MCCAMBRIDGE JAMES E (US)
ARNDT STEVE (US)
MILLER DENNIS L (US)
STRIPLING TERRI (US)
KARKER JEFF (US)
DRUGRISK SOLUTIONS LLC (US)
MELTON SCOTT A (US)
MCCAMBRIDGE JAMES E (US)
ARNDT STEVE (US)
MILLER DENNIS L (US)
STRIPLING TERRI (US)
KARKER JEFF (US)
US4828395A |
WHAT IS CLAIMED IS:
1. An apparatus for comminuting biological specimens,
comprising:
a receiving component (28) provided with a drive source (30);
at least one sample retainer (26) configured for
accommodating at least one biological specimen and constructed and
arranged for engagement in said receiving component;
said sample retainer (26) including a first component (80)
configured for receiving a specimen prior to comminution and a second
component (96) for receiving the specimen after comminution;
said sample retainer being insertable into said receiving
component as a single piece.
2. The apparatus of claim 1 wherein said sample retainer
includes at least one first comminution surface (86).
3. The apparatus of claim 2 wherein said sample retainer
(26) further includes a ram element (112) having at least one second
comminution surface (114) and being engageable with said first component. 4. The apparatus of claim 3 wherein said drive source (30)
is configured for moving said first component (80) relative to said ram
element (112).
5. The apparatus of claim 4 further including at least one
ram key (64) configured for securing said ram element (112) relative to
movement of said first component (80), and for exerting a biasing force
against said ram element for urging said ram element against said first
component.
6. The apparatus of claim 1 further including a sample
collector (72) engageable upon said second component.
1
7. The apparatus of claim 6 further including at least one
pocket (68) for supporting said sample collector (72) upon insertion into said
receiving component (28).
8. The apparatus of claim 6 wherein said sample collector
(72) is insertable into said receiving component (28) with said sample
retainer (26) and a ram element 112 as a unit. 9. The apparatus of claim 1 wherein said drive source (30)
is configured for moving at least two of said sample retainers
simultaneously.
10. The apparatus of claim 9 wherein said drive source
(30) includes at least one drive collar (38) configured for rotating a
corresponding one of said sample retainers (26) and being driven by said
drive source.
11. The apparatus of claim 10 wherein said drive source
(30) is a belt and pulley system (34, 36).
12. A machine for comminuting multiple biological
specimens, each specimen being provided in a sample retainer (26)
including a first component (80) configured for receiving a specimen prior
to comminution, a second component (96) for receiving the specimen after
comminution, and a ram element (112), said machine comprising;
a drive source (30);
a plurality of drive collars (38) configured for being driven by
said drive source, each said drive collar configured for receiving a
corresponding sample retainer (26); and
a plurality of ram keys (62) each corresponding to one of said drive collars and configured for exerting a biasing force on a corresponding
ram element (112) for causing comminution of a sample in the sample
retainer.
13. The machine of claim 12 wherein each said ram key
(62) is configured for preventing the ram element from moving relative to
the sample retainer.
14. The machine of claim 12 wherein said sample retainers
include a sample collector (72), and said machine is provided with at least
one pocket (68) for receiving and supporting said sample collector.
15. The machine of claim 12 wherein said drive source (30)
is configured for moving said drive collars (38) simultaneously.
16. The machine of claim 12 further including a lid (14)
configured for receiving said ram keys (62) and for selectively disengaging
said ram keys from operational relationship with said drive collars (38).
17. The machine of claim 12 further including a vibration
generating mechanism (164) for transmitting vibrations to the sample
retainer. 18. The machine of claim 12 further including an apparatus
(170, 172, 174) for exerting pressure on said ram keys (62) for ultimately
pressurizing said ram elements, wherein said exerted pressure is one of
intermittent and constant in duration, and/or variable in force.
19. A sample retainer (26) for use with a machine (10) for
comminuting biological specimens, said machine including a drive source
(30), a plurality of drive collars (38) and a like plurality of ram keys (62),
said sample retainer comprising:
a cup (80);
a funnel (96) joinable to said cup;
at least a first comminution surface (86) associated with at
least one of said cup (80) and said funnel (96); and
upon joining, said cup and said funnel being insertable into the
machine as a unit.
20. The sample retainer of claim 19 further including a ram
(112) engageable with said cup (80) and having a second comminution
surface (114), said ram being insertable with said funnel into the machine as
a unit.
21. The sample retainer of claim 20 wherein said ram has at
least one key formation (124) for engaging a corresponding ram key (62). 22. The sample retainer of claim 20 wherein at least one of
said first and second comminution surfaces (86, 114) has a plurality of
comminution bosses (88) spaced at approximately .064 inch center-to-
center.
