U.S. patent application number 11/007902 was filed with the patent office on 2005-07-14 for evaporator device with improved heat transfer and method.
This patent application is currently assigned to Scotsman Ice Systems. Invention is credited to Allison, Matthew, Andresen, Michael, Baker, Melvin, Sowa, Cassimer S..
Application Number | 20050150250 11/007902 |
Document ID | / |
Family ID | 34676830 |
Filed Date | 2005-07-14 |
United States Patent
Application |
20050150250 |
Kind Code |
A1 |
Allison, Matthew ; et
al. |
July 14, 2005 |
Evaporator device with improved heat transfer and method
Abstract
An evaporator device and method of making the device. The
evaporator device comprises a one-piece metallic body, which is
preferably aluminum or an alloy thereof, with a refrigerant tube
embedded therein. The metallic body further includes horizontal
fins and vertical partitions protruding from at least one surface
that define an array of ice forming cells. The one-piece metallic
body is formed by a die casting process that eliminates the
conventional assembly steps of separate evaporator pans,
refrigerant tube pieces, vertical partitions horizontal fins and
other parts.
Inventors: |
Allison, Matthew;
(Mundelein, IL) ; Baker, Melvin; (Grayslake,
IL) ; Sowa, Cassimer S.; (Racine, WI) ;
Andresen, Michael; (Lake Villa, IL) |
Correspondence
Address: |
Paul D. Greeley, Esq.
Ohlandt, Greeley, Ruggiero & Perle, L.L.P.
10th Floor
One Landmark Square
Stamford
CT
06901-2682
US
|
Assignee: |
Scotsman Ice Systems
|
Family ID: |
34676830 |
Appl. No.: |
11/007902 |
Filed: |
December 9, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60528227 |
Dec 9, 2003 |
|
|
|
Current U.S.
Class: |
62/515 ;
62/340 |
Current CPC
Class: |
F25B 39/02 20130101;
F25C 1/12 20130101 |
Class at
Publication: |
062/515 ;
062/340 |
International
Class: |
F25C 005/08; F25C
001/00; F25B 039/02 |
Claims
What is claimed is:
1. An evaporator device for an ice machine comprising a metallic
body that has a winding pattern of a metallic refrigerant tube
embedded therein and that is shaped to have a plurality of parallel
fins protruding from a surface thereof.
2. The evaporator device of claim 1, wherein said body is a metal
that is selected from the group consisting of: aluminum and
aluminum alloy.
3. The evaporator device of claim 1, wherein said winding pattern
is entirely embedded in said body, and wherein said winding pattern
is a serpentine pattern that includes a plurality of runs that are
at least partially in registration with spaces between said
fins.
4. The evaporator device of claim 1, wherein said refrigerant tube
has first and second ends located outside said body.
5. The evaporator device of claim 1, wherein said fins are inclined
downwardly at a slight angle for gravity assistance of ice
removal.
6. The evaporator device of claim 1, wherein said refrigerant tube
is a metal that is selected from the group consisting of: copper,
and stainless steel.
7. The evaporator device of claim 1, wherein said metallic body
comprises a plurality of vertical partitions protruding from said
surface, wherein said vertical partitions, said fins and said
surface define an array of ice forming cells.
8. The evaporator device of claim 7, wherein said winding
arrangement is at least partially in registration with one or more
of said ice forming cells.
9. The evaporator device of claim 1, wherein said surface is a
first surface, wherein said plurality of fins is a first plurality
of fins, and wherein said body is shaped to have a second surface
with a second plurality of parallel fins protruding therefrom.
10. The evaporator device of claim 9, wherein said winding pattern
comprises a plurality of runs that are at least partially in
registration with spaces between each of said pluralities of
fins.
11. The evaporator device of claim 9, wherein said metallic body
further comprises a first plurality of vertical partitions
protruding from said first surface and a second plurality of
vertical partitions protruding from said second surface, wherein
said first vertical partitions, said first fins and said first
surface define a first array of ice forming cells, and wherein said
second partitions, said second fins and said second surface define
a second array of ice forming cells.
12. A method of making an evaporator device for an ice machine
comprising: disposing a metallic refrigerant tube having a winding
pattern in a casting die; and casting molten metal in said die so
that said molten metal forms a body that embeds said winding
pattern, wherein said die is shaped to form a plurality of fins
that protrude from a surface of said body.
13. The method of claim 12, wherein said metal is selected from the
group consisting of: aluminum and aluminum alloy.
14. The method of claim 12, wherein said winding pattern is a
serpentine pattern that includes a plurality of runs that are at
least partially in registration with spaces between said fins.
