U.S. patent application number 13/735861 was filed with the patent office on 2013-10-03 for thermal receptacle with phase change material containing insert.
The applicant listed for this patent is Entropy Solutions, Inc.. Invention is credited to Luke HAUN, Eric Robert LINDQUIST, William Rusty SUTTERLIN, Preston Noel WILLIAMS.
Application Number | 20130255824 13/735861 |
Document ID | / |
Family ID | 49233276 |
Filed Date | 2013-10-03 |
United States Patent
Application |
20130255824 |
Kind Code |
A1 |
WILLIAMS; Preston Noel ; et
al. |
October 3, 2013 |
THERMAL RECEPTACLE WITH PHASE CHANGE MATERIAL CONTAINING INSERT
Abstract
A thermal receptacle having a side wall which has an inner
surface and a spaced outer surface. An interstitial chamber may be
defined by the space between the inner and outer surfaces. A phase
change material containing insert is provided into the receptacle.
The insert contains a phase change material or a plurality of
different phase change materials. Phase change material may also be
located within the interstitial chamber. The phase change material
regeneratively absorbs thermal energy from a hot liquid in the
receptacle thereby rapidly lowering the temperature of the liquid
and then the material releases the thermal energy back to the
liquid to maintain the temperature of the liquid.
Inventors: |
WILLIAMS; Preston Noel;
(Richfield, MN) ; LINDQUIST; Eric Robert; (Medina,
MN) ; SUTTERLIN; William Rusty; (Tuscaloosa, AL)
; HAUN; Luke; (Minneapolis, MN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Entropy Solutions, Inc. |
Plymouth |
MN |
US |
|
|
Family ID: |
49233276 |
Appl. No.: |
13/735861 |
Filed: |
January 7, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61583888 |
Jan 6, 2012 |
|
|
|
Current U.S.
Class: |
141/1 ;
220/592.16 |
Current CPC
Class: |
F25D 3/08 20130101; F25D
2331/803 20130101; F25D 31/007 20130101; F25D 2303/0842 20130101;
B65D 81/18 20130101 |
Class at
Publication: |
141/1 ;
220/592.16 |
International
Class: |
B65D 81/18 20060101
B65D081/18 |
Claims
1. A liquid receptacle comprising: a vessel having an open upper
end and closed lower end and a wall connecting said upper end and
said lower end; and a phase change material disposed within an
insert, said insert adapted to be placed within said vessel for
regeneratively absorbing thermal energy from the liquid and then
releasing the thermal energy to the liquid to maintain the
temperature of the liquid within a desired temperature range.
2. The liquid receptacle of claim 1 wherein the insert is secured
to a sealing cover.
3. The liquid receptacle of claim 2 wherein the insert is a closed
tube.
4. The liquid receptacle of claim 3 wherein the closed tube is a
convoluted metal tube.
5. The liquid receptacle of claim 4 wherein ends of the closed tube
are secured to the sealing cover.
6. The liquid receptacle of claim 3 wherein the insert is a coiled
tube.
7. The liquid receptacle of claim 1 wherein the vessel has an
insulated outer shell defining an interstitial chamber.
8. The liquid receptacle of claim 7 wherein a second phase change
material is placed into the interstitial chamber of the insulated
outer shell.
9. A liquid receptacle comprising: a vessel for containing a
liquid, said vessel having an open upper end and closed lower end
and a wall connecting said upper end and said lower end; a sealing
cover adapted to engage the open upper end of the vessel and
prevent loss of liquid; and an insert adapted to be placed within
said vessel, said insert being in contact with the liquid and
containing a phase change material which regeneratively absorbs
thermal energy from the liquid and then releases the thermal energy
to the liquid to maintain the temperature of the liquid within a
desired temperature range.
10. The liquid receptacle of claim 9 wherein the insert is secured
to the sealing cover.
11. The liquid receptacle of claim 10 wherein the insert is a
closed tube.
12. The liquid receptacle of claim 11 wherein the closed tube is a
convoluted metal tube.
13. The liquid receptacle of claim 12 wherein ends of the closed
tube are secured to the sealing cover.
14. The liquid receptacle of claim 9 wherein the insert is a coiled
tube.
