U.S. patent application number 16/605375 was filed with the patent office on 2020-11-12 for parts and outer layers having differing physical properties.
The applicant listed for this patent is HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P.. Invention is credited to William E. Hertling, Jeff Porter.
Application Number | 20200353689 16/605375 |
Document ID | / |
Family ID | 1000005002406 |
Filed Date | 2020-11-12 |
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United States Patent
Application |
20200353689 |
Kind Code |
A1 |
Hertling; William E. ; et
al. |
November 12, 2020 |
PARTS AND OUTER LAYERS HAVING DIFFERING PHYSICAL PROPERTIES
Abstract
Some examples include a computer-readable medium storing
executable instructions which, when executed by a processor, are to
cause the processor to receive electronic data describing a part to
be manufactured in a three-dimensional additive manufacturing
process; develop instructions using the electronic data for
creating an outer layer on a surface of the part in the additive
manufacturing process, where the outer layer having a physical
property that differs from that of the surface of the part; and
manufacture the part using the instructions.
Inventors: |
Hertling; William E.;
(Vancouver, WA) ; Porter; Jeff; (Vancouver,
WA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P. |
Spring |
TX |
US |
|
|
Family ID: |
1000005002406 |
Appl. No.: |
16/605375 |
Filed: |
January 31, 2018 |
PCT Filed: |
January 31, 2018 |
PCT NO: |
PCT/US2018/016273 |
371 Date: |
October 15, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B29C 64/393 20170801;
G06T 17/10 20130101; B33Y 50/02 20141201 |
International
Class: |
B29C 64/393 20060101
B29C064/393; G06T 17/10 20060101 G06T017/10 |
Claims
1. A computer-readable medium storing executable instructions
which, when executed by a processor, are to cause the processor to:
receive electronic data describing a part to be manufactured in a
three-dimensional additive manufacturing process; develop
instructions using the electronic data for creating an outer layer
on a surface of the part in the additive manufacturing process, the
outer layer having a physical property that differs from that of
the surface of the part; and manufacture the part using the
instructions.
2. The computer-readable medium of claim 1, wherein the physical
property is magnetism, an ultraviolet color, or an infrared
color.
3. The computer-readable medium of claim 1, wherein the physical
property is a fluorescent color that contrasts with the surface of
the part under ultraviolet light.
4. The computer-readable medium of claim 1, wherein the outer layer
has varying thicknesses.
5. The computer-readable medium of claim 4, wherein the varying
thickness is determined based on the electronic data such that the
thickness is greater in positions on the surface of the part where
artifacts or imperfections are likely to occur.
6. A computer-readable medium storing executable instructions
which, when executed by a processor, are to cause the processor to:
generate a model of a three-dimensional part, the model including
an outer layer abutting a surface of the three-dimensional part,
the outer layer and the surface sharing a common visually
perceptible color and not sharing a physical property; and
manufacture the three-dimensional part in accordance with the model
and using additive manufacturing.
7. The computer-readable medium of claim 6, wherein the physical
property is magnetism, a fluorescent color that contrasts with the
surface of the three-dimensional part under ultraviolet light, or
an ultraviolet or infrared color.
8. The computer-readable medium of claim 6, wherein the outer layer
of the model has a non-uniform thickness.
9. A method comprising: receiving electronic data that describes a
three-dimensional part to be manufactured in an additive
manufacturing process; processing the electronic data to develop
instructions for creating a three-dimensional outer layer on an
exterior surface of the three-dimensional part, the outer layer
having a physical property that is not shared by a portion of the
part underlying the outer layer; and manufacturing the
three-dimensional part by additive manufacturing, including using
the instructions to manufacture the outer layer.
10. The method of claim 9 wherein the physical property is a
fluorescent color which contrasts with the underlying portion of
the part under ultraviolet light.
11. The method of claim 9 wherein the physical property is an
ultraviolet or infrared color.
12. The method of claim 9 wherein the physical property is
magnetism.
13. The method of claim 9 wherein the processing includes
developing the instructions based on an expected need for
post-processing selected portions of the exterior surface of the
part to remove surface imperfections.
