U.S. patent application number 10/366592 was filed with the patent office on 2003-09-18 for bendable rolling conveyor guide.
Invention is credited to Ledingham, Stuart J..
Application Number | 20030173194 10/366592 |
Document ID | / |
Family ID | 24837665 |
Filed Date | 2003-09-18 |
United States Patent
Application |
20030173194 |
Kind Code |
A1 |
Ledingham, Stuart J. |
September 18, 2003 |
Bendable rolling conveyor guide
Abstract
A readily bendable rolling conveyor guide is provided. The guide
includes axle-positioning members having notches. The
axle-positioning members slidably engage channels mounted to a
structural support member. A plurality of axles carrying rotatable
elements and spacers are disposed between the axle-positioning
members. Due to the notches in the axle-positioning members and the
unique cross-section of the exterior of the channels, the assembled
guide may be bent at small radii without causing distortion of the
channels or interference between the axle-positioning members and
the channels.
Inventors: |
Ledingham, Stuart J.; (Coto
de Caza, CA) |
Correspondence
Address: |
KNOBBE MARTENS OLSON & BEAR LLP
2040 MAIN STREET
FOURTEENTH FLOOR
IRVINE
CA
92614
US
|
Family ID: |
24837665 |
Appl. No.: |
10/366592 |
Filed: |
February 11, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10366592 |
Feb 11, 2003 |
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09706460 |
Nov 3, 2000 |
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6516933 |
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Current U.S.
Class: |
198/860.1 |
Current CPC
Class: |
B65G 21/2054
20130101 |
Class at
Publication: |
198/860.1 |
International
Class: |
B65G 021/00 |
Claims
What is claimed is:
1. An apparatus for guiding articles moving on a conveyor
comprising: an elongated first axle-positioning member and an
elongated second axle-positioning member spaced from the first
axle-positioning member; one or more first axles extending between
the axle-positioning members with one end of each of said axles
being formed integral with said first axle-positioning member and
the other end of each of said axles being received in a socket
formed in the second axle-positioning member; and one or more
rotatable elements mounted on each of said axles to be engaged by
articles moving on a conveyor.
2. The apparatus of claim 1, wherein said second axle-positioning
member has one or more second axles having one end formed integral
with the second axle-positioning member and with the other end of
the second axles extending into sockets formed in the first
axle-positioning member, and one or more rotatable elements mounted
on the second axles.
3. The apparatus of claim 2, wherein the first axles fit between
the second axles.
4. The apparatus of claim 1, including spacers positioned on said
axles so that rotatable elements on one axle are vertically offset
with respect to the rotatable elements on adjacent axles.
5. The apparatus of claim 4, wherein the spacers are formed
integral with at least one of said axle-positioning members.
6. The apparatus of claim 1, wherein said axle other ends or said
sockets are tapered to facilitate the entry of the axles into the
sockets.
7. The apparatus of claim 1, including first and second guide rails
having channels to receive said axle-positioning members in a
manner to maintain the axles within the sockets.
8. The apparatus of claim 7, wherein said rails and said
axle-positioning members are rigid but bendable so that they may be
bent into a curved configuration.
9. The apparatus of claim 8, wherein said axle-positioning members
have notched edges which facilitate curving of the axle-positioning
members.
10. The apparatus of claim 9, wherein said first and second guide
rails have a surface that includes a V-shaped protrusion along the
outside of the rails.
11. The apparatus of claim 1, wherein said axle-positioning members
are rigid but bendable so that they may be bent into a curved
configuration.
12. The apparatus of claim 11, wherein said axle-positioning
members have notched edges which facilitate curving of the
axle-positioning members.
13. An apparatus for guiding articles moving on a conveyor
comprising: an elongated first axle-positioning member and an
elongated second axle-positioning member spaced from the first
axle-positioning member; one or more spacers, with each of said
spacers being formed integral with one of said axle-positioning
members; one or more sockets formed in each of the axle-positioning
members; one or more axles extending between the axle-positioning
members; and one or more rotatable elements mounted on each of said
axles to be engaged by articles moving on a conveyor.
14. The apparatus of claim 13, wherein said axles are tapered at
either or both of a first end and a second end, or said sockets are
tapered to facilitate the entry of the axles into the sockets.
