U.S. patent application number 17/722537 was filed with the patent office on 2022-07-28 for autonomous roof bolter and related methods.
The applicant listed for this patent is J.H. FLETCHER & CO.. Invention is credited to Robert D. Burgess, Timothy D. Burgess, William A. Burgess, William Garnet Kendall.
Application Number | 20220235660 17/722537 |
Document ID | / |
Family ID | |
Filed Date | 2022-07-28 |
United States Patent
Application |
20220235660 |
Kind Code |
A1 |
Kendall; William Garnet ; et
al. |
July 28, 2022 |
AUTONOMOUS ROOF BOLTER AND RELATED METHODS
Abstract
An autonomous roof bolter includes a material handling system
having a storage pod with a plurality of spaced, fixed holders,
each receiving at least one of a plurality of roof bolts. A
guidance system may automatically guide the roof bolter to a
location for installing a roof bolt, such as by using a manipulator
for retrieving the roof bolt from the storage pod and delivering it
to a drill mast. The guidance provided by the guidance system may
be distance or direction. Related methods are disclosed.
Inventors: |
Kendall; William Garnet;
(Chesapeake, OH) ; Burgess; Timothy D.; (South
Point, OH) ; Burgess; Robert D.; (Huntington, WV)
; Burgess; William A.; (Huntington, WV) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
J.H. FLETCHER & CO. |
Huntington |
WV |
US |
|
|
Appl. No.: |
17/722537 |
Filed: |
April 18, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16639437 |
Feb 14, 2020 |
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PCT/US2018/048273 |
Aug 28, 2018 |
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17722537 |
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62550900 |
Aug 28, 2017 |
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International
Class: |
E21D 20/00 20060101
E21D020/00; G05D 1/02 20060101 G05D001/02 |
Claims
1. A machine for traversing a mine passage and installing at least
one roof bolt therein, comprising: a bolt holder for holding the at
least one roof bolt; a drill mast for installing the at least one
roof bolt in the mine passage; and a guidance system for
automatically guiding the machine to a location for installing the
at least one roof bolt.
2. The machine of claim 1, wherein the guidance system comprises a
laser mounted at a fixed location in the mine passage and a
reflective target mounted on the machine in a path of the laser,
whereby a position of the laser on the target may be used to
control alignment of the machine within the mine passage.
3. The machine of claim 2, further including a camera for capturing
the position of the laser.
4. The machine of claim 2, wherein the reflective target is mounted
on a gimbal.
5. The machine of claim 2 further including a transparent or
translucent target placed in series with the reflective target.
6. The machine of claim 1, wherein the guidance system comprises a
distance sensor including a laser, a sensor, and a reflective
target in a path of the laser.
7. The machine of claim 6, wherein the distance sensor is mounted
on a gimbal.
8. The machine of claim 6, wherein the bolt holder comprises a
storage pod for holding a plurality of roof bolts, and a
manipulator for individually feeding the roof bolts from the
storage pod for installation.
9. The machine of claim 6, wherein the bolt holder comprises a
carousel for holding a plurality of roof bolts.
Description
[0001] This application is a divisional of U.S. application Ser.
No. 16/639,437 filed on Feb. 14, 2020, which is a U.S. National
Stage of PCT/US2018/048273 filed on Aug. 28, 2018, which claims
priority to U.S. Provisional Patent Application Ser. No.
62/550,900, filed Aug. 28, 2017, the disclosures of which are
incorporated herein by reference.
TECHNICAL FIELD
[0002] This application relates to the underground mining arts and,
in particular, to a roof bolter that may operate at least partly,
and potentially fully, in an autonomous manner.
BACKGROUND
[0003] In underground mining, roof bolters are commonly used to
drill holes into the roof and install roof bolts to support the
roof. The majority of roof bolters in underground mines are
manually operated. Specifically, an operator manually places a
drill steel into a dedicated drill head, drills the hole by
operating manual controls, and then removes the drill steel. Next,
a bolt inserter (wrench) is typically placed in the drill head, and
a roof bolt is placed in the bolt inserter. The operator then
installs the bolt by operating manual controls. This process is
very labor intensive and relies heavily on the operator's judgment
as to where to install roof bolts.
