U.S. patent application number 15/959096 was filed with the patent office on 2018-10-25 for powder dispensing in binder jetting for additive manufacturing.
The applicant listed for this patent is Desktop Metal, Inc.. Invention is credited to Ricardo Fulop, Steven Garrant, Anastasios John Hart, Paul A. Hoisington, George Hudelson, Jonah Samuel Myerberg, Emanuel Michael Sachs, Brett Schuster, Keith Vaillancourt.
Application Number | 20180304358 15/959096 |
Document ID | / |
Family ID | 62117081 |
Filed Date | 2018-10-25 |
United States Patent
Application |
20180304358 |
Kind Code |
A1 |
Myerberg; Jonah Samuel ; et
al. |
October 25, 2018 |
POWDER DISPENSING IN BINDER JETTING FOR ADDITIVE MANUFACTURING
Abstract
The devices, systems, and methods of the present disclosure are
directed to dispensing powder for rapid and accurate layer-by-layer
fabrication of three-dimensional objects formed through binder
jetting. More specifically, a powder may be dispensed from a hopper
movable over a volume defined by a powder box to facilitate, for
example, rapidly delivering powder in front of a spreader movable
across the volume to spread the powder into a layer. The hopper may
include a plurality of dispensing rollers along a dispensing region
of the hopper. The dispensing rollers may be rotatable relative to
one another to control dispensing the powder from the hopper to an
area in front of the spreader, reducing wasted motion associated
with moving a spreader to retrieve powder from a stationary powder
supply and reducing the likelihood of inadvertently delivering
powder from the hopper to unintended areas.
Inventors: |
Myerberg; Jonah Samuel;
(Lexington, MA) ; Fulop; Ricardo; (Lexington,
MA) ; Hoisington; Paul A.; (Hanover, NH) ;
Sachs; Emanuel Michael; (Newton, MA) ; Hart;
Anastasios John; (Waban, MA) ; Vaillancourt;
Keith; (Hudson, NH) ; Garrant; Steven; (Mont
Vernon, NH) ; Schuster; Brett; (Hollis, NH) ;
Hudelson; George; (Billerica, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Desktop Metal, Inc. |
Burlington |
MA |
US |
|
|
Family ID: |
62117081 |
Appl. No.: |
15/959096 |
Filed: |
April 20, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62488461 |
Apr 21, 2017 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B22F 1/0059 20130101;
B33Y 40/00 20141201; B33Y 10/00 20141201; B22F 3/16 20130101; B22F
3/004 20130101; B29C 64/165 20170801; B22F 3/008 20130101; B22F
2202/01 20130101; B22F 1/0081 20130101; B22F 2003/1056 20130101;
B22F 2998/00 20130101; B22F 2202/11 20130101; B22F 2999/00
20130101; B33Y 30/00 20141201; B22F 3/003 20130101; B22F 3/18
20130101 |
International
Class: |
B22F 3/00 20060101
B22F003/00; B22F 1/00 20060101 B22F001/00; B33Y 10/00 20060101
B33Y010/00; B33Y 30/00 20060101 B33Y030/00 |
Claims
1. An additive manufacturing system comprising: a print box
defining a volume; a print carriage movable over the volume, the
print carriage defining at least one ejection orifice directed
toward the volume as the print carriage moves over the volume; a
spreader movable over the volume in advance of the print carriage;
and a hopper movable over the volume in advance of the spreader,
the hopper defining a dispensing region, the hopper including a
plurality of dispensing rollers along the dispensing region, and
the plurality of dispensing rollers rotatable relative to one
another to move a powder through the dispensing region and toward
the volume in advance of the spreader as the spreader moves toward
a position over the volume to form a layer of the powder, onto
which a binder is deliverable from the at least one ejection
orifice of the print carriage trailing the spreader over the
volume.
2. The system of claim 1, wherein dispensing rollers of the
plurality of dispensing rollers are spaced apart from one another
to define a gap, and the plurality of dispensing rollers are
rotatable relative to one another to move the powder through the
gap and toward the volume.
3. The system of claim 2, wherein the dispensing region of the
hopper spans a dimension of the volume substantially parallel to
the gap as the hopper moves over the volume.
4. The system of claim 3, wherein the plurality of dispensing
rollers span the dimension of the volume as the hopper moves over
the volume.
5. The system of claim 1, wherein each dispensing roller of the
plurality of dispensing rollers has a substantially similar
diameter.
6. The system of claim 1, further comprising at least one motor
mechanically coupled to one or more dispensing rollers of the
plurality of dispensing rollers, the at least one motor actuatable
to rotate the plurality of dispensing rollers relative to one
another.
7. The system of claim 6, wherein the at least one motor is
actuatable to rotate the plurality of dispensing rollers in a
counter-rotating direction relative to one another.
8. The system of claim 6, further comprising a controller in
electrical communication with the at least one motor, the
controller configured to actuate the at least one motor based on
movement of the hopper over the volume.
9. The system of claim 8, wherein the controller is configured to
actuate the at least one motor in a first direction of movement of
the hopper over the volume and to pause actuation of the at least
one motor in a second direction of movement of the hopper over the
volume, the second direction of movement different from the first
direction of movement.
10. The system of claim 8, wherein the controller is configured to
actuate the at least one motor based on speed of movement of the
hopper over the volume.
11. The system of claim 8, wherein the controller is configured to
actuate the at least one motor to rotate the plurality of
dispensing rollers at substantially the same rotation speed.
12. The system of claim 6, wherein the hopper includes a storage
region in fluid communication with the dispensing region, the
powder movable from the storage region toward the dispensing region
through force of gravity as the hopper moves over the volume.
13. The system of claim 6, wherein the hopper includes a shutter
selectively movable between a first position away from the
dispensing region to a second position below the dispensing region
to interrupt movement of powder exiting the hopper via the
dispensing region.
14. The system of claim 13, wherein the shutter is selectively
movable between the first position and the second position based on
rotation of dispensing rollers of the plurality of dispensing
rollers.
15. A method of additive manufacturing of an object, the method
comprising: moving a hopper over a volume defined by a print box;
as the hopper moves over the volume, rotating a plurality of
dispensing rollers disposed along a dispensing region defined by
the hopper, the rotation of the plurality of dispensing rollers
moving a powder toward the volume from the dispensing region;
spreading the powder along the volume to form a layer of the
powder; and in a controlled two-dimensional pattern, ejecting a
binder from at least one ejection orifice of a print carriage to
the layer of the powder to form a portion of the object.
16. The method of claim 15, wherein rotation of the plurality of
dispensing rollers moves the powder toward the volume through a gap
defined between the plurality of dispensing rollers.
17. The method of claim 16, wherein the gap and the dispensing
region span a dimension of the volume substantially perpendicular
to a direction of movement of the hopper over the volume.
18. The method of claim 15, wherein rotating the plurality of
dispensing rollers includes counter-rotating dispensing rollers of
the plurality of dispensing rollers.
19. The method of claim 15, wherein rotating the plurality of
dispensing rollers includes controlling a rotation speed of at
least one dispensing roller of the plurality of dispensing rollers
based on a speed of movement of the hopper over the volume.
20. The method of claim 15, wherein rotating the plurality of
dispensing rollers includes controlling a rotation speed of at
least one dispensing roller of the plurality of dispensing rollers
based on position of the hopper over the volume.
21. The method of claim 20, wherein controlling the rotation speed
of the at least one dispensing roller includes reducing the
rotation speed of the at least one dispensing roller as the hopper
moves from a first side of the volume to a second side of the
volume, the second side of the volume opposite the first side of
the volume.
22. The method of claim 15, wherein rotating the plurality of
dispensing rollers includes rotating each dispensing roller of the
plurality of dispensing rollers at substantially the same rotation
speed.
23. The method of claim 15, wherein rotating the plurality of
dispensing rollers includes controlling a rotation speed of each
dispensing roller of the plurality of dispensing rollers based on a
direction of movement of the hopper over the volume.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Patent Applications No. 62/488,461, filed on Apr. 21, 2017, the
entire contents of which are incorporated herein by reference.
BACKGROUND
[0002] Binder jetting is an additive manufacturing technique based
on the use of a liquid binder to join particles of a powder to form
a three-dimensional object. In particular, a controlled pattern of
the liquid binder is applied to successive layers of the powder in
a powder bed such that the layers of the powder adhere to one
another form a three-dimensional object. The three-dimensional
object is then densified into a finished part through subsequent
processing, such as sintering.
[0003] The binder jetting fabrication process used to form the
three-dimensional objects, however, can present certain challenges
with respect to quality and throughput of finished parts formed
from the three-dimensional objects. In particular, consistent
layer-by-layer distribution of the powder and the liquid binder to
form the three-dimensional object is important for achieving target
quality of the finished part formed from the three-dimensional
object. However, the time associated with consistent layer-by-layer
distribution of the powder and the liquid binder can have an
adverse impact on the commercial scale viability of binder jetting
as an additive manufacturing technique to form finished parts.
Thus, there generally remains a need for improving speed in the
layer-by-layer distribution of the powder and liquid binder while
maintaining or improving quality of three-dimensional objects
formed using binder jetting techniques.
