U.S. patent application number 17/667138 was filed with the patent office on 2022-07-21 for multi-layer laminate load ring.
The applicant listed for this patent is Aerostar International, Inc.. Invention is credited to Daniel Fourie.
Application Number | 20220228613 17/667138 |
Document ID | / |
Family ID | 1000006245152 |
Filed Date | 2022-07-21 |
United States Patent
Application |
20220228613 |
Kind Code |
A1 |
Fourie; Daniel |
July 21, 2022 |
MULTI-LAYER LAMINATE LOAD RING
Abstract
A laminated load ring for a balloon assembly includes a
plurality of ring stacking units stacked one on top of the other.
Each of the ring stacking units can include a main body having a
central opening, a plurality of arms, and at least one weld line.
The plurality of arms may each extend away from the main body
around a circumference of the main body. The at least one weld line
can be formed on the main body. The plurality of arms of the
plurality of ring stacking units may be aligned with one another.
The weld line of each of the plurality of ring stacking units may
be offset from the weld line of a directly adjacent ring stacking
unit in a direction extending around the circumference of the
laminated load ring.
Inventors: |
Fourie; Daniel; (Sunnyvale,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Aerostar International, Inc. |
Sioux Falls |
SD |
US |
|
|
Family ID: |
1000006245152 |
Appl. No.: |
17/667138 |
Filed: |
February 8, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16858772 |
Apr 27, 2020 |
11268555 |
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17667138 |
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16261079 |
Jan 29, 2019 |
10670062 |
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16858772 |
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15053505 |
Feb 25, 2016 |
10253795 |
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16261079 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B64B 1/58 20130101; Y10T
403/477 20150115; F16B 11/006 20130101; B64B 1/42 20130101; B64B
1/40 20130101; F16B 5/08 20130101; Y10T 29/49826 20150115 |
International
Class: |
F16B 5/08 20060101
F16B005/08; B64B 1/40 20060101 B64B001/40; F16B 11/00 20060101
F16B011/00; B64B 1/58 20060101 B64B001/58 |
Claims
1. (canceled)
2. A fiber-reinforced load ring comprising: a central opening; an
interior edge surrounding the central opening; and a perimeter edge
surrounding the interior edge; a plurality of projecting arms
extending from the perimeter edge and away from the central
opening; wherein each of the arms includes: a distal end; and an
aperture extending through the distal end.
3. The fiber-reinforced load ring of claim 2 wherein fibers of the
fiber-reinforced load ring are oriented in a lateral direction
nearly parallel to a top or a bottom surface of the
fiber-reinforced load ring.
4. The fiber-reinforced load ring of claim 2 wherein fibers within
the fiber-reinforced load ring are oriented in substantially the
same direction.
5. The fiber-reinforced load ring of claim 2 wherein at least 25%
of fibers within the fiber-reinforced load ring are oriented in the
same direction.
6. The fiber-reinforced load ring of claim 2 wherein the
fiber-reinforced load ring is an injection molded ring.
7. The fiber-reinforced load ring of claim 2 wherein the
fiber-reinforced load ring is made from a high-performance
thermoplastic.
8. The fiber-reinforced load ring of claim 2 wherein the
fiber-reinforced load ring is made from at least one of high
strength glass-fiber, carbon-fiber, or ceramic fiber filled
nylon-based plastic.
9. The fiber-reinforced load ring of claim 2 further comprising at
least one gate extending from the interior edge towards a center of
the central opening.
10. The fiber-reinforced load ring of claim 2 wherein at least two
fiber-reinforced load rings are stacked.
11. The fiber-reinforced load ring of claim 10 wherein the at least
two fiber-reinforced load rings are bonded together.
12. The fiber-reinforced load ring of claim 2 further comprising
bolts received through at least one of the apertures.
13. The fiber-reinforced load ring of claim 2 further comprising at
least one tendon coupled to the fiber-reinforced load ring through
at least one of the apertures.
14. The fiber-reinforced load ring of claim 2 wherein a termination
plate assembly disposed at a base of a balloon envelope or an apex
of a balloon envelope is coupled to the fiber-reinforced load ring.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 16/261,079, filed on Jan. 29, 2019, which is a
continuation of U.S. patent application Ser. No. 15/053,505, filed
on Feb. 25, 2016, now issued as U.S. Pat. No. 10,253,795 issued.
April 9, 2019, the disclosures of which are incorporated herein by
reference.
BACKGROUND OF THE INVENTION
[0002] Computing devices such as personal computers, laptop
computers, tablet computers, cellular phones, and countless types
of Internet-capable devices are increasingly prevalent in numerous
aspects of modem life. As such, the demand for data connectivity
via the Internet, cellular data networks, and other such networks,
is growing. However, there are many areas of the world where data
connectivity is still unavailable, or if available, is unreliable
and/or costly. Accordingly, additional network infrastructure is
desirable.
[0003] Some systems may provide network access via a balloon
network operating in the stratosphere. Because of the various
forces experienced by these balloons during deployment and
operation, there is a balancing of needs between flexibility and
stability of materials. As such, the balloons include a number of
components, such as a flexible envelope made of material that may
be configured in sections or lobes to create a "pumpkin" or lobed
balloon, a plurality of tendons to support the lobes and a
termination plate or load ring for securing the tendons to the
balloon. The load ring functions to support an anticipated tendon
load created during balloon envelope inflation by transferring the
load of one tendon to the opposite tendon on the other side of the
balloon apex through hoop stress in the load ring.