23. The sample retainer of claim 20 wherein said ram has a
closed end (118) with a depending projection (119) creating a bulge in said
second comminution surface (114) at a pressure point for preventing the
accumulation of uncomminuted specimen.
24. The sample retainer of claim 20 further including a
sample collector (72) engageable upon said funnel (96) in a friction fit, said
collector being insertable with said funnel into the machine as a unit.
25. The sample retainer of claim 19 wherein said funnel
(96) is self-supporting on a substrate.
26. The sample retainer of claim 19 wherein said funnel
(96) has a support grid (92) at a first end, and is configured for engaging a
collector in a friction fit at a second end (110, 104). 27. The sample retainer of claim 19 wherein said funnel has
a radially extending flange (138) provided with spaced lugs (140) for driving
engagement with the drive collars (38).
28. A method for operating a machine for comminuting a
plurality of biological specimens including a drive source, a plurality of drive
collars configured for being driven by the drive source, each said drive collar
configured for receiving a corresponding sample retainer, and a plurality of ram
keys each corresponding to a drive collar and configured for exerting a biasing
force on a ram element for causing comminution of a sample in the sample
retainer, said method comprising:
rotating the drive collars in a first direction for a first interval,
then rotating said drive collars in a second direction for a second interval.
29. The method of claim 28 wherein at least one of said first
and second intervals are at least one of a range of from about .5 to 10 seconds
in time and from .1 to 10 revolutions of said drive collars.
30. The method of claim 28 wherein said first interval is
distinct from said second interval. |
SYSTEM FOR COMMINUTION OF MULTIPLE SAMPLES OF BIOLOGICAL SPECIMENS
TECHNICAL FIELD
The present invention is generally related to methods and
apparatus for comminuting biological specimens onsite or in a laboratory,
and is more particularly related to devices used for providing biological
specimens for subsequent chemical analysis.
BACKGROUND ART
For the purposes of this application, the term "comminution"
will be understood to mean to mechanically reduce to powder, pulverize,
grind, shred, tear or otherwise increase the surface area of biological
specimens including, but not limited to hair, feathers, nails, hooves, claws,
horns, fur, beaks, scales and other sources of keratin, (or access to the cortex
of the specimen), as well as bone, tissue, organs and/or muscle found in
humans and animals (hereinafter referred to as biological specimens or
samples), whether or not in the presence of a carrier liquid, so that the
specimen is readily subject to extraction or detection of drugs and their
metabolites, compounds, chemicals or other pharmacologic agents. Testing
may also be undertaken to monitor patients' overall health, vitamin
deficiencies, effects of exposure to certain chemicals, and other purposes.
Increased drug abuse in North America has been associated
with criminal activities, health problems, newborn addiction, lost worker
productivity and staggeringly high medical costs. Currently of greatest
concern are opiates (heroin, morphine, codeine), cocaine, marijuana,
MDMA (Ecstasy), phencyclidine, amphetamine and methamphetamine.
Possible pesticide residues in the breast tissues of women and
the concern over the presence of synthetic agents and compounds in plant
and animal foodstuffs has raised concerns about possible environmental
exposure including air- and water-borne agents, as well as, exposure of
domestic animals to agricultural chemical agents such as pesticides and
herbicides, growth hormones and/or antibiotics. Verifying a natural
"organic" status prior to slaughter has, thus, recently become of significant
interest.
In testing for human drugs of abuse, several test systems are
presently marketed for detecting drug analytes in urine e.g., ONTRAK™
and ONLINE™ (Roche Diagnostic Systems, Inc.), the ADx™ automated
fluorescence polarization immunoassay system (Abbott Laboratories, Inc.)
and EZ-SCREEN™ (Environmental Diagnostics). Unfortunately, there are
significant problems associated with urine testing for drugs of abuse, e.g., (i)
possible false positive results for opiates recorded in subjects who are on
certain medications and who have recently ingested poppy seeds; (ii) rapid
elimination rates and short half-life of many drug metabolite compounds;
and particularly (iii) false negatives associated with purposeful adulteration,
dilution, urine substitution and other creative ways donors discover to beat a
drug test.
Unlike liquid urine samples, solid samples such as hair require
special sample preparation prior to conducting assays. Conceptually, hair
provides a better toxicological specimen than urine, serum, sweat or saliva
because its relatively slow growth increases the period of time during which
drug usage is detectable. Human head hair grows approximately 1/64
(0.016) inch per day, thus creating a calendar of drug use. It takes about
seven (7) days after ingestion of drugs for the drugs to be extractable from
hair outside the scalp. Approximately 1.5 inches of human head hair can
show drug usage over a ninety (90) day period. The hair can also be
sectioned into periods of thirty (30) day use.
