Note: Descriptions are shown in the official language in which they were submitted.
METHOD AND APPARATUS FOR ADDITIVE
MECHANICAL GROWTH OF TUBULAR STRUCTURES
[001a] The present invention relates generally to additive manufacturing and
specifically
to additive mechanical growth of tubular structures.
BACKGROUND
[001b] Additive manufacturing and 3D printing methods and devices are
expanding.
Innovations are occurring in materials used, systems of delivery, and
applications.
[002] The most popular 3D printers are appliances about the size of a
microwave. They
are limited in a few ways. Typically, they can only print one material at a
time, and the
build size is small, less than a cubic foot.
[003] Some additive manufacturing techniques utilize gantry systems or
mechanical
arms, which afford the ability to build larger objects. But these are still
limited to the size
and maneuverability of the system of delivery, the volume under the gantry
system or the
reach of the mechanical arm.
[004] There is a desire to build larger objects utilizing additive
manufacturing
techniques. A new method and device are needed to build these objects, but
also make
the objects strong enough to support the increased forces resulting from the
larger size.
BRIEF SUMMARY OF THE INVENTION
[005] In the following description, certain aspects and embodiments of the
present
disclosure will become evident. It should be understood that the disclosure,
in its
broadest sense, could be practiced without having one or more features of
these aspects
and embodiments. It should also be understood that these aspects and
embodiments are
merely exemplary.
[006] Enclosed are descriptions for a new method and apparatus for the
extrusion of
tubular objects. It affords the construction of large-scale objects with a
boundless build
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area, by utilizing the product for support and eliminating the need for an
external
positioning system.
[007] Certain embodiments utilize an extrusion method of additive
manufacturing. For
example, in certain embodiments, an extruder is placed inside a mobile print
head that
utilizes the cured extruded material as support. The print head may be linked
to at least
one material source. For example, the linkage between the print head and the
at least
one material source may be a hose. The length of the hose may allow for
greater range
of the print head. The hose may range from a few inches to hundreds of feet in
length,
allowing flexibility in size and applications.
[008] In certain embodiments, a base station may be positioned at one end of
the
hose. The base station may include, for example, a host computer, power
supply, and
extrusion materials for building objects.
[009] In certain embodiments, a print head may be situated at one end of the
hose.
The print head may be positioned at the end of the hose opposite the base
station. The
print head may comprise one or more nozzles for extruding at least one
material and a
means of stabilization and propulsion.
[010] Extrusion materials travel through the hose to the print head, where
they are
extruded through the multiple nozzles. Certain embodiments of this disclosure
have a
plurality of nozzles, which may be configured, for example in a circular
formation. In
addition to a circle, nozzles may be arranged to form a rectangle, octagon, or
square.
Any polygonal formation of nozzles is envisioned. At least one material is
extruded
through the nozzles, forming a tubular shaped object, called an extrusion
tube. The
tube grows in length as the print head continues extruding material while
moving in the
opposite direction of the extrusion.
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[011] The print head includes a means of stabilization and propulsion
relative to the
extrusion tube. Instead of relying on an external means, such as a gantry
system or a
mechanical arm, the print head utilizes the extrusion tube to provide a
foundation for
stability and propulsion. Several methods are available, for example,
including a motor
and a series of wheels that grip the inside of the hardened extrusion tube.
The wheels
may propel the print head while simultaneously extruding material and creating
the
extrusion tube.
[012] The print head may extrude through the one or more nozzles at the
same rate,
forming a straight extrusion tube. In certain embodiments, however the print
head varies
the extrusion rate of the nozzles, in order to create, for example, arcs,
turns, and
complicated objects. The materials extruded may comprise continuous
composites,
which provide added strength, allowing extrusion tubes to grow into free space
opposed
to gravity. This affords horizontal, inverted, and complex shaped extrusion
tubes.
[012a] According to an aspect of an embodiment, there is provided an additive
manufacturing system, comprising: a head having at least one nozzle that
discharges a
tubular shaped product, wherein the at least one nozzle is arranged around a
perimeter of
the tubular shaped product; and a propulsion system configured to be supported
by the
tubular shaped product and to propel the head during discharge of the tubular
shaped
product.
[012b] In an embodiment, the tubular shaped product is additively manufactured
from: a
curable matrix material; and a solid strand material at least partially
encased in the
curable matrix material. In another embodiment, the head includes at least one
curing
device configured to cure the curable matrix material in the tubular shaped
product as the
tubular shaped product discharges from the head. In yet another embodiment,
the at
least one curing device is further configured to cure the curable matrix
material at a point
between the at least one nozzle and the propulsion system.
