U.S. patent application number 17/472373 was filed with the patent office on 2021-12-30 for printhead cleaning system.
This patent application is currently assigned to Hewlett-Packard Development Company, L.P.. The applicant listed for this patent is Hewlett-Packard Development Company, L.P.. Invention is credited to Ning Ge, Steven J. Simske, Jun Zeng.
Application Number | 20210402696 17/472373 |
Document ID | / |
Family ID | 1000005836328 |
Filed Date | 2021-12-30 |
United States Patent
Application |
20210402696 |
Kind Code |
A1 |
Ge; Ning ; et al. |
December 30, 2021 |
PRINTHEAD CLEANING SYSTEM
Abstract
According to an example, an apparatus may include a printhead to
deliver a printing liquid from firing chambers through a plurality
of bores arranged along a surface of the printhead. The apparatus
may also include a cleaning system to apply a pressurized cleaning
fluid onto the surface of the printhead while preventing
application of the pressurized cleaning fluid into the firing
chambers through the plurality of bores.
Inventors: |
Ge; Ning; (Palo Alto,
CA) ; Simske; Steven J.; (Ft. Collins, CO) ;
Zeng; Jun; (Palo Alto, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hewlett-Packard Development Company, L.P. |
Spring |
TX |
US |
|
|
Assignee: |
Hewlett-Packard Development
Company, L.P.
Spring
TX
|
Family ID: |
1000005836328 |
Appl. No.: |
17/472373 |
Filed: |
September 10, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16076363 |
Aug 8, 2018 |
11135775 |
|
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PCT/US2017/015862 |
Jan 31, 2017 |
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17472373 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B33Y 30/00 20141201;
B29C 64/35 20170801; B33Y 40/00 20141201; B29C 64/165 20170801;
B41J 2/16552 20130101 |
International
Class: |
B29C 64/35 20060101
B29C064/35; B33Y 30/00 20060101 B33Y030/00; B33Y 40/00 20060101
B33Y040/00; B29C 64/165 20060101 B29C064/165; B41J 2/165 20060101
B41J002/165 |
Claims
1.-15. (canceled)
16. An apparatus comprising: a printhead including a plurality of
bores arranged along a surface of the printhead; and a cleaning
system including: a plurality of pivotable nozzles, a pressuring
device to, during a cleaning phase of the printhead, pressurize a
cleaning fluid to be sprayed out of the plurality of pivotable
nozzles to clean the surface of the printhead, and a pivoting
mechanism to control a movement of the plurality of pivotable
nozzles to cause the plurality of pivotable nozzles to be pointed
toward sections of the surface of the printhead outside of the
plurality of bores of the printhead to allow the pressurized
cleaning fluid to be applied onto the surface of the printhead
while preventing the pressurized cleaning fluid from entering into
the plurality of bores of the printhead.
17. The apparatus according to claim 16, wherein the printhead is
movable between a printing position and a cleaning position,
wherein in the printing position, the printhead delivers a printing
liquid from a plurality of firing chambers through the plurality of
bores onto build material particles, and in the cleaning position,
the cleaning system applies the pressurized cleaning fluid to
remove residual build material particles from the surface of the
printhead.
18. The apparatus according to claim 17, wherein the surface of the
printhead is coated with a stick resistant material to reduce
sticking of the residual build material particles on the surface of
the printhead.
19. The apparatus according to claim 16, wherein the pivoting
mechanism controls the movement of the plurality of pivotable
nozzles to position the plurality of pivotable nozzles at angles
that are not perpendicular to the surface of the printhead.
20. The apparatus according to claim 16, wherein the cleaning
system further includes: a drop generator located under each of the
plurality of pivotable nozzles to force droplets of the pressurized
cleaning fluid to be expelled out of the plurality of pivotable
nozzles.
21. The apparatus according to claim 16, wherein the cleaning
system further includes: a reservoir containing the cleaning fluid,
and a gutter to catch the pressurized cleaning fluid that was
sprayed out of the plurality of pivotable nozzles and return the
pressurized cleaning fluid to the reservoir for reuse.
22. An apparatus comprising: a printhead including a plurality of
bores arranged along a surface of the printhead; and a cleaning
system for cleaning the surface of the printhead when the printhead
is in a cleaning position, the cleaning system including: a
plurality of pivotable nozzles, a pivoting mechanism to control a
movement of the plurality of pivotable nozzles, a reservoir
containing a cleaning fluid, and a pressuring device to pressurize
the cleaning fluid to be sprayed out of the plurality of pivotable
nozzles to clean the surface of the printhead.
