U.S. patent application number 16/115327 was filed with the patent office on 2019-04-04 for automatic tire loader/unloader for stacking/unstacking tires in a trailer.
The applicant listed for this patent is Daifuku Co., Ltd., Wynright Corporation. Invention is credited to Tim Criswell.
Application Number | 20190100390 16/115327 |
Document ID | / |
Family ID | 51165261 |
Filed Date | 2019-04-04 |
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United States Patent
Application |
20190100390 |
Kind Code |
A1 |
Criswell; Tim |
April 4, 2019 |
Automatic Tire Loader/Unloader for Stacking/Unstacking Tires in a
Trailer
Abstract
An automatic tire loader/unloader for stacking/unstacking tires
in a trailer is disclosed. In one embodiment, a mobile base
structure provides a support framework for a drive subassembly,
conveyance subassembly, an industrial robot, a distance measurement
subassembly, and a control subassembly. Under the operation of the
control subassembly, tires advance through a powered transportation
path to an industrial robot which places the tires within the
trailer in a vertical stacking pattern or a rick-stacking pattern,
for example. The control subassembly coordinates the selective
articulated movement of the industrial robot and the activation of
the drive subassembly based upon the distance measurement
subassembly detecting objects, including tires, within a detection
space, dimensions of the trailer provided to the control
subassembly, and dimensions of the tires provided to the control
subassembly.
Inventors: |
Criswell; Tim; (Arlington,
TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Wynright Corporation
Daifuku Co., Ltd. |
Elk Grove
Osaka |
IL |
US
JP |
|
|
Family ID: |
51165261 |
Appl. No.: |
16/115327 |
Filed: |
August 28, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
15850887 |
Dec 21, 2017 |
10059537 |
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16115327 |
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15646348 |
Jul 11, 2017 |
9850081 |
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15850887 |
|
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|
15263849 |
Sep 13, 2016 |
9701491 |
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15646348 |
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14156399 |
Jan 15, 2014 |
9440349 |
|
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15263849 |
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61752714 |
Jan 15, 2013 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B65G 61/00 20130101;
B65G 21/14 20130101; B65G 67/08 20130101; B65G 67/02 20130101; B25J
5/007 20130101; B25J 5/005 20130101; B65G 57/20 20130101; B65G
2201/0273 20130101; B25J 15/00 20130101 |
International
Class: |
B65G 67/02 20060101
B65G067/02; B65G 61/00 20060101 B65G061/00; B65G 21/14 20060101
B65G021/14; B25J 5/00 20060101 B25J005/00; B25J 15/00 20060101
B25J015/00; B65G 67/08 20060101 B65G067/08; B65G 57/20 20060101
B65G057/20 |
Claims
1. A method for stacking tires within a trailer parked at a loading
bay, the method comprising: providing an automatic tire
loader/unloader including a base structure having an industrial
robot mounted thereto, the industrial robot is operable to handle
tires; and executing at the automatic tire loader/unloader a
rick-rack stacking routine including processor-executable
instructions to: specify a search operation to identify a tire
skyline including an active quadrant, specify a search operation to
identify a hole and hump of an adjacent tire pair within the active
quadrant, specify a search operation to identify the sequential
tire placement direction, and calculate instructions for executing
a rick-rack stacking pattern of tires.
2. The method as recited in claim 1, further comprising connecting
a conveyance subassembly disposed on the mobile base to a
telescoping conveyor unit having a supply of tires associated
therewith.
3. The method as recited in claim 1, further comprising driving the
automatic tire loader/unloader into the trailer.
4. The method as recited in claim 1, further comprising detecting
the location of the automatic tire loader/unloader within the
trailer with a distance measurement subassembly disposed on the
mobile base structure.
5. The method as recited in claim 4, further comprising stopping,
in response to distance measurement data from the distance
measurement subassembly, the automatic tire loader/unloader
proximate to the front wall of the trailer.
6. The method as recited in claim 1, further comprising presenting
a stream of tires to an industrial robot disposed on the base
structure, the industrial robot providing selective articulated
movement through a reachable space such that the industrial robot
is operable to place the tires within the trailer.
7. The method as recited in claim 1, further comprising
sequentially loading the tires within the trailer with the
industrial robot according to the rick-rack stacking routine
designed to optimize the use of available space within the
trailer.
8. The method as recited in claim 1, further comprising
interrupting the loading of tires in response to detection by the
distance measurement subassembly of presence of tires within the
reachable space.
9. The method as recited in claim 8, further comprising reversing
and repositioning the automatic tire loader/unloader to refresh the
reachable space.
10. The method as recited in claim 9, further comprising resuming
the sequential loading of the tires.
11. A method for stacking tires within a trailer parked at a
loading bay, the method comprising: providing an automatic tire
loader/unloader including a base structure having an industrial
robot mounted thereto, the industrial robot is operable to handle
tires; and executing at the automatic tire loader/unloader a
rick-rack unstacking routine including processor-executable
instructions to: specify a search operation to identify a tire
skyline including an active quadrant, specify a search operation to
identify a hole and hump of an adjacent tire pair within the active
quadrant, specify a search operation to identify the sequential
tire placement direction, and calculate instructions for executing
a rick-rack unstacking pattern of tires.
12. The method as recited in claim 11, further comprising
connecting a conveyance subassembly disposed on the mobile base to
a telescoping conveyor unit to receive a supply of tires.
13. The method as recited in claim 11, further comprising driving
the automatic tire loader/unloader into the trailer.
14. The method as recited in claim 11, further comprising detecting
the location of the automatic tire loader/unloader within the
trailer with a distance measurement subassembly disposed on the
mobile base structure.
15. The method as recited in claim 14, further comprising stopping,
in response to distance measurement data from the distance
measurement subassembly, the automatic tire loader/unloader
proximate to the front wall of the trailer.
16. The method as recited in claim 11, further comprising
presenting a stream of tires to a conveyance subassembly disposed
on the base structure, the industrial robot providing selective
articulated movement through a reachable space such that the
industrial robot is operable to remove the tires from the
trailer.
17. The method as recited in claim 11, further comprising
sequentially unloading the tires within the trailer with the
industrial robot according to the rick-rack unstacking routine.
18. The method as recited in claim 11, further comprising
interrupting the unloading of tires in response to detection by the
distance measurement subassembly of absence of tires within the
reachable space.