15. The apparatus of claim 13, including first and second guide
rails having channels to receive said axle-positioning members in a
manner to maintain the axles within the sockets.
16. The apparatus of claim 15, wherein said rails and said
axle-positioning members are rigid but bendable so that they may be
bent into a curved configuration.
17. The apparatus of claim 16, wherein said axle-positioning
members have notched edges which facilitate curving of the
axle-positioning members.
18. The apparatus of claim 17, wherein said first and second guide
rails have a surface that includes a V-shaped protrusion along the
outside of the rails.
19. An apparatus for guiding articles moving on a conveyor
comprising: a pair of spaced elongated axle-positioning members
having notched edges; a plurality of axles extending between said
axle-positioning members; and one or more rotatable elements
mounted on each of said axles, said notched edges of said
axle-positioning members being configured to locate one notch on
each edge between each axle, the notches facilitating curving of
the axle-positioning members about an axis that is perpendicular to
their longitudinal axis.
20. The apparatus of claim 19, including a pair of spaced,
elongated rails each having a channel for respectively receiving
one of the axle-positioning members.
21. The apparatus of claim 20, wherein said guide rails have a
section that includes a V-shaped protrusion along the outside of
the rails.
22. A method of assembling a rolling conveyor guide comprising the
steps of: providing an axle-positioning member having integral
formed axles, wherein the axles are oriented upward; placing an
appropriate number of rotatable elements upon the axles; securing a
second axle-positioning member to the free ends of the axles; and
slidably inserting the assembled axle-positioning members and
rotatable elements into a support structure, wherein the support
structure has spaced channels adapted to receive the
axle-positioning members.
23. The method of claim 22, wherein the second axle-positioning
member is horizontally offset from the first axle-positioning
member, such that the ends of the second axle-positioning member do
not directly oppose the ends of the first axle-positioning
member.
24. The method of claim 22, further comprising the step of bending
the support structure and axle-positioning members.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to guides for installation on opposite
sides of a container transporting conveyor system. More
specifically, the invention relates to guides that are adapted for
installation along both curved and straight sections of the
conveyor system.
[0003] 2. Description of the Related Art
[0004] Guides mounted on opposite sides of conveying systems are
used in a variety of places in industrial installations. For
example, they are used for combining (channeling a wide procession
of conveyed articles in a disorderly array into a single file),
forcing articles around bends in the conveying system, or simply
preventing articles from falling off the side of the conveyor.
Generally, there is at least one guide mounted on each side of the
conveyor.
[0005] Guides may either be fixed or rolling, depending upon the
nature of the guide surface that contacts the conveyed articles.
Fixed guides provide a smooth surface for articles to contact,
while rolling guides provide rotatable elements mounted upon
vertical axles. Guides of both types provide a low friction guiding
surface for a large variety of individual containers including
glass, metal, plastic and paperboard, and packages like cardboard
boxes, and plastic wrapped bundles or trays. Excess friction in any
of these applications can cause line stoppage, package jamming and
possible damage, product spillage or skewed orientation.
[0006] In powered conveyor applications especially, fixed guides
generally provide too much friction to be useful, especially when a
container or package must be guided around a turn or through a
transfer from one conveyor to another. Rolling guides have been
found to be an excellent solution to these problems. In some curved
sections of conveyors, there is only a rolling guide on one side of
the conveyor, with a fixed guide on the other side. Where only one
rolling guide is used, the rolling guide is usually mounted on the
outside, or larger radius, of the curve.
[0007] Rolling guides are often constructed in a similar manner. A
rolling member is positioned on a shaft or axle and contacts the
product/package surface. Sizes of rolling members, and heights of
rolling guides, vary. Guides can be from one inch with one member
to ten inches with fifteen-plus members. Rolling members can
interlock (nest) or stand adjacent. A dense interlocked pattern is
preferred, because the interlocking members minimize gaps that tend
to catch passing articles. The axles are in turn connected to a
structural supporting member by means of an axle-positioning
plastic cap. Aluminum extrusions, bars of steel or aluminum and
formed sections of sheet metal are the most common materials for
the supporting member.
[0008] For economic reasons, guides are generally manufactured in
standard lengths. However, applications for guides often require
unique bead lengths. Therefore, either each length must be amenable
to being cut and/or bent by the purchaser to conform to each
application, or the purchaser must special order the specific
lengths and radii of guides needed, which is typically a more
expensive option.
