U.S. patent application number 15/895142 was filed with the patent office on 2018-08-16 for multi-stage additive manufacturing system.
This patent application is currently assigned to CC3D LLC. The applicant listed for this patent is CC3D LLC. Invention is credited to Ryan C. Stockett, Kenneth Lyle Tyler.
Application Number | 20180229430 15/895142 |
Document ID | / |
Family ID | 63104949 |
Filed Date | 2018-08-16 |
United States Patent
Application |
20180229430 |
Kind Code |
A1 |
Tyler; Kenneth Lyle ; et
al. |
August 16, 2018 |
MULTI-STAGE ADDITIVE MANUFACTURING SYSTEM
Abstract
An additive manufacturing system is disclosed. The additive
manufacturing system may include a first print stage configured to
discharge a first type of composite structure. The additive
manufacturing system may also include a second print stage
configured to discharge a second type of composite structure. The
additive manufacturing system may further include a support
configured to move the first and second print stages.
Inventors: |
Tyler; Kenneth Lyle; (Coeur
d'Alene, ID) ; Stockett; Ryan C.; (Lebanon,
NH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CC3D LLC |
Coeur d'Alene |
ID |
US |
|
|
Assignee: |
CC3D LLC
Coeur d'Alene
ID
|
Family ID: |
63104949 |
Appl. No.: |
15/895142 |
Filed: |
February 13, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62459398 |
Feb 15, 2017 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B33Y 80/00 20141201;
B29C 64/245 20170801; B29C 64/241 20170801; B29C 70/384 20130101;
B33Y 30/00 20141201; B29C 70/207 20130101; B29K 2101/10 20130101;
H05B 2203/011 20130101; B29C 64/236 20170801; B29C 64/165 20170801;
B29C 64/209 20170801; B29C 64/291 20170801; B29L 2031/779 20130101;
B29L 2031/753 20130101; B33Y 10/00 20141201; H05B 3/286 20130101;
B29C 64/232 20170801; B33Y 70/00 20141201; B29C 70/885 20130101;
H05B 2203/014 20130101; B29K 2995/0007 20130101; B29C 64/393
20170801; C01B 32/194 20170801 |
International
Class: |
B29C 64/165 20060101
B29C064/165; B29C 64/393 20060101 B29C064/393; B33Y 10/00 20060101
B33Y010/00; B33Y 30/00 20060101 B33Y030/00; B29C 64/209 20060101
B29C064/209 |
Claims
1. An additive manufacturing system, comprising: a first print
stage configured to discharge a first type of composite structure;
a second print stage configured to discharge a second type of
composite structure; and a support configured to move the first and
second print stages.
2. The additive manufacturing system of claim 1, wherein: the first
type of composite structure is a tubular structure; and the second
type of composite structure is a skin discharged adjacent the
tubular structure.
3. The additive manufacturing system of claim 2, further including
a third print stage moveable by the support and configured to apply
a finish coat to the skin.
4. The additive manufacturing system of claim 3, wherein the first,
second, and third print stages together fabricate an entire
cross-section of a component.
5. The additive manufacturing system of claim 4, wherein the
component is a boat.
6. The additive manufacturing system of claim 5, wherein: the first
print stage is configured to anchor the first type of composite
structure to an end of a bulkhead; and the second print stage is
configured to extend the second type of composite structure over
the first type of composite structure and over an outer annular
surface of the bulkhead.
7. The additive manufacturing system of claim 6, wherein at least
one of the first and second print stages is further configured to
fabricate the bulkhead in-situ.
8. The additive manufacturing system of claim 6, wherein the
bulkhead is pre-fabricated.
9. The additive manufacturing system of claim 1, wherein: the first
print stage includes a plurality of first print heads chained to
each other; and the second print stage includes a plurality of
second print heads changed to each other.
10. The additive manufacturing system of claim 1, wherein the
second print stage follows behind the first print stage a distance
such that a matrix in the first type of composite structure is not
fully cured when the second type of composite structure overlaps
the first type of composite structure.
