U.S. patent application number 16/313965 was filed with the patent office on 2019-07-25 for pouch filled with phase-change material and method for manufacture thereof.
This patent application is currently assigned to PROBALCO BVBA. The applicant listed for this patent is PROBALCO BVBA. Invention is credited to Karim REDJAL, Pol SPELEERS.
Application Number | 20190223636 16/313965 |
Document ID | / |
Family ID | 56550658 |
Filed Date | 2019-07-25 |
United States Patent
Application |
20190223636 |
Kind Code |
A1 |
REDJAL; Karim ; et
al. |
July 25, 2019 |
POUCH FILLED WITH PHASE-CHANGE MATERIAL AND METHOD FOR MANUFACTURE
THEREOF
Abstract
A pouch (100) filled with phase-change material, wherein the
pouch comprises a preformed first wall (110) and a second wall
(120), wherein the first wall comprises a bowl-shaped part, in
which the phase-change material is accommodated, and a peripheral
part, wherein the second wall is attached to the peripheral part of
the first wall, wherein a high vacuum prevails in the pouch, and
wherein the pouch is intended for placing against a wall to be
heated or cooled.
Inventors: |
REDJAL; Karim; (Zwevegem,
BE) ; SPELEERS; Pol; (Waregem, BE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
PROBALCO BVBA |
Kortrijk |
|
BE |
|
|
Assignee: |
PROBALCO BVBA
Kortrijk
BE
|
Family ID: |
56550658 |
Appl. No.: |
16/313965 |
Filed: |
June 29, 2017 |
PCT Filed: |
June 29, 2017 |
PCT NO: |
PCT/BE2017/000033 |
371 Date: |
December 28, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F25D 3/08 20130101; F25D
2303/08222 20130101; Y02E 60/145 20130101; Y02E 60/14 20130101;
F28D 20/02 20130101; A47G 19/027 20130101; F25D 2331/808 20130101;
F28D 2020/0008 20130101; F25D 2331/812 20130101 |
International
Class: |
A47G 19/02 20060101
A47G019/02; F28D 20/02 20060101 F28D020/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 30, 2016 |
BE |
2016/5527 |
Claims
1. A pouch filled with phase-change material, wherein the pouch
comprises a preformed first wall and a second wall, wherein the
first wall comprises a bowl-shaped part, in which the phase-change
material is accommodated, and a peripheral part, wherein the second
wall is attached to the peripheral part of the first wall, wherein
a high vacuum prevails in the pouch, and wherein the pouch is
intended for placing against a wall to be heated or cooled.
2. The pouch as claimed in claim 1, wherein the first wall and
second wall are at least 40 .mu.m thick.
3. The pouch as claimed in claim 1, wherein the first wall is a
first film and the second wall is a second film.
4. The pouch as claimed in claim 1, wherein the bowl-shaped part of
the first wall is formed by thermoforming the first film.
5. The pouch as claimed in claim 1, wherein the first wall and
second wall each comprise a welding layer and a barrier layer,
wherein the welding layer of the first wall is welded to the
welding layer of the second wall.
6. The pouch as claimed in claim 4, wherein the welding layer
comprises polypropylene and the barrier layer comprises
polyamide.
7. The pouch as claimed in claim 1, wherein the first wall and/or
the second wall comprises a layer manufactured from aluminium.
8. The pouch as claimed in claim 1, wherein the first wall and/or
the second wall are manufactured by injection moulding.
9. The pouch as claimed in claim 1, wherein the pouch is intended
for placing with the second wall against a part to be heated or
cooled, and wherein the first wall has better thermally insulating
properties than the second wall.
10. The pouch as claimed in claim 1 wherein the pouch is filled
with phase-change material not accommodated in capsules.
11. The pouch as claimed in claim 1 wherein the second wall is a
preformed wall.
12. A piece of crockery provided with a pouch as claimed in claim
1, wherein the pouch is situated in the crockery and wherein the
pouch is placed with the second wall against a wall of the crockery
to be heated or cooled.
13. A method for manufacturing a pouch filled with phase-change
material, wherein the method comprises of: shaping a first wall of
the pouch such that the first wall comprises a bowl-shaped part and
a peripheral part; placing the phase-change material in the
bowl-shaped part of the shaped first wall; attaching a second wall
of the pouch to the peripheral part of the shaped first wall such
that the phase-change material is situated between the first and
second walls, and that a high vacuum prevails in the pouch.