23. The apparatus according to claim 22, wherein the pivoting
mechanism controls the movement of the plurality of pivotable
nozzles to cause the plurality of pivotable nozzles to be pointed
toward sections of the surface of the printhead outside of the
plurality of bores of the printhead to allow the pressurized
cleaning fluid to be applied onto the surface of the printhead
while preventing the pressurized cleaning fluid from entering into
the plurality of bores of the printhead.
24. The apparatus according to claim 22, wherein the printhead is
movable between a printing position and the cleaning position,
wherein in the printing position, the printhead delivers a printing
liquid through the plurality of bores onto build material
particles, and in the cleaning position, the cleaning system
applies the pressurized cleaning fluid to remove residual build
material particles from the surface of the printhead.
25. The apparatus according to claim 24, wherein the surface of the
printhead is coated with a stick resistant material to reduce the
residual build material particles being stuck on the surface of the
printhead.
26. The apparatus according to claim 22, wherein the pivoting
mechanism controls the movement of the plurality of pivotable
nozzles to aim the plurality of pivotable nozzles at angles that
are not perpendicular to the surface of the printhead.
27. The apparatus according to claim 22, wherein the cleaning
system further includes: a drop generator located under each of the
plurality of pivotable nozzles to cause droplets of the pressurized
cleaning fluid to be expelled out of the plurality of pivotable
nozzles.
28. The apparatus according to claim 22, wherein the cleaning
system further includes: a gutter to catch the pressurized cleaning
fluid that was sprayed out of the plurality of pivotable nozzles
and return the pressurized cleaning fluid to the reservoir for
reuse.
Description
BACKGROUND
[0001] 3D manufacturing apparatuses that employ additive
manufacturing techniques to build or print parts are gaining in
popularity and use. Some additive manufacturing techniques employ a
layering process in which particles of build material are spread
into a layer and selectively fused together. Selective fusing of
the build material particles may include the application of agents
onto the layer from printheads. Following that process, additional
particles are spread into another layer and selectively fused
together. This process may be repeated for a number of times to
build up a 3D part having a desired configuration.
BRIEF DESCRIPTION OF THE DRAWINGS
[0002] Features of the present disclosure are illustrated by way of
example and not limited in the following figure(s), in which like
numerals indicate like elements, in which:
[0003] FIG. 1A shows a simplified block diagram of an example
apparatus that may include components of a cleaning system;
[0004] FIG. 1B shows simplified diagrams of an example arrangement
of nozzles of the cleaning system and an example arrangement of
bores arranged along the surface of the printhead depicted in FIG.
1A.
[0005] FIGS. 2A-2C, respectively, depict simplified block diagrams
of other example apparatuses that may include components of a
cleaning system;
[0006] FIG. 3 shows a simplified block diagram of an example
three-dimensional (3D) printer that may include a fluid delivery
device and a fluid delivery device cleaning system;
[0007] FIG. 4 depicts a simplified block diagram of another example
apparatus that may be implemented to clean a surface of a fluid
delivery device; and
[0008] FIG. 5 depicts a flow diagram of an example method for
cleaning the surface of a fluid delivery device.
DETAILED DESCRIPTION
[0009] During printing operations using a printhead having a
plurality of bores through which printing liquid is expelled, and
particularly, during printing operations involving build material
particles as may occur during 3D printing, the particles as well as
other debris may become adhered to the surface of the printhead on
which the bores are arranged. Over time, the particles and other
debris may migrate from the surface to the bores, which may clog
the bores or otherwise disrupt firing of printing liquid through
the bores.
[0010] Disclosed herein are apparatuses and methods for cleaning a
printhead surface with pressurized cleaning fluid while preventing
application of the pressurized cleaning fluid into firing chambers
through the bores of the printhead. That is, for instance, the
apparatuses and methods disclosed herein may cause the pressurized
cleaning fluid to be sprayed onto a surface of the printhead on
which the bores of the firing chambers are arranged. The
pressurized cleaning fluid may be sprayed through a plurality of
nozzles. In some examples, the nozzles may be arranged with respect
to the bores to prevent or limit spraying of the cleaning fluid
into the bores. In some examples, the nozzles may be angled with
respect to the plane of the surface to direct the cleaning fluid
sprays away from the bores. In some examples, the nozzles may be
rotatable to vary the angles at which the cleaning fluid sprays
land on the surface. In some examples, a charging electrode and a
deflector plate may be used to electrically charge and steer
droplets of the pressurized cleaning fluid to intended locations on
the surface.
[0011] Through implementation of the apparatuses and methods
disclosed herein, the surface on which firing chamber bores are
arranged may be cleaned with pressurized cleaning fluid while
preventing the pressurized cleaning fluid from being applied into
the bores. Thus, for instance, build material particles and other
debris may be removed from the surface of the printhead prior to
the build material particles and other debris migrating into the
bores.