14. The method of claim 13 wherein the outer layer has a physical
property that is not present on a portion of the part underlying
the outer layer.
15. The method of claim 13 wherein the developed instructions
specify manufacturing the outer layer on selected portions of the
exterior surface of the part, and the manufacturing the part
includes using the instructions to manufacture the outer layer on
the selected portions of the exterior surface of the part.
Description
BACKGROUND
[0001] Three-dimensional printed parts that have been manufactured
using an additive manufacturing process may contain surface
imperfections resulting from the additive manufacturing process.
These surface imperfections may be removed manually during
post-processing to create the final desired shape, texture, and/or
color. For example, a part manufactured using certain additive
manufacturing processes may have small artifacts or imperfections
on the exterior. These imperfections or irregularities may be
removed by chemical or mechanical means. Bead blasting is an
example of a mechanical post-processing method in which the
exterior surface of a manufactured part is ablated using a
pressurized stream of air or other fluid containing small, abrasive
particles or beads.
BRIEF DESCRIPTION OF THE DRAWINGS
[0002] Various examples will be described below referring to the
following figures:
[0003] FIG. 1 is a cross-view of a three-dimensional part made in
an additive manufacturing process in accordance with various
examples;
[0004] FIG. 2 is a cross-view of another three-dimensional part
made in an additive manufacturing process in accordance with
additional examples;
[0005] FIG. 3 is a cross-view of another three-dimensional part
made in an additive manufacturing process in accordance with
additional examples;
[0006] FIGS. 4A-4B are flow diagrams of methods in accordance with
various examples; and
[0007] FIG. 5 is a block diagram of an additive manufacturing
system in accordance with various examples.
DETAILED DESCRIPTION
[0008] An additive manufacturing system begins building a
three-dimensional (3D) part by receiving data comprising a 3D model
of the part to be manufactured. The model may contain surface color
information, for example, color information supplied by texture
mapping data in the 3D model. The manufacturing system processes
the 3D model data, which may include surface color information, to
determine the processing parameters of the part. For example, the
parameters may specify that a color layer be formed on the exterior
surface of one or more portions of the part.
[0009] While processing the 3D model, the system may also determine
where post-processing may occur on the surface of the part, for
example, ablating the surface using bead blasting to remove surface
irregularities in vertical walls. In those locations where such
surface removal is anticipated, the system may add an additional
thin layer having the same visible color as the underlying portion
of the part. This additional outer layer may include a visually
imperceptible property or mechanism to contrast the outer layer
from the underlying surface. For example, the thin outer layer may
be formed using an ultraviolet (UV) fluorescent color that appears
to be the same color as the underlying surface under ordinary white
light. However, when the 3D part is illuminated by UV light, those
areas where post-processing may occur are highlighted by the
contrasting fluorescent color. Likewise, the outer layer may be
formed using a material with magnetic properties that are not
visually perceptible, but which can be sensed using
instruments.
[0010] A human operator or automated device that is sensitive to
the properties of the contrasting outer layer is thus able to
remove or ablate the outer layer at predetermined locations until
the outer layer is no longer detectable. For example, the ablation
process may be stopped when a fluorescent color is no longer
observable or when magnetism is no longer detected. When the outer
layer is no longer detectable, the underlying portion of the 3D
part is considered complete or ready for further processing.
[0011] Prior solutions for manual bead blasting may require the
user to know what the part and final finish of the part should look
like and to make dynamic, real-time decisions about where and how
much bead blasting is needed, which may require skill and attention
by a highly trained operator. Other prior automated solutions for
bead blasting may simply process all portions of a 3D printed part
for a preset amount of time, which may not be ideal for all
surfaces on the part.
[0012] Examples in accordance with the present disclosure include
methods for manufacturing a 3D printed part with an outer layer
having a non-visually perceptible physical property. Additional
examples in accordance with the present disclosure include methods
for post-processing a 3D printed part using the outer layer to
guide the post-processing.
