U.S. patent application number 11/055889 was filed with the patent office on 2005-07-28 for sampling cartridge for gas sampling apparatus.
This patent application is currently assigned to Rupprecht & Patashnick Company, Inc.. Invention is credited to Bailey, Adam C., Basch, Lauren R., Cummings, Michael S., Rogers, William E..
Application Number | 20050160839 11/055889 |
Document ID | / |
Family ID | 33309550 |
Filed Date | 2005-07-28 |
United States Patent
Application |
20050160839 |
Kind Code |
A1 |
Rogers, William E. ; et
al. |
July 28, 2005 |
Sampling cartridge for gas sampling apparatus
Abstract
A sampling cartridge for a gas sampling apparatus includes a
shell having a cylindrical wall and a sampling window extending
through the wall. A pair of spools are coaxially and internally
positioned within the shell. The spools are independently rotatable
relative to the shell. A first spool may include multiple interval
sample collectors while the second spool includes a duration sample
collector. Each spool also has a window closing surface which is
positioned adjacent the window whenever an access door of the gas
sampling apparatus is opened. The sampling cartridge may also
include a fully encapsulated section of sample collector material
as a negative control, and an integral RF tag for storing chain of
custody information including personal identification information
of a cartridge replenisher.
Inventors: |
Rogers, William E.; (Troy,
NY) ; Bailey, Adam C.; (Albany, NY) ;
Cummings, Michael S.; (Saratoga, NY) ; Basch, Lauren
R.; (East Greenbush, NY) |
Correspondence
Address: |
HESLIN ROTHENBERG FARLEY & MESITI PC
5 COLUMBIA CIRCLE
ALBANY
NY
12203
US
|
Assignee: |
Rupprecht & Patashnick Company,
Inc.
East Greenbush
NY
|
Family ID: |
33309550 |
Appl. No.: |
11/055889 |
Filed: |
February 11, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11055889 |
Feb 11, 2005 |
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10835721 |
Apr 30, 2004 |
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6898990 |
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10835721 |
Apr 30, 2004 |
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10419535 |
Apr 21, 2003 |
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6769316 |
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10419535 |
Apr 21, 2003 |
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10177749 |
Jun 21, 2002 |
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6867413 |
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Current U.S.
Class: |
73/863.31 ;
73/863.25 |
Current CPC
Class: |
G01N 2001/245 20130101;
G01N 1/24 20130101; G01N 2001/2223 20130101; G01N 1/2208
20130101 |
Class at
Publication: |
073/863.31 ;
073/863.25 |
International
Class: |
G01N 001/22 |
Claims
1-20. (canceled)
21. A sampling cartridge for gas sampling apparatus, comprising: a
cylindrical shell having a sampling window extending through a
cylindrical wall of said shell; and a pair of self-sealing sample
substrate supporting spools inside said shell, each spool having at
least one sample substrate supported at a first circumferential
location of a curved surface of the spool and a window closing
surface at a second circumferential location of said curved
surface; and each spool is self-sealed by rotating its window
closing surface into alignment with said window.
22. The cartridge of claim 21, wherein said shell is
transparent.
23. The cartridge of claim 21, wherein said shell includes a radio
frequency tag for storing chain of custody information.
24. The cartridge of claim 23, wherein said chain of custody
information includes personal identification information of a
cartridge replenisher.
25. The cartridge of claim 21, further including a fully
encapsulated portion of virgin sample substrate material for use as
a negative control.
26. The cartridge of claim 21, wherein a first spool of said pair
includes multiple circumferentially spaced interval sample
substrates, a second spool of said pair includes a single duration
sample substrate, and said first and second spools are
independently rotatable relative to said shell.
27-30. (canceled)
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of commonly
assigned U.S. application Ser. No. 10/177,749, filed Jun. 21, 2002,
the entire contents of which is incorporated herein by
reference.
FIELD OF THE INVENTION
[0002] This invention relates generally to gas samplers, and more
particularly to sampling cartridges for collecting and detecting
particulate in a gas.