14. The method as claimed in claim 13, wherein the shaping of the
first wall of the pouch comprises of thermally preforming the first
wall of the pouch.
15. The method as claimed in claim 13, wherein the shaping of the
first wall comprises of injection moulding the first wall.
16. The method as claimed in claim 13, wherein attaching a second
wall to the peripheral part of the shaped first wall comprises of:
positioning the first and second wall relative to each other such
that the second wall is attachable at the peripheral part of the
first wall; drawing a vacuum in the space between the first wall
and the second wall; and sealing the pouch at the peripheral part
of the first wall.
17. The method as claimed in claim 16, wherein sealing of the pouch
at the peripheral part of the first wall comprises of welding or
glueing the second wall to the peripheral part of the first
wall.
18. The method as claimed in claim 13, wherein placing of the
phase-change material in the bowl-shaped part of the shaped first
wall comprises of melting the phase-change material, casting the
molten phase-change material in a mould and, after cooling, placing
the hardened phase-change material in the bowl-shaped part.
19. The method as claimed in claim 13, comprising of shaping the
second wall of the pouch prior to the attachment.
20. The method as claimed in claim 19, wherein the shaping of the
second wall comprises of injection moulding the second wall or
thermally preforming the second wall.
21. The method as claimed in claim 2, wherein the first wall and
second wall have a thickness of between 50 .mu.m and 150 .mu.m.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a pouch filled with
phase-change material and method for manufacturing a pouch filled
with phase-change material. The present invention further relates
to crockery provided with a pouch filled with phase-change
material.
BACKGROUND
[0002] The use of phase-change material as heat storage material,
wherein the phase-change material is able to absorb heat in a
relatively short time and to relinquish this heat again over a
longer period of time, is known. An example of such an application
is the use of phase-change material in a a plate on which hot food
is served. By making use of phase-change material the plate will
cool less quickly and the food will remain warm for longer. A
cavity filled with phase-change material is typically provided in
the plate.
[0003] Typically phase-change materials used for this and similar
applications are solid at room temperature and transpose to a
liquid phase at higher temperatures at which they absorb heat. When
the phase-change material is in the liquid phase, there is the
danger that particles of the phase-change material can escape
through the micropores of the plate. In the liquid phase the
phase-change material can moreover move freely in the cavity under
the influence of movements of the plate, whereby the release of
heat to the plate will decrease and whereby an irregular and/or
varying distribution of weight of phase-change material will occur
in the plate.
SUMMARY OF THE INVENTION
[0004] Embodiments of the invention have the object of providing
phase-change material in a manner such that a better absorption and
release of heat is obtained compared to known applications of
phase-change material as heat storage material.
[0005] A first aspect of the invention relates to a pouch filled
with phase-change material, wherein the pouch comprises a preformed
first wall and second wall. The first wall comprises a bowl-shaped
part, in which the phase-change material is accommodated, and a
peripheral part, wherein the second wall is attached to the
peripheral part of the first wall. A high vacuum prevails in the
pouch, and the pouch is intended for placing against a wall to be
heated or cooled.
[0006] By providing the phase-change material in a filled pouch the
freedom of movement of the phase-change material is limited by the
pouch. Because a high vacuum prevails in the pouch, wherein a
pressure of between 1.times.10.sup.-1 and 1.times.10.sup.-7 Pa
typically prevails in the pouch, thermally insulating air is
prevented from being able to lodge between the phase-change
material and the walls of the pouch, or between different parts of
the phase-change material. The phase-change material in the vacuum
pouch is moreover protected from possible contaminants, protected
against possible degradation of the phase-change material, and
igniting of the phase-change material is avoided by the vacuum
pouch. The high vacuum in the pouch can be achieved by providing a
preformed first wall of the pouch with a bowl-shaped part and a
peripheral part, so that the phase-change material can be placed in
the bowl-shaped part, wherein the second wall is attached to the
peripheral part of the first wall immediately after vacuum has been
drawn in the pouch. The advantage of the preformed first wall with
bowl-shaped part is that vacuum can be drawn in simple manner in
the pouch and that a higher vacuum can be achieved when compared to
the use of phase-change material between two flat walls. The first
wall and second wall of the pouch can be attached to each other in
different ways at the peripheral part of the first wall, such as by
means of welding, glueing and so on.