15. The liquid receptacle of claim 9 wherein the vessel has an
insulated outer shell defining an interstitial chamber.
16. The liquid receptacle of claim 15 wherein a second phase change
material is placed into the interstitial chamber of the insulated
outer shell.
17. A method of regeneratively absorbing thermal energy from a
liquid and then releasing the thermal energy to the liquid to
maintain temperatures of the liquid within a desired temperature
range, said method comprising: dispensing a liquid into a vessel;
and sealing the vessel with a cover, said cover including a hollow
insert containing a phase change material, with said insert being
placed in fluid contact with the liquid when the vessel is sealed
with the cover.
18. The method of claim 17 further comprising thermally
pre-treating the insert and phase change material prior to sealing
the vessel with the cover.
19. The method of claim 18 wherein the liquid is a hot liquid and
the phase change material contained within the insert is heated
prior to sealing the vessel with the cover.
20. The method of claim 19 further comprising thermally
pre-treating the vessel prior to said dispensing the liquid into
the vessel.
Description
RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application Ser. No. 61/583,888, filed Jan. 6, 2012, and
incorporated herein by reference.
TECHNICAL FIELD
[0002] The subject invention relates generally to liquid
receptacles or containers and more specifically to a receptacle
having a phase change material insert and which rapidly cools a hot
liquid (or heats a cold liquid) to a desired range and then
maintains the fluid in the desired range for an extended
period.
BACKGROUND OF THE INVENTION
[0003] There have been many attempts in the past to maintain
liquids and solids within certain temperature ranges. Hot beverages
are usually prepared and served at temperatures well above the
desired temperature range of consumption. Typically, the consumer
must wait some time before the beverage to sufficiently cool before
drinking it. Some impatient consumers will attempt to drink the
beverage too soon resulting in burns to the mouth. Similarly, if
the drink is spilled before it has had sufficient time to cool,
burns to the skin may result. Therefore, it is desirable to rapidly
cool the beverage from the temperature at which it is served to an
acceptable temperature range for consumption. Once the beverage is
within the acceptable drinking temperature range, it is desirable
to maintain the temperature of the beverage within this range for
as long as possible.
[0004] Many approaches have been tried for both rapidly cooling a
hot beverage and for maintaining the temperature of the beverage
within an acceptable drinking temperature range. To rapidly cool a
hot beverage, ice or a cool liquid (e.g., water or milk) can be
added to the hot beverage. This approach rapidly cools the beverage
but dilutes the hot beverage. This is frequently undesirable. This
approach is often inconvenient and imprecise; if the person adds
too little or too much, the temperature of the hot beverage will be
higher or lower than desired and may require further attention.
Finally, this approach does not provide any assistance in
maintaining the temperature of the hot beverage in the acceptable
drinking temperature range. Once the beverage reaches an acceptable
temperature, it will continue to lose thermal energy to its
surroundings. This results in the beverage becoming cool too
quickly. Therefore, the beverage remains within an acceptable
drinking temperature range for only a short period.
[0005] A hot beverage can also be cooled by pouring it into a cool
container. Thermal energy is transferred from the hot beverage to
the cool container thereby warming the container and cooling the
beverage. This approach suffers from some of the same limitations
as adding cool liquid or ice. If the cup is too cool or too warm or
has too much or too little thermal mass, the beverage will
stabilize at the wrong temperature. Also, while a heavy container
will slow the rate of cooling somewhat due to the increase in the
total thermal mass of the system, the effect will be small and the
beverage will only remain in the ideal drinking range for a short
period.
[0006] One primary method employed for slowing the cooling rate of
a beverage has been to insulate the container. Everything from
simple foam cups to expensive and sophisticated vacuum insulated
mugs have been used. These approaches slow the cooling rate of the
beverage. However, the ability of the insulated mugs currently on
the market to maintain beverage temperatures is relatively limited.
Stainless, vacuum insulated mugs are excellent at maintaining
temperature, but no product currently exists which can passively
cool a hot beverage quickly. Also, the beverage in an insulated
container will continue to cool despite the insulation. The cooling
rate will only be slowed. Insulation does not provide a way to add
thermal energy back to the beverage.
