U.S. patent application number 13/229075 was filed with the patent office on 2012-03-15 for input/output module and overall temperature control of samples.
This patent application is currently assigned to HAMILTON STORAGE TECHNOLOGIES, INC.. Invention is credited to Scott Collins, Frank Hunt, Julian Warhurst, Bruce Zandi.
Application Number | 20120060520 13/229075 |
Document ID | / |
Family ID | 44681425 |
Filed Date | 2012-03-15 |
United States Patent
Application |
20120060520 |
Kind Code |
A1 |
Collins; Scott ; et
al. |
March 15, 2012 |
Input/Output Module and Overall Temperature Control of Samples
Abstract
An automated storage and retrieval system for storing chemical
and biological samples includes freezer chests maintained at an
ultra-low temperature (e.g. -80.degree. C.) or a cryogenic
temperature. The freezer chests are located within a refrigerated
(e.g. -20.degree. C.) enclosure. Samples are loaded through a wall
of the enclosure and are then transferred to an input/output buffer
section in an ultra-low temperature or cryogenic freezer chest that
is thermally segregated from a long-term storage section in the
same freezer. Specialized input/output cassettes are used for
transferring the samples through an input/output module into the
system.
Inventors: |
Collins; Scott; (Westford,
MA) ; Hunt; Frank; (Shrewsbury, MA) ;
Warhurst; Julian; (Ashland, MA) ; Zandi; Bruce;
(Lexington, MA) |
Assignee: |
HAMILTON STORAGE TECHNOLOGIES,
INC.
Hopkinton
MA
|
Family ID: |
44681425 |
Appl. No.: |
13/229075 |
Filed: |
September 9, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61381832 |
Sep 10, 2010 |
|
|
|
Current U.S.
Class: |
62/62 ; 62/378;
62/381 |
Current CPC
Class: |
F17C 3/085 20130101;
B01L 2300/04 20130101; G01N 2035/0425 20130101; G01N 35/0099
20130101; B01L 9/06 20130101; G01N 2035/042 20130101; A01N 1/0252
20130101; B01L 2300/021 20130101; B01L 2200/026 20130101; F25D
25/00 20130101; F25D 25/04 20130101; B65G 1/00 20130101; A01N
1/0236 20130101; G01N 1/42 20130101; B01L 7/50 20130101; G01N 35/04
20130101; G01N 2035/0462 20130101; B01L 2200/04 20130101; G01N
2035/00435 20130101; G01N 2035/00346 20130101 |
Class at
Publication: |
62/62 ; 62/378;
62/381 |
International
Class: |
F25D 25/00 20060101
F25D025/00 |
Claims
1. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature, the
system comprising: a refrigerated enclosure maintained at a
temperature of approximately -15.degree. C. to -30.degree. C.; at
least one sample input/output module for passing samples through a
wall of the enclosure; and one or more freezer chests located
within the refrigerated enclosure and having a freezer bay for
storing the samples that is maintained at a set temperature at or
below -65.degree. C. under normal operating conditions, wherein an
input/output buffer section comprising a freezer bay or a portion
of a freezer bay in one of the freezer chests is thermally
segregated from long term sample storage sections in the same or
other of said freezer chests; and further wherein samples placed
into the system through the sample input/output module are
transferred to the input/output buffer section in order to cool the
samples to a temperature at or near the set temperature of the one
or more freezer chests prior to transferring the samples to a long
term storage location in one of the freezer chests removed from the
input/output buffer section.
2. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 1 wherein the input/output module comprises:
multiple input/output cassettes for transferring samples stored in
tube storage racks or plates into the refrigerated enclosure from
outside of the system and from inside the refrigerated enclosure to
outside the system; a carousel; multiple bays on the carousel for
holding one of said input/output cassette; a loading/unloading
station including an opening through the enclosure wall, at least
one door covering the opening and manually accessible from outside
of the enclosure when the door is opened; wherein sample tube
storage racks or plates can be manually placed on or removed from
shelves on an input/output cassette located at the input/output
station when the at least one doors are open.
3. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 2 wherein the input/output module further
comprises an air purging system to purge the space between the at
least one or more doors of the input station and the carousel.
4. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 2 further comprising: an array of storage
cassettes removably located in one of the freezer chests for long
term storage of samples stored in tube storage racks or plates; and
a cassette puller located in the refrigerated enclosure that places
input/out cassettes in and retrieves input/output cassettes from
the bays on the carousel of the input/output module, and further
transfers input/output cassettes and storage cassettes within the
refrigerated enclosure to the one or more freezer chests, the
cassette puller comprising in part a sleeve into which the
respective cassette is lifted at least partially, the sleeve
containing at least one access opening to allow removal of a
selected tube storage rack or a plate on a shelf in the lifted
cassette or allow placement of a tube storage rack or a plate on an
empty shelf in the lifted cassette.
5. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 2 wherein the input/output module further
comprises an insulated housing surrounding the carousel and bays
for holding input/output cassettes.
6. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 2 wherein each bay in the carousel of the
input/output module comprises a vertical sleeve for holding
input/output cassettes in the respective bay, and the sleeve
includes three thermally insulated walls.
7. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 6 wherein a front side of the sleeve includes a
top shield covering a top portion of the sleeve and bottom shield
covering a lower portion of the sleeve and an area between the
shields that provides access to load and unload samples from an
input/output cassette located in the sleeve when the input/out
cassette is located at the loading/unloading position on the
carousel.
8. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 1 further comprising multiple input/output
cassettes each for holding sample tubes, storage racks or plates
and each input/output cassette comprising: a sample storage portion
having a plurality of generally vertical, spaced shelves each for
holding a sample tube storage rack or plate; a top plate located
above the sample storage portion with an upper portion that is not
intended to hold sample tube storage racks or plates spanning
between the sample storage portion and the top plate; and a bottom
plate located below the sample storage portion with a lower portion
that is not intended to hold sample tube storage racks or plates
located between the sample storage portion and the bottom
plate.