SUMMARY OF THE INVENTION
[0004] According to aspects of the disclosure, a laminated load
ring for a balloon assembly includes a plurality of ring stacking
units stacked one on top of the other. Each of the ring stacking
units includes a main body that has a central opening, a plurality
of arms that each extends away from the main body around a
circumference of the main body, and at least one weld line formed
on the main body. The plurality of arms of the plurality of ring
stacking units may be aligned with one another, and the weld line
of each of the plurality of ring stacking units may be offset from
the weld line of a directly adjacent ring stacking unit in a
direction extending around the circumference of the laminated load
ring.
[0005] In one embodiment of this aspect, each of the ring stacking
units may be manufactured from a fiber-reinforced material. The
majority of the fibers in the ring stacking unit may be oriented in
a lateral direction that extends in a direction parallel to a top
surface of the ring stacking unit. The at least one weld line of
each of the plurality of ring stacking units can be spaced apart
from the at least one weld line of the directly adjacent ring
stacking unit by a same distance. Each of the ring stacking units
can further include at least one gate tab that is positioned within
the central opening. The at least one gate tab of each of the
plurality of ring stacking units can be offset by at least five
degrees from the at least one gate tab of the directly adjacent
ring stacking unit in a direction extending around the
circumference of the laminated load ring. The main body can have a
thickness of at least 0.050 inches.
[0006] According to another embodiment of this aspect, a thickness
of each ring stacking unit is at least 0.060 inches.
[0007] According to another embodiment of this aspect, each of the
plurality of ring stacking units can have a circumferential tensile
strength of at least 100 MPa. A sum of the strength of each of the
plurality of ring stacking units in the laminated load ring can be
less than the overall strength of the assembled laminated load
ring.
[0008] According to another embodiment of this aspect, the
plurality of ring stacking units may be bonded together. In one
example, an adhesive layer may be provided between each of the
plurality of ring stacking units. In another example, the plurality
of ring stacking units may be additionally or alternatively
ultrasonically welded together.
[0009] According to another aspect of the disclosure, an in-process
laminated load. ring unit for a balloon assembly includes a
plurality of identical ring stacking units stacked one on top of
the other and a plurality of gates tabs. Each of the ring stacking
units may be manufactured from a fiber-reinforced material, wherein
each of the ring stacking units includes a main body having a
central opening and an interior edge forming a periphery around the
central opening. The fibers in the fiber-reinforced material may be
oriented in substantially the same direction. The plurality of
gates tabs may extend away from the interior edge. Each of the
plurality of gate tabs may be offset from a directly adjacent gate
tab of the plurality of gate tabs in a direction extending around
the circumference of the laminated load ring. In one example, the
gate tabs may be evenly spaced apart from one another. In another
example, each of the plurality of gate tabs can extend continuously
from the main body. In still another example, the gate tabs may
have a thickness that is a same thickness as a thickness of the
main body.
[0010] In accordance with another embodiment of this aspect, a
thickness of each ring stacking unit is at least 0.060 inches.
[0011] In yet another embodiment of this aspect, a majority of the
fibers in the ring stacking unit are oriented in a lateral
direction that is parallel to a top surface of the ring stacking
unit.
[0012] A method of forming a laminated load ring according to
aspects of the disclosure includes providing a plurality of ring
stacking units, stacking a second ring stacking unit of the
plurality of ring stacking units on top of a first ring stacking
unit; and arranging the first and second ring stacking units. Each
of the ring stacking units may be substantially similar in shape
and size. Each of the ring stacking units may further include a
main body having an opening, an interior edge extending around the
opening, a plurality of arms extending around an exterior edge of
the ring stacking unit, and a weld line in the main body of the
ring stacking unit. The first and second ring stacking units may be
arranged so that the weld line of the second ring stacking unit is
offset relative to the first ring stacking unit in a direction
extending around a circumference of the ring stacking unit.
[0013] In another example of this aspect, the step of providing
further includes forming a shape of plurality of ring stacking
units from an injection mold filled with a fiber-reinforced
material. Each of the fibers in the fiber-reinforced material is
oriented in a same direction when the injection mold is filled with
the fiber reinforced material.
[0014] The method of claim 18, wherein the plurality of arms of the
second ring stacking unit are aligned. with the plurality of arms
of the first stacking unit, the method further comprising stacking
a third ring stacking unit of the plurality of ring stacking units
on top of the second ring stacking unit so that the weld line of
the third ring stacking unit does not align with the weld line of
the second ring stacking unit.
BRIEF DESCRIPTION OF THE DRAW1NGS
[0015] FIG. 1 is a functional diagram of a system in accordance
with aspects of the present disclosure.
[0016] FIG. 2 is a view of an example of a balloon in accordance
with aspects of the present disclosure.
[0017] FIG. 3 is a cross-sectional view of an example of a
termination plate assembly that includes a load ring in accordance
with aspects of the present disclosure.
[0018] FIG. 4 is an example laminate load ring according to aspects
of the present disclosure.
[0019] FIG. 5 is an example of an injection mold system according
to aspects of the disclosure.
[0020] FIG. 6 is a perspective view of an example ring stacking
unit according to aspects of the disclosure.
[0021] FIG. 7 is an enlarged view of a portion of an individual
load ring according to aspects of the disclosure.
[0022] FIG. 8 is an exploded view of the components of FIG. 11.
[0023] FIGS. 9-10 illustrate method steps of manufacturing a load
ring according to aspects of the disclosure.
[0024] FIG. 11 illustrates a perspective view of an in-process load
ring unit according to aspects of the disclosure.