BACKGROUND OF THE INVENTION
[0003] Conventional gas samplers for collecting particulate include
a housing having a vacuum pump for drawing gas past a collector
such as a filter paper, a glass fiber filter media, a filter
cassette or an activated carbon cartridge.
[0004] Limitations with such conventional gas samplers for
collecting particulate include the vacuum pump generally producing
a low flow rate of gas to be sampled, the filter becoming clogged,
and the vacuum pump being noisy.
[0005] A high-flow rate, low-noise, gas sampling apparatus which
overcormes the above limitations and may be used for collecting
particulates such as biological, chemical, and radioactive material
from a gas on a collector such as an impaction collector is
disclosed in commonly assigned U.S. patent application Ser. No.
10/177,749. This sampler includes a housing having an inlet and an
outlet, and a fan disposed within the housing for drawing the gas
into the inlet, past the collector for sampling, and exhausting the
gas through the outlet. The sample collector preferably comprises a
foam or porous cloth material of the type described in U.S. Pat.
No. 6,435,043, entitled "Impaction Substrate and Methods of Use",
the entire contents of which is incorporated by reference herein.
The fan is operable to produce a flow of gas through the housing of
greater than about 50 liters per minute, and preferably greater
than about 200 liters per minute, with a noise level emitted from
the apparatus of less than about 60 decibels. The sampler may be
configured as a compact, unobtrusive, portable, light-weight
apparatus for use in various indoor or outdoor locations. It may
also include a sensor for the detection of radioactive material
collected on the collector, and a processor for monitoring the
sampling, and may be linked to a communications network such as the
internet. Related methods for collecting particulate from a gas are
also described in the referenced patent application.
[0006] There is a need to further ensure the integrity of collected
particulate samples.
SUMMARY OF THE INVENTION
[0007] The present invention provides, in a first aspect, a
sampling cartridge for a gas sampling apparatus. The cartridge
includes a shell having a cylindrical wall and a sampling window
extending through the wall. A spool is positioned adjacent the
shell and has a sample collector located at a first circumferential
location and a window closing surface located at a second different
circumferential location. The spool and shell are rotatable
relative to each other such that the sample collector and window
closing surface can be selectively alternatively positioned
adjacent the window for sample collection and cartridge sealing
respectively. The self-sealing feature protects the collected
particulate sample during cartridge removal, handling and
transport.
[0008] The spool is preferably coaxial with and internal to the
shell. The shell may be at least partially transparent to permit
visual confirmation of previous use.
[0009] The spool may have a plurality of sample collectors at
circumferentially spaced locations to permit sampling at different
time intervals. Each of the sample collectors may comprise a foam
or porous cloth material. The sample collector may preferably
comprise a perforated foam material.
[0010] The cartridge may further include a fully encapsulated
segment of the sample collector material as a negative control. The
cartridge may also include memory means for storing chain of
custody information about the cartridge. The chain of custody
information can include personal identification information of a
cartridge replenisher. Preferably, the memory means comprises a
radio frequency tag which is serialized for traceability and
write-protected to ensure single use of the cartridge.
[0011] The cartridge can further include a duration sample
collector exposed through the window and separate from the spool.
The duration sample collector may be mounted at a first
circumferential location on a second spool which is independently
rotatable relative to said shell. The second spool may include a
second window closing surface at a second circumferential position.
The first and second window closing surfaces may be automatically
positioned adjacent the window whenever the cartridge is removed
from the gas sampling apparatus.
[0012] The sampling cartridge may be combined with gas sampling
apparatus having an access door. Preferably the cartridge is
automatically sealed by positioning the window closing surface(s)
adjacent the window, whenever the access door is opened. The gas
sampling apparatus may further include a mandrel for mounting the
cartridge and producing relative rotation between the shell and the
spool(s).
[0013] The present invention provides, in a second aspect, a
sampling cartridge for gas sampling apparatus which includes a
cylindrical shell having a sampling window, and a pair of internal
self-sealing sample substrate spools. Preferably, the shell is
transparent and includes a radio frequency tag for storing chain of
custody information relating to the cartridge. The chain of custody
information may include personal identification information of a
cartridge replenisher.