[0012] Before continuing, it is noted that as used herein, the
terms "includes" and "including" mean, but are not limited to,
"includes" or "including" and "includes at least" or "including at
least." The term "based on" means, but is not limited to, "based
on" and "based at least in part on."
[0013] With reference first to FIG. 1A, there is shown a simplified
block diagram of an example apparatus 100 that may include
components of a cleaning system. It should be understood that the
apparatus 100 depicted in FIG. 1A may include additional components
and that some of the components described herein may be removed
and/or modified without departing from a scope of the apparatus 100
disclosed herein.
[0014] The apparatus 100 may include a printhead 102 (which is also
recited herein as a delivery device or a fluid delivery device)
that is to deliver a printing liquid 104 onto a media (not shown)
from firing chambers 106 through a plurality of bores 108 (which
are also recited herein as channels) arranged along a surface 110
of the printhead 102. The surface 110 of the printhead 102 may be
part of a bore plate 112 on the printhead 102. The firing chambers
106 may include firing devices (shown as element 114 in FIGS.
2A-2C) such as thermal inkjet resistors, piezoelectric actuators,
or the like. For instance, the firing devices may be activated or
actuated to cause droplets of the printing liquid 104 to be
expelled through the bores 108 and onto media. The media may be
paper, build material particles, or any suitable material upon
which the printing liquid 104 may be delivered. The printing liquid
104 may be an ink, a dye, a fusing agent, a detailing agent, or the
like. By way of particular example, the printing liquid 104 is an
agent that is to one of enhance melting of build material particles
(e.g., fusing agent) and limit melting of build material particles
(e.g., detailing agent) in the fabrication of 3D objects from the
build material particles.
[0015] The bores 108 may be arranged along a surface 110 of the
printhead 102 that faces the media upon which the printing liquid
104 is delivered. Additionally, the bores 108 may be arranged in
parallel rows that extend into the illustration shown in FIG. 1A.
By way of example, a large number of firing chambers 106 and bores
108 may be arranged along parallel rows, for instance, numbering in
the tens to the thousands such that the printing liquid 104 may be
delivered onto relatively large swaths of media, e.g., about 6 to
about 30 inches across.
[0016] The apparatus 100 may also include a cleaning system 120
that is to apply a pressurized cleaning fluid 122 onto the surface
110 of the printhead 102 on which the bores 108 are arranged.
Particularly, the cleaning system 120 may apply the pressurized
cleaning fluid 122 onto the surface 110 while preventing
application of the pressurized cleaning fluid 122 into the firing
chambers 106 through the bores 108. That is, for instance, the
cleaning system 120 may apply the pressurized cleaning fluid 122
onto the surface 110 without directing the pressurized cleaning
fluid 122 into the bores 108. Generally speaking, the cleaning
fluid 122 may be water, solvent, or other suitable fluid for
cleaning the surface 110 of the printhead 102 without, for
instance, damaging or degrading the bore plate 112. In addition, or
in other examples, the cleaning fluid 122 may include a substance
that may provide a benefit to the bore plate 112, e.g., the
cleaning fluid 112 may replace a substance that may have be
provided on the bore plate 112 and may have been removed during
use.
[0017] The cleaning system 120 (which is also recited herein as a
delivery device cleaning apparatus) may include a plurality of
nozzles 124 through which the pressurized cleaning fluid 122 may be
applied to the surface 110 of the printhead 102 or equivalently,
the surface 110 of the bore plate 112. As shown, the pressurized
cleaning fluid 112 may be supplied to the nozzles 124 through a
conduit 126. That is, the pressurized cleaning fluid 122 may be
supplied into the conduit 126 from a pressurizing device (shown in
FIGS. 2A-2C) as denoted by the arrow 128 and may be expelled or
sprayed through the nozzles 124. The pressurized cleaning fluid 122
may be sprayed from the nozzles 124 as aerosol sprays, nanosprays,
ultrasonic sprays, etc. The pressurizing device may include a
compressor, a heater, a pump, or other mechanism for pressurizing
the cleaning fluid 122 and delivering the pressurized cleaning
fluid to the nozzles 124 to be sprayed onto the surface 110.
[0018] According to examples, the nozzles 124 may be positioned
such that the pressurized cleaning fluid 122 is applied onto the
surface 110 while preventing application of the pressurized
cleaning fluid into the firing chambers 106 through the bores 108.
