
the thermal element 2530 may include an active cooling element
positioned within or adjacent to the build platform 2502 to
controllably cool the build platform 2502.
[0103] It will be understood that a variety of other techniques may
be employed to control a temperature of the build platform 2502.
For example, the build platform 2502 may use a gas cooling or gas
heating device such as a vacuum chamber or the like in an interior
thereof, which may be quickly pressurized to heat the build
platform 2502 or vacated to cool the build platform 2502 as
desired. As another example, a stream of heated or cooled gas may
be applied directly to the build platform 2502 before, during,
and/or after a build process. Any device or combination of devices
suitable for controlling a temperature of the build platform 2502
may be adapted to use as the thermal element 2530 described
herein.
[0104] The conveyer 2504 may be formed of a sheet 2518 of material
that moves in a path 2520 through the working volume 2514. Within
the working volume 2514, the path 2520 may pass proximal to the
surface 2516 of the build platform 2502--that is, resting directly
on or otherwise supported by the surface 2516--in order to provide
a rigid, positionally stable working surface for a build. It will
be understood that while the path 2520 is depicted as a
unidirectional arrow, the path 2520 may be bidirectional, such that
the conveyer 2504 can move in either of two opposing directions
through the working volume 2514. It will also be understood that
the path 2520 may curve in any of a variety of ways, such as by
looping underneath and around the build platform 2502, over and/or
under rollers, or around delivery and take up spools for the sheet
2518 of material. Thus, while the path 2520 may be generally (but
not necessarily) uniform through the working volume 2514, the
conveyer 2504 may move in any direction suitable for moving
completed items from the working volume 2514. The conveyor may
include a motor or other similar drive mechanism (not shown)
coupled to the controller 2510 to control movement of the sheet
2518 of material along the path 2520. Various drive mechanisms are
described in further detail below.
[0105] In general, the sheet 2518 may be formed of a flexible
material such as a mesh material, a polyamide, a polyethylene
terephthalate (commercially available in bi-axial form as MYLAR), a
polyimide film (commercially available as KAPTON), or any other
suitably strong polymer or other material. The sheet 2518 may have
a thickness of about three to about seven thousandths of an inch,
or any other thickness that permits the sheet 2518 to follow the
path 2520 of the conveyer 2504. For example, with sufficiently
strong material, the sheet 2518 may have a thickness of about one
to about three thousandths of an inch. The sheet 2518 may instead
be formed of sections of rigid material joined by flexible
links.
[0106] A working surface of the sheet 2518 (e.g., an area on the
top surface of the sheet 2518 within the working volume 2514) may
be treated in a variety of manners to assist with adhesion of build
material to the surface 2518 and/or removal of completed objects
from the surface 2518. For example, the working surface may be
abraded or otherwise textured (e.g., with grooves, protrusions, and
the like) to improve adhesion between the working surface and the
build material.
[0107] A variety of chemical treatments may be used on the working
surface of the sheet 2518 of material to further facilitate build
processes as described herein. For example, the chemical treatment
may include a deposition of material that can be chemically removed
from the conveyer 2504 by use of water, solvents, or the like. This
may facilitate separation of a completed object from the conveyer
by dissolving the layer of chemical treatment between the object
2512 and the conveyor 2504. The chemical treatments may include
deposition of a material that easily separates from the conveyer
such as a wax, mild adhesive, or the like. The chemical treatment
may include a detachable surface such as an adhesive that is
sprayed on to the conveyer 2504 prior to fabrication of the object
2512.
[0108] In one aspect, the conveyer 2504 may be formed of a sheet of
disposable, one-use material that is fed from a dispenser and
consumed with each successive build.
[0109] In one aspect, the conveyer 2504 may include a number of
different working areas with different surface treatments adapted
for different build materials or processes. For example, different
areas may have different textures (smooth, abraded, grooved, etc.).
Different areas may be formed of different materials. Different
areas may also have or receive different chemical treatments. Thus
a single conveyer 2504 may be used in a variety of different build
processes by selecting the various working areas as needed or
desired.