19. The method as recited in claim 18, further comprising
forwarding and repositioning the automatic tire loader/unloader to
refresh the reachable space.
20. The method as recited in claim 19, further comprising resuming
the sequential unloading of the tires.
Description
PRIORITY STATEMENT & CROSS-REFERENCE TO RELATED
APPLICATIONS
[0001] This application is a continuation of co-pending U.S. patent
application Ser. No. 15/850,887, entitled "Automatic Tire
Loader/Unloader for Stacking/Unstacking Tires in a Trailer," filed
on Dec. 21, 2017, in the name of Tim Criswell, now U.S. Pat. No.
10,059,537, and issued on Aug. 28, 2018; which is a continuation of
U.S. patent application Ser. No. 15/646,348, entitled "Automatic
Tire Loader/Unloader for Stacking/Unstacking Tires in a Trailer,"
filed on Jul. 11, 2017, in the name of Tim Criswell, now U.S. Pat.
No. 9,850,081, and issued on Dec. 26, 2017; which is a continuation
of U.S. patent application Ser. No. 15/263,849, entitled "Automatic
Tire Loader/Unloader for Stacking/Unstacking Tires in a Trailer,"
filed on Sep. 13, 2016, in the name of Tim Criswell, now U.S. Pat.
No. 9,701,491, and issued on Jul. 11, 2017; which is a continuation
of U.S. patent application Ser. No. 14/156,399, entitled "Automatic
Tire Loader/Unloader for Stacking/Unstacking Tires in a Trailer,"
filed on Jan. 15, 2014, in the name of Tim Criswell, now U.S. Pat.
No. 9,440,349 issued on Sep. 13, 2016; which claims priority from
U.S. Patent Application No. 61/752,714, entitled "Automatic Tire
Loader/Unloader for Stacking/Unstacking Tires in a Trailer," and
filed on Jan. 15, 2013, in the name of Tim Criswell; all of which
are hereby incorporated by reference for all purposes.
TECHNICAL FIELD OF THE INVENTION
[0002] This invention relates, in general, to a machine for
handling products and, more particularly, to a system and method
for automated truck loading and unloading which employ an automatic
tire loader/unloader designed to stack tires within a trailer or
remove tires from a trailer.
BACKGROUND OF THE INVENTION
[0003] Loading docks and loading bays are commonly found in large
commercial and industrial buildings and provide arrival and
departure points for large shipments brought to or taken away by
trucks and vans. By way of example, a truck may back into a loading
bay such that the bumpers of the loading bay contact the bumpers on
the trailer and a gap is created between the loading bay and the
truck. A dock leveler or dock plate bridges the gap between the
truck and a warehouse to provide a fixed and substantially level
surface. Power moving equipment, such as forklifts or conveyor
belts, is then utilized to transport the cargo from the warehouse
to the truck. Human labor is then employed to stack the cargo in
the truck. This is particularly true of the stacking and unstacking
of tires during the respective loading and unloading of the truck.
These systems are designed to maximize the amount the cargo loaded
while minimizing the use of human labor to both protect and extend
the life of the workforce. A need still exists, however, for
improved truck loading systems that further reduce the use of human
labor when stacking and unstacking tires as part of loading and
unloading a truck.
SUMMARY OF THE INVENTION
[0004] It would be advantageous to achieve a system and method for
automated stacking and unstacking of tires that would enable a
truck to be fully loaded and unloaded using minimal or no human
labor, thereby minimizing the time to load/unload the truck and the
need for human capital. It would also be desirable to enable a
robotic solution that would address this problem by stacking and
unstacking tires using a rick-rack pattern, which is optimal for
tire loading/unloading. To better address one or more of these
concerns, an automatic tire loader/unloader for stacking/unstacking
tires in a trailer is disclosed. In one embodiment, a mobile base
structure provides a support framework for a drive subassembly,
conveyance subassembly, an industrial robot, a distance measurement
subassembly such as a three dimensional camera system, and a
control subassembly. Under the operation of the control
subassembly, tires advance through a powered transportation path to
an industrial robot which places the tires within the trailer in a
vertical stacking pattern or a rick-stacking pattern, for example.
The control subassembly coordinates the selective articulated
movement of the industrial robot and the activation of the drive
subassembly based upon the distance measurement subassembly
detecting objects, including tires, within a detection space,
dimensions of the trailer provided to the control subassembly, and
dimensions of the tires provided to the control subassembly. These
systems and methodologies utilizing the present automatic tire
loader therefore maximize the amount the product and cargo loaded
while minimizing the use of human labor to both protect and extend
the life of the workforce. These and other aspects of the invention
will be apparent from and elucidated with reference to the
embodiments described hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] For a more complete understanding of the features and
advantages of the present invention, reference is now made to the
detailed description of the invention along with the accompanying
figures in which corresponding numerals in the different figures
refer to corresponding parts and in which:
[0006] FIG. 1 is a side elevational view with partial cross-section
of one embodiment of an automatic tire loader/unloader positioning
tires within a trailer of a truck;
[0007] FIG. 2A is a top plan view of the automatic tire loader
illustrated in FIG. 1;
[0008] FIG. 2B is a side elevation view of the automatic tire
loader illustrated in FIG. 1;
[0009] FIG. 2C is a second side elevation view of the automatic
tire loader illustrated in FIG. 1;
[0010] FIG. 2D is a front elevation view of the automatic tire
loader illustrated in FIG. 1;
[0011] FIG. 2E is a rear elevation view of the automatic tire
loader illustrated in FIG. 1;
[0012] FIG. 2F is a front perspective view of the automatic tire
loader illustrated in FIG. 1;
[0013] FIG. 2G is a rear perspective view of the automatic tire
loader illustrated in FIG. 1;
[0014] FIG. 3A is a perspective view of a portion of the automatic
tire loader of FIG. 1 and in particular a detailed view of one
embodiment of a mobile base;
[0015] FIG. 3B is a second perspective view of the mobile base
illustrated in FIG. 3A;
[0016] FIG. 4A is a perspective view of one embodiment of an end
effector, which forms a portion of the automatic tire loader, being
posited to grip a tire;
[0017] FIG. 4B is a side elevation view of the end effector in FIG.