11. The additive manufacturing system of claim 1, further including
a controller in communication with the support and configured to
regulate movements of the first and second print stages.
12. A method of additive manufacturing, comprising: discharging
from a first type of print head a first type of composite
structure; and simultaneously discharging from a second type of
print head a second type of composite structure adjacent the first
type of composite structure.
13. The method of claim 12, wherein: the first type of composite
structure is a tubular structure; and the second type of composite
structure is a skin.
14. The method of claim 13, further including simultaneously
applying a finish coat to the skin.
15. The method of claim 14, wherein the tubular structure, skin,
and finish coat together form a cross-section of a boat.
16. The method of claim 15, further including: anchoring the
tubular structure to an end of a bulkhead; and extending the skin
over the tubular structure and over an outer annular surface of the
bulkhead.
17. The method of claim 16, further including discharging the
bulkhead from a composite material in-situ.
18. The method of claim 12, wherein: discharging from the first
type of print head includes discharging from a plurality of the
first type of print heads that have been chained to each other; and
discharging from the second type of print head includes discharging
from a plurality of the second type of print heads that have been
chained to each other.
19. The method of claim 12, further including moving the plurality
of the second type of print heads to follow behind the plurality of
the first type of print heads by a distance such that a matrix in
the first type of composite structure is not fully cured when the
second type of composite structure overlaps the first type of
composite structure.
20. A method of additive manufacturing, comprising: discharging a
plurality of composite tubes adjacent each other to form an
internal skeleton in a shape of a boat hull; and simultaneously
discharging a composite skin over the plurality of composite tubes,
wherein a matrix in the plurality of composite tubes is not fully
cured when the composite skin is discharged over the plurality of
composite tubes.
Description
RELATED APPLICATIONS
[0001] This application is based on and claims the benefit of
priority from U.S. Provisional Application No. 62/459,398 that was
filed on Feb. 15, 2017, the contents of which are expressly
incorporated herein by reference.
TECHNICAL FIELD
[0002] The present disclosure relates generally to a manufacturing
system and, more particularly, to a multi-stage additive
manufacturing system.
BACKGROUND
[0003] Pultrusion is a common way to manufacture composite parts.
During pultrusion manufacturing, individual fiber strands, braids
of strands, and/or woven fabrics are pulled from corresponding
spools into a resin bath and through a stationary die. The resin is
then allowed to cure and harden. Due to the pulling of the fibers
prior to curing, some of the fibers may retain a level of tensile
stress after curing is complete. This tensile stress can increase a
strength of the composite part in the direction in which the fibers
were pulled.
[0004] A vacuum-assisted resin transfer molding (VARTM) process is
commonly used to fabricate the skin of a large composite structure
(e.g., of a vehicle body), after an internal skeleton has already
been formed (e.g., via pultrusion). In a VARTM process, sheets of
fibrous material are manually pulled over the internal skeleton and
then tacked in place. The tacked material is then manually coated
with a liquid matrix (e.g., a thermoset resin or a heated
thermoplastic), covered with a vacuum bag to facilitate
impregnation of the liquid matrix, and allowed to cure and
harden.
[0005] Although pultrusion manufacturing and VARTM can be used
together to produce some large composite parts, they can also be
problematic. In particular, the VARTM-produced skin is often
attached to the pultruded skeletal components and/or reinforced via
metallic fasteners (e.g., screws, rivets, and clips). The use of
metallic fasteners can drive skeletal design and increase a weight
and cost of the part. In addition, the various components of the
large composite part may need to be joined to each other via
specially designed hardware, which can also be heavy and costly.
Further, a significant delay may be required between fabrication of
the internal skeleton and the skin, in order to allow for the
internal skeleton to fully cure. Finally, conventional pultrusion
and VARTM manufacturing processes may provide little flexibility in
the design and/or use of the composite part.