[0110] The extruder 2506 may include a chamber 2522 in an interior
thereof to receive a build material. The build material may, for
example, include acrylonitrile butadiene styrene ("ABS"),
high-density polyethylene ("HDPL"), polylactic acid, or any other
suitable plastic, thermoplastic, or other material that can
usefully be extruded to form a three-dimensional object. The
extruder 2506 may include an extrusion tip 2524 or other opening
that includes an exit port with a circular, oval, slotted or other
cross-sectional profile that extrudes build material in a desired
cross-sectional shape.
[0111] The extruder 2506 may include a heater 2526 to melt
thermoplastic or other meltable build materials within the chamber
2522 for extrusion through an extrusion tip 2524 in liquid form.
While illustrated in block form, it will be understood that the
heater 2526 may include, e.g., coils of resistive wire wrapped
about the extruder 2506, one or more heating blocks with resistive
elements to heat the extruder 2506 with applied current, an
inductive heater, or any other arrangement of heaters suitable for
creating heat within the chamber 2522 to melt the build material
for extrusion. The extruder 2506 may also or instead include a
drive assembly 2528 including a motor or the like to push the build
material into the chamber 2522 and/or through the extrusion tip
2524. In another implementation, the drive assembly 2528 may be
separate and independent from the extruder 2506, but still enables
movement of the build material in the printer 2500, e.g., between
components of the printer 2500 and/or for extrusion through the
extruder 2506. In an aspect, the drive assembly 2528 moves a
filament of build material from a coloring system 2540 to the
extruder 2506 for depositing colored build material in the
three-dimensional printing process.
[0112] In general operation (and by way of example rather than
limitation), a build material such as ABS plastic in filament form
may be fed into the chamber 2522 from a spool or the like by the
drive assembly 2528, melted by the heater 2526, and extruded from
the extrusion tip 2524. By controlling a rate of the drive assembly
2528 (e.g., a motor thereof), the temperature of the heater 2526,
and/or other process parameters, the build material may be extruded
at a controlled volumetric rate. It will be understood that a
variety of techniques may also or instead be employed to deliver
build material at a controlled volumetric rate, which may depend
upon the type of build material, the volumetric rate desired, and
any other factors. All such techniques that might be suitably
adapted to delivery of build material for fabrication of a
three-dimensional object are intended to fall within the scope of
this disclosure. Other techniques may be employed for
three-dimensional printing, including extrusion-based techniques
using a build material that is curable and/or a build material of
sufficient viscosity to retain shape after extrusion.
[0113] The x-y-z positioning assembly 2508 may generally be adapted
to three-dimensionally position the extruder 2506 and the extrusion
tip 2524 within the working volume 2514. Thus by controlling the
volumetric rate of delivery for the build material and the x, y, z
position of the extrusion tip 2524, the object 2512 may be
fabricated in three dimensions by depositing successive layers of
material in two-dimensional patterns derived, for example, from
cross-sections of a computer model or other computerized
representation of the object 2512. A variety of arrangements and
techniques are known in the art to achieve controlled linear
movement along one or more axes. The x-y-z positioning assembly
2508 may, for example, include a number of stepper motors 2509 to
independently control a position of the extruder within the working
volume along each of an x-axis, a y-axis, and a z-axis. More
generally, the x-y-z positioning assembly 2508 may include without
limitation various combinations of stepper motors, encoded DC
motors, gears, belts, pulleys, worm gears, threads, and the like.
Any such arrangement suitable for controllably positioning the
extruder 2506 within the working volume 2514 may be adapted to use
with the printer 2500 described herein.
[0114] By way of example and not limitation, the conveyor 2504 may
be affixed to a bed that provides x-y positioning within the plane
of the conveyor 2504, while the extruder 2506 can be independently
moved along a z-axis. As another example, the extruder 2506 may be
stationary while the conveyor 2504 is x, y, and z positionable. As
another example, the extruder 2506 may be x, y, and z positionable
while the conveyer 2504 remains fixed (relative to the working
volume 2514). In yet another example, the conveyer 2504 may, by
movement of the sheet 2518 of material, control movement in one
axis (e.g., the y-axis), while the extruder 2506 moves in the
z-axis as well as one axis in the plane of the sheet 2518. Thus in
one aspect, the conveyor 2504 may be attached to and move with at
least one of an x-axis stage (that controls movement along the
x-axis), a y-axis stage (that controls movement along a y-axis),
and a z-axis stage (that controls movement along a z-axis) of the
x-y-z positioning assembly 2508. More generally, any arrangement of
motors and other hardware controllable by the controller 2510 may
serve as the x-y-z positioning assembly 2508 in the printer 2500
described herein. Still more generally, while an x, y, z coordinate
system serves as a convenient basis for positioning within three
dimensions, any other coordinate system or combination of
coordinate systems may also or instead be employed, such as a
positional controller and assembly that operates according to
cylindrical or spherical coordinates.
