U.S. patent application number 10/392539 was filed with the patent office on 2003-09-25 for automotive safety glass edge polishing.
Invention is credited to Collins, Mark E., Koontz, Noah K..
Application Number | 20030181145 10/392539 |
Document ID | / |
Family ID | 28454763 |
Filed Date | 2003-09-25 |
United States Patent
Application |
20030181145 |
Kind Code |
A1 |
Collins, Mark E. ; et
al. |
September 25, 2003 |
Automotive safety glass edge polishing
Abstract
An apparatus for polishing an edge of an automotive glass sheet
comprising a retaining device, which is capable of supporting the
automotive glass sheet, and a polishing wheel assembly. A motor
assembly is coupled to and drives the polishing wheel assembly to
polish the edge of the automotive glass sheet to maximize the
strength of the glass sheet and improve the aesthetic properties
thereof. A pressure system, such as a compliant member, a robotic
system, or a floating spindle assembly, is coupled to either the
retaining device or the polishing wheel in order to actively
maintain a predetermined generally constant contact pressure
between the polishing wheel and the edge of the automotive glass
sheet to insure proper polishing thereof.
Inventors: |
Collins, Mark E.;
(Bellefontaine, OH) ; Koontz, Noah K.;
(Marysville, OH) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 828
BLOOMFIELD HILLS
MI
48303
US
|
Family ID: |
28454763 |
Appl. No.: |
10/392539 |
Filed: |
March 20, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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60366201 |
Mar 21, 2002 |
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Current U.S.
Class: |
451/41 |
Current CPC
Class: |
B24B 9/107 20130101;
B24B 55/02 20130101; B24B 49/16 20130101 |
Class at
Publication: |
451/41 |
International
Class: |
B24B 001/00 |
Claims
What is claimed is:
1. An apparatus for polishing an edge of automotive glass, the
apparatus comprising: a base; a retaining device operable to
support the automotive glass; a polishing wheel operable to polish
the edge of the automotive glass; a motor assembly driving the
polishing wheel; and a pressure assembly coupled to one of the
retaining device and the polishing wheel to actively maintain a
predetermined generally constant contact pressure between the
polishing wheel and the edge of the automotive glass.
2. The apparatus according to claim 1, further comprising: a
cooling system disposed generally adjacent to the polishing wheel,
the cooling system operable to deliver a cooling fluid to the
polishing wheel during a polishing operation.
3. The apparatus according to claim 1, further comprising: a chip
removal system disposed generally adjacent to the polishing wheel,
the chip removal system operable to remove debris during a
polishing operation.
4. The apparatus according to claim 1 wherein the retaining device
comprises: a suction pad connectable to the automotive glass, the
suction pad being selectively disengagable with the automotive
glass.
5. The apparatus according to claim 1 wherein the retaining device
comprises: a retaining arm clampingly connectable to the automotive
glass, the retaining arm being selectively disengagable with the
automotive glass.
6. The apparatus according to claim 1 wherein the pressure assembly
comprises: a first member pivotally coupled to the base; a second
member pivotally coupled to the polishing wheel; a third member
pivotally coupled between the first member and the second member;
and a biasing member biasing at least one of the second member and
the third member such that the polishing wheel is engagable with
the edge of the automotive glass, the biasing member actively
maintaining the predetermined generally constant contact pressure
between the polishing wheel and the edge of the automotive
glass.
7. The apparatus according to claim 6, further comprising: an
adjustment device for adjusting the biasing force of the biasing
member.
8. The apparatus according to claim 6 wherein the motor assembly
comprises: a motor; and a drive system drivingly interconnecting
the motor to the polishing wheel to rotatably drive the polishing
wheel.
9. The apparatus according to claim 8 wherein the drive system
comprises: a first drive shaft drivingly enmeshing with the motor,
the first drive shaft being driven in response to the motor; a
second drive shaft drivingly enmeshing with the polishing wheel;
and an intermediate drive member operably coupling the first drive
shaft to the second drive shaft, the intermediate drive member
being operable to transmit a driving force from the first drive
shaft to the second drive shaft.
10. The apparatus according to claim 9 wherein the intermediate
drive member is a drive belt.