[0007] In a preferred embodiment the pouch is elastic and flexible
to an extent such that the pouch can also stretch when the
phase-change material expands during transition from the one phase
to the other, and such that the pouch becomes taut again when the
phase-change material contracts during a reverse phase transition.
In combination with the high vacuum in the pouch, the flexibility
of the pouch provides for the largest and most efficient possible
contact surface between the phase-change material in the pouch and
the wall to be heated or cooled without the phase-change material
being able to escape or move away from the wall. In a possible
embodiment the walls of the pouch are not elastic, and the wall of
the pouch remote from the wall to be heated or cooled has a surface
area such that an expansion of the phase-change material is
possible.
[0008] In a preferred embodiment of the pouch filled with
phase-change material the first wall and the second wall are at
least 40 .mu.m thick, preferably between 50 .mu.m and 150 .mu.m
thick. Walls of such thickness ensure that the pouch provides a
high degree of protection and strength. Such wall thicknesses
moreover allow preforming of the first and/or second wall of the
pouch, and allow a bowl-shaped part to be provided in the first
wall in which the phase-change material can be placed. It will be
apparent to the skilled person that the first and second walls can
have mutually differing thicknesses. The second wall in particular
is preferably not too thick in order to guarantee a good heat
transfer to the part to be heated or cooled.
[0009] In an exemplary embodiment of the pouch filled with
phase-change material the first wall is a first film and the second
wall is a second film. The first film and second film can have the
same thickness, but can also have mutually differing thicknesses.
Films have the advantage that they can be laminated in advantageous
manner, whereby different material properties can be combined in
one film. The bowl-shaped part in the first wall is preferably
formed in the case of a film by thermoforming.
[0010] In an exemplary embodiment of the pouch filled with
phase-change material the first wall and the second wall comprise a
plurality of layers. The first wall and second wall can comprise
the same layers, although the first and second walls can also
comprise mutually differing layers. Depending on the intended use
of the pouch, it may be useful for the material properties of the
first wall to differ from the material properties of the second
wall. It may thus be advantageous for instance to provide the wall
of the pouch not intended for placing against the wall to be heated
or cooled, and which is therefore remote from the wall to be heated
or cooled, with an additional thermally insulating layer.
[0011] In a preferred embodiment of the pouch filled with
phase-change material the first wall and the second wall comprise a
welding layer and a barrier layer, wherein the welding layer of the
first wall is welded to the welding layer of the second wall.
[0012] The barrier layer is selected such that it does not allow
passage of molecules of the phase-change material, particularly at
higher temperatures at which the phase-change material becomes
liquid. The welding layer is selected such that it is weldable in
simple manner, whereby the first wall and second wall can be welded
to each other at the peripheral part of the first wall.
[0013] In an exemplary embodiment the welding layer comprises
polypropylene and the barrier layer comprises polyamide.
[0014] In an exemplary embodiment of the pouch filled with
phase-change material the first wall and/or second wall comprises a
layer manufactured from aluminium.
[0015] In an exemplary embodiment of the flexible pouch filled with
phase-change material the first wall and/or the second wall are
injection-moulded pieces or part of one injection-moulded piece.
These can for instance be manufactured from silicone.
[0016] In a preferred embodiment the pouch is intended for placing
with the second wall against the wall to be heated or cooled,
wherein the first wall has better thermally insulating properties
than the second wall.
[0017] When the second wall is placed against the wall to be heated
or cooled, it is advantageous that the second wall interferes as
little as possible with the absorption and release of heat by the
phase-change material, and so facilitates the exchange of heat as
well as possible. Conversely, it is advantageous that the first
wall, which is not located against the wall to be heated or cooled,
allows the least possible loss of heat from the direction of the
wall to be heated or cooled, and so is thermally insulated as well
as possible.
[0018] In a preferred embodiment the pouch is filled with
phase-change material not accommodated in capsules.
[0019] The use of phase-change material accommodated in micro- or
macro-capsules is known. A higher heat capacity can however be
obtained by making use of phase-change material not accommodated in
capsules when compared to the same amount of material accommodate
in capsules. This is because air is often present between the
capsules, and this results in a thermally insulating effect.