9. In an automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 2, a method of loading samples through the
input/output module into the system when the samples loaded into
the system are warm compared to freezer set temperature, the method
comprising the following steps: a) placing an empty input/output
cassette in one of the bays on the carousel of the input/output
module when the bay is located at a designated cassette transfer
location; b) rotating the carousel to present the input/output
cassette to the loading/unloading station; c) opening the one or
more doors to provide manual access by a user to the shelves in the
input/output cassette presented at the loading/unloading station;
d) manually loading tube storage racks or plates into shelves on
the input/output cassette located at the loading/unloading station;
e) closing the one or more doors; f) repeating steps a) through e)
as necessary to accommodate all of the samples that need to be
loaded into the system; g) when the carousel rotates so that a
loaded input/output cassette is located at the designated cassette
transfer location, transferring the loaded input/output cassette to
the input/output buffer section in the at least one freezer
bay.
10. The method recited in claim 9 further comprising the following
step: cooling empty input/output cassettes in the input/output
buffer section prior to placing the empty input/output cassette in
the bay on the carousel.
11. The method recited in claim 9 further comprising the following
step: providing a dry air purge when the one or more doors are
opened to provide manual access by a user to the shelves in an
input/output cassette presented at the loading/unloading
station.
12. The method recited in claim 9 wherein the input/output cassette
includes a removable module with multiple shelves, and the multiple
shelves are configured to be preloaded with tube storage racks or
plates prior to loading the samples into the input/output cassette
when it is located at the loading/unloading station.
13. In an automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 2, a method of loading samples through the
input/output module into the system when the samples being loaded
into the system have a temperature at or near the freezer set
temperature, the method comprising the following steps: a) placing
an empty input/output cassette in one of the bays on the carousel
of the input/output module when the bay is located at a designated
cassette transfer location, wherein the empty input/output cassette
is cooled in the input/output buffer section prior to placing the
empty input/output cassette in the bay on the carousel; b) rotating
the carousel 180.degree. to position the pre-cooled, empty
input/output cassette to the loading/unloading station; c) opening
the one or more doors at the loading/unloading station to provide
manual access by a user to shelves in the input/output cassette
presented at the loading/unloading station; d). loading the cold
tube storage racks or plates into the input/output cassette located
at the loading/unloading station, while at the same time placing a
next pre-cooled, empty input/output cassette from the input/output
buffer section into a bay located at the designated cassette
transfer location 180.degree. around the carousel from the
loading/unloading location; e) closing the one or more doors; f)
rotating the carousel 180.degree. to contemporaneously position the
next pre-cooled, empty input/output cassette at the
loading/unloading station and to position the loaded input/output
cassette at a designated cassette transfer location; g) repeating
steps a) through f) as necessary to accommodate all of the samples
that need to be loaded into the system; h) when the carousel
rotates so that a loaded input/output cassette is located at the
designated cassette transfer location, transferring the loaded
input/output cassette to the input/output buffer section in the at
least one freezer bay prior to placing the next pre-cooled, empty
input/output cassette into the bay on the carousel located at the
designated cassette transfer position.
14. The method recited in claim 13 further comprising the following
step: providing a dry air purge when the one or more doors are
opened to provide manual access by a user to the shelves in an
input/output cassette presented at the loading/unloading
station.
15. The method recited in claim 13 wherein the input/output
cassette includes a removable module with multiple shelves, and the
multiple shelves are configured to be preloaded with tube storage
racks or plates prior to loading the samples into the input/output
cassette when it is located at the loading/unloading station.
16. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 1 wherein the input/output cassette further
comprises tapered, rigid legs attached to the bottom of the
cassette.
17. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 8 wherein the top plate has an upwardly extending
retrieval catch.
18. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 17 wherein the top plate further includes guide
holes for accepting locator pins on a cassette puller.
19. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 8 wherein the compartments in the a sample storage
portion include sidewalls and the compartment shelves extend
further forward than the sidewalls.
20. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 2 wherein an outer surface of the respective
input/output cassettes includes position referencing stops for each
compartment within the input/output cassette.
21. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature as
recited in claim 8 wherein a sleeve is contained within each
carousel bay and includes a shield covering the location of the
upper portion and the lower portion when the input/output cassette
is located within the sleeve in the bay.
22. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature, the
system comprising: a refrigerated enclosure maintained at a low
temperature of approximately -15.degree. C. to -30.degree. C.; at
least one sample input/output module for passing samples through a
wall of the enclosure; one or more freezer chests located within
the refrigerated enclosure having a freezer bay maintained at a set
temperature at or below -65.degree. C. under normal operating
conditions for storing samples; multiple input/output cassettes for
holding sample tube storage racks or plates, each input/output
cassette comprising a sample storage portion having a plurality of
generally vertical, spaced shelves each for holding a sample tube
storage rack or plate, the shelves being oriented generally
vertical to one another, and a bottom plate located below the
sample storage portion and a lower portion that is not intended to
hold sample tube storage racks or plates spanning between the
sample storage portion and the bottom plate.
23. An input/output cassette as recited in claim 22 further
comprising a top plate located above the sample storage portion and
an upper portion that is not intended to hold sample tube storage
racks or plates spanning between the sample storage portion and the
top plate.
24. An input/output cassette as recited in claim 22 wherein the
input/output cassette further comprises tapered, rigid legs
attached to the bottom of the cassette.
25. An input/output cassette as recited in claim 22 wherein the top
plate has an upwardly extending retrieval catch.
26. An input/output cassette as recited in claim 22 wherein the top
plate further includes guide holes for accepting locator pins on a
cassette puller.
27. An input/output cassette as recited in claim 22 wherein the
compartments in the sample storage portion include sidewalls and
the compartment shelves extend further forward than the
sidewalls.
28. An input/output cassette as recited in claim 22 wherein an
outer surface of the input/output cassette includes position
referencing stops for each compartment within the sample storage
portion of the input/output cassette.