4A;
[0018] FIG. 4C is a top plan view of the end effector in FIG.
4A;
[0019] FIG. 5A is a perspective view of one embodiment of an end
effector, which forms a portion of the automatic tire loader,
gripping a tire;
[0020] FIG. 5B is a side elevation view of the end effector in FIG.
5A;
[0021] FIG. 5C is a top plan view of the end effector in FIG.
5A;
[0022] FIGS. 6A through 6D are schematic diagrams of one
operational embodiment of the automatic tire loader of FIG. 1
stacking tires in the trailer of the truck;
[0023] FIGS. 7A through 7D are schematic diagrams of one
operational embodiment of the automatic tire loader of FIG. 1
unstacking tires in the trailer of the truck;
[0024] FIGS. 8A through 8D are top plan views of an operational
embodiment corresponding to FIGS. 6A through 6D;
[0025] FIGS. 9A through 9D are top plan views of an operational
embodiment corresponding to FIGS. 7A through 7D;
[0026] FIG. 10 is a schematic block diagram of one embodiment of
the automatic tire loader;
[0027] FIG. 11 is a schematic block diagram of one embodiment of
the automatic tire loader in additional detail;
[0028] FIG. 12 is a schematic diagram of one embodiment of a robot
controller which forms a portion of the automatic tire loader;
[0029] FIG. 13 is a schematic diagram of one embodiment of a
distance measurement subassembly which forms a component of the
automatic tire loader; and
[0030] FIG. 14 is a schematic diagram of another embodiment of a
distance measurement subassembly which forms a component of the
automatic tire loader.
DETAILED DESCRIPTION OF THE INVENTION
[0031] While the making and using of various embodiments of the
present invention are discussed in detail below, it should be
appreciated that the present invention provides many applicable
inventive concepts, which can be embodied in a wide variety of
specific contexts. The specific embodiments discussed herein are
merely illustrative of specific ways to make and use the invention,
and do not delimit the scope of the present invention.
[0032] Referring initially to FIG. 1, therein is depicted an
automatic tire loader/unloader that is schematically illustrated
and generally designated 10 and may be referred to as the automatic
tire loader. This automatic tire loader 10 is utilized in systems
and methods for automated truck loading. A tractor trailer, for
example, 12 having an operator cab 14 is towing a trailer 16, which
may be an ocean freight container, for example, having a front wall
18, two side walls 20A, 20B (best seen in FIGS. 6A through 6D, for
example), a floor 22, a ceiling 24, and a rear access opening 26
accessible due to an open door. As alluded to, as used herein,
trailer includes ocean freight containers and similar transport and
logistic structures. A bumper 28 of the trailer 16 is backed up to
a loading bay 30 of loading dock 32 such that the bumper 28 touches
a bumper 34 of the loading bay 30. A dock plate 36 bridges the gap
between the floor 22 and a deck 38 of the loading dock 32.
[0033] As will be described in further detail hereinbelow, under
the supervision of the distance measurement subassembly that is a
component of the automatic tire loader 10, the automatic tire
loader 10 maneuvers and drives automatically into the trailer 16 to
a position proximate to the front wall 18. It should be appreciated
that although an operator is not depicted as operating the
automatic tire loader 10, an operator may interact with the
equipment, although unnecessary. The automatic tire loader 10
operates independently of an operator and an operator is only
necessary for certain types of troubleshooting, maintenance, and
the like. A telescoping conveyor unit 42 is connected to the
automatic tire loader 10. A stream of product 46, in the form
standard tires 46A-46H, which may be of any dimension, radius,
and/or tread, is being supplied by the telescoping conveyor 42
which, in turn, loads the product 46 into the trailer 16. In
particular, the automatic tire loader 10 has already stacked tires
46F, 46G and others, 46H, for example, at the intersection of the
front wall and the floor 22. The automatic tire loader 10
alternates between loading the tires 46 and reversing to create
more space for the tires 46 between the front wall 18 and the
automatic tire loader 10 until the trailer 16 is at least partially
loaded of tires 46.
[0034] FIG. 2A through FIG. 2G and FIG. 3A through FIG. 3B depict
the automatic tire loader 10 in further detail. A mobile base 50
supports a drive subassembly 52, a conveyance subassembly 54, an
industrial robot 56, a positioning subassembly 58, a safety
subsystem 60, and a control subassembly 62, which interconnects the
drive subassembly 52, conveyance subassembly 54, industrial robot
56, positioning subassembly 58, and safety subsystem 60. The mobile
base 50 includes a front end 64 and a rear end 66 as well as sides
68, 70, a surface 72, and an undercarriage 74.
[0035] The drive subassembly 52 is coupled to the undercarriage 74
of the mobile base 50 to provide mobility. As will be discussed in
further detail hereinbelow, drive wheel assemblies 78, 80, are
disposed on the undercarriage 74 proximate to the sides 70, 68
respectively. A universal wheel assembly 82 is disposed on the
undercarriage 74 more proximate to the rear end 66 and centered
between the sides 68, 70, respectively. In combination, wheel
assemblies 78, 80, 82 provide forward and reverse drive and
steering. Retractable stabilization assemblies 84, 86 are also
disposed on the undercarriage 74 proximate to the intersection of
the end 64 and side 68, the intersection of end 66 and the side 70,
respectively. As alluded to, in a forward or reverse drive and
steering operation, such as moving into or out of the trailer 16,
drive wheel assemblies 78, 80 and the universal wheel assembly 82
are actuated and in contact with the deck 38 of the loading dock 32
while the retractable stabilization assemblies 84, 86 are withdrawn
from contact with the deck 38 in a position close to the
undercarriage 74. On the other hand, when the automatic tire
loader/unloader 10 is conducting a tire loading or unloading
operation, such as during the use of the industrial robot 56, the
retractable stabilization assemblies 84, 86 are positioned in
contact with the deck 38 to anchor the automatic tire
loader/unloader 10.
