U.S. patent application number 13/005086 was filed with the patent office on 2011-08-18 for double-door vertical freezer.
This patent application is currently assigned to Angelantoni Industrie SPA. Invention is credited to Maurizio Ascani, Dario De Angelis.
Application Number | 20110197623 13/005086 |
Document ID | / |
Family ID | 42668619 |
Filed Date | 2011-08-18 |
United States Patent
Application |
20110197623 |
Kind Code |
A1 |
Ascani; Maurizio ; et
al. |
August 18, 2011 |
DOUBLE-DOOR VERTICAL FREEZER
Abstract
The present invention relates to a freezer 10 of the very low
temperature vertical type. The freezer 10 comprises: a thermally
insulating cabinet 12 comprising in turn two side walls 14 and 16,
an upper wall 18, a lower wall 20 and a rear wall 22; a thermally
conducting shelf 24 suitable for defining, inside the cabinet, an
upper compartment 26 and a lower compartment 28; an upper door 30
for closing the upper compartment 26; and a lower door 32 for
closing the lower compartment 28. The freezer comprises a single
cooling plant 34 designed to cool the upper compartment and the
lower compartment. Moreover, the thermally conducting shelf defines
an air-tight closure between the upper compartment and the lower
compartment. Finally, the cooling plant comprises a coil circuit 36
running through the upper wall, the side walls and the rear wall of
the cabinet. The coils are distributed with a variable density
along the height of the cabinet.
Inventors: |
Ascani; Maurizio; (Massa
Martana (PG), IT) ; De Angelis; Dario; (Perugia,
IT) |
Assignee: |
Angelantoni Industrie SPA
Massa Martana (PG)
IT
|
Family ID: |
42668619 |
Appl. No.: |
13/005086 |
Filed: |
January 12, 2011 |
Current U.S.
Class: |
62/441 |
Current CPC
Class: |
F25D 23/061 20130101;
F25D 11/02 20130101 |
Class at
Publication: |
62/441 |
International
Class: |
F25D 11/04 20060101
F25D011/04 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 12, 2010 |
IT |
MI2010A 000220 |
Claims
1-14. (canceled)
15. A very low temperature vertical freezer, comprising: a
thermally insulating cabinet comprising two side walls, an upper
wall, a lower wall, and a rear wall; a thermally conducting shelf
suitable for defining, inside said cabinet, an upper compartment
and a lower compartment; an upper door for closing the upper
compartment; a lower door for closing the lower compartment;
wherein the freezer comprises a single cooling plant designed to
cool the upper compartment and the lower compartment; the thermally
conducting shelf forms an air-tight closure between the upper
compartment and the lower compartment; and the cooling plant
comprises a coil circuit running through the upper wall, the side
walls, and the rear wall of the cabinet, coils of the coil circuit
being distributed with variable density along a height of the
cabinet.
16. The freezer according to claim 15, wherein volume of the upper
compartment is smaller than or equal to volume of the lower
compartment, and wherein extension of the coils around the upper
compartment is greater than or equal to the extension of the coils
around the lower compartment.
17. The freezer according to claim 15, wherein the cooling plant is
designed to cool the upper and lower compartments to a temperature
of between -40.degree. C. and -80.degree. C.
18. The freezer according to claim 15, wherein the coils are
distributed in the walls bounding the upper compartment with a
greater average density than in the walls bounding the lower
compartment.
19. The freezer according to claim 15, wherein the upper wall has a
density of the coils greater than density of the coils in the side
walls and in the rear wall.
20. The freezer according to claim 15, wherein the coils are
distributed in the side walls and in the rear wall in such a way so
as to have an almost constant average density along a section
bounding the upper compartment and in such a way so as to have a
variable density along the section bounding the lower
compartment.
21. The freezer according to claim 20, wherein density of the coils
increases from bottom to top of the lower compartment.
22. The freezer according to claim 15, wherein 54% of total of the
coils extend around the upper compartment and remaining 46% of the
total of the coils extend around the lower compartment.
23. The freezer according to claim 15, wherein the air-tight
closure between the upper compartment and the lower compartment is
obtained by means of a silicone bead.
24. The freezer according to claim 15, wherein overall inner volume
of the freezer is divided up differently between the upper
compartment and the lower compartment.
25. The freezer according to claim 24, wherein volume of the upper
compartment is about 45% of total volume cooled by the freezer,
while volume of the lower compartment is about 55% of the total
volume cooled by the freezer.
26. The freezer according to claim 15, wherein the upper door and
the lower door are identical to each other.
27. The freezer according to claim 15, further comprising a
thermally insulating band between the two upper and lower doors,
the shelf having a smaller thickness than the band and being
mounted above, flush with the band.
28. The freezer according to claim 15, further comprising control
means for allowing separate access to the upper and lower
compartments.
Description
[0001] The present invention relates to a double-door vertical
freezer, in particular a very low temperature freezer.