[0006] The disclosed additive manufacturing system is directed to
overcoming one or more of the problems set forth above and/or other
problems of the prior art.
SUMMARY
[0007] In one aspect, the present disclosure is directed to an
additive manufacturing system. The additive manufacturing system
may include a first print stage configured to discharge a first
type of composite structure. The additive manufacturing system may
also include a second print stage configured to discharge a second
type of composite structure. The additive manufacturing system may
further include a support configured to move the first and second
print stages.
[0008] In one aspect, the present disclosure is directed to a
method of additive manufacturing. The method may include
discharging from a first type of print head a first type of
composite structure. The method may also include simultaneously
discharging from a second type of print head a second type of
composite structure adjacent the first type of composite
structure.
[0009] In one aspect, the present disclosure is directed to another
method of additive manufacturing. This method may include
discharging a plurality of composite tubes adjacent each other to
form an internal skeleton in the shape of boat hull. The method may
also include simultaneously discharging a composite skin over the
plurality of composite tubes. A matrix in the plurality of
composite tubes may not be fully cured when the composite skin is
discharged over the plurality of composite tubes.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a diagrammatic illustration of an exemplary system
for additively manufacturing a composite part; and
[0011] FIGS. 2-4 are isometric illustrations of exemplary
applications of the system of FIG. 1.
DETAILED DESCRIPTION
[0012] FIG. 1 illustrates an exemplary system 10 for additively
manufacturing a composite component 12. System 10 may implement any
number of different additive processes during manufacture of
component 12. For example, component 12 is shown in FIG. 1 as being
manufactured via a first additive process (represented in the
lower-left of FIG. 1) and via a second additive process
(represented in the upper-right of FIG. 1). It should be noted that
the first and second additive manufacturing processes may be
performed simultaneously or consecutively, as desired. It should
also be noted that component 12 may be manufactured utilizing only
one of the first and second additive processes.
[0013] The first additive process may be a pultrusion and/or
extrusion process, which creates hollow tubular structures 14 from
a composite material (e.g., a material having a matrix and at least
one continuous reinforcement). One or more heads 16 may be coupled
to a support 18 (e.g., to a robotic arm) that is capable of moving
head(s) 16 in multiple directions during discharge of structures
14, such that resulting longitudinal axes 20 of structures 14 are
three-dimensional. Such a head is disclosed, for example, in U.S.
patent application Ser. Nos. 15/130,412 and 15/130,207, all of
which are incorporated herein in their entireties by reference.
[0014] Head(s) 16 may be configured to receive or otherwise contain
the matrix material. The matrix may include any type of liquid
resin (e.g., a zero-volatile organic compound resin) that is
curable. Exemplary matrixes include thermosets, single- or
multi-part epoxy resins, polyester resins, cationic epoxies,
acrylated epoxies, urethanes, esters, thermoplastics,
photopolymers, polyepoxides, thiols, alkenes, thiol-enes, and more.
In one embodiment, the pressure of the matrix inside of head(s) 16
may be generated by an external device (e.g., an extruder or
another type of pump) that is fluidly connected to head(s) 16 via
corresponding conduits (not shown). In another embodiment, however,
the pressure may be generated completely inside of head(s) 16 by a
similar type of device and/or simply be the result of gravity
acting on the matrix. In some instances, the matrix inside head(s)
16 may need to be kept cool and/or dark, in order to inhibit
premature curing; while in other instances, the matrix may need to
be kept warm for the same reason. In either situation, head(s) 16
may be specially configured (e.g., insulated, chilled, and/or
warmed) to provide for these needs.
