U.S. patent application number 15/184085 was filed with the patent office on 2017-12-21 for ultrasonic welding of dissimilar sheet materials.
The applicant listed for this patent is GM Global Technology Operations LLC. Invention is credited to Jorge F. Arinez, Mihaela Banu, Shixin Hu, Yongqiang Li, Daniel Shriver, Kaifeng Wang.
Application Number | 20170361540 15/184085 |
Document ID | / |
Family ID | 60481509 |
Filed Date | 2017-12-21 |
United States Patent
Application |
20170361540 |
Kind Code |
A1 |
Li; Yongqiang ; et
al. |
December 21, 2017 |
ULTRASONIC WELDING OF DISSIMILAR SHEET MATERIALS
Abstract
A ultrasonic welding method of joining dissimilar-material
workpieces, such as sheet materials, and the joined components
formed thereby. The method includes applying ultrasonic energy to a
thermoplastic piece to fill a hole of a dissimilar piece to form a
weld point that is made up with polymer from the thermoplastic
piece. In general, the geometry of the thermoplastic piece is not
altered during the process. The dissimilar piece generally has a
higher melting temperate and can be metal, thermoset polymers, or
other thermoplastic material. The welded pieces can be arranged in
a lap, laminate, or double lap configuration. In some embodiments,
the hole of the dissimilar sheet material includes undercut
features that improve the mechanical interlock between the
dissimilar pieces. In some embodiments, the weld point has a
mushroom cap to improve mechanical interlock.
Inventors: |
Li; Yongqiang; (Sunnyvale,
CA) ; Hu; Shixin; (Ann Arbor, MI) ; Shriver;
Daniel; (Ann Arbor, MI) ; Wang; Kaifeng; (Ann
Arbor, MI) ; Banu; Mihaela; (Ann Arbor, MI) ;
Arinez; Jorge F.; (Rochester Hills, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GM Global Technology Operations LLC |
Detroit |
MI |
US |
|
|
Family ID: |
60481509 |
Appl. No.: |
15/184085 |
Filed: |
June 16, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B29C 66/71 20130101;
B29C 66/71 20130101; B29C 66/7212 20130101; B29K 2277/10 20130101;
B29C 65/8215 20130101; B29C 66/71 20130101; B29C 66/71 20130101;
B29C 66/8322 20130101; B29C 65/608 20130101; B29C 66/1122 20130101;
B29C 66/71 20130101; B29C 66/7392 20130101; B29C 66/7212 20130101;
B29C 66/7212 20130101; B29K 2079/085 20130101; B29K 2079/08
20130101; B29C 65/08 20130101; B29C 65/606 20130101; B29C 66/73755
20130101; B29C 66/02241 20130101; B29K 2101/12 20130101; B29C
66/7422 20130101; B29C 65/562 20130101; B23K 2103/18 20180801; B23K
20/22 20130101; B29C 65/4895 20130101; B29C 66/71 20130101; B29K
2021/00 20130101; B29K 2023/06 20130101; B29K 2061/04 20130101;
B29K 2309/08 20130101; B29K 2081/04 20130101; B29K 2077/00
20130101; B29K 2023/12 20130101; B29K 2277/10 20130101; B29K
2067/046 20130101; B29K 2049/00 20130101; B29K 2069/00 20130101;
B29K 2055/02 20130101; B29K 2081/06 20130101; B29K 2071/12
20130101; B29K 2027/06 20130101; B29K 2027/18 20130101; B29K
2067/00 20130101; B29K 2025/06 20130101; B29K 2063/00 20130101;
B29K 2071/00 20130101; B29K 2307/04 20130101; B29K 2075/00
20130101; B29C 65/02 20130101; B29C 66/43 20130101; B29C 66/71
20130101; B29C 66/71 20130101; B29C 66/9513 20130101; B29K 2023/12
20130101; B29K 2071/00 20130101; B29C 66/81423 20130101; B23K
2103/42 20180801; B23K 2103/10 20180801; B29C 66/304 20130101; B29C
66/712 20130101; B29C 66/7212 20130101; B29C 66/949 20130101; B29C
66/71 20130101; B23K 20/10 20130101; B29C 65/72 20130101; B29C
66/21 20130101; B29C 66/71 20130101; B29C 66/73116 20130101; B29C
66/73921 20130101; B29C 66/74283 20130101; B29C 65/561 20130101;
B29C 66/71 20130101; B29C 66/71 20130101; B29C 66/81425 20130101;
B29C 66/71 20130101; B29C 66/939 20130101; B29C 66/71 20130101;
B29C 66/30325 20130101; B29C 66/71 20130101; B29C 66/71 20130101;
B29C 66/71 20130101; B29C 66/742 20130101; B29C 66/929 20130101;
B29C 66/72143 20130101; B23K 2103/05 20180801; B29C 66/3032
20130101; B29C 66/71 20130101; B29C 66/71 20130101; B29K 2067/046
20130101; B29C 65/607 20130101; B29C 66/71 20130101; B29C 65/48
20130101; B29C 65/64 20130101; B29C 66/71 20130101; B29K 2079/08
20130101; B29K 2081/04 20130101; B29C 66/7394 20130101; B29C
66/9517 20130101; B29K 2705/00 20130101; B29C 66/71 20130101; B29C
66/81431 20130101 |
International
Class: |
B29C 65/60 20060101
B29C065/60; B23K 20/10 20060101 B23K020/10; B29C 65/00 20060101
B29C065/00; B29C 65/08 20060101 B29C065/08 |
Claims
1. A welded component, formed by ultrasonic welding together
dissimilar-material pieces, comprising: a thermoplastic piece; and
a higher melting temperate (HMT) piece having at least one hole and
being joined to the thermoplastic piece by a weld point comprising
material from the thermoplastic piece filing the hole; wherein the
hole has at least one undercut feature filled with the material
from the thermoplastic piece to create part of the weld point.
2. The welded component of claim 1, wherein the at least one hole
is a through hole or a blind hole, and the at least one undercut
feature includes a step, an internal thread, or a combination
thereof.
3. The welded component of claim 1, wherein the thermoplastic piece
and the HMT piece are joined to form a lap joint or a laminate
joint.
4. The welded component of claim 1, wherein said hole is one of a
plurality of holes of the HMT, each being filled with the material
from the thermoplastic piece to form a plurality of weld
points.