In present day practice, extraction of drugs from hair often
involves cutting the hair into small pieces using razor blades or scissors and
inserting the cut hair into a test tube where it is then exposed to acid and/or
base hydrolysis, prolonged enzymatic digestion, heat, organic solvent
extraction and/or sonication. The cutting procedure is labor intensive, time
consuming and is subject to the particular cutting techniques of individual
technicians. Also, when multiple specimens need to be analyzed,
technicians are subject to repetitive stress injuries. These methods require
technical experience and are presently most easily conducted in a test
laboratory. However, even then the sample process can take two to three
hours to complete, and the results are not available for as long as seven days,
the samples frequently suffer from poor reproducibility, there are long
delays before results can be released and, even then, variability occurs in the
ability to isolate different drugs and their metabolites. Hydrolysis conditions
can also result in conversion of drug metabolites such as 6-
monoacetylmorphine, whose presence provides judicial proof of drug abuse,
into parent compounds, i.e., morphine. Fortunately, it has been found that
certain drugs and their metabolites can persist in hair for extended periods of
time.
Another method for preparing a sample of hair for chemical
analysis is for a technician to freeze dry the sample using liquid Nitrogen,
then grind the frozen hair in a mortar and pestle for 5 to 10 minutes until it is
powdery in appearance. This comminution or maceration operation is useful
for increasing the surface area of the hair and, thus reducing the reaction
time of the analytical chemicals on the sample and increasing extractability
of the agents of interest. Using this method the amount of prepared specimen
obtained for analysis may vary by sample as well as by individual
technician, and the liquid Nitrogen limits usage to a laboratory setting. An
alternative procedure for comminution involves a ball mill, but that device
inherently has contamination issues with the balls from sample to sample,
and is thus only useful in a laboratory process and this method of
comminution is relatively slow.
There is a need for a rapid mechanical comminution method
and apparatus for biological specimens which is easily adapted to both
portable on-site comminution and laboratory comminution to prepare
samples for detection of the agents of interest. There is also a need for a
comminution method and apparatus for such specimens which is repeatable
on an objective basis, maximizes sample integrity by eliminating cross
contamination between specimens, increases the surface area of the hair and
exposes the cortex of the hair for increased and rapid extractability of the
agents of interest.
DISCLOSURE OF THE INVENTION
The above-identified needs are met or exceeded by the present
apparatus for the comminution of biological specimens, which provides a
receiving unit and a preferably disposable sample retainer that can be
inserted into the receiving unit in one piece. As such, the specimen to be
comminuted, and the comminuted product, are installed and removed from
the receiving unit as one piece to increase processing efficiency and to
reduce the potential for cross-contamination of specimens. In the preferred
embodiment, the sample retainer includes comminution elements which
reduce the specimens to a granular or powder-like state for more efficient
and rapid detection for the agents of interest. The preferred receiving unit is
provided with a drive system for powering the comminution of at least one
and preferably multiple specimens. Further, the receiving unit is preferably
configured for enhancing the collection of ground specimen from the sample
retainer.
More specifically, an apparatus for comminuting biological
specimens includes a receiving component provided with a drive source, at
least one sample retainer configured for accommodating at least one
biological specimen and constructed and arranged for engagement in the
receiving component. The sample retainer includes a first component
configured for receiving a specimen prior to comminution and a second
component for receiving the specimen after comminution. In addition, the
sample retainer is insertable into the receiving component as a single piece.
In another embodiment, a machine for comminuting multiple
biological specimens is provided, each specimen being provided in a sample
retainer including a first component configured for receiving a specimen
prior to comminution, a second component for receiving the specimen after
comminution, and a ram element. The machine includes a drive source, a
plurality of drive collars configured for being driven by the drive source,
each drive collar configured for receiving a corresponding sample retainer,
and a plurality of ram keys each corresponding to one of the drive collars
and configured for exerting a biasing force on a corresponding ram element
for causing comminution of a sample in the sample retainer.