SUMMARY OF THE INVENTION
[0007] This invention addresses the need to rapidly lower the
temperature of a hot liquid to a desired warm range suitable for
human contact and then maintain the liquid in the desired warm
range for an extended period of time. The invention includes a
liquid receptacle having a side wall with a lower end and an open
upper end. A bottom wall closes off the lower end of the side wall.
The side wall has an inner surface and a spaced outer surface. An
interstitial chamber may be defined by the space between the inner
and outer surfaces. An insulation layer can be disposed at least
partially between the chamber and the outer surface of the
receptacle. A phase change material containing insert is provided
into the receptacle. The insert may be fixed in place or may be
removable to facilitate cleaning of the receptacle. The insert
contains a phase change material or a plurality of different phase
change materials. Phase change material may also be located within
the interstitial chamber. The phase change material regeneratively
absorbs thermal energy from a hot liquid in the receptacle thereby
rapidly lowering the temperature of the liquid and then the
material releases the thermal energy back to the liquid to maintain
the temperature of the liquid.
[0008] The present invention is suitable for many applications
requiring the rapid lowering of the temperature of a hot liquid in
a container and then the maintenance of the temperature of the
liquid for an extended period of time. Among other things, the
invention can be applied to drinking mugs or cups, baby bottles,
carafes, etc. The present invention may also be suitable for
rapidly raising the temperature of a liquid in a container and then
the maintenance of the temperature of the liquid for an extended
period of time.
[0009] Embodiments of the present invention may find applicability
in diverse uses such as dispensing of medicines and fluids in the
life science industries. For example, an embodiment of the present
invention may include a vessel for dispensing fluids in a lab or
science setting where the fluid is dispensed within a specific
temperature range(s).
[0010] The demand for hot beverages is very high, especially for
coffee and tea, the most popular adult hot beverages. Therefore, it
is desirable to develop a reusable beverage container that will
rapidly cool coffee drinks to an acceptable drinking temperature,
will maintain the temperature within an acceptable temperature
range for an extended period, requires neither manipulation by the
consumer or the input of external energy, and is portable.
[0011] The foregoing has outlined rather broadly the features and
technical advantages of the present invention in order that the
detailed description of the invention that follows may be better
understood. Additional features and advantages of the invention
will be described hereinafter which form the subject of the claims
of the invention. It should be appreciated by those skilled in the
art that the conception and specific embodiment disclosed may be
readily utilized as a basis for modifying or designing other
structures for carrying out the same purposes of the present
invention. It should also be realized by those skilled in the art
that such equivalent constructions do not depart from the spirit
and scope of the invention as set forth in the appended claims. The
novel features which are believed to be characteristic of the
invention, both as to its organization and method of operation,
together with further objects and advantages will be better
understood from the following description when considered in
connection with the accompanying figures. It is to be expressly
understood, however, that each of the figures is provided for the
purpose of illustration and description only and is not intended as
a definition of the limits of the present invention.
DESCRIPTION OF THE DRAWINGS
[0012] In the accompanying drawings which form part of the
specification and wherein like numerals and letters refer to like
parts wherever they occur:
[0013] FIG. 1 is a perspective view of an embodiment of the present
invention.
[0014] FIG. 2 is a cross-sectional view of the vessel of FIG.
1.
[0015] FIG. 3 is a perspective illustration of the insert of FIG.
1.
[0016] FIG. 4 is a top plan view of the insert of FIG. 3 inserted
into the vessel of FIG. 2.
[0017] FIG. 5 is perspective view of another embodiment of the
invention.
[0018] FIG. 6 is a perspective view of another embodiment of the
insert of FIG. 1.
[0019] FIGS. 7 and 8 are perspective views of another embodiment of
the present invention.
[0020] FIG. 9 is a perspective view of yet another embodiment of
the present invention.
[0021] FIG. 10 is a perspective view of the insert 21 of the
receptacle of FIG. 9.
[0022] FIG. 11 is a top view of a hollow tube used to form the
insert 21 of FIG. 9.
[0023] FIGS. 12 and 13 are comparisons of thermal characteristics
of a PCM receptacle of the present invention as compared to a
control.
DETAILED DESCRIPTION OF THE INVENTION
[0024] One embodiment of the present invention is a coffee cup.