[0015] The matrix stored inside head(s) 16 may be used to coat any
number of continuous reinforcements and, together with the
reinforcements make up walls of composite structures 14. The
reinforcements may include single strands, a tow or roving of
several strands, or a weave of many strands. The strands may
include, for example, carbon fibers, vegetable fibers, wood fibers,
mineral fibers, glass fibers, metallic wires, ceramic fibers,
basalt fibers, optical tubes, etc. The reinforcements may be coated
with the matrix while the reinforcements are inside head(s) 16,
while the reinforcements are being passed to head(s) 16, and/or
while the reinforcements are discharging from head(s) 16, as
desired. In some embodiments, a filler material (e.g., chopped
fibers, metallic or ceramic particles, etc.) may be mixed with the
matrix before and/or after the matrix coats the reinforcements. The
matrix, the dry reinforcements, reinforcements already coated with
the matrix, and/or the filler may be transported into head(s) 16 in
any manner apparent to one skilled in the art. The matrix-coated
reinforcements may then pass over a centralized diverter (not
shown) located at a mouth of head(s) 16, where the matrix is caused
to cure (e.g., from the inside-out, from the outside-in, or both)
by way of one or more cure enhancers (e.g., UV lights, ultrasonic
emitters, microwave generators, infrared heaters, chillers, etc.)
22.
[0016] In embodiments where component 12 is made up of multiple
structures 14, each structure 14 may be discharged adjacent another
structure 14 and/or overlap a previously discharged structure 14.
In this arrangement, subsequent curing of the liquid matrix within
neighboring structures 14 may bond structures 14 together. Any
number of structures 14 may be grouped together and have any
trajectory, shape, and size required to generate the desired shape
of component 12.
[0017] In some embodiments, a fill material (e.g., an insulator, a
conductor, an optic, a surface finish, etc.) could be deposited
inside and/or outside of structures 14, while structures 14 are
being formed. For example, a hollow shaft (not shown) could extend
through a center of and/or over any of the associated head(s) 16. A
supply of material (e.g., a liquid supply, a foam supply, a solid
supply, a gas supply, etc.) could then be connected with an end of
the hollow shaft, and the material forced through the hollow shaft
and onto particular surfaces (i.e., interior and/or exterior
surfaces) of structure 14. It is contemplated that the same cure
enhancer(s) 22 used to cure structure 14 could also be used to cure
the fill material, if desired, or that additional dedicated cure
enhancer(s) (not shown) could be used for this purpose. The fill
materials could allow one or more of structures 14 to function as
tanks, passages, conduits, ducts, etc.
[0018] The second additive manufacturing process may also be a
pultrusion and/or extrusion process. However, instead of
discharging hollow tubular structures 14, the second additive
manufacturing process may be used to discharge tracks, ribbons,
and/or sheets 23 of composite material (e.g., adjacent tubular
structures 14 and/or over other features of component 12). In
particular, one or more heads 24 may be coupled to a support 26
(e.g., to an overhead gantry) that is capable of moving head(s) 24
in multiple directions during fabrication of component 12, such
that resulting contours of component 12 are multi-dimensional
(e.g., three-dimensional).
[0019] Head 24 may be similar to head 16 and configured to receive
or otherwise contain a matrix material (e.g., the same matrix
contained within head 16 or a different matrix). The matrix stored
inside head(s) 24 may be used to coat any number of separate
reinforcements, allowing the reinforcements to make up centralized
cores of the discharging tracks, ribbons, and/or sheets 23. The
reinforcements may include single strands, a tow or roving of
several strands, or a weave of multiple strands. The strands may
include, for example, carbon fibers, vegetable fibers, wood fibers,
mineral fibers, glass fibers, metallic wires, optical tubes, etc.
The reinforcements may be coated with the matrix while the
reinforcements are inside head(s) 24, while the reinforcements are
being passed to head(s) 24, and/or while the reinforcements are
discharging from head(s) 24, as desired. The matrix, the dry
reinforcements, and/or reinforcements already coated with the
matrix may be transported into head(s) 24 in any manner apparent to
one skilled in the art. The matrix-coated reinforcements may then
pass through one or more circular orifices, rectangular orifices,
triangular orifices, or orifices of another curved or polygonal
shape, where the reinforcements are pressed together and the matrix
is caused to cure by way of one or more cure enhancers 22.