5. The welded component of claim 4, wherein: the weld point
includes a convex lower head of material of the thermoplastic piece
connecting the material of the thermoplastic piece filling each of
the plurality of holes; and the convex lower head overlaps a
portion of a lower surface of the HMT piece.
6. The welded component of claim 1, wherein: the thermoplastic
piece is a first thermoplastic piece; the welded component further
comprises a second thermoplastic piece; the first and second
thermoplastic pieces sandwich the HMT piece, forming a double lap
joint; said hole is one of a first set of holes of the HMT piece,
the first set of hole being filed with the material of the first
thermoplastic piece to form a first set of weld points; and the HMT
piece comprises a second set of holes being filled with material of
the second thermoplastic piece and/or the material of the first
thermoplastic piece, to form a second set of weld points.
7. The welded component of claim 1, wherein: the thermoplastic
piece is a first thermoplastic piece; the welded component further
comprises a second thermoplastic piece sandwiching the HMT piece
with the first thermoplastic piece to form a double lap joint; and
the at least one hole of the HMT piece is filled with thermoplastic
from the first and the second thermoplastic pieces.
8. The welded component of claim 1, wherein: the HMT piece is a
first HMT piece; the welded component further comprises a second
HMT piece abutting the first HMT piece; the two HMT pieces are
joined together by the thermoplastic piece to form a butt joint;
the at least one hole of the first HMT piece is a first set of
holes; the second HMT piece comprises a second set of holes; and
all holes are filled with thermoplastic from the thermoplastic
piece.
9. The welded component of claim 1, wherein: the HMT piece is a
first HMT piece; the welded component further comprises a second
HMT piece stacked with the first HMT piece; the two HMT pieces are
joined together with the thermoplastic piece; the at least one hole
of the first HMT is a first set of holes; the second HMT piece
comprises a second set of holes aligned with the first set of holes
of the first HMT piece in the stack; and all holes are filled with
thermoplastic from the thermoplastic piece.
10. A method, of forming a welded component of dissimilar-material
pieces by ultrasonic welding, comprising, placing a thermoplastic
piece atop a higher melting temperate (HMT) piece, wherein the HMT
piece comprises at least one hole, to cover the hole in the HMT
piece; and applying ultrasonic energy to the thermoplastic piece
above the hole of the HMT piece using an ultrasonic horn to melt
material of the thermoplastic piece so that material melted fills
the hole of the HMT piece to create a weld point joining the
thermoplastic piece and the HMT piece to form the welded
component.
11. The method of claim 10, wherein the at least one hole has at
least one undercut feature and some of the material melted fills
the undercut feature.
12. The method of claim 11, wherein the at least one undercut
feature comprises a step, internal threads, or a combination
thereof.
13. The method of claim 10, wherein: said hole is one of a
plurality of holes of the HMT piece; and the placing and the
applying are performed to fill each hole with the material of the
thermoplastic piece melted.
14. The method of claim 10, further comprising, prior to applying
ultrasonic energy, placing the HMT piece on an anvil having a
generally flat top surface, wherein a bottom of the weld point
being formed is kept flat by the generally flat top surface of the
anvil as the melted thermoplastic material fills the hole.
15. The method of claim 10, further comprising: placing the HMT
piece on an anvil prior to applying ultrasonic energy; wherein: the
anvil has a top surface and a concavity in the top surface; the
concavity is wider than the hole of the HMT piece, forming an
under-piece feature when the HMT piece is placed on the anvil; and
when the material of the thermoplastic piece is melted by the
ultrasonic energy, the melted material fills the hole and the
concavity of the anvil, including beneath the under-piece feature,
forming a convex bottom portion of the weld point overlapping a
bottom surface of the HMT piece.
16. The method of claim 10, wherein: the thermoplastic piece is a
first thermoplastic piece; the at least one hole of the HMT piece
is a first set of holes, each having an opening at a top surface of
the HMT piece; the first thermoplastic piece is placed adjacent the
top surface of the HMT piece; the HMT piece further comprises a
second set of holes, each having an opening at a bottom surface of
the HMT piece; and the method further comprises: placing a second
thermoplastic piece adjacent the bottom surface of the HMT piece,
covering the second set of holes in the HMT piece, sandwiching the
HMT piece with the first thermoplastic piece; and applying
ultrasonic energy to the second thermoplastic piece above the
second set of holes of the HMT piece, so that material of the
second thermoplastic piece melts and flows into the second set of
holes.
17. The method of claim 10, wherein the method is performed to form
a double lap joint to join the thermoplastic and HMT pieces of the
welded component, wherein: the ultrasonic horn is a first
ultrasonic horn; and applying the ultrasonic energy to the second
thermoplastic piece is performed using a second ultrasonic horn
having a larger diameter than the first ultrasonic horn.
18. The method of claim 10, wherein: the HMT piece is a first HMT
piece; the at least one hole of the first HMT piece is a first set
of holes; and the method further comprising butting the first HMT
piece with a second HMT piece having a second set of holes before
placing the thermoplastic piece on top of the holes of the first
and second HMT pieces and applying the ultrasonic energy to fill
all of the holes of the first and second sets with the material
from the thermoplastic piece to form the butt joint joining the
first and second HMT pieces to the thermoplastic piece.
19. The method of claim 10, wherein: the HMT piece is a first HMT
piece; and the at least one hole of the first HMT piece is the
first set of holes and the method further comprises stacking a
second HMT piece comprising a second set of holes with the first
HMT piece and aligning the first set of holes with the second set
of holes before applying ultrasonic energy to the thermoplastic
piece above the holes of the first and second HMT pieces to fill
all of the holes with material melted from the thermoplastic piece
to join the first and second HMT pieces to the thermoplastic
piece.
20. A method, for joining dissimilar-material workpieces,
comprising: positioning a higher melting temperature (HMT) piece
adjacent an anvil-cutting apparatus; moving a cutter of the
apparatus into a hole of the HMT piece; extending a cutting insert
of the cutter and rotating the cutting insert to form a void in a
side wall of the hole; retracting the cutting insert; retracting
the cutter from the hole; positioning a thermoplastic piece atop
the HMT piece; and applying ultrasonic energy to the thermoplastic
piece causing material of the thermoplastic piece to melt and move
into the hole until the material melted contacts a top of the
cutter of the anvil-cutter arrangement, thereby filling the hole
and the void formed.