Such an embodiment can be used for coffee or any liquid that is
desired to be brought into and maintained within a desired
temperature range. The cup rapidly cools the coffee or liquid by
employing phase change materials (PCMs) to help manage the
temperature of the coffee. The phase change materials are placed
within an insert adapted to be inserted into the cup. Additional
phase change materials can be placed inside the cup walls, such as
disclosed in U.S. Pat. No. 6,634,417, incorporated herein by
reference.
[0025] Cup embodiments of the present invention include phase
change material in an insert or inserts designed to be placed
within the interior of the liquid cavity of the cup. The insert can
be of several different designs but each design increases the
amount of surface area that is between the coffee and the PCM (as
compared to PCM in the walls of the cup alone) thereby increasing
the thermal transfer between the hot coffee and the PCM cooling the
coffee quicker than a non-enhanced cup or the cup of the previous
invention. The more surface area between the hot drink and the PCM
the quicker the hot drink will cool.
[0026] In one version of the present invention the insert is
designed to have hollow fins that extend outwardly from the
vertical centerline of the hot drink cup toward the sides of the
cup. The hollow portion of the fins are filled with a phase change
material or materials with solid/liquid transition temperatures
selected to optimize the desired thermal performance of the cup
(different people may have cooler or warmer desired coffee drinking
temperature ranges). The fins may or may not be attached to the
walls of the cup. The finned insert may be a part of the cup itself
or be removable from the cup as a separate unit or units. There may
be space below the fins to allow coffee to move between the three
cavities that are formed by the fins. This may be used in such a
manner as to have the first amount of hot drink to be consumed
drawn from the bottom of the hot drink cup where the cooler drink
will gravitate. This insert may or may not be attached to a
removable lid of the hot drink cup.
[0027] Another version of the present invention is to place PCM
inside of tubing that is formed in a single, double or multiple
spiral fashion. The tubing may be attached to a removable lid of
the coffee cup.
[0028] Embodiments of the present invention may include two or more
different PCM's. For example, a single insert may include two or
more separate cavities containing two or more different PCM's.
[0029] The solid/liquid transition temperature of the PCM is
selected to optimize the thermal management performance
characteristics of the coffee or other hot drink. Coffee may be
introduced into the cup at a temperature that is higher than the
desired consumption temperature range. The PCM will liquefy while
absorbing heat from the coffee until the coffee is within the
desired consumption temperature range or all the PCM has been
liquefied. When the temperature of the coffee is below the
solid/liquid transition temperature of the PCM the PCM will release
heat back into the coffee maintaining the temperature of the coffee
within the desired drinking temperature range for a longer period
of time that the non-enhanced coffee cup.
[0030] The inserts can be engineered to be buoyant or partially
buoyant. That means that PCM containing fins or units can be
engineered to always "float" towards the top of the coffee in the
cup and not above the top of the coffee. This would allow the PCM
to absorb heat from the hottest coffee (which will gravitate to the
top of the cup) and allow the PCM to release its stored heat back
into the coffee itself and not in the airspace above the
coffee.
[0031] Another application for the invention would be a beer mug. A
liquid PCM can quickly warm the beer to its optimal drinking
temperature range and keep the beer within the optimal drinking
temperature range for a longer period of time that a non-enhanced
beer mug.
[0032] Another embodiment of the present invention includes a
device for dispensing medicines and fluids in the life science
industry. For example, an embodiment of the present invention may
include a vessel for dispensing fluids in a lab or science setting
where the fluid is dispensed within a specific temperature
range(s).
[0033] Referring to the Figures, wherein like numerals indicate
like or corresponding parts throughout the several views, a liquid
receptacle is generally indicated at 10 in FIG. 1. The receptacle
10 includes a vessel 12 and an insert 21. Vessel 12 includes an
open upper end 13 and a closed lower end 14 and an inner wall 16
connecting the upper 13 and lower 14 ends. An insulated outer shell
18 is spaced from the inner wall 16 defining an interstitial
chamber 20 therebetween. In some embodiments of the invention, a
phase change material 19 is disposed within the chamber 20, as
depicted in FIG. 2. The performance of the receptacle is greatly
enhanced by the insulated outer shell 18. The insulation slows the
loss of thermal energy from the phase change material thereby
greatly extending the period that the beverage can be maintained
within the warm range. The insulation may be provided by a vacuum
insulation system.