11. The apparatus according to claim 9 wherein the intermediate
drive member is a third drive shaft.
12. The apparatus according to claim 1, further comprising: a
pressure sensor operably coupled to the pressure assembly, the
pressure sensor being operable to provide an output signal in
response to the generally constant contact pressure between the
polishing wheel and the edge of the automotive glass.
13. The apparatus according to claim 1 wherein the pressure
assembly comprises: a robotic arm assembly having a base and at
least one arm linkage, the retaining device being disposed at an
end of the at least one arm linkage, the robotic arm assembly being
actuatable into a plurality of positions.
14. An apparatus for polishing an edge of automotive glass, the
apparatus comprising: a base; a retaining device operable to
support the automotive glass; a polishing wheel operable to polish
the edge of the automotive glass; a motor assembly driving the
polishing wheel; a first member pivotally coupled to the base; a
second member pivotally coupled to the polishing wheel; a third
member pivotally coupled between the first member and the second
member; and a biasing member biasing at least one of the second
member and the third member such that the polishing wheel is
engagable with the edge of the automotive glass, the biasing member
actively maintaining the predetermined generally constant contact
pressure between the polishing wheel and the edge of the automotive
glass.
15. The apparatus according to claim 14, further comprising: a
cooling system disposed generally adjacent to the polishing wheel,
the cooling system operable to deliver a cooling fluid to the
polishing wheel during a polishing operation.
16. The apparatus according to claim 14, further comprising: a chip
removal system disposed generally adjacent to the polishing wheel,
the chip removal system operable to remove debris during a
polishing operation.
17. The apparatus according to claim 14 wherein the retaining
device comprises: a suction pad connectable to the automotive
glass, the suction pad being selectively disengagable with the
automotive glass.
18. The apparatus according to claim 14 wherein the retaining
device comprises: a retaining arm clampingly connectable to the
automotive glass, the retaining arm being selectively disengagable
with the automotive glass.
19. The apparatus according to claim 14, further comprising: an
adjustment device for adjusting the biasing force of the biasing
member.
20. The apparatus according to claim 14 wherein the motor assembly
comprises: a motor; and a drive system drivingly interconnecting
the motor to the polishing wheel to rotatably drive the polishing
wheel.
21. The apparatus according to claim 20 wherein the drive system
comprises: a first drive shaft drivingly enmeshing with the motor,
the first drive shaft being driven in response to the motor, the
first drive shaft being disposed within the first member; a second
drive shaft drivingly enmeshing with the polishing wheel, the
second drive shaft being disposed within the second member; and an
intermediate drive member operably coupling the first drive shaft
to the second drive shaft, the intermediate drive member being
operable to transmit a driving force from the first drive shaft to
the second drive shaft.
22. The apparatus according to claim 21 wherein the intermediate
drive member is a drive belt.
23. The apparatus according to claim 21 wherein the intermediate
drive member is a third drive shaft.
24. The apparatus according to claim 14, further comprising: a
pressure sensor operably coupled to one of the second member and
third member, the pressure sensor being operable to provide an
output signal in response to the generally constant contact
pressure between the polishing wheel and the edge of the automotive
glass.
25. An apparatus for polishing an edge of automotive glass, the
apparatus comprising: a retaining device operable to support the
automotive glass; a polishing wheel operable to polish the edge of
the automotive glass; a motor assembly driving the polishing wheel;
a robotic arm assembly having a base and at least one arm linkage,
the retaining device being disposed at an end of the at least one
arm linkage, the robotic arm assembly being actuatable into a
plurality of positions; and a biasing member biasing the polishing
wheel into a position engagable with the edge of the automotive
glass, the biasing member actively maintaining a predetermined
generally constant contact pressure between the polishing wheel and
the edge of the automotive glass.
26. The apparatus according to claim 25, further comprising: a
cooling system disposed generally adjacent to the polishing wheel,
the cooling system operable to deliver a cooling fluid to the
polishing wheel during a polishing operation.
27. The apparatus according to claim 25, further comprising: a chip
removal system disposed generally adjacent to the polishing wheel,
the chip removal system operable to remove debris during a
polishing operation.