[0036] The conveyance subassembly 54 is disposed on the surface 72
of the mobile base 50 to provide a powered transportation path 88
operable for measuring, separating, carrying, and stacking, as
required by the application and job assignment of the automatic
tire loader/unloader 10, tires from the rear end 66 to the front
end 64 proximate to the industrial robot 56. As shown, the powered
transportation path 88 includes a powered roller conveyor 90 having
roller elements 92 which deliver the tires 46 to a landing platform
94 where manipulation by the industrial robot 56 is initiated. It
should be appreciated that although only a single powered roller
conveyor is display, the powered transportation path 88 may include
any combination and type of conveyors, elevators, stackers, and
bypasses and the particular combination of components selected for
the powered transportation path 84 will depend upon the particular
tires or other product and application of the automatic tire
loader/unloader 10.
[0037] The conveyance subassembly 54 as well as the telescoping
conveyor unit 42 may also each be equipped with a series of end
stop photo eyes to adjust the rate of automatic flow of product
through the telescoping conveyor unit 42 and the conveyance
subassembly 54. Such an implementation provides a steady and
continuous flow of product, maintains proper tire or product
separation, and prevents unnecessary gaps between the product and
product backups and jams.
[0038] A telescoping conveyor interface 104 couples the roller
conveyor 90 of the conveyance subassembly 54 to the telescoping
conveyor unit 42 and the rest of a pick belt system which may be at
the warehouse associated with the loading dock 32. Auto-follow
circuitry associated with the telescoping interface 104 of the
telescoping conveyor unit 42 and the conveyance subassembly 54 may
utilize fiber optic sensors at the last boom of the telescoping
conveyor unit detect reflective tape at the edge of the conveyance
subassembly to cause the telescoping conveyor unit 42 to extend and
retract to maintain the proper position with respect to the
automatic tire loader/unloader 10. In another embodiment, the
telescoping conveyor unit 42 may be passive and other elements may
provide the force required to extend or retract.
[0039] The industrial robot 56 is disposed at the front end 64 and
adapted to provide selective articulated movement of an end
effector 130 between the landing platform 94 of the powered
transportation path 88 and a reachable space 132 such that the
industrial robot 56 is operable to place the product 46 in the
reachable space 132. The end effector 130 includes a gripper arm
134 adapted for manipulating product with opposing grapplers 136A,
136B. It should be appreciated that any type of end effector 130
may be employed the industrial robot and the choice of end effector
130 will depend upon the product 46 and specific automatic tire
loader 10 application. By way of example, the gripper arm 134 with
opposing grapplers 136A, 138B is preferred for loading tires
46A-46H. It should be understood, however, that the product 46 may
be any type of good such as other non-tire objects requiring
loading.
[0040] In one implementation, the industrial robot 56 includes
seven segments 130, 138, 140, 142, 144, 146, 148 joined by six
joints 150, 152, 154, 156, 158, 160 to furnish selective
articulated movement having six degrees of freedom. More
particularly, the referenced reachable space 132, as best seen in
FIGS. 2F and 2G, is defined by the movement of the industrial robot
56 which provides rotation about six axes including rotary movement
of the entire industrial robot 56 about a primary vertical axis;
rotary movement of segment 146 having a tower structure about
horizontal axis to provide extension and retraction of the segment
144 having a boom arm; rotary movement of the boom arm about the
horizontal axis to provide raising and lowering of the boom arm;
and selective rotary movement about three wrist axes.
[0041] The positioning subassembly 58 is dispersed throughout the
mobile base 50. A distance measurement subassembly 170 disposed at
the front end 64 of the mobile base 50 measures distance and
determines the presence of objects within a detection space 172
which is located in front of the front end 64. In one embodiment,
the detection space 172 and the reachable space 132 at least
partially overlap. The distance measurement subassembly 170 assists
the automatic tire loader/unloader 10 with forward and reverse
movement and the repositioning of the automatic tire loader 10 to
create additional empty reachable space 132 for the placement of
the product 46. Further, the distance measurement subassembly 170
assists with the coordination and operation of the industrial robot
56. Distance and measurement information gathered by the distance
measurement subassembly 170 is provided to the control subassembly
62.
[0042] As will be discussed in further detail hereinbelow, the
distance measurement subassembly 170 may be a laser range finding
apparatus operating on a time-of-flight measurement basis or
principle, or a three-dimensional camera system, for example. It
should be appreciated, however, that other types of distance
measurements are within the teachings of the present invention. By
way of example, and not by way of limitation, the distance
measurement subassembly may include a laser range finding
apparatuses, ultrasonic measurement apparatuses, inclinometers,
camera systems, and combinations thereof. Similar to distance
measurement subassembly 170, distance measurement subassemblies
174, 176 are respectively disposed at the sides 68, 70 and,
depending on the application, may or may not be required. The
distance measurement subassemblies 174, 176 each include detection
spaces (not illustrated) to provide measurement and distance
information to the control subassembly during traverse movement
operations of the automatic tire loader/unloader 10.
[0043] The safety subsystem 60 is distributed and mounted to the
mobile base 50. The safety subsystem 60 may include a light tower
which provides a quick indication of the current status of the
automatic tire loader/unloader 10 to an operator and a wireless
operator alert system 182 which contacts pagers or cellular devices
of individuals through a wireless network. Also a cage and railing
may be included around the operator platform 40 to provide
additional safety to the operator. Emergency buttons may be located
throughout the automatic tire loader/unloader 10 to provide for
instant and immediate power down. Front safety bumpers or,
alternatively, scanners 188 and rear safety scanners 190 may be
positioned at the front end 64 and the rear end 64 to protect the
automatic tire loader/unloader 10, people, and product during a
collision with an obstacle. Additionally, the front safety scanners
188 and the rear safety scanners 190 may include detectors that
detect the presence of an object and cause an automatic power down
during a collision. Side safety bumpers, although not illustrated,
may also be utilized. It should be appreciated that other safety
features may be integrated into the automatic tire loader/unloader
10.
[0044] The control subassembly 62, which is also distributed and
mounted to the mobile base 50, may include control station having a
user interface disposed at the side 70 near the rear of the mobile
base 76. As discussed, the drive subassembly 52, the conveyance
subassembly 54, the industrial robot 56, the positioning
subassembly 58, and the safety subassembly 60 are interconnected
and in communication with the control subassembly via a network of
concealed and sheathed cables and wires. With this arrangement, the
control subassembly 62 may coordinate the manual and automatic
operation of the automatic tire loader/unloader 10.