[0034] Insert 21 defines a hollow chamber which contains phase
change material. Insert 21 may be metal, plastic or another
suitable material with one or more hollow cavities. In other
embodiments of the invention, insert 21 is constructed of a PCM
impregnated material which contains PCM without a large visible
hollow cavity. For example, a sponge-type or paper material may be
impregnated with PCM and then provided into a container (soft,
hard, flexible, etc.) to define the insert 21.
[0035] Preferably, the inner vessel 12 and insert 21 are formed of
a material having a high thermal conductivity such as aluminum,
copper or alloys thereof. A material with a lower thermal
conductivity may also be used but the performance of the invention
will be reduced accordingly. The inner vessel 12 or insert 21 may
be coated, anodized, or plated in order to improve the appearance,
resistance to oxidation, or cleanability of the vessel 12 or insert
21. Alternatively, the vessel 12 or insert may be formed from two
or more different materials.
[0036] FIG. 3 depicts insert 21 as having multiple fins 23. FIG. 4
depicts the insert 21 of FIG. 3 inserted into vessel 12.
[0037] FIG. 5 depicts another embodiment of insert 21 inserted into
vessel 12. FIG. 6 depicts a generally S-shaped insert 21.
[0038] FIGS. 7 and 8 depict another embodiment of the invention
wherein the insert 21 is a coiled, close-ended tube containing the
PCM. Insert 21 is sized to be received into vessel 12 as shown in
FIG. 8.
[0039] FIGS. 9-11 depict yet another embodiment of the present
invention wherein the insert 21 is defined by a convoluted metal
tube 30. Tube 30 is secured to cover 32. A phase change material is
contained within the hollow tube 30. The tube ends are sealed to
contain the PCM within the tube 30. FIG. 11 shows the tube 30 prior
to being bent into the shape of FIGS. 9 and 10. Tube 30 has a
length of approximately 10 inches and a wall thickness of
approximately 0.020 inches. Tube 30 has a diameter of approximately
0.5 inches. Other embodiments of tube 30 could have different
dimensions. In one example, the tube 30 volume is approximately 2
ounces and the vessel contains approximately 16 ounces. Tube 30 may
be anodized or coated.
[0040] Convoluted metal tube 30 has a significantly increased
surface area as compared to a standard tube. It is desirable to
maximize the surface area of the insert 21 as the thermal energy
exchange rate between the hot liquid and the phase change material
is dependent on the surface area of the PCM container. The
convoluted metal tube 30 provides an energy efficient, rigid metal
structure for containing the PCM. In other examples (not shown),
the inner walls of the vessel 12 may also include convolutions if a
second PCM is contained within the interior of the vessel 12.
[0041] In the embodiment of FIGS. 9-11, tube 30 is secured to cover
32. Cover 32 thus acts to align and hold the insert 21 within the
liquid. A sealing structure 34 is provided upon cover 32 to prevent
the liquid from escaping the vessel 12 when the cover 32 is
secured. Sealing structure 34 may be a flexible sealing ring.
[0042] To use the receptacle 10, a consumer removes the lid and
pours a hot beverage or liquid into the inner vessel 12 of the
receptacle 10, which is initially at room temperature. The
thermally conductive material of the insert 21 conducts thermal
energy of the hot beverage or liquid into the phase change
material. As the phase change material absorbs the thermal energy,
the temperature of the phase change material rises from room
temperature to its phase change temperature. Preferably, the phase
change will be from solid to liquid. Many other phase change
materials are also available with acceptable phase change
temperatures. One class of phase change materials includes a set of
naturally occurring fatty acids with melting points in the range of
110.degree. F. to 160.degree. F. These materials are advantageous
due to their non-toxic and relatively innocuous characteristics. As
will be clear to one of skill in the art, many materials are
available which can be used as phase change materials. However, to
be useful for thermal management, a material must change phases at
a temperature close to the temperature range desired to be
maintained. Also, it is desirable that the material be non-toxic
and be readily available at a reasonable price.
[0043] Once the phase change material reaches its melting point,
the temperature of the phase change material will no longer rise as
the thermal energy is absorbed causing the material to melt (change
phases). As the phase change material absorbs thermal energy from
the hot beverage, the temperature of the hot beverage will fall.