In yet another embodiment, a sample retainer for use with a
machine for comminuting biological specimens is provided, the machine
including a drive source, a plurality of drive collars and a like plurality of
ram keys. The sample retainer includes a cup, a funnel joinable to the cup,
at least one comminution surface associated with at least one of the cup and
the funnel, and upon joining, the cup and the funnel being insertable into the
machine as a unit.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a top perspective view of the present comminution
apparatus with portions omitted for clarity;
FIG. 2A is an upper half of an exploded perspective view of
the apparatus of FIG. 1;
FIG. 2B is a lower half of an exploded perspective view of the
apparatus of FIG. 1;
FIG. 3A is an upper half of an exploded perspective view of a
sample retainer, ram and sample collector suitable for use with the present
apparatus;
FIG. 3B is a lower half of the exploded perspective view of
FIG. 3 A, also depicting a portion of the receiving device;
FIG. 4A is an upper half of an exploded elevation of the
sample retainer and ram depicted in FIGs 3A and 3B;
FIG. 4B is the lower half of an exploded elevation of the
sample collector and receiving device of FIG. 3B;
FIG. 5 is a bottom perspective view of the present funnel
portion of the sample retainer;
FIG. 6 is a top perspective view of the receiving device
depicted in FIGs. 3B and 4B;
FIG. 7 is an enlarged fragmentary plan view of a type of
comminution surface suitable for use with the present sample retainer;
FIG. 8 is a section taken along the line 8-8 of FIG. 7 and in the
direction generally indicated;
FIG. 9 is an enlarged fragmentary plan view of a second type
of comminution surface suitable for use with the present sample retainer;
FIG. 10 is a section taken along the line 10-10 of FIG. 9 and in
the direction generally indicated;
FIG. 11 is a fragmentary bottom perspective view of the
apparatus of FIG. 1 showing detail of the ram keys and engagement with the
ram; and
FIG. 12 is a fragmentary top perspective view of the
assembled ram key, sample retainer and drive assembly of the present
apparatus.
BEST MODE FOR CARRYING OUT THE INVENTION
Referring now to FIGs. 1, 2A, 2B and 4B, an apparatus or
device for comminuting biological specimens or samples is generally
designated 10 and is intended for comminuting specimens or samples such
as hair, nails, fur, feathers, hooves or other materials having keratin, as well
as other biological products such as muscle, organ and/or bone or which are
known or believed to contain compounds accessible through chemical
analysis and other detection systems. While the present apparatus 10 is
depicted in a configuration for processing multiple specimens at a time, it is
contemplated that, depending on the application, a single specimen may be
comminuted in the apparatus. In the preferred embodiment, the apparatus
10 is configured for placement upon a table or other work surface, and the
use of terms such as "top", "bottom", "upper" and "lower" refer to the
apparatus 10 oriented as depicted in FIG. 1, however other orientations are
contemplated depending on the application.
More specifically, the apparatus 10 preferably includes a
housing or cabinet 12 having a lid 14, two sidewalls 16, two endwalls 18 and
a bottom 20. While the cabinet 12 is shown as box-like, other shapes are
contemplated depending on the application. As is known in the art, one or
more of the side or endwalls 16, 18 may be readily removable for access to
the interior for adjustments, repairs and the like. Also included on the
cabinet 12 are a base plate 22 and a drive support tray 24.
Preferably configured for receiving and processing sample
retainers, generally designated 26, provided in a unitary or one-piece format,
the apparatus 10 is also designed for processing or comminuting multiple
sample retainers simultaneously. A sample retainer-receiving component,
generally designated 28 is supported within the cabinet 12 upon the drive
support tray 24 below the base plate 22, and is operationally connected to a
drive source 30, made up in part of a motor 32 (FIG. 2B) preferably an
electric motor having a drive shaft 33 and located within the cabinet 12
below the support tray 24. However, the type of motor 32 and its location
may vary to suit the application. In the preferred embodiment, the drive
source 30 includes a drive pulley 34 operationally connected to the drive
shaft 33 as is known in the art and, upon assembly located above the support
tray 24.
Referring now to FIGs. 2A and 12, a serpentine drive belt 36 is
engaged on the drive pulley 34 and around a plurality of drive collars 38.
While the present pulley and belt drive source 30 is preferred, it is
contemplated that a gear drive, chain and sprocket arrangement, individual
motors for each collar, or even a pneumatic powered turbine system would
be suitable for driving the drive collars 38. In the preferred embodiment
there are four drive collars 38, however the number and arrangement of the
drive collars may vary to suit the application. The drive collars 38 are
preferably linearly aligned on the support tray 24 and rotatably engage collar
bearing saucers or retainer rings 40 mounted to corresponding collar bores
42 in the support tray. Each retainer ring 40 encloses a ball bearing 43 for
facilitating rotation of the collar 38 relative to the retainer ring and for the
mounting of the bearing to the tray 24. To facilitate location of the collar 38
in the ball bearing 43, each collar 38 is preferably located with a key rib 41
(FIG. 4B) which keys into a corresponding receptacle on the ball bearing.
