U.S. patent application number 15/577755 was filed with the patent office on 2018-05-10 for 3d printing device and method.
The applicant listed for this patent is PHILIPS LIGHTING HOLDING B.V.. Invention is credited to Manuela LUNZ, Elise Claude Valentine TALGORN.
Application Number | 20180126620 15/577755 |
Document ID | / |
Family ID | 53365808 |
Filed Date | 2018-05-10 |
United States Patent
Application |
20180126620 |
Kind Code |
A1 |
TALGORN; Elise Claude Valentine ;
et al. |
May 10, 2018 |
3D PRINTING DEVICE AND METHOD
Abstract
The invention provides a 3D printing device (500) comprising a
printer nozzle (502) for depositing a material on a support
structure (550) for the formation of a 3D object (10), wherein the
printer nozzle (502) and the support structure (550) are arranged
to be translated relative to each other with a translation speed in
a translation direction (52, 62), and a vibration actuator arranged
for providing a vibrating motion (50, 60) of at least a first part
of the support structure (550) relative to the printer nozzle (502)
in a direction different from the translation direction (52,
62).
Inventors: |
TALGORN; Elise Claude
Valentine; (EINDHOVEN, NL) ; LUNZ; Manuela;
(EINDHOVEN, NL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
PHILIPS LIGHTING HOLDING B.V. |
EINDHOVEN |
|
NL |
|
|
Family ID: |
53365808 |
Appl. No.: |
15/577755 |
Filed: |
May 26, 2016 |
PCT Filed: |
May 26, 2016 |
PCT NO: |
PCT/EP2016/061922 |
371 Date: |
November 28, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B29C 48/147 20190201;
B33Y 30/00 20141201; B33Y 10/00 20141201; B29C 64/118 20170801;
B29C 64/245 20170801; B29C 64/209 20170801; B33Y 40/00
20141201 |
International
Class: |
B29C 47/00 20060101
B29C047/00; B29C 64/245 20060101 B29C064/245; B29C 64/118 20060101
B29C064/118; B29C 64/209 20060101 B29C064/209 |
Foreign Application Data
Date |
Code |
Application Number |
May 29, 2015 |
EP |
15169932.9 |
Claims
1. A 3D printing device comprising: a support structure, a printer
nozzle for depositing a material on the support structure for the
formation of a 3D object, wherein the printer nozzle and the
support structure are arranged to be translated relative to each
other with a translation speed in a translation direction, and a
vibration actuator arranged for providing a vibrating motion of at
least a first part of the support structure relative to the printer
nozzle in a direction different from the translation direction.
2. The 3D printing device according to claim 1, wherein the support
structure extends along a support structure plane, wherein the
translation direction is parallel to the support structure plane,
and wherein the vibrating motion is in a direction parallel to
and/or perpendicular to the support structure plane.
3. The 3D printing device according to claim 1, wherein the
vibrating motion has a vibration frequency and the printed material
has a width and wherein the width multiplied with the vibration
frequency divided by the translation speed is larger than 0.5.
4. The 3D printing device according to claim 1, wherein the
vibrating motion is in a direction perpendicular to the support
structure plane and has a vibration frequency, and the printed
material has a height and wherein the height multiplied with the
vibration frequency divided by the translation speed is smaller
than 0.5.
5. The 3D printing device according to claim 1, wherein the
vibrating motion has a vibration frequency larger than or equal to
10 Hz.
6. The 3D printing device according to claim 1, wherein the
vibration actuator is arranged to provide a first vibrating motion
of the first part of the support structure and a second vibrating
motion of a second part of the support structure, the second
vibrating motion being different from the first vibrating motion
with respect to frequency and/or amplitude.
7. The 3D printing device according to claim 1, wherein at least a
third part of the support structure is clamped to influence the
vibrating motion of the third part of the support structure.
8. The 3D printing device according to claim 1, wherein the
vibration actuator is arranged to provide the support structure
with a vibration pattern with a frequency and amplitude that varies
over the support structure.
9. The 3D printing device according to claim 1, further comprising
a processor arranged to control the vibrating motion of the support
structure and the relative translation of the printer nozzle and
the support structure.
10. The 3D printing device according to claim 1, wherein the
support structure comprises a vibration plate, the vibration
actuator being arranged to provide a vibrating motion to the
vibration plate.
11. The 3D printing device according to claim 1, the 3D printing
device comprising a plurality of vibration actuators.
12. A method for manufacturing a 3D object, comprising the steps
of: depositing a material from a printer nozzle on a support
structure while translating the support structure and the printer
nozzle relative to each other with a translation speed in a
translation direction, and vibrating at least a first part of the
support structure relative to the printer nozzle in a direction
different from the translation direction.
13. The method according to claim 12, wherein the frequency and/or
amplitude and/or the direction of the vibrating varies as a
function of time.
14. Computer-readable storage medium instructions that when
executed by at least one processor of a 3D printing device causes
the printing device to generate a 3D object, comprising:
instructions for depositing a material from a printer nozzle on a
support structure, instructions for generating a translating motion
of the support structure relative to the printer nozzle with a
translation speed in a translation direction, and instructions for
generating a vibrating motion of a part of the support structure
relative to the printer nozzle in a direction different from the
translation direction.
Description
FIELD OF THE INVENTION
[0001] The invention relates to a 3D printing device and 3D
printing method for manufacturing a 3D object.
BACKGROUND OF THE INVENTION
[0002] Fused deposition modeling (FDM) is known in the art.