28. The apparatus according to claim 25 wherein the retaining
device comprises: a suction pad connectable to the automotive
glass, the suction pad being selectively disengagable with the
automotive glass.
29. The apparatus according to claim 25 wherein the retaining
device comprises: a retaining arm clampingly connectable to the
automotive glass, the retaining arm being selectively disengagable
with the automotive glass.
30. The apparatus according to claim 25 wherein the motor assembly
comprises: a motor; and a drive system drivingly interconnecting
the motor to the polishing wheel to rotatably drive the polishing
wheel.
31. The apparatus according to claim 30, further comprising: a
pressure sensor operably coupled to the drive system, the pressure
sensor being operable to provide an output signal in response to
the generally constant contact pressure between the polishing wheel
and the edge of the automotive glass.
32. The apparatus according to claim 30 wherein the drive system is
a compliant drive system.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 60/366,201, filed on Mar. 21, 2002. The disclosure
of the above application is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention generally relates to automotive safety
glass and, more particularly, relates to an apparatus for reliable
and convenient edge polishing of automotive safety glass.
BACKGROUND OF THE INVENTION
[0003] As is well known, automotive glass is typically constructed
using generally flat sheets of glass, which are preferably sized to
minimize waste thereof. During processing of this glass, the sheets
are cut to size and subsequently treated in a tempering, bending,
and/or otherwise shaping process. However, it should be understood
that following this cutting step and preferably before further
processing, the edges of the sheet should be polished to minimize
burrs, reduce small peripheral fractures that could otherwise lead
to shattering, and produce an aesthetically pleasing product.
[0004] Frequently the polishing of the edge of the glass sheet is
accomplished through a machining process, which consists of passing
a fine grain polisher or a diamond wheel along the length of the
sheet edge. Typically, the environment is kept humid in order to
minimize the presence of air-borne glass dust during the polishing
process, while a cooling fluid flows over the polishing wheel.
[0005] However, conventional polishing wheel assemblies lack the
ability to accommodate slight variations in the glass sheets and
dimensional changes of the polishing wheel caused by wear. That is,
as the polishing wheel is polishing the edge of the glass sheet,
the grinding properties, such as the contact pressure on the glass
sheet, invariably change due to variations in the dimensions of the
glass sheet and/or polishing wheel. These dimensional variations
between the glass sheet and polishing wheel result in changes in
contact pressure, thereby resulting in polishing variations or even
stress fractures.
[0006] Accordingly, there exists a need in the relevant art to
provide an apparatus for polishing the edge of automotive safety
glass that is capable of maximizing the strength of the glass sheet
and improving the aesthetic properties thereof. Furthermore, there
exists a need in the relevant art to provide an apparatus for
polishing the edge of automotive safety glass that is capable of
maintaining a constant and consistent contact pressure between the
glass sheet and the polishing wheel. Additionally, there exists a
need in the relevant art to provide an apparatus for polishing the
edge of automotive safety glass that overcomes the disadvantages of
the prior art.
SUMMARY OF THE INVENTION
[0007] According to the principles of the present invention, an
apparatus is provided for polishing an edge of an automotive glass
sheet. The apparatus comprises a retaining device, which is capable
of supporting the automotive glass sheet, and a polishing wheel
assembly. A motor assembly is coupled to and drives the polishing
wheel assembly to polish the edge of the automotive glass sheet to
maximize the strength of the glass sheet and improve the aesthetic
properties thereof. A pressure system, such as a compliant member,
a robotic system, or a floating spindle assembly, is coupled to
either the retaining device or the polishing wheel in order to
actively maintain a predetermined generally constant contact
pressure between the polishing wheel and the edge of the automotive
glass sheet to insure proper polishing thereof.
[0008] Further areas of applicability of the present invention will
become apparent from the detailed description provided hereinafter.
It should be understood that the detailed description and specific
examples, while indicating the preferred embodiment of the
invention, are intended for purposes of illustration only and are
not intended to limit the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The present invention will become more fully understood from
the detailed description and the accompanying drawings,
wherein:
[0010] FIG. 1 is a perspective view illustrating a first embodiment
of the present invention employing a floating spindle apparatus
having a pressure control device; and
[0011] FIG. 2 is a perspective view illustrating a first embodiment
of the present invention employing a servo feedback robotic arm
assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] The following description of the preferred embodiments is
merely exemplary in nature and is in no way intended to limit the
invention, its application, or uses. For example, the principles of
the present invention may have utility in a wide variety of glass
processing applications, such as the polishing of laminated sheets,
tempered glass, or other application where glass sheets having
improved strength characteristics and aesthetic properties is
preferred.