[012c] According to another aspect of an embodiment, there is provided an
additive
manufacturing system, comprising: a head having at least one nozzle configured
to
discharge a tubular shaped product; a propulsion system configured to be
supported by
the tubular shaped product and to propel the head during discharge of the
tubular shaped
product; and a base station connected to at least one of the head and the
propulsion
system, the base station configured to supply at least one of power, control
communications, and material to the at least one of the head and the
propulsion system,
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wherein: the base station includes a controller configured to control
operation of the head;
the at least one nozzle of the head includes a plurality of nozzles arranged
around a
perimeter; and the controller is configured to selectively adjust discharge
from at least one of
the plurality of nozzles to cause the tubular shaped product to turn away from
a current
trajectory.
[012d] According to yet another aspect of an embodiment, there is provided an
additive
manufacturing system, comprising: a head having at least one nozzle configured
to
discharge a tubular shaped product, wherein the at least one nozzle is
arranged around a
perimeter of the tubular shaped product; at least one gripping device
configured to engage a
wall of the tubular shaped product and propel the head during discharge; and a
base station
connected to the head at a side opposite the at least one gripping device, the
base station
configured to supply at least one of power, control communications, and
material to the
head.
BRIEF DESCRIPTION OF THE DRAWINGS
[13] Figure 1 is a perspective view of a print head connected to a base
station by a
hose.
[14] Figure 2A is a perspective view of a print head with wheel system.
[15] Figure 2B is a bottom view of a print head with wheel system.
[16] Figure 3 is a perspective view of a print head with additional rolling
modules.
[17] Figure 4 provides perspective views of several means of stabilization
and
propulsion.
[18] Figure 5 shows perspective and cross section views of a straight
extrusion tube and
a mesh semi-tube.
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[019] Figure 6 is a perspective view of a starter piece with twelve anchors
and ten print
heads printing extrusion tubes.
[020] Figure 7 is a perspective view of three alternative extrusion tube
shapes.
[021] Figure 8 is a perspective view of three extrusion tubes resulting from
alternative
nozzle configurations.
[022] Figure 9 shows a perspective view of a truss detail and a front view of
a truss
comprised of three rectangular extrusion tubes.
[023] Figure 10A is perspective view of a boat hull frame.
[024] Figure 10B is a front view of a boat hull frame.
[025] Figure 11 is a perspective view of two extrusion tubes serving as
infrastructure.
[026] Figure 12A is a perspective view of an alternative embodiment of a base
station.
[027] Figure 12B is a perspective view of an alternative embodiment of a base
station
extruding six extrusion tubes from a starter piece.
DETAILED DESCRIPTION OF THE INVENTION
[028] Enclosed are embodiments for a new method and apparatus for additive
manufacturing. See Figure 1. The basic components of the apparatus may
include, for
example, a print head 101, a hose 102, and base station 103.
[029] Figures 2A and 2B show an exemplary print head. The perimeter of the
print
head may comprise one or more individual nozzles 201, which extrude a curable
matrix
material. The curable matrix materials may reside in reservoirs or spools in
the base
station. The curable materials may include, for example, composites comprised
of a
solid strand reinforcement material and a curable liquid matrix material.
Uniform
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curable matrix material without reinforced composites is also envisioned. Each
nozzle
extrudes the curable matrix material forming an individual path. In composite
paths, the
solid strand material is completely encased in the curable matrix material and
is aligned
coaxially with the path. Collectively, extrusions of all paths from the one or
more
nozzles form a cured tubular shape called an extrusion tube.
[030] In certain embodiments, the print head comprises nozzles situated in a
fixed
direction. In still other embodiments, however, the print head may include
articulating
nozzles, capable of increasing or decreasing the diameter of an extrusion
tube, as well
as moving side to side to create semi tubes.
[031] Certain embodiments of the present disclosure also have a means for
curing the
curable matrix material. For the purposes of this application, curing means
the
hardening of material. This could be, for example, a phase change from liquid
to solid,
the binding of solid powder particles, or the fusion of multiple solid
materials into one.