[0002] It is known, for example in the sector of scientific
laboratories, to use very low temperature freezers, i.e. freezers
which are suitable for maintaining internally temperatures of
between -40.degree. C. and -80.degree. C.
[0003] These freezers may have different configurations, for
example may have a substantially horizontal or substantially
vertical extension. This latter configuration offers the advantage
that, for the same useful internal volume, its occupies a smaller
floor area.
[0004] There exist furthermore some configurations which envisage a
single refrigerated compartment closed by a single door, while
other configurations envisage two separate compartments which are
closed by two independent doors. This latter configuration is able
to limit the problems associated with the variations in temperature
which are recorded inside the refrigerated compartments upon
opening the door. The double door and the double internal
compartment allow, for example, separation of the samples which
must be stored for a long period of time from those which must be
stored for a shorter period of time. In this case, the latter
samples may be placed in the compartment where the door is opened
more frequently, while the other samples may be kept in an
environment which comes into contact with the exterior less
frequently and therefore is less exposed to variations in
temperature.
[0005] Moreover, the double door allows, by means of the use of
keys or other means for controlling access, two different users to
have a specific dedicated space, without the activity of one
interfering with the activity of the other one.
[0006] The configuration described above of the double-compartment
and double-door vertical freezer is at present achieved by means of
two different constructional designs. These constructional designs,
although widely used, are however not without drawbacks.
[0007] A first constructional design envisages the substantial
arrangement on top of one another, within a single cabinet, of two
different freezers which are independent of each other. In this
design, therefore, there is a clear duplication of the plants and
apparatus associated with cooling of the internal compartments.
This obviously results in a substantial increase in the freezer
production and operating costs.
[0008] A second constructional design envisages instead the
division, into two, of the internal compartment and of the door of
a conventional vertical freezer. This design envisages that, in
order to ensure a temperature of the two compartments which is as
uniform as possible, a communication channel between the two
compartments is maintained so that it is possible to establish an
airflow between one compartment and the other one. This
communication channel between the two compartments constitutes a
potential path via which the samples stored in the upper
compartment and the samples stored in the lower compartment may
contaminate each other.
[0009] The object of the present invention is therefore to overcome
at least partly the drawbacks mentioned above with reference to the
prior art.
[0010] In particular, one task of the present invention is to
provide a double-door freezer which ensures complete isolation
between the upper compartment and the lower compartment and which
at the same time ensures temperatures which are substantially the
same in both compartments.
[0011] Another task of the present invention is to provide a
double-door freezer which is able to ensure lower production and
operating costs.
[0012] The abovementioned object and tasks are achieved by a
double-door freezer according to claim 1.
[0013] The characteristic features and further advantages of the
invention will emerge from the description provided hereinbelow, of
some examples of embodiment, provided by way of a non-limiting
example, with reference to the accompanying drawings in which:
[0014] FIG. 1 shows a first perspective view of a freezer according
to the invention;
[0015] FIG. 2 shows a second perspective view of a freezer
according to the invention;
[0016] FIG. 3 shows a third perspective view of a freezer according
to the invention where the doors have been removed for greater
clarity;
[0017] FIG. 4 shows a transparent perspective view of a freezer
according to the invention in which part of the cooling plant is
shown.
[0018] With reference to the accompanying figures, 10 denotes in
its entirety a very low temperature vertical freezer according to
the invention. The freezer 10 comprises: [0019] a thermally
insulating cabinet 12 comprising in turn two side walls 14 and 16,
an upper wall 18, a lower wall 20 and a rear wall 22; [0020] a
thermally conducting shelf 24 suitable for defining, inside the
cabinet 12, an upper compartment 26 and a lower compartment 28;
[0021] an upper door 30 for closing the upper compartment 26; and
[0022] a lower door 32 for closing the lower compartment 28.
[0023] The freezer 10 according to the invention comprises a single
cooling plant 34 designed to cool the upper compartment 26 and the
lower compartment 28.
[0024] Moreover, the thermally conducting shelf 24 defines an
air-tight closure between the upper compartment 26 and the lower
compartment 28. Finally, the cooling plant 34 comprises a coil
circuit 36 running through the upper wall 18, the side walls 14 and
16 and the rear wall 18 of the cabinet 12. The coils 36 are
distributed with a variable density along the height of the cabinet
12. In connection with the present description the expression "very
low temperature", as conventionally used in the sector, is
understood as meaning a temperature of between -40.degree. C. and
-80.degree. C.
[0025] The density of the coils 36 may be defined in various
manners, for example as the ratio between the overall length of the
linear extension of the coils which travel along a wall and the
area of the wall itself. As the person skilled in the art may
easily understand, this definition may be applied also to surfaces
smaller than the entire wall, but cannot be meaningfully applied if
the surfaces in question are very small.
[0026] According to one embodiment of the freezer 10, the coils 36
are distributed so as to achieve a greater average density in the
walls which bound the upper compartment 26 than in the walls which
bound the lower compartment 28. In particular, the upper wall 18
has preferably a greater density than the side walls 14 and 16 and
the rear wall 22.