29. An automated storage and retrieval system for storing sample
tube racks or plates at an ultra-low or cryogenic temperature, the
system comprising: a refrigerated enclosure maintained at a
temperature of approximately -15.degree. C. to -30.degree. C.; one
or more freezer chests located within the refrigerated enclosure
and having a freezer bay for storing samples that is maintained at
a set temperature at or below -65.degree. C. under normal operating
conditions; said samples being stored in storage cassettes for long
term storage; multiple input/output cassettes for transferring
samples stored in tube storage racks or plates into the
refrigerated enclosure from outside of the system and from inside
of the refrigerated enclosure to outside of the system; and an
input/output module comprising a carousel, multiple bays in the
carousel for holding either input/output cassettes or storage
cassettes, and an loading/unloading station including an opening
through the enclosure wall, at least one door covering the opening
and manually accessible from outside of the enclosure when the door
is opened; wherein both input/output cassettes and storage
cassettes can be removed from or placed into the input/output
module at the loading/unloading station.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent
Application No. 61/381,832, filed on Sep. 10, 2010 entitled "Large
Automated Storage and Retrieval System for Storing Biological or
Chemical Samples at Ultra-Low or Cryogenic Temperatures".
FIELD OF THE INVENTION
[0002] The invention relates to automated storage and retrieval
systems for ultra-low temperature or cryogenic freezer systems used
primarily to store biological or chemical samples. In particular,
the present invention pertains to systems and methods for
efficiently inputting and retrieving samples from the freezers
without causing significant temperature rise of other samples
stored within the system.
BACKGROUND OF THE INVENTION
[0003] Storage of biological and chemical samples is becoming
widespread in the biotechnology and medical industries. To preserve
many of these samples, the samples must be stored well below normal
freezing temperatures. Generally speaking, a regular freezer
operates from about -5.degree. C. to -20.degree. C., an ultra-low
temperature freezer operates from about -50.degree. C. to about
-130.degree. C. (preferably at about -80.degree. C.), and a
cryogenic freezer operates from about -140.degree. C. to about
-196.degree. C. (the boiling point of liquid nitrogen). The present
invention is directed to a large automated storage and retrieval
system containing one or more ultra-low temperature or cryogenic
freezer chests operating below about -65.degree. C. The freezers
are contained within a refrigerated enclosure, preferably
maintained at about -20.degree. C. Most biological samples stored
in ultra-low temperature or cryogenic systems are contained in
sealed plastic laboratory tubes held in tube storage racks in
arrays of for example 48, 96 or 384 tubes. In some cases, the
biological samples are stored in sample storage plates such as
sealed microtiter or wellplates, rather than stored in sealed tubes
held in a rack.
[0004] The inventors have discovered that introducing warm samples
into the system, for example when samples arrive from a processing
laboratory, can cause temperature rise among other samples stored
in the system unless steps are taken to eliminate or mitigate the
temperature rise. The present invention is directed primarily to
maintaining the thermal integrity of samples during sample
introduction into the system.
SUMMARY OF THE INVENTION
[0005] As mentioned, the invention pertains to automated storage
and retrieval systems for storing sample tube storage racks or
plates at an ultra-low or cryogenic temperature. In particular, a
system implementing the invention has a refrigerated enclosure
maintained at a temperature of approximately -15.degree. C. to
-30.degree. C., and one or more freezer chests, normally a bank of
multiple freezer chests, located within the refrigerated enclosure.
The freezer chests contain compartments that are preferably
maintained, under normal operating conditions, at a designated
temperature setting at or below -65.degree. C., such as about
-80.degree. C. for an ultra-low temperature system. While samples
are stored in the freezer chests, a sample input/output module is
provided to pass samples through the wall of the refrigerated
enclosure so that samples can be robotically transferred within the
refrigerated enclosure to the freezers for storage. In accordance
with one aspect of the invention, at least one freezer bay or a
portion of one freezer bay is defined as an input/output buffer
section and is thermally segregated from long-term sample storage
sections in the same or other freezer bays. For example, the
input/output buffer section can comprise an insulated wall in a
single freezer bay thermally segregating the input/output buffer
section and the sample storage section. Alternatively, selected
nesting tubes in the freezer bay for storing cassettes holding
vertical arrays of sample tube storage racks or plates can be
separated and thermally isolated from other nesting tubes in the
freezer bay by placing insulation in a selected row or column of
nesting tubes otherwise intended to hold cassettes. Preferably,
samples placed into the system through the sample input/output
module are transferred to the input/output buffer section in order
to cool the samples to a temperature at or near the designated
temperature setting for the freezers (e.g. -80.degree. C.) prior to
transferring the samples to a long-term storage location in the
same or different freezer chest. Typically, most samples will be
fully cooled to the freezer set temperature within no more than
five hours. In most cases, it is contemplated that the input/output
buffer section will constitute part of one of the freezer bays, and
the remaining section of that freezer bay will be used for
long-term storage of samples. In that case, it is desirable that
the temperature sensor for the refrigeration unit be located within
the input/output buffer section of the freezer bay which is
normally the section closer to the refrigeration unit. Testing has
shown that such a configuration will cause the refrigeration unit
to operate more aggressively to prevent temperature rise within the
freezer bay that could otherwise affect samples outside of the
input/output buffer section.
[0006] The preferred input/output module is designed to work in
connection with the cassette puller described in co-pending U.S.
patent application Ser. No. ______, filed on even date herewith,
entitled "Cassette Puller", Attorney Docket No. 5436-00018, and
incorporated herein by reference. The input/output module holds
multiple cassettes for transferring samples stored in tube storage
racks or plates into the refrigerated enclosure from outside of the
system and also for transferring samples from inside of the
refrigerated enclosure to outside of the system. The most efficient
use of the system is with specific input/output cassettes that are
preferably configured so that the cassette puller in the above
incorporated patent application is able to transfer the
input/output cassettes within the refrigerated enclosure to and
from the input/output module and to and from the above described
input/output buffer section in the freezer. It is also preferred
that the cassette puller be able to eject tube storage racks or
plates from the input/output cassettes or place sample tube storage
racks or plates onto shelves on the input/output cassettes.