The means for curing may vary depending on the composition of the curable
matrix
material. In some instances, the means for curing might be inherent as a
function of
time or ambient temperature. Certain embodiments may utilize a photopolymer
resin,
which is curable by ultraviolet light. In these embodiments, the print head
may include a
UV light source illuminating out towards the extruded paths from one or more
LED lights
202. This ultraviolet light cures the paths soon after extrusion from the one
or more
nozzles. An alternative embodiment of the means for curing may utilize heat in
the case
of thermoplastic material. Other alternative means of curing may include, for
example,
chemical curing agents, cooling, high-powered lasers, and sonication, which is
the use
of sound waves.
[032] In embodiments extruding composite materials comprising a solid strand
material
encased within the curable matrix material, the print head also may include a
means of
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feeding the solid strand material, such that the rate of feeding the solid
strand material
is coordinated with the rate of extruding the curable matrix material.
[033] The print head includes a means of stabilization and propulsion. In
certain
embodiments, the print head may include, for example, a wheel system with a
rotating
wheelbase 203 and a series of wheels on tension loaded hinges 204. Additional
components in the print head may include, for example, one or more motors for
rotating
the wheelbase, rotating each individual wheel, and maneuvering a multi-
directional
hinge 205 between the wheelbase and the print head housing. A ball joint is
one
example of a multi-directional hinge. Some embodiments of the print head
contain a set
of four wheels spaced, for example, approximately 90 degrees apart. Other
embodiments may have more or less wheels as needed.
[034] Alternative embodiments of the print head may include sensors to monitor
operations. For example, the print head may include accelerometers or
gyroscopes to
measure orientation, thermometers to measure temperatures, and pressure
sensors to
maintain optimal material flow.
[035] The print head's housing 206 may have a diameter equal to, or slightly
smaller,
than the exterior diameter of the extrusion tube. This configuration permits
the
extrusion of tubes adjacent to existing surfaces as well as other extrusion
tubes. The
print head may, for example, have a diameter of six inches, although those
skilled in the
art would understand that additional diameters may alternatively be
implemented. The
perimeter of the print head may be equipped with a single ring-shaped nozzle
or a
plurality of nozzles forming a ring.
[036] A hose 102 may extend from the top of the print head 101 and connect to
the
base station 103. The hose may be connected to the print head and the base
station
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with, for example, rotor couplings. This connection allows the hose to twist
as needed
during operation.
[037] The hose may be comprised, for example, of several lines between the
print
head and the base station: a power supply, an internal hose supplying curable
matrix
material, an internal hose feeding solid strand material, and electronic
communication
lines providing feedback to the host computer and allowing it to operate the
components
in the print head.
[038] An alternative embodiment of the print head may have the hose running up
through the bottom of the print head rather than out the top. In this
embodiment, the
length of the hose runs up through the extrusion tube to the print head.
[039] Some embodiments may limit the need for a hose. Instead of materials
residing
in reservoirs or spools in the base station, they may be contained in the
print head, or in
housing connected to the print head. An alternative embodiment is shown in
Figure 3.
This print head 301 shows two rolling modules 302, 303 attached to the print
head.
These modules may contain reservoirs for curable matrix material, spools of
solid strand
material, a power supply, and a host computer with remote control radio
communication
capability. These embodiments would not require a hose, and permit the
apparatus to
operate entirely autonomously.
[040] The base station 103 may provide a power supply and house a host
computer, a
reservoir of curable matrix material, and one or more pumps for moving the
material
through the hose to the print head. In embodiments extruding composite
materials, the
base station may also include a supply of solid strand material and motors to
feed it
through the hose. In some embodiments, the base station may also include an
air or
water compressor for providing pressure in the extrusion tube.
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[041] The base station is designed to be mobile, so an operator of the
apparatus may
construct extrusion tubes on site. In some embodiments additional mobility may
be
desired, and the base station may then be equipped with its own means of
mobility.
See Figure 12A for an example of a base station with caterpillar tracks 1201.
[042] The host computer controls a variety of operations, including, for
example, the
extrusion rate of materials, the feed rates of solid materials, the means for
curing, and
the propulsion of the print head.
[043] The host computer coordinates these activities to produce quality
extrusion tubes
with the aid of feedback from available sensors on the print head. In some
embodiments, the host computer may control multiple print heads
simultaneously.
[044] This disclosure eliminates the need for the customary means of
positioning a
print head. As previously explained, known systems for positioning a print
head
typically use a gantry system or mechanical arm. Instead of using a gantry
system or
mechanical arm, the print head of the present disclosure comprises a means of
stabilization and propulsion. The means stabilize the print head in position
for extruding
while also propelling the print head forward. Several alternative systems
providing
means of stabilization and propulsion are possible: wheel, pig, caterpillar,
inchworm,
screw, walking, wall press, or magnet. See Figure 4.