15. The method of claim 12, wherein said refrigerant tube has first
and second ends located outside said body.
16. The method of claim 12, wherein said fins are inclined
downwardly at a slight angle for gravity assistance of ice
removal.
17. The method of claim 12, wherein said refrigerant tube is a
metal that is selected from the group consisting of: copper and
stainless steel.
18. The method of claim 12, further comprising a plurality of
vertical partitions protruding from said surface, wherein said
vertical partitions, said fins and said surface define an array of
ice forming cells.
19. The method of claim 18, wherein said winding arrangement is at
least partially in registration with one or more of said ice
forming cells.
20. The method of claim 12, wherein said surface is a first
surface, wherein said plurality of fins is a first plurality of
fins, and wherein said body is shaped to have a second surface with
a second plurality of parallel fins protruding therefrom.
21. The method of claim 20, wherein said winding pattern comprises
a plurality of runs that are at least partially in registration
with spaces between each of said pluralities of fins.
22. The method of claim 20, further comprising a first plurality of
vertical partitions protruding from said first surface and a second
plurality of vertical partitions protruding from said second
surface, wherein said first vertical partitions, said first fins
and said first surface define a first array of ice forming cells,
and wherein said second partitions, said second fins and said
second surface define a second array of ice forming cells.
Description
RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Patent Application Ser. No. 60/528,227, filed on Dec. 9, 2003, the
entire contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to an evaporator device for an ice
machine that has a small number of parts and an improved thermal
transfer between a circulating refrigerant and an ice-forming
surface. This invention also relates to a method for making the
evaporator device.
BACKGROUND OF THE INVENTION
[0003] Evaporator devices generally include an array of ice cells
arranged in a pattern and a refrigerant tube that is positioned
adjacent the pattern to provide cooling during ice making and
heating during defrost and harvest. For example, the pattern may be
a plurality of parallel rows or a grid of horizontal rows and
vertical columns.
[0004] It is known to construct an ice cell array with thermally
conductive metal, such as copper or aluminum. An example of a
copper evaporator device is shown in U.S. Pat. No. 4,459,824. The
evaporator device, when constructed of copper, is plated with a
suitable metal, such as tin or nickel. The plating is required by
National Sanitation Foundation codes, which prohibit the use of
copper parts in contact with food products. The plating process
results in waste products that need to be handled with
environmentally acceptable procedures. In addition, plating
degradation can occur at solder fillets used in the construction of
the array of cells or their connection to other parts over which
the water used in the ice making process may flow. This can result
in a formation of copper oxides that could contaminate the ice.
[0005] Examples of evaporator devices that use aluminum parts to
construct the ice cell array are shown in U.S. Pat. Nos. 3,430,452,
5,129,237 and 5,193,357. For instance, U.S. Pat. No. 5,193,357
discloses a plurality of horizontal integral aluminum pieces
arranged side by side to form a grid of ice cells. However, the
back of each ice cell contains a gap that is filled entirely or
partially with brazing material. Brazing material or soldering
material can deteriorate over time, thereby resulting in
unreliability. Moreover, the evaporator device construction is
limited to one-sided ice cell arrays.
[0006] U.S. Pat. No. 6,247,318 discloses an evaporator device
comprising a plurality of vertical partitions that are assembled
side by side having bore holes through which runs of copper tubing
are threaded and then mechanically expanded. External tube bends
are then connected as by soldering to the runs to form a contiguous
winding. This evaporator device comprises a multiplicity of parts
that must be assembled as well as tube bends that are outside the
evaporator body formed by the vertical partitions.
[0007] U.S. Pat. No. 5,129,237 discloses an evaporator device
constructed of a base plate from which extend row wide fins. The
evaporator device is a molded body that includes a plurality of
horizontal bores that are interconnected by a plurality of tube
bends that are external to the molded body. This arrangement has
the disadvantage of requiring assembly of the tube bends to the
bores of the body as well as a multiplicity of parts.
[0008] Thus, there is a need for an evaporator device that is not
formed with brazing material or soldering material.
[0009] There is also a need for an evaporator device that has a
small number of parts.
SUMMARY OF THE INVENTION
[0010] An evaporator device of the present invention comprises a
metallic body that has a winding pattern of a metallic refrigerant
tube embedded therein and that is shaped to have a plurality of
parallel fins protruding from a surface thereof. The metallic body
is preferably a metal that is selected from the group consisting
of: aluminum and aluminum alloy.