Also included in the drive source 30 is an idler pulley 44
rotatably secured to the support tray 24 and slidably adjustable as is known
in the art to adjust the tension of the drive belt 36. The drive belt 36 is
threaded around the idler pulley 44, which is preferably located midway
between the four drive collars 38, however its location may vary to suit the
application provided the function of belt tensioning is achieved. A pulley
tensioner 45 is provided for allowing user adjustment to the tension on the
drive belt 36.
Referring now to FIG. 6, each drive collar 38 is provided with
a drive belt groove 46 around an outer periphery, constructed and arranged
for receiving the drive belt 36, and an axially projecting support ring 48
which projects through a corresponding opening 49 in the base plate 22 and
also defines a central throughbore 50. The throughbore 50 is coaxial with
the collar bores 42 of FIG. 2A. A counterbore 52 in the throughbore 50
defines a shoulder upon which are located a plurality of spaced, radially
oriented teeth 54. Once assembled, the drive source 30 is protected by the
base plate 22, which is secured to the support tray 24 by conventional
removable fasteners. Upon assembly of the drive source 30, and activation
of the motor 32, rotation of the drive pulley 34 will cause simultaneous
rotation of the drive collars 38 through action of the drive belt 36.
Returning now to FIGs. 1, 2 A and 2B, the lid 14 is supported
upon the base plate 22 by a hinge 56 and a conventional dampening cylinder
58 mounted to the underside of the lid and to the base plate in a conventional
manner. The cylinder 58 prevents the lid 14 from falling upon the
technician's hands or arms during installation and retrieval of the sample
retainers 26. Also provided on the lid 14 is at least one handle 60
constructed and arranged to facilitate closure by a technician.
A ram key rack 62 is mounted to the underside of the lid 14
and defines a downward-opening, generally "U"-shaped channel. Into the
channel are mounted a plurality of ram keys 64 (best seen in FIG. 11), the
number of which corresponds to the number of drive collars 38. Preferably,
the ram keys 64 are each disposed in the rack 62 to be coaxial with the
corresponding central throughbore 50. The operation of the ram keys 64
will be described in greater detail below.
Also provided on the cabinet 12 is a latch 66 for securing the
lid 14 to the base plate 22 and the drive support tray 24. Below the drive
support tray 24, a plurality of sample collector receiving pockets 68 are
secured to the front sidewall 16 of the cabinet 12, preferably to the underside
of the tray, and each pocket is constructed and arranged for receiving and
supporting a corresponding sample collector, generally designated 72, which
is part of each sample retainer 26. Lifting handles 74 (FIG. 2B) are provided
as desired on the cabinet 12 to facilitate portability of the apparatus 10.
Referring now to FIGs. 3A, 3B, 4A and 4B, the sample
retainer 26 will be described in greater detail. The sample retainer 26
includes a first component or cup 80 configured for receiving a specimen
prior to comminution. In the preferred embodiment, the cup 80 is a
generally cylindrical sleeve defining an axially extending throughbore 82. A
lower end 84 is configured as a skirt extending radially from the wall of the
cup 80.
The throughbore 82 is closed off by a comminution material
disk 86 forming a first comminution surface. In the preferred embodiment,
the disk 86 is generally planar and made of perforated metal made from, or
using techniques known in the electric shaver art for producing electric
shaver foil having apertures in the approximate range of 0.025 inch,
however the size and shape of the openings in the disk may vary to suit the
application, provided they are large enough to pass comminuted hair fibers
therethrough. Human hair fibers typically have a diameter in the range of
0.002-0.004 inch. While a shaver foil or similar perforated disk is the
preferred material and construction for the comminution surface 86, it is
contemplated that other materials would be suitable provided they produce
comminuted hair, feathers, nails, hooves, horns, fur, beaks, and other
sources of keratin or other specimens found in humans and animals suitable
for chemical analysis and other detection systems.
Referring now to FIGs. 9 and 10, an exemplary pattern of
comminution bosses 88 is depicted. The bosses 88 are produced by
electroforming, photoetching, stamping or similar techniques known in the
shaver foil art to project axially from a plane 89 defined by the surface 86,
and are formed in a generally square or polygonal shape, however it is
contemplated that the shape may vary to suit the application. Through the
manufacturing process, the bosses 88 have sharp outer edges 90 which
perform the comminution. While other spacing is contemplated, depending
on the situation and the subject matter to be comminuted, it has been found
that a spacing of approximately .028 inch between center points of adjacent
bosses 88 (distance "D" in FIG. 9) has provided positive results. Also, the
bosses 88 preferably have a height equal to or less than the diameter of
human hair fibers. However, the height of the bosses 88 may vary to suit the
application, and all bosses may not necessarily have the same height.