21. The method of claim 20, wherein: the anvil-cutter arrangement
has a slot in which the cutter is slidably positioned; the slot is
wider than the hole of the HMT piece; retracting the cutter
includes retracting the cutter into a body of the cutter-anvil
arrangement so that a top surface of the cutter is lower than an
adjacent top surface of the body, so that a lower surface of the
HMT piece exposed can act as an under-piece feature for receiving
material melted from the thermoplastic piece; and by application of
the ultrasonic energy, the melted material fills a space between
sides of the slot, atop the top surface of the cutter, and beneath
the under-piece feature formed by the exposed surface of the HMT
piece.
Description
TECHNICAL FIELD
[0001] The present disclosure relates generally to ultrasonic
welding and, more particularly, to a welded piece created by
joining dissimilar sheet materials and the process of creating the
welded piece.
BACKGROUND
[0002] Welding is a common way to join similar and dissimilar
materials in a wide range of industries, including consumer
electronics, home products and appliances, farming, construction
equipment, transportation systems, and the like.
[0003] The dissimilar materials can include dissimilar metals,
dissimilar polymers, or combinations of polymers and metals. The
manufacturer can select favorable characteristics, such as being
lightweight, highly-conformable or shapeable, strong, durable, or
having a desired texture or color by combining some polymer or
composite materials with other materials. An article of manufacture
may include various components (exterior, interior, or decorative
features) where materials are selected and configured to withstand
a hot and/or chemically aggressive environment or for painting or
chemical resistance over time.
[0004] With the increased use of polymers and other low-mass
materials, compression molding and post-mold joining techniques,
such as laser welding and ultrasonic welding, are also being used
more commonly. Some workpieces, including polymer composites, have
relatively low melting points, and some workpieces, including
metals, have relatively high conductivity. Whether welding one or
both types of workpiece, it is difficult and in many cases
impossible to join the workpieces at a target interface accurately,
quickly, and with minimal melting of other portions of the
workpieces.
[0005] Traditional ultrasonic welding techniques such as heat
staking have various shortcomings. With reference to the figures,
and more particularly the first figure, FIG. 1 shows a heat staking
process joining a thermoplastic piece 110 with a metal piece 210 to
form a lap joint. The thermoplastic piece 110 comprises a boss 112
operably connected to the body of the thermoplastic piece. The boss
and body combination of the thermoplastic piece 110 are obtained
for example by molding, such as injection molding. The metal piece
210 comprises a through hole 212, which can be obtained through
drilling a hole into the metal piece. Next, the metal piece 210 is
assembled 310 with the thermoplastic piece 110 by aligning and then
fitting the boss 112 and the through hole 212 prior to heat
staking. The stacked piece 10 is then subject to a heat staking
process 312 using a concave anvil 410 to form a mushroom cap 114
from the boss 112. The mushroom cap 114 generally has a diameter
that is larger than the diameter of the hole 212 such that the
interaction of the mushroom cap 114 and the hole 212 provides
mechanical interlock to hold the two pieces 110, 210 together to
form a welded piece 20.
[0006] The hole 212 of the metal piece is a straight hole without
undercut features. Because the boss 112 has to be fit into the hole
212, there is a space 214 between the thermoplastic piece and the
metal piece prior to the heat staking process. Because the heat
staking process is directed to forming the mushroom cap, the space
214 between the boss and the hole still exists after the heat
staking process.
[0007] The technique has shortcomings including, and not limited
to, relatively high labor and other cost associated with formation
of thermoplastic pieces by injection molding. Because the geometry
of the thermoplastic piece is complicated by the boss, molds having
corresponding features have to be made to accommodate the boss.
SUMMARY
[0008] The present technology relates to an ultrasonic welding
technique including applying ultrasonic energy to thermoplastic
polymer in a sheet material to fill existing hole(s) in a
dissimilar sheet material. The dissimilar sheet material has a
melting/softening temperature that is higher than the thermoplastic
sheet material. The polymer from the sheet material that filled the
hole of the dissimilar sheet material forms a weld point to create
mechanical interlock between the two sheets.
[0009] The disclosed method enables joining of a thermoplastic
composite with dissimilar sheet material without using a fastener.
It reduces complexity and cost associated with molding and handling
of the boss-bearing thermoplastic piece of traditional ultrasonic
heat staking.
[0010] Benefits of the technique include, and are not limited to,
reduced overall production time and cost in joining dissimilar
sheet materials. And a variety of joints can be formed with the
technique disclosed herein.
[0011] Time and cost are saved, for instance, because a special
mold is not needed to create a boss-bearing thermoplastic piece.
The previous need of producing various thermoplastic pieces, having
a variety of boss configurations, has been replaced with much
simpler and cost-effective approaches, in various embodiments
including drilling or punching holes in the dissimilar piece. The
ultrasonic welding of dissimilar sheet materials disclosed herein
supports lightweight strategy in vehicle manufacturing through
mixed materials joining.
[0012] Other aspects of the present technology will be in part
apparent and in part pointed out hereinafter.
DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a diagram illustrating a process of joining two
pieces of dissimilar sheet materials by a heat staking process.
[0014] FIG. 2 is a diagram illustrating a process of joining two
pieces of dissimilar sheet materials by an ultrasonic welding
process according to one embodiment of the present disclosure.
[0015] FIG. 3A is a diagram illustrating a cross sectional side
view of a thermoplastic piece being welded together with a metal
piece using a concave anvil and a sonotrode.
[0016] FIG. 3B is a cross sectional side view of a thermoplastic
piece being welded together with a first metal piece and a second
metal piece using a concave anvil and a sonotrode.
[0017] FIG. 4A is a cross sectional side view of a blind hole with
internal thread as an undercut feature in a metal piece.
[0018] FIG. 4B is a cross sectional side view of a through hole
with internal thread as an undercut feature in a metal piece.
[0019] FIG. 4C is a top view of a hole with a number of slots in a
metal piece to increase polymer-metal binding area.
[0020] FIG. 4D is a top view of an array of through holes in a
metal piece to increase polymer-metal binding strength.
[0021] FIG. 4D1 is a cross sectional side view of the metal piece
of FIG. 4D along the 1-1 line.
[0022] FIG. 5A is a diagram illustrating the first half of a
process of using an anvil with an integrated, embedded cutter to
make undercuts in a straight un-threaded hole for adding strength
in the welded piece.
[0023] FIG. 5B is a diagram illustrating the second half of the
process of FIG. 5A.