[0025] FIG. 12 is a top plan view of FIG. 11.
[0026] FIG. 13 is a cross-sectional view taken across line A-A in
FIG. 4.
[0027] FIG. 14 is an example of a flow diagram in accordance with
aspects of the present disclosure.
DETAILED DESCRIPTION OF THE DRAW1NGS
[0028] Aspects of the disclosure are directed to a cost-effective
and light-weight multi-layer laminate load ring for a balloon
envelope of a balloon assembly. Typically, load rings are metal
rings designed to be positioned on top of a balloon envelope and
connected to the balloon tendons. A typical load ring is formed
from a large monolithic piece of metal that can both efficiently
distribute the tendon load and withstand the extreme pressure of
the balloon. However, metal load rings can be heavy, reducing the
weight of a payload that the balloon is able to effectively
support, as well as extremely expensive to manufacture.
[0029] To address these shortcomings, rather than using metal, a
load ring may be a laminated modular ring made up of several
stacked layers of thin injection molded plastic rings or individual
ring stacking units, which together form a unitary laminated load
ring. The fibers of each laminate ring may be oriented to generally
face in the same direction to increase the strength of each
individual ring. Furthermore, when stacking each of the individual
rings, the rings may be offset from the next adjacent ring in a
direction extending along the circumference of the ring and
additionally or alternatively at a consistent angle. This stacked
and offset configuration reduces the likelihood of weakened
locations on the load ring caused by the formation of weld lines
and gates during the injection molding process.
[0030] The load ring may have the overall shape of a circular ring
and include a circular central opening. A plurality of tendon
receiving arms may be evenly-spaced around the perimeter of the
load ring. Each of the arms may include apertures to receive bolts.
Tendons may be attached to the load rings.
[0031] Each individual ring stacking unit can be manufactured to
have the same uniform shape and size. When stacked together, the
individual ring stacking units can form the overall shape of the
load ring. An example ring stacking unit can therefore also be
ring-shaped with a central opening and a plurality of arms
extending around the perimeter of the stacking ring. The ring
stacking unit may have a thickness extending between the top
surface and bottom surface of the stacking unit.
[0032] The individual ring stacking units can be injection molded
and formed from an injection mold that includes two or more
components joined together to form the shape of a ring. For
example, the injection mold may be comprised of four primary mold
components that together form the circular shape and arms of the
ring stacking unit, but less than four or greater than four
components may be utilized. The injection mold can include a
central opening, which forms the central opening of the ring
stacking unit. Four gates may be provided within the central
opening of the mold. Each of the four gates may intersect one
another at the center of the central opening. The gates can
therefore extend from the center of the central opening to a point
along the mold. In this example, the four gates are equally spaced
around the circumference of the mold.
[0033] The material used to form the individual ring stacking units
and that is injected into the mold may be a fiber reinforced
plastic material, although other types of material can also be
used. The reduced thickness of the individual ring stacking unit
allows for fibers in the material to achieve an optimal
orientation. This is because the thickness of the injection mold
does not provide the room for the fibers to rotate and move through
multiple axes. Substantially all of the fibers can therefore be
oriented in substantially the same direction. In one example, the
length or longest dimension of the fibers may extend laterally
along the same plane as the top and bottom surfaces of the ring
stacking unit.
[0034] At the conclusion of the injection molding process, the
individual ring stacking unit can be removed from the injection
mold. The resulting individual ring stacking unit will be in the
overall shape of the load ring.
[0035] An in-process load ring unit can be formed prior to complete
formation of the laminated load ring. During assembly of the load
ring, multiple individual ring stacking units can be stacked one on
top of the other to form an intermediate or in process unit. During
assembly, the weld lines of each ring stacking unit may be offset
by a predetermined number of degrees. Each of the subsequent ring
stacking units can also be rotated the distance between a first and
second arm so that the arms of each of the ring stacking units are
aligned with one another. This further allows for incremental
rotation of the weld lines around the laminated ring. Any number of
additional stacking units may be added to form the completed
laminated load ring.
[0036] The individual ring stacking units may be bonded together to
ensure they remain secured together. Various materials and bonding
methods can be used, such as use of an adhesive material or
welding.
[0037] Once the desired number of ring stacking units has been
assembled together, gate tabs extending around the peripheral edge
of the central opening can be removed to form the completed load
ring. In other examples, the gate tabs can be removed from the
individual ring stacking units prior to the individual ring
stacking unit being stacked to form the completed and laminated
load ring. Additional finishing procedures can be further
completed, such as sanding the edges of the ring stacking unit to
form smooth edges, removing excess adhesive, and the like.
[0038] The load ring with offset weld lines can have a strength
that is greater than the laminated load ring wherein each of the
weld lines of the ring stacking units are aligned with one another.
This is due, in part, to the fact that the fibers in each ring
stacking unit may be oriented in the same or similar direction,
which increases the overall strength of laminated load ring when
each of the individual ring stacking units are bonded together.
Additionally, because the weld lines of each adjacent stacking unit
are not aligned with one another, the locally weak points of one
ring stacking unit are offset from the locally weak point of an
adjacent ring stacking unit. In this regard, the locally weak point
of one ring can be strengthened by the adjacent ring stacking unit
which overlies the locally weak point. Finally, the load ring can
be significantly lighter than metal load rings while maintaining
strength properties due to the configuration.