As shown in FIG. 1A, the nozzles 124 may be positioned with respect
to the printhead 102 to direct the pressurized cleaning fluid 122
onto areas of the surface 110 at which the bores 108 are not
positioned. This is further shown in FIG. 1B, which depicts
simplified diagrams 150 of an example arrangement of nozzles 124 of
the cleaning system 120 and an example arrangement of the bores 108
arranged along the surface 110 of the printhead 102. In other
words, FIG. 1B depicts a top view of the nozzles 124 and a bottom
view of the surface 110 of the printhead 102 being supplied with
the pressurized cleaning fluid as shown in FIG. 1A.
[0019] As shown in FIG. 1B, the bores 124 may be positioned on a
substrate 152 that may house the conduits 126 that are in fluid
communication with a pressurizing device and may maintain the
nozzles 124 in a predetermined arrangement. Particularly, for
instance, the nozzles 124 may be arranged to substantially surround
the bores 108 such that the nozzles 124 deliver pressurized
cleaning fluid 122 onto areas of the surface 110 as identified by
the shaded region 154. That is, the nozzles 124 may be arranged to
deliver the pressurized cleaning fluid 122 onto the surface 110
without delivering the pressurized cleaning fluid 122 into the
bores 108.
[0020] Turning now to FIGS. 2A-2C, there are respectively shown
simplified block diagrams of other example apparatuses 200, 230,
250 that may include components of a cleaning system. It should be
understood that the apparatuses 200, 230, 250 respectively depicted
in FIGS. 2A-2C may include additional components and that some of
the components described herein may be removed and/or modified
without departing from scopes of the apparatuses 200, 230, 250
disclosed herein.
[0021] The apparatuses 200, 230, 250 depicted in FIGS. 2A-2C may
include many of the same elements as those discussed above with
respect to FIGS. 1A and 1B and thus, the common elements are not
described again in detail with respect to FIGS. 2A-2C. Instead, it
should be understood that the descriptions of the common elements
provided above with respect to FIGS. 1A and 1B are intended to also
describe those elements with respect to FIGS. 2A-2C.
[0022] With reference first to FIG. 2A, the printhead 102 in the
apparatus 200 may include a stick resistant material 202 applied to
a bottom surface of the bore plate 112. Generally speaking, the
stick resistant material 202 may be any suitable material that
reduces or prevents sticking of particles and/or enhances removal
of particles that may have become stuck to the material 202. By way
of example, the stick resistant material 202 may be
polytetrafluoroethylene (PTFE) and may be applied as a layer to the
bottom surface of the bore pate 112 through any suitable deposition
process. In addition, the stick resistant material 202 may be
applied such that the bores 108 remain uncovered as shown in FIG.
2A. As such, the nozzles 124 of the cleaning system 120 may apply
pressurized cleaning fluid to exposed surfaces of the layer of
stick resistant material 202. It should be understood that the
stick resistant material 202 may be applied to the printheads 102
in any of the example apparatuses 100, 200, 230, 250 disclosed
herein.
[0023] As also shown in FIG. 2A, the nozzles 124 may be positioned
at angles that are not perpendicular to the plane at which the bore
plate 112 extends. That is, for instance, the nozzles 124 may be
angled to direct the pressurized cleaning fluid in directions away
from respective sets of the bores 108. For instance, the nozzles
124 may be angled such that they face directions away from their
nearest bores 108 as shown in FIG. 2A.
[0024] The cleaning system 120 may also include a pressurizing
device 204 that is to feed the pressurized cleaning fluid 122 to
the nozzles 124 through the conduits 126. The pressurizing device
204 may be a compressor, a heater, a pump, or other mechanism for
pressurizing a cleaning fluid 206, which may be contained in a
reservoir 208 that the pressurizing device 204 may access. The
reservoir 208 may be refilled as necessary from a cleaning fluid
source (not shown) and/or from recycling of the cleaning fluid 122
used to clean the surface 110 of the printhead 102.
[0025] With reference now to FIG. 2B, the cleaning system 120 of
the apparatus 230 is depicted as including all of the same elements
as the cleaning system 120 of the apparatus 200. However, in
contrast to the cleaning system 120 in the apparatus 200, the
nozzles 124 in the cleaning system 120 of the apparatus 230 may be
movable. That is, for instance, the nozzles 124 may be pivotable as
indicated by the arrows 232 such that the nozzles 124 may direct
pressurized cleaning fluid 122 to different sections of the surface
110 outside of the bores 108. Additionally, the nozzles 124 may be
pivoted to vary the angles at which the pressurized cleaning fluid
122 is applied to the surface 110. For instance, the nozzles 124
may be pivoted to angles that may force particles on the surface
110 away from the bores 108.
[0026] The nozzles 124 may be rotated through any suitable pivoting
mechanism while enabling fluid communication with the conduits 126.