[0115] The controller 2510 may be electrically coupled in a
communicating relationship with the build platform 2502, the
conveyer 2504, the x-y-z positioning assembly 2508, and the other
various components of the printer 2500. In general, the controller
2510 is operable to control the components of the printer 2500,
such as the build platform 2502, the conveyer 2504, the x-y-z
positioning assembly 2508, and any other components of the printer
2500 described herein to fabricate the object 2512 from the build
material. The controller 2510 may include any combination of
software and/or processing circuitry suitable for controlling the
various components of the printer 2500 described herein including
without limitation microprocessors, microcontrollers,
application-specific integrated circuits, programmable gate arrays,
and any other digital and/or analog components, as well as
combinations of the foregoing, along with inputs and outputs for
transceiving control signals, drive signals, power signals, sensor
signals, and the like. In one aspect, the controller 2510 may
include a microprocessor or other processing circuitry with
sufficient computational power to provide related functions such as
executing an operating system, providing a graphical user interface
(e.g., to a display coupled to the controller 2510 or printer
2500), convert three-dimensional models into tool instructions, and
operate a web server or otherwise host remote users and/or activity
through the network interface 2536 described below.
[0116] A variety of additional sensors may be usefully incorporated
into the printer 2500 described above. These are generically
depicted as sensor 2534 in FIG. 25, for which the positioning and
mechanical/electrical interconnections with other elements of the
printer 2500 will depend upon the type and purpose of the sensor
2534 and will be readily understood and appreciated by one of
ordinary skill in the art. The sensor 2534 may include a
temperature sensor positioned to sense a temperature of the surface
of the build platform 2502. This may, for example, include a
thermistor or the like embedded within or attached below the
surface of the build platform 2502. This may also or instead
include an infrared detector or the like directed at the surface
2516 of the build platform 2502 or the sheet 2518 of material of
the conveyer 2504. Other sensors that may be usefully incorporated
into the printer 2500 as the sensor 2534 include a heat sensor, a
volume flow rate sensor, a weight sensor, a sound sensor, and a
light sensor. Certain more specific examples are provided below by
way of example and not of limitation.
[0117] The sensor 2534 may include a sensor to detect a presence
(or absence) of the object 2512 at a predetermined location on the
conveyer 2504. This may include an optical detector arranged in a
beam-breaking configuration to sense the presence of the object
2512 at a location such as an end of the conveyer 2504. This may
also or instead include an imaging device and image processing
circuitry to capture an image of the working volume 2514 and
analyze the image to evaluate a position of the object 2512. This
sensor 2534 may be used for example to ensure that the object 2512
is removed from the conveyor 2504 prior to beginning a new build at
that location on the working surface such as the surface 2516 of
the build platform 2502. Thus the sensor 2534 may be used to
determine whether an object is present that should not be, or to
detect when an object is absent. The feedback from this sensor 2534
may be used by the controller 2510 to issue processing interrupts
or otherwise control operation of the printer 2500.
[0118] The sensor 2534 may include a sensor that detects a position
of the conveyer 2504 along the path. This information may be
obtained from an encoder in a motor that drives the conveyer 2504,
or using any other suitable technique such as a visual sensor and
corresponding fiducials (e.g., visible patterns, holes, or areas
with opaque, specular, transparent, or otherwise detectable
marking) on the sheet 2518.
[0119] The sensor 2534 may include a heater (instead of or in
addition to the thermal element 2530) to heat the working volume
2514 such as a radiant heater or forced hot air to maintain the
object 2512 at a fixed, elevated temperature throughout a build.
The sensor 2534 may also or instead include a cooling element to
maintain the object 2512 at a predetermined sub-ambient temperature
throughout a build.