Example System
[0039] FIG. 1 depicts an example system 100 in which a balloon
assembled according to aspects herein may be used. This example
should not be considered as limiting the scope of the disclosure or
usefulness of the features of the present disclosure. For example,
the techniques described herein can be employed on various types of
standalone balloons or balloons used with other types of systems.
In this example, system 100 may be considered a "balloon network."
The balloon network 100 includes a plurality of devices, such as
balloons 102A-F, ground base stations 106 and 112 and links 104,
108, 110 and 114 that are used to facilitate intra-balloon
communications as well as communications between the base stations
and the balloons. One example of a balloon is discussed in greater
detail below with reference to FIG. 2.
Example Balloon
[0040] FIG. 2 is an example balloon 200, which may represent any of
the balloons of balloon network 100. As shown, the balloon 200
includes a balloon envelope 210 comprised of envelope gores 210A,
210B, 210C, 210D, a payload 220 and a plurality of tendons 230
attached to the envelope 210 and a termination plate 201 at the
apex 242 of the balloon.
[0041] The balloon envelope 210 may take various forms. In one
instance, the balloon envelope 210 may be constructed from
materials such as polyethylene that do not hold much load while the
balloon 200 is floating in the air during flight. Additionally, or
alternatively, some or all of balloon envelope 210 may be
constructed from a highly flexible latex material or rubber
material such as chloroprene. Other materials or combinations
thereof may also be employed. Further, the shape and size of the
balloon envelope 210 may vary depending upon the particular
implementation. Additionally, the balloon envelope 210 may be
filled with various gases or mixtures thereof, such as helium,
hydrogen or any other lighter-than-air gas. The balloon. envelope
210 is thus arranged to have an associated upward buoyancy force
during deployment of the payload 220.
[0042] The payload 220 of balloon 200 is affixed to the envelope by
a connection such as a cable (not shown). The payload 220 may
include a computer system (not shown), having one or more
processors and on-board data storage. The payload 220 may also
include various other types of equipment and systems (not shown).
For example, the payload 220 may include an optical communication
system, a navigation system, a positioning system, a lighting
system, an altitude control system and a power supply to supply
power to various components of balloon 200.
[0043] In view of the goal of making the balloon envelope 210 as
lightweight as possible, it may be comprised of a plurality of
envelope lobes or gores that have a thin film, such as polyethylene
or polyethylene terephthalate, which is lightweight, yet has
suitable strength properties for use as a balloon envelope
deployable in the stratosphere. In this example, balloon envelope
210 is comprised of a plurality of envelope gores 210A-210D.
[0044] Pressurized lift gas within the balloon envelope 210 may
cause a force or load to be applied to the balloon 200. In that
regard, the tendons 230 provide strength to the balloon 200 to
carrier the load created by the pressurized gas within the balloon
envelope 210. In some examples, a cage of tendons (not shown) may
be created using multiple tendons that are attached vertically and
horizontally. Each tendon may be formed as a fiber load tape that
is adhered to a respective envelope gore. Alternately, a tubular
sleeve may be adhered to the respective envelopes with the tendon
positioned within the tubular sleeve.
[0045] Each tendon may be formed as a fiber load tape that is
adhered to a respective envelope gore. Alternately, a tubular
sleeve may be adhered to the respective envelopes with the tendon
positioned within the tubular sleeve. In some examples, the tendons
230 may be run from the apex to the bottom of the balloon envelope
210 in order to pick up the load. In normal operations, these
tendons 230 need to be kept in place during balloon flight in order
to continue to handle the load and maintain the shape of the
balloon envelope.
[0046] Top ends of the tendons 230 may be coupled together using a
type of assembly, such as a termination plate assembly 201, which
may be positioned at the apex of balloon envelope 210. In some
examples, bottom ends of the tendons 230 may also be connected to
one another. For example, a corresponding termination plate 202 may
be disposed at a base or bottom of the, balloon envelope 210. The
termination plate 201 at the apex may be the same size and shape as
the termination plate 202 at the bottom of the balloon envelope
210. Both termination plates may include corresponding components
for attaching the tendons 230 thereto. In other examples, the mouth
of the bottom of the balloon envelope 210 may remain open during
use, such that the mouth is not sealed to a termination plate or
other device.
[0047] FIG. 3 is an example of a termination plate assembly 300.
Here, a side cut-way view of the termination plate assembly 300 is
shown. In this example, the termination plate assembly includes a
number of components, such as a plate body 302 having an opening
including a fill port 304, and a plurality of tendons 230 overlying
the balloon gores 306 that are attached to termination plate body
302.
[0048] Plate body 302 of the termination plate assembly 300 may be
made of a lightweight yet rigid material, such as a type of plastic
or other types of similar materials. Because the plate body 302 may
not itself be load bearing, the termination plate assembly 300 may
include a load bearing mechanism for supporting the tendons
attached to the assembly. As shown, the termination assembly 300
may include a load ring 307 that can be coupled to each tendon 230
in order to secure that tendon to the assembly 300. In some
aspects, the load ring 307 can be formed from a plurality of
laminated rings that are strong enough to support the load carried
by the tendons. This load ring 307 may be configured to reach
around the plate body 302 of termination assembly 300 in a manner
so that arms on the load ring 307 can couple each tendon to the
plate.