[0009] Examples of rolling guides are shown in U.S. Pat. Nos.
3,934,706, 4,962,843 and 5,143,200, and VALU GUIDE Model #684. Each
of these guides generally comprises an upper and a lower frame
member that are adapted to be mounted alongside and parallel to the
conveyor. U.S. Pat. No. 4,962,843 comprises a plurality of
vertically stacked frame members. A plurality of axles are disposed
between the frame members, usually with the longitudinal axis of
each axle oriented perpendicularly to the conveying surface.
Rotatably attached to the axles are beads, which are generally
spherical, or rollers, which are generally cylindrical with
protruding flanges that are either round or polygonal.
[0010] This guide configuration is particularly useful for
combining, where each guide is straight. However, none of these
guides are easily bent after they have been assembled. Bending
these guides often results in radical deformation of the supporting
structure and even failure. Therefore, none of these guides are
well suited for use in curved sections of a conveying system unless
they are custom manufactured to meet a particular customer's
need.
[0011] Two examples of guides that are more easily bent by the
purchaser are the Marbett Model #580 and 581, and the System Plast
device. Each length of these guides comprises multiple short
sections of frame members that are all flexibly attached to one
another by means of plastic hinges. The back side of each section
contains a channel that is adapted to be slidably attached to a
bent mounting strip. These designs have some major drawbacks,
however. First, the minimum bending radii are rather high
(approximately 13" for an internal curve, and 15" for an external
curve for the Marbett, and approximately 18" for an internal curve,
and 24" for an external curve for the System Plast). A plant layout
requiring tighter radii would not be able to use these guides.
Second, because the device only bends between sections, and each
section contains four axles, it does not provide an entirely smooth
curve. The transition points between sections have a tendency to
catch passing articles on the conveyor, leading to jamming.
[0012] The design of all of the above-mentioned guides also makes
them more expensive to manufacture. The axles must first be
inserted into an axle-positioning member. After the rotatable
elements have been installed, every single axle must be lined up
properly before the other axle-positioning member can be secured to
the other end of the axles. This is a very tedious process that is
difficult to automate.
[0013] A guide that is easily and cheaply manufactured, easily bent
by the purchaser, is capable of being bent to small radii, and that
doesn't have a tendency to cause conveyed articles to jam would be
of great benefit in any industry that uses conveyors.
SUMMARY OF THE INVENTION
[0014] The bendable conveyor guide of this invention has several
features, no single one of which is solely responsible for its
desirable attributes. Without limiting the scope of this invention
as expressed by the claims that follow, its more prominent features
will now be discussed briefly. After considering this discussion,
and particularly after reading the section entitled "Detailed
Description of the Preferred Embodiments," one will understand how
the features of this invention provide advantages, which include
ease of assembly and ability to be bent by the purchaser.
[0015] The invention provides a rolling conveyor guide that is easy
to bend, and is thus readily adaptable for use in any conveyor
layout. The invention includes any number of axles disposed between
a pair of chain-like axle-positioning members. The axles serve as
mounting points for rotatable elements such as rollers or beads.
The axles and/or spacers may be molded integrally with the
axle-positioning members. A structural support member is provided
having two channels in which the axle-positioning members slidably
engage. The axle-positioning members are rigid but readily bendable
due to evenly spaced notches cut in the edges of the
axle-positioning member. The shape of the notches ensures that the
axle-positioning members will not interfere with the interior walls
of the channels when the entire assembly is bent. Theoretical radii
as small as 5" may be obtained.
BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] The preferred embodiments of this invention, illustrating
its features, will now be discussed in detail. These embodiments
depict the novel and non-obvious bendable conveyor guide of this
invention shown in the accompanying drawings, which are for
illustrative purposes only. These drawings include the following
figures, with like numerals indicating like parts:
[0017] FIG. 1 is a perspective view of a preferred embodiment of
the bendable conveyor guide of the present invention.
[0018] FIG. 2 is an exploded perspective view of a preferred
embodiment of the bendable conveyor guide of the present invention,
illustrating one preferred bead arrangement.