EP0833237 describes for example an apparatus incorporating a
movable dispensing head provided with a supply of material which
solidifies at a predetermined temperature, and a base member, which
are moved relative to each other along X-, Y-, and Z-axes in a
predetermined pattern to create three-dimensional objects by
building up material discharged from the dispensing head onto the
base member at a controlled rate. The apparatus is preferably
computer driven in a process utilizing computer aided design (CAD)
and computer aided manufacturing (CAM) software to generate drive
signals for controlled movement of the dispensing head and base
member as material is being deposited, or dispensed.
Three-dimensional objects may be produced by depositing repeated
layers of solidifying material onto each other until the shape is
formed. Any material, such as self-hardening waxes, thermoplastic
resins, molten metals, two-part epoxies, foaming plastics, and
glass, which adheres to the previous layer with an adequate bond
upon solidification, may be utilized. Each layer base is defined by
the previous layer, and each layer thickness is defined and closely
controlled by the height at which the tip of the dispensing head is
positioned above the preceding layer. The base member is moved
laterally along X- and Y-axes of a base plane and the dispensing
head is moved perpendicular to the base plane along the Z-axis.
[0003] WO-2007050972 discloses a nozzle for extruding a material to
construct a structure, the nozzle having multiple outlets for
extruding material. To cause the material to flow more smoothly
through one or more of the outlets, a vibration-generating device
is mounted to the nozzle, and arranged to generate vibrations that
are perpendicular to the flow of material, parallel to the follow,
at another angle with respect to the flow, or at more than one
angle with respect to the flow.
[0004] Additive manufacturing (AM), or 3D printing, is a growing
field of materials processing. It can be used for rapid
prototyping, customization, late stage configuration, or making
small series in production.
[0005] The resolution of the filaments produced by present FDM
printers is limited by the diameter of the extruded filament which
is presently at least about 0.3 mm. In order to create feature
dimensions smaller than about 0.1 mm, for example a pattern on the
surface of the 3D object with relative small feature dimensions
(e.g. in order to increase roughness for an improved grip)
different manufacturing techniques are required, such as stereo
lithography which is limited to light-sensitive materials such as
photopolymers, e.g. acrylates. Furthermore, to achieve the smallest
resolution, which may be in the order of 0.1 mm along a plane of
the support structure (XY-plane) and in the order of 0.02 mm
perpendicular to this plane (along the Z-axis), the speed of the
printing process needs to be lowered to enable, for example,
accurate alignment of the dispensing head with respect to a
previously or earlier printed layer. At a relatively high speed the
accuracy of the positioning of the dispensing head with respect to
the support structure is lower, especially in case of non-linear
movements of the dispensing head. Thus a lower speed is required to
increase the accuracy which leads to an increase in manufacturing
time of 3D printed objects.
SUMMARY OF THE INVENTION
[0006] Hence, it is an aspect of the invention to provide a 3D
printer and a method of manufacturing a 3D object that may provide
for relatively small feature sizes with a minimal influence on the
manufacturing time.
[0007] Hence, in a first aspect the invention provides a 3D
printing device, especially a fused deposition modeling 3D printing
device, wherein the 3D printing device comprises a support
structure, a printer nozzle for depositing a material on the
support structure for the formation of a 3D object, wherein the
printer nozzle and the support structure are arranged to be
translated relative to each other with a translation speed in a
translation direction, and a vibration actuator arranged for
providing a vibrating motion of at least a first part of the
support structure relative to the printer nozzle in a direction
different from the translation direction.
[0008] The terms "vibration" and "vibrating" refer to a periodic
motion in opposite directions, e.g. a movement back and forth or up
and down.
[0009] The 3D printing device is arranged to provide a basic
printed pattern through depositing or sespensing a material on a
support structure and (at the same time) provide relative
translation of the support structure with respect to the printer
nozzle. This relative translation may be a translation of only the
support structure, while the printer nozzle does not move and is
fixated at one position, or a translation of only the printer
nozzle, while the support structure does not move and is fixated at
one position, or a combination of movements of both the support
structure and the printer nozzle. A vibrating motion of at least a
first part of the support structure of the 3D printing device is
added, or superposed, to the relative translation. The vibrating
motion has a different direction with respect to the translation
direction. In this way a periodic pattern (through the vibrating
motion) is added to the basic (translation induced) pattern. Thus,
the vibrating motion provides for a second order (additional)
periodic movement of at least a part of the support structure next
to the (first order) relative translating movement of the support
structure with respect to the printer nozzle. As the vibrating
motion has (and is characterized by) a vibration frequency,
vibration amplitude and vibration direction, the dimension and the
form, or shape, of the pattern that is created at the first part of
the support structure (i.e. the part that experiences the vibrating
motion in addition to the translating movement) by depositing
material from the printer nozzle, is determined by at least a
combination of the translation speed, the vibration frequency and
the vibration amplitude and the normal printing parameters, such as
the speed of dispensing and the material that is dispensed). The
vibrating motion enables to create relatively small sized features
in addition to the basic pattern that is created by the (relative)
translating motion. In this way there is no need to decrease the
translation speed to provide for an improved accuracy or alignment
in order to create features with relatively small dimensions.
[0010] The pattern (or shape) of the printed or deposited material
will be periodic with a period that depends on the frequency of the
vibrating motion and will have an amplitude that depends on the
amplitude of the vibrating motion and on an angle between the
translation direction and the direction of the vibrating motion.