Example Load Ring
[0049] FIG. 4 is an example of a load ring 410 (corresponding to
load ring 307) according to an aspect of the disclosure. The load
ring 410 may have the overall shape of a circular ring and include
a circular central opening 412. A plurality of tendon receiving
arms 414 may be evenly-spaced around the perimeter of the load ring
410. Each of the arms 414 may include apertures 416 which can be
sized to receive bolts (not shown) that extend through the aperture
416 and can be used to attach other components of the balloon
assembly there to. In one example, the thickness X1 of the load
ring may be at least 0.5 inches, but can range from 0.25 to 1.25
inches. In other examples, any desired thickness may be used. The
load ring 410 may have a circumferential tensile strength of at
least 280 MPa. In other examples, the tensile strength may fall
within the range of 100 MPa-500 MPa.
[0050] The load ring 410 may be a laminated modular ring made up of
several stacked layers of individual ring stacking units. As shown,
for example, in FIG. 4, ring stacking units 420A'-420I' are stacked
one on top of the other to form a fully assembled and completed
load ring 410. The ring stacking units 420A'-420I' can each be
manufactured to have the same uniform shape and size so that when
stacked together, the collective ring stacking units 420A'-420I'
form the overall shape of the load ring 410. As will be discussed
in more detail herein, each of the ring stacking units 420A'-420H'
can have a thickness that is less than the thickness X1 of the
filly assembled load ring 410.
[0051] One or more of the ring stacking units that form the load
ring 410 can be manufactured through an injection molding process.
For example, as shown in the schematic view of FIG. 5, an injection
mold 430 can be provided to form the shape of a single ring
stacking unit, such as ring stacking unit 420A (shown in FIG. 6).
The injection mold 430 may include a central opening 432, which
will become the central opening 412A (shown in FIG. 6) of the ring
stacking unit 420A. Cavities 417 and shapes within the mold will
help to form the shape of the desired load ring 410. As shown, the
cavities 417 create the shape of the body of an individual ring
stacking unit, such as the ring stacking unit 420A, including the
ring arms of the individual ring stacking unit. Gates may be
provided within the central opening of the mold to facilitate
movement of the material forming the ring stacking unit into the
injection mold 430. In this example, four gates 434, 436, 438, and
440 are provided. Each of the four gates 434, 436, 438, and 440 may
intersect one another at what will become the center 442 of the
central opening 412A. The four gates 434, 436, 438, and 440 may be
equally spaced around the circumference of the opening of the mold
430 at approximately forty-five degrees away from one another. In.
other examples, there may be a fewer number of gates or a greater
number of gates. Additionally or alternatively, one or more of the
gates may not be evenly spaced around the mold.
[0052] During the injection molding process, a nozzle 444
positioned at the intersection of the four gates 434, 436, 438, and
440 may be used to introduce the material forming the ring stacking
unit 420 into the mold 430. The material forming the ring stacking
unit 420A can flow through the nozzle 444 into each of the four
gates 434, 436, 438, and 440. The material will continue to flow
through the gates 434, 436, 438, and 440 and into respective gate
entrances 434A, 436A, 438A, 440A positioned at the interior edge
419 of the injection mold 430. Once the material flows through the
gate entrances 434A, 436A, 438A, 440A, the material will dispense
throughout the mold 430 until two flow fronts meet at a point
generally between two gate entrances. As will be discussed herein,
the point where the two flow fronts meet can cause weld lines to
form on the ring stacking unit. The material used to form the
individual ring stacking units 420 and that is injected into the
injection mold 430 can include a fiber reinforced plastic material,
such as a high strength glass-fiber filled nylon-based plastic may
be used. Other materials that can be used to manufacture the ring
stacking unit can include glass-fiber filled, carbon-fiber filled,
ceramic-fiber filled nylon-based plastic, or any other high
performance thermoplastic.
[0053] At the conclusion of the injection molding process, the
injection mold may be removed away from the final ring stacking
unit 420A. The resulting ring stacking unit 420A can have the
overall shape of the load ring 410, but a lesser thickness. As
shown, for example, in FIG. 6, the ring stacking unit 420A has the
same shape as the completed load ring 410 (FIG. 4.) The ring
stacking unit 420A can be circular in shape and include a central
opening 412A and a plurality of arms 414A extending around the
circumference of the ring stacking unit 420A, including the first
and second ring arms 414A1 and 414A2. The ring stacking unit 420A
may have a thickness X2 extending between the top surface 422A and
bottom surface 424A of the ring stacking unit 420A. (See also FIG.
7.) The ring stacking unit 420A may have a thickness X2 that is at
least 0.060 inches, but may range from 0.040 to 0.090 inches. In
other examples, the thickness of the ring stacking unit need only
be less than the thickness X1 of the completed load ring 412 shown
in FIG. 4.
[0054] The ring stacking 420A unit can further include gate tabs
450A-D, as shown for example in FIG. 6. The gate tabs 450A-450D may
possess a generally rectangular shape that may extend away from the
interior edge 452 of the central opening 412A in a direction toward
the center 454 of the central opening 412A of the ring stacking
unit 420A. The gate tabs 450 can correspond to each of the four
gate entrances 434A, 436A, 438A, 440A attached to the injection
mold 430 as shown in FIG. 5. In other words, the gate tabs may
result from the juncture of the four gates 434, 436, 438, 440 and
the injection mold 430. In other examples, there may be less than
four gate tabs or greater than four gate tabs, or no gate tabs at
all. The gate tabs 450A-450D can further be removed before, after,
or during assembly of the load ring 412. In other examples, the
gate tabs can have a different shape.