SUMMARY
[0004] The devices, systems, and methods of the present disclosure
are directed to dispensing powder for rapid and accurate
layer-by-layer fabrication of three-dimensional objects formed
through binder jetting. More specifically, a powder may be
dispensed from a hopper movable over a volume defined by a powder
box to facilitate, for example, rapidly delivering powder in front
of a spreader movable across the volume to spread the powder into a
layer. The hopper may include a plurality of dispensing rollers
along a dispensing region of the hopper. The dispensing rollers may
be rotatable relative to one another to control dispensing the
powder from the hopper to an area in front of the spreader,
reducing wasted motion associated with moving a spreader to
retrieve powder from a stationary powder supply and reducing the
likelihood of inadvertently delivering powder from the hopper to
unintended areas.
[0005] According to one aspect, an additive manufacturing system
may include a print box, a print carriage, a spreader, and a
hopper. The print box may define a volume, and the print carriage
may be movable over the volume, the print carriage defining at
least one ejection orifice directed toward the volume as the print
carriage moves over the volume. The spreader may be movable over
the volume in advance of the print carriage. The hopper may be
movable over the volume in advance of the spreader, the hopper
defining a dispensing region, the hopper including a plurality of
dispensing rollers along the dispensing region, and the plurality
of dispensing rollers rotatable relative to one another to move a
powder through the dispensing region and toward the volume in
advance of the spreader as the spreader moves toward a position
over the volume to form a layer of the powder, onto which a binder
is deliverable from the at least one ejection orifice of the print
carriage trailing the spreader over the volume. Each dispensing
roller of the plurality of dispensing rollers may have, for
example, a substantially similar diameter.
[0006] In certain implementations, dispensing rollers of the
plurality of dispensing rollers may be spaced apart from one
another to define a gap, and the plurality of dispensing rollers
are rotatable relative to one another to move the powder through
the gap and toward the volume. The dispensing region of the hopper
may span a dimension of the volume substantially parallel to the
gap as the hopper moves over the volume. Additionally, or
alternatively, the plurality of dispensing rollers may span the
dimension of the volume as the hopper moves over the volume.
[0007] In some implementations, the additive manufacturing system
may further include at least one motor mechanically coupled to one
or more dispensing rollers of the plurality of dispensing rollers,
the at least one motor actuatable to rotate the plurality of
dispensing rollers relative to one another. The at least one motor
may be, for example, actuatable to rotate the plurality of
dispensing rollers in a counter-rotating direction relative to one
another. In certain instances, the additive manufacturing system
may further include a controller in electrical communication with
the at least one motor, the controller configured to actuate the at
least one motor based on movement of the hopper over the volume.
The controller may be configured, for example, to actuate the at
least one motor in a first direction of movement of the hopper over
the volume and to pause actuation of the at least one motor in a
second direction of movement of the hopper over the volume, the
second direction of movement different from the first direction of
movement. Further, or instead, the controller may be configured to
actuate the at least one motor based on speed of movement of the
hopper over the volume. Additionally, or alternatively, the
controller may be configured to actuate the at least one motor to
rotate the plurality of dispensing rollers at substantially the
same rotation speed.
[0008] In certain implementations, the hopper may include a storage
region in fluid communication with the dispensing region, the
powder movable from the storage region toward the dispensing region
through force of gravity as the hopper moves over the volume.
[0009] In some implementations, the hopper may include a shutter
selectively movable between a first position away from the
dispensing region to a second position below the dispensing region
to interrupt movement of powder exiting the hopper via the
dispensing region. The shutter may be, for example, selectively
movable between the first position and the second position based on
rotation of dispensing rollers of the plurality of dispensing
rollers.
[0010] According to another aspect, a method of additive
manufacturing of an object may include moving a hopper over a
volume defined by a print box, as the hopper moves over the volume,
rotating a plurality of dispensing rollers disposed along a
dispensing region defined by the hopper, the rotation of the
plurality of dispensing rollers moving a powder toward the volume
from the dispensing region, spreading the powder along the volume
to form a layer of the powder, and, in a controlled two-dimensional
pattern, ejecting a binder from at least one ejection orifice of a
print carriage to the layer of the powder to form a portion of the
object.
[0011] In certain implementations, rotation of the plurality of
dispensing rollers may move the powder toward the volume through a
gap defined between the plurality of dispensing rollers. The gap
and the dispensing region may span a dimension of the volume
substantially perpendicular to a direction of movement of the
hopper over the volume. Additionally, or alternatively, rotating
the plurality of dispensing rollers may include counter-rotating
dispensing rollers of the plurality of dispensing rollers. Further
or instead, rotating the plurality of dispensing rollers may
include controlling a rotation speed of at least one dispensing
roller of the plurality of dispensing rollers based on a speed of
movement of the hopper over the volume. Still further or instead,
rotating the plurality of dispensing rollers may include
controlling a rotation speed of at least one dispensing roller of
the plurality of dispensing rollers based on position of the hopper
over the volume. For example, controlling the rotation speed of the
at least one dispensing roller may include reducing the rotation
speed of the at least one dispensing roller as the hopper moves
from a first side of the volume to a second side of the volume, the
second side of the volume opposite the first side of the
volume.
[0012] In some implementations, rotating the plurality of
dispensing rollers may include rotating each dispensing roller of
the plurality of dispensing rollers at substantially the same
rotation speed.
[0013] In certain implementations, rotating the plurality of
dispensing rollers may include controlling a rotation speed of each
dispensing roller of the plurality of dispensing rollers based on a
direction of movement of the hopper over the volume.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The devices, systems, and methods described herein are set
forth in the appended claims. However, for the purpose of
explanation, several implementations are set forth in the following
drawings:
[0015] FIG. 1A is a schematic representation of an additive
manufacturing system for forming a three-dimensional object.
[0016] FIG. 1B is a schematic representation of a material carriage
of the additive manufacturing system of FIG. 1A.
[0017] FIG. 2 is a bottom view of the print carriage of the
additive manufacturing system of FIG. 1A.
[0018] FIG. 3 is a flowchart of an exemplary method of thermal
energy delivery for additive manufacturing.
[0019] FIG. 4 is a flowchart of an exemplary method of dispensing
powder for additive manufacturing.
[0020] FIG. 5 is a flowchart of an exemplary method of packing
powder for additive manufacturing.
DESCRIPTION
[0021] Embodiments will now be described with reference to the
accompanying figures. The foregoing may, however, be embodied in
many different forms and should not be construed as limited to the
illustrated embodiments set forth herein.
[0022] 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 terms "or" and "and" should each
generally be understood to mean "and/or.".
[0023] 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 indicating a 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) provided herein, is intended merely to
better illuminate the embodiments and does not pose a limitation on
the scope of the embodiments. No language in the specification
should be construed as indicating any unclaimed element as
essential to the practice of the embodiments.
[0024] In the following description, it is understood that terms
such as "first," "second," "top," "bottom," "up," "down," and the
like, are words of convenience and are not to be construed as
limiting terms.
[0025] As used herein, the term two-dimensional slice should be
understood to refer to a cross-sectional segment of a
three-dimensional object, with the cross-sectional segment having a
small thickness (e.g., greater than about 40 microns and less than
about 150 microns) in a third dimension. That is, the thickness of
the two-dimensional slice may be substantially smaller than either
dimension of the cross-sectional segment in the other two
dimensions. In general, two-dimensional slices may be formed on top
of one another to form a three-dimensional object.
[0026] For the sake of clarity and completeness of explanation, the
description that follows describes the use of devices, systems, and
methods in the context of multi-directional binder jetting--that
is, binder jetting fabrication techniques in which layers of powder
are spread in at least two different directions in the course of
fabricating a three-dimensional object and, additionally or
alternatively, binder is applied to layers from a print carriage
moving over a volume in at least two different directions. However,
unless otherwise specified or made clear from the context, the
description of devices, systems, and methods with respect to
multi-directional binder jetting herein should not be understood to
preclude the use of such devices, systems, and methods in the
degenerate case of binder jetting along only a single direction.
Thus, for example, while devices, systems, and methods for
directing thermal energy, dispensing powder, and packing powder are
described herein with respect to multi-directional binder jetting,
such devices, systems, and methods should be understood to be
beneficially applicable to single-direction binder jetting, unless
otherwise indicated or made clear from the context.
[0027] Referring now to FIGS. 1A, 1B, and 2, an additive
manufacturing system 100 may include a print box 102, a first
material carriage 104a, a second material carriage 104b, and a
print carriage 106. The print box 102 may define a volume 108 in
which, as described in greater detail below, a three-dimensional
object 110 may be formed by jetting a binder 112 (e.g., a polymeric
binder) along layers of powder 120 (e.g., a powder including
inorganic particles, such as metal particles, ceramic particles, or
a combination thereof) spread in the volume 108. More specifically,
each instance of the first material carriage 104a and the second
material carriage 104b may include a respective instance of a
spreader 114 and a respective instance of a hopper 116. Each
instance of the spreader 114 may extend from the respective
instance of the first material carriage 104a and the second
material carriage 104b toward the volume 108 as the respective
material carriage moves over the volume 108 and, further or
instead, each instance of the hopper 116 may define a respective
instance of a dispensing region 118 directed toward the volume 108
to dispense a quantity of a powder 120 to the volume 108. The print
carriage 106 may define at least one ejection orifice 202
positioned to direct a fluid, such as the binder 112, toward the
powder 120 in the volume 108. As described in greater detail below,
the first material carriage 104a, the print carriage 106, and the
second material carriage 104b may each be movable over the volume
108 to carry out multi-directional binder jetting fabrication
according to any one or more of the methods described herein. In
general, such multi-directional binder jetting carried out by the
additive manufacturing system 100 may significantly increase the
rate of fabrication of three-dimensional objects, as compared to
binder jetting in only a single direction. As also described in
greater detail below, the additive manufacturing system 100 may
carry out any one or more of various different powder delivery,
powder spreading, thermal energy delivery techniques described
herein to address challenges associated with achieving quality
standards of the three-dimensional object 110 as the rate of
fabrication is increased through multi-directional printing.