When the direction of the vibrating motion is in the same plane as
the relative translation of the printer nozzle and the support
structure, the amplitude of the pattern of the printed or deposited
material will be equal to the amplitude of the vibrating motion
times the absolute value of the sinus of the angle between the
translation direction and the direction of the vibrating motion. In
case the relative translation of the printer nozzle and the support
structure is in an X-Y plane and the direction of the vibrating
motion is perpendicular to the X-Y plane, thus in a direction along
the Z-axis (the Z-direction), then the pattern of printed or
deposited material will have an amplitude in the Z direction and
will be at maximum the amplitude of the vibrating motion. In this
case it is also possible that the pattern of printed or deposited
material will have an additional amplitude in the X-Y plane which
will have a smaller value than the amplitude in the
Z-direction.
[0011] The terms "3D printed object" or "3D object" refer to a
three-dimensional object obtained via 3D printing (which is an
additive manufacturing process), such as an object having a height,
a width and a length. The 3D (or 3DP) object can in principle be
any object that is 3D printable. It can be an item with a use
function or a purely decorative item. It can be a scale model of an
item such as a car, a house, a building, etc. Further, the 3D
object can be a piece or element for use in another device or
apparatus, such as a lens, a mirror, a reflector, a window, a
collimator, a waveguide, a color converting element (i.e.
comprising a luminescent material), a cooling element, a locking
element, an electrically conducting element, a casing, a mechanical
support element, a sensing element, etc. The 3D printed object
comprises 3D printed material.
[0012] Additive Manufacturing (AM) is a group of processes making
three-dimensional objects from a 3D model or another electronic
data source primarily through additive processes. Hence, the term
"3D printing" is substantially equivalent to "additive
manufacturing" or "additive manufacturing method". The additive
process can involve the binding of grains (via sintering, melting,
or gluing) or of layers of material (via successive deposition or
production of the layers, e.g. polymerization), etc. A widely used
additive manufacturing technology is the process known as Fused
Deposition Modeling (FDM). Fused deposition modeling (FDM) is an
additive manufacturing technology commonly used for modeling,
prototyping, and production applications. FDM works on an
"additive" principle by laying down material in layers; a plastic
filament or metal wire is unwound from a coil and supplies material
to produce a part. Possibly, (for thermoplastics for example) the
filament is melted and extruded before being laid down. FDM is a
rapid prototyping technology. Another term for FDM is "fused
filament fabrication" (FFF). Herein, the term "filament 3D
printing" (FDP) is applied, which is considered to be equivalent to
FDM or FFF. In general, FDM printers use a thermoplastic filament,
which is heated to its melting point and then extruded, layer by
layer (or in fact filament after filament) to create a
three-dimensional object. FDM printers can be used for printing a
complicated object. Hence, in an embodiment the method includes
production of the 3D printed object via FDM 3D printing.
[0013] The 3D printed object is especially (at least partly) made
from 3D printable material (i.e. material that may be used for 3D
printing).
[0014] Materials that may especially qualify as 3D printable
materials may be selected from the group consisting of metals,
glasses, thermoplastic polymers, silicones, etc. Especially, the 3D
printable material comprises a (thermoplastic) polymer selected
from the group consisting of ABS (acrylonitrile butadiene styrene),
Nylon (or polyamide), Acetate (or cellulose), PLA (poly lactic
acid), terephthalate (such as PET polyethylene terephthalate),
Acrylic (polymethylacrylate, Perspex, polymethylmethacrylate,
PMMA), Polypropylene (or polypropene), Polystyrene (PS), PE (such
as expanded-high impact-Polythene (or polyethene), Low density
(LDPE) High density (HDPE)), PVC (polyvinyl chloride)
Polychloroethene, etc. Optionally, the 3D printable material
comprises a 3D printable material selected from the group
consisting of Urea formaldehyde, Polyester resin, Epoxy resin,
Melamine formaldehyde, Polycarbonate (PC), rubber, etc. Optionally,
the 3D printable material comprises a 3D printable material
selected from the group consisting of a polysulfone, a polyether
sulfone, a polyphenyl sulfone, an imide (such as a poly ether
imide) etc.
[0015] In general these printable (polymeric) materials have a
glass transition temperature T.sub.g and/or a melting temperature
T.sub.m. The 3D printable material will be heated by the 3D printer
before it leaves the nozzle (assuming e.g. FDM) to a temperature of
at least the glass transition temperature, and in general at least
the melting temperature. Hence, in an embodiment the 3D printable
material comprises a thermoplastic polymer, such as having a glass
transition temperature T.sub.g and/or a melting point T.sub.m.
Specific examples of materials that can be used (herein) are e.g.
selected from the group consisting of acrylonitrile butadiene
styrene (ABS), polylactic acid (PLA), polycarbonate (PC), polyamide
(PA), polystyrene (PS), lignin, rubber, etc.
[0016] The term "printable material" may also refer to a plurality
of different 3D printable materials. The term "printable material"
especially refers to material that can be printed. For instance, in
the case of FDM the printable material may comprise a heated
polymer that is flowable. The printable material may be solid at
room temperature, but upon heating may become printable (i.e.
especially flowable). This heating is especially intended to
provide a flowable or printable material. In the case of inkjet
printing, the printable material may comprise particles in a liquid
(that may (be) evaporate(d) after deposition).
[0017] The term "printed material" especially herein refers to
printable material that has been deposited or printed. Hence, the
term "printable material" herein especially refers to the material
not (yet) dispensed, deposited or printed. The printing may,
amongst others, also include a curing. For instance, printed
material may be cured(e.g. by heating with light or another heat
source) after being deposited, followed by further printing on the
cured printed material.