[0120] The sensor 2534 may also or instead include at least one
video camera. The video camera may generally capture images of the
working volume 2514, the object 2512, or any other hardware
associated with the printer 2500. The video camera may provide a
remote video feed through the network interface 2536, which feed
may be available to remote users through a user interface
maintained by, e.g., remote hardware, or within a web page provided
by a web server hosted by the three-dimensional printer 2500. Thus,
in one aspect there is a user interface adapted to present a video
feed from at least one video camera of a three-dimensional printer
to a remote user through a user interface.
[0121] The sensor 2534 may also or instead include more complex
sensing and processing systems or subsystems, such as a
three-dimensional scanner using optical techniques (e.g.,
stereoscopic imaging, or shape from motion imaging), structured
light techniques, or any other suitable sensing and processing
hardware that might extract three-dimensional information from the
working volume 2514. In another aspect, the sensor 2534 may include
a machine vision system that captures images and analyzes image
content to obtain information about the status of a job, working
volume 2514, or an object 2512 therein. The machine vision system
may support a variety of imaging-based automatic inspection,
process control, and/or robotic guidance functions for the
three-dimensional printer 2500 including without limitation
pass/fail decisions, error detection (and corresponding audible or
visual alerts), shape detection, position detection, orientation
detection, collision avoidance, and the like.
[0122] Other components, generically depicted as other hardware
2535, may also be included, such as input devices including a
keyboard, touchpad, mouse, switches, dials, buttons, motion
sensors, and the like, as well as output devices such as a display,
a speaker or other audio transducer, light emitting diodes, and the
like. Other hardware 2535 may also or instead include a variety of
cable connections and/or hardware adapters for connecting to, e.g.,
external computers, external hardware, external instrumentation or
data acquisition systems, and the like.
[0123] The printer 2500 may include, or be connected in a
communicating relationship with, a network interface 2536. The
network interface 2536 may include any combination of hardware and
software suitable for coupling the controller 2510 and other
components of the printer 2500 to a remote computer in a
communicating relationship through a data network. By way of
example and not limitation, this may include electronics for a
wired or wireless Ethernet connection operating according to the
IEEE 802.11 standard (or any variation thereof), or any other short
or long range wireless networking components or the like. This may
include hardware for short range data communications such as
Bluetooth or an infrared transceiver, which may be used to couple
into a local area network or the like that is in turn coupled to a
data network such as the Internet. This may also or instead include
hardware/software for a WiMax connection or a cellular network
connection (using, e.g., CDMA, GSM, LTE, or any other suitable
protocol or combination of protocols). Consistently, the controller
2510 may be configured to control participation by the printer 2500
in any network to which the network interface 2536 is connected,
such as by autonomously connecting to the network to retrieve
printable content, or responding to a remote request for status or
availability.
[0124] Devices, systems, and methods for enabling color control in
three-dimensional printing processes by adding dye to a filament of
build material may be integrated with the printer 2500 described
above, such as with a coloring system 2540 that colors the interior
of a filament upstream of the extruder 2506. The coloring system
2540 may include hardware such as the color-application unit and
coupler described above.
[0125] The extruder 2506 may be configured to deposit a build
material in a three-dimensional printing process. The extruder 2506
may be any as described herein or otherwise known in the art. For
example, the extruder 2506 may be disposed in a printer head of the
three-dimensional printer 2500. The coloring system 2540 (e.g.,
including the color application unit and coupler) may in general be
disposed anywhere upstream from the extruder 2506, or more
specifically upstream from the chamber 2522 where build material is
liquefied for extrusion. The coloring system 2540 may include any
of the color-application units and other hardware described herein,
and the build material may correspondingly be a filament having any
of the cross-sections described above. The coloring system 2540 may
include a plurality of color applicators, where each is operable to
selectively apply a different color to the interior surface of the
filament. In another aspect, the color applicator includes an
inkjet cartridge or other device or system positioned and
configured to apply color by painting, inkjetting, or otherwise
applying a colorant to desired surfaces.
[0126] As described above, the coloring system 2540 may include a
body, a conduit extending through the body, and a motor that
engages the filament to move it through the conduit. The
color-application unit may also include a through-hole that extends
through the body and is communication with the conduit.
Additionally, the color applicator may include an elongate member
containing the color and having a color applicator tip that is
configured to apply the color to the interior surface of the
filament through the through-hole. In an aspect, at least a portion
of the elongate member is slidably received within the through-hole
to selectively engage and apply the color to the interior surface
of the filament.