[045] As shown in Figure 2A, a wheel system may extend from the bottom of the
print
head. Multiple sets of wheels may be connected to the print head via a shaft
equipped
with a multi-directional hinge. The wheels may be pressed against the inside
of the
extrusion tube, securing the print head in position. The wheels rotate in a
coordinated
manner, propelling the print head as it extrudes.
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[046] Figure 4 depicts an embodiment of a wheel system 401. Caterpillar
systems 402
function similarly to wheels systems, and simply replace the wheels with
caterpillar
tracks.
[047] In some embodiments, it may be desirable to increase the strength of the
wheel
system in order to better stabilize and propel the print head. Multiple sets
of wheels
may be added in succession behind the first set. Figure 3 shows a print head
with two
additional rolling modules 302, 303. Instead of these modules representing
base station
components as described above, each may be a functioning wheel system, capable
of
pressing the inside of the extrusion tube for stability and propelling the
print head
forward in a coordinated fashion.
[048] A pig system 403 may utilize pneumatic or hydraulic pressure to propel
the print
head forward. The pig may be attached to the print head with a multi-
directional hinge.
It may function as a tight fitting plug inside the extrusion tube. Gas or
liquid may be
pumped into the extrusion tube, creating pressure to propel the print head
forward. This
embodiment requires the addition of compressors and pumps, and hoses supplying
the
gas or liquid to the extrusion tube cavity. The supply may come, for example,
through a
print head valve, the base station, or through a valve opening somewhere on
the
extrusion tube. As the extrusion tube grows, the controlled pressure builds in
the tube,
forcing the print head to move at the same rate as the rate of extrusion. A
pig system
may be desirable for large straight tubes.
[049] Alternative means of stabilization and propulsion provide increased
functionality
for specific applications. The inchworm system 404 is useful for very small
tubes,
where the diameter might be impractical for a wheel system or other moving
parts. The
screw system 405 provides a rotation to the print head as it moves forward,
which would
create spiraling extrusion tubes. Wall press systems 407 provide a means of
increased
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stability, which may be useful when printing extrusion tubes vertically and
opposed to
gravity. Walking systems 406 provide articulating legs that might better
navigate
complicated extrusion tubes. Magnet systems 408 place a magnet inside the
extrusion
tube, and propel the print head forward by introducing an electromagnetic
field from an
external source moving along the extrusion tube. Magnetic systems may operate
best
in high-speed applications.
[050] These means of propulsion are generally referred to as pipe crawlers,
and are
used to inspect existing pipes, or drill tunnels. Instead of a equipping these
pipe
crawlers with inspection sensors or drill bits, a print head may be attached
via an
articulating joint, creating a pipe crawler that stabilizes a print head and
prints its own
pipe to crawl through.
[051] See Figure 5 for an example of a straight extrusion tube 501. To create
an
extrusion tube, the print head may extrude curable matrix material through
each of the
one or more nozzles at a coordinated rate. The extrusion tube is cured soon
after
extrusion, at a point between the nozzles and means of stabilization and
propulsion. It
is important that curing is done clear of the nozzles to prevent plugging the
print head.
The wheels 204 press out against the inside of the cured extrusion tube with
enough
force to stabilize the print head. As the tube extrudes, the wheels rotate at
the same
rate, lifting the print head. This procedure continues throughout the length
of the
extrusion tube, with the print head moving in coordination with the rate of
extrusion, and
continuously gripping the most recently cured portion of the extrusion tube.
[052] The method of printing extrusion tubes begins on an anchor with a
similar size
and shape to the extrusion tube. Figure 6 shows a starter piece 601 for
anchoring
extrusion tubes vertically or horizontally. This exemplary starter piece has
twelve
anchors 602, with ten print heads 603 utilizing ten of the anchors. The print
heads'
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means of stabilization and propulsion are placed inside the anchors, which
hold the print
heads in place so that the perimeters of the print heads line up with the
edges of the
anchors. The initially extruded curable matrix material may attach directly to
the edge of
the anchors where it is cured. The printing process continues as if the anchor
were
simply an extension of the extrusion tube.
[053] The anchors in Figure 6 may be attached to a starter piece 601 that will
be
incorporated into a final product. The anchor may also be the end of another
existing
extrusion tube. In some embodiments, a temporary anchor may serve to start an
extrusion tube, which is then manually cut away after the extrusion process is
complete.