[0028] In general, the spatial orientation of the first direction
and the second direction of movement of the first material carriage
104a, the second material carriage 104b, and the print carriage 106
relative to one another may be any of various different combination
of directions useful for achieving efficient movement of components
as two-dimensional slices of the three-dimensional object 110 are
formed in a layer-by-layer fabrication process. Thus, in a
particularly useful implementation, the first direction and the
second direction may be substantially opposite one another over the
volume 108 such that the components move back and forth over the
volume 108 as the three-dimensional object 110 is formed. As
compared to other directions of movement, this type of back and
forth movement may offer advantages associated with the rate of
fabrication. Further, or instead, back and forth movement may
reduce the complexity of controlling timing and position of the
first material carriage 104a, the second material carriage 104b,
and the print carriage 106 relative to one another and/or relative
to the volume 108, with corresponding advantages being realized in
accuracy of the three-dimensional object 110.
[0029] In certain implementations, the additive manufacturing
system 100 may include one or more rails 122, which may be useful
for controlling timing and positioning of one or more of the first
material carriage 104a, the second material carriage 104b, or the
print carriage 106 throughout multi-directional binder jetting to
form the three-dimensional object 110. For example, the first
material carriage 104a, the second material carriage 104b, the
print carriage 106, or a combination thereof, may be
bidirectionally movable along the one or more rails 122 to move
back and forth over the volume 108. As the respective components
undergo back and forth movement along the one or more rails 122, it
should be appreciated that the shape and position of the one or
more rails 122 relative to the volume 108 supports the first
material carriage 104a, the second material carriage 104b, the
print carriage 106, or a combination thereof, at one or more
controlled distances relative to the volume 108. As a specific
example, the one or more rails 122 may be substantially parallel to
the volume 108 at least along a portion of the one or more rails
122 corresponding to travel of the first material carriage 104a,
the second material carriage 104b, the print carriage 106, or a
combination thereof, over the volume 108. In certain instances, the
one or more rails 122 may be dimensioned to be substantially rigid
in response to forces exerted on the one or more rails 122 through
movement of the first material carriage 104a, the second material
carriage 104b, the print carriage, or a combination thereof, along
the one or more rails 122 such that the one or more controlled
distances are substantially maintained throughout the movement of
the respective components along the one or more rails 122.
Additionally, or alternatively, in instances in which the first
material carriage 104a, the second material carriage 104b, and the
print carriage 106 are movable on the same one or more rails 122,
the one or more rails 122 may advantageously provide a robust
mechanism for maintaining the components in a fixed physical
orientation relative to one another as the components move back and
forth over the volume 108.
[0030] In general, the timing of the respective movements the first
material carriage 104a, the second material carriage 104b, and the
print carriage 106 may be controlled according to any of various
different techniques suitable for achieving accurate and rapid
formation of the three-dimensional object 110 through
multi-directional binder jetting. Thus, in some implementations,
one or more of the first material carriage 104a, the second
material carriage 104b, and the print carriage 106 may be
independently movable relative to one another over the volume 108
in the first direction and in the second direction. Such
independent movement may be useful, for example, for reducing the
likelihood of contaminating or otherwise degrading performance of
the print carriage 106 through exposure to the powder 120 being
dispensed from the first material carriage 104a in the first
direction and from the second material carriage 104b in the second
direction. As an example, one or more of the first material
carriage 104a, the print carriage 106, and the second material
carriage 104b may be movable over the volume 108 one at a time as
the other components are disposed along one or more sides of the
volume 108. Additionally, or alternatively, one or more of the
first material carriage 104a, the second material carriage 104b,
and the print carriage 106 may be mechanically coupled to at least
another one of the first material carriage 104a, the second
material carriage 104b, and the print carriage 106 to move as a
single unit in the first direction and the second direction over
the volume 108. That is, while the first material carriage 104a,
the second material carriage 104b, and the print carriage 106 are
described and depicted as separate components, any one or more of
the features of the first material carriage 104a, the second
material carriage 104b, and the print carriage 106 may be combined
into a single unit. As compared to moving each component over the
volume 108 one at a time, such a single unit may advantageously
reduce delays and control complexity that may be associated with
moving the first material carriage 104a, the second material
carriage 104b, and the print carriage 106 bidirectionally across
the volume 108.
[0031] In general, the first material carriage 104a and the second
material carriage 104b may be substantially identical to one
another, except that each is generally a mirror configuration of
the other with respect to at least one plane extending through the
print carriage 106. This symmetry of the first material carriage
104a and the second material carriage 104b may be particularly
advantageous for achieving substantially similar layer
characteristics in each direction of the binder jetting process
carried out by the additive manufacturing system 100. In turn, such
similar layer characteristics may facilitate forming the
three-dimensional object 110 within target dimensional tolerances.
That is, the three-dimensional object 110 may be formed
substantially without defects associated with changing direction of
the layer-by-layer fabrication process. Accordingly, for the sake
of clarity and efficient description, the features of the first
material carriage 104a are described below and, unless another
intention is indicated, corresponding aspects of the second
material carriage 104b shall be understood to be identical to those
of the first material carriage 104a and are not described
separately.
[0032] The hopper 116 may define a storage region 124 in fluid
communication with the dispensing region 118 such that the powder
120 is movable (e.g., through the force of gravity, through the use
of actuators, or a combination thereof) from the storage region 124
to the volume 108 via the dispensing region 118. The storage region
124 may store, for example, a quantity of the powder 120 sufficient
for forming multiple layers of the three-dimensional object 110. As
a competing consideration, however, the capacity of the storage
region 124 may be limited by space and weight considerations
associated with rapid movement of the hopper 116 in some
applications.
[0033] To facilitate management of moisture in the quantity of the
powder 120 stored in the storage region 124, each of the first
material carriage 104a and the second material carriage 104b may
include a heater 126 in thermal communication with the storage
region 124 of the hopper 116. The heater 126 may be any of various
different types of heaters known in the art and, thus, may include
a resistance heater. In some instances, the heater 126 may be
adjustable to maintain the powder 120 in the storage region 124 at
a predetermined temperature, such as a predetermined temperature
provided by an operator of the machine.
[0034] Additionally, or alternatively, to facilitate management of
settling of the powder 120 stored in the storage region 124, each
of the first material carriage 104a and the second material
carriage 104b may include an agitator 128 in mechanical
communication with the storage region 124 of the hopper 116. In
general, the agitator 128 may vibrate walls of the storage region
124 at frequencies that are useful for reducing the likelihood of
the powder 120 sticking to the walls of the storage region 124
while not interfering with overall movement of the hopper 116
across the volume 108. By way of example, the agitator 128 may
include a piezoelectric element actuatable to vibrate the storage
region 124.
[0035] The dispensing region 118 of the hopper 116 may span a width
of the volume 108. As used in this context, the width of the volume
108 may include, for example, a dimension of the volume 108
substantially perpendicular to the first direction and the second
direction as the dispensing region 118 moves back and forth over
the volume 108 in the first direction and the second direction.
With the dispensing region 118 spanning the width of the volume
108, the powder 120 may be dispensed along the entire width of the
volume 108 as the hopper 116 moves over the volume 108. As compared
to other patterns of distribution of the powder 120, distributing
the powder 120 along the entire width of the volume 108 may
facilitate achieving a substantially uniform distribution of the
powder 120 as the hopper 116 moves rapidly over the volume 108.
[0036] The hopper 116 may include, in some instances, a shutter 129
movable between an open position (shown in FIGS. 1A and 1B) and a
closed position. In the open position, the shutter 129 may be
spaced away from the dispensing region 118 of the hopper 116 such
that the powder 120 exiting the dispensing region 118 is
substantially unobstructed by the shutter 129. In the closed
position, the shutter 129 may slide over the dispensing region 118
to at least partially obstruct the dispensing region 118 of the
hopper 116 to block the powder 120 from the hopper 116 from
inadvertently falling out of the hopper 116. Thus, controlling the
shutter 129 between the open position and the closed position may
be useful for reducing errant distribution of the powder 120 and,
thus, may facilitate accurately forming the three-dimensional
object 110.
[0037] The shutter 129 may be in the open position as the hopper
116 of a given one of the first material carriage 104a and the
second material carriage 104b moves in a leading position over the
volume 108, thus permitting the powder 120 from the leading
instance of the hopper 116 to be directed toward the volume 108.