[0004] Where space and other parameters allow, remotely controlled
roof bolters are used. These machines typically have a dedicated
drill module with dedicated drill steel, a dedicated bolt module
with a dedicated bolt wrench, and a bolt storage carousel.
Typically, bolt carousels are limited to storing a maximum of
approximately 16 bolts simply due to the size of the carousel.
[0005] To operate the machine, the operator first manually places
bolts into the bolt carousel. The bolts are held in place with some
type of retaining mechanism, which can require a significant amount
of force for the operator to overcome. Wear and tear of the
retainers can result in bolts falling out of the carousel during
machine operation. The operator then enters a remote operating area
on the machine, frequently a fully enclosed cab. The operator can
now safely tram the machine, position the drill and bolt modules,
drill holes and insert bolts. After the bolts in the carousel are
used, the machine must be moved back to a safe area and additional
bolts placed in the carousels.
[0006] Mine engineers design a specific roof control plan which
determines the type, size, length, and location of each roof bolt.
It is critical that the holes be drilled in the locations specified
by the engineer. In addition, roof bolts are used to suspend items
such as belt conveyor structure from the roof Proper operation of
the belt conveyor is dependent upon the bolts being installed in
precise locations to help ensure proper alignment.
[0007] Typically, the location of where to drill holes and install
bolts is estimated visually by the operator. This results in
significant variance in bolt placement. Even if a tape measure or
similar device is used there will be relatively large tolerances on
each specific bolt installed. These tolerances will be compounded
as more and more rows of bolts are installed.
[0008] A fully autonomous machine, with proper guidance and
positioning systems, along with the ability to store and manipulate
a large number of roof bolts, would significantly improve safety,
efficiency, and accuracy of the bolt installation process.
Furthermore, a system which would reduce operator effort to place
the bolts in the storage device, which would hold a larger number
of bolts, reduce the possibility of bolts falling out of the
storage device, and allow for automation of bolt movement from the
storage device to the bolt module, would be a significant
improvement in safety and efficiency. A more accurate and simple
method of accurately positioning the roof bolting machine would
allow for more accurate bolt installation and also allow for
automation of the machine positioning.
SUMMARY
[0009] According to one aspect of the disclosure, a material
handling system for a roof bolter comprises a plurality of roof
bolts. A storage pod includes a plurality of spaced, fixed holders,
each spaced, fixed holder receiving at least one of the plurality
of roof bolts.
[0010] In one embodiment, the system further includes a manipulator
for retrieving individual roof bolts from the storage pod for
installation. The storage pod may comprise a box for at least
partially receiving a portion of each of the plurality of roof
bolts. The box may be adapted to be lifted by a lifter.
[0011] The plurality of fixed holders may be arranged in a grid.
The grid may comprise first and second rows of fixed holders. The
first and second rows may be generally parallel, or generally
perpendicular. Each of the plurality of fixed holders comprises
aligned openings formed in spaced plates, and may hold between
16-300 roof bolts.
[0012] According to a further aspect of the disclosure, a machine
for traversing a mine passage and installing at least one roof bolt
therein is provided. The machine comprises a bolt holder for
holding the at least one roof bolt, and a drill mast for installing
the at least one roof bolt in the mine passage. A guidance system
is provided for automatically guiding the machine to a location for
installing the at least one roof bolt.
[0013] In one embodiment, the guidance system comprises a laser
mounted at a fixed location in the mine passage and a reflective
target mounted on the machine in a path of the laser, whereby a
position of the laser on the target may be used to control
alignment of the machine within the mine passage. A camera may be
provided for capturing the position of the laser on the target,
which position may be used for guiding movement of the roof bolter.
The reflective target may be mounted on a gimbal to ensure
verticality, and a transparent or translucent target may be placed
in series with the reflective target.
[0014] In this or another embodiment, the guidance system may
comprise a distance sensor including a laser, a sensor, and a
reflective target in a path of the laser. The arrangement is such
that a time of flight may be determined in order to guide movement
of the roof bolter in a forward direction. The distance sensor may
be mounted on a gimbal.
[0015] The bolt holder may comprise a storage pod for holding a
plurality of roof bolts, and a manipulator for individually feeding
the roof bolts from the storage pod for installation.