[054] The present disclosure is directed to the creation of extrusion tubes
comprising a
curable matrix material, and extrusion tubes of composite materials comprising
a
curable matrix material and a solid strand reinforcement material. The curable
matrix
material may be stored in a reservoir in the base station. In some embodiments
the
curable matrix material may be stored in a reservoir attached directly to the
print head.
Envisioned curable matrix materials, for example, may include ultraviolet
photopolymers
or thermoplastics, although those skilled in the art will appreciate that
additional curable
matrix materials may be used.
[055] Ultraviolet photopolymers are uniquely blended to cure under ultraviolet
light.
Photopolymers include, for example, acrylates, monomers, oligomers,
bismaleimides,
and thermosetting epoxies.
[056] Thermoplastics are solid plastics that are heated to melt before
extrusion.
Thermoplastics include, for example, polylactic acid (PLA), acrylonitrile
butadiene
styrene (ABS), cellulose, polyether ether ketone (PEEK), polyetherimide (PEI),
polyethylene terephthalate (PET), and nylon. Thermoplastics require a spool of
material
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instead of a reservoir, and an alternative embodiment for the print head may
include a
heat source to melt the material prior to extrusion. In certain embodiments
thermoplastics may be combined with a filler to form a heterogeneous
composite.
Envisioned fillers include, for example, ceramic powder, metal powder, sand,
glass
powder, and chopped fiber.
[057] Alternative embodiments may utilize a laser sintering process, where the
curable
matrix material is a powder sprayed out of the nozzle. Powders provide a wide
range of
materials including the photopolymers and thermoplastics listed above, and
also metals,
alloys, ceramics.
[058] Certain embodiments of the present disclosure extrude composite paths,
utilizing
at least two materials, a matrix of liquid curable material surrounding a
solid strand
material. In these embodiments, the solid materials are stored on spools
either in the
base station or attached to the print head. Examples of solid strand materials
include
cotton, hemp, jute, flax, ramie, rubber, sisal bagasse, ground wood, thermo
mechanical
pulp, bleached kraft, unbleached kraft, sulfite, silk wool, fur, spidroins,
chrysotile,
amosite, crocidolite, tremolite, anthophyllite, actinolite, metal, metal
alloys, aramid,
carbon fiber, carbon nanotube fiber, silicon carbide, fiberglass,
petrochemical, or
polymer. Those skilled in the art will understand that any solid strand
material may be
used, and may include tubular strands, meshes or fiber tows.
[059] The composite may be any combination of photopolymer or thermoplastic
with a
solid strand. For example, one possible composite is an ultraviolet
photopolymer
comprising monomers combined with a solid strand of 3k carbon fiber tow
twisted every
two inches. The photopolymer should have an appropriate viscosity to adhere to
the
carbon tow during extrusion. For some applications it may be desired to print
some
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paths with photopolymer and others with thermoplastic. Any combination of the
above-
mentioned materials is envisioned.
[060] In some embodiments of the present disclosure, the speed for printing
composite
paths is 450 inches per minute, but faster or slower speeds may be desirable
depending
on the application.
[061] See Figure 5 for an example section of a composite extrusion tube 501,
and its
cross-section 502. The solid strand material 505 may be completely encased
within the
path. Composite paths may be desirable, as they may provide strength to the
finished
product, and stability during the manufacturing process.
[062] Paths may be comprised of several combinations of material. For example,
some paths may be a carbon fiber solid strand material and a photopolymer
resin as the
curable matrix material. This combination provides strength to each path and
the entire
extrusion tube. Another embodiment of a path's composition may have a solid
strand
material of conductive metal encased in fiberglass. This path composition
affords the
ability to create extrusion tubes with conductive properties. Those skilled in
the art
would understand that other functional paths may be implemented.
[063] The present disclosure affords the ability to make a wide variety of
tubular
shapes, including spirals, curves and angles. See Figure 7.
[064] The extrusion process performs in a similar way when creating a spiral
path 701,
but with the addition of a coordinated rotation between the means of
propulsion and the
print head. When using a wheel system for propulsion, a shaft 203 connecting
the
wheel system to the print head may spin continuously throughout the extrusion
process.
A spiral extrusion tube may supply even greater strength.
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[065] Composite extrusion tubes are strong enough to afford the printing of
straight
and spiral paths vertically, or in other directions. The print head may use
the wheel
system to grip the inside of the tube with enough force to stabilize it
against gravitation
forces regardless of the orientation; vertical, horizontal, inverted, or any
other three-
dimensional vector.