[0055] Weld lines may also be formed along the ring stacking unit
420A. As previously noted, the weld lines occur at the point where
the two or more flow fronts introduced through two or more gates
into the mold meet with one another. In this example where the
gates are evenly spaced around the circumference of the load ring,
weld lines can appear approximately half-way between two different
gates. As shown, four weld lines are disposed within the ring
stacking unit 420A. Weld line 448A is positioned between gate tab
450A and gate tab 450B; weld line 448B is positioned between gate
tab 450B and gate tab 450C; weld line 448C is positioned between
gate tab 450C and gate tab 450D; and weld line 448D is positioned
between gate tab 450D and gate tab 450A. In other examples, where
the gates have a different spacing, the weld lines 448A-448D can be
positioned on different points of the ring.
[0056] The ring stacking unit may have a circumferential tensile
strength of at least 100 MPa. In other examples, the strength may
range between 30 MP and 200 MPa. The orientation of the fibers in
the material forming the ring stacking units 420 can contribute to
increasing the circumferential tensile strength. As shown in FIG.
7, an enlarged view of fibers orientated within the ring stacking
unit 420A, the fibers 448 of the ring stacking unit are oriented in
substantially the same direction. This orientation can result, in
part, from manufacturing the ring stacking unit 420A to have a
thickness, such as the thickness X2 between the top and bottom
surfaces 422, 424, that minimizes the ability of the fibers 448
within the material to rotate and move through multiple axes. The
length L or longest dimension of the fibers 448 may extend
laterally along a plane P that is parallel to the top surface 422A
and bottom surface 424A of the ring stacking unit 420. In addition,
the length L of the fibers 448 can be aligned circumferentially
around the ring. In other examples, a majority of the fibers in the
ring stacking unit may be oriented in the same direction or
alternatively approximately 25% or more of the fibers may be
oriented in the same direction.
[0057] The ring stacking unit 420A can be a first ring stacking
unit 420A stacked with other ring stacking units that will together
form the load ring 410 of FIG. 4. In one example, as shown in FIG.
8, which is an exploded view of FIG. 11, the ring stacking unit
420A, as well as a plurality of other substantially identical
individual ring stacking units 420B-H can be provided. In this
example, each of the ring stacking units 420B-420H are identical to
ring stacking unit 420A and may be injection molded. Each of the
ring stacking units 420B-420H can include weld lines and gate tabs
that are formed in a same location along the respective ring
stacking unit. For example, weld lines 458A-458D, gate tabs
460A-460D and a plurality of arms 414B, including first and second
arms 414B1 and 414B2, extending around the circumference of the
second ring stacking unit 420B are positioned along the same
location of the ring stacking unit 420B as each of the weld lines
448A-448D, gate tabs 450A-450D and plurality of arms 414A of the
first ring stacking unit 420A. Respective weld lines, gate tabs and
arms of each ring stacking unit 414C-E can also be aligned with the
weld lines, gate tabs and arms of the first ring stacking unit
420A. In other examples, the features of one or more ring stacking
units 420B-420H may differ from ring stacking unit 420A.
[0058] In one method of assembly, the ring stacking units are
stacked one ring stacking unit at a time, For example, the first
and second ring stacking units 420A, 420B can be first stacked
together. The second ring stacking unit 420B can initially be
aligned with the first ring stacking unit (as shown in FIG. 7) so
that each of the weld lines 458A-458D and gate tabs 460A-460D of
the second ring stacking unit 420B are aligned with each of the
weld lines 448A-448D and gate tabs 450A-450D of the first ring
stacking unit. This will also cause the first arm 414B1 of the
plurality of arms 414B of the second ring stacking unit 420B to be
aligned with the first arm 414A1 of the plurality of arms 414A of
the first ring stacking unit 420A.
[0059] In some examples, the ring stacking units can offset from
one another or rotated relative to one another during the staking.
For instance, the second ring stacking unit 420B can be rotated
relative to the first stacking unit so that the weld lines and gate
tabs of the second ring stacking unit 420B do not align with a weld
line and gate tab of a directly adjacent first ring stacking unit
420A. As shown, for example in FIG. 9, the second ring stacking
unit 420B is shown being positioned on top of the directly adjacent
ring stacking unit 420A. Ring stacking unit 420B is shown rotated
around a central axis A, which can extend through the center of the
first and second ring stacking units, relative to the first ring
stacking unit 420A, such that weld line 458D of the second ring
stacking unit is no longer aligned with the weld line 448D. In this
example, weld line 458D of the second ring stacking unit 420B and
weld line 448D of the first ring stacking unit 420A are offset by
an amount W1 relative to the first ring stacking unit 420A, as well
as along the circumference of the first ring stacking unit 420A. In
this example, W1 may be approximately 5 degrees. In other examples,
W1 can be any desired amount, such as an amount that ranges between
1-45 degrees. The degree to which the two weld lines are offset
from one another can also vary based upon how many weld lines are
present on the ring stacking unit. If only two weld lines are
equally spaced apart from one another on a circular ring, the
second weld line can be offset relative to the first ring anywhere
between 1 and 89 degrees. Although not shown, the remaining weld
lines 458B, 458C, 458D of the second ring stacking unit can be
similarly offset the same distance W1 from the respective weld
lines 448B, 448C, 448D of the first ring stacking unit 420A.
Positioning the weld lines of the second ring stacking unit so that
they do not align with the weld lines of the directly adjacent
first ring stacking unit 420A can help to offset the weakened areas
within the final laminated load ring due to the weld lines.