Alternatively, the bolt holder may comprise a carousel for holding
a plurality of roof bolts.
[0016] According to a further aspect of the disclosure, a method
for installing a roof bolt in a mine passage using a roof bolter is
provided. The method comprises withdrawing the roof bolt axially
from a holder associated with a bolter, the holder preventing
side-to-side movement of the roof bolt. The method further
comprises installing the roof bolt in a borehole formed in the mine
passage.
[0017] Yet a further aspect of the disclosure pertains to a method
for installing roof bolts in a mine passage using a roof bolter.
The method comprises (a) using a laser-based system, determining a
heading or a travel distance of the roof bolter to reach a first
position within the mine passage; and (b) installing a roof bolt at
the first position. The method may further comprise repeating steps
(a) and (b) for a second position.
[0018] In one embodiment, the installing step comprises retrieving
the roof bolt from a fixed holder and then using a drill mast to
install the roof bolt in a borehole in the mine passage at the
first position. The installing step may comprise retrieving the
roof bolt from a carousel and then using a drill mast to install
the roof bolt in a borehole in the mine passage at the first
position.
[0019] Still another aspect of the disclosure pertains to a method
for installing roof bolts in a mine passage using a roof bolter.
The method comprises guiding the roof bolter for movement within
the mine passage via a laser-based guidance system for installing a
plurality of roof bolts in an aligned row along the passage. The
guiding step may comprise mounting a laser at a fixed location in
the mine passage, mounting a reflective target mounted on the roof
bolter in a path of the laser, and using a position of the laser on
the target to control the alignment of the roof bolter within the
mine passage. The method may further include the step of placing a
transparent or translucent target placed in series with the
reflective target. The guiding step may comprise projecting a laser
onto a reflective target and using a sensor to determine the time
of flight in order to guide the advance of the roof bolter within
the mine passage.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0020] The accompanying drawing figures incorporated herein and
forming a part of the specification, illustrate several aspects of
the disclosed inventions and, together with the description, serve
to explain certain principles thereof. In the drawing figures:
[0021] FIG. 1 is a side view of a mine machine, such as a roof
bolter;
[0022] FIG. 2 is an end view of the mine machine;
[0023] FIG. 3 is a perspective view of the mine machine;
[0024] FIG. 4 is an enlarged perspective view of a portion of the
mining machine including a storage pod for receiving roof bolts and
a manipulator for delivering the bolts to a drill mast for
installation; and
[0025] FIGS. 5, 6, 7 are various views of one embodiment of the
storage pod;
[0026] FIG. 8 is a schematic view of one embodiment of a guidance
system for a mine machine, such as a roof bolter;
[0027] FIG. 9 illustrates targets used in the system of FIG. 8;
[0028] FIG. 10 is another embodiment of a guidance system for a
mine machine; and
[0029] FIG. 11 illustrates an example of a drill mast associated
with a rotary carousel for holding roof bolts.
[0030] Reference will now be made in detail to the present
preferred embodiments of the disclosed inventions, examples of
which are illustrated in the accompanying drawing figures.
DETAILED DESCRIPTION
[0031] With reference to FIGS. 1-11, an at least partially
autonomous roof bolter 10 is disclosed that may resolve some or all
of the foregoing concerns, and possibly others that have yet to be
realized. As can be understood from FIGS. 1-3, the bolter 10 may
comprise a mobile vehicle V including ground-engaging structures,
such as wheels W, for traversing about a mine passage P and
installing roof bolts T into corresponding surfaces thereof, such
as the roof R, as is outlined further in the following description.
Despite the use of the term "roof" bolts, it will be understood by
skilled artisans that this is meant to include and cover the
installation of anchors in any surface of the mine passage,
including the ribs I.
[0032] According to one aspect of the improved bolter 10, a pod 12
for handling and temporarily storing bolts T is provided. As
perhaps best understood from FIGS. 5, 6, and 7, the storage pod 12
comprises a box 12a with fixed, spaced apart holders 14, each for
at least partially receiving the specific roof bolt T (which may of
course vary in size, shape, or functionality depending on the
particular application). The holders 14 may be formed by upper and
lower retainers, such as plates 14a, 14b having aligned openings.