In addition, the pivoting mechanism may include actuators that a
controller (not shown) may control. By way of example, the
controller may control the pressurizing device and the pivoting
mechanisms to apply the pressurized cleaning fluid 122 onto
different sections of the surface 110 according to a preset routine
that is to clean the surface 110 without applying the pressurized
cleaning fluid 122 into the bores 108.
[0027] Turning now to FIG. 2C, the cleaning system 120 of the
apparatus 250 is depicted as including all of the same elements as
the cleaning system 120 of the apparatus 200. However, the cleaning
system 120 in the apparatus 250 may have additional components as
compared with the cleaning system 120 in the apparatus 200.
Generally speaking, the cleaning system 120 in the apparatus 250
may include components to continuously supply pressurized cleaning
fluid 122 through the nozzle 124. As shown, the cleaning system 120
may include a drop generator 252 that may generate and expel
droplets 254 of the pressurized cleaning fluid 122. That is, the
drop generator 252 may force droplets 254 of the cleaning fluid 122
to be generated and expelled with sufficient force to enable the
droplets 254 to contact the surface 110. While the droplets 254 are
in flight, the trajectories of the droplets 254 may be controlled
to thus control the locations on the surface at which the droplets
254 make contact.
[0028] Particularly, the cleaning system 120 may include a charge
electrode 256 that is to receive an electrical charge from a power
source 258. The cleaning system 120 may also include a deflector
plate 260 that may be controlled by and may receive power from a
controller 262. As the droplets 254 are expelled through the nozzle
124, the droplets 254 pass through the charge electrode 256, and
the droplets 254 may receive an electrical charge from the
electrical field generated by the charge electrode 256. In
addition, when activated, the deflector plate 260 may generate an
electrostatic charge that may apply a force on the charged droplets
254 to alter the trajectories of the charged droplets 254 during
flight. That is, the controller 262 may vary the voltage applied to
the deflector plate 260 to vary the electrostatic charge generated
and controllably vary the trajectories of the droplets 254 such
that the droplets 254 land on intended locations of the surface
110.
[0029] In this regard, the controller 262 may control the amount of
deflection applied onto the charged droplets 254 to control
application of the cleaning fluid droplets 254 onto the surface
110. Particularly, for instance, the controller 262 may control the
deflector plate 260 to apply the cleaning fluid droplets 254 onto
the surface while preventing application of the cleaning fluid
droplets 254 into the firing chambers 106 through the bores 108.
The locations on the surface 110 at which the droplets 254 are
applied may further be controlled through movement of the printhead
102 and/or the cleaning system 120 with respect to each other as
indicated by the arrow 264.
[0030] According to examples, the droplet generator 252 may
generate and fire the droplets 254 in a continuous manner. That is,
for instance, the droplet generator 252 may continue to generate
and fire the droplets 254 even though the droplets 254 may not be
able to reach the intended locations on the surface 110. In these
examples, and as shown in FIG. 2C, the cleaning system 120 may also
include a gutter 266 to which excess, e.g., droplets 254 that are
not intended to be directed to the surface 110, may be directed.
For instance, the droplets 254 may be directed to the gutter 266
when an electrostatic force is not applied onto the droplets 254 by
the deflector plate 260. The droplets 254 collected by the gutter
266 may be discarded or returned to the reservoir 208 for reuse as
indicated by the arrow 268.
[0031] Although not shown in FIGS. 2A-2C, the apparatuses 200, 230,
250 may also include a cleaning fluid recovery system (not shown)
that may collect used cleaning fluid and may discard the used
cleaning fluid. The cleaning fluid recovery system may additionally
or in other examples collect the used cleaning fluid, filter
particles from the collected cleaning fluid, and may reintroduce
the filtered cleaning fluid for reuse in cleaning the surfaces 110
of a printhead 102. In addition or in other examples, the
apparatuses 200, 230, 250 may include a wiping mechanism (not
shown) that may be implemented to wipe the cleaning fluid as well
as debris from the surface 110.
[0032] With reference now to FIG. 3, there is shown a simplified
block diagram of an example three-dimensional (3D) printer 300 that
may include a fluid delivery device and a fluid delivery device
cleaning system. It should be understood that the 3D printer 300
depicted in FIG. 3 may include additional components and that some
of the components described herein may be removed and/or modified
without departing from a scope of the 3D printer 300 disclosed
herein.
[0033] The 3D printer 300 may include a build area platform 302, a
build material supply 304 containing build material particles 306,
and a recoater 308. The build material supply 304 may be a
container or surface that is to position build material particles
306 between the recoater 308 and the build area platform 302.
Generally speaking, 3D objects or parts are to be generated from
the build material particles 306 and the build material particles
306 may be formed of any suitable material including, but not
limited to, polymers, metals, and ceramics. In addition, the build
materials 106 may be in the form of a powder.