Preferably, this is done in essentially the same manner that the
cassette puller places racks or plates in or ejects racks or plates
from a storage cassette used for long-term sample storage in the
ultra-low temperature or cryogenic freezers. The preferred
configuration for the storage cassette is described in co-pending
patent application Ser. No. ______, filed on even date herewith,
entitled "Sample Storage Cassette for Ultra-Low or Cryogenic
Temperatures", Attorney Docket No. 5436-00019, and incorporated
herein by reference.
[0007] The input/output module includes a manual loading/unloading
station that provides a central interface for a user working with
the system on an everyday basis. It is desirable that the
input/output module be able to accommodate the introduction and
removal of a low number of samples, e.g. 20 tubes in a single SBS
tube rack or a higher number of samples, e.g. 10,000 tubes in
roughly 100 SBS tube racks, as well as bulk introduction and
removal of samples. The introduced samples can be warm, for example
when arriving from a processing laboratory or alternatively the
samples can be cold or ultra-cold such as when arriving on dry ice
from a distant laboratory. When introducing ultra-cold samples, the
system is desirably operated to minimize temperature rise of the
introduced samples during the sample introduction process. On the
other hand, when warm samples are introduced to the system, the
system is desirably operate to protect the thermal integrity of
samples already stored and minimize temperature rise of previously
stored samples.
[0008] The preferred input/output module is located within the
refrigerated chamber and includes carousel with multiple insulated
sleeves that hold input/output cassettes. The exemplary carousel
includes eight sleeves for holding eight separate input/output
cassettes, although the number of sleeves can be more or less as
the application requires. As the carousel is rotated, one of the
indexing positions (loading/unloading position) corresponds to a
loading/unloading station which is located adjacent an opening
through the enclosure wall. At least one door or set of doors
covers the opening. Optionally, an air purge system is provided to
prevent moisture from encroaching through the input/output module
into the refrigerated enclosure when samples are being loaded or
unloaded. The door or set of doors is opened to provide access for
a user located outside of the refrigerated enclosure to shelves on
an input/output cassette located at the loading/unloading position
on the carousel. Sample tube storage racks or plates are manually
placed by the user on the respective shelves in the input/output
cassette to load the system. Once the cassette is filled, the
carousel rotates or indexes to the next position allowing the user
to fill another input/output cassette if necessary. One of the
other carousel indexing positions serves as a designated cassette
transfer position and corresponds to the location that the cassette
puller removes filled input/output cassettes from the carousel and
places empty input/output cassettes into the carousel. The cassette
puller transfers filled input/output cassettes to the input/output
buffer section in the designated freezer bay as described above. On
the other hand, it is preferred that the empty input/output
cassettes placed into the insulated sleeves on the carousel be
pre-cooled in the input/output buffer section in the designated
freezer. In the case that the loaded samples are cold or ultra-cold
samples, it is preferred that the carousel rotates 180.degree. from
the loading/unloading position to the designated cassette transfer
position once the input/output cassette is loaded without stopping
at any intermediate indexing positions. The direct 180.degree.
rotation to the designated cassette transfer position speeds the
transfer of cold or ultra-cold samples to the cassette puller and
eventually into the input/output buffer section of the designated
freezer bay. Of course, the input/output module can be used to load
and unload either warm or cold samples in process sequences other
than described above if desired.
[0009] In another aspect of the invention, the input/output
cassette is designed specifically to accommodate manual loading and
unloading of samples. In this regard, the shelves on the
input/output cassette extend forward beyond the sidewalls in the
portion of the cassette in which samples are loaded and unloaded,
thereby facilitating convenient access even with gloved fingers. In
addition, the distance between the shelves is increased compared to
a typical storage cassette. Further, storage cassettes may
typically be about six feet tall, and it is desirable that the
overall height of the input/output cassette be the same as the
storage cassette to enable the cassette puller to effectively
retrieve both types of cassettes from the freezer bays. On the
other hand, it is not convenient for users to load samples below
the height of their thigh or above the height of their shoulder.
Therefore, in accordance with this aspect of the invention, the
input/output cassettes include a sample storage portion that will
typically be about three feet long and stand at a height off the
ground to a height range corresponding to a typical user's thigh to
shoulder. The sample storage portion of the input/output cassette
has a plurality of generally spaced shelves, each for holding
sample tube storage racks or plates. The input/output cassettes
also include a top plate and a bottom plate. However, an upper
portion of the input/output cassette spanning between the sample
storage portion and the top plate is not intended to hold sample
storage tube racks or plates. Likewise, a lower portion that is not
intended to hold sample tube racks or plates spans between the
bottom of the sample storage portion and a bottom plate. Desirably,
the input/output cassette includes the same or at least compatible
top plate and retrieval catch as the storage cassette as well as
same or compatible guide legs on the bottom of the cassette so that
the overall size and footprint of the input/output cassette is the
same as or quite similar to the storage cassettes. This enables the
input/output cassettes to be fully compatible with the cassette
puller and nesting tubes in the freezer bays.
[0010] Another advantage of the invention is that the storage
cassettes for long term storage of the samples can also, in the
preferred system, fit into the sleeves in the input/output module,
thereby enabling the storage cassettes to be removed from the
system for maintenance of the storage cassettes or to substitute
storage cassettes in the system with cassettes sized for different
storage racks or plates. In the exemplary embodiment, shields cover
the top and lower portion of the sleeves, but these sleeves can be
made removable to facilitate the transfer of a storage cassette
into and out of the system through the input/output module.
[0011] It should also be noted that the storage cassettes in some
systems can be shorter than about 6 feet tall, for example about
31/2 feet tall. In such a system, the input/output cassette
described above does not require an upper portion that is not
intended to hold sample storage tube racks or plates, but may very
well include a lower portion that is not intended to hold sample
tube racks or plates.