Referring again to FIGs. 3A, 3B, 4A, 4B and 5, since the disk
86 is made of relatively thin material, it is preferred that it be supported in
the sample retainer 26. This support is provided by a support grid 92 made
up of first and second pluralities of spaced bars 93 oriented preferably
normally to each other or radially or in other orientations so that a
supportive yet porous surface is obtained. The grid 92 is secured within an
upper counterbore 94 of a second component of the sample retainer 26,
generally designated a funnel 96. The skirt 84 is secured to an exterior of a
lip 98 of the funnel 96, located at an upper end 100 of the funnel.
Preferably, the attachment of the grid is accomplished by ultrasonic welding
the skirt 84 to the lip 98, which captures the disk 86 and the grid 92 in place.
However, chemical adhesives or other suitable fastening technologies are
contemplated. It is also contemplated that the comminution surface 86 may
be integrally formed with the grid 92 and even be made of the same
material.
Upon fastening the cup 80 to the funnel 96, the sample retainer
26 is formed into a single piece, which is the preferred form in which it is
inserted into the receiving component 28. Additional preferred components
of the sample retainer 26 include the sample collector 72, which in the
preferred embodiment is a test tube. Among others, suitable test tube sizes
include 12X75mm, 10X40mm, 13X45mm, 13X50mm and 13X60mm.
Alternatively, the known "Hitachi" cups are contemplated sample collectors
72, as well as other laboratory standard test tubes and other holding vessels
known to those skilled in the art. However, it is contemplated that other
types of containers would be suitable in this application as sample collectors
72.
The funnel 96 is configured for receiving the biological sample
after comminution, and as such is tapered toward a lower end 102. To
frictionally engage the sample collector 72, the lower end 102 is formed
with a generally cylindrical nozzle 104 which tightly engages an inner
diameter of the collector 72. Thus, the funnel 96 is contemplated as being
designed to correspond with a suitable type of collector. At least three and
preferably four fin-like legs 106 are used for enabling the funnel to be self
supporting on a substrate such as a laboratory table. At least two of the legs
106 are provided on an inner edge 108 with an arcuate tab formation 110
which complements the nozzle 104 by engaging an outer periphery of the
collector 72. The collector 72 is thus sandwiched at its upper end between
the nozzle 104 and the tab formations 110 for a snug, friction fit. In the
preferred embodiment, the collector 72 is supported on the sample retainer
26 only by its engagement with the funnel 96 as described above.
Referring now to FIGs. 3 A and 4A, in the preferred
embodiment, a ram element or ram 112 is part of the sample retainer. The
ram 112 is configured to provide a second comminution surface 114
constructed and arranged to move relative to the comminution surface 86 on
the cup 80 for comminuting specimens placed therebetween. While other
arrangements are contemplated, the first comminution surface 86 moves
relative to the second comminution surface 114, and preferably, that
movement takes the form of rotation. The cup 80, the funnel 96, the sample
collector 72 and the ram 112 are preferably assembled and placed as a unit
or a single piece into the drive collar 38 and, with the exception of the ram,
rotated therewith.
While admittedly the ram 112 and the sample collector 72 are
not permanently fixed to the cup 80 and the funnel 96, for the purposes of
this application, they are referred to as being installed into the apparatus 10
as one piece, since they are installed as a unit to be engaged in the drive
collar 38. This preferred unitary assembly and handling has been found to
reduce cross contamination between samples. As will be described below in
greater detail, the ram 112 is held stationary relative to this rotary movement
while the sample retainer 26 is engaged in the apparatus 10.
More specifically, the ram 112 has a generally cylindrical
body 116 dimensioned to slidably telescope into the axial throughbore 82 of
the cup 80 and rotate relative to the throughbore while telescopingly
engaged. The second comminution surface 114 is secured to a closed end
118, as by chemical adhesive, sonic welding or similar fastening technology.
Alternatively, it is contemplated that the surface 114 may be applied to the
closed end 118 by electroplating or electrodeposition, or may be integrally
formed on the closed end. An optional depending formation or boss 119 is
formed to depend from the closed end 118 to create a slight axial bulge or
protrusion in the comminution surface 114. The formation 119 is generally
elliptical when viewed in plan and is configured for causing the bulge in the
surface 114 to engage the comminution surface 86 at the highest pressure
point during operation for preventing accumulation of uncomminuted hair,
especially the creation of hair balls in the middle of the comminution
surface. The relatively small height of approximately .012 inch of the
formation 119 does not interfere with the other action of the surfaces 114, 86
relative to each other. It is contemplated that the height and/or shape of the
formation 119 may vary to suit the application.