The shutter 129 may be in the closed position as the hopper 116 of
a given one of the first material carriage 104a and the second
material carriage 104b moves in a trailing position over the volume
108, thus blocking the powder 120 from the trailing instance of the
hopper 116 to be blocked from falling onto the volume 108. Thus, as
a specific example, the shutter 129 of the hopper 116 associated
with the first material carriage 104a may be in the open position
as the first material carriage 104a precedes the print carriage 106
over the volume 108 while the shutter 129 of the hopper 116
associated with the second material carriage 104b may be in the
closed position as the second material carriage 104b trails the
print carriage 106 over the volume 108. In the reverse direction,
the positions of the respective instances of the shutter 129 may be
reversed.
[0038] In certain implementations, as the shutter 129 is switched
from the closed position to the open position, a small amount of
the powder 120 may fall from the dispensing region 118 of the
hopper 116 in a manner that may be uncontrolled or, further or
instead, in a quantity that is unpredictable. Thus, to reduce the
likelihood of this small amount of the powder 120 may interfere
with accurately forming the three-dimensional object 110, the
shutter 129 may be switched from the closed position to the open
position along at a position in which the dispensing region 118 is
lateral to the volume 108 such that the small amount of the powder
120 may be dumped prior to moving the dispensing region 118 over
the volume 108 to dispense the powder 120 to be formed into a layer
along a top portion of the volume 108.
[0039] In general, the shutter 129 may be moved between the open
position and the closed position according to any one or more of
various different mechanical and/or electrical actuating
mechanisms. Thus, for example, the shutter 129 may slide between
the open position and the closed position through an electrically
controlled actuator (not shown). While the shutter 129 has been
described as sliding between the open position and the closed
position, it should be appreciated that other types of movement of
the shutter 129 may be additionally or alternatively implemented to
control the flow of the powder 120 from the dispensing region 118.
For example, the shutter 129 may be pivotable about a hinge to move
between the open and closed position.
[0040] In certain implementations, the additive manufacturing
system 100 may include a bulk powder source 130, which may be
useful for addressing certain challenges associated with moving the
hopper 116 over the volume 108 as part of a multi-directional
binder jetting process. For example, the bulk powder source 130 may
be sized to contain enough powder sufficient to form one or more
instances of the three-dimensional object 110. The hopper 116 may
be positionable relative to the bulk powder source 130 to receive
the powder 120 from the bulk powder source 130 (e.g., under the
force of gravity). In certain instances, the hopper 116 may be
refilled during the course of fabrication of the three-dimensional
object 110, which may be particularly useful for forming the
storage region 124 of the hopper 116 with a volume suitable for
moving over the volume 108. That is, because the hopper 116 may be
refilled, the storage region 124 may be formed with a relatively
small volume such that the size and weight of the hopper may be
suitable for rapid movement over the volume 108.
[0041] In general, the spreader 114 may be positioned on the
respective instance of the first material carriage 104a and the
second material carriage 104b such that the spreader 114 trails the
dispensing region 118 of the hopper 116 as the dispensing region
118 precedes the at least one ejection orifice 202 of the print
carriage 106 over the volume 108. Thus, as the powder 120 is
dispensed from the dispensing region 118 of the hopper 116 to the
volume 108, the spreader 114 may move over the volume 108 at a
substantially fixed distance to spread the powder 120 into a layer.
In turn, the binder 112 may be distributed from the at least one
ejection orifice 202 onto the layer in a controlled two-dimensional
pattern corresponding to a respective two-dimensional slice of the
three-dimensional object 110.
[0042] In certain instances, a height of the spreader 114 above the
volume 108 may be adjustable. For example, the height of the
spreader 114 above the volume 108 may be adjustable to achieve a
target layer height as the spreader 114 moves over the volume 108
in a direction in advance of the at least one ejection orifice 202
of the print carriage 106. Additionally, or alternatively, the
height of the spreader 114 may be adjustable to move the spreader
114 away from the volume 108 as the spreader 114 moves over the
volume 108 in a direction trailing the at least one ejection
orifice 202 of the print carriage 106. Continuing with this
example, such selective movement of the spreader 114 away from the
volume 108 may be useful, for example, for reducing the likelihood
of unintended contact between the spreader 114--in the trailing
position--and the powder 120 which, in turn, may reduce the
likelihood of introducing errors into the three-dimensional object
110 being formed.
[0043] The spreader 114 may generally include any manner and form
of elongate element useful for spreading the powder 120
substantially uniformly across the volume 108 as the spreader 114
moves over the volume 108. Further, or instead, the spreader 114
may be a unitary body, such as may be useful for reducing the
likelihood of forming debris as the spreader 114 spreads the powder
120 repeatedly over the course of forming multiple instances of the
three-dimensional object 110. Thus, for example, the spreader 114
may be a roller. As used in the context of the spreader 114, a
roller should be understood to include, for example, a
substantially cylindrical shape actively and/or passively rotatable
about the elongate axis of the cylindrical shape. For example, the
roller may be driven to rotate in a direction substantially
opposite a direction of travel of the spreader 114 over the volume
108. As used herein, movement of the roller in the direction
substantially opposite the direction of travel of the spreader 114
should be understood to include rotation of the roller in a
direction opposite to a direction of free rotation of the roller in
the absence of the applied rotational force as the spreader 114
moves over the volume 108 with the roller in contact with the
powder 120. As compared to passive rotation of the roller and/or
active rotation of the roller in the direction of travel of the
spreader 114, rotating the roller in the direction substantially
opposite the direction of travel of the spreader 114 may produce a
more even distribution of the powder 120 in the layer formed by the
spreader 114.
[0044] In general, the print carriage 106 may be selectively
actuatable (e.g., electrically actuatable) to produce a controlled
distribution of the binder 112 in a two-dimensional pattern
associated with the two-dimensional slice of the three-dimensional
object 110 being formed. Given that the two-dimensional pattern may
be different for different two-dimensional slices, the print
carriage 106 may produce varying patterns of the binder 112 as
required for the layer-by-layer fabrication of the
three-dimensional object. These varying patterns may be produced
according to any of various different techniques known in the art
of ink jet printing. Thus, for example, the print carriage 106 may
include at least one print bar. In turn, each print bar may include
a plurality of print heads (e.g., piezoelectric print heads), and
each print head may define at least one of the plurality of
ejection orifices. Each print head may be independently
controllable relative to each of the other print heads to
facilitate accurate delivery of the binder according to a given
controlled two-dimensional pattern associated with a
two-dimensional slice being formed as the print carriage 106 moves
across the volume 108.
[0045] The at least one ejection orifice 202 may be shaped and
arranged according to any of various different patterns useful for
producing a suitable distribution of the binder 112 in a controlled
two-dimensional pattern along the layer. For example, the at least
one ejection orifice 202 may include a plurality of instances of
the at least one ejection orifice 202, and each instance of the at
least one ejection orifice 202 may be substantially similar to each
other instance of the at least one ejection orifice 202. Such
similarity between instances of the at least one ejection orifice
may be useful, for example, for producing uniform distributions of
the binder 112. Further, or instead, the at least one ejection
orifice 202 may include a plurality of orifices spaced relative to
one another to span one or more dimensions along the top of the
volume 108, with such spatial distribution contributing
advantageously to uniformity of binder distribution. As an example,
the at least one ejection orifice 202 may include a plurality of
orifices spaced relative to one another along a direction
substantially perpendicular to an axis defined by back and forth
movement of print carriage 106 over the volume 108 in a first
direction and a second direction opposite one another.
[0046] In certain implementations, the print carriage 106 may be
advantageously formed to have substantially similar performance in
the different directions of movement associated with a
multi-directional binder jetting process. As an example, the at
least one ejection orifice 202 may be directed relative to the
volume 108 to eject the binder 112 in a direction substantially
perpendicular to the volume 108 as the print carriage moves over
the volume 108. This orientation of the at least one ejection
orifice 202 may be useful, for example, for jetting the binder 112
in a manner that is substantially independent of the direction of
movement of the print carriage 106 as the binder 112 is jetted
toward the volume 108. In turn, eliminating or at least reducing
directional artifacts associated with directing the binder 112
toward the volume 108 may result in improvements in accuracy of the
three-dimensional object 110 being formed.
[0047] The print carriage 106 may, in certain instances, define a
plurality of gas assist orifices 204 positioned relative to the at
least one ejection orifice 202 to limit the impact of errant
material on the formation of the three-dimensional object 110. For
example, the gas assist orifices 204 may be disposed on either side
of a plane bisecting the at least one ejection orifice 202. That
is, the gas assist orifices 204 may be positioned to precede and
trail the at least one ejection orifice 202 as the print carriage
106 moves across the volume 108 in a first direction and in a
second direction different from the first direction. A gas (e.g.,
air) may be expelled through the plurality of gas assist orifices
204 as the binder 112 is ejected from the at least one ejection
orifice 202. Expelling gas through the plurality of gas assist
orifices 204 in this way may be useful, for example, for reducing
the presence of fine powder particles, satellite droplets of the
binder 112, or both, above the volume 108. Additionally, or
alternatively, gas may be suctioned through the plurality of gas
assist orifices 204 as the binder 112 is ejected from the at least
one ejection orifice 202. Such suction may, in certain instances,
be useful for reducing the presence of satellite droplets of the
binder 112, fine particles, or both, floating above the volume 108.