[0013] FIG. 1 shows a part 100 manufactured in a 3D printing
additive manufacturing process. In these processes, electronic
object model data describing the 3D part is supplied to the 3D
printer. The object model data is processed in the 3D printer to
develop instructions for manufacturing the part in an additive
manufacturing process. During this processing, the 3D printer may
also develop instructions for creating a thin outer layer 130. By
way of example, the instructions for creating the outer layer 130
may be developed by adding a thin outer layer 130 having a
thickness T.sub.2 of about 0.25 mm. In the example of FIG. 1, the
outer layer 130 has a uniform thickness T.sub.2 and is formed
around the entire exterior surface 110 of part 100. As discussed in
more detail below, other examples may provide an outer layer 130 at
selected portions of the exterior surface 110 and/or having a
varying thickness depending on the expected benefit for
post-processing at particular locations.
[0014] In one example, outer layer 130 is printed in an additive
manufacturing process with the same visible color as the underlying
portion of the part 100. For example, the outer layer 130 may
include a selected physical property that distinguishes the outer
layer 130 from the underlying portions of part 100. As discussed in
more detail below, this selected physical property may be a
fluorescent color that appears under UV light, a UV or near
infrared (IR) color outside the normal visible spectrum, or a
higher level of magnetism.
[0015] In one example, the outer layer 130 may be printed with a
fluorescent color that has the same visible color as the underlying
portion of the part 100 when viewed under normal white light (e.g.,
light having widely dispersed wavelengths predominantly in the
visible spectrum of 390-700 nm). When the fluorescent color in the
outer layer 130 is viewed under UV light (e.g., light having
wavelengths predominantly in the UV spectrum of 10-400 nm), the
color fluoresces and produces a color having a distinctly greater
brightness than the non-fluorescent color of the underlying portion
of the part 100. Thus, under white light, the outer layer 130 is
not visibly distinct from the underlying portions of the part 100.
However, under UV light, the outer layer 130 appears with a
visually distinctive brightness.
[0016] Post-processing the part 100 may involve ablating the
exterior using a bead blasting apparatus and the outer layer 130 to
remove surface imperfections. Here, the part 100 may be bead
blasted under UV light to precisely guide the desired location and
depth of the ablation process. The outside surface of the part 100
is ablated until the fluorescent outer layer 130 is no longer
observable under UV light. In this manner, ablating may be directed
at particular locations and not leave an excess of the outer layer
130, while also not removing underlying portions of the part 100,
either of which could adversely affect the appearance and
dimensional accuracy of the finished part 100.
[0017] The non-visually perceptible physical property of the outer
layer 130 may also be magnetism, or result from outer layer 130
including a UV or IR color. For example, when outer layer 130 is
applied in the additive manufacturing process, a small amount of
magnetic particles may be added to the build material.
Alternatively, the magnetic property may be supplied in the fusing
agent, other build components, or by other means. The outer layer
130 may thus be detected using a magnetic sensor and the ablation
process more precisely guided in a manner similar to using a
fluorescent color, as discussed above.
[0018] As noted, outer layer 130 may also be formed using a color
that appears visually the same color as the underlying part 100,
but which also includes a reflective UV or IR color component. As
used herein, IR colors are those having wavelengths predominantly
in the IR spectrum of 700-1,000 nm. These UV and IR colors may be
detected using an image sensor. For example, most image sensors
manufactured using a charge-coupled device (CCD) or a complimentary
metal-oxide semiconductor (CMOS) device are able to sense colors in
a range of wavelengths from 350 nm to 1,000 nm (which includes both
UV and IR light).
[0019] When the outer layer 130 includes a UV or IR color, the
outer layer 130 appears as the same visible color as the underlying
portions of the part 100. However, when the outer layer 130 is
viewed using an image sensor, the UV or IR wavelengths are detected
and may be highlighted for a user. In this manner, the outer layer
130 may be detected by an operator 100 using an image sensor and
the ablation process more precisely guided in a manner similar to
ablation using a fluorescent color, as discussed above.