[0014] The cartridge may further include a fully encapsulated
portion of virgin sample collector substrate material. The first
spool may include multiple circumferentially spaced interval sample
substrates while the second spool may include a single duration
sample substrate. Each spool may further include, a window closing
surface. The first and second spools are independently rotatable
relative to the shell, and each spool is self-sealed by rotating
its window closing surface into alignment with the window.
[0015] The present invention provides, in a third aspect, a method
of collecting a particulate sample with gas sampling apparatus
having an access door. The method includes collecting the sample on
a substrate, automatically sealing the substrate whenever the
access door is opened, and recording chain of custody information
on memory means associated with the substrate. The collection step
may comprise collecting the sample on a substrate of a sampling
cartridge. The sealing step may comprise self-sealing the
cartridge. The recording step may comprise recording the chain of
custody information for the cartridge on a radio frequency tag
integral with the cartridge. The chain of custody information may
include personal identification information of a cartridge
replenisher. Further, the cartridge may incorporate a fully
encapsulated portion of virgin substrate material as a negative
control.
[0016] The present invention assures the integrity of collected
particulate samples by employing a self-sealing sampling cartridge,
automating the sealing of the cartridge upon. opening of the access
door of the gas sampling apparatus, incorporating a fully
encapsulated portion of the virgin substrate material as a negative
control, and storing chain of custody information on a Radio
Frequency (RF) tag integral with the cartridge. These and other
features, advantages and objects of the present invention will be
more fully understood from the following detailed description of
preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The subject matter which is regarded as the invention is
particularly pointed out and distinctly claimed in the concluding
portion of the specification. The invention, however, may best be
understood by reference to the following detailed description of
various embodiments and the accompanying drawings in which:
[0018] FIG. 1 is a front perspective view of the exterior of gas
sampling apparatus in accordance with the present invention;
[0019] FIG. 2 is a front elevational view of the gas sampling
apparatus with an access door opened;
[0020] FIG. 3 is an enlarged perspective view of components of the
gas sampling apparatus, including a sampling cartridge in
accordance with the present invention;
[0021] FIG. 4 is a longitudinal cross-sectional view through the
mounted sampling cartridge of FIG. 3;
[0022] FIG. 5 is a perspective view showing the sampling cartridge
removed from the supporting mandrel;
[0023] FIG. 6 is a perspective view from the mounting end of the
sealed sampling cartridge of the present invention;
[0024] FIG. 7 is a perspective view of the sampling cartridge with
exposed sample collectors;
[0025] FIG. 8 is a simplified exploded view of a multi-interval
sampling cartridge;
[0026] FIG. 9 is a more detailed exploded view of an embodiment of
a multiple interval sampling cartridge;
[0027] FIG. 10 is a partially cut-away perspective view showing the
placement of an encapsulated segment of sample collector material
in the sampling cartridge for use as a negative control; and
[0028] FIG. 11 is a perspective view of a sampling cartridge with
an integral radio frequency tag.
DETAILED DESCRIPTION OF THE INVENTION
[0029] According to the principles of the present invention, gas
sampling apparatus, such as the device described in commonly owned
U.S. patent application Ser. No. 10/177,749, is provided with a
self-sealing sampling cartridge. The cartridge is used to collect
particulate or other material from sampled gas and is automatically
sealed whenever the access door of the gas sampling apparatus is
opened. The cartridge may include multiple interval sample
collectors as well as a duration sample collector. Advantageously,
the cartridge also includes a fully encapsulated segment of sample
collector material to serve as a negative control, and memory
means, e.g. a radio frequency (RF) tag, for storing chain of
custody information, preferably including personal identification
information of a cartridge replenisher. An outer shell of the
cartridge may be at least partially transparent to permit visual
confirmation of previous use of the cartridge. These features
individually and collectively assure the integrity of collected
particulate samples.
[0030] FIG. 1 presents an exterior view of gas sampling apparatus
(10) which may employ the sampling cartridge of the present
invention. Apparatus (10) generally includes a housing (12) having
an inlet (14) connected by sample tube (16) to a top of housing
(12), and an outlet (not shown). Inlet (14) may be any known inlet
which serves to remove relatively large-sized particles from the
gas and directs the sampled gas through tube (16) to a sample
collector mounted on a sampling cartridge within housing (12). For
example, inlet (14) may remove particles with a diameter of 10
micrometers or more from the sample gas.