[0024] FIG. 6A is a cross sectional side view of a metal piece
being sandwiched and joined with two thermoplastic pieces through
applying ultrasonic energy to one of the thermoplastic pieces.
[0025] FIG. 6B is a diagram illustrating a side view of a two-step
process of a metal piece being sandwiched and joined with two
thermoplastic pieces.
[0026] FIG. 6B1 is a cross sectional top view of the metal piece of
FIG. 6B along the 1-1 line.
[0027] FIG. 7A is a top view of two butting metal pieces with an
array of small holes.
[0028] FIG. 7B is a cross sectional side view of the two butting
metal halves of FIG. 7A, taken along the 1-1 line, being
ultrasonically welded with a thermoplastic piece on a concave
anvil.
[0029] FIG. 8A is a top view of a sample metal piece having a
2.times.2 array of through holes.
[0030] FIG. 8A1 is a cross sectional side view of the metal piece
of FIG. 8A along the 1-1 line.
[0031] FIG. 8B is a photo of the four-hole metal piece of FIG. 8A
joined with a thermoplastic piece.
[0032] FIG. 9A shows max load data, for the four example welded
pieces, plotted against the number of weld point(s) in each
piece.
[0033] FIG. 9B shows shear strength, of the joints of all four
welded pieces, plotted against the number of weld point(s) in each
piece.
DETAILED DESCRIPTION
[0034] As required, detailed embodiments of the present disclosure
are disclosed herein. The disclosed embodiments are merely examples
that may be embodied in various and alternative forms, and
combinations thereof. As used herein, for example, "exemplary," and
similar terms, refer expansively to embodiments that serve as an
illustration, specimen, model or pattern.
[0035] The figures are not necessarily to scale and some features
may be exaggerated or minimized, such as to show details of
particular components. In some instances, well-known components,
systems, materials or methods have not been described in detail in
order to avoid obscuring the present disclosure. Therefore,
specific structural and functional details disclosed herein are not
to be interpreted as limiting, but merely as a basis for the claims
and as a representative basis for teaching one skilled in the art
to variously employ the present disclosure.
[0036] While the description includes a general context of
computer-executable instructions, the present disclosure can also
be implemented in combination with other program modules and/or as
a combination of hardware and software. The term "application," or
variants thereof, is used expansively herein to include routines,
program modules, programs, components, data structures, algorithms,
and the like. Applications can be implemented on various system
configurations, including single-processor or multiprocessor
systems, microprocessor-based electronics, combinations thereof,
and the like. In certain embodiments, some or all operations (e.g.,
controlling horn movement and energy application) are performed by,
or at least initiated by a computing device, such as a processor
executing computer-executable instructions stored or included at a
computer-readable medium. And any one or more steps of the process
can be performed, initiated, or otherwise facilitated by automated
machinery, such as robotics.
I. GENERAL OVERVIEW OF THE DISCLOSURE
[0037] The present disclosure describes an ultrasonic welding
technique for joining dissimilar-material workpieces, such as a
thermoplastic composite and a metal.
[0038] The method comprises applying ultrasonic energy to a
thermoplastic piece to fill an existing hole of a dissimilar piece,
such as metal, to form a weld point. The weld point comprises
polymer from the thermoplastic piece and provides mechanical
interlock between the dissimilar materials. In various embodiments,
two pieces are joined. In other embodiments, three or more pieces
are joined.
[0039] In general, the second, dissimilar-material workpiece has a
melting/softening temperature that is higher than the thermoplastic
workpiece. Example materials for the second workpiece include
metal, thermo-set composites, and other thermoplastics having a
higher melting temperature than the first, thermoplastic workpiece.
The workpieces being joined are referred to at times herein as
sheets, but are not limited to being a sheet or to any specific
geometry. The workpieces can have any of a wide variety of shapes
and sizes allowing performance of the present technology.
Throughout the present disclosure, the second, dissimilar-material
is also at times referred to as the higher melting temperate (HMT)
sheet or piece.
[0040] The system components, algorithm, and operations are
described further below with reference to the figures.
II. PROCESS, SYSTEM COMPONENTS, AND WORKPIECES--FIGS. 2-9B
[0041] The present technology is now described with reference to
example systems, tooling, and workpieces. The figures are
referenced to facilitate understanding of the technology, and not
to limit scope thereof.
[0042] Reference to directions herein, such as upper, lower, up,
down, and lateral, are provided to facilitate description of the
present technology but does not limit scope of the technology. A
description in which a horn is described as descending down upon a
proximate workpiece is not limited, for example, to the horn moving
vertically downward in the earth, or environment, frame. The horn
in this case can be moving from left to right, for example, in the
environment frame.
[0043] Turning again to the figures, and more particularly, to FIG.
2, an ultrasonic welding process according to one embodiment of the
technology is shown. The process joins a first, e.g.,
thermoplastic, piece 120 with a second, e.g., metal, piece 220 to
form a lap joint. Specifically, the metal piece 220 comprises a
through hole 222 that has a step undercut feature 224, a top
opening 222a, and a bottom opening 222b. The step undercut feature
224 advantageously gives the hole 222 a smaller (e.g., smaller
diameter) top opening 222a than bottom opening 222b. The
thermoplastic piece 120 is thermoplastic composite that comprises
embedded fibers 122 having a length that is less than 50% of the
diameter of the top opening 222a. The pieces 120, 220 are then
assembled 314 on a flat anvil 420 such that the thermoplastic piece
120 is overlaid on top of the metal piece 220, covering the hole
222, with the top opening 222a immediately below the thermoplastic
piece and the bottom opening 222b immediately above the surface of
the flat anvil. The stacked pieces 30 are in various embodiments
further secured with clamps 422 and 424.
[0044] A welding horn or sonotrode 440 is placed 316 on the
thermoplastic piece 120 directly above the openings 222a and 222b
in the third arrangement or step 40. The welding horn or sonotrode
440 in various embodiments has a lateral size, e.g., diameter,
being larger than the top and bottom openings 222a and 222b.
Ultrasonic energy is applied by way of the sonotrode 440 to melt or
soften the thermoplastic to fill the hole 222 with thermoplastic
from the thermoplastic piece 120. After the hole 222 is filled with
thermoplastic, the ultrasonic energy is terminated and the
sonotrode removed 318 as shown in the fourth arrangement or step
50. Because the hole 222 is filled by ultrasonic welding, the
thermoplastic forms direct contact with the wall of the hole,
filling all the undercut feature(s) in the hole, in this case, the
step undercut feature 224, leaving no gaps between the metal piece
220 and the thermoplastic piece 120 to create a weld point 126.