[0045] A main frame 200 is constructed of welded steel tubing
includes tubular sections 202, 204, 206, and 208 which provide a
rectangular framework. The tubular sections 202-208 are supported
by tubular sections 208, 210, 214, 216, 218, and 220, which augment
and further support the rectangular framework. All mounting plates,
such as mounting plates 222, 224 and bolt holes necessary to hold
the various components attached to the mobile base 50 are included
in the main frame 200. The large plates 222, 224 hold, for example,
the control station and the user interface in position while
providing counter weight for the automatic tire loader/unloader 10
as well as balance with respect to the industrial robot 56 disposed
proximate to the mounting plates 222, 224. Additional counter
weight may be supplied by tractor weights mounted proximate to the
rear end 66, which also serve to add additional support and
integrity to the main frame 200.
[0046] Drive wheel assemblies 78, 80 include a pair of front drive
wheels 252, 250 disposed proximate to the front end 64 and, more
particularly, proximate the intersection of tubular sections 208,
214 and tubular sections 204, 214, respectively. Respective AC
motors 254, 256 with double reduction gearboxes 258, 260 supply
power thereto. The AC motor 254 with double reduction gearbox 258
is disposed adjacent to the tubular section 214 and the front drive
wheel 250. Similarly, the AC motor 256 with double reduction
gearbox 260 is disposed adjacent to the tubular section 214 and the
front drive wheel 252. The universal wheel assembly 82 includes a
rear steering wheel 284 mounted to a frame 286 disposed proximate
to the rear end 66.
[0047] With reference to the operation of the drive subassembly 52
in conjunction with the mobile base 50, the drive wheel assemblies
78, 80 and universal wheel assembly 82 provide mobility along the
length of the automatic tire loader 10. The AC motors 254, 256 with
the respective double reduction gearboxes 258, 260 drive the front
drive wheels 250, 252. In particular, each front drive wheel 250,
252 is independently driven to provide the ability to turn and to
provide a pivoting drive mode. The universal wheel assembly 82
provides a rear steering wheel 284 to provide enhanced steering
capability for the automatic tire loader 10. In addition to
providing forward and reverse capability, the one embodiment, the
drive subassembly 52 may furnish a traverse drive system providing
the capability to move the entire automatic tire loader 10
perpendicular to a trailer or fixed object at the loading dock
32.
[0048] Referring now to FIGS. 4A through 4C and FIGS. 5A through
5C, wherein an end effector 130 having gripper arm 134 with
opposing grapplers 136A, 136B is depicted positioned to grip a tire
46 in FIGS. 4A through 4C and is actively gripping a tire in
corresponding FIGS. 5A through 5C. More particularly, the end
effector 130 includes a support frame 300 for attachment to the
industrial robot 56 and the support frame 300 includes housings
302, 304 having guide tracks 306, 308 radially offset and spaced
apart. Retaining elements 310, 312 are mounted to the support frame
300 and include respective tire contacting surfaces 314, 316
configured to contact the tire 46. Selectively moveable elements
318, 320 are mounted on the respective guide tracks 306, 308 for
transverse movement along the housings 302, 304 of the support
frame and superposed extension and retraction thereabove to provide
for the action of the opposing grapplers 136A, 136B. The
selectively moveable elements 318, 320 include deviated contact
plates 322, 324 configured to contact the tire 46 at an inner
radius. In operation, by extension and retraction of the opposing
grapplers 136A, 136B the tire 46 may be gripped at the inner radius
and released.
[0049] FIGS. 6A through 6D depict one operational embodiment of the
automatic tire loader 10 stacking tires 46A-46G in the trailer of
the truck. Referring now to FIG. 6A, tires 46A-46G are positioned
in an empty trailer of the truck in a rick-rack stacking pattern by
the automatic tire loader/unloader 10. More specifically, the
distance measurement subassembly 170 continuously determines the
position of the automatic tire loader/unloader 10 within the
trailer and the presence of objects, including tires 46, is known.
When beginning a rick-rack pattern, the automatic tire
loader/unloader 10 identifies an empty tire skyline 330 and chooses
an active quadrant 332 to begin stacking operations. A sequential
tire placement direction 334 is also identified such that the
active quadrant 332 advances horizontally across the trailer 16 of
the truck. Initially, within the active quadrant 332, a placement
angle .alpha. is specified for the placement of the first tire 46A.
Thereafter, for tires 46B-46G, placement angles .alpha. are
determined and the automatic tire loader/unloader 10 with the use
of the end effector 130 places the tires 46B-46G, where as shown
tire 46G is being placed.
[0050] With reference to FIG. 6B, with the first row of tires
46A-46G complete, the tire skyline 330 is identified and within the
tire skyline 330 a hole and a bump of an adjacent tire pair is
identified. For example, hole 336 and bump 338 of tires 46A, 46B is
identified to determine tire 46M should be placed adjacent to tire
46L and superposed on tires 46A, 46B. With reference to FIG. 6C,
this methodology continues with the skyline 330 and activity in
quadrant 332, from which the sequential placement direction 334
will advance. The hole 336 is identified with tire 46M and the side
wall 20B of the trailer serves as the bump for placement of the
tire 46N. The sequential tire placement continues until the trailer
of the truck is filled as shown in FIG. 6D, with 3A tires, 46A-46Z
and 46AA-46MM.
[0051] FIGS. 7A through 7D depict one operational embodiment of the
automatic tire loader 10 unstacking tires in the trailer 16 of the
truck. In FIG. 7A, the unstacking methodology begins by the
identification of the tire skyline 330 and the active quadrant 332
from which sequential tire removal will advance as identified by
number 340. Bump 338 and hole 336 of the adjacent tire pair are
identified and as shown in FIG. 7B, the tire 46MM is removed
following the automatic tire loader/unloader 10 providing the
appropriately calculated instructions for removing tires from the
rick-rack pattern. This methodology continues in FIGS. 7C and 7D,
wherein upon reaching the bottom row, the automatic tire
loader/unloader sequentially removes the last row of tires
46A-46G.
[0052] Referring now to FIGS. 8A through 8D, wherein one embodiment
of an automated tire loading system and methodology are illustrated
for the automatic tire loader/unloader 10 of the present invention.