[0018] In an embodiment of the 3D printing device according to the
invention, the support structure extends along a support structure
plane, wherein the translation direction is parallel to the support
structure plane, and wherein the vibrating motion is in a direction
parallel and/or perpendicular to the support structure plane. In
this way the vibrating motion provides for periodic features to be
created and added to the basic pattern of printed material in three
directions. The basic pattern is the pattern that is created by the
relative translation of the printer nozzle and the support
structure. The direction of the vibrating motion, and thus the
amplitude, may be parallel to the X-Y plane, i.e. the plane in
which the support structure extends, or in the Z-direction, i.e. in
a direction perpendicular to the support structure. The direction
of the vibrating motion may also vary in time, for example during a
first time period the vibrating motion is along a first direction
in the X-Y plane, during a second time period the vibrating motion
is along a second direction in the X-Y plane and during a third
time period the vibrating motion is along the Z-direction, or any
other combination. In this way relatively small size features may
be created in different directions.
[0019] In an embodiment of the 3D printing device according to the
invention, the vibrating motion has a vibration frequency, and the
printed material has a width, wherein the width multiplied with the
vibration frequency divided by the translation speed is larger than
0.5. The width is defined as the shortest distance of the printed
material along the XY plane, such as along the plane of the
translation direction and/or the plane of the support structure. It
can be calculated that the (periodic) pattern of printed (or
deposited) material has a period which is equal to the translation
speed divided by the frequency of the vibrating motion (in case the
printed material does not experience a vibrating motion there will
be no periodic pattern and hence no period). In general the pattern
period will be larger than zero, but a practical lower limit of the
pattern period may be 200% of the width of the printed material
(which is the width without the vibrating motion), because
otherwise e.g. part of the material from the back and forth
movement during the vibrating motion would be deposited in the same
location which may result in for example unwanted thickness
variations and in this way overlap of printed material during the
vibrating motion is avoided in this way and unwanted pattern
variations, such as interference patterns, are avoided. Combining
this results in that the width multiplied with the vibration
frequency divided by the translation speed should be larger than
0.5. For example, a printing speed of 100 mm/sec and a width of the
printed material of 0.3 mm results in a maximum frequency of the
vibrating motion of 167 Hz to achieve a pattern period of 0.6 mm
which is at minimum 200% of the width of the printed material (i.e.
twice the width).
[0020] In an embodiment of the 3D printing device according to the
invention, the vibrating motion has a vibration frequency, and the
printed material has a height, wherein the width multiplied with
the vibration frequency divided by the translation speed is smaller
than 0.5. In this case the vibration direction has an angle with
the support structure plane, e.g. is for example perpendicular to
the support structure plane. The height (or thickness or extension)
is defined as the shortest distance of the printed material in the
Z-direction, such as perpendicular to the support plane. Similar to
above, it can be calculated that the (periodic) pattern of printed
(or deposited) material has a period which is equal to the
translation speed divided by the frequency of the vibrating motion
(in case the printed material does not experience a vibrating
motion there will be no periodic pattern and hence no period). In
general the pattern period will be larger than zero, but a
practical upper limit of the pattern period may be 200% of the
height of the printed material (which is the height without the
vibrating motion), because otherwise e.g. part of the printed
material may float and is thus not deposited on an previous layer
or on the support structure. Combining this results in that the
height multiplied with the vibration frequency divided by the
translation speed should be smaller than 0.5. A vibrating motion
along the Z-direction can also result in a periodic pattern in the
XY-plane with an amplitude depending on, amongst others, the
amplitude of the vibrating motion with respect to the height of the
printed layer.
[0021] In an embodiment the pattern period of the printed material
induced by the vibrating motion is smaller than 1000 times the
width of the printed material. This results in that the width
multiplied with the vibration frequency divided by the translation
speed is larger than 0.001. A period above this practical upper
limit of 1000 times the width of the printed material corresponds
to relatively large features that can also be realized with
sufficient accuracy by the translating motion itself and for which
no separate vibrating motion with a frequency larger than in the
order of 10 Hz is required (see also below). For example, a
printing speed of 1000 mm/sec and a width of the printed material
of 0.3 mm results in a maximum frequency of the vibrating motion of
30 Hz to achieve a pattern period of 30 cm which is at minimum 1000
times the width of the printed material.
[0022] In an embodiment of the 3D printing device according to the
invention, the vibrating motion has a vibration frequency larger
than 10 Hz. For lower values of the frequency of the vibrating
motion, the period patterns can also be created by the relative
translation of the printer nozzle with respect to the support
structure, and at frequencies above around 10 Hz the additional
vibrating motion will greatly improve the accuracy of the printed
periodic pattern.
[0023] In an embodiment of the 3D printing device according to the
invention, the vibration actuator is arranged to provide a first
vibrating motion of the first part of the support structure and a
second vibrating motion of a second part of the support structure,
the second vibrating motion being different from the first
vibrating motion with respect to vibration frequency and/or
vibration amplitude. This provides for creating a 3D object with
features sizes (created by the vibrating motion) that depend on the
location on the support structure. For example, at the first part
of the support structure, corresponding to a first part of the
printable 3D object, the vibrating motion provides features sizes
in the order of 0.1 mm, and at the second part of the support
structure, corresponding to a second part of the printable 3D
object, the vibrating motion provides feature sizes in the order of
0.05 mm. Optionally, another part (than the first and second part)
of the support structure does not vibrate at all.