[0013] Referring now to FIG. 1, an edge polishing apparatus,
generally indicated at 10, is provided for maintaining a constant
and consistent polishing pressure upon the edge of an automotive
glass sheet 12 according to a first embodiment of the present
invention. Edge polishing apparatus 10 generally includes a
moveable support structure 14, a glass sheet retaining device 16, a
conveyor assembly 18, a polishing wheel assembly 20, and a chip
removal system 22.
[0014] Preferably, glass sheet retaining device 16 is coupled to
conveyor assembly 18 such that automotive glass sheet 12 is carried
quickly and conveniently between processing stations (not shown)
during a complete manufacturing process. Although, the principles
of the present invention are intended to be employed in conjunction
with traditional processing steps, such as cutting, tempering,
laminating, bending, and the like, the present invention should not
be regarded as requiring such steps.
[0015] Still referring to FIG. 1, glass sheet retaining device 16
includes a plurality of retaining members 24, such as suction pads
or overlapping retaining arms. The plurality of retaining members
24 releasably secures automotive glass sheet 12 to glass sheet
retaining device 16 such that automotive glass sheet 12 may be
conveniently carried and transported by conveyor assembly 18.
[0016] Polishing wheel assembly 20 generally includes a motor 26
fixedly coupled to moveable support structure 14 to prevent
relative movement therebetween. Polishing wheel assembly 20 further
includes a polishing wheel 28 coupled to support structure 14
through a floating pressure assembly 30, which enables polishing
wheel 28 to move relative to support structure 14, yet maintain a
generally constant contact pressure with automotive glass sheet 12.
This relative movement between polishing wheel 28 and support
structure 14 accommodates dimensional and positional variations of
automotive glass sheet 12 and wear of polishing wheel 28.
[0017] Floating pressure assembly 30 includes a motor linkage or
shaft 32 extending from motor 26 and a wheel linkage or shaft 34
pivotally coupled to and driving polishing wheel 28. An
intermediate linkage or member 36 is pivotally coupled at one end
38 to an end 40 of motor linkage 32 to permit the pivoting movement
of intermediate linkage 36 about motor linkage 32. Intermediate
linkage 36 is further coupled at an opposing end 42 to an end 44 of
wheel linkage 34. Motor linkage 32, intermediate linkage 36, and
wheel linkage 34 thus cooperate to provide a flexing motion between
polishing wheel 28 and automotive glass sheet 12. A spring member
47 is coupled to either intermediate linkage 36 or wheel linkage 34
to bias polishing wheel 28 in a retracted position and into contact
with automotive glass sheet 12. The biasing force of spring member
47 is adjustable via an adjustment knob 49. Adjustment knob 49 is a
screw-type device that when "tightened" will increase the biasing
force of spring member 47, thereby increasing the contact pressure
of polishing wheel 28. Conversely, when adjustment knob 49 is
"loosened", the biasing force of spring member 47 is decreased,
thereby decreasing the contact pressure of polishing wheel 28.
[0018] Preferably, in order to ensure proper contact pressure
between polishing wheel 28 and automotive glass sheet 12, an
optional pressure sensor 48 is coupled between support structure 14
and intermediate linkage 36. Pressure sensor 48 is preferably a
pressure transducer capable of measuring the contact force between
polishing wheel 28 and automotive glass sheet 12. Pressure sensor
48 is more preferably adjustable to be set to a specific polishing
pressure setting. In operation, pressure sensor 48 could be
controlled by a linear variable displacement transformer that is
converted to torque or a differential amp draw on the motor created
by a position. This torque or differential amp draw may be used to
identify a unique position or applied force.
[0019] Polishing wheel 28 is generally circular in shape and
includes a polishing or grinding groove 50 extending therearound.