Initially, as shown in FIG. 8A, the trailer 16 is positioned under
the power of the tractor trailer 12 at the loading bay 30 of the
loading dock 32 approximate to the deck 38 where the automatic tire
loader/unloader 10 is working. The trailer 16 is set-up, cleaned,
and activated in a usual manner. The dock plate 36 is deployed from
the loading bay 30 into the trailer 16 to provide a bridge.
Thereafter, the trailer 16 is inspected for significant damage that
may interfere with the automated loading operations of the
automatic tire loader/unloader 10. Additional inspection may
include ensuring the trailer is reasonably centered within the
loading bay 30 and ensuring the deck 38 is clear of any
obstructions. At this time, by way of further safety measures, a
kingpin lockout may be installed to prevent a driver from
accidentally pulling out the trailer 16 from the loading bay 30
when the automatic tire loader/unloader 10 is operating within the
trailer 16. The kingpin lockout or similar safety precautions
protect both the operator 40 and the equipment and ensures that the
wheels of the trailer 16 are chocked and will not roll during the
use of the automatic tire loader 10.
[0053] Continuing to refer to FIG. 8A, once the trailer 16 is
positioned in the loading bay 30, the automatic tire
loader/unloader 10 is moved in front of the rear access opening of
the trailer 16. The automatic tire loader/unloader 10 utilizes
either a manual or automatic reverse mode to assist the operator
(whether on the automatic tire loader/unloader 10 or at a remote
location) in backing the automatic tire loader/unloader 10 up to
the telescoping conveyer unit 42 in a position that is square
thereto. The conveyance subassembly 54 of the automatic tire loader
10 is then coupled to the telescoping conveyor unit 42. At this
time, as the dock plate 36 has been positioned from the deck 38 to
the trailer 16, the automatic tire loader/unloader 10 may be
advanced into the interior of the trailer 16.
[0054] With reference to FIG. 7B, the automatic tire
loader/unloader 10 has advanced forward into the trailer 16 and, in
one embodiment, the positioning subassembly 58 and, in particular,
the distance measurement subassembly 170 continuously determines
the position of the automatic tire loader/unloader 10 within the
trailer 16. More specifically, several measurements are made. The
position and angle of the automatic tire loader/unloader 10 are
measured with respect to the sidewalls 20A, 20B and an interior
width defined thereby. Also, measurements are made with respect to
a near wall within the trailer 16 and the floor 22. The near wall
being the closer of the front wall 18 of the trailer or the edge
formed by product 46, e.g. tires, positioned within the trailer 16.
The angle relative to the floor 22 proximate to the automatic tire
loader/unloader 10 is measured as the automatic tire
loader/unloader traverses the dock plate 36 and moves into the
trailer 16. In one embodiment, following successful traversal, the
angle relative to the floor 22 may be assumed to be constant.
[0055] In this way, as the automatic tire loader/unloader 10 moves,
the position of the automatic tire loader/unloader 10 relative to
objects in its environment, including tires, is known and the
automatic tire loader 10 may adjust operation appropriately.
Adjustments in operation may include, but are not limited to, the
operation of the industrial robot 56, the operation of the
conveyance subassembly 54, and the actuation of the drive
subassembly 52. The position of the sidewalls 20A, 20B and the near
wall is utilized to determine the position of the automatic tire
loader 10 along the length of the trailer 16, the position across
the width of the trailer 16, and the automatic tire loader's angle
relative to the sidewalls 20A, 20B or yaw. The measurements also
determine the position of the automatic tire loader/unloader 10
relative to the floor 22 of the trailer 16. To assist the automatic
tire loader/unloader 10 in determining position within the trailer
16, in one implementation, the automatic tire loader/unloader 10 is
programmed with the dimensions of the trailer 16.
[0056] Additionally, in one embodiment, the automatic tire
loader/unloader 10 is programmed with the reachable space 132 of
the industrial robot 56. As illustrated, once the automatic tire
loader/unloader is positioned proximate to the front wall 18 of the
trailer 16 such that the placement of tires 46 against the front
wall 18 of the trailer 16 is within the reachable space 132 of the
industrial robot 56, the automatic tire loader/unloader 10 stops
advancing. Continuing to refer to FIG. 8B, tires 46 are conveyed
from the telescoping conveyor unit 42 to the conveyance subassembly
54 and this stream of tires 46 is presented to the industrial robot
56. With selective articulated movement through the reachable space
132, the industrial robot 56 places the tires 46 within the trailer
and sequentially loads the tires 46 according to a stacking routine
designed to optimize the use of available space within the trailer
16. For example, the stacking routine may be the rick-rack stacking
pattern presented in FIGS. 6A through 7D or vertically stacked
tires.
[0057] In the illustrated embodiment, this stacking routine places
product in sequentially rick-rack stacked rows. By way of example,
FIG. 8B illustrates a first rick-rack stacked row 344A being
completed. This stacking routine or other alternative stacking
routine may be optimized for the size of the end effector 130 of
the industrial robot 56, the dimensions of the trailer 16, and the
dimensions of the product 46.
[0058] As depicted in FIG. 8C, the automatic tire loader/unloader
10 has completed stacking multiple horizontal rows 344A-344D of
tires 46. The loading of the tires 46 by the industrial robot 56 is
temporarily interrupted in response to the distance measurement
subassembly 170 detecting the presence of the tires 46 within the
reachable space 132. Further, with this information being available
to the control subassembly 62, a signal may be sent to the
conveyance subassembly 54 to slow down or temporarily halt the
powered transport of the product 46.
[0059] As a result of the completion of a row, such as rows
344A-344D, the automatic tire loader/unloader 10 periodically
reverses and repositions to refresh the reachable space 132 such
that the automatic tire loader/unloader 10 is positioned proximate
to the wall of placed tires 46 in order that the placement of
additional tires 46 against the wall of placed tires 46 is within
the reachable space 132 of the industrial robot 56. During the
repositioning of the automatic tire loader/unloader 10, the
telescoping conveyor unit 42 appropriately retracts, while
maintaining contact with the conveyance subassembly 54, to
accommodate the new position of the automatic tire loader/unloader
10.
[0060] Referring to FIG. 8D, the iterative stacking operations and
repositioning of the automatic tire loader/unloader 10 described in
FIGS. 8A through 8C continues and the trailer 16 is filled. With
respect to FIG. 8D, the trailer 16 is completely filled with tires
46, including rows 344A-344F, and the automatic tire loader 10 is
reversed to a position entirely on the deck 38. Thereafter, the
trailer 16 filled with tires may leave the loading dock 32 and a
fresh empty trailer may then be positioned at the loading bay 30
and loaded in the manner described herein.