[0024] In an embodiment of the 3D printing device according to the
invention, at least a third part of the support structure is
clamped to influence the vibrating motion of the third part of the
support structure. In this way the third part of the support
structure, corresponding to a third part of the 3D printable
object, will for example not vibrate, or will experience a
negligible amplitude, such that at the third part of the 3D
printable object a shape is created with a basic pattern created
only by the relative translation of the support structure with
respect to the printer nozzle. The clamping provides for a
reduction or restriction of the vibrating motion at the third part
of the support structure. In practice the vibration, such as the
vibration amplitude, in a direction perpendicular to the support
structure plane will be influenced the most by this clamping (i.e.
the vibration in the Z-direction).
[0025] In an embodiment of the 3D printing device according to the
invention, the vibration actuator is arranged to provide the
support structure with a vibration pattern with a frequency and
amplitude that varies over the support structure according to a
vibration pattern. In this way the vibration frequency and the
vibration amplitude depend on the location on the support
structure, and thus the 3D object will have a pattern with periodic
features that depend on the position of the printable 3D object on
the support structure corresponding to the vibration pattern. For
example, the vibration actuator may comprise a plurality of
vibration sources each acting on a different part of the support
structure thereby providing a predetermined vibrating motion at the
different parts of the support structure. Especially the vibration,
such as the vibration amplitude, in a direction perpendicular to
the support structure will be influenced the most by this
embodiment (i.e. the vibration in the Z-direction).
[0026] In an embodiment of the 3D printing device according to the
invention, the vibration actuator is an ultrasound actuator. The
ultrasound actuator can advantageously provide for a vibration
pattern depending on the properties of the support structure, such
as mass, size, etc. that determine resonance frequencies of the
support structure.
[0027] In an embodiment of the 3D printing device according to the
invention, the 3D printer further comprises a processor arranged to
control the vibrating motion of the support structure and the
relative translation of the printer nozzle with respect to the
support structure. In this way the translating and vibrating
motions can be aligned to each other. Advantageously the processor
comprises instructions for different time periods with regard to
the translation speed and direction, pausing periods (e.g. at the
end of a printed layer), the vibration frequency and the vibration
amplitude and direction.
[0028] In an embodiment of the 3D printing device according to the
invention, the support structure comprises a vibration plate, the
vibration actuator being arranged to provide a vibrating motion to
the vibration plate. In general this results in that the vibration
actuator has to provide the vibrating motion to a smaller (less
mass) structure, which is more energy efficient and may provide for
a faster and more accurate vibrating motion.
[0029] In a second aspect the invention provides a method for
manufacturing a 3D object, especially a fused deposition modeling
method for manufacturing a 3D object, wherein the method comprises
the steps of: depositing a material from a printer nozzle on a
support structure while translating the support structure and the
printer nozzle relative to each other with a translation speed in a
translation direction, and vibrating at least a first part of the
support structure relative to the printer nozzle in a direction
different from the translation direction.
[0030] Advantages and variations of the first aspect of the
invention similarly apply to this second aspect of the invention,
and vice versa.
[0031] In an embodiment of the method according to the invention,
the frequency and/or amplitude and/or the direction of the
vibrating motion varies as a function of time. This provides for an
additional degree of freedom in creating a specific shape or
pattern of the 3D object.
[0032] In an embodiment of the method according to the invention,
the vibrating motion between subsequent disposed material layers is
in phase. The vibrating motion being in phase between subsequent
layers means that the amplitude and frequency of subsequently
deposited layers (on top of each other) are similar such that a
minimum/maximum of the periodic pattern of a first layer coincides
with a minimum/maximum of the periodic pattern of a second
subsequent layer deposited, or printed, on the first layer. In this
way a fixation or adhesion between these subsequent disposed
material layers is maximized. By creating a difference in phase,
e.g. a difference in frequency, between subsequent disposed
material layers the adhesion or fixation between these subsequent
disposed material layers can be tuned.
[0033] In an embodiment of the method according to the invention,
the method further includes a time delay before depositing a second
(subsequent) material layer on top of a first material layer. This
provides for example for an optimum alignment between subsequent
layers.
[0034] In a third aspect the invention provides a computer-readable
storage medium instructions that when executed by at least one
processor of a 3D printing device causes the printing device to
generate a 3D object, or a computer-readable 3D model for use in 3D
manufacturing, comprising instructions for depositing a material
from a printer nozzle on a support structure, instructions for
generating a translating motion of the support structure relative
to the printer nozzle with a translation speed in a translation
direction, and instructions for generating a vibrating motion of a
part of the support structure relative to the printer nozzle in a
direction different from the translation direction.
[0035] Advantages and variations of the first aspect of the
invention similarly apply to this third aspect of the invention,
and vice versa.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] Embodiments of the invention will now be described, by way
of example only, with reference to the accompanying schematic
drawings in which corresponding reference symbols indicate
corresponding parts, and in which:
[0037] FIG. 1 schematically depicts an embodiment of a 3D printing
device according to the invention;
[0038] FIGS. 2A-2B schematically depict periodic patterns created
with the 3D printing device according to the invention;
[0039] FIG. 3 schematically depicts a periodic pattern created with
the 3D printing device according to the invention;
[0040] FIG. 4 schematically depicts a periodic pattern created with
the 3D printing device according to the invention; and
[0041] FIG. 5A-5C schematically depict periodic patterns created
with the 3D printing device according to the invention.
[0042] The drawings are not necessarily on scale.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0043] FIG. 1 schematically depicts an embodiment of a 3D printing
device, or 3D printer, according to the invention which may for
example be used for the advanced manufacturing (AM) method as
described herein. A 3D printing device 500 comprises a printer head
501 having a printer nozzle 502 for printing, or depositing, a 3D
printable material onto a support structure 550. By way of example,
an embodiment of an FDM printer is schematically depicted.