After cooling, the weld point 126 integrally connected with the
thermoplastic piece 120 provides mechanical interlock to join the
thermoplastic piece 120 with the metal piece 220 to form a welded
piece. The surface 124 of the weld point 126 is flush with an
adjacent lower surface of the metal piece 220 because of the flat
anvil 420 employed. The joining of the pieces is in various
embodiments further enhanced by applying adhesive between the two
dissimilar sheet materials.
[0045] The thermoplastic generally refers to a plastic material or
polymer that becomes pliable or moldable above a specific
temperature and solidifies upon cooling. For example, suitable
thermoplastic includes acrylic, acrylonitrile butadiene styrene,
polyamide, polylactic acid, polybenzimidazole, polycarbonate,
polyether sulfone, polyether ether ketone, polyetherimide,
polyethylene, polyphenylene oxide, polyphenylene sulfide,
polypropylene, polystyrene, polyvinyl chloride, and
polytetrafluoroethylene. The thermoplastic may be reinforced with
fibers such as glass, carbon, aramid, or basalt. In the ultrasonic
welding process described herein, thermoplastic composite used to
join the HMT piece has fibers having length that is less than 1/3
of the diameter of the existing hole of the dissimilar sheet
material. The existing hole can have a diameter between about 0.2
mm to 20 mm, for example, between about 0.2 mm to 0.5 mm, between
about 0.5 mm to 1 mm, between about 1 mm to 2 mm, between about 2
mm to 5 mm, between about 5 mm to 10 mm, or about between 10 mm and
20 mm. The existing hole can have a depth between about 0.2 mm to
20 mm, for example between about 0.2 mm to 0.5 mm, between about
0.5 mm to 1 mm, between about 1 mm to 2 mm, between about 2 mm to 5
mm, between about 5 mm to 10 mm, or about between 10 mm and 20
mm.
[0046] Although metal has been used as the dissimilar sheet
material throughout the illustrations and examples in the present
disclosure, it is understood that such representation does not
limit the HMT piece to metal only. Alternative HMT material such as
thermo-set composites and thermoplastic material having a higher
melting temperature than the first, thermoplastic workpiece can
also be used as the dissimilar sheet material. For example,
suitable metal includes aluminum, aluminum alloy, and steel such as
stainless steel; suitable thermoset polymers include polyester,
polyurethanes, vulcanized rubber,
polyoxybenzylmethylenglycolanhydride, urea-formaldehyde, phenol
formaldehyde melamine based material, diallyl-phthalate (DAP),
epoxy, polyimides, cyanate esters or polycyanurates. The thermoset
polymers may be reinforced with fibers such as glass, carbon,
aramid, or basalt.
[0047] In general, the geometry of the thermoplastic piece is not
altered during the process because the ultrasonic energy applied is
relatively brief as compared to for example the heat staking
process and the amount of the thermoplastic material used to fill
the hole is negligible compared to the entire thermoplastic piece
used.
[0048] The ultrasonic welding technique disclosed herein to join a
thermoplastic piece with a HMT thermoplastic piece provides an
alternative to existing thermoplastic joining techniques such as
fastening (using mechanical fasteners, for instance), adhesive
bonding, solvent bonding, co-consolidation, and fusion bonding or
welding. In some embodiments, the ultrasonic welding technique
disclosed herein can be used in conjunction with such traditional
joining techniques, to further strengthen the mechanic interlock
between the dissimilar pieces, as mentioned above regarding using
an adhesive.
[0049] Joints having only one weld point, such as the one
illustrated in FIG. 2, can provide a hinge between the two
workpieces 120, 220. Two or more weld points create torsional
constraint to produce constrained joint, such as that illustrated
in FIGS. 7A and 8A.
[0050] Referring to FIG. 3A, a cross sectional side view of a
thermoplastic piece 130 being welded together with a metal piece
230 using a concave anvil 422 and a sonotrode 442 is shown,
illustrating one embodiment of the technology. Upon sonication,
thermoplastic from the thermoplastic piece 130 fills a hole 232 of
the metal piece 230 and the illustrated concavity or cave in the
concave anvil 422 to form a mushroom shaped weld point 134 that
joins the two pieces together. While the cave is shown curved or
rounded in FIG. 3A, the hole can have other shapes, such as being a
squared or more-squared concavity, without departing from the scope
of the present technology.
[0051] Because the hole 232 is filled with ultrasonic welding, the
thermoplastic forms direct contact with the wall of the hole,
leaving no gaps between the metal piece 230 and the weld point 134.
Besides the binding force between the metal piece and the
thermoplastic piece at the stem portion of the weld point 134, the
mushroom cap portion of the weld point 134 provides additional
mechanical interlock to join the two dissimilar pieces
together.
[0052] Hole patterns and geometries are designed in various
embodiments on any of a multitude of factors. In one embodiment,
for instance, hole patterns and geometries are based on the thin
and thick gage metal sheets use. For example, holes with undercut
features such as a step (e.g., step 224 in FIG. 2), internal thread
(e.g. internal thread of FIG. 4A or internal thread 270 of FIG.
4B), or undercuts or void (e.g. undercuts or void 254 of FIG. 5A),
can be used for thick metal sheet. Each hole can include more than
one undercut features (e.g., thread and step). The step does not
necessarily have to be at the bottom of the hole--it can be
positioned mid-hole, or anywhere between a top and bottom of the
hole, for instance. The undercut features in some embodiments
include one or more hole side-wall grooves, depressions, divots, or
other selectively shaped void, threading being but one example of
such side-wall voids. Generally, each undercut feature is
configured to receive thermoplastic material beneath an upper
portion, or partial ceiling or shelf, of HMT material, to keep the
thermoplastic material, once cooled, from moving up, thereby
strengthening the joint formed. While undercut features can be
formed by cutting, they can be formed in other ways, so the term
undercut is not used to limit the manner which the feature is
formed. The undercut features in the holes provide additional
mechanical interlock joining the pieces. A flat or concave anvil
420, 422 is used to create weld points having either a flat or
mushroom-like head.