The temperature of the hot beverage will continue to fall until the
beverage and the phase change material are in thermal equilibrium;
e.g., they are at the same temperature. The quantity of the phase
change material is chosen so that during its phase change it can
absorb enough thermal energy to cool the hot beverage from the
boiling point of water down to within a warm range acceptable for
human consumption. Once the hot beverage is cooled to within the
warm range, the beverage and the phase change material are at
equilibrium and the beverage is drinkable. As the beverage loses
thermal energy to the surrounding atmosphere, its temperature will
begin to fall below the phase change temperature of the phase
change material. At this point, the phase change material will
begin to transfer thermal energy back through the insert 21 into
the beverage. This thermal energy will maintain the temperature of
the hot beverage near the phase change temperature of the phase
change material as the phase change material resolidifies. Once the
phase change material converts back to the solid phase, its
temperature will begin to fall and the beverage temperature will no
longer be maintained. Because the phase change material remains at
the phase change temperature during the phase change, the beverage
will be maintained near the phase change temperature for an
extended period.
[0044] In another method of using the receptacle 10, the insert 21
is actively pre-treated prior to insertion into the liquid. For
example, the insert 21 may be heated just prior to use of
receptacle 10. An active heating element (not shown) may be used to
pre-heat the insert 21 prior to insertion into a hot liquid. For
example, insert 21 may include a resistive element which is used to
heat the insert 21. In another example insert 21 is passively
heated by an external heat source. Additional thermal benefits are
obtained by thermally pre-treating the insert 21 or vessel 12 or
both.
[0045] Referring now to FIG. 12, the thermal characteristics of the
receptacle 10 adapted for hot beverages for adults are shown. The
graph shows the temperature of a hot beverage poured into a typical
prior art plastic coffee mug (the "Control"). The temperature of
the beverage falls slowly but steadily to the upper limit of the
warm range (labeled as Drinking Temperature Range) acceptable for
human consumption, which in this example is approximately
65.degree. C. The temperature of the beverage continues to fall
until it falls below the lower limit of the warm range which in
this example is approximately 55.degree. C. Consequently, the
beverage is only within the warm range or acceptable drinking
temperature range for a short period of time.
[0046] The data labeled as "PCM Mug" illustrate the thermal
characteristics of a receptacle constructed according to the
present invention. The datapoints indicate the temperature of a hot
beverage poured into the receptacle versus time. The beverage cools
very rapidly as the thermal energy of the beverage is absorbed by
the phase change material. The beverage rapidly falls to the upper
limit of the warm range and then the cooling rate slows. The
beverage remains within the warm range for an extended period as
compared to the control.
[0047] Referring now to FIG. 13, a comparison was made between the
thermal characteristics of receptacle 10 having a PCM insert 21
versus a receptacle without the PCM insert 21 ("control"). The PCM
data depict temperature characteristics of a receptacle having PCM
insert 21. The graph depicts the temperature of a 15 ml amount of
liquid poured from the receptacle 10 and control receptacle. As
shown, the receptacle 10 with the PCM insert 21 provides the
decanted liquid within the desired temperature range (65.degree. C.
to 50.degree. C.) for a significantly longer period of time in
comparison to the control. The PCM mug maintains the liquid within
the desired temperature range for more than twice as long as the
control mug. The PCM mug maintains the temperature within the
desired range from period, t1 to t3. In comparison, the control mug
maintains the temperature within the desired range from period, t2
to t3.
[0048] Although the present invention and its advantages have been
described in detail, it should be understood that various changes,
substitutions and alterations can be made herein without departing
from the spirit and scope of the invention as defined by the
appended claims. Moreover, the scope of the present application is
not intended to be limited to the particular embodiments of the
process, machine, manufacture, composition of matter, means,
methods and steps described in the specification. As one of
ordinary skill in the art will readily appreciate from the
disclosure of the present invention, processes, machines,
manufacture, compositions of matter, means, methods, or steps,
presently existing or later to be developed that perform
substantially the same function or achieve substantially the same
result as the corresponding embodiments described herein may be
utilized according to the present invention. Accordingly, the
appended claims are intended to include within their scope such
processes, machines, manufacture, compositions of matter, means,
methods, or steps.
* * * * *