[0011] In one embodiment of the evaporator device of the present
invention, the winding pattern is entirely embedded in the body.
The winding pattern is preferably a serpentine pattern that
includes a plurality of runs that are at least partially in
registration with spaces between the fins. The refrigerant tube has
first and second ends that are located outside the body. The
refrigerant tube is preferably a metal that is selected from the
group consisting of: copper and stainless steel.
[0012] The fins are preferably inclined downwardly at a slight
angle for gravity assistance of ice removal.
[0013] In another embodiment of the evaporator device of the
present invention, the metallic body comprises a plurality of
vertical partitions protruding from the surface. The vertical
partitions, the fins and the surface define an array of ice forming
cells. The winding arrangement is at least partially in
registration with one or more of the ice forming cells.
[0014] In another embodiment of the evaporator device of the
present invention, the metallic body has a first surface with a
first plurality of fins protruding therefrom and a second surface
with a second plurality of parallel fins protruding therefrom. The
winding pattern comprises a plurality of runs that are at least
partially in registration with spaces between each of the
pluralities of fins.
[0015] In another embodiment of the evaporator device of the
present invention, the metallic body further comprises a first
plurality of vertical partitions protruding from the first surface
and a second plurality of vertical partitions protruding from the
second surface. The first vertical partitions, the first fins and
the first surface define a first array of ice forming cells. The
second partitions, the second fins and the second surface define a
second array of ice forming cells.
[0016] A method of the present invention makes an evaporator device
for an ice machine by disposing a metallic refrigerant tube having
a winding pattern in a casting die and casting molten metal in the
die so that the molten metal forms a body that embeds the winding
pattern. The die is shaped to form a plurality of fins that
protrude from a surface of the body. The metal is preferably
selected from the group consisting of: aluminum and aluminum alloy.
The refrigerant tube is preferably a metal that is selected from
the group consisting of: copper and stainless steel.
[0017] The winding pattern is a preferably a serpentine pattern
that includes a plurality of runs that are at least partially in
registration with spaces between the fins.
[0018] In another embodiment of the method of the present
invention, the refrigerant tube has first and second ends located
outside the body.
[0019] In another embodiment of the method of the present
invention, the fins are inclined downwardly at a slight angle for
gravity assistance of ice removal.
[0020] In another embodiment of the method of the present
invention, a plurality of vertical partitions protrude from the
surface. The vertical partitions, the fins and the surface define
an array of ice forming cells. The winding arrangement is at least
partially in registration with one or more of the ice forming
cells.
[0021] In another embodiment of the method of the present
invention, the metallic body has a first surface having a first
plurality of parallel fins protruding therefrom and a second
surface with a second plurality of parallel fins protruding
therefrom. The winding pattern comprises a plurality of runs that
are at least partially in registration with spaces between each of
the pluralities of fins.
[0022] In another embodiment of the method of the present
invention, a first plurality of vertical partitions protrudes from
the first surface and a second plurality of vertical partitions
protrudes from the second surface. The first vertical partitions,
the first fins and the first surface define a first array of ice
forming cells. The second partitions, the second fins and the
second surface define a second array of ice forming cells.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Other and further objects, advantages and features of the
present invention will be understood by reference to the following
specification in conjunction with the accompanying drawings, in
which like reference characters denote like elements of structure
and:
[0024] FIG. 1 is a plan view of an evaporator device of the present
invention;
[0025] FIG. 2 is a side view of the evaporator device of FIG.
1;
[0026] FIG. 3 is a cross-sectional view of FIG. 1 taken along line
3; and
[0027] FIG. 4 is a view of detail 4 of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0028] Referring to FIGS. 1-4, an evaporator device of the present
invention includes a one-piece or integral body 22 that is a
one-piece integral metallic structure in which a refrigerant tube
36 is embedded. Refrigerant tube 36 has tube ends 38 and 40, which
extend outside body 22.
[0029] Body 22 has a first surface 44 and a second surface 46 that
are preferably substantially parallel and opposite one another.
Body 22 also includes a plurality of fins 54 that protrude
outwardly from first surface 44. Fins 54 extend horizontally along
first surface 44, are spaced from one another and are substantially
parallel. Body 22 further includes a plurality of fins 56 that
protrude outwardly from second surface 46. Fins 56 extend
horizontally along first surface 46, are spaced from one another
and are substantially parallel. Fins 54 and 56 are located
substantially opposite one another.