[0019] FIG. 3 is an exploded perspective view of a preferred
embodiment of the bendable conveyor guide of the present invention,
illustrating another preferred bead arrangement.
[0020] FIGS. 4A-4D are front, rear and side views of the channel
member of the present invention.
[0021] FIGS. 5A-5B are front, side and top views of a preferred
embodiment of the axle-positioning member of the present
invention.
[0022] FIGS. 6A-6B are front, side and top views of another
preferred embodiment of the axle-positioning member of the present
invention.
[0023] FIGS. 7A-7C are detail views of the notches in the
axle-positioning member, illustrating the advantages of a preferred
design.
[0024] FIG. 8 is a perspective view of a preferred bending
apparatus of the present invention.
[0025] FIG. 9 is a side view of a preferred bending apparatus of
the present invention, illustrating the advantages of the
intersecting V design.
[0026] FIG. 10 is a perspective view of an alternative embodiment
of the axle-positioning member of the present invention,
illustrating the bi-directional, non-chamfered axle design.
[0027] FIG. 11 is a perspective view of an alternative embodiment
of the axle-positioning member of the present invention,
illustrating the unidirectional, non-chamfered axle design.
[0028] FIG. 12 is a perspective view of the bendable conveyor guide
of the present invention disposed along a conveyor transfer.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] FIG. 1 illustrates a length of the fully assembled bendable
conveyor guide 20 of the present invention, the individual
components of which can be seen in FIGS. 2-6. The guide 20 includes
an elongate structural support member 22, shown in detail in FIG.
4. This member 22 has a generally U-shaped cross-section, with two
equal length extension arms 24 connected by a span 26. The support
member 22 is adapted to be mounted on an appropriate surface
alongside the conveyor by means of a channel 28 running along the
length of the back surface 30 of the support member 22. The channel
28 is adapted to slidably engage a support surface, such as a strip
of material, or a fastening member, such as a bolt head.
[0030] Each extension arm 24 preferably includes a generally
U-shaped channel 32 in spaced relationship with the span 26, with
the open sides of each channel 32 facing one another. Each channel
32 has oppositely disposed V-shaped grooves 34 that are adapted to
slidably engage an axle-positioning member 36.
[0031] The axle-positioning member 36 shown in FIGS. 2, 3, 5A and
5B, 6A and 6B includes two oppositely disposed chain-like strips,
each having a cross-section that is adapted to fit snugly within,
and be retained by, the channel 32 of the extension arm 24. Each
strip is divided into individual links 38 by uniformly spaced
notches 40 along the length of the strip. Although the figures show
a length of the axle-positioning member 36 having seven links, it
will be understood by one of skill in the art that this member 36
and the support structure 22 in which it is housed could be
manufactured in any of a variety of lengths having any number of
axles 42.
[0032] In one preferred embodiment, each link 38 of one strip has
an integrally formed elongate axle 42 extending from the center of
the surface facing the other strip, and each link 38 of the other
strip has a central socket 44 adapted to receive the end of an axle
42. Each axle 42 is generally cylindrical and adapted to receive at
least one rotatable element 46, such as a bead or roller. In one
preferred embodiment, the ends of each axle 42 include a chamfer 48
that facilitates insertion of the axle 42 end into the socket 44 by
eliminating the need for all axles 42 to align exactly with all
sockets 44 at the same time. The length of each axle 42 is variable
depending on the number of rotatable elements 46 that are to be
installed on each one.
[0033] The rotatable element 46 on each axle 42 may stand adjacent
to the rotatable element 46 on the neighboring axles 42, or they
may be offset so that they interlock. The interlocked configuration
can be seen in FIGS. 2 and 3. An interlocked pattern is preferred,
because it minimizes many of the gaps between elements 46 that tend
to trap conveyed articles as they pass. If the elements 46 are to
be offset, at least every other axle 42 must include one or more
spacers 50 (FIG. 5B). In order to make assembly of the bendable
conveyor guide 20 easier, spacers 50 may be formed integrally with
some or all of the links 38 of each strip. In one preferred
embodiment, every other link 38 has an integrally formed spacer 50
attached to the surface facing the other strip. Depending upon the
rotatable element 46 arrangement desired, spacer 50 orientation may
either be opposing, as in FIG. 3, or alternating, as in FIG. 2.