[0053] Referring to FIG. 3B, a cross sectional side view of a
thermoplastic piece 140 being welded together with a first metal
piece 234 and a second metal piece 226 using a concave anvil 424
and a sonotrode 444 is shown, illustrating one embodiment of the
technology. The technique can be used to connect the thermoplastics
piece 140 to more than two HMT pieces. The first metal piece 234
comprises a hole 236 and the second metal piece 226 comprises a
hole 228. The first metal piece 234 is stacked with the second
metal piece 226 so that the holes 236, 228 align with each other.
Upon sonication, thermoplastic from the thermoplastic piece 140
fills the holes 236 and 228 and the cave in the concave anvil 424
to form a mushroom shaped weld point 144 that joins the three
pieces together. Because the holes 236, 228 are filled by
ultrasonic welding, the thermoplastic forms direct contact with the
wall of the holes, leaving no gaps between the metal pieces 234,
226 and the weld point 144. Besides the binding force between the
metal pieces and the thermoplastic piece at the stem portion of the
weld point 144, the mushroom cap portion of the weld point 144
provides additional mechanical interlock to join the three
pieces.
[0054] In some embodiments, for joining multiple layers of metal,
through holes are created in every layer except for a last layer.
In the last layer hole that has internal undercut feature is
created, undercut feature such as the step geometry shown at
reference 224 of FIG. 2. The hole in the last layer can be a
through hole or a blind hole. Upon sonication, thermoplastic from
the thermoplastic piece fills the through hole(s) and the step hole
to form a weld point that joins the pieces together. Besides the
binding force between the metal pieces and the thermoplastic piece
at the through hole(s) portion of the weld point, the step hole
portion of the weld point provides additional mechanical interlock
to join the pieces together.
[0055] Alternative hole geometries for varying metal thickness are
illustrated in FIGS. 4A-4D. Referring to FIG. 4A, a cross sectional
side view of a blind hole 262 with internal thread 264 in a metal
piece 260 is shown. During the ultrasonic welding process, the
blind hole 262 and the internal thread 264 are filled with
thermoplastic from a thermoplastic piece, creating binding force
and mechanical interlock to hold the metal piece 260 with the
thermoplastic piece.
[0056] Referring to FIG. 4B, a cross sectional side view of a
through hole 268 with internal thread 270 in a metal piece 266 is
shown. During the ultrasonic welding process described herein, the
through hole 268 and the internal thread 270 are filled with
thermoplastic from a thermoplastic piece, creating binding force
and mechanical interlock to hold the metal piece 266 with the
thermoplastic piece. The hole geometries of FIGS. 4A and 4B are
suitable for thick workpieces, for example workpieces with
thickness of >2 mm.
[0057] Referring to FIG. 4C, a top view of a hole 274 with a number
of extending portions or slots 276 in a metal piece 272 is shown.
During the ultrasonic welding process described herein, the through
hole 274 and the slots 276 are filled with thermoplastic from a
thermoplastic piece, creating binding force to join the metal piece
272 with the thermoplastic piece.
[0058] Referring to FIG. 4D, a top view of a 3.times.3 array of
through holes 282 in a metal piece 280 is shown. During the
ultrasonic welding process, the through holes 282 are filled with
thermoplastic from a thermoplastic piece, creating binding force to
join the metal piece 280 with the thermoplastic piece. The
arrangement can be configured, and the horn apply energy, so that
the holes are filled generally simultaneously, or at various times,
such as sequentially by the horn being moved (e.g., slid along the
surface of the thermoplastic, or lifted and brought back down) to
apply energy to the thermoplastic piece at various areas
thereof.
[0059] Referring to FIG. 4D1, a cross sectional side view of the
metal piece 280 along the 1-1 line of FIG. 4D is shown. The holes
282 may or may not be through holes, parallel to each other.
[0060] The hole designs of FIGS. 4C and 4D, especially arrangements
wherein the holes are through holes, are suitable for thin
workpieces, for example workpieces with thickness of less than or
equal to 2 mm.
[0061] Referring to FIG. 5A, a diagram illustrating the first half
of a process according to one embodiment of the technology to
create undercuts is shown. FIG. 5B illustrates the second half of
the process of FIG. 5A. A thermoplastic piece 150 is shown to be
stacked on top of a metal piece 250 having a straight through hole
252. A sonotrode 460 is shown to be placed directly above the hole
252 on the thermoplastic piece 150. Although the sonotrode 460 and
the thermoplastic piece 150 are shown to be stacked on top of the
metal piece, the cutting process detailed below does not require
these items to be present during the cutting process.
[0062] Specifically, An anvil 430 with an integrated, embedded
cutter 432 is used to make undercuts 254 in the straight
un-threaded hole 252 of the metal piece 250. The undercuts 254
provide added strength to the welded polymer-metal piece through
mechanical interlocking joint force. The cutter 432 includes one
more retractable cutting inserts 434 is integrated and embedded in
anvil 430. The anvil 430 comprises bushing/bearing 436 that allows
the cutter 432 to arise and rotate through anvil 430. The metal
piece 250 comprises the straight un-threaded through hole 252,
which can be premade or created using the cutter 432. In operation
350, the cutter 432 is aligned with the through hole 252 and raised
from the anvil 430 to enter the through hole. This can be done with
the cutter 432 rotating. Once the retractable cutting inserts 434
portion of the cutter 432 are positioned to make cuts in the metal
piece 250, the cutter 432 starts rotating if not already rotating,
and the cutting inserts 434 extend out into workpiece to create
undercuts 254. Once the undercuts 254 are created, the cutter 432
retracts 352 into the anvil body and the entire anvil 430 moves
upwards to provide under-support. In the subsequent ultrasonic
process 354, the sonotrode 460 is activated to fill 356 the hole
252 and undercuts 254 with polymer to form a weld point 152. After
the removal 358 of the sonotrode 460 and anvil 430, the welded
piece 70 is obtained.
[0063] The cutter-including anvil 430 is in various embodiments
configured so that a top surface of the cutter 432 ends up
generally flush with an adjacent cutter surface, as shown in the
last view of FIG. 5A, thus forming a flat anvil surface, like that
of FIG. 2. In contemplated embodiments, the cutter-including anvil
430 is shaped and sized to, when the cutter 432 is retracted, form
a void for creating an additional undercut feature, like that of
FIGS. 3A, 3B. This undercut feature can be formed by the anvil
hole, in which the cutter 432 moves, being wider (e.g., larger
diameter) than the hole 252 of the HMT, and by retracting the top
surface of the cutter 432 beneath the adjacent top surface of the
cutter-including anvil 430. The cutter 432 could further include a
concavity, for forming a mushroom shaped weld point, like the
mushroom shaped weld point 134 of FIGS. 3A and 3B.