[0030] Body 22 further includes a plurality of vertical partitions
28 disposed along first surface 44. Vertical partitions 28 are
spaced apart and parallel to one another. Vertical partitions 28
together with horizontal fins 54 form an array of ice forming cells
in rows and columns. Evaporator device 20 further includes a
plurality of vertical partitions 32 disposed along second surface
46. Vertical partitions 32 are spaced apart and parallel to one
another. Vertical partitions 32 together with horizontal fins 56
form an array of ice forming cells in rows and columns.
[0031] Body 22 further includes vertical sides 24 and 26 that are
substantially parallel to vertical partitions 28 and 32.
[0032] The ice forming cells on first surface 44 are in substantial
registration with the ice forming cells on second surface 46.
Refrigerant tube 36 has a serpentine winding arrangement that has
runs 50 along horizontal rows of the ice forming cells. Bends 42
are arranged with runs 50 to form the serpentine pattern.
[0033] Each ice forming cell is substantially identical. By way of
example, an ice forming cell 30, which is depicted in FIGS. 1, 3
and 4, will be described in detail. Fins 54A and 54B and first
surface 44 of body 22 and vertical partitions 28A and 28B define
ice forming cell 30. Ice forming cell 30 has a mirror image ice
forming cell 34 substantially opposite on second surface 46. The
top most run 50 of refrigerant tube 36 is at least partially in
registration with ice forming cells 30 and 34. Since refrigerant
tube 36 is embedded in body 22, thermal transfer from refrigerant
flow in refrigerant tube 36 to ice forming cells 30 and 34 is very
efficient.
[0034] Referring to FIGS. 3 and 4, the cross-sections of fins 54
and 56 are generally tapered from first and second surfaces to
their tips. For example, a surface 60 of fin 54B has a slight angle
of about 30.degree. so as to release an ice cube during a harvest
cycle. A surface 62 of fin 54B has a slight angle of about
15.degree. to assure that water penetrates to rear of ice forming
cell 30.
[0035] In addition, the sides of the cube cells, namely vertical
partitions 28 and 32, are tapered outwardly from first and second
surfaces 44 and 46. Preferably, the angle of taper is about
5.degree.. This is done both to facilitate the casting process and
to let air in behind the slab of ice as it begins to slide off body
22. The angle of taper can be any angle greater than about
1.degree.. As the angle of taper is increased, the material
required for the casting increases. The smaller the angle of taper,
the less impact it has on harvest because it lets less air in
behind the ice.
[0036] Body 22 is made by positioning the serpentine winding
arrangement of refrigerant tube 36 in a casting die and then
casting molten metal in the die so that the molten metal encases or
embeds refrigerant tube 36. The shape of the die allows refrigerant
tube ends 38 and 40 to be located outside the molten metal. The
shape of the die also allows vertical partitions 28 and 32 as well
as sides 24 and 26 to be formed by the casting process step. Thus,
body 22 is formed as a one-piece integral structure in which the
winding arrangement of refrigerant tube 36 is embedded or
encased.
[0037] The body 22 is preferably aluminum or aluminum alloy and
refrigerant tube 36 is preferably copper or stainless steel.
[0038] All surfaces of evaporator device 20 are coated with a
coating that prevents corrosion. The coating, for example, may be
nickel or tin plating.
[0039] The evaporator device of the present invention has the
following advantages:
[0040] 1. Enhanced heat transfer. Rather than heat passing through
only a part of the surface of the refrigerant tube in contact with
the pan holding the ice forming fins, the aluminum encases the
refrigerant tube, thereby allowing heat transfer through the full
perimeter of the refrigerant tube.
[0041] 2. Enhanced heat transfer by virtue of two ice making
surfaces using only one copper refrigerant tube.
[0042] 3. Reduced part count. There is only a one-piece structure
of metallic body 22 with embedded refrigerant tube 36 vis-a-vis a
traditional design that has a refrigerant tube, a pan and a
plurality of strips.
[0043] 4. No reliance on sensitive bonding processes, such as
soldering. Thus no chance of the evaporator assembly coming
apart.
[0044] 5. Lighter weight. (Aluminum vs. copper).
[0045] 6. Easier to manufacture.
[0046] Although evaporator device 20 is shown with ice forming
cells on both sides of body 22, it is contemplated that body 22 may
have ice forming cells on only one side. In this case, the fins of
one side could be omitted or simply not used. Also, the vertical
partitions can be omitted for the case that ice cubes are not
required. In such case the ice would be formed along the length of
the space between adjacent fins.
[0047] The present invention having been thus described with
particular reference to the preferred forms thereof, it will be
obvious that various changes and modifications may be made therein
without departing from the spirit and scope of the present
invention as defined in the appended claims.
* * * * *