Also, each strip may be formed with alternating axles 42 of
different heights, as in FIGS. 5B and 6B, depending on how the
spacers 50 and rotatable elements 46 are to be arranged.
[0034] It will be understood by one of skill in the art that it is
not necessary to mold spacers 50 integrally with the links 38, but
that doing so can make assembly of the entire device 20 easier and
cheaper.
[0035] The axle-positioning member 36 can be made of any material
suitable to withstand the anticipated loads upon the conveyor guide
20 and to have a low-friction compatibility with the rotatable
elements 46, which are most often acetal or polypropylene or nylon.
Metals provide greater strength than plastics, but plastics are
easier to mold. Thus, if metals must be used, the economic
advantages associated with integrally molding the spacers 50 and
the links 38 may be lost. When acetal rotatable elements 46 are
used and expected loads are relatively light, the member 36 may be
manufactured from a material such as PBT which is preferred for
reduced friction and structural strength.
[0036] FIGS. 7A-7C illustrate the design of the notches 40 between
the links 38 of each strip. In FIG. 7A, the links 38 have square
corners 52. These comers 52 interfere with the side walls 54 of the
extension arm channel 32 when the entire assembly 20 is bent. The
interference leads to two problems. First, it makes it difficult,
if not impossible, to remove the axle-positioning members 36 from
the channel 32.
[0037] Second, it places strain on the links 38 that can lead to
upsetting the orientation of the axles 42. Because the rotatable
members 46 are preferably in close proximity to one another, any
upsetting of the axle 42 orientation can cause the rotatable
members 46 to interfere with one another. This interference can
compromise the ability of the guide 20 to provide a low-friction
surface.
[0038] In FIG. 7B, the corners 56 have been rounded somewhat. The
rounding lessens the interference somewhat, but it is still a
potential problem. FIG. 7C illustrates a more preferred shape for
the links 38. Links 38 of this shape largely eliminate interference
with the channel 32 and greatly facilitate bending of the assembled
guide 20. Theoretical radii as small as 5" can be accomplished
without undesirable distortion of the channel 32 or the
axle-positioning member 36.
[0039] The process of making a preferred embodiment of the rolling
guide 20 of the present invention is most easily understood with
reference to FIGS. 5A-5B and 6A-6B. FIGS. 5A and 6A represent one
strip of the axle-positioning member, while FIGS. 5B and 6B
represent the second strip, which mates with the first strip to
form the complete axle-positioning member.
[0040] The manufacturer begins with the strip 35 having integral
axles 42, pictured in FIGS. 5B and 6B and referred to as the lower
strip 35. It will be understood by one of skill in the art that the
axle 42 lengths may be varied in any manner to suit a particular
application. They may be of uniform height, they may alternate in
height, as in FIGS. 5B and 6B, or they may increase steadily in
height from one end of the strip 35 to the other.
[0041] The lower strip 35 is positioned so that the axles 42 are
oriented upward. The appropriate number of rotatable elements 46
are then placed upon the axles 42. As long as the axles 42 are
oriented upward, gravity will hold the rotatable elements 46 in
place.
[0042] Because the preferred arrangement of rotatable elements 46
is an interlocked pattern, as shown in FIGS. 2 and 3, the axles 42
must receive the rotatable elements 46 in a proper sequence to
avoid any rotatable elements 46 blocking the passage of neighboring
rotatable elements 46 as they move down the axle 42 to their
resting positions. One such method is to first place one rotatable
element 46 on each axle 42 having no spacer 50, and then place one
rotatable element 46 on each axle 42 having a spacer 50, continuing
with this pattern until all rotatable elements 46 have been
installed.
[0043] Once all rotatable elements 46 have been installed, the
upper strip 37 is placed atop the ends of the axles 42. To aid
insertion of the axle 42 ends into the sockets 44, a preferred
embodiment provides a chamfer 48 on the ends of the axles 42 and/or
within the sockets 44. If a number of lengths of strips are to abut
one another, the transitions between adjacent strips can be
smoothed by offsetting the upper strip 37. In this way, no seam in
the upper strip 37 would be directly opposite a seam in the lower
strip 35. This arrangement can help to minimize gaps between axles
42.
[0044] Alternatively, the ends of each strip can be provided with
mating apparatus so that they can be securely attached to one
another. For example, each strip could include male and female
connecting portions on opposite ends.