[0012] Other features and advantages of the invention may be
apparent to those skilled in the art upon reviewing the following
drawings and description thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a perspective view of a refrigerated enclosure
maintained for example at -20.degree. C. of the type in which the
invention operates.
[0014] FIG. 2 is a perspective view of an automated storage and
retrieval system located within the refrigerated enclosure shown in
FIG. 1.
[0015] FIG. 3 is a sectional view taken along line 3-3 in FIG. 1
illustrating an input/output module and a thermally segregated
input/output buffer in a freezer chest as in accordance with an
exemplary embodiment of the invention.
[0016] FIG. 4 is a perspective view of an input/output module
located within the refrigerated enclosure that is being engaged by
a cassette puller within the enclosure as in accordance with the
exemplary embodiment of the invention.
[0017] FIG. 5 is a detailed perspective view of an input/output
module constructed in accordance with the exemplary embodiment of
the invention.
[0018] FIGS. 6A and 6B are sectional views showing the loading of
samples into the input/output module. FIG. 6A illustrates the
preferred method when loading warm samples. FIG. 6B illustrates the
preferred method when loading cold or ultra-cold samples.
[0019] FIG. 7 is a longitudinal sectional view of the input/output
module illustrating input/output cassettes residing within
insulated sleeves on the carousel of the input/output module.
[0020] FIG. 8 is a sectional view taken along line 8-8 in FIG.
7.
[0021] FIG. 9 is perspective view showing an input/output cassette
residing within an insulated sleeve normally attached to the
carousel of the input/output module.
[0022] FIG. 10 is a view showing the input/output cassette removed
from the sleeve.
[0023] FIG. 11 is a detailed assembly drawing of portions of the
input/output cassette constructed in accordance with the exemplary
embodiment of the invention.
[0024] FIG. 12 plots temperature rise data for samples previously
stored in a -80.degree. C. freezer when warm samples are also
placed into the freezer.
[0025] FIG. 13 is a schematic drawing illustrating the experimental
setup underlying the data plotted in FIGS. 12 and 14.
[0026] FIG. 14 plots additional temperature data pertaining to the
experiment shown schematically in FIG. 13.
DETAILED DESCRIPTION
[0027] FIG. 1 illustrates the outside of a refrigerated enclosure
10 maintained at a temperature of approximately -15.degree. C. to
-30.degree. C., preferably about -20.degree. C. FIG. 2 shows an
automated storage and retrieval system 12 for storing sample tube
racks or plates at an ultra-low or cryogenic temperature located
within the refrigerated enclosure 10. A sample input/output module
14 is located inside the refrigerated enclosure 10 along its front
wall adjacent an opening 16 (FIG. 3) covered by a door 18 or a set
of doors. FIGS. 1 and 2 illustrate in phantom that it may desirable
for the system to include a second input/output module. In FIGS. 1
and 2, the input/output modules are located along a front wall 20
of the refrigerated enclosure 10, however depending on the
application it may desirable to locate the input/output module 14
along a sidewall 22 of the refrigerated enclosure 10, for example
in the location of the full length door shown in FIGS. 1 and 2.
Multiple horizontal freezer chests 11 are located within the
refrigerated enclosure 10 and each storage compartment or freezer
bay is maintained at a temperature setting at or below -65.degree.
C. under normal operating conditions. Preferably, each freezer
chest 11 contains two independently cooled bays. Biological or
chemical samples stored in sealed storage tubes held in tube racks
or stored in sealed wellplates are stored within the freezer chest
11 for long term storage. In an ultra-low temperature system, the
temperature setting within the freezer chest 11 will be maintained
at for example -80.degree. C. In a cryogenic system, the
temperature within the chest 11 may be maintained at a temperature
as low as -196.degree. C. Refrigeration units 13 for the respective
freezer chests 11 are located on the exterior of the refrigerated
enclosure 10. The size of the refrigerated enclosure 10 as well as
the number of freezer chests 11 within the refrigerated enclosure
10 and the requisite refrigeration units 13 can be expanded in
order to accommodate the storage needs of the facility.
[0028] The refrigerated enclosure 10 provides a low temperature
(-15.degree. C. to -30.degree. C., e.g., -20.degree. C.) work space
for the automated storage and retrieval system 12. The automated
storage and retrieval system 12 is mounted to a traveling gantry 24
that is driven linearly along horizontal Y-axis rails 26. The
gantry 24 moves over and above the top of the freezer chest 11 and
also over and above the input/output module 14. The system 12
includes a robotic cassette puller 28 which moves with the gantry
24, thus providing the cassette puller 28 with access to storage
cassettes or input/output cassettes stored in the freezers 11 and
input/output cassettes residing in the input/output module 14. The
invention is not limited to the specific configuration of the
cassette puller 28. Nevertheless, it is preferred that the cassette
puller be constructed in accordance with the description of
co-pending U.S. patent application Ser. No. ______, entitled
"Cassette Puller", Attorney Docket No. 5436-00018, filed on even
date herewith and incorporated herein by reference.
[0029] Referring now to FIG. 3, an array of storage cassettes 30 is
stored in the bays of the freezer chest 11. The storage cassettes
30 carry samples stored in tube storage racks or plates for the
purpose of transporting the racks or plates to a long term storage
location and for storing the racks or plates in the long term
storage location. It is desirable that the freezer chest 11 contain
a nest, preferably an integral array of aluminum nesting tubes, for
separating and guiding the placement of the cassettes 30 into the
freezer compartments. It is preferred that the storage cassette and
nesting configuration within the freezer bay be constructed in
accordance with the description of co-pending U.S. patent
application Ser. No. ______, entitled "Sample Storage Cassette for
Ultra-Low or Cryogenic Temperatures", Attorney Docket No.