[0044] Reference 530 indicates the functional unit configured to
print a 3D object, especially FDM 3D printing. This reference may
also indicate the 3D printing stage unit. Here, only the printer
head 501 for providing 3D printed material, such as a FDM 3D
printer head is schematically depicted. The 3D printer of the
present invention may include a plurality of printer heads, though
other embodiments are also possible. Reference 320 indicates a
filament of printable 3D printable material (such as indicated
above). For the sake of clarity, not all features of the 3D printer
have been depicted, only those that are of special relevance for
the present invention. The 3D printer 500 is configured to generate
a 3D object 10 by depositing, or depositing, a plurality of
filaments 320 on the support structure 550 wherein each filament
320 comprises 3D printable material, such as having a melting point
T.sub.m. In this example, the 3D printer 500 is configured to heat
the filament material upstream of the printer nozzle 502. This may
e.g. be done with a device comprising one or more of an extrusion
and/or heating function. Such a device is indicated with reference
573, and is arranged upstream from the printer nozzle 502 (i.e. in
time before the filament material leaves the printer nozzle 502).
Reference 572 indicates a spool with material, especially in the
form of a wire. The 3D printer 500 transforms this in a filament or
fiber 320. By arranging filament by filament and filament on
filament, the 3D object 10 may be formed. The 3D printing technique
used herein is however not limited to FDM (see also above).
Reference 580 indicates a storage of the printable material (or a
precursor thereof). For example, the spool with material may be
used as storage.
[0045] The 3D printer 500 further comprises a conversion unit 1100,
here by way of example a heater unit 1150. The heater unit 1150 may
be functionally coupled to the printer head 501. The heater unit
1150 is especially configured to provide heat to the printable
material on the flow (to the support structure 550). Optionally,
the heater unit may be comprise a laser.
[0046] Arrows 50 and 55 represent the vibrating motion of the
support structure 550 respectively parallel to the plane of the
support structure 550 (which is also the main translation direction
of the support structure 550 and/or the printer nozzle 502) and
perpendicular to the support structure 550. The vibrating motion
50, 55 is provided for by a vibration actuator (not shown), such as
for example a vibration motor (e.g. linear resonant actuator
vibration motor, eccentric rotating mass vibration motor), or a
(ultra)sound actuator such as a loudspeaker with an electronic
signal generator for acoustic excitation. A controller (not shown)
may be arranged to control the (relative) movements, translations
and vibrations, of the printer nozzle (printer head) and the
support structure. For example, the controller may switch off the
vibrating motion for a predetermined amount of time, at a specific
position, for a specific layer, etc. In this way a location
dependent periodic pattern is printed wherein the amplitude and/or
frequency etc. vary over the printed 3D object.
[0047] The direction of the vibrating motion 50, i.e. the vibrating
motion parallel to the plane of the support structure 550 is
generally not in the same direction as the direction of the
printing, i.e. the direction of the relative movement, or
translation, of the printer nozzle with respect to the support
structure. Thus, the vibration, which is a (linear) periodic
movement, has an angle different from zero with the (linear)
translation. In this way a pattern can be created with (periodic)
features depending on the frequency and amplitude of the vibrating
motion and depending on the angle between the direction of the
vibrating motion and the printing, or translation, direction.
[0048] In an embodiment the support structure 550 vibrates at a
specific vibration frequency and with a specific vibration
amplitude. As a function of time, thus while the material is
deposited on the support structure 550, the vibration frequency
and/or the amplitude may vary or may be constant. Optionally, the
vibrating motion may be absent during a period of time of the
printing process.
[0049] In another embodiment only a first part of the support
structure 550 vibrates. For example, the vibration actuator only
actuates or excites, and hence provides a vibrating motion to, the
first part of the support structure 550. In a further example, a
third part of the support structure 550 is clamped in such a way
that it does not vibrate or vibrates to a lesser extent (i.e. a
smaller amplitude), for example by using a fixation, or applying a
local weight thereby mainly locally suppressing the vibrating
motion 55 in the Z-direction, i.e. in a direction perpendicular to
the plane defined by the support structure 550 and/or the vibrating
motion parallel to the plane of the support structure 550 (XY
plane). In another example, the vibration actuator is arranged to
provide a vibration pattern onto the support structure in which the
vibration frequency and/or vibration amplitude vary as a function
of the position on the support structure. This can be implemented,
for example, by an (ultra)sound actuator leading to acoustic
resonance of the support structure 550. In this way the vibrations
can be localized wherein a first part of the support structure
vibrates and another part of the support structure does not vibrate
or vibrates to a less extent, for example with a smaller amplitude.
Alternatively, multiple sources for vibration can act on the
support structure at different positions to generate relatively
complex vibration patterns.
[0050] In an embodiment the support structure comprises a base
plate on which a vibration plate is provided and the printable
material is deposited on the vibration plate (not shown). The base
plate provides for the relative translation and the vibration plate
provides for the vibrating motion 50, 55. In this way the energy
required to keep the printed object at a certain distance to the
printer nozzle and the energy needed for the vibrating motion can
be separated and separate actuators can be employed optimized for
their specific functions. The vibration plate advantageously is
thinner (less mass) than the base plate and thus the energy
required for the vibrations is reduced which may result in a more
accurate vibrating motion.