[0020] As described above, the first and second additive
manufacturing processes can be extrusion or pultrusion processes.
For example, extrusion may occur when the liquid matrix and the
associated continuous reinforcements are pushed from head(s) 16
and/or head(s) 24 during the movement of supports 18 and/or 26.
Pultrusion may occur after a length of matrix-coated reinforcements
is connected to an anchor (not shown) and cured, followed by
movement of head(s) 16 and/or head(s) 24 away from the anchor. The
movement of head(s) 16 and/or head(s) 24 away from the anchor may
cause the reinforcements to be pulled from the respective head(s),
along with the coating of the matrix material.
[0021] In some embodiments, pultrusion may be selectively
implemented to generate tension in the reinforcements that make up
component 12 and that remains after curing. In particular, as the
reinforcements are being pulled from the respective head(s), the
reinforcements may be caused to stretch. This stretching may create
tension within the reinforcements. As long as the matrix
surrounding the reinforcements cures and hardens while the
reinforcements are stretched, at least some of this tension may
remain in the reinforcements and function to increase a strength of
the resulting composite component 12.
[0022] Components fabricated via conventional pultrusion methods
may have increased strength in only a single direction (e.g., in
the single direction in which fibers were pulled through the
corresponding die prior to resin impregnation and curing). However,
in the disclosed embodiment, the increased strength in component 12
caused by residual tension within the corresponding reinforcements
may be realized in the axial direction of each of the
reinforcements. And because each reinforcement could be pulled in a
different direction during discharge from head(s) 16 and/or 24, the
tension-related strength increase may be realized in multiple
(e.g., innumerable) different directions.
[0023] Components fabricated via conventional pultrusion methods
may have strength increased to only a single level (e.g., to a
level proportionate to an amount in which the reinforcements were
stretched by a pulling machine prior to resin impregnation and
curing). However, in the disclosed embodiment, because the matrix
surrounding each reinforcement may be cured and harden almost
immediately upon discharge, the force pulling on the reinforcement
may be continuously varied along the length of the fiber, such that
different segments of the same reinforcement are stretched by
different amounts. Accordingly, the residual tensile stress induced
within each of the different segments of each different
reinforcement may also vary, resulting in a variable strength
within different areas of component 12. This may be beneficial in
variably loaded areas of component 12.
[0024] FIG. 2 illustrates a large-scale application of system 10.
In this application, a plurality of heads 16 are connected to work
together (e.g., in a chain configuration) in one or more stages of
fabrication, while a plurality of heads 24 are connected to work
together in one or more subsequent stages of fabrication. Within
each stage of fabrication, heads 16 and heads 24, within their
respective stage(s), may be located adjacent each other and
collectively moved, oriented, and/or positioned by a common support
18 and/or 26 during material discharge. In this way, a larger
portion (e.g., one or more layers of an entire cross-section) of
component 12 may be fabricated simultaneously.
[0025] For example, a first stage S.sub.1 involving multiple heads
16 may be used to fabricate adjacent tubular structures 14 that
make up a rough internal skeleton at a relatively fast rate. A
second stage S.sub.2 involving multiple heads 24 may follow behind
the first stage S.sub.1 and create finer (e.g., smaller and closer
together) constructions (e.g., a skin from fibers, ribbons and/or
sheets 23) with greater accuracy on top of the larger constructions
created by the first stage S.sub.1 (over structures 14). In one
embodiment, the second stage S.sub.2 may follow a distance D.sub.1
behind the first stage S.sub.1, such that the matrix discharged in
the first stage S.sub.1 is not yet fully cured (e.g., such that the
matrix is still tacky) when the matrix-coated reinforcements of the
second stage S.sub.2 are discharged adjacent structures 14. In this
manner, cross-linking between the internal skeleton of stage
S.sub.1 and the covering of stage S.sub.2 may be enhanced. It is
contemplated that any number of the first and second stages
S.sub.1, S.sub.2 may be used to fabricate a single structure (e.g.,
stages that create larger and smaller overlapping tubular
structures 14; stages that create thicker or thinner outer skins;
and/or stages that create intermediate skins), and that the stages
could be choreographed in any order.