In general, reducing satellite droplets of the binder 112, fine
powder particles, or both, above the volume may reduce the
likelihood of such material interfering with the placement of the
binder 112 in a controlled two-dimensional pattern on a layer of
the powder 120 and, thus, may facilitate more accurate formation of
the three-dimensional object 110.
[0048] In certain implementations, the additive manufacturing
system 100 may include a z-stage actuator 132, which may be
mechanically coupled (e.g., directly mechanically coupled) to a
bottom surface 131 of the print box 102. Through actuation of the
z-stage actuator 132, the bottom surface 131 of the print box 102
may be moved in a direction away from the print carriage 106 to
increase a depth dimension of the volume 108 as the
three-dimensional object 110 is formed in the volume 108. In
general, the z-stage actuator 132 may be any of various different
types of known mechanical actuators useful for precisely controlled
vertical translation. For example, the z-stage actuator 132 may be
moveable to move the bottom surface 131 of the print box 102 by a
distance of about the thickness of each layer (e.g., about 40
microns to about 150 microns) with each pass of the print carriage
106 over the volume 108.
[0049] The z-stage actuator 132 may be, for example, releasably
coupled to the print box 102. For example, the z-stage actuator 132
may be decoupled from the print box 102 to facilitate removal of
the print box 102 from the additive manufacturing system 100 once
the three-dimensional object 110 has been formed in the volume. For
example, the print box 102 may be supported on a cart or other
similar structure including a plurality of wheels. Continuing with
this example, upon decoupling the print box 102 from the z-stage
actuator 132, the cart may be rolled to move the print box 102 to
one or more post-processing stations, where excess powder may be
removed from the three-dimensional object 110 and/or the
three-dimensional object 110 may undergo densification into a final
part. It should be appreciated that the use of a cart or other
similar wheeled structure may facilitate, for example, rapidly
replacing the print box 102 as part of a process for rapidly
fabricating multiple instances of the three-dimensional object
110.
[0050] The additive manufacturing system 100 may include at least
one motor 139 coupled to one or more of the first material carriage
104a, the second material carriage 104b, and the print carriage 106
to move each respective component over the volume 108 in the first
direction and the second direction. For example, in instances in
which the first material carriage 104a, the second material
carriage 104b, and the print carriage 106 are bidirectionally
movable over the volume 108 along one or more rails 122, the at
least one motor 139 may include a linear actuator, which may be
particularly useful for precisely controlling position of the
respective components. More generally, however, the at least one
motor 139 may be any of various different types of motors
electrically controllable to move the first material carriage 104a,
the second material carriage 104b, and the print carriage 106 to
carry out any one or more of the various different techniques
described herein.
[0051] The additive manufacturing system 100 may include a
controller 140. The controller may be in electrical communication
with one or more of the at least one motor 139, the first material
carriage 104a, the second material carriage 104b, and the print
carriage 106, the z-stage actuator 132, and the at least one motor
139. The controller 140 may include one or more processors 141
operable to control the at least one motor 139, the first material
carriage 104a, the second material carriage 104b, and the print
carriage 106 to form the three-dimensional object 110.
[0052] The additive manufacturing system 100 may, additionally or
alternatively, include a non-transitory, computer readable storage
medium 142 in communication with the controller 140 and having
stored thereon a three-dimensional model 143 and instructions for
causing the one or more processors 141 to carry out any one or more
of the methods described herein. In certain implementations, the
controller 140 may retrieve the three-dimensional model 143 in
response to user input and generate machine-ready instructions for
execution by the additive manufacturing system 100 to fabricate the
three-dimensional object 110.
[0053] In use, as the first material carriage 104a moves over the
volume 108, a quantity of the powder 120 may be dispensed from the
dispensing region 118 of the first material carriage 104a toward
the volume 108 (e.g., directly onto the volume 108 or toward an
area immediately adjacent to the volume 108). The spreader 114 of
the first material carriage 104a may spread the dispensed quantity
of the powder 120 to form a layer along the top of the volume 108
as the first material carriage 104a moves over the volume 108. The
print carriage 106 may follow the first material carriage 104a in
the first direction, and the binder 112 may be ejected from the at
least one ejection orifice 202 of the print carriage 106 toward the
layer in a controlled two-dimensional pattern corresponding to a
respective two-dimensional slice of the three-dimensional object
110 being formed. Along the controlled two-dimensional pattern, the
binder 112 may generally adhere to the particles of the powder and
to one or more adjacent layers. The second material carriage 104b
may follow the print carriage 106 in the first direction and, in
this trailing position, the spreader 114 of the second material
carriage 104b may be in a raised position, out of contact with the
layer, to reduce the likelihood of distorting the controlled
two-dimensional pattern of the binder 112 in the layer.
[0054] Continuing with this example, the order of movement of the
second material carriage 104b, the print carriage 106, and the
first material carriage 104a may then be reversed to form a second
layer. More specifically, the second material carriage 104b may
move across the volume 108 in a second direction different from the
first direction, and a quantity of the powder 120 may be dispensed
from the dispensing region 118 of the second material carriage 104b
toward the volume 108 (e.g., onto the volume 108 or to an area
immediately adjacent to the volume 108). The spreader 114 of the
second material carriage 104b, in a lowered position, may spread
the powder 120 along the volume 108 to form the second layer of the
powder 120. As the print carriage 106 follows the second material
carriage 104b across the volume 108, the print carriage 106 may
eject the binder 112 toward the layer in a controlled
two-dimensional pattern corresponding to a respective
two-dimensional slice of the three-dimensional object 110 being
formed. Along the controlled two-dimensional pattern, the binder
112 may adhere the particles of the powder 120 to each other and to
at least one other adjacent layer. The first material carriage 104a
may follow the print carriage in the second direction, with the
spreader 114 of the first material carriage 104a in a raised
position above the volume 108 to reduce the likelihood of
interfering with the layer formed by the second material carriage
104b. Thus, movement of the first material carriage 104a, the print
carriage 106, and the second material carriage 104b across the
volume 108 may be alternated in two different directions to form
two-dimensional slices of the three-dimensional object 110 in each
direction of travel. With less wasted motion, as compared to a
single-direction approach requiring repositioning of components
between formation of each slice, the additive manufacturing system
100 may significantly reduce the rate of fabrication of the
three-dimensional object 110.
[0055] In general, increases in fabrication rate associated with
binder jetting processes--whether multi-direction or
single-direction--may be in tension with quality and accuracy goals
associated with the fabrication process. That is, as the rate of
fabrication increases, challenges associated with one or more of
binder placement, powder dispensing, and spreading may become more
pronounced. Accordingly, in the disclosure that follows, certain
techniques are described for maintaining accuracy as fabrication
rates are increased. More specifically, these techniques are
related to thermal energy delivery, powder dispensing, and powder
packing to reduce or eliminate certain sources of inaccuracy that
may become more significant as fabrication rates increase. Unless
otherwise specified or made clear from the context, these
techniques should be understood to be equally applicable to
single-direction binder jetting and multi-directional binder
jetting.
[0056] Thermal Energy Delivery
[0057] In some implementations, the additive manufacturing system
100 may include at least one instance of a thermal energy source
144 movable the volume 108 in coordination with movement of the
spreader 114 over the volume. In general, as the thermal energy
source 144 moves over the volume 108, the thermal energy source 144
may be positioned to direct thermal energy toward the volume 108.
The thermal energy may be directed through the space between the
thermal energy source 144 and a layer on top of the volume 108
according to any manner and form of heat transfer (e.g.,
convection, conduction, radiation, or a combination thereof),
unless otherwise specified or made clear from the context. Thus,
for example, the thermal energy source 144 may be an infrared
energy source, a microwave energy source, or a combination
thereof.
[0058] The first material carriage 104a and the second material
carriage 104b may each include a respective instance of the thermal
energy source 144 such that the thermal energy source 144 is in a
substantially fixed orientation relative to the spreader 114 of the
respective material carriage. In general, the thermal energy source
144 may precede or trail the spreader 114 over the volume 108,
depending on whether application of thermal energy to the volume
108 is intended to occur before or after spreading occurs.
Similarly, the thermal energy source 144 may precede or trail the
at least one ejection orifice 202 of the print carriage 106 over
the volume 108, depending on whether application of thermal energy
to a given layer on top of the volume 108 is intended to occur
before or after the binder 112 has been delivered to the given
layer. For example, in some instances, the thermal energy source
144 may be positioned such that thermal energy is directed to the
layer of the powder 120 on top of the volume 108 after the binder
112 has been applied in a controlled two-dimensional pattern and
before a subsequent layer of the powder 120 is spread across the
volume 108. Timing the application of the thermal energy in this
way may accelerate drying of the binder 112 which, in turn, may
reduce the likelihood of smearing or otherwise distorting the
controlled two-dimensional pattern of the binder 112 in a given
layer on top of the volume 108 as a subsequent layer is formed in a
rapid fabrication process. As a specific example, a first instance
of the thermal energy source 144 may trail the instance of the
spreader 114 of the first material carriage 104a over the volume
108 in a first direction, and a second instance of the thermal
energy source 144 may trail the instance of the spreader 114 of the
second material carriage 104b over the volume 108 in a second
direction opposite the first direction. In this configuration, the
second instance of the thermal energy source 144 may direct thermal
energy toward the volume 108 as the second material carriage 104b
moves in the first direction, trailing the print carriage 106.