[0020] Alternatively, the non-visually perceptible physical
property of the outer layer 130 may be used in automated or
partially automated post-processing. For example, the part 100 may
include an outer layer 130 having an IR color component. The part
100 may be mounted on a three-axis gimbal that is controlled by an
automated bead blasting machine. The bead blasting machine may
include an image sensor which continuously detects an image of the
surface of the part 100 at the point where the stream of beads
impacts the surface. The bead blasting process continues at this
location on part 100 until the sensed image no longer contains IR
color, whereupon the part 100 is rotated on the gimbal mount to a
new location that does contain IR color. When the IR color is no
longer detected by the image sensor, post-processing is
complete.
[0021] FIG. 2 illustrates a part 100 that includes a color layer
120 on the exterior surface 110. The color layer 120 may be
specified as part of the electronic data provided to the printer to
describe the 3D model of the part, for example, a texture map.
Alternatively, instructions for the color layer 120 may be
developed by specifying a single color, by manual data input on the
3D printer, or by other means. In these examples, outer layer 130
is created on top of the color layer 120.
[0022] The process of developing instructions to create the outer
layer 130 in the 3D printer may account for the additional
thickness T.sub.1 of any color layer 120. By way of example,
thickness T.sub.1 of color layer 120 may be 0.75 mm, in which case
the outer layer 130 may be created at a distance of 0.75 mm from
the surface 110 of part 100. Under these circumstances, the visible
color of the outer layer 130 may match the visible color of the
color layer 120. In addition, the non-visually perceptible physical
property of the outer layer 130 differs from this same property of
the color layer 120. For example, the fluorescent color of the
outer layer 130 may differ from any fluorescence emitted by the
color layer 120. Similarly, if magnetism is used as the physical
property, the magnetism of the outer layer 130 may differ from the
magnetism of the color layer 120.
[0023] The method of post-processing the part 100 illustrated in
FIG. 2 is much the same as post-processing the part 100 as
illustrated in FIG. 1. The post-processing, such as ablation, may
continue while the human operator or automated apparatus senses the
non-visually perceptible physical property of the outer layer 130.
The post-processing may stop when the non-visually perceptible
physical property is no longer detected. When the non-visually
perceptible physical property is no longer detected, the color
layer 120 would remain on the exterior surface 110 of part 100.
With traditional post-processing that does not use an outer layer
130, there may exist a risk that post-processing would ablate
through the color layer 120, revealing the underlying portions of
part 100 which may have a different color. Under those
circumstances, such a visible flaw may suggest rejecting part 100.
Using outer layer 130 reduces the risk of exposing underlying
portions of part 100 and increases the likelihood that the finished
part 100 will more closely match the dimensions and color of the
model supplied to the 3D printer.
[0024] FIG. 3 illustrates an alternative example of a part 100 with
an outer layer 130 that is useful for guiding post-processing to
remove surface imperfections or irregularities that are predictable
or inherent in a particular additive manufacturing process. By way
of example vertical walls may often contain small printing
artifacts more so than horizontal surfaces. Certain types of
additive manufacturing processes may be inherently predisposed to
leaving surface artifacts or imperfections at certain known
locations on the surface of a part 100 manufactured in the process.
The 3D printer may use these inherent characteristics, together
with the data describing the 3D model of the desired part 100, to
develop instructions for creating an outer layer 130 at the known
locations where surface artifacts or imperfections are likely to
appear. The same process may be used to develop instructions for
creating an outer layer 130 with a varying thickness. For example,
the outer layer 130 may be thicker at locations where surface
artifacts or imperfections are expected to be deeper, and thinner
where the artifacts or imperfections are expected to be
shallower.
[0025] Referring to FIG. 3, part 100 has a sloping portion P.sub.1,
a vertical portion P.sub.2, and a horizontal portion P.sub.3, all
as specified in the electronic data supplied to the 3D printer for
describing the 3D model of part 100. When the electronic data is
processed to develop instructions for creating part 100 in the
additive manufacturing process, the 3D printer recognizes that
deeper surface artifacts are more likely to develop on vertical
portion P.sub.2, that shallower artifacts are likely to develop on
sloping portion P.sub.1, and that no artifacts are likely to
develop on horizontal portion P.sub.3. Thus, the 3D printer
develops instructions to create an outer layer 130 with a greater
thickness T.sub.5 at the vertical portion P.sub.2, a shallower
thickness T.sub.3 at the sloping portion P.sub.1, and a very small
or no thickness T.sub.4 at the horizontal portion P.sub.3. As with
the other examples, outer layer 100 is created in the additive
manufacturing process with a physical property that is not present
on the underlying portions of part 100, e.g., a fluorescent color,
a UV or IR color, or magnetic properties.