[0051] The vibrating motion can be varied when depositing a layer,
but it can also be varied between subsequent deposited layers, i.e.
the vibrating motion while printing a first layer is different
while printing the next, subsequent layer on the first layer, for
example by setting a different amplitude and/or frequency. The
fixation between subsequent layers can be tuned by applying and
selecting a specific vibrating motion depending on several
characteristics of the printed material itself, e.g. dimensions and
material properties etc., the frequency and amplitude of the
vibrating motion, the translation speed and other process
parameters, such as for example temperature. For example, a first
layer is deposited with a first vibration frequency and a first
vibration amplitude, and a subsequent layer is deposited with a
second vibration frequency and a second vibration amplitude. A
vibrating motion perpendicular to support structure (i.e. in the
Z-direction) especially may result in an improved adhesion or
fixation between subsequently printed layers because at some
locations the printer head is closer to the previously deposited
layer and hence will press the printable (to be deposited) material
onto the (previously) printed layer.
[0052] The pattern shape of the printed material will have a
pattern period and pattern amplitude (defined as pattern extension
perpendicular to the translation direction) as a result of the
vibrating motion which period and amplitude are superposed to the
basic pattern of the printed material which is provided for by the
relative translating motion between the printer nozzle and the
support structure and which basic pattern will have a pattern
width, defined by the shortest distance of the printed material as
measured parallel to the plane of the support structure (and
perpendicular to the translation direction), and a pattern height
which is defined by the shortest distance of the printed material
as measured perpendicular to the plane of the support structure
(Z-direction).
[0053] The vibrating motion in the different embodiments is
characterized by a vibration period 1/f, wherein f is the frequency
of the vibrating motion, and a vibration amplitude A (unit:
meters). FIG. 2A shows a schematic view of a periodic pattern 110
created with the 3D printing device according to the invention of
deposited, or printed, material created by a translating motion 52
in the X-direction having a translation, or printing, speed v
superposed with a vibrating motion 50 in the Y-direction or in the
Z-direction. The printer nozzle prints a continuous line by moving
(translating) the support structure 550 with respect to the printer
nozzle 502 with the translation speed v. The vibrating motion 50 of
the support structure induces periodic movements at the location of
the printable material, i.e. where the printable material is
dispensed or deposited, which results in a pattern with a shape, or
form, which is additionally (next to the relative translating
motion 52) determined by the vibration frequency and amplitude. The
periodic pattern 110 has a period PP which is equal to the
translation, or printing, speed v divided by the frequency f of the
vibrating motion 50: PP=v/f. The periodic pattern 110 further has a
pattern amplitude PA which is, in this case, equal to the amplitude
A of the vibrating motion 50 because the direction of the vibrating
motion (in the Y-direction or in the Z-direction) is perpendicular
to the direction of the translation. FIG. 2B shows a periodic
pattern 120 similar to that shown in FIG. 2A, except that the
printed material has a larger width than the periodic pattern 110
shown in FIG. 2A.
[0054] FIG. 3 shows a schematic example of a periodic pattern 130
created with the 3D printing device according to the invention. In
this embodiment the direction of a translating motion 62, having a
translation speed v, and the direction of a vibrating motion 60 are
both in the X-Y plane and have an angle .alpha. (different from
zero) with respect to each other. The periodic pattern 130 has a
period PP2 which is equal to the translation speed v divided by the
multiplication of the frequency f of the vibrating motion 60 and
the absolute value of the sinus of the angle .alpha.:
PP2=v/(f*abs(sin(.alpha.))). The periodic pattern 130 further has a
pattern amplitude PA2 which is, in this case, equal to the
amplitude A2 of the vibrating motion 60 multiplied by the absolute
value of the sinus of the angle .alpha.: PA2=abs(sin
(.alpha.))*A2.
[0055] In an embodiment the width multiplied by the vibration
frequency divided by the translation speed is larger than 0.5. It
can be calculated that the pattern of printed (or deposited)
material has a period which is equal to the translation speed
divided by the frequency of the vibrating motion (in case the
printed material does not experience a vibrating motion there will
be no periodic pattern and hence no period). In general the pattern
period will be larger than zero, but a practical lower limit of the
pattern period may be 200% of the width of the printed material
(which is the width without the vibrating motion), because
otherwise e.g. part of the material from the back and forth
movement during the vibrating motion would be deposited in the same
location which may result in for example unwanted thickness/height
variations and thereby overlap of printed material during the
vibrating motion is avoided in this way and unwanted pattern
variations, such as interference patterns, are avoided. Combining
this results in that the width multiplied with the vibration
frequency divided by the translation speed should be larger than
0.5. For example, a printing speed of 100 mm/sec and a width of the
printed material of 0.3 mm results in a maximum frequency of the
vibrating motion of 167 Hz to achieve a pattern period of 0.6 mm
which is at minimum 200% of the width of the printed material (i.e.
twice the width).
[0056] In an embodiment the pattern period of the printed material
induced by the vibrating motion is smaller than 1000 times the
width of the printed material. This results in that the width
multiplied with the vibration frequency divided by the translation
speed is larger than 0.001. A width above this practical upper
limit of 1000 times the width of the printed material corresponds
to relatively large features that can also be realized with
sufficient accuracy by the translating motion itself and for which
no separate vibrating motion with a frequency larger than in the
order of 10 Hz is required (see also below). For example, a
printing speed of 1000 mm/sec and a width of the printed material
of 0.3 mm results in a maximum frequency of the vibrating motion of
30 Hz to achieve a pattern period of 30 cm which is at minimum 1000
times the width of the printed material.