Similarly, the first instance of the thermal energy source 144 may
direct thermal energy toward the volume 108 as the first material
carriage 104a moves in the second direction, trailing the print
carriage 106.
[0059] In general, the effectiveness of the thermal energy source
144 in delivering thermal energy to the volume 108 may be a
function of the rate of movement of the thermal energy source 144
over the volume 108. That is, for a given rate of thermal energy
production, slower speeds of movement of the thermal energy source
144 over the volume 108 may result in more effective heat transfer
to the layer on top of the volume 108. Thus, in some instances, the
thermal energy source 144 may be adjustable to produce more thermal
power as the speed of the thermal energy source 144 increases over
the volume 108. Additionally, or alternatively, the thermal energy
source 144 may be moved over the volume 108 at a substantially
constant rate, which may facilitate transferring a predictable and
consistent amount of thermal energy to the layer on top of the
volume 108. Further, or instead, the spreader 114, the print
carriage 106, and the thermal energy source 144 may each be movable
over the volume 108 at substantially the same rate as one another,
which may be useful for coordinating heat transfer with the other
processes associated with formation of the three-dimensional object
110.
[0060] FIG. 3 is a flowchart of an exemplary method 300 of thermal
energy delivery in multi-directional additive manufacturing. In
general, unless otherwise specified or made clear from the context,
the exemplary method 300 may be carried out using any one or more
of the additive manufacturing systems described herein. Thus, for
example, one or more steps of the exemplary method 300 may be
carried out by the additive manufacturing system 100 (FIG. 1A).
[0061] As shown in step 302, the exemplary method 300 may include
spreading a layer of powder across a volume defined by a print box.
The powder may be any one or more of the powders described herein
and, thus, may include metal particles having a composition
suitable for forming a finished part according to predetermined
material specifications. For example, the metal particles may
include one or more components of stainless steel such that,
through densification and/or other post-processing, a finished part
of stainless steel is formed. Still further or instead, spreading
the layer of powder may include spreading according to any one or
more of the spreading techniques described herein. As an example,
spreading the layer of powder may include rolling the powder to
form a substantially uniform layer across the volume.
[0062] As shown in step 304, the exemplary method 300 may include
depositing a binder in a controlled two-dimensional pattern along
the layer. The binder may be any one or more binders known in the
art and suitable for adhering the metal particles of the powder to
one another and to adjacent layers to hold the shape of the
three-dimensional object being formed as a green part in the
volume. The binder may be removable from the three-dimensional
object through subsequent processing, such as processing to densify
the three-dimensional object in instances in which densification of
the three-dimensional object is desirable. Unless otherwise
specified or made clear from the context, depositing the binder in
the controlled two-dimensional pattern along the layer may be
achieved using any one or more of the techniques. Thus, more
specifically, the binder may be deposited along the layer through
ejection from a print carriage moving over the volume (e.g., the
print carriage 106 in FIG. 1A).
[0063] As shown in step 306, the exemplary method may include
directing thermal energy to the layer. Directing thermal energy to
the layer may include increasing at least a local temperature of
the layer and, in some instances, may include substantially
uniformly increasing the temperature of the layer. Further, or
instead, directing thermal energy to the layer may include
directing thermal energy to the layer to dry at least a portion of
the layer. As used in this context, drying should be understood to
include evaporating at least one liquid from at least a portion of
the layer. As an example, the thermal energy may be applied to the
layer (e.g., substantially uniformly) to remove water content that
may be present in the layer. Additionally, or alternatively, the
thermal energy may be directed to portions of the layer on which
the binder is deposited. Directing thermal energy to the binder in
the layer may, for example, accelerate drying the binder, which may
reduce the likelihood of deformation of the pattern of the binder
as a subsequent layer of powder is formed on top of the binder as
part of a layer-by-layer fabrication process. More generally,
directing thermal energy to the binder may be useful for changing
one or more physicochemical properties of the binder. As used in
this context, a change in physicochemical properties of the binder
may include, for example, a change useful for forming the
three-dimensional object as a stronger green part and/or for
improving quality of the final part formed from the
three-dimensional object.
[0064] In certain instances, directing thermal energy to the layer
includes directing thermal energy to the layer from a thermal
energy source moving over the layer. The movement of the thermal
energy source over the layer may be indexed relative to spreading a
subsequent, sequential layer along the volume such that the thermal
energy is directed to the layer before the subsequent, sequential
layer is formed on top of the layer. The thermal energy source may
be any one or more of the thermal energy sources described herein
and, thus, may include any one or more of an infrared energy source
(to direct infrared energy to the layer) or a microwave energy
source (to direct microwave energy to the layer).
[0065] As shown in step 308, the exemplary method 300 may include
depositing an anti-sintering agent along the layer. In certain
instances, the anti-sintering agent may be deposited along the
layer by a print carriage moving over the layer. That is, a print
carriage, such as the print carriage 106, may deliver the
anti-sintering agent and the binder (e.g., through different
ejection orifices) as the print carriage moves over the layer. As
used in this context, an anti-sintering agent should be understood
to include a material that is less sinterable than at least a
portion of the metal particles of the powder. By way of example,
the anti-sintering agent may be used to introduce certain
structural characteristics into a final part formed from the
three-dimensional object. Such structural characteristics may
include an area of weakness useful for separating portions of the
final part from one another.
[0066] As shown in step 310, the exemplary method 300 may include
repeating one or more of the steps of spreading the layer (step
302), depositing the binder (step 304), directing the thermal
energy to the layer (step 306), or depositing the anti-sintering
agent along the layer (step 308) until the three-dimensional object
is complete. More specifically, the exemplary method may include
performing one or more of the steps of spreading the layer (step
302), depositing the binder (step 304), directing thermal energy to
the layer (306), or depositing the anti-sintering agent along the
layer (step 308) in a first direction across the volume and
repeating the respective steps in a second direction, different
from the first direction, across the volume to form alternating
layers of a three-dimensional object. Unless otherwise specified or
made clear from the context, these steps may be repeated in the
first direction and the second direction using the
multi-directional movement of hardware according to any one or more
of the techniques described herein. For example, depositing the
binder may include ejecting the binder from at least one ejection
orifice defined by a print carriage moving in the first direction
and in the second direction, as described herein. Further, or
instead, the second direction may be, for example, substantially
opposite the first direction across the volume such that the steps
are generally performed through back-and-forth movement of
hardware, as described herein.
[0067] Powder Dispensing
[0068] Referring again to FIGS. 1A, 1B, and 2, in some
implementations, the hopper 116 may include a plurality of
dispensing rollers 146 along the dispensing region 118. The
dispensing rollers 146 may be spaced apart from one another to
define a gap. Each dispensing roller 146 may be substantially
cylindrical, which may be useful for defining the gap with a
constant width. In general, the dispensing rollers 146 may rotate
relative to one another to meter and direct the powder 120 through
the gap and toward the volume 108 in advance of movement of the
spreader 114 over the volume 108. Continuing with this example, the
spreader 114 may move over the powder 120 to form a substantially
uniform layer of the powder along the top of the volume 108, and
the binder 112 may be delivered onto this layer from the at least
one ejection orifice 202 of the print carriage 106 as the print
carriage trails the spreader 114 over the volume 108. This process
may be performed in different directions as necessary to carry out
any one or more of the multi-directional binder jetting techniques
described herein. Thus, in general, the dispensing rollers 146 may
be useful for addressing the challenge of accurately dispensing the
powder 120 in front of the spreader 114 as the hopper 116 and the
spreader 114 move across the volume 108 as part of a rapid binder
jetting process and, more specifically, a multi-directional binder
jetting process.
[0069] In certain implementations, the dispensing region 118 may
span a dimension of the volume substantially parallel to the gap
defined by the plurality of dispensing rollers 146 as the hopper
116 moves over the volume 108. Continuing with this example, the
plurality of dispensing rollers 146 may span this dimension of the
volume 108 as the hopper 116 moves over the volume 108 such that
the powder 120 may be substantially evenly distributed along the
dimension. Such a substantially even distribution may, in turn,
facilitate forming a substantially even thickness of the layer
formed as the spreader 114 pushes the distributed powder 120 along
the volume 108. As should be appreciated, improved control of layer
formation may manifest as improved dimensional accuracy of the
three-dimensional object 110 and, ultimately, as improved quality
of a final part formed from the three-dimensional object 110.
[0070] In certain implementations, the plurality of dispensing
rollers 146 may be substantially identical to one another, which
may be useful for facilitating consistent and even distribution of
the powder 120. Thus, for example, each dispensing roller 146 have
a substantially similar diameter. With such similar diameters,
rotating each dispensing roller 146 at the same rate may direct the
powder 120 in a direction substantially perpendicular to a plane
defined by a top of the volume 108. This may be useful, for
example, for reducing the likelihood of producing errant particles
that may interfere with other aspects for formation of the
three-dimensional object. Further, or instead, each dispensing
roller 146 may have the same surface finish, which may be useful
for increasing the likelihood that the dispensing rollers 146 may
wear at substantially the same rate.