[0060] The rotation may also be used to account for the location of
the plurality of arms of each of the ring staking units. For
instance, the second ring stacking unit 420B can also be rotated
relative to the directly adjacent stacking unit 420A by an amount
that allows for the plurality of arms 414B of the second ring
stacking unit 420B to align with the plurality of arms 414A of the
first ring stacking unit 420A. As shown in this example, second
ring stacking unit 420B can be rotated to position first arm 414B1
of the plurality of arms 414B of the second ring stacking unit 420B
to align with the second arm 414A2 of the plurality of arms 414A of
the first ring stacking unit 420A. In such example, the first arm
414B1 of the second ring stacking unit 420B can be moved out of
alignment with the first arm 414A1 of the first ring stacking unit
420A1 and aligned with the second arm 414A2 of the first ring
stacking unit. Since the first arm 414B1 includes weld lines 458D,
first arm 414B1 can also be moved a distance W1 of at least 5
degrees. This rotation can also cause the weld line 458D of the
second ring stacking unit 420B to be offset from the weld line 448D
of the first stacking unit 420A. Each of the remaining plurality of
arms 414B of the second ring stacking unit 414B, which can be
evenly spaced around the ring stacking unit 414B, can also align
with the plurality of arms 414A of the first ring stacking unit
420A. In still other examples, the second ring stacking unit 420B
can move the distance between two or more arms. For example, the
second ring stacking unit 420B can be rotated so that arm 414E of
the second ring stacking unit aligns with arm 414A3 of the first
ring stacking unit 420A, or moves the distance between length of
two arms. In such example, both the arms and the weld line are
moved approximately 10 degrees. In other examples, where the arms
are spaced greater than or less than 5 degrees apart from one
another, the second ring stacking unit 420B can be rotated any
amount that will allow for alignment of the arms of the second ring
stacking unit 420B with the first ring stacking unit 420A.
[0061] The rotation may also prevent interference between two or
more gate tabs of different ring stacking units. For instance,
rotation of the second ring stacking unit 420B can also cause the
gate tabs of the second ring stacking unit to be offset relative to
the gate tabs of the first stacking units. As shown, gate tab 460A
of the first ring stacking unit 420A is offset relative to gate tab
450A of the second ring stacking unit 420B. Similarly, gate tabs
450B, 450C, and 450D will each be offset relative to the directly
adjacent gate tabs 440B, 440C, and 440D of the first ring stacking
unit 420A. The gate tabs of the first ring stacking unit 420A can
also be offset relative to the gate tabs of the second ring
stacking unit 420B by a distance W2. Since the gate tabs are fixed,
the gate tabs can move a distance W2 and be offset from the first
gate tab 450A of the first ring stacking unit by an amount W2 that
is equal to W1.
[0062] FIG. 10 provides an example of another stage of assembly
where the third ring stacking unit 420C is stacked on top of the
first and second ring stacking units 420A, 420B. As shown, the
second ring stacking unit 420B has been stacked on top of the first
ring stacking unit 420A. The gate tabs 460A-460D of the second ring
stacking unit 420B are offset relative to the weld lines 448A-448D
of the first ring stacking unit 420A. Gate tabs 460A-460D of the
second ring stacking unit 420B are also offset relative to the gate
tabs 450A-450D of the first ring stacking unit 420A. The third ring
stacking unit 420C can be rotated relative to the directly adjacent
second ring stacking unit 420B. As with regard to the stacking of
the first and second ring stacking units 420A, 420B, the third ring
stacking unit 420C may be rotated relative to the second rings
stacking unit 420B so that the weld lines 462A-D of the third ring
stacking unit 420C do not align with the weld lines 458A-458D of
the directly adjacent ring stacking unit, which is the second ring
stacking unit 420B. Additionally, the gate tabs 464A-464D of the
third ring stacking unit 420C can be offset relative to the gate
tabs 454A-D of the directly adjacent second ring stacking unit
420B, as well as the gate tabs 450A-D of the first ring stacking
unit 420A.
[0063] During the assembly process, the gate tabs can provide a
visual representation that the weld lines, which are positioned
half way between each of the gate tabs, are offset relative to one
another, as shown in FIGS. 11 and 12. Since the gate tabs are
adjacent each of the weld lines, a visual inspection of the
arrangement of the gate tabs can ensure that the weld lines are
offset from one another and evenly staggered or distributed around
the central opening. This is because in this example, the weld
lines of a particular ring stacking unit are positioned at a fixed
distance approximately 45 degrees away from each of the gate tabs
of the particular ring stacking unit. This can allow for quick and
easy assembly of the laminated load ring. However, numerous other
methods and procedures for positioning directly adjacent ring
stacking units can be implemented so that the weld lines of a ring
stacking unit do not align with the weld lines of the directly
adjacent ring stacking unit.
[0064] Any number of additional ring stacking units may be added to
form a fully assembled load ring. Assembly of a laminated load ring
can be completed when the desired number of ring stacking units
have been stacked together and any processing required to complete
the load ring is concluded. For example, eight ring stacking units
can be assembled together to form the laminated load ring 412 of
FIG. 4. Until assembly and processing of the laminated load ring is
completed, interim in-process units can be formed. As shown, for
example in FIGS. 11-12, an in-process unit 500 includes the eight
rings stacking units 420A, 420B, 420C, 420D, 420E, 420F, 420G, and
420H stacked one on top of another. As noted above, gate tabs for
each of the individual load rings are shown evenly spaced around
the ring, which visually indicates to a user that the weld lines
are also evenly spaced around the ring.