5436-00019, filed on even date herewith and incorporated herein by
reference. Each freezer chest 11 includes at least one lid 32 that
must be removed in order to access the cassettes 30 within the
respective freezer bay. Normally, the freezer chest 11 will have
two lids 22 so that removal of one of the lids 22 will provide
access to one bay in the freezer and removal of the other lid will
provide access to the other bay in the freezer 11. As shown in FIG.
3, a large conduit 34 passes through the wall of 22 of the
refrigerated enclosure 10 and provides a passage for refrigerant
lines to the freezer chest 11 from the refrigeration unit 13.
[0030] In FIG. 3, the lid is removed from a first bay 35 in the
freezer 11. A lid 32 covers a second bay 37 (shown in phantom) in
the freezer chest 11. Referring in particular to the first
uncovered bay 35, an insulated wall 40 thermally segregates the bay
35 into two sections 36, 38. The thermally segregated section 38
closest to the refrigeration unit 13 is an input/output buffer
section 38 and serves the primary purpose of temporarily storing
input/output cassettes when samples are loaded into the system. The
samples are stored in the input/output buffer section 38 preferably
until the samples are ensured to be cooled to the temperature
setting for the freezer, i.e. about -80.degree. C. in an ultra-low
temperature system. It is expected that holding the samples in the
input/output buffer section 38 for a period of five hours will
ensure that all samples stored in the input/output buffer section
38 have been appropriately cooled. As will be described in more
detail later, in normal operation, only input/output cassettes 44
are stored in the input/output buffer section 38. It is desirable
that all samples be transferred to storage cassettes 30 for long
term storage.
[0031] Referring briefly to FIG. 2, once the samples in an
input/output cassette 44 have been suitably cooled in the
input/output buffer section 38 of the freezer 11, the cassette
puller 28 removes the input/output cassette 44 and in turn ejects
each rack or plate held in the input/output cassette 44. The rack
or plate is then processed by the system 12, for example by
identifying the samples using a barcode identification station 48
and/or processing the samples held in a tube storage rack in a tube
picking mechanism 46. Then the samples are placed onto an open
shelf in a storage cassette 30 and the cassette puller 28 places
the storage cassette 30 in an appropriate location for long term
storage of the sample.
[0032] Referring now to FIGS. 12-14, experiments were run to
determine the significance of thermally segregating warm samples
placed into a freezer and the effect that the warm samples had on
the temperature of samples previously stored and cooled to
-80.degree. C. FIG. 13 shows the experimental setup which included
a freezer 48 cooled at or near -80.degree. C. and a controller 50.
A small nest 52 of aluminum nesting tubes was placed in the freezer
48 and held a cassette 54 that contained an instrumented sample
tube in a tube storage rack. A temperature sensor measured the
temperature of the sample in the rack over time. Bottles 56
containing two liters total of room temperature water were placed
in the freezer 48. FIG. 13 shows insulation 58 located between the
bottles 56 of room temperature water and the cassette 54 containing
the cold -80.degree. C. samples and temperature sensor. The
experiment was also run without the insulation 58 present.
Referring to the data shown in FIG. 12, the temperature rise of the
previously stored -80.degree. C. samples is substantial when the
room temperature water was added to the system and there is not
insulation 58. The temperature rise indicates that the -80.degree.
C. sample will rise between about 3.degree. C. and 7.5.degree. C.
within one hour and that the temperature rise will peak between an
hour and two hours. The data in FIG. 12 also indicated that there
continues to be significant temperature rise even after the room
temperature water bottles 56 were stored in the system for three
hours. On the other hand, when the insulation 58 is present and the
room temperature water bottles 56 are thermally segregated from the
remaining portions of the freezer 48, the detected temperature rise
is less than 2.degree. C. The data in FIG. 12 was taken in a system
in which the thermostat for the freezer 48 was located on the side
of the freezer near the instrumented rack 54 and removed from the
room temperature water bottles 56. Even under this scenario the
temperature rise in the -80.degree. C. sample as measured in the
instrumented rack was minimal when there was insulation. FIG. 14
shows representative data of temperature change in the instrumented
rack containing water filled storage tubes at -80.degree. C. when
the room temperature water bottles 56 are placed on the side of the
insulation 58 in the freezer compartment 48 that the freezer
thermostat is located. Under this scenario, the room temperature
water bottles 56 drive the temperature in the vicinity of the
thermostat upwards causing the refrigerator compressor to run
continuously until the water bottles are fully cooled or near fully
cooled. The data in FIG. 14 shows that the temperature in the
instrumented rack actually drops below its original -80.degree. C.
temperature under this scenario. In fact, for the first six hours
the temperature of the instrumented rack 54 continued to drop
significantly and only recovered after the water in the bottles 56
were sufficiently cold to no longer trigger compressor
operation.
[0033] Referring again to FIG. 3, it is contemplated that in most
systems the input/output buffer section 38 will constitute only a
relatively small portion of one of the freezer bays. The thermally
insulated wall 40 can take the form of foam insulation. The
location of the thermally insulated wall 40 can be adjusted to
enlarge the size of the input/output buffer section 38 if
necessary, and in some applications it may even be desirable to
designate an entire freezer bay as an input/output buffer section.
Note, however, that it would not normally be desirable to provide
separate input/output buffer sections in two different freezer
bays. In FIG. 3, nesting tubes have been removed to make room for
the thermally insulating wall 40. As mentioned, a practical
alternative is to leave the complete nest 46 intact as described in
the above incorporated patent application entitled "Storage
Cassette", and fill selected nesting tubes with insulation to form
a thermally segregating barrier between the input/output buffer
section 38 and the long term storage section 36.