[0071] In certain implementations, the hopper 116 may include at
least one rotational motor 148 coupled to one or more of the
dispensing rollers 146 and actuatable to rotate the plurality of
dispensing rollers 146 relative to one another. The at least one
rotational motor 148 may be any of various different known types of
motors arranged for providing rotational motion transmittable to
the dispensing rollers 146. Thus, for example, the at least one
rotational motor 148 may include a rotary actuator.
[0072] In certain instances, the at least one rotational motor 148
may be coupled to the plurality of dispensing rollers 146 such that
the at least one rotational motor 148 is actuatable to rotate the
plurality of dispensing rollers 146 in a counter-rotating direction
relative to one another. In one direction, the counter-rotation may
be useful for imparting a force to the powder 120 in the gap to
expel the powder 120 from the dispensing region 118. Continuing
with this example, each instance of the dispensing roller 146 may
be counter-rotated at substantially the same rotation speed (albeit
in different directions), which may be useful for directing the
powder 120 in a direction substantially perpendicular to a plane
defined by the top of the volume 108. In another direction of
counter-rotation, the counter-rotation may be useful for reducing
inadvertent movement of the powder 120 through the gap.
[0073] The at least one rotational motor 148 may be in electrical
communication with the controller 140 to control speed and
direction of rotation of the at least one rotational motor 148 and,
in turn, to control speed and direction of rotation of the
plurality of dispensing rollers 146. That is, in general, rotation
of the plurality of dispensing rollers 146 may be coordinated with
one or more other aspects of the additive manufacturing system 100.
For example, rotation of the plurality of dispensing rollers 146
may be adjusted in response to one or more changes in parameters
associated with the additive manufacturing system 100, with such
adjustments being useful for maintaining an advantageous
distribution of the powder 120 throughout varying conditions that
may be encountered as the three-dimensional object 110 is formed.
For example, the controller 140 may be configured to actuate the at
least one rotational motor 148 based on movement of the hopper 116
over the volume 108. Continuing with this example, the controller
140 may deactivate the at least one rotational motor 148 when the
hopper 116 is not over the volume 108. Such selective actuation of
the at least one rotational motor 148 may reduce the likelihood of
inadvertently dispensing the powder 120 away from the volume 108
which, in turn, may reduce formation of errant particles of the
powder 120. Additionally, or alternatively, the controller may be
configured to actuate the at least one rotational motor 148 in a
first direction of movement of the hopper 116 over the volume 108
and to pause actuation of the at least one rotational motor 148 in
a second direction of movement of the hopper 116 over the volume,
with the second direction being different from (e.g., opposite) the
first direction.
[0074] In certain implementations, the controller 140 may be
configured to actuate the at least one motor based on speed of
movement of the hopper 116 over the volume 108. Such a variation in
speed may be useful, for example, for driving the plurality of
dispensing rollers 146 to control a rate of ejection of the powder
120 through the gap. Thus, for example, as the hopper 116 moves
over the volume 108 at a higher rate of speed, the controller 140
may adjust actuation of the at least one rotational motor 148 to
increase the angular speed of the plurality of dispensing rollers
146. In turn, this increase in angular speed may produce an
increase in the amount of powder 120 ejected from the dispensing
region 118. Thus, continuing with this example, the amount of
powder 120 dispersed in front of the spreader 114 may be adjusted
to keep pace with increases or decreases in speed of movement of
the spreader 114 over the volume 108.
[0075] In some instances, the position of the shutter 129 with
respect to the dispensing region 118 may be controlled based at
least in part on rotation of the plurality of the dispensing
rollers 146. For example, shutter 129 may be selectively movable
between a first (open) position away from the dispensing region 118
to a second (closed) position below the dispensing region 118 (to
interrupt movement of powder exiting the hopper 116 via the
dispensing region 118), with such movement based at least in part
on rotation of the plurality of dispensing rollers 146. That is, as
the at least one rotational motor 148 is deactivated to cease
rotation of the plurality of dispensing rollers 146, the shutter
129 may move to the closed position to interrupt movement of the
powder 120 through the dispensing region 118.
[0076] FIG. 4 is a flowchart of an exemplary method 400 of
dispensing powder in additive manufacturing. In general, unless
otherwise specified or made clear from the context, the exemplary
method 400 may be carried out using any one or more of the additive
manufacturing systems described herein. Thus, for example, one or
more steps of the exemplary method 400 may be carried out by the
additive manufacturing system 100 (FIG. 1A). Additionally, or
alternatively, unless otherwise indicated or made clear from the
context, the exemplary method 400 may be carried out as part of a
single-direction binder fabrication process, a multi-direction
binder fabrication process, or a combination thereof.
[0077] As shown in step 402, the exemplary method 400 may include
moving a hopper over a volume defined by a print box. In general,
such movement of the hopper over the volume may include any one or
more of the various different techniques for moving a hopper over a
volume as described herein. Thus, unless otherwise specified or
made clear from the context, moving the hopper over the volume may
include any manner and form of moving the hopper 116 (FIG. 1A) over
the volume 108 (FIG. 1A).
[0078] As shown in step 404, the exemplary method 400 may include,
as the hopper moves over the volume, rotating a plurality of
dispensing rollers disposed along a dispensing region defined by
the hopper. The rotation of the plurality of dispensing rollers may
move a powder toward the volume from the dispensing region. In this
way, the powder may be distributed along a top of the volume, where
the powder may be spread to form a layer.
[0079] In general, rotation of the plurality of dispensing rollers
may move the powder toward the volume through a gap defined between
the plurality of dispensing rollers according to any one or more of
various different arrangements described herein. Thus, for example,
the gap and the dispensing region may span a dimension of the
volume substantially perpendicular to a direction of movement of
the hopper over the volume. Additionally, or alternatively,
rotating the plurality of dispensing rollers may include
counter-rotating dispensing rollers of the plurality of dispensing
rollers. In certain instances, rotating the plurality of dispensing
rollers may include controlling a rotation speed of at least one of
the dispensing rollers of the plurality of dispensing rollers based
on a speed of movement of the hopper over the volume. Further, or
instead, rotating the plurality of dispensing rollers may include
controlling a rotation speed of at least one of the dispensing
rollers of the plurality of dispensing rollers based on a position
of the hopper over the volume. As a more specific example,
controlling the rotation speed of the at least one of the
dispensing rollers may include reducing the rotation speed of the
at least one of the dispensing rollers as the hopper moves from a
first side of the volume to a second side of the volume, the second
side opposite the first side. Still further or instead, rotating
the plurality of dispensing rollers may include rotating each
dispensing roller of the plurality of dispensing rollers at
substantially the same rotation speed and, in certain instances, in
a counter-rotating fashion. In some implementations, rotating the
plurality of dispensing rollers may include controlling a rotation
speed of each dispensing roller of the plurality of dispensing
rollers based on a direction of movement of the hopper over the
volume (e.g., activating rotation in one direction of movement and
deactivating rotation in another direction of movement).
[0080] As shown in step 406, the exemplary method 400 may include
spreading the powder along the volume to form a layer of the
powder. As should be appreciated, the uniformity of this layer of
the powder may be function of uniformity of distribution of the
powder ahead of the spreader in step 404. In general, spreading the
powder along the volume may be carried out according to any one or
more of the spreading techniques described herein.
[0081] As shown in step 408, the exemplary method 400 may include,
in a controlled two-dimensional pattern, ejecting a binder from at
least one ejection orifice of a print carriage to the layer of the
powder to form a portion (e.g., a two-dimensional slice) of the
object. The distribution of the binder in this way may be carried
out according to any on or more binder distribution techniques
described herein.
[0082] As shown in step 410, the exemplary method 400 may include
repeating one or more of the steps of moving the hopper (step 402),
rotating the plurality of dispensing rollers to dispense a powder
(step 404), spreading the powder to form a layer along the volume
(step 406), and ejecting a binder to the layer in a controlled
two-dimensional pattern (step 408) to form the object
layer-by-layer.
[0083] Powder Packing
[0084] Referring again to FIGS. 1A, 1B, and 2, in certain
implementations, one or more instances of the spreader 114
associated with the first material carriage 104a and the second
material carriage 104b may be actuatable to vibrate at a frequency
(e.g., a predetermined frequency) to transmit vibration from the
spreader 114 to the powder 120 as the spreader 114 moves across the
volume 108. Such transmission of vibration may be useful, for
example, for packing the powder 120 in the volume 108 as the
spreader 114 spreads the powder 120 to form a layer. In turn, such
an improvement in packing of the powder 120 may improve quality of
the final part formed from the three-dimensional object 110 (e.g.,
reducing layer-to-layer variations of the powder 120 and/or
improving density characteristics of the three-dimensional object
110 being formed). Thus, as fabrication techniques increase in
speed, the transmission of vibration from the spreader 114 to the
powder 120 may facilitate maintaining or, in some cases, improving
quality of the final parts formed from respective instances of the
three-dimensional object 110.
[0085] As indicated above, the spreader 114 may include a roller
and any of the various different vibration techniques described
herein may be applied to implementations of the spreader 114
including the roller. Thus, for the sake of clarity and efficient
explanation, the following discussion of vibration of the spreader
114 shall be understood to be applicable to implementations in
which the spreader includes a roller. However, unless otherwise
specified or made clear from the context, certain aspects of
vibration of the spreader 114 shall be understood to be applicable
to other shapes.