[0026] When the part 100 illustrated in FIG. 3 has completed the
additive manufacturing process, manual or automated post-processing
may occur as with the preceding examples. The physical property in
outer layer 100 guides the location and amount or duration of
post-processing desired to create a part 100 without surface
artifacts or imperfections, while also having accurate dimensions
as originally specified in the electronic data describing the 3D
model.
[0027] FIGS. 1-3 depict manufactured parts, but the depictions in
these figures are also illustrative of the 3D models that may be
used to manufacture the parts described herein. As such, separate
drawings of 3D models are not provided.
[0028] FIG. 4A is a flow diagram of a method 400 in accordance with
various examples. The method 400 begins by receiving electronic
data that describes a three-dimensional part to be manufactured in
an additive manufacturing process (block 402). As explained, such
electronic data may include, for instance, texture data. The method
400 continues by processing the electronic data to develop
instructions for creating a 3D outer layer on an exterior surface
of the 3D part (block 404). The outer layer has a physical property
that is not shared by a portion of the part underlying the outer
layer (block 404). Examples of such a physical property are
provided above. The method 400 then includes manufacturing the 3D
part by additive manufacturing, including using the instructions to
manufacture the outer layer (block 406). The method is then
complete.
[0029] FIG. 4B depicts a flow diagram of a method 450 that is a
variation of method 400. The method 450 comprises receiving
electronic data that describes a three-dimensional part to be
manufactured in an additive manufacturing process, where the
physical property is a fluorescent color which contrasts with the
underlying portion of the part under ultraviolet light, an
ultraviolet or infrared color, or magnetism (block 452). The
physical property is not present on a portion of the part
underlying the outer layer (block 452). The method 450 then
includes processing the electronic data to develop instructions for
creating a three-dimensional outer layer on an exterior surface of
the three-dimensional part, with the outer layer having a physical
property that is not shared by a portion of the part underlying the
outer layer (block 454). The processing includes developing the
instructions based on an expected need for post-processing selected
portions of the exterior surface of the part to remove surface
imperfections (block 454). The developed instructions specify
manufacturing the outer layer on selected portions of the exterior
surface of the part (block 454). The method 450 then includes
manufacturing the three-dimensional part by additive manufacturing,
including using the instructions to manufacture the outer layer
(block 456). The manufacturing includes using the instructions to
manufacture the outer layer on the selected portions of the
exterior surface of the part (block 456). The method is then
complete.
[0030] FIG. 5 depicts a block diagram of an additive manufacturing
system 500. The system 500 may perform some or all of the actions
described above, including the generation of 3D models that
describe 3D parts and 3D outer layers adjacent to such parts, as
well as the manufacture of parts consistent with such models. In
some examples, the system 500 comprises a processor 502, a
computer-readable medium (e.g., storage) 504, and additive
manufacturing components (e.g., print beds, extruders, etc.) 512.
The storage 504 may store electronic data 506, such as the
electronic data described above; one or more 3D models 508, such as
the 3D models described above; and executable code 510, which, when
executed by the processor 502, may cause the processor 502 to
perform some or all of the actions attributed herein to the
processor 502 and/or, more generally, to the additive manufacturing
system 500.
[0031] The examples discussed above enhance various additive
manufacturing processes by facilitating simpler and more precise
post-processing, whether post-processing is automated or performed
manually. When manual post-processing is employed, the examples
discussed above may not benefit from advanced knowledge of the
final dimensions of the manufactured part, and they may not benefit
from a high level of skill and attention by a highly trained
operator as with prior art solutions.
[0032] The above discussion is meant to be illustrative of the
principles and various examples of the present disclosure. Numerous
variations and modifications will become apparent to those skilled
in the art once the above disclosure is fully appreciated. It is
intended that the following claims be interpreted to embrace all
such variations and modifications.
* * * * *