[0034] The recoater 308 may move in a direction as denoted by the
arrow 310, e.g., along the y-axis, over the build material supply
304 and across the build area platform 302 to spread a layer 312 of
the build material particles 306 over a surface of the build area
platform 302. The recoater 108 may also be returned to a position
adjacent the build material supply 304 following the spreading of
the build material particles 106. The recoater 108 may be a doctor
blade, roller, a counter rotating roller or any other device
suitable for spreading the build materials 106 over the build area
platform 302. The 3D printer 300 may also include a plurality of
warming devices 311 arranged in an array above the build area
platform 302. In addition, or in other examples, the print bed 302
may be heated to apply heat onto spread layers of the build
material particles 306.
[0035] The 3D printer 300 may further include a fluid delivery
device 314 and a radiation generator 316, which may both be scanned
across the build area platform 302 in both of the directions
indicated by the arrow 318, e.g., along the x-axis. The delivery
device 314 may be, for instance, a thermal inkjet printhead, a
piezoelectric printhead, or the like, and may extend a width of the
build area platform 302. The fluid delivery device 314 may be
equivalent to the printheads 102 discussed above. In other examples
in which the fluid delivery device 314 does not extend the width of
the build area platform 302, the fluid delivery device 314 may also
be scanned along the y-axis to thus enable the fluid delivery
device 314 to be positioned over a majority of the area above the
build area platform 302. The fluid delivery device 314 may be
attached to a moving XY stage or a translational carriage (neither
of which is shown) that is to move the delivery device 314 adjacent
to the build area platform 302 in order to deposit respective
liquids in predetermined areas of a layer of the build material
particles 306.
[0036] The fluid delivery device 314 may include a plurality of
bores 108 (FIGS. 2A-2C) arranged on a surface 110 of the fluid
delivery device 314 through which printing liquid may be ejected
onto the build material particles 306 in the build material layer
312. According to some examples, the printing liquid may be a
fusing agent and/or a detailing agent. A fusing agent may be a
liquid that is to absorb fusing radiation (e.g., in the form of
light and/or heat) to cause the build material particles 306 upon
which the fusing agent has been deposited to fuse together when the
fusing radiation is applied. A detailing agent may be a liquid that
may absorb significantly less of the fusing radiation as compared
with the fusing agent. In one example, the detailing agent may
prevent or significantly reduce the fusing together of the build
material particles 306 upon which the detailing agent has been
deposited. In other examples, the detailing agent may be
implemented to provide coloring to exterior portions of the build
material particles 306 that have been fused together.
[0037] Following deposition of the printing liquid onto selected
areas of the layer 312 of the build material particles 306, the
radiation generator 316 may be implemented to apply fusing
radiation onto the build material particles 306 in the layer 312.
Particularly, for instance, the radiation generator 316 may be
activated and moved across the layer 312, for instance, along the
directions indicated by the arrow 318, to apply fusing radiation in
the form of light and/or heat onto the build material particles
306. Examples of the radiation generator 318 may include a UV, IR
or near-IR curing lamp, an IR or near-IR light emitting diode
(LED), a halogen lamp emitting in the visible and near-IR range, or
a laser with desirable electromagnetic wavelengths. According to an
example, the fluid delivery device 314 and the fusing radiation
generator 316 may be supported on a carriage (not shown) that may
be scanned over the build area platform 302 in the directions
denoted by the arrow 318.
[0038] Following application of the radiation to fuse selected
sections of the build material particles 306 together, the build
area platform 302 may be lowered as denoted by the arrow 320, e.g.,
along the z-axis. In addition, the recoater 308 may be moved across
the build area platform 302 to form a new layer 312 of build
material particles 306 on top of the previously formed layer.
Moreover, the fluid delivery device 314 may deposit printing liquid
onto selected locations of the new layer 312. The above-described
process may be repeated until a predetermined number of layers have
been formed to fabricate a green body of a desired 3D part.
[0039] During the process discussed above, some of the build
material particles 306 may become attached to a surface 110 of the
fluid delivery device 314 on which the bores 108 are arranged. This
may occur because the build material particles 306 may have small
particle sizes, e.g., between about 20 microns to about 80 microns,
and may thus be disturbed and may become airborne relatively
easily. For instance, some of the build material particles 306 may
splash toward the surface 110 during application of the printing
liquid through the bores 108. According to examples, the 3D printer
300 may include a cleaning system 322 to clean the surface 110 of
the fluid delivery device 314. The cleaning system 322 may be
similar to any of the cleaning systems 120 discussed above with
respect to FIGS. 1A-2C. In addition, the cleaning system 322 may be
part of service station of the 3D printer 300.