[0064] Although the undercuts 254 are created with an integrated,
embedded cutter 432 in the present embodiment, it is understood the
embedded cutter and/or the associated anvil is not required to make
the undercuts--i.e., the undercuts can be made using other cutting
tool or method.
[0065] Referring to FIG. 6A, the figure shows a cross sectional
side view of a metal piece sandwiched by two thermoplastic pieces
to form a double lap joint through applying ultrasonic energy to at
least one of the thermoplastic pieces. The metal piece 240 is
sandwiched by a first thermoplastic piece 160 and a second
thermoplastic piece 162. The metal piece 240 has a hole 242 having
a top opening 242a and a bottom opening 242b. A sonotrode 446 is
placed on the first thermoplastic piece 160 directly above the top
opening 242a of the hole 242 to apply ultrasonic energy to the
thermoplastic pieces to fill the hole 242 with molten thermoplastic
from both of the thermoplastic pieces. The molten thermoplastic
from both thermoplastic pieces meets and fills the entire hole 242
to connect the two thermoplastic pieces. For bottom thermoplastic
piece 162, it is believed that the vibrations from the sonotrode
446 travel through the entire system and due to the hole in the
metal piece 240, an increased stress is created in the top surface
of the bottom thermoplastic piece 162. However instead of forcing
the thermoplastic into the metal piece 240, the metal piece 240 is
being forced into the thermoplastic piece 162. A pressure gradient
is thus created, creating flow of the molten bottom piece 160 into
the hole in the metal piece 240. Upon cooling of the polymer, a
double lap joint is created with two thermoplastic pieces
sandwiching a metal piece. Although no undercut features are shown
in FIG. 6A, it is understood the hole in the metal piece 240 can be
a through hole with or without undercut features.
[0066] To create double lap shear in two independent steps, two
sets of holes are drilled to have a step geometry, one set closely
grouped and one set spaced out in the dissimilar sheet material. A
first thermoplastic sheet material is joined to the dissimilar
sheet material using a small horn and closely grouped holes. The
entire assembly is then cooled and turned--e.g., flipped over, and
then, a second thermoplastic sheet material is joined to the
dissimilar sheet material using a large horn and spaced out group
of holes. For example, referring to FIG. 6B, a diagram illustrating
a side view of a two-step process of a metal piece 244 being
sandwiched and joined with two thermoplastic pieces 164 and 166 is
shown. The metal piece 244 is sandwiched between the first
thermoplastic piece 164 and the second thermoplastic piece 166 to
form an assembly 60. The top surface 244a of the metal piece 244
contacts the first thermoplastic piece 164 and the bottom surface
244b contacts the second thermoplastic piece 166. A top cross
sectional view of the metal piece 244 along 1-1 line of FIG. 6B is
shown in FIG. 6B1. The piece 244 is shown to have a first set of
closely grouped holes 246 and a second set of spaced apart holes
248. In the first step, a sonotrode 448 is placed on the first
thermoplastic piece 164 directly above the first set of holes 246
to apply ultrasonic energy to the first thermoplastic piece 164 to
fill the first set of holes 246 with molten thermoplastic. After
the thermoplastic is cooled and set in holes 246, the assembly 60
is flipped 180.degree. and a second sonotrode 450 is placed on the
second thermoplastic piece 166 directly above the second set of
holes 248 to apply ultrasonic energy to the second thermoplastic
piece 166 to fill the second set of holes 248 with molten
thermoplastic. The first set of holes 246 are closely grouped and
the second set of holes 248 are spaced out. Accordingly, the
sonotrode 448 has a smaller diameter than the sonotrode 450 such
that the closely group holes 246 are covered entirely under the
sonotrode 448 during the first sonication step and the spaced out
holes 248 are covered entirely under the sonotrode 450 during
second sonication step. Upon cooling of the polymer, a double lap
joint is created with two thermoplastic pieces sandwiching a metal
piece. Although no undercut features are shown in FIG. 6B, 6B1, it
is understood that any of the holes 246, 248 in the metal piece 244
can be a through hole with or without undercut features.
[0067] In a contemplated embodiment, the holes have other
arrangements, such as there being only one hole in both or one of
the groups 246, 248, or by the holes being arranged other than by a
close grouped 246 and a spaced group 248.
[0068] In another contemplated embodiment, the first group of holes
are blind in one direction (e.g., having a bottom in the view of
FIG. 6B) and the second group of holes are blind in the opposite
direction (e.g., having a top in the view of FIG. 6B). In this
manner, the same sized sonotrode--e.g., horn 450--can be used in
both steps. The holes can have undercut features, such as threads,
to strengthen the connection.
[0069] Referring to FIG. 7A, the figure shows a top view of two
butting metal halves 290a, 290b with arrays of small holes 292a and
292b. Specifically, metal half 290a comprises a 3.times.6 array of
small through holes 292a and metal half 290b comprises a 3.times.6
array of small through holes 292b. The ends of the metal halves
that contain the arrays of small holes align and abut each other
such that the holes 292a, 292b together form an array 292.
[0070] Referring to FIG. 7B, the figure shows a cross sectional
side view of the two butting metal halves 290a, 290b of FIG. 7A
being ultrasonically welded with a thermoplastic piece 180 on a
concave anvil 438. Sonotrode 452 is placed directly above and
covers the array 292 and the holes 292a, 292b are filled with
thermoplastic from thermoplastic piece 180 to form weld points 182.
The weld points array collectively has a mushroom cap 184
connecting all the weld points 182, providing additional mechanical
interlocking strength to the joined pieces.
EXAMPLES
[0071] The following experimental setups are merely examples to
illustrate features of the technology, and the invention is not
limited to aspects of the examples, unless the features are
expressly claimed. The experimental setup includes a process used
to join and test 6061 aluminum with short carbon-fiber reinforced
thermoplastic (CFRP). The joint was overlapped in the lap-joint
configuration. The joint was then put in shear until failure, and
the max loads were recorded. The max loads were used to calculate
the shear strength of each joint.