[0061] FIGS. 9A through 9D depict the iterative unstacking
operations and repositioning of the automatic tire loader/unloader
10. As shown, the automatic tire loader/unloader 10 unstacks tires
46 from the filled trailer having rows 344A-344I in a manner
opposite to that described in FIGS. 8A through 8D until the trailer
16 is empty in FIG. 9D.
[0062] FIG. 10 depicts one embodiment of the automatic tire
loader/unloader 10 in which the automatic tire loader/unloader is
schematically depicted to include a computer-based architecture
including a processor 350 coupled to a bus 352 having
transmitter/receiver circuitry 354, outputs 356, inputs 358, memory
360, and storage 362 interconnected therewith. In one embodiment,
the control assembly 192 includes the memory 360, which is
accessible to the processor 350. The memory 360 includes
processor-executable instructions that, when executed cause the
processor 350 to execute instructions for stacking or unstacking
tires 46 or other objects. By way of example and not by way of
limitation, the instructions may be directed to stacking tires in a
rick-rack or vertical pattern or unstacking tires from a rick-rack
or vertical pattern. With respect to stacking tires in a rick-rack
pattern, the instructions may include specifying a search operation
to identify a tire skyline including an active quadrant, specifying
a search operation to identify a hole and hump of an adjacent tire
pair within the active quadrant, specifying a search operation to
identify the sequential tire placement direction, and the
calculation of instructions for executing a rick-rack stacking
pattern of tires.
[0063] Other types of tire stacking/unstacking operations involve
other types of instructions. Removing tires, whether from a
rick-rack or vertical stack, requires a search operation to
identify the sequential tire removal direction. Further, operations
may specify instructions for executing a rick-rack unstacking
pattern of tires, instructions for executing a vertical stacking
pattern of tires, or instructions for executing a vertical
unstacking pattern of tires, for example. It should be appreciated
that although a specific computer architecture is depicted in FIG.
10, other architectures are within the teachings presented
herein.
[0064] FIG. 11 depicts one embodiment of the automatic tire
loader/unloader 10 and the control signals associated therewith,
which may be deployed across the computer architecture shown in
FIG. 10, for example. The illustrated components coordinate the
various functions and operations of the automatic tire
loader/unloader 10. The user interface 194, operational environment
database 370, programmable logic controller 372, robot controller
374, and distance measurement subassemblies 170, 174, 176 are
interconnected. The drive subassembly 52, conveyance subassembly
54, as represented by control 376 for conveyors/elevators, and
safety controller 378 are connected to the programmable logic
controller 372. Finally, the industrial robot 56 is connected to
the robot controller 374. In one implementation, the user interface
194, operational environment database 370, and programmable logic
controller 372 are part of the control subassembly 62 and the robot
controller 374 forms a portion of the industrial robot 56. The
safety controller 358 is included in the safety subsystem 60 and
provides operation to the aforementioned components of this
subsystem.
[0065] The user interface 194 provides user control and interaction
with the automatic tire loader/unloader 10. The user interface 194
may utilize icons in conjunction with labels and/or text to provide
navigation and a full representation of the information and actions
available to the operator. In addition to loading operations, user
interactions may be related to maintenance, repair and other
routine actions which keep the automatic tire loader 10 in working
order or prevent trouble from arising.
[0066] The operational data environment database 370 includes data
about the reachable space 132 of the industrial robot 56, stacking
methodology data, product information as well as information about
the standard sizes of trailers. The product information may be
stored in the operational data environment database 350, gathered
by the conveyance subassembly 54 as previously discussed, or gained
by a combination thereof. By having the standard sizes of trailers
pre-loaded, operator time is saved from having to enter this data
and performance of the automatic tire loader/unloader 10 is
improved with this additional information. By way of example,
Tables I & II present exemplary examples of type of trailer
data that the automatic tire loader/unloader 10 may utilize in
determining position and product placement.
TABLE-US-00001 TABLE I TRAILER DIMENSIONS Trailer Inside Inside
Height Inside Height Door Opening Type Length Width Center Front
Width 28' (8.5 m) 27'3'' (8.3 m) 100'' (2.5 m) 109'' (2.8 m) 107''
(2.7 m) 93'' (2.4 m) High Cube 45' (13.7 m) 44'11/2'' (13.4 m) 93''
(2.4 m) 109'' (2.8 m) 106'' (2.7 m) 87'' (2 m).sup. Wedge 48' (14.6
m) 47'3'' (14.4 m) 99'' (2.5 m) 1101/2'' (2.8 m) 1081/2'' (2.8 m)
93'' (2.4 m) Wedge
TABLE-US-00002 TABLE II TRAILER DIMENSIONS CONTINUED Trailer Door
Opening Rear Floor Cubic Overall Overall Type Height Height
Capacity Width Height 28' (8.5 m) 104'' (2.6 m) 471/2'' (1.2 m)
2029 cft (57.5 cm) 102'' (2.6 m) 13'6'' (4.1 m) High Cube 45' (13.7
m) 1051/2'' (2.7 m) 50'' (1.3 m) 3083 cft (7.3 cm) 96'' (2.4 m)
13'6'' (4.1 m) Wedge 48' (14.6 m) 105'' (2.7 m) 481/2'' (1.2 m)
3566 cft (101 cm) 102'' (2.6 m) 13'6'' (4.1 m) Wedge
[0067] The programmable logic controller 372 coordinates overall
operation and switches between various modes of operation including
manual and automatic. The programmable logic controller 372 also
provides for the high-level calculation and coordination required
during automatic operation for items such as the current
loading/unloading quadrant and steering angel calculations during
automatic navigation.
[0068] The robot controller 374 controls the motions of the
industrial robot 56 through built in inputs and outputs wired
through the industrial robot 56 and the end effector 130. It should
be appreciated that although a particular architecture is presented
for the control of the automatic tire loader, other architectures
are within the teachings of the present invention. By way of
example, any combination of hardware, software, and firmware may be
employed. By way of further example, the distribution of control
may differ from that presented herein.