[0027] According to some embodiments of the freezer 10, the volume
of the upper compartment 26 is smaller than or equal to the volume
of the lower compartment 28 and the extension of the coils around
the upper compartment 26 is greater than or equal to the extension
of the coils 36 around the lower compartment 28.
[0028] According to one embodiment of the freezer 10, the coils are
distributed in the side walls 14 and 16 and in the rear wall 22 so
as to have an almost constant average density along the section
which bounds the upper compartment 26 and so as to have a variable
density along the section which bounds the lower compartment 28. In
particular, the density increase preferably from the bottom towards
the top of the lower compartment 28.
[0029] According to some embodiments of the freezer 10, more than
half of the coils 36 extend around the upper compartment 26.
According to the embodiment of the freezer 10 shown in FIG. 4, 54%
of the total of the coils extend around the upper compartment 26
and the remaining 46% extend around the lower compartment 28.
[0030] With such a distribution of the coil density, it is possible
to exploit in an optimum manner the natural convention which tends,
as a result of gravity, to displace the cold air downwards.
[0031] As mentioned above, the shelf 24 defines an air-tight
closure between the upper compartment 26 and the lower compartment
28. This seal may be achieved, for example, by means of a silicone
bead and prevents any mutual contamination of the samples stored in
the two compartments. In this respect, the fact that the shelf 24
is thermally conducting, makes it easier to achieve a uniform
temperature inside the two compartments even when there is no
circulating air flow. As already mentioned, according to some
embodiments of the freezer 10, the overall internal volume is
divided up differently between the upper compartment 26 and the
lower compartment 28, preferably so that the lower compartment 28
has a volume greater than that of the upper compartment 26. For
example, in the embodiment of the accompanying figures, the volume
of the upper compartment 26 constitutes 45% of the total cooled
volume, while the remaining 55% is destined for the lower
compartment 28. Applying this proportion, a freezer 10 according to
the invention with an overall cooled volume of 800 litres has
preferably an upper compartment 26 with a volume of 360 litres and
a lower compartment 28 with a volume of 440 litres.
[0032] In the front view of the freezer 10, the two thermally
insulating doors 30 and 32 are separated by a band 38 which is also
thermally insulating.
[0033] According to one embodiment, the upper door 30 and the lower
door 32 of the freezer 10 are identical to each other. Considering
that the doors 30 and 32 are identical to each other, the
difference in the volumes of the respective compartments 26 and 28
is due to the fact that the shelf 24 has a thickness smaller than
that of the band 38 and the fact that the shelf 24 is mounted
above, flush with the band 38. For this reason, the lower
compartment 28 is internally higher than the upper compartment
26.
[0034] Moreover, mounting of the shelf 24 above, flush with the
band 38, facilitates substantially the operations for internal
cleaning of the upper compartment 26. This particular configuration
of the freezer 10 is clearly visible from a comparison of FIG. 1
with FIG. 2. In FIG. 1, in fact, the view from above shows how the
surface 24 is mounted flush with the band 38, while in FIG. 2 the
view from below shows the difference in thickness between the shelf
24 and the band 38. This type of distribution of the volumes acts
in synergy with the particular distribution of the coil density,
allowing the natural convection to be exploited even more
effectively.
[0035] With the particular configuration described above, where the
density of the coils 36 is variable along the height of the cabinet
12 and, preferably, where the volumes of the two compartments 26
and 28 are different, it is possible to obtain, during operation, a
temperature which is substantially the same in both compartments 26
and 28. Specific tests carried out by the applicant have shown how
the temperatures in the two compartments 26 and 28 differ at the
most by .+-.1.degree. C. This difference is the same as or less
than the differences which commonly occur between the two
compartments of conventional freezers with air circulation.
[0036] According to one embodiment, the freezer 10 also comprises
control means for allowing separate access to the two compartments
26 and 28. For example, each of the two doors 30 and 32 may be
protected by an independent control system based on identification
of the user by means of an electronic key. A control system of this
type is already used by the applicant on other devices with the
trade name Bioguard.RTM.. By means of this system, the users may be
provided with a programmable electronic key (for example a card)
which allows access to only one compartment or to both
compartments.
[0037] In the light of the above description it will be clear to
the person skilled in the art how the freezer according to the
invention is able to overcome the drawbacks mentioned above with
reference to the prior art.
[0038] In particular, in the light of all that described above, it
will be clear how with the freezer 10 according to the invention it
is possible to obtain a temperature which is substantially the same
inside the two compartments 26 and 28, without at the same time the
risk of mutual contamination and without the need for duplication
of the refrigeration plant.
[0039] With regard to the abovementioned embodiments of the
double-door freezer, the person skilled in the art may, in order to
satisfy specific requirements, make modifications to and/or replace
elements described with equivalent elements, without thereby
departing from the scope of the accompanying claims.
* * * * *