[0045] Once the upper strip 37 is in place, the entire assembly is
inserted slidably into the channels 32 of the support member 22. If
a bent length of guide 20 is desired, the assembled guide 20 is
bent in a manner described below.
[0046] FIGS. 8 and 9 illustrate one preferred method of bending the
assembled device 20 using a three-roll bender. The bender includes
an adjustable roll 58 and two stationary rolls 60. The
cross-sections of each roll 58, 60 are shaped as the mirror image
the surface of the support member 22 that the roll engages, as
illustrated in FIG. 9. The adjustable roll 58 thus includes a
center flange 62 to fit between the legs of the channel 28 on the
back surface 30 of the support member 22, and upper 64 and lower 66
tapered sections to match the corresponding tapered sections on the
back surface 30 of the support member 22. The stationary roll 60
includes upper 68 and lower 70 V-shaped surfaces to engage the
corresponding upper 72 and lower 74 V-shaped surfaces on the front
surface of the support member 22. The V-shaped surfaces on the
front surface of the support member 22 are illustrated in detail in
FIG. 4C.
[0047] These unique cross-sections on both the support member 22
and the bending rolls 68, 70 are another aspect of the invention
that facilitates bending. A common problem when bending rolling
guides is distortion of the channel 32 in which the
axle-positioning member 36 fits. Such distortion can cause axle 42
misalignment and the problems associated therewith. The V-shaped
surfaces 72, 74 on the exterior of the channel 32 together with the
corresponding V-shaped surfaces 68, 70 of the roller 60 largely
eliminate channel 32 distortion. The axles 42 thus remain aligned
within the bent guide 20. Of course, as will be understood by those
of skill in the art, the surfaces 72, 74 on the member 22 may be of
any configuration to align with the surfaces 68, 70 of the roller
60 to facilitate predictable and uniform bending.
[0048] The design of the rolling guide 20 of the present invention
makes bending so easy that it may be performed by the guide 20
purchaser. Three-roll benders of the type used to bend these guides
20 are inexpensive to purchase or rent, and require little
expertise to use properly. Thus, the guides 20 of the present
invention can be manufactured in standard straight lengths, keeping
costs down, and bent by the purchaser to suit a particular
application. Alternatively, the purchaser can request the guides 20
to be bent by the manufacturer prior to delivery. Because the
guides 20 are so easy to bend, bending by the manufacturer does not
significantly raise the cost of the guides 20.
[0049] FIGS. 8 and 9 illustrate the proper configuration to form an
interior bend. Most curved conveyor sections require a guide 20 on
both the interior and exterior side of the curve. Thus, to form an
exterior bend, the adjustable roll 58 in FIG. 8 is exchanged for
one having the same cross-section as the stationary roll 60 in FIG.
8, and vice versa. The assembled guide 20 is passed through the
rolls 58, 60 in the opposite orientation as in FIG. 8, so that the
rotatable element 46 surface faces the new adjustable roll 58.
[0050] FIGS. 10 and 11 illustrate two alternate embodiments of the
axle-positioning member 36 of the present invention. In FIG. 10,
the strips of the axle-positioning member 36 are formed such that
every other link 38 has an integral axle 42. In FIG. 11, the ends
of the axles 42 are formed without a chamfer.
[0051] FIG. 12 illustrates the bendable conveyor guide 20 of the
present invention disposed in a transfer operation. Conveyed
articles typically need to be transferred from one conveyor to
another as they travel through an industrial installation. Rolling
conveyor guides 20, such as the one disclosed here, are typically
needed in these areas to prevent problems such as jamming or
tipping of articles.
[0052] The above presents a description of the best mode
contemplated for carrying out the present invention, and of the
manner and process of making and using it, in such full, clear,
concise, and exact terms as to enable any person skilled in the art
to which it pertains to make and use this invention. This invention
is, however, susceptible to modifications and alternate
constructions from that discussed above which are fully equivalent.
Consequently, it is not the intention to limit this invention to
the particular embodiments disclosed. On the contrary, the
intention is to cover all modifications and alternate constructions
coming within the spirit and scope of the invention as generally
expressed by the following claims, which particularly point out and
distinctly claim the subject matter of the invention.
* * * * *