[0026] In some embodiments, any number of third stages S.sub.3 may
follow behind the first and/or second stages S.sub.1, S.sub.2. In
these embodiments, the third stage S.sub.3 may be a finish stage
focused on creating a final surface texture, tint, and/or sealant
coat on top of structures 14 and/or the outer skin. For example,
the third stage S.sub.3 may provide for a layer of matrix-coated
chopped fibers, a layer of only matrix, a layer of paint, a layer
of insulation, a gel coat, a clear coat, etc. to be deposited onto
the materials discharging from stages S.sub.1 and/or S.sub.2. In
one embodiment, the third stage S.sub.3 may follow a distance
D.sub.2 behind the second stage S.sub.2, such that the matrix
discharged in the second stage S.sub.2 is fully cured when the
material(s) of the third stage S.sub.3 are discharged over the top
of the material(s) of the second stage S.sub.2. In the example of
FIG. 2, an entire boat hull may be created by the time the first,
second, and third stages S.sub.1, S.sub.2, S.sub.3 are
complete.
[0027] A similar large-scale embodiment (also associated with boat
fabrication) is illustrated in FIG. 3. The boat hull of this
embodiment may be fabricated in much the same manner as in the
embodiment of FIG. 2. However, in contrast the previous embodiment,
the boat hull of FIG. 3 may include internal bulkheads 30 that are
interspersed with tubular structures 14. It is contemplated that
bulkheads 30 may be prefabricated or fabricated in-situ, as
desired. For example, bulkheads 30 may be cut from wood, injection
molded from a thermoplastic (e.g., a fiber-reinforced
thermoplastic), and/or fabricated via the first and/or second
processes described above.
[0028] If fabricated separately, bulkheads 30 may be stood up and
moved to designated locations prior to the first stage S.sub.1
(described above) being initiated. Bulkheads 30 may then become
starting and/or ending anchor points (also described above) for
tubular structures 14. For example, as shown in FIG. 4, each
bulkhead 30 may be sandwiched and chemically bonded in place
between ends of opposing tubular structures 14. The skin may then
be formed fibers, ribbons, and/or sheets 23 over an outer annular
surface of bulkheads 30 during formation on top of tubular
structures 14. This may help create stiff connections between the
separate components.
[0029] If fabricated in-situ using the disclosed system 10,
bulkheads 30 may be formed from one or more tubular structures
(e.g., a single structure that extends the entire length) 14 and/or
fiber strands, ribbons, and/or sheets. Bulkheads 30 that are
fabricated in this manner may be only partially cured prior to
inclusion within the rest of the boat hull, so as to improve
bonding with the other tubular structures 14 and/or skin 14. It is
contemplated that additional tubular structures 14 could be
arranged as internal and/or external layers that pass over the
outside and/or inside of bulkheads 30, if desired. In one
embodiment, bulkheads 30 and/or tubular structures 14 are filled
with a water-resistant and buoyant material (e.g., foam).
INDUSTRIAL APPLICABILITY
[0030] The disclosed arrangement and design of system 10 may be
used to fabricate any multi-layer composite structure. The
disclosed system 10 may be particularly useful for fabricating larg
structures. System 10 may allow for rapid discharge of high volumes
of material, with strong bonds between the layers. And the layers
may have varied constructions (e.g., lattice-like skeletal layers,
skin layers, coatings, etc.), use different materials, and have
different sizes (e.g., thicknesses).
[0031] It will be apparent to those skilled in the art that various
modifications and variations can be made to the disclosed additive
manufacturing system. Other embodiments will be apparent to those
skilled in the art from consideration of the specification and
practice of the disclosed additive manufacturing system. It is
intended that the specification and examples be considered as
exemplary only, with a true scope being indicated by the following
claims and their equivalents.
* * * * *