[0057] In case of a vibrating motion in a direction perpendicular
to a plane defined by the support structure, i.e. in the
Z-direction perpendicular to the X-Y plane in which the translating
motion is provided, a pattern is provided in which the extension
(or height) of the printed material perpendicular to the plane of
support structure will exhibit a periodic structure determined at
least by the frequency f and amplitude A of the vibrating motion
and the translation speed v. FIG. 4 shows a schematic 3D view of
such a vibrating motion in the Z-direction resulting in subsequent
layers having a periodic pattern in the Z-direction. In practice
the amplitude of the vibrating motion should not exceed 200% of the
height of the printed material in order to avoid for the nozzle to
get in direct contact with the underlying layer. In case there is
no layer at the location where the printable material will be
deposited this limit may even be lower than 200% of the height of
the printed material. Furthermore, preferably subsequently printed
layers should exhibit a periodic pattern that is in phase (i.e.
having a similar periodic pattern) to avoid pressing the printer
nozzle into the previously printed layer. Typically the thickness
or height of a printed layer is 0.02 mm to 2 mm. The vibrating
motion can cause the height to vary between 0.01 mm and 4 mm.
[0058] The (additional) vibrating motion of the support structure
may be used to improve the adherence properties between adjacent
material layers. If the vibrating motion during the deposition of
adjacent layers is in phase, the shape of the printed material will
be conformal, hence realizing a closely packed print, as is
schematically shown in FIG. 5A for five subsequent layers 511, 512,
513, 514, 515. By changing the phase and/or amplitude of the
vibrating motion, the amount of overlap and the size of gaps
between adjacent material patterns can be tuned, as is
schematically shown in FIGS. 5B and FIG. 5C. FIG. 5B shows
schematically that subsequent or adjacent layers 521, 522 are
printed, or deposited with a different amplitude of the vibrating
motion, for example layer 521 has a smaller amplitude than
adjacent, or subsequent, layer 522. In this way the adherence
between adjacently deposited, or dispensed, material can be tuned.
Optionally, by including gaps or voids between adjacent lines,
which can be provided by having subsequently printed layers with
periodic patterns that are out of phase with respect to each other,
optical properties of the 3D object can be tuned as well,
especially when transparent or translucent materials are used in
the printing process. Variations of the surface as well as the
adherence, or mechanical connection, between adjacently printed
materials may be induced, and/or voids can be formed that will
induce scattering or even a sparkling effect. In this way (local)
optical effects can be achieved. FIG. 5C shows schematically that
subsequently or adjacent printed layers 531, 532 have a different
phase, i.e. the peaks (maxima) and valleys (minima) of the adjacent
layers 531, 532 do not coincide.
[0059] The vibration frequency is in general larger than or equal
to 10 Hz. For lower values of the frequency of the vibrating
motion, periodic patterns can also be created by the relative
translation of the printer nozzle with respect to the support
structure, and at frequencies above 10 Hz the additional vibrating
motion will greatly improve the accuracy of the printed periodic
pattern.
[0060] Optionally, a delay time is included when switching to
printing of the next (subsequent) layer in order to start a new
layer in phase with the previous layer. This device time can also
be used to achieve a specific pattern in the 3D object in the
direction perpendicular to the support structure plane, such as a
spiraling or zigzag pattern. Specific resonances, such as
resonances according to a Chladni pattern, may provide for a
localization of the vibrating motion and hence an improved
resolution of the resulting periodic pattern.
[0061] The term "substantially" herein, such as in "substantially
consists", will be understood by the person skilled in the art. The
term "substantially" may also include embodiments with "entirely",
"completely", "all", etc. Hence, in embodiments the adjective
substantially may also be removed. Where applicable, the term
"substantially" may also relate to 90% or higher, such as 95% or
higher, especially 99% or higher, even more especially 99.5% or
higher, including 100%. The term "comprise" includes also
embodiments wherein the term "comprises" means "consists of". The
term "and/or" especially relates to one or more of the items
mentioned before and after "and/or". For instance, a phrase "item 1
and/or item 2" and similar phrases may relate to one or more of
item 1 and item 2. The term "comprising" may in an embodiment refer
to "consisting of" but may in another embodiment also refer to
"containing at least the defined species and optionally one or more
other species".
[0062] Furthermore, the terms first, second, third and the like in
the description and in the claims, are used for distinguishing
between similar elements and not necessarily for describing a
sequential or chronological order. It is to be understood that the
terms so used are interchangeable under appropriate circumstances
and that the embodiments of the invention described herein are
capable of operation in other sequences than described or
illustrated herein.
[0063] The devices herein are amongst others described during
operation. As will be clear to the person skilled in the art, the
invention is not limited to methods of operation or devices in
operation.
[0064] It should be noted that the above-mentioned embodiments
illustrate rather than limit the invention, and that those skilled
in the art will be able to design many alternative embodiments
without departing from the scope of the appended claims. In the
claims, any reference signs placed between parentheses shall not be
construed as limiting the claim. Use of the verb "to comprise" and
its conjugations does not exclude the presence of elements or steps
other than those stated in a claim. The article "a" or "an"
preceding an element does not exclude the presence of a plurality
of such elements. The invention may be implemented by means of
hardware comprising several distinct elements, and by means of a
suitably programmed computer. In the device claim enumerating
several means several of these means may be embodied by one and the
same item of hardware. The mere fact that certain measures are
recited in mutually different dependent claims does not indicate
that a combination of these measures cannot be used to
advantage.
[0065] The invention further applies to a device comprising one or
more of the characterizing features described in the description
and/or shown in the attached drawings. The invention further
pertains to a method or process comprising one or more of the
characterizing features described in the description and/or shown
in the attached drawings.
[0066] The various aspects discussed in this patent can be combined
in order to provide additional advantages. Furthermore, some of the
features can form the basis for one or more divisional
applications.
* * * * *