[0127] The coupler may be configured to receive the filament from
the color applicator and to substantially enclose the interior
surface of the filament to which the color is applied. This may be
accomplished through, e.g., crimping the filament, sealing the
filament, connecting/joining multiple parts of a filament together,
and so on. The coupler may use a heater or the like to fuse
portions of the filament for substantially enclosing its interior
surface. The coupler may also or instead mechanically join portions
of the filament together to substantially enclose its interior
surface. In an aspect, the coupler is connected to the extruder
2506 by a conduit, where the conduit includes a pathway for the
filament to travel between the coupler and the extruder 2506. More
generally, the coloring system 2540 may be adapted for use with the
printer 2500, and in particular for integration into the feedpath
of the printer 2500, e.g., at a location proximal to the extruder
2506 in order to reduce latency for color switches.
[0128] As generally described above, the filament may include a
first filament portion and a second filament portion, where at
least one of the first filament portion and the second filament
portion include the interior surface that is colored by the color
applicator. The coupler may be configured to join the first
filament portion to the second filament portion to form the
filament for extrusion in the three-dimensional printing process.
The coupler may include a body that has a first channel and a
second channel, where the first channel receives the first filament
portion and the second channel receives the second filament
portion. The first channel and the second channel may converge
within the body to form a discharge channel that guides the
filament through the body. The coupler may further include a motor
and a roller assembly that is actuated by the motor. The roller
assembly may engage the first filament portion and the second
filament portion to advance the filament through the body.
[0129] It will be understood that the coupler may be omitted in an
implementation. This includes an implementation with a single-piece
filament or a multi-piece filament. In other words, the filament
may be colored and then directed to the extruder for extrusion
without being coupled in any manner.
[0130] In an aspect, the extruder 2506 and the coloring system 2540
are disposed within a build volume of the three-dimensional printer
2500, or attached to a positioning system capable of positioning
the extruder 2506 and coloring system 2540 so that a tip of the
extruder 2506 can deposit material at a desired location within the
build volume under control of the controller.
[0131] In an implementation, the color-application unit and the
coupler of the coloring system 2540 may be integrated together as a
single hardware unit mechanically fixed to the extruder 2506. In
another implementation, the extruder 2506 and the coupler may be
integrated together as a single unit. In yet another
implementation, the color-application unit and the extruder 2506
may be integrated together, e.g., in a print head or the like of
the printer 2500. Still more generally, the coloring system 2540
may be integrated into the printer 2500 in a variety of manners,
e.g., coupled to the extruder 2506 or a frame of the printer 2500,
or at some other position along the feedpath of a filament or
similar build material.
[0132] FIG. 26 is a flowchart of a method for three-dimensional
fabrication of an object using a three-dimensional printer.
[0133] As shown in step 2602, the method 2600 may include receiving
a filament at a color-application unit of the three-dimensional
printer. The color-application unit may be positioned upstream of
an extruder within the three-dimensional printer, or more
specifically upstream of a chamber of the extruder where the
filament is liquefied for extrusion.
[0134] As shown in step 2604, the method 2600 may include applying
color to an interior surface of the filament using a color
applicator coupled to the color-application unit. This may, for
example, be any of the color applicators described above, as well
as combinations of color applicators for a broader spectrum of
controllable colors.
[0135] As shown in step 2606, the method 2600 may include coupling
the filament. For example, the filament may include a first
filament portion and a second filament portion, where at least one
of the first filament portion and the second filament portion
include the interior surface to be colored by the color applicator.
Thus, coupling the filament may include coupling the first filament
portion to the second filament portion to form the filament for
extrusion. In an aspect, a coupler that is positioned downstream of
the color applicator and upstream of the extruder couples the first
filament portion and the second filament portion. In another
aspect, the extruder couples the first filament portion and the
second filament portion.
[0136] In an embodiment including a coupler, coupling the filament
may include receiving the first filament portion in a first channel
disposed in a body of the coupler, receiving the second filament
portion in a second channel disposed in the body of the coupler,
and joining the first filament portion and the second filament
portion within a discharge channel formed by a convergence of the
first channel and the second channel within the body of the
coupler.