[0069] In one operation embodiment, the programmable logic
controller 372 accesses the dimensions of the trailer 16 from the
operational environment database 372. The operator 40 has indicated
through the user interface 194 which type of trailer has arrived at
the docking bay 30. Alternatively, the distance measurement
subassembly 170 is operable to detect this information. The
distance measurement subassembly, which may include various
components 170, 174, 176, relays distance and position data to the
programmable logic controller 352 which uses this information to
send control signals to the robot controller 374, the drive
subassembly 52, the controller 372, and the safety controller 378.
Additionally, the programmable logic controller 372 receives
control signals, which are inputs into the behavior process, from
each of these components. Constant updates and status information
are provided to the operator 40 by the programmable logic
controller 352 through the user interface 194.
[0070] FIG. 12 depicts one embodiment of the robot controller 372
which forms a portion of the automatic tire loader 10. The essence
of the robot control 372 is a robot system or control program 380,
which controls the industrial robot 56. The control program 380 can
be operated by the operator 40 by means of an operating service 362
in communication with the user interface 194 and receives input
data (as well as provide instructions, as appropriate) from the
operational environmental database 370, programmable logic
controller 372, and distance measurement subassembly 170 by means
of a driver 384. It should be appreciated, that the independence of
the robot controller 374 may vary. In one implementation, the robot
controller 374 may be under the control of the programmable logic
controller 374. In another implementation, as illustrated, the
robot controller 374 is more autonomous and may include features
such as direct connection to the user interface 194.
[0071] According to one embodiment, between the driver 384 and the
control program 380 is provided an independent data processing
layer in the form of a frame program 386, which controls the robot
movements, and a unit 388 for automated or event-controlled
strategy or behavioral selection on the basis of the states and
signals which occur. User application programs, event-controlled
strategy selections and sensor programs in the frame program 386
can be programmed by the operator 40 and directed by a robot
program 390, which monitors the balance and implementation of
manual and automatic control of the industrial robot 56.
[0072] FIG. 13 depicts one embodiment of a distance measurement
subassembly, i.e., a laser measurement sensor 400. A staging
circuit 402 causes a pulsed laser 404 to transmit light pulses
while causing the rotation of a light deflecting device 406 via
controller 408 which may be equipped with a rotational means and a
motor. The angular position of the light deflecting device 406 is
continuously communicated to the staging circuit 402 by the
controller 408. Light pulses are transmitted into the detection
space 172 via the transmitter lens and the mirrors associated with
the light deflection device 406. More particularly, when the rotary
mirror of the light deflection device 406 is driven by the
controller 408 to execute a continuous rotary movement, the staging
circuit 402 causes the pulsed laser 404 to transmit a light pulse.
The light pulse is transmitted into the detection space 172 and is
reflected from an object, so that finely a received pulse enters
into a photo receiving arrangement 410. In this manner the light
reaches the photo receiver arrangement 410 after a light transit
time t of 2d/c, where d is the space in the object from the
apparatus and c is the speed of light.
[0073] The time t between the transmission and reception of the
light pulse is measured with the aid of a comparator 412 having
time interval computer functionality. On transmitting the light
pulse, a counter function within the comparator 412 is triggered
and is stopped again by the photo receiver arrangement 410 via the
comparator 412 on receiving the light pulse from the detection
space 172.
[0074] A corresponding electrical signal is formed and applied via
comparator 412 to a laser scanner controller 414, signal to noise
processor 416 and a detector 418, which analyzes the signal for
objects and in the instant example determines that an object is
present. The task of the signal to noise processor 416 is to
control the detection threshold independence on the received noise
level. This control ensures a constant false alarm rate with
varying illumination situations and object reflection factors. The
signal to noise processor 416 makes available this information to
the laser scanner controller 414. The laser scanner controller 414
performs peak value calculations based on the data from the
comparator 412, the signal to noise processor 416, and the detector
418.
[0075] As the laser scanner controller 414 knows the instantaneous
angular position of the light pulses by way of communication with
the staging circuit 402, the laser scanner controller 414
determines the location of the object and other navigational
properties. The laser scanner controller 414 is adapted to forward
this information to other components.
[0076] FIG. 14 is a schematic diagram of a distance measurement
subassembly 170, which is depicted as a three dimensional (3-D)
measurement system 450, which includes an illumination assembly 452
and an image capture subassembly 454 that together utilize a laser
and/or infrared-based camera application employing an adaptive
depth principle. The illumination assembly 452 includes a light
source 456 and a transparency 458, which may include a positive
image on a transparent support with a various sorts of fixed,
uncorrelated patterns of spots, for example.
[0077] The light source 456 transilluminates transparency 458 with
optical radiation so as to project an image of the spot pattern
that is contained by the transparency onto object 46A, which is
depicted as the tire, but may also include various environmental
information about the storage container. The image capture assembly
454 captures an image of the pattern that is projected by
illumination assembly 452 onto tire 46A. The image capture assembly
454 may include objective optics 464, which focus the image onto an
image sensor 460. Typically, the image sensor 460 includes a
rectilinear array of detector elements 462, such as a CCD or
CMOS-based image sensor array.
[0078] As should be appreciated, although the illumination assembly
and image capture assembly are shown as held in a fixed spatial
relation, various other positioning techniques may be employed to
create a dynamic relationship therebetween. Moreover, the
three-dimensional x, y, z axis may be employed in this regard. To
generate a 3D map of object or tire 46A, including the environment,
a processor, which may incorporated into processor 350 or
associated therewith, compares the group of spots in each area of
the captured image to the reference image in order to find the most
closely-matching group of spots in the reference image. The
relative shift between the matching groups of spots in the image
gives the appropriate x, y or Z-direction shift of the area of the
captured image relative to the reference image. The shift in the
spot pattern may be measured using image correlation or other image
matching computation methods that are known in the art. By way of
example, the operation principle may include an infrared adaptive
depth principle utilizing laser or infrared cameras.
[0079] While this invention has been described with reference to
illustrative embodiments, this description is not intended to be
construed in a limiting sense. Various modifications and
combinations of the illustrative embodiments as well as other
embodiments of the invention, will be apparent to persons skilled
in the art upon reference to the description. It is, therefore,
intended that the appended claims encompass any such modifications
or embodiments.
* * * * *