[0065] As noted above, in some cases, once the ring staking units
are stacked, the gate tabs can be removed. For instance, the gate
tabs of the in-process unit 500 and particularly the gate tabs of
each of the ring stacking units 420A-420H can be removed to form
the completed and laminated load ring 410. Additional finishing
procedures can be further completed, such as sanding the edges of
the ring stacking units 420 to form a smooth edges, removing excess
adhesive, and the like. As previously noted, in other examples, the
in-process unit may not include gate tabs, and may simply include
an interim unit that includes two or more stacked ring stacking
units. Similarly, the in-process unit may include two or more
stacked ring stacking units that include the same or different
features and that are in a stage of assembly prior to the
completion of the finished load ring.
[0066] The individual ring stacking units that form the laminated
load ring may be secured together by various types of bonding. The
bonding may occur during assembly, after assembly, or both. For
example, during assembly, an adhesive layer may be provided between
each adjacent ring stacking unit 420. In this regard, an adhesive
material may be applied to the bottom surface of a ring stacking
unit 420 and the top surface of a directly adjacent ring stacking
unit 420 to form the adhesive layer, or alternatively a top surface
and bottom surface of respective two adjacent ring stacking units
420 to form the adhesive layer. Alternatively or additionally,
ultrasonic welding or other means of bonding may be used during
assembly, as well as after assembly of the ring stacking units 420
into the laminated load ring.
[0067] Once the finishing procedures are completed, the load ring
is completed. For instance, the completion of the finishing
procedures, such as removal of the gates from each of the ring
stacking units 420A-420I, polishing edges of the individual ring
stacking units 420A-420I, and any other finishing procedures are
completed, may result in the load ring 412 of FIG. 4. As shown in
FIG. 4, the load ring includes the finished ring stacking units
420A'-420I', which are substantially similar to the ring stacking
units 420A-420I, except the ring stacking units 420A-420I have been
further processed to form the completed load ring 410. For example,
the respective gates of the ring stacking units 420A-420I have been
removed. As the weld lines of each of the ring stacking units
420A-420H have been offset relative to one another, only one weld
line, if at all, will appear along a cross section of the laminated
load ring 412. For example, as shown in the cross-sectional view of
FIG. 13, taken along line A-A of FIG. 4, only one weld line 480 of
ring stacking unit 420G appears in a cross-section, due to the
rotation of the directly adjacent ring stacking units 420A-420L
which in turn offsets the weld lines of each directly adjacent ring
stacking unit.
[0068] The load ring 410 can provide for an increased
circumferential strength. For example, if an individual ring
stacking unit fails at a hoop (circumferential) loading of 2400N
and if an eight ring assembly is formed without offsetting the weak
points, the eight ring assembly fails at a hoop loading of 19200N
or eight times 2400N. The laminated load ring can carry a greater
load, however, when the weak points are offset. In some examples,
the load can be greater than the sum total of the strength of each
individual stacking ring, and in some examples may be three times
greater than the sum total of the strength of the individual
stacking rings. In this example, the hoop strength can be at least
up to 57,600 N (or three times 19,200 N).
[0069] To better aid in understanding an example of some of the
aspects described above, reference is now made to example flow
diagram 600 of FIG. 14. As previously discussed, the following
operations do not have to be performed in the precise order
described below. Rather, as mentioned above, various operations can
be handled in a different order or simultaneously, and operations
may be added or omitted.
[0070] In block 610, a plurality of ring stacking units may be
provided. Each of the ring stacking units may be substantially
similar in shape and size. Each of the ring stacking units may
further include a main body having an opening, an interior edge
extending around the opening, a plurality of arms extending around
an exterior edge of the ring stacking unit, and a weld line in the
main body of the ring stacking unit.
[0071] In block 620, a second ring stacking unit of the plurality
of ring stacking units may be stacked on top of a first ring
stacking unit of the plurality of ring stacking units.
[0072] In block 630, the second ring stacking unit may be arranged
so that the weld line of the second ring stacking unit is offset
relative to the first ring stacking of the first ring stacking unit
in a direction extending around a circumference of the first ring
stacking unit.
[0073] All ranges recited herein include the endpoints, including
those that recite a range "between" two values. Terms such as
"about," "generally," "substantially," and the like are to be
construed as modifying a term or value such that it is not an
absolute, but does not read on the prior art. Such terms will be
defined by the circumstances and the terms that they modify as
those terms are understood by those of skill in the art. This
includes, at very least, the degree of expected experimental error,
technique error and instrument error for a given technique used to
measure a value.
[0074] It should be further understood that a description in range
format is merely for convenience and brevity and should not be
construed as an inflexible limitation on the scope of the
invention. Accordingly, the description of a range should be
considered to have specifically disclosed all the possible
sub-ranges as well as individual numerical values within that
range. For example, description of a range such as from 1 to 6
should be considered to have specifically disclosed sub-ranges such
as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6,
from 3 to 6 etc., as well as individual numbers within that range,
for example, 1, 2, 2.3, 3, 4, 5, 5.7 and 6. This applies regardless
of the breadth of the range.
[0075] Most of the foregoing alternative examples are not mutually
exclusive, but may be implemented in various combinations to
achieve unique advantages. As these and other variations and
combinations of the features discussed above can be utilized
without departing from the subject matter defined by the claims,
the foregoing description of the embodiments should be taken by way
of illustration rather than by way of limitation of the subject
matter defined by the claims. In addition, the provision of the
examples described herein, as well as clauses phrased as "such as,"
"including" and the like, should not be interpreted as limiting the
subject matter of the claims to the specific examples; rather, the
examples are intended to illustrate only one of many possible
embodiments. Further, the same or similar reference numbers in
different drawings can identify the same or similar elements.
* * * * *