Preferably, polishing wheel 28 is made of a fine grain or diamond
material; however, it should be understood that polishing wheel 28
may be made of any material and have any cross-sectional profile
that maximizes the polishing effect of the glass sheet.
[0020] Polishing wheel 28 is driven through a drive system 51 that
is coupled to or disposed within floating pressure assembly 30. By
way of non-limiting example, the drive system may include a gearing
system disposed within the linkage members (i.e. a first drive
shaft 51a, a second drive shaft 51b, and an intermediate drive
member 51c), which are interconnected through known gearing
components. That is, the drive system may include a series of drive
shafts interconnected through a belt assembly and/or worm gear
systems. Ideally, first drive shaft 51a is directly coupled to
motor 26 so as to permit first drive shaft 51a to be driven in
response thereto. Intermediate drive member 51c is preferably a
belt extending between first drive shaft 51a/motor linkage 32 and
second drive shaft 51b/wheel linkage 34, which maintains a driving
connection even as polishing wheel 28 floats.
[0021] Still referring to FIG. 1, edge polishing apparatus 10
includes chip removal system 22 and a cooling system 52. Chip
removal system 22 is preferably a vacuum system that is capable of
removing, containing, and/or treating glass dust and other debris
produced during polishing. Cooling system 52 preferably includes
pump assembly 54 for pumping a cooling fluid from a sump 56 to an
outlet 58. Outlet 58 is preferably oriented such that the cooling
fluid is directed generally toward polishing wheel 28 to provide
cooling of polishing wheel 28. The cooling fluid further serves to
lubricate the contact point between polishing wheel 28 and
automotive glass sheet 12. Preferably, pump assembly 54 includes a
filtering device (not shown) for removing debris from the cooling
fluid.
[0022] During operation, automotive glass sheet 12 is retained by
retaining device 16 via the plurality of retaining members 24.
According to the present embodiment, automotive glass sheet 12
remains stationary as polishing wheel 28 passes therearound. During
this time, motor 26 rotatably drives polishing wheel 28 via drive
system 51. Simultaneously, moveable support structure 14 carries
polishing wheel assembly 20, chip removal system 22, and cooling
system 52 about automotive glass sheet 12 along a predetermined
path. As can be appreciated, due to the ability of edge polishing
apparatus 10 to accommodate dimensional variations of automotive
glass sheet 12 and/or dimensional variations of polishing wheel 28,
it is not necessary that moveable support structure 14 trace an
exact path relative to automotive glass sheet 12. Alternatively, it
should be understood that polishing wheel assembly 20, chip removal
system 22, and cooling system 52 may remain stationary while
automotive glass sheet 12 is rotated during polishing.
[0023] During the polishing process, polishing wheel 28 remains in
contact with automotive glass sheet 12. However, dimensional
variations in automotive glass sheet 12 and/or polishing wheel 28
produce a resultant force between polishing wheel assembly 20 and
automotive glass sheet 12. This resultant force, in the case where
the portion of automotive glass sheet 12 extends outwardly, forces
polishing wheel 28 and wheel linkage 34 in a direction, generally
indicated by Arrow A. Consequently, intermediate linkage 36 pivots
about motor linkage 32, thereby moving intermediate linkage 36
against the biasing force of spring member 47. However, spring
member 47 is set to a predetermined setting to maintain the
appropriate biasing force within intermediate linkage 36 and, thus,
the appropriate contact pressure between polishing wheel 28 and
automotive glass sheet 12. A similar, but opposite, operation
occurs when a portion of automotive glass sheet 12 extends
inwardly.
[0024] It should be understood, however, that although pressure
sensor 48 may be used to ensure the proper contact pressure between
polishing wheel 28 and automotive glass sheet 12, it is not
required. That is, once polishing wheel assembly 20, namely spring
member 47, is set to maintain the desired contact pressure, further
adjustment is not generally required. Therefore, pressure sensor 48
may be subsequently removed. Moreover, it should be understood that
motor 26, polishing wheel 28, and a direct drive shaft (not shown)
may be used in fixed relationship with each other. In this case,
the entire unit consisting of motor 26, polishing wheel 28, and a
direct drive shaft would be biased in an engaged position against
automotive glass sheet 12. During operation, this unit would be
capable of articulating relative to the edge of automotive glass
sheet 12.