The aligned openings thus form receivers for receiving and holding
the bolts T in a vertical orientation in the illustrated
embodiment. The holders 14 may be designed such that the roof bolt
T can simply be dropped into place (such as from above), and the
corresponding holder automatically orients the bolt and holds it in
an accurate location for retrieval (e.g., with an upper, grippable
portion of the bolt T extending above the upper periphery of the
box 12a).
[0033] The pod 12 may be pre-loaded on the surface of the mine or
at a remote bolt storage location. As perhaps best understood from
reviewing FIGS. 4-8, the box 12a may be designed such that it can
be handled with a lifter, such as a forklift, and placed onto the
vehicle V of bolter 10. The box 12a may be fabricated of metal, and
may be generally rectangular in cross-sectional shape or plan view,
but other shapes could be used as well. In a typical application,
the pod 12 can be designed to hold from about 16 to about 300 bolts
(with a preference for one bolt T in each holder 14).
[0034] As indicated in FIG. 4, a bolt manipulator, such as a
multi-axis robotic arm 18 with a gripper 18a, may be mounted to the
vehicle V in proximity to the bolt storage pod 12. An onboard
controller or computer C may be provided to direct the robotic arm
18 to retrieve a specific bolt T from a corresponding holder 14
(which bolt may be unrestrained for movement in an axial direction
(e.g., vertically in the illustrated embodiment), but held against
side-to-side movement laterally) and deliver it to the bolting
module 24. This module 24 may comprise an extendable mast 26
including a drill 26a for drilling a borehole in a surface of the
mine passage P, and also for guiding the bolt T into the borehole
once formed (but separate masts and drills could be used for these
purposes). This sequence could be triggered by a human, or the
bolter 10 may automatically trigger the process using sensors.
[0035] As can be appreciated, the layout of the holders 14 of the
storage pod 12 may be such that the roof bolts T are arranged in a
grid. That is, a plurality of roof bolts T located in a first
aligned row X extend in a first direction D1, and a plurality of
roof bolts located in a second aligned row Y extend in a second
direction D2 that is generally perpendicular to the first
direction, with at least one roof bolt being common to each row. As
can be appreciated, a plurality of generally parallel rows may
result when this pattern is expanded to include multiple rows in
each direction. In any case, from the resulting grid thus formed,
the manipulator (e.g., arm 18) may be reliably guided to a
particular location for retrieving a selected roof bolt T (such as
by gripping the upper exposed portion) for delivery to the bolting
module 24. As indicated, the arrangement may be such that more than
sixteen bolts, but fewer than about three hundred, are provided in
a single pod 12.
[0036] A further aspect of the disclosure pertains to a guidance
system 30 providing a simple and accurate method of determining if
a machine, such as bolter 10, is parallel to a desired heading and
accurately positioned with respect to the sides of the mine passage
P. In one embodiment, as illustrated in FIG. 8, the system 30
includes a single point type laser generator 32 for projecting a
laser beam B in a travel direction. The laser 32 may be hung from
the roof R of the mine passage P at a known survey location and
aligned parallel with a direction of travel within the passage. A
reflective target 34 is mounted onto the roof bolter 10 (or other
machine). The target 34 may be mounted on a gimbal 36 to maintain
verticality, even though the bolter 10 may undulate due to uneven
floor conditions.
[0037] With reference to FIGS. 8 and 9, a second, translucent or
transparent (e.g., clear) target 38 may be placed in series with
the reflective target 34. Although the second target 38 allows the
beam B to pass, it will still show some reflection. Consequently,
the operator now has two target points forming a line, which may
insure that the bolter 10 is travelling in a manner that is
generally aligned with (e.g., parallel to) a travel direction of
the mine passage P.
[0038] For manual movement of the bolter 10, the operator can
simply look at the target and steer accordingly to keep the laser
dot D in the center of the target 34, which may be determined using
an alignment marking M. For automated control, a camera, such as a
video camera 39, may be mounted to the bolter 10 or machine to
replace the need for the operator to look at the target 34. The
video camera 39 may feed captured video to a computer with video
capture software that identifies the exact location of the laser
dot D on the reflective target 34. If the dot moves from the center
of the target 34 (as indicated by the marking M), an onboard
controller or computer C for controlling the direction of travel of
the bolter 10 may issue a suitable turn command to a steering
control module S to correct the position of the bolter.