[066] Extrusion tubes may also make arcs and turns. A simple example is the
printing
of a tube at a right angle 702. The print head moves vertically and then
performs a 90-
degree turn. During the turn, each nozzle extrudes at variable coordinated
rates to
accomplish the turn. For example, when making a left turn, the nozzles on the
right side
will extrude at a greater rate than those on the left. As the angle of the
extrusion tube
changes direction, the multi-directional hinge adjusts, allowing the wheels to
grip the
previous portion of the tube while the print head is extruding in a slightly
altered
direction. The multi-directional hinge may adjust accordingly to create a
variety of
angles, and produce complicated extrusion paths, such as an s-curve 703.
[067] Figure 8 shows a variety of extrusion tubes with different nozzle
configurations.
In addition to a circle, nozzles may be arranged to form a rectangle 801,
octagon 802,
or square 803. Any polygonal formation of nozzles is envisioned.
[068] In some applications, it may be beneficial to cease extrusion of some
nozzles
during the formation of an extrusion tube for the formation of access holes or
meshes.
When an individual nozzle or group of adjacent nozzles stop and restart
extruding while
other nozzles extrude continuously, a hole will form in the extrusion tube.
These holes
may serve as access to the interior of the tube. A coordinated stop and start
of various
nozzles may form a mesh tube, requiring significantly less material to
construct.
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[069] In an alternative embodiment, the print head may be comprised of
articulating
nozzles, capable of moving and rotating 360 degrees. This affords the ability
for a
single print head to extrude tubes of varying diameters, or cross-sectional
areas for non-
circular tubes. As the nozzles move towards or away from the central access of
the
print head, the diameter of the tube will decrease or increase.
[070] Additionally, the nozzles may move from side to side, along the
perimeter of the
print head. This functionality may best be used when only some of the nozzles
are
extruding. See Figure 5 for an example cross-section 504 utilizing only a
portion of the
nozzles in the print head. This creates a semi-tube, where there are gaps in
between
each path. If the nozzles alternate side to side, the paths connect, forming a
mesh
semi-tube 503. This embodiment may allow for the printing of extrusion tubes
with less
material and increased strength.
[071] There are many practical applications for the mechanical growth of
extrusion
tubes. It provides the ability to print on site with relatively low equipment
requirements,
and in areas or ranges inaccessible to traditional additive manufacturing
positioning
systems. This method and apparatus is particularly useful for large-scale
construction
of buildings, bridges, and infrastructure, as well as water vessels and
satellites in zero
gravity. Several practical applications are listed below and those skilled in
the art will
appreciate a myriad of additional applications.
[072] Figure 9 shows a front view of a truss comprising three rectangular
extrusion
tubes 902 and a detail view 901 of how the three tubes connect to form the
truss. It is
possible to build complex and coordinated shapes with multiple extrusion
tubes. These
shapes may be built on site and added to a building, or they may be embedded
within
the building itself.
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CA 02994121 2018-01-29
WO 2017/019374 PCMJS2016/042908
[073] Figures 10A and 10B show a boat hull frame created from multiple
extrusion
tubes. Because of the elimination of a remote positioning system, boat hulls
of large
size are capable. The hollow tubes provide an additional means of buoyancy to
watercraft.
[074] Figure 11 shows an application for city infrastructure. Extrusion tubes
of custom
size and shape may serve as water, sewer, gas, or electric pipes.
[075] Figure 12A shows an alternative embodiment of the base station. This
example
base station is equipped with a means of mobility, caterpillar tracks 1201,
which may
allow the base station to move relative to the needs of the desired product.
Additionally,
Figure 12A depicts two print heads 1202 attached; however, it has the
availability for six
print heads, allowing the simultaneous printing of multiple extrusion tubes.
The base
station may also be equipped with anchors 1203 for starting extrusion tubes.
[076] Figure 12B shows a potential application of this alternative embodiment.
A
starter piece 1204 supplies six anchors to start six contiguous extrusion
tubes. As the
tubes grow, the base station moves with it, providing a potentially limitless
build space
with a relatively small machine.
[077] The claims are to be interpreted broadly based on the language employed
in the
claims and not limited to examples described in the present specification,
which
examples are to be construed as non-exclusive. Further, the steps of the
disclosed
methods may be modified in any manner, including by reordering steps and/or
inserting
or deleting steps. Accordingly, the disclosed embodiments are not limited to
the above-
described examples, but instead are defined by the appended claims in light of
their full
scope of equivalents.
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