[0040] According to examples, the fluid delivery device 314
(printhead 102) may be moved between a printing position and a
cleaning position. In the printing position, the fluid delivery
device 314 may move over the print bed 302 to apply printing liquid
onto the build material particles 306 in a layer 312. In the
cleaning position, the fluid delivery device 314 may move over the
cleaning system 322 such that pressurized cleaning fluid 122 may be
applied to the surface 110 of the fluid delivery device 314.
Additionally, while in the cleaning position, additional service
station operations may be performed on the fluid delivery device
314, such as, wiping, capping, testing, etc.
[0041] As further shown in FIG. 3, the 3D printer 300 may include a
controller 330 that may control operations of the build area
platform 302, the build material supply 304, the recoater 308, the
warming devices 311, the fluid delivery device 314, the radiation
generators 316, and the cleaning system 322. Particularly, for
instance, the controller 330 may control actuators (not shown) to
control various operations of the 3D printer 300 components. The
controller 330 may be a computing device, a semiconductor-based
microprocessor, a central processing unit (CPU), an application
specific integrated circuit (ASIC), a graphics processing unit
(GPU), a field programmable gate array (FPGA), and/or other
hardware device. Although not shown, the controller 330 may be
connected to the 3D printer 300 components via communication
lines.
[0042] The controller 330 may be in communication with a data store
332. The data store 332 may include data pertaining to a 3D part to
be printed by the 3D printer 300. For instance, the data may
include the locations in each build material layer 312 that the
fluid delivery device 314 is to deposit printing liquid to form the
green body of the 3D part. In one example, the controller 330 may
use the data to control the locations on each of the build material
layers 312 that the fluid delivery device 314 deposits the printing
liquid.
[0043] Additionally, the controller 330 may control when the fluid
delivery device 314 is moved to the cleaning position over the
cleaning system 322. For instance, the controller 330 may determine
when a certain amount of time has expired, when the fluid delivery
device 314 has deposited a certain amount of printing liquid, when
a user has instructed the controller 330 to perform a cleaning
operation, or the like. In response to the determination, the
controller 330 may control an actuator of the fluid delivery device
314 or an actuator of a carriage on which the delivery device 314
is supported to move the fluid delivery device 314 to a position to
be cleaned by the cleaning system 322.
[0044] Turning now to FIG. 4, there is shown a simplified block
diagram of another example apparatus 400 that may be implemented to
clean a surface 110 of a fluid delivery device. It should be
understood that the apparatus 400 depicted in FIG. 4 may include
additional components and that some of the components described
herein may be removed and/or modified without departing from a
scope of the apparatus 400 disclosed herein.
[0045] The apparatus 400 may include a controller 402 that may
control operations of the apparatus 400 and a data store 404 that
may store data that is accessible by the controller 402. The
controller 402 may be a semiconductor-based microprocessor, a
central processing unit (CPU), an application specific integrated
circuit (ASIC), a field-programmable gate array (FPGA), a graphics
processing unit (GPU), and/or other hardware device. The apparatus
400 may also include a memory 410 that may have stored thereon
machine readable instructions 412-414 (which may also be termed
computer readable instructions) that the controller 402 may
execute. The memory 410 may be an electronic, magnetic, optical, or
other physical storage device that contains or stores executable
instructions. The memory 410 may be, for example, Random Access
Memory (RAM), an Electrically Erasable Programmable Read-Only
Memory (EEPROM), a storage device, an optical disc, and the like.
The memory 410, which may also be referred to as a computer
readable storage medium, may be a non-transitory machine-readable
storage medium, where the term "non-transitory" does not encompass
transitory propagating signals.
[0046] The apparatus 400 may be a computing device such as a
personal computer, a laptop computer, a smartphone, a server
computer, a tablet computer, or the like. In other examples, the
apparatus 400 may be or form part of a 3D printer. The controller
402 may communicate instructions to a fluid delivery device 420 and
cleaning system components 430 over a network, through a wired
connection, a bus, or the like.
[0047] With reference to FIGS. 1A, 3, and 4, the controller 402 may
fetch, decode, and execute the instructions 412 to position the
fluid delivery device 420 (printhead 102) over a cleaning system
120, 322. That is, the controller 402 may execute the instructions
412 to cause the fluid delivery device 420 to be moved to a
cleaning position over the cleaning system 322. As discussed above,
the fluid delivery device 420 may have firing chambers 106 and a
plurality of channels 108 provided along a plate 112 through which
printing liquid is to be expelled from the firing chamber's
106.