[0072] Specifically, thin bars of 6061 aluminum were purchased and
cut to several samples of dimensions 38.1 mm.times.127
mm.times.3.175 mm (W.times.L.times.H). A carbon-fiber reinforced
Nylon composite material Nylon 66 were injected into mold of 38.1
mm.times.127 mm.times.3.175 mm (W.times.L.times.H) dimensions to
create thermoplastic pieces of identical dimensions and
composition. The metal sample piece was then processed to drill
holes that will be used for the joining process. Metal sample
pieces having 1 hole, 2 holes, 3 holes, and 4 holes were prepared
and all the holes has the same size and geometry. Four identical
thermoplastic pieces of the same dimensions as the metal piece were
used to join the metal pieces following the process described
below.
[0073] Using the 4 hole metal piece as an example, each hole 296
was at least 12.7 mm center to center from every other hole in the
pattern and each pattern was centered 19 mm from either edge at one
end of the metal sample piece 294 as shown in FIG. 8A. Each of the
holes 296 was of the same undercut geometry shown in FIG. 8A1.
Specifically, a portion of a cross sectional side view of FIG. 8A
along the 1-1 line is shown in FIG. 8A1. This undercut geometry of
the hole 296 was created using an 82.degree. countersink. Each hole
296 was made of a single diameter section of hole that measures
3.175 mm in diameter. This portion of the hole extends half of the
thickness of the metal sample piece 294. The remaining thickness of
the hole has a varying diameter sections that was created using the
82.degree. countersink. The hole 296 thus has a top opening 296a
that is 3.175 mm in diameter and a bottom opening 296b that is
5.944 mm in diameter.
[0074] An array of four holes 296 were drilled into the metal
sample piece 294. The metal sample piece 294 was then overlaid with
a composite sample piece 190 in a lap-joint configurations such
that there was a 38.1 mm.times.38.1 mm overlap between the two
pieces. It should be noted that the composite 190 should be the top
layer of the assembled system and it should be in contact with the
top opening 296a of the drilled metal sample piece holes as denoted
in FIG. 8A1. The assembled two pieces was then clamped within a
fixture such as those illustrated in FIG. 2 and then bolted in
place underneath an ultrasonic horn made of hardened steel that is
19 mm in diameter.
[0075] There are six parameters that were set for the ultrasonic
process. These six parameters are ultrasonic frequency, weld
energy, trigger force, hold time, amplitude % and weld speed. An
example of a set of parameters that can be used in shown in Table
1.
[0076] Table 1: Welding Parameters used for the four hole pattern
shown in FIG. 8B.
TABLE-US-00001 TABLE 1 Welding Parameter Value Ultrasonic frequency
15 kHz-30 kHz Weld Energy 1800 J Trigger Force 50 lb. Hold Time 5
sec. Amplitude % 100% Weld Speed 0.508 mm/min
[0077] Once the parameters were set, the joining process began.
Once the joints were been created, the welded piece was allowed to
fully cool for 2 hours to make sure that the excess heat from the
joining process does not affect the strength test results. Once the
welded piece cooled, it was clamped into a tensile test machine. A
photo of the welded piece is shown in FIG. 8B showing the metal
piece 294 joined with the thermoplastic piece 190 and the four weld
points 298 flush with the surface of the metal piece.
[0078] Spacers were used to center the load at the interfaces and
reduce any large effects from a bending moment created due to the
lap-joint. The tensile test machine then sheared the two pieces
apart at an extension rate of 5 mm/min. The load was recorded
during this process and the max load is saved for further
calculations. The shear area was calculated using the diameter of
296a and multiplied by the number of holes in the pattern. The max
load was then divided by the calculated shear area to calculate the
shear strength of the joint.
[0079] The processes described above were repeated to join each of
the 1 hole, 2 hole, and 3 hole metal pieces with an identical
thermoplastic piece made above to create welded pieces having 1, 2,
and 3 welding points respectively. The welded pieces were then
tested following the same testing procedure outlined above to
obtain max load and shear strength of the joint. The max load data
from all four welded pieces are shown in FIG. 9A and the shear
strength of the joint data are shown in FIG. 9B.
[0080] Similar experiments were conducted using 3 mm thick short
carbon-fiber reinforced thermoplastic (CFRP) and 1 or 3 mm aluminum
sheets. The results are shown in Table 2 below.
TABLE-US-00002 TABLE 2 Aluminum CFRP No. of Hole Max Load sheet
thickness Hole diameter (Lap Shear) (mm) (mm) (s) (mm) (N) 1 3 1 3
500 1 3 2 3 864 1 3 3 3 1400 3 3 3 3 1397
III. ADVANTAGES OF IMPLEMENTATION
[0081] Many of the advantage of the present technology are outlined
above. Some are described further in this summary.
[0082] Benefits include reduced production time and cost. The
benefits make ultrasonic welding of dissimilar sheet materials more
cost effective, and manufacturing of lightweight parts and products
(e.g., vehicles) more cost effective.
[0083] Time and cost are saved, for instance, by obviating need for
a manufacturing mold to form a boss-bearing thermoplastic
piece.
[0084] Besides providing alternative processes to join dissimilar
sheet materials, the ultrasonic welding process disclosed herein
may be used to complement existing process in joining dissimilar
sheet materials.
IV. CONCLUSION
[0085] Various embodiments of the present disclosure are disclosed
herein. The disclosed embodiments are merely examples that may be
embodied in various and alternative forms, and combinations
thereof. As used herein, for example, "exemplary," and similar
terms, refer expansively to embodiments that serve as an
illustration, specimen, model or pattern.
[0086] The figures are not necessarily to scale and some features
may be exaggerated or minimized, such as to show details of
particular components. In some instances, well-known components,
systems, materials or methods have not been described in detail in
order to avoid obscuring the present disclosure. Therefore,
specific structural and functional details disclosed herein are not
to be interpreted as limiting, but merely as a basis for the
technology foci (e.g., claims) and as a representative basis for
teaching one skilled in the art.
[0087] The law does not require and it is economically prohibitive
to illustrate and teach every possible embodiment of the present
technology foci (e.g., claims). Hence, the above-described
embodiments are merely exemplary illustrations of implementations
set forth for a clear understanding of the principles of the
disclosure. Variations, modifications, and combinations may be made
to the above-described embodiments without departing from the scope
of the technology foci (e.g., claims). All such variations,
modifications, and combinations are included herein by the scope of
this disclosure and the following technology foci (e.g.,
claims).
* * * * *