[0039] According to a further aspect of the disclosure, a distance
sensor system 40 may also be employed to provide a simple and
accurate method of determining the correct distance of the roof
bolter 10 or other machine from a specific point. A reflective
target 42 is hung from the roof R of the mine passage P at a known
survey location and aligned generally parallel with the entry. A
retro-reflective laser distance sensor 44 (e.g., a "time of flight"
sensor) is mounted onto the roof bolter 10. The laser distance
sensor 44 is mounted on a gimbal 46 to insure verticality, even
though the bolter 10 may undulate due to uneven floor
conditions.
[0040] In use, the laser sensor 44 sends a laser beam B out to the
reflective target 42, which reflects it back to the sensor (beam
B'). The time of flight for the beam B, B' is measured allowing the
sensor 44 to calculate the distance to the reflective target 42
very accurately. The actual distance from the target 42 may then be
displayed on a computer screen (not shown) for the operator. For
manual movement of the bolter 10, the operator can simply look at
the screen and tram the bolter until the correct distance is
reached.
[0041] For automated control, the sensed distance from the target
42 may be fed into a controller or computer C. When a tram command
is initiated (either by an operator or automatically), the computer
C will continuously monitor the location of the bolter 10. As the
bolter 10 approaches the desired location, the computer C may issue
control commands to a drive and steering module M to begin slowing
down the forward movement at a controlled rate and then stopping it
at a precise location for placement of a roof bolt.
[0042] The system 40 thus provides a simple and accurate method of
determining the accurate distance of the roof bolter 10 from a
specific point. In addition, a scanning laser can be used to
generate a map of a heading using collected data. Together, these
guidance systems 30, 40 can provide accurate machine positioning
and, in the case of a bolter 10, help to ensure that the bolts are
installed in a straight line having the correct spacing, without
relying on operator guesswork and the resulting potential for
error.
[0043] As can be appreciated, the proposed concepts may utilize a
building block approach to provide a machine or bolter 10 which can
be fully autonomous, including in connection with the pod 12 and
manipulator (e.g., arm 18). The bolter 10 may also utilize
dedicated drill and bolt modules 24 associated with the mast 26
(with drill 26a), which can accept either bolt carousels 28 with a
relatively smaller number of roof bolts (e.g., less than 30), or
the carousels can be removed and replaced with the bolt storage pod
12 and a robotic bolt manipulator (e.g. arm 18). Further details
may be found in one or more of U.S. Patent Application Publication
Nos. 2007/0283614 and 2006/0283614.
[0044] Each of the following terms written in singular grammatical
form: "a", "an", and the", as used herein, means "at least one", or
"one or more". Use of the phrase One or more" herein does not alter
this intended meaning of "a", "an", or "the". Accordingly, the
terms "a", "an", and "the", as used herein, may also refer to, and
encompass, a plurality of the stated entity or object, unless
otherwise specifically defined or stated herein, or, unless the
context clearly dictates otherwise. For example, the phrases: "a
unit", "a device", "an assembly", "a mechanism", "a component, "an
element", and "a step or procedure", as used herein, may also refer
to, and encompass, a plurality of units, a plurality of devices, a
plurality of assemblies, a plurality of mechanisms, a plurality of
components, a plurality of elements, and, a plurality of steps or
procedures, respectively.
[0045] Each of the following terms: "includes", "including", "has",
"having", "comprises", and "comprising", and, their
linguistic/grammatical variants, derivatives, or/and conjugates, as
used herein, means "including, but not limited to", and is to be
taken as specifying the stated components), feature(s),
characteristic{circumflex over ( )}), parameters), integers), or
step(s), and does not preclude addition of one or more additional
components), feature(s), characteristics), parameters), integer(s),
step(s), or groups thereof. Each of these terms is considered
equivalent in meaning to the phrase "consisting essentially of"
Each of the phrases "consisting of" and "consists of", as used
herein, means "including and limited to".