At an opposite, open end 120, a peripheral edge 122 is
provided with a plurality of ram teeth 124 projecting along an axis generally
parallel to an axis of rotation of the sample retainer 26. The peripheral edge
122 also preferably includes a radially projecting lip 126. In some
applications, engagement of the lip 126 upon a corresponding upper end 128
of the cup 80 regulates the relative position of the comminution surfaces 86,
114. It is preferred that some spacing be defined between the surfaces 86,
114 for facilitating comminution of the hair sample. Since the diameter of a
typical strand of hair is in the range of 0.002-0.004 inch, favorable
comminution results have been obtained when the spacing between the
surfaces 86, 114 is in a similar range.
Referring now to FIGs. 7 and 8, the preferred comminution
surface 114 is viewed in greater detail. While other configurations are
contemplated depending on the type of biological material to be
comminuted, when hair is the desired biological material, the comminution
surface is preferably provided with a plurality of spaced, generally circular
bosses 130 which are formed by die forming and lapping, or alternatively by
electroforming or photoetching onto a generally planar surface 132.
Relatively sharp peripheral edges 134 formed in the stamping process
perform comminution when moved relative to the surface 86. While other
spacings are contemplated, it is preferred that the center-to-center distance
"T" between adjacent bosses 130 is approximately .064 inch. It is
contemplated that the boss height may vary to suit the application or the
sample type and size, and that boss height may vary within or upon the same
surface 86, 114.
While shaver foil is the preferred material for the surfaces 86,
114, and while the comminution apparatus is presently disclosed in the form
of the opposed comminution surfaces, other comminution surfaces or
apparatus capable of comminuting hair, feathers, nails, hooves, horns, fur,
beaks, and other sources of keratin or other types of specimens found in
humans and animals are contemplated. For example, it is contemplated that
the surfaces 86, 114 may be made of other materials, including metals such
as stainless steel, nickel, aluminum alloys of the above and similar metals,
plastics, abrasives such as sandpaper, silica carbide or other suitable abrasive
or grinding materials. It is further contemplated that the foil surfaces 86,
114 may be exchanged on the respective cup 80 and the ram 112 and also
that the ram may rotate relative to the cup.
Referring now to FIGs. 5 and 6, the sample retainer 26 is
rotated relative to the ram 112 by engagement of the funnel 96 in a
corresponding one of the drive collars 38. Opposite the nozzle 104, the
funnel 96 is provided at the upper or opposite end 100 with a radially
projecting flange 138 having a plurality of spaced, depending, radial
extending lugs 140. While the size and spacing of the lugs may vary to suit
the application, in the preferred embodiment, each standard or relatively
larger size lug 140 alternates with a relatively smaller lug 142. The spacing
and configuration of the lugs, 140, 142 is designed to drivingly mesh with
the complementary spaced, radially extending teeth 54 of the drive collar
(FIG. 6). Upon insertion of the sample retainer 26 into the apparatus 10, the
support ring 48 facilitates the location of the funnel 96 into the central
throughbore 50 so that the lugs 140, 142 will drivingly engage the teeth 54.
Also, the radially projecting flange 138 is matingly received in the
throughbore 50 and is circumscribed by the support ring 48.
Referring now to FIGs. 11 and 12, the ram key rack 62 and a
pair of the ram keys 64 are shown in greater detail. Each ram key 64 has a
generally conical shape, with a tapered end 150 configured for location in
the open upper end 120 of the ram 112. A radially flared upper end 152 is
joined to a base 154 which abuts an underside 156 of the ram key rack 62.
The base 154 is polygonal and preferably is square or rectangular and is of
sufficient size so that it is constrained against rotation by the ram key rack
62. A threaded fastener 158 secures the ram key 64 to the rack 62, and a
biasing element 160 such as a coiled spring or the like biases the key 64
towards the corresponding drive collar 38. At least one and preferably two
diametrically opposed key formations 162 are constructed and arranged to
locate between the spaced ram teeth 124.
Once the sample retainer 26 is loaded with a specimen
between the two comminution surfaces 86, 114 and is placed in the open
drive collar 38, the lid 14 is closed and the biased ram key 64 engages the
corresponding ram 112. The ram 112 is thus prevented from rotating
relative to the cup 80, the funnel 96 and the sample collector 72 once those
components are rotated as the drive collar 38 is rotated by the motor 32.