[0034] Still referring to FIG. 3, the exemplary input/output module
14 includes eight cassette bays in the form of vertical sleeves 70
which are shown in FIG. 3 to be located in distinct indexing
positions labeled with reference numbers 62A-62H. The sleeves 70
are attached to a carousel 60 that is located within an insulated
box 64 inside the refrigerated enclosure 10. In the embodiment
illustrated in the drawings, cassette sleeve 70 on the carousel 60
in the position labeled 62A is in the loading/unloading position
and cassette sleeve 70 in the position labeled 62E is in the
designated cassette transfer position. The cassette puller 28
transfers input/output cassettes 44 to and from the input/output
module 14 by placing the input/output cassettes 44 or removing the
input/output cassettes 44 from the sleeve 70 located at position
62E. The user of the system manually loads or unloads samples into
a cassette 44 located in the sleeve 70 located at the
loading/unloading position 62A.
[0035] Referring to FIGS. 4 and 5, the insulated box 64 surrounding
the input/output module 14 has been removed to show the internal
components. FIGS. 4 and 5 show input/output cassettes 44 loaded
into vertical sleeves 70 on the carousel 60. In order to place or
retrieve a cassette from the input/output module 14, the cassette
puller 28 is positioned over port 66E in the top plate 68 of the
input/output module 14 which is above the sleeve 70 in the
designated cassette transfer position 62E. The top plate 68 of the
input/output module 14 includes ports 66C and 66G for the cassette
puller 28 that are located over the sleeves 70 positioned at
indexing positions 62C and 62G in addition to the port 66E over the
sleeve 70 in position 62E. Position 62E is 180.degree. opposite
from position 62A corresponding to the loading/unloading station.
In most applications, the ports 66E and 66G (corresponding to the
90.degree. and the 270.degree. indexing positions) will be covered.
It is desirable that the cassette puller 28 place cassettes 44 into
and remove cassettes 44 from a single designated cassette transfer
location. The ports 66C and 66G at the 90.degree. and the
270.degree. indexing positions are used in the event that the
input/output module 14 is located near the corner of the
refrigerated enclosure 10.
[0036] The preferred methods of loading samples into the system
using the input/output module 14 is now discussed in connection
with FIGS. 6A and 6B. FIG. 6A describes the procedure that will
typically be used when loading a large number of warm samples into
the system. FIG. 6A shows input/output cassettes 44 being located
in each of the insulated sleeves 70 on the carousel 60; however the
cassettes in positions 62F, 62G and 62H are empty. As a first step,
an empty input/output cassette 44 is placed in the sleeve 70
located at position 62E corresponding to the designated cassette
transfer location. (FIG. 6A shows a loaded cassette 44 at position
62E which corresponds to a subsequent step in the process.) The
input/output cassette 44 is preferably pre-cooled to -80.degree. C.
in the input/output buffer section 38 of freezer bay 35 prior to
loading the empty cassette 44 into the sleeve 70 at position 62E.
The carousel 60 is then rotated to present the input/output
cassette 44 to the loading/unloading station at position 62A. When
warm samples are being loaded, and especially a large number of
warm samples, it is normally be sufficient to index the carousel 60
one position at a time to introduce the next empty cassette 44 to
the loading/unloading position 62A. Once an empty cassette is
presented at the loading/unloading position 62A, the system doors
18 are opened. FIG. 6A shows an internal door 74 which is optional.
If present, the internal door 74 is opened as well to provide the
user access to the empty input/output cassette 44 on the carousel
60 at the loading/unloading position 62A. Optionally, the system
can provide an air purge, when the doors 18 are opened, to prevent
or mitigate moisture from encroaching from outside of the
refrigerated enclosure 10 into the input/output module 14 and
eventually inside of the enclosure 10. With the doors open, the
user manually loads tube storage racks 72 or plates into shelves on
the input/output cassette 44 at the loading/unloading station 62A.
FIG. 6A shows the rack 72 loaded into the input/output cassette 44
at the loading/unloading position 62A. The doors 18 are then closed
and the carousel 60 is indexed to present the next sleeve 70 to the
loading/unloading position 62A. The above steps are repeated as
necessary to accommodate all of the samples that need to be loaded
into the system. When the carousel 60 rotates so that a loaded
input/output cassette 44 is presented at the designated cassette
transfer position 62E, the cassette puller 28 lifts the loaded
input/output cassette 44 and transfers it to the input/output
buffer section 38 in the freezer bay, see FIG. 3. Normally, the
loading and unloading of tube storage racks and/or plates at the
loading/unloading position 62A is accomplished by placing
individual racks or plates on individual shelves. In some
applications, however, it may be desirable to modify the
input/output cassette 44 to include a removable module of multiple
shelves which can be preloaded with tube storage racks or plates
prior to loading the samples into the input/output cassette when it
is located at the loading/unloading station 62A.
[0037] FIG. 6B illustrates the preferred method of loading cold or
ultra-cold samples into the system. In this method, it is only
necessary to include input/output cassettes 44 in two sleeves 70
preferably disposed 180.degree. from each other in the
loading/unloading position 62A and in the designated cassette
transfer position 62E. Again, it is desired that the input/output
cassettes 44 be pre-cooled in the input/output buffer section 38
prior to loading the empty cassettes 44 into the respective sleeve
70 in the input/output module 14. Once the empty, pre-cooled
input/output cassette 44 is placed into the appropriate carousel
sleeve 70, the carousel rotates 180.degree. to present the empty,
pre-cooled cassette 44 at the loading/unloading position 62A. The
doors 18 (and optional door 74) are opened and the user loads cold
or ultra-cold sample tube storage racks 72 or plates into the
input/output cassette 44 at loading/unloading position 62A. Once
the cassette is loaded, the doors are closed and the carousel is
rotated 180.degree.. Prior to the 180.degree. rotation, however,
another empty, pre-cooled cassette 44 is loaded into the sleeve 70
at the designated cassette transfer position 62E. The 180.degree.
rotation therefore simultaneously positions a loaded cassette 44 at
the designated cassette transfer location 62E which is ready for
removal by the cassette puller 28 to the input/output buffer
section 38 and positions an empty, pre-cooled cassette 44 at the
loading/unloading position 62A. This procedure is repeated as
necessary to accommodate all of the cold or ultra-cold samples that
need to be loaded into the system.