[0048] The controller 402 may also fetch, decode, and execute the
instructions 414 to control the cleaning system components 430 to
apply pressurized cleaning fluid 122 to the plate 112 (e.g.,
surface 110) while avoiding application of the pressurized cleaning
fluid into the firing chambers 106 through the plurality of
channels 108. The cleaning system components 430 may include a
pressurizing device 204 and/or the nozzles 124. For instance, the
controller 402 may control the pressurizing device 204 to vary the
amount of pressure applied to cleaning fluid contained in the
conduits 126 to vary the timing/volume of pressurized cleaning
fluid 122 sprayed onto the plate 112. In addition or as another
example, the controller 402 may control the nozzles 124 either
individually or collectively to vary the sizes of the openings in
the nozzles 124 and thus vary the timing/volume of pressurized
cleaning fluid 122 sprayed onto the plate 112. Moreover, the
controller 402 may control other aspects of the pressurized
cleaning fluid 122 delivery as discussed above with respect to
FIGS. 2A-2C.
[0049] Various manners in which the apparatus 400 may be
implemented are discussed in greater detail with respect to the
method 500 depicted in FIG. 5. Particularly, FIG. 5 depicts a flow
diagram of an example method 500 for cleaning a surface 110 of a
fluid delivery device 102, 314. It should be understood that the
method 500 depicted in FIG. 4 may include additional operations and
that some of the operations described therein may be removed and/or
modified without departing from the scope of the method 500. The
description of the method 500 is made with reference to the
features depicted in FIGS. 1A-4 for purposes of illustration.
Generally speaking, the controller 402 of the apparatus 400 may
implement or execute some or all of the instructions 412-414 stored
on the memory 410 to perform the method 500. However, it is
contemplated that other computing devices may implement or perform
the operations described with respect to the method 500.
[0050] At block 502, a fluid delivery device 314 (e.g., a printhead
102) may be positioned over a cleaning system 120, 322. The
cleaning system 120, 322 may include components that are to apply a
pressurized cleaning fluid onto the fluid delivery device 102, 314.
In addition, the fluid delivery device 314 may have firing chambers
106 and a plurality of channels 108, in which the channels 108 may
be provided along a plate 122 through which printing liquid is to
be expelled from the firing chambers 106.
[0051] At block 504, the components of the cleaning system 120, 322
may be implemented to apply pressurized cleaning fluid 122 to the
plate 112 (e.g., surface 110) while avoiding application of the
pressurized cleaning fluid 122 into the firing chambers 106 through
the plurality of channels 108. The components of the cleaning
system 120, 322 may be implemented in any of the manners described
above with respect to FIGS. 1A-4 to apply the pressurized cleaning
fluid while avoiding application of the pressurized cleaning fluid
122 into the firing chambers 106.
[0052] According to examples, additional cleaning operations may be
performed on the fluid delivery device 102, 314. For instance, the
cleaning system 120, 322 may include a wiping mechanism that will
be implemented to wipe the surface 110 to remove the cleaning fluid
and debris from the surface 110. In addition or in other examples,
the cleaning system 120, 322 may include a shaking mechanism that
may shake the print head 102, 314 prior to application of the
cleaning fluid 122. As other examples, the cleaning system 120, 322
may include an ultrasound mechanism that may apply ultrasound onto
the printhead. In these examples, loose debris may be removed from
the surface 110 prior to application of the cleaning fluid 122,
which may reduce the chances of debris being delivered into the
firing chambers 106 through the bores 108.
[0053] Some or all of the operations set forth in the method 500
may be contained as utilities, programs, or subprograms, in any
desired computer accessible medium. In addition, the method 500 may
be embodied by computer programs, which may exist in a variety of
forms both active and inactive. For example, they may exist as
machine readable instructions, including source code, object code,
executable code or other formats. Any of the above may be embodied
on a non-transitory computer readable storage medium.
[0054] Examples of non-transitory computer readable storage media
include computer system RAM, ROM, EPROM, EEPROM, and magnetic or
optical disks or tapes. It is therefore to be understood that any
electronic device capable of executing the above-described
functions may perform those functions enumerated above.
[0055] Although described specifically throughout the entirety of
the instant disclosure, representative examples of the present
disclosure have utility over a wide range of applications, and the
above discussion is not intended and should not be construed to be
limiting, but is offered as an illustrative discussion of aspects
of the disclosure.
[0056] What has been described and illustrated herein is an example
of the disclosure along with some of its variations. The terms,
descriptions and figures used herein are set forth by way of
illustration only and are not meant as limitations. Many variations
are possible within the spirit and scope of the disclosure, which
is intended to be defined by the following claims--and their
equivalents--in which all terms are meant in their broadest
reasonable sense unless otherwise indicated.
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