[0025] During the polishing operation, chip removal system 22
removes, contains, or treats glass dust and other debris produced
during polishing. Additionally, chip removal system 22 is
preferably capable of removing, cleaning, and recirculating the
cooling fluid output by cooling system 52. Such filtering may be
accomplished within a filtering device of cooling system 52.
[0026] Referring now to FIG. 2, an edge polishing apparatus,
generally indicated at 100, is provided for maintaining a constant
and consistent polishing pressure upon the edge of an automotive
glass sheet 12 according to a second embodiment of the present
invention. Although it should be readily understood that such
components may be used in conjunction with the present
embodiment.
[0027] Edge polishing apparatus 100 generally includes a moveable
support structure 115, a glass sheet retaining device 116, a
polishing wheel assembly 120, chip removal system 22, and a cooling
system 52.
[0028] Moveable support structure 115 is provided for handling
automotive glass sheet 12 during the polishing procedure. Moveable
support structure 115 is preferably a joint servo robot 122 having
a base structure 124, a first arm linkage 126, and a second arm
linkage 128. An end 130 of first arm linkage 126 is pivotally
coupled to base structure 124 at joint 132. First arm linkage 126
is articulatable about base structure 124 to provide the necessary
degrees of freedom.
[0029] Similarly, an opposing end 134 of first arm linkage 126 is
pivotally coupled to second arm linkage 128 at an end 136 at joint
138. Unlike joint 132, joint 138 may be limited to freedom along a
single plane. However, if additional degrees of freedom are
required, joint 138 may be a ball joint or the like. Glass
retaining device 116 is further coupled to an opposing end 140 of
second arm linkage 128. Glass retaining device 116 may be of
similar construction to glass retaining device 16 or may include a
single main suction member, as shown.
[0030] Joint servo robot 122 includes a plurality of servo motors
(not shown) that actuate first arm linkage 126 and second arm
linkage 128 to position the edge of automotive glass sheet 12 in
contact with polishing wheel assembly 120 according to the
principles of the present invention. To this end, joint servo robot
122 rotates automotive glass sheet 12 such that the entire edge of
automotive glass sheet 12 is polished.
[0031] Polishing wheel assembly 120 generally includes a motor 126
fixedly coupled to a support structure 114 to prevent relative
movement therebetween. Polishing wheel assembly 120 further
includes a polishing wheel 28 coupled to motor 126 through a direct
drive assembly 130.
[0032] Direct drive assembly 130 may be a motor linkage 132
extending from motor 126 pivotally coupled to polishing wheel 28.
In order to ensure proper contact pressure between polishing wheel
28 and the edge of automotive glass sheet 12, motor linkage 132 is
preferably a compliant member that is capable of flexing to
accommodate the dimensional variation of automotive glass sheet 12
and/or dimensional variation of polishing wheel 28 caused by wear.
However, it should be understood that direct drive assembly 130 may
include spring member 47 and adjustment knob 49, as described above
and illustrated in phantom in FIG. 2.
[0033] Polishing wheel 28 is driven through direct drive system
130, which may include a gearing system disposed within the motor
linkage 132. Alternatively, direct drive system 130 may include a
drive shaft that is capable of driving polishing wheel 28.
[0034] During operation, automotive glass sheet 12 is retaining by
retaining device 116. According to the present embodiment,
polishing wheel assembly 120 remains generally stationary as joint
servo robot 122 rotates automotive glass sheet 12 such that the
entire edge of automotive glass sheet 12 is polished by polishing
wheel 28. During this time, motor 126 rotatably drives polishing
wheel 28 via direct drive system 130. As can be appreciated, due to
the ability of edge polishing apparatus 100 to accommodate
dimensional variations of automotive glass sheet 12 or dimensional
variations of polishing wheel 28, it is not necessary that joint
servo robot 122 rotate automotive glass sheet 12 exactly, since
variations in contact pressure are accommodate by compliant motor
linkage 132.
[0035] The description of the invention is merely exemplary in
nature and, thus, variations that do not depart from the gist of
the invention are intended to be within the scope of the invention.
Such variations are not to be regarded as a departure from the
spirit and scope of the invention.
* * * * *