[0031] Access door (18) may be hingedly mounted at the front of
housing (12) to provide ready access to the components within
housing (12). Access door (18) is preferably provided with a
pick-proof lock (20).
[0032] Housing (12) may be conveniently divided into an upper
section (22) containing the sampling components, and a lower
section (24) containing electronics and communications equipment.
The latter equipment can be used to control the operation of the
sampling components and to provide external communication
capabilities.
[0033] FIG. 2 illustrates the components within the upper section
(22) of housing (12) with the access door (18) opened. Located
within section (22) is a blower or fan (26), sample collection
equipment (28) including sampling cartridge (30), and a status
panel (32).
[0034] High performance blower or fan (26) serves to draw gas
through inlet (14), sample tube (16) and sampling equipment (28) so
that samples of particulate matter may be collected. The fan
produces a flow of gas of greater than about 50 liters per minute,
and preferably greater than 200 liters per minute reducing the time
to obtain a particulate sample for analysis. Fan (26) generates
little noise so that a noise level emitted from the housing is less
than about 60 decibels. To reduce the level of noise from apparatus
(10) further, sound reducing material or insulation may be disposed
on an inner surface of the housing. In addition, a muffler (not
shown) may be disposed aft of the fan to further reduce the level
of noise emitted by apparatus (10). A suitable high-flow rate,
low-noise fan is manufactured and available from Ametek-Rotron of
Saugerties, New York, Model No. MF 501. The use of such a fan also
results in low power consumption. The gas sampling apparatus(10)
may be connected to an AC power supply, or powered by a battery,
and/or may include a back-up battery power supply.
[0035] As most clearly seen in FIG. 3, status panel (32) may
include system status lights (34), communication ports, e.g. a
RS-232 computer port (36) and a removable compact flash memory card
(38). Compact flash memory card (38) is readily available in sizes
from 32 to 256 MB and provides ample capacity to store
second-by-second sensor data and other operating information of the
gas sampling apparatus. The flash memory card also facilitates easy
transfer of data to personal computers or through a network to a
central monitoring station.
[0036] Mounted near status panel (32) is a radio frequency antenna
(40) which, as is more fully described hereinafter, facilitates
communication with an RF tag associated with sampling cartridge
(30). The RF antenna (40) may transfer information to the RF tag,
including chain of custody information for the sampling cartridge.
Gas sampling apparatus (10) may advantageously be provided with the
capability to read/validate personal identification information
from a unique RF tag worn by a cartridge replenisher. The
validation may occur through comparison to internally stored ID
information or confirmation from a central monitoring station
through a communications link. This replenisher identification
information can be transmitted by the radio frequency antenna (40)
for storage on a RF tag associated with a cartridge (30). The gas
sampling apparatus may also broadcast the time and replenisher
information from the cartridge to a central station. Replenisher ID
information may be automatically stored on retrieved or newly
installed cartridges, thus providing a tamper-evident system.
[0037] The particulate sampling equipment (28) includes an
acceleration nozzle or slit(s) (42) sandwiched between sample tube
16 and sampling cartridge (30). As illustrated in FIG. 4, sampling
cartridge (30) is mounted on a split mandrel (44) and inner shaft
(46) in a position such that interval sample collectors (48) and a
duration sample collector (50) on the cartridge are exposed to the
sampled gas stream through slit(s) (42). Each sample collector is
composed of a substrate (52) which serves to collect particulate
from sampled gas that is channeled through nozzle or slit(s) 42 and
impacts upon the collectors. Substrate (52) may be comprised of a
foam or porous cloth material. Exemplary substrate materials
include polyurethane, polyethylene, polypropylene, polyester or
other suitable material. The substrate may be a porous material
about 0.2 millimeters thick or greater. In one embodiment, the
substrate may comprise a polyurethane foam material having a
density of about 0.005 g/cm.sup.3 to about 0.1 g/cm.sup.3.