Another function of the biasing element 160 is to urge the ram 112, and the
corresponding second comminution surface 114 against the comminution
surface 86 and the sample retained therebetween to achieve the desired
comminution.
Referring now to FIGs. 2A and 12, it has been found that
collection of comminuted biological sample material is enhanced in some
applications by vibrating the sample retainer 26 in conjunction with the
comminution operation. The vibrations may be induced during or after the
comminution action, here preferably obtained through relative rotation of the
cup 80 and the ram 112. In the preferred embodiment, the vibration is
generated by a solenoid 164 disposed in operational relationship to a linkage
bar or arm 166 having a plurality of attached open rings 168. The arm 166
is secured to an underside of the tray 24. As seen in FIG. 12, the rings 168
are each dimensioned to loosely circumscribe a corresponding one of the
funnels 96. Vibrations in the form of repetitive "taps" generated by the
solenoid 164 are transmitted through the arm 166, the rings 168 and
ultimately to the funnels 96. Comminuted specimen particles are thus
encouraged to move down through the nozzle 104 of the funnel 96 and into
the sample collector 72. The above apparatus is a preferred system for
applying vibrations to the sample retainer 26, however it is contemplated
that other vibration generators may be employed, such as eccentric tappers,
electromagnetic motors, sonic vibrators or similar mechanisms or devices
which generate vibrations or shock waves to facilitate the movement of
specimens down the funnel 96.
It has been found that the motor 32 is controllable to obtain
various types or degrees of comminution. For example, the motor 32, and
the corresponding drive collars 38 may be rotated for a specified period of
time, and then the sample retainers removed. Alternately, the drive collars
38 may be rotated first in a first direction for a specified period of time, then
the direction of rotation can be reversed for another period of time, which
can be the same or different from the period of rotation in the first direction.
In one embodiment, the direction of rotation and timing is approximately 0.5
second in a first direction, then 0.5 second in a reverse direction. Timing
ranges of between about 0.5 to 10 seconds are contemplated. Rotational
direction and timing of comminution are contemplated as being variable to
suit the application. The preferred range of revolution for the collars 38 is
from about 0.1 to 10 revolution(s) in each direction, with 2 to 3 revolutions
being especially preferred. It is also contemplated that the timing and/or
amount of rotation may vary in each direction. Appropriate motor
controllers (not shown) as are well known in the art are contemplated as
being employable for operation of the motor 32 in this manner.
Referring again to FIG. 12, an optional feature of the apparatus
10 is the capability of varying, either constantly or intermittently, the
pressure exerted by the corresponding comminution surface 114 of the ram
112 against the surface 86 of the cup 80. This pressurization has been
found in some cases to reduce the formation of uncomminuted "hair balls"
in the cup 80. More specifically, at least one fluid power cylinder 170, and
preferably a pneumatic cylinder for each drive key 64, is provided on an
upper surface 172 the drive key rack 62. A piston or control rod 174 is
activated by a compressor and control valve as is known in the art (not
shown) to extend a desired distance "D" and thus exert pressure against an
underside of the housing lid 14. Since, during operation of the apparatus 10,
the lid is secured by the latch 66, the pressure exerted by the cylinder 170
causes a downward force against the driver key 64, and ultimately, the ram
112. By controlling the pressurization of the cylinders 170, variation in the
amount and timing of pressure may be exerted against the rams 112. The
pressure may be intermittent, constant or not exerted at all, depending on the
conditions of the particular sample.
Upon completion of the comminution process, the duration of
which may vary to suit the situation, the user lifts the lid 14 and removes the
sample retainer 26 as a unit or in one piece from the drive collar 38. The
opening of the lid 14 disengages the ram keys 64 from the rams 112. With
care being taken to avoid contamination of the comminuted sample, the
technician or user removes the sample collector 72 from the nozzle 104 of
the funnel 96 and processes the sample further to determine whether target
substances are present as is known in the art. While it is preferred that the
sample retainer 26 is disposable to avoid cross-contamination of specimens,
it is also contemplated that the sample retainer may be subject to a washing
and/or sterilization procedure for reuse.
While specific embodiments of the present system for
comminution of multiple samples of biological specimens has been shown
and described, it will be appreciated by those skilled in the art that changes
and modifications may be made thereto without departing from the invention
in its broader aspects and as set forth in the following claims.
Next Patent: QUICK CHANGE MOUNTING SYSTEM FOR A FAUCET