[0038] Referring to now FIG. 7, the carousel 60 includes a carousel
frame 76 that is mounted on a turntable 78. The vertical sleeves 70
are attached to the carousel frame 76. A central pedestal 80 is
attached to the floor 82 of the input/output module 14. The
carousel motor 84 is mounted to the pedestal 80 and drives a
universal joint 86 connected to the turntable 78 to rotate the
carousel frame 76 and sleeve 70. A homing sensor 88 is mounted to
the pedestal 80 and detects the position of the carousel 60,
particularly when it is necessary to determine the home position of
the carousel 60. FIG. 7 shows input/output cassettes 44 located in
two of the insulated sleeves 70 attached to the carousel frame 76.
FIG. 7 also illustrates a rack 72 in phantom being loaded into the
cassette 44 located near the opening 90 in the front wall of the
refrigerated enclosure 10. FIG. 8 is a sectional view taken along
line 8-8 in FIG. 7 and illustrates a rack 72 loaded onto a cassette
shelf 44 contained within the insulated sleeve 70. It also shows
the cross section of a mounting bracket 91 used to mount the
illustrated insulated sleeve 70 to the carousel frame 76.
[0039] Referring to FIGS. 9-11, the exemplary input/output cassette
44, as mentioned, is preferably designed to have the same height as
the storage cassettes 30 used for long term storage in the system.
However, as mentioned, the input/output cassettes 44 are configured
for loading and unloading samples only over a portion of their
height which is convenient for loading and unloading by the normal
user of the system. In particular, the input/output cassette 44
includes a sample storage portion 92 as well as an upper portion 94
and a lower portion 96 which are not intended to hold sample tube
storage racks or plates. The cassette 44 also includes a top plate
98 and a bottom plate 100. The upper portion 94 spans between the
top end of the storage sample portion 92 and the top plate 98,
whereas the lower portion 96 spans between the lower end of the
sample storage portion 92 and the bottom plate 100. The top portion
94 as well as the top plate 98 is preferably constructed in a
manner similar or identical to the corresponding structure in a
storage cassette 30, such as described in the above incorporated
patent application entitled "Storage Cassette." Likewise, the
bottom end of the input/output cassette 44 including the lower
portion 96 and tapered feet 102 are preferably constructed in a
manner similar or identical to the corresponding portion of the
storage cassette described in the above incorporated patent
application entitled "Storage Cassette." The vertical sleeves 70
into which the input/output cassettes 44 are placed on the
input/output module 14 preferably have insulated walls 104 on three
sides, and also desirably includes shields 106, 108 corresponding
to the location of the upper portion 94 and lower portion 96 of the
input/output cassette 44. The shields 106, 108 help to prevent
convective heat transfer. Note that the top 68 (FIG. 5) of the
input/output module 14 covers the top of the sleeve 70 unless the
sleeve 70 is located at the designated cassette transfer station
(position 62E in FIGS. 6A and 6B). As can be seen in FIG. 10, the
compartments in the sample storage portion 92 of the input/output
cassette 44 are slightly taller than the height that the
compartments would normally be in a storage cassette 30. In
addition, the compartment shelves 112 in the sample storage section
92 extend a forward beyond the sidewall 110 which facilitates
accessibility with gloved fingers.
[0040] It is desirable that the shields 106, 108 on the vertical
sleeves 70 in the input/output module 14 be removable by a user
outside of the system so that a full cassette 44, 30 in the sleeve
70 can be removed from or placed into the system. By removing the
shields 106, 108 both input/output cassettes 44 and storage
cassettes 30 can be removed from or placed into the system which
can be particularly beneficial for maintenance. Further, it is
convenient way to replace a storage cassette 30 with one having
different shelf spacing. It is likely that users will find it
convenient to load or unload full input/output cassettes 44 into a
sleeve 70 (with the shields 106, 108 removed or nonexistent) under
normal operation of the system, although it is possible.
[0041] Referring in particular to FIG. 11, the shelves 112 are
preferably closed shelves to help prevent convective air flow
through the input/output cassette 44. The shelves 112 desirably
include lips 114 on the front edge to help prevent racks or plates
from sliding off of the shelf 112 when the cassette 44 is moved. In
addition, the front edge of the shelf 112 includes an indentation
116 that provides clearance for lifting fingers on the ejector
mechanism for the cassette puller 28. This indentation 116 allows
for an optical sensor to detect whether any racks have been loaded
into the cassette 44 or whether all racks have been unloaded from
the cassette 44. The shelves 112 are preferably made of aluminum
and form part of a plate that also includes a reference positioning
stop 118. The reference positioning stop 118 is used by the
cassette puller 28 to mechanically reference the respective shelf
112 at the appropriate height in the cassette puller 28 for
ejection of a rack or plate from the shelf 112 or for placement of
a rack or plate onto the shelf 112 as described in connection with
the above incorporated patent application entitled "Cassette
Puller." It also provides mechanical means for the cassette puller
28 to lock the input/output cassette 44 in place in the cassette
puller 28 when transferring the input/output cassette 44 from or to
the input/output module 14 or otherwise. FIG. 11 illustrates the
assembly of the input/output cassette 44 and in particular that the
shelves 112 and the sample storage portion 92 are connected
together with wires and are held in the appropriate vertical
location via openings 120 in the plastic sidewall 110. FIG. 11 also
shows that the sample storage portion 92 is attached to the upper
and the lower portions 94, 96 by connecting the wires with brackets
to the upper and lower 94, 96 portions respectively.
[0042] In the foregoing description, certain terms have been used
for brevity, clearness, and understanding. No unnecessary
limitations are to be inferred therefrom beyond the requirement of
the prior art because such terms are used for descriptive purposes
and are intended to be broadly construed. The different
configurations, systems, and method steps described herein may be
used alone or in combination with other configurations, systems and
method steps. It is to be expected that various equivalents,
alternatives and modifications are possible within the scope of the
appended claims.
* * * * *