[0137] As shown in step 2608, the method 2600 may include directing
the filament from the color-application unit to the extruder.
[0138] As shown in step 2610, the method 2600 may include extruding
the filament to fabricate the object in a three-dimensional
printing process, as generally contemplated above.
[0139] The coloring system as described herein may be included in a
device configured for placement in a three-dimensional printer,
i.e., upstream from an extruder. For example, in an aspect, the
device includes a color-application unit configured to receive a
filament of build material, where the color application unit is
configured for placement upstream of an extruder, e.g., it is a
modular component or the like. A color applicator may be coupled to
the color-application unit and operable to selectively apply a
color to an interior surface of the filament before the filament is
passed to the extruder.
[0140] The above systems, devices, methods, processes, and the like
may be realized in hardware, software, or any combination of these
suitable for the control, data acquisition, and data processing
described herein. This includes realization in one or more
microprocessors, microcontrollers, embedded microcontrollers,
programmable digital signal processors or other programmable
devices or processing circuitry, along with internal and/or
external memory. This may also, or instead, include one or more
application specific integrated circuits, programmable gate arrays,
programmable array logic components, or any other device or devices
that may be configured to process electronic signals. It will
further be appreciated that a realization of the processes or
devices described above may include computer-executable code
created using a structured programming language such as C, an
object oriented programming language such as C++, or any other
high-level or low-level programming language (including assembly
languages, hardware description languages, and database programming
languages and technologies) that may be stored, compiled or
interpreted to run on one of the above devices, as well as
heterogeneous combinations of processors, processor architectures,
or combinations of different hardware and software. At the same
time, processing may be distributed across devices such as the
various systems described above, or all of the functionality may be
integrated into a dedicated, standalone device. All such
permutations and combinations are intended to fall within the scope
of the present disclosure.
[0141] Embodiments disclosed herein may include computer program
products comprising computer-executable code or computer-usable
code that, when executing on one or more computing devices,
performs any and/or all of the steps of the control systems
described above. The code may be stored in a non-transitory fashion
in a computer memory, which may be a memory from which the program
executes (such as random access memory associated with a
processor), or a storage device such as a disk drive, flash memory
or any other optical, electromagnetic, magnetic, infrared or other
device or combination of devices. In another aspect, any of the
control systems described above may be embodied in any suitable
transmission or propagation medium carrying computer-executable
code and/or any inputs or outputs from same.
[0142] It will be appreciated that the devices, systems, and
methods described above are set forth by way of example and not of
limitation. Numerous variations, additions, omissions, and other
modifications will be apparent to one of ordinary skill in the art.
In addition, the order or presentation of method steps in the
description and drawings above is not intended to require this
order of performing the recited steps unless a particular order is
expressly required or otherwise clear from the context.
[0143] The method steps of the implementations described herein are
intended to include any suitable method of causing such method
steps to be performed, consistent with the patentability of the
following claims, unless a different meaning is expressly provided
or otherwise clear from the context. So for example performing the
step of X includes any suitable method for causing another party
such as a remote user, a remote processing resource (e.g., a server
or cloud computer) or a machine to perform the step of X.
Similarly, performing steps X, Y and Z may include any method of
directing or controlling any combination of such other individuals
or resources to perform steps X, Y and Z to obtain the benefit of
such steps. Thus method steps of the implementations described
herein are intended to include any suitable method of causing one
or more other parties or entities to perform the steps, consistent
with the patentability of the following claims, unless a different
meaning is expressly provided or otherwise clear from the context.
Such parties or entities need not be under the direction or control
of any other party or entity, and need not be located within a
particular jurisdiction.
[0144] It will be appreciated that the methods and systems
described above are set forth by way of example and not of
limitation. Numerous variations, additions, omissions, and other
modifications will be apparent to one of ordinary skill in the art.
In addition, the order or presentation of method steps in the
description and drawings above is not intended to require this
order of performing the recited steps unless a particular order is
expressly required or otherwise clear from the context. Thus, while
particular embodiments have been shown and described, it will be
apparent to those skilled in the art that various changes and
modifications in form and details may be made therein without
departing from the spirit and scope of this disclosure and are
intended to form a part of the invention as defined by the
following claims, which are to be interpreted in the broadest sense
allowable by law.
* * * * *