Particulate with a size of about 1.0 micron and larger may be
collected on such a substrate.
[0038] Advantages of the impact collector comprising a foam or
porous cloth material include permitting a high-flow rate of air to
be sampled without clogging the collector or the slit, reducing
particle bounce, eliminating the need to oil the substrate,
inhibiting an increase in the pressure drop on the substrate as
particles are accumulated on the substrate, concentrating the
collection of particles in the upper portion of the substrate, and
allowing the substrate to be formed from a generally inert
material. While a slit impactor is shown, it will be appreciated
that other shaped openings may be employed. Further, impact
collectors for use in the apparatus of the present invention are
disclosed in U.S. Pat. No. 6,435,043, entitled "Impaction Substrate
and Methods of Use" issued on Aug. 20, 2002.
[0039] A radioactivity sensor (not shown) may be employed to detect
and signal, in real time, the presence of radioactive material in
the gas and/or collected particulate, as described in U.S. patent
application Ser. No. 10/177,794.
[0040] Cartridge (30) is retained on mandrel (44) by spring catches
(54) (FIG. 3). As shown in FIG. 5, these catches disengage
themselves when the cartridge is removed from the mandrel.
[0041] When cartridge (30) is removed, a sampling window (56) of
the cartridge is always sealed with a window closing surface 58, as
more fully described hereinafter. The gas sampling apparatus (10)
is configured such that whenever its access door (18) is opened,
installed cartridge (30) is automatically sealed. The sealing
operation is described below.
[0042] FIG. 6 illustrates sampling cartridge (30) with its window
(56) sealed by window closing surface (58). Cartridge (30) is
preferably always sealed during handling and transport by a
cartridge replenisher. Gas sampling apparatus (10) opens the
cartridge after the cartridge is mounted in the housing and the
access door is locked. The gas sampling apparatus re-seals the
cartridge whenever the door is unlocked and opened.
[0043] Referring still to FIG. 6, sampling cartridge (30) has a
cylindrical shell or casing (60) completely closed at one end by an
end cap (62). At the other end of shell (60) is a slotted ring (64)
with an opening (66) for receiving mandrel (44). Ring (64) includes
a pair of tabs (68) which engage spring catches (54) to retain
cartridge (30) on the mandrel. Ring (64) also incorporates a pair
of ears (70) which together with another set of ears (72) at the
other end of the cartridge engage nozzle (42). Ring (64) also has a
slot (74) for spool engagement keys. Finger tabs (76) are provided
at the outer end of cartridge (30) to facilitate removal of the
cartridge for replenishment.
[0044] FIG. 7 shows sampling cartridge (30) in its sam ling or open
state. In this state, interval sample collectors (48) and duration
sample collector (50) are exposed to the sample gas stream through
window (56). As illustrated, interval sample collectors (48) and
duration sample collector (50) may be formed in pre-cut and/or
pre-perforated segments.
[0045] Referring now to FIG. 8, in a preferred embodiment, sampling
cartridge 30 includes a pair of independently rotatable inner
spools (78) and (80) coaxial with and internal to shell (60). First
or interval spool (78) may include multiple sample collectors (48)
circumferentially spaced around the spool for sampling the gas
during different predetermined intervals (time resolved intervals).
Spool (78) also includes a window closing surface (58) at a
predetermined circumferential location. Spool (78) is rotated by
mandrel (44) under control of suitable drive means to expose
different sample collectors (48) during sampling, and is
automatically rotated to place window closing surface (58) adjacent
window (56) to seal the cartridge whenever the access door of the
gas sampling apparatus is opened. The processor or controller (not
shown) of the apparatus can detect opening of the access door
through a suitable switch or sensor, and causes the mandrel drive
means to seal the cartridge in response thereto.
[0046] The second or duration spool (80) includes a duration sample
collector (50) which can be exposed to the sampling gas through
window (56) of shell (60) throughout the sampling period (long
duration sampling). Like spool (78), duration spool (80) includes a
window closing surface (58') which may be automatically rotated to
a position adjacent window (56) for sealing the cartridge whenever
the access door of the gas sampling apparatus is opened. Since
sample collectors (48) and (50) are contained in individual pockets
(81) of the respective spools, when window closing surfaces (58)
and (58') are positioned adjacent window (56), the sample
collectors and any collected particulate are completed sealed off.