[0086] Returning to the example in which the spreader 114 may be
rotatable in a direction counter to a direction of movement of the
roller across the volume 108 as the roller moves across the volume
108, the spreader 114 may be actuatable to vibrate as the spreader
114 is rotated in a direction counter to the direction of movement
of the spreader 114 such that the vibration of the spreader 114 is
superimposed on the counter rotation of the spreader. In general,
the spreader 114 may be vibrated at a frequency that does not
interfere with the overall counter-rotational movement of the
spreader 114. For example, as the spreader 114 is counter rotated,
a high frequency rotational vibration may be superimposed on the
spreader 114 as the spreader 114 continues to move in a motion that
is, overall, a counter-rotating motion.
[0087] In general, the additive manufacturing system 100 may
include an actuator 150 coupled to the spreader 114. The actuator
150 may impart rotation (e.g., counter rotation) to the actuator
and, further or instead, may impart vibration to the spreader 114
according to any one or more of various different techniques. In
certain applications, the actuator 150 may vibrate the spreader 114
according to any of various different techniques suitable for
imparting to the spreader 114 a vibration having a frequency of
greater than about 1 kHz and less than about 1 MHz. As an example,
the actuator 150 may include an eccentric motor coupled to the
spreader 114 to impart vibration. Additionally, or alternatively,
the actuator 150 may include one or more springs coupled to the
spreader 114. Continuing with this example, vibration may be
imparted to the spreader 114 through force applied to the one or
more springs. Further, or instead, the actuator 150 may include a
voice coil actuator coupled to the spreader 114 such that actuation
of the voice coil actuator may transmit vibration to the spreader
114 at a predetermined frequency. In certain instances, the
spreader 114 may include a piezoelectric coating in electrical
communication with the actuator 150, and the actuator 150 may pulse
the piezoelectric coating to impart vibration to the spreader 114.
Further, or instead, the spreader 114 may include a wall defining a
roller volume, and the actuator 150 may include a pump in fluid
communication with a source of a fluid (e.g., a gas such as air or
a liquid such as water) and the roller volume of the spreader 114.
In use, the pump may be actuated to provide pressurized pulses of
the fluid to the roller volume of the spreader 114. In response to
such pressurized pulses, the wall of the spreader 114 may flex at
the frequency of the pulses.
[0088] FIG. 5 is a flowchart of an exemplary method 500 of packing
powder for additive manufacturing. In general, unless otherwise
specified or made clear from the context, the exemplary method 500
may be carried out using any one or more of the additive
manufacturing systems described herein. Thus, for example, one or
more steps of the exemplary method 500 may be carried out by the
additive manufacturing system 100 (FIG. 1A). Additionally, or
alternatively, unless otherwise indicated or made clear from the
context, the exemplary method 500 may be carried out as part of a
single-direction binder fabrication process, a multi-direction
binder fabrication process, or a combination thereof.
[0089] As shown in step 502, the exemplary method 500 may include
moving at least one roller across a volume defined by a powder box,
with the movement of the at least one roller across the volume
spreading a layer of a powder across the volume. In general, the
layer of the powder may be spreader across the entire volume as the
at least one roller moves across the volume. As an example, the at
least one roller may include the spreader 114 (FIG. 1A) implemented
as a roller as described herein. As a specific example, moving the
at least one roller across the volume may include rotating the at
least one roller in a direction counter to the direction of
movement of the at least one roller, which may be useful for
facilitating spreading the powder. Additionally, or alternatively,
moving the at least one roller across the volume may include moving
the at least one roller at a predetermined frequency across the
volume defined by the powder box.
[0090] As shown in step 504, the exemplary method 500 may include,
as the at least one roller spreads the layer of the volume,
vibrating the at least one roller to pack the powder in the volume.
The vibration may be imparted to the at least one roller in any one
or more of various different directions, as may be useful for
achieving suitable packing characteristics of the powder. Thus,
returning to the example of the counter-rotating roller, vibrating
the at least one roller may include superimposing rotational
vibration of the at least one roller onto the rotation of the at
least one roller, as described herein. Further, or instead,
vibrating the at least one roller may include vibrating the at
least one roller in a direction substantially perpendicular to a
direction of movement of the at least one roller across the
volume.
[0091] In general, vibrating the at least one roller may include
imparting vibration to the roller according to any one or more of
the various different techniques described herein. Thus, for
example, vibrating the at least one roller may include any one or
more of the following techniques: delivering spring force to the at
least one roller via one or more springs coupled to the at least
one roller; controlling an eccentric motor to a predetermined
rotation speed as the eccentric motor is mechanically coupled to
the at least one roller; actuating a voice coil actuator at a
predetermined frequency as the voice coil actuator is mechanically
coupled to the at least one roller; delivering pulsed pneumatic
force to a hollow volume of the at least one roller; electrically
actuating a piezoelectric coating on the at least one roller.
Additionally, or alternatively, vibrating the at least one roller
may include vibrating the at least one roller at a frequency of
greater than about 1 kHz and less than about 1 MHz.
[0092] In certain implementations, the frequency of vibration of
the at least one roller may be based on one or more characteristics
of the powder. Such characteristics may include, for example, size
distribution and/or composition of the powder. For example,
vibrating the at least one roller may include vibrating the at
least one roller at a predetermined frequency corresponding to a
wavelength substantially equal to an average size of particles of
the powder as the at least one roller moves across the powder box
at the predetermined velocity.
[0093] As shown in step 506, the exemplary method 500 may include
delivering a binder from the print carriage to the layer of the
powder in a predetermined two-dimensional pattern associated with
the layer as the print carriage moves over the volume. Delivering
the binder from the print carriage in this way may include any
manner and form of delivery of the binder 112 (FIG. 1A) described
herein.
[0094] As shown in step 508, the exemplary method 500 may include,
for each layer of a plurality of layers, repeating one or more of
the steps of moving the at least one roller across the volume (step
502), vibrating the at least one roller (step 504), and delivering
the binder (step 506) from the print carriage to the respective
layer in a predetermined two-dimensional pattern associated with
the respective layer to form a three-dimensional object. Unless
otherwise specified or made clear from the context, it should be
generally understood that one or more of the steps of the exemplary
method 500 may be carried out as part of a single-direction
fabrication process or a multi-direction fabrication process. Thus,
for example, the steps of moving the at least one roller across the
volume (step 502), vibrating the at least one roller (step 504),
and delivering the binder from the print carriage (step 506) to the
respective layer may be carried out in a first direction across the
volume and in a second direction across the volume, with the second
direction being different from the first direction.
[0095] While certain implementations have been described, other
implementations are additionally or alternatively possible.
[0096] For example, while additive manufacturing systems have been
described as delivering a powder, it should be generally understood
that the powder may have any of various different compositions
useful for forming the three-dimensional object into a dense part
having a desired composition. Thus, for example, the powder in a
given hopper may include any one or more of various different
materials that may be usefully combined to form a dense part. As a
more specific example, the powder may include any one or more of
various different metals alloyable or otherwise combinable with one
another according to a predetermined material specification.
[0097] As another example, while additive manufacturing systems
have been described as delivering the same powder from multiple
hoppers, it should be appreciated that such description has been
for the sake of clarity of explanation. More generally, each hopper
may be associated with a unique powder. That is, in certain
instances, a first powder in a first hopper may have a first size
distribution, and a second powder in a second hopper may have a
second size distribution, different from the first size
distribution. Further, or instead, a first powder in a first hopper
may have a first composition (e.g., different types of particles,
different concentrations of particles, and combinations thereof),
and a second powder in a second hopper may have a second
composition, different from the first composition.
[0098] For example, referring again to FIG. 3, the exemplary method
300 may be carried out using a first powder and a second powder.
This may be useful, for example, for forming a three-dimensional
object with alternating layers having corresponding alternating
compositions. That is, with respect to step 302, in the first
direction, spreading the layer of powder may include dispensing a
first powder from a first hopper and, in the second direction,
spreading the layer of the powder may include dispensing a second
powder from a second hopper. The first powder may include, for
example, metal particles of a first metal, and the second powder
may include, for example, metal particles of a second metal,
different from the first metal.
[0099] The above systems, devices, methods, processes, and the like
may be realized in hardware, software, or any combination of these
suitable for a particular application. The hardware may include a
general-purpose computer and/or dedicated computing device. 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. In another aspect,
the methods may be embodied in systems that perform the steps
thereof, and may be distributed across devices in a number of ways.
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 or other
hardware. In another aspect, means for performing the steps
associated with the processes described above may include any of
the hardware and/or software described above. All such permutations
and combinations are intended to fall within the scope of the
present disclosure.
[0100] 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 thereof. 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 systems and methods described above may
be embodied in any suitable transmission or propagation medium
carrying computer-executable code and/or any inputs or outputs from
same.
[0101] 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.
[0102] It should further be appreciated that the methods above are
provided by way of example. Absent an explicit indication to the
contrary, the disclosed steps may be modified, supplemented,
omitted, and/or re-ordered without departing from the scope of this
disclosure.
[0103] 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.
* * * * *