[0046] The phrase "consisting essentially of, as used herein, means
that the stated entity or item (system, system unit, system
sub-unit device, assembly, sub-assembly, mechanism, structure,
component element or, peripheral equipment utility, accessory, or
material, method or process, step or procedure, sub-step or
sub-procedure), which is an entirety or part of an exemplary
embodiment of the disclosed invention, or/and which is used for
implementing an exemplary embodiment of the disclosed invention,
may include at least one additional feature or characteristic"
being a system unit system sub-unit device, assembly, sub-assembly,
mechanism, structure, component or element or, peripheral equipment
utility, accessory, or material, step or procedure, sub-step or
sub-procedure), but only if each such additional feature or
characteristic" does not materially alter the basic novel and
inventive characteristics or special technical features, of the
claimed item.
[0047] The term "method", as used herein, refers to steps,
procedures, manners, means, or/and techniques, for accomplishing a
given task including, but not limited to, those steps, procedures,
manners, means, or/and techniques, either known to, or readily
developed from known steps, procedures, manners, means, or/and
techniques, by practitioners in the relevant field(s) of the
disclosed invention.
[0048] Throughout this disclosure, a numerical value of a
parameter, feature, characteristic, object or dimension, may be
stated or described in terms of a numerical range format. Such a
numerical range format, as used herein, illustrates implementation
of some exemplary embodiments of the invention, and does not
inflexibly limit the scope of the exemplary embodiments of the
invention. Accordingly, a stated or described numerical range also
refers to, and encompasses, all possible sub-ranges and individual
numerical values (where a numerical value may be expressed as a
whole, integral, or fractional number) within that stated or
described numerical range. For example, a stated or described
numerical range from 1 to 6'' also refers to, and encompasses, all
possible 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., and
individual numerical values, such as T, "1.3", "2, "2.8", "3",
"3.5", "4", "4.6", "5", "5.2", and "6", within the stated or
described numerical range of from 1 to 6''. This applies regardless
of the numerical breadth, extent or size, of the stated numerical
range.
[0049] Moreover, for stating or describing a numerical range, the
phrase "in a range of between about a first numerical value and
about a second numerical value", is considered equivalent to, and
meaning the same as, the phrase "in a range of from about a first
numerical value to about a second numerical value", and, thus, the
two equivalents meaning phrases may be used interchangeably. For
example, for stating or describing the numerical range of room
temperature, the phrase "room temperature refers to a temperature
in a range of between about 20.degree. C. and about 25.degree. C.,"
and is considered equivalent to, and meaning the same as, the
phrase "room temperature refers to a temperature in a range of from
about 20.degree. C. to about 25.degree. C."
[0050] Terms of approximation, such as the terms about,
substantially, approximately, etc., as used herein, refers to
.+-.10% of the stated numerical value.
[0051] The phrase "operatively connected", as used herein,
equivalency refers to the corresponding synonymous phrases
"operatively joined", and "operatively attached," where the
operative connection, operative joint or operative attachment, is
according to a physical, or/and electrical, or/and electronic,
or/and mechanical, or/and electro-mechanical, manner or nature,
involving various types and kinds of hardware or/and software
equipment and components.
[0052] It is to be fully understood that certain aspects,
characteristics, and features, of the invention, which are, for
clarity, illustratively described and presented in the context or
format of a plurality of separate embodiments, may also be
illustratively described and presented in any suitable combination
or sub-combination in the context or format of a single embodiment.
Conversely, various aspects, characteristics, and features, of the
invention which are illustratively described and presented in
combination or sub-combination in the context or format of a single
embodiment may also be illustratively described and presented in
the context or format of a plurality of separate embodiments.
[0053] Although the invention has been illustratively described and
presented by way of specific exemplary embodiments, and examples
thereof, it is evident that many alternatives, modifications,
or/and variations, thereof, will be apparent to those skilled in
the art. Accordingly, it is intended that all such alternatives,
modifications, or/and variations, fall within the spirit of, and
are encompassed by, the broad scope of the appended claims.
[0054] All publications, patents, and or/and patent applications,
cited or referred to in this disclosure are herein incorporated in
their entirety by reference into the specification, to the same
extent as if each individual publication, patent, or/and patent
application, was specifically and individually indicated to be
incorporated herein by reference. In addition, citation or
identification of any reference in this specification shall not be
construed or understood as an admission that such reference
represents or corresponds to prior art of the present invention. To
the extent that section headings are used, they should not be
construed as necessarily limiting.
* * * * *