Cartridge (60) is thus self-sealing. Duration spool (80) may also
be provided with a pocket for receiving a fully encapsulated
segment (82) of sample collector material which may serve as a
negative control.
[0047] In one practical implementation, as shown in FIG. 9, the
outer shell may be formed in two parts (60a), (60b) and each of the
independently rotatable spools may be formed in two parts (78a),
(78b) and (80a), (80b), respectively. Interval spool (78) may
contain eight circumferentially spaced interval sample collectors
(48) while duration spool (80) contains a single duration sample
collector (50). Each sample collector may be pre-preforated in a
longitudinal direction into multiple, e.g. four parts and also
pre-perforated at a desired depth, e.g. 0.090 inches. Such
pre-perforation allows for optimal sample extraction for subsequent
analysis.
[0048] The outer shell and internal spools, as well as the end
plate and end ring may be manufactured in a variety of different
known ways, for example, molded, and may be made of any suitable
material, e.g. plastic. The cartridge may have a size approximately
2 inch diameter by 2.75 inches long, or other sizes. Outer shell
(60) is preferably at least partially transparent to permit visual
confirmation of previous use of the cartridge.
[0049] The number, shape, type and location of the sample
collectors in spools (78) and (80) may vary from that shown in the
illustrative embodiment. For example, interval spool (78) may for
certain applications include just a single interval sample
collector (48).
[0050] The incorporation of a fully encapsulated segment of
substrate material as a negative control in the sampling cartridge
(30) is illustrated in FIG. 10. As shown, a portion or segment (82)
of virgin sampling substrate (52) used to form sample collectors
(48) and (50), is placed in a vial (84) and sealed therein with a
cap (86). Vial (84) may then be placed in a dedicated pocket (88)
formed in duration spool (80). For clarity of illustration,
cartridge (30) is shown in FIG. 10 with the half (60a) of shell
(60) removed. The fully encapsulated substrate material (82) may be
used to verify substrate material purity, e.g. if a biohazard test
of collected particulate is positive. Vial (84) may be removed from
cartridge (30) by rotating duration spool (80) so that pocket (88)
is aligned with window (56). Vial (84) can then be removed through
the sampling window without opening cartridge (30).
[0051] Data storage or memory means may be associated with the
sampling cartridge. As shown in FIG. 11, a radio frequency (RF) tag
(90) may be integrally formed with the left part (60b) of the shell
(60) of sampling cartridge (30). Such RF tags are known and have in
the past been used for product identification purposes. In the
present invention, an RF tag (90) integral with the cartridge (30)
is not only serialized for unique traceability but is also used to
store chain of custody information for the associated cartridge. As
earlier described, such chain of custody information may include
personal identification information of a cartridge replenisher.
Preferably, data recorded on the RF tag is write-protected to
ensure single use of the sampling cartridge. Once sampling is
complete, sampling cartridge (30) is removed from gas sampling
apparatus (10) in sealed state, and may be placed in sealed plastic
bags for transport to an analysis station. The RF tags permit
individual or multiple sampling cartridges to be read through the
transport bags. The RF tags also provide for automatic data
recording and reading.
[0052] The integrity of the collected samples and the sampling
process is assured, by the present invention, through the provision
of the self-sealing sampling cartridge, the automatic sealing of
the cartridge whenever the access door of the gas sampling
apparatus is opened and the incorporation of the negative control
material within the cartridge. The use of two independently
rotatable spools within the cartridge allows sampling flexibility.
The integral RF tag facilitates storage of chain of custody
information including personal identification information relating
to the cartridge replenisher. These and the other unique features
of the present invention provide for a significantly improved gas
sampling apparatus and method which are uniquely suited for wide
application and secure operation.
[0053] While various embodiments of the present invention have been
illustrated and described, it will be appreciated by those skilled
in the art that many modifications and changes may be made
thereunto without departing from the spirit and scope of the
invention.
* * * * *