Phase-change material not accommodated in capsules can moreover be
placed in simple manner in a pouch of appropriate form, whereby a
more efficient contact surface can be obtained for heat exchange
when compared to phase-change material accommodated in
capsules.
[0020] In an exemplary embodiment of the pouch filled with
phase-change material the second wall is a preformed wall. The
second wall can for instance be adapted in advantageous manner to a
shape of the wall to be heated or cooled, whereby the second wall
can be placed in efficient manner against the wall to be heated or
cooled. In the case of a coffee or tea cup the pouch with a
preformed second wall can advantageously be arranged simultaneously
against a bottom part of a part to be heated and against an upright
side part of the part to be heated. It will be apparent to the
skilled person that the same principle can be applied for any
random shape of the wall to be heated or cooled, wherein the pouch
has a preformed second wall with a corresponding shape in order to
guarantee good contact between the second wall of the pouch and the
wall to be heated or cooled.
[0021] The measures and advantages associated with the above
described embodiments of the pouch filled with phase-change
material according to the first aspect of the invention are
likewise applicable to a piece of crockery provided with a flexible
pouch filled with phase-change material and to a method for
manufacturing a pouch filled with phase-change material in
accordance with respectively a second and third aspect of the
invention as described below.
[0022] Provided according to a second aspect of the invention is a
piece of crockery which is provided with the pouch according to any
of the above described embodiments, wherein the pouch is situated
in the crockery and wherein the pouch is placed against a part of
the crockery to be heated or cooled. The second wall is preferably
arranged here against the part of the crockery to be heated or
cooled, preferably crockery of ceramic material such as
earthenware, chinaware or glass. In the case of a plate this plate
can take a double-walled form with an upper wall to be heated or
cooled, and a lower wall. The pouch is then preferably arranged
between the lower wall and the upper wall, wherein the second wall
is arranged against the upper wall to be heated or cooled, while
the first wall is located at a distance from the lower wall such
that it is not heated, or hardly so.
[0023] A third aspect of the invention relates to a method for
manufacturing a pouch filled with phase-change material, wherein
the method comprises of: [0024] shaping a first wall of the pouch
such that the first wall comprises a bowl-shaped part and a
peripheral part; [0025] placing the phase-change material in the
bowl-shaped part of the shaped first wall; [0026] attaching a
second wall of the pouch to the peripheral part of the shaped first
wall such that the phase-change material is situated between the
first and second walls, and that a high vacuum prevails in the
pouch.
[0027] Providing the first wall with a bowl-shaped part enables
easy arrangement of the phase-change material in the bowl-shaped
part, wherein the second wall can then be placed as a cover
connecting to the first wall. This allows sealing of the whole in
simple and reliable manner.
[0028] According to an exemplary embodiment of the method for
manufacturing a pouch filled with phase-change material, the
shaping of the first wall of the pouch comprises of thermally
preforming the first wall of the pouch. The first wall can for
instance then be a film which is thermally preformed.
[0029] In an alternative embodiment the shaping of the first wall
of the pouch comprises of preforming the first wall of the pouch in
a mould by means of underpressure.
[0030] According to an alternative exemplary embodiment, the
shaping of the first wall comprises of injection moulding the first
wall.
[0031] According to a preferred embodiment of the method for
manufacturing a pouch filled with phase-change material, attaching
the second wall to the peripheral part of the shaped first wall
comprises the following steps of: [0032] positioning the first and
second wall relative to each other such that the second wall is
attachable at the peripheral part of the first wall; [0033] drawing
a vacuum in the space between the first wall and the second wall;
and [0034] sealing the pouch at the peripheral part of the first
wall.
[0035] Providing the first wall with a bowl-shaped part enables the
phase-change material to be arranged easily in the bowl-shaped
part, wherein the second wall can then be placed as a cover
connecting to the first wall. This allows a vacuum to be drawn in
simple and reliable manner in the whole entity.
[0036] According to an exemplary embodiment, sealing of the pouch
at the peripheral part of the first wall comprises of welding or
glueing the second wall to the peripheral part of the first
wall.
[0037] According to an exemplary embodiment, placing of the
phase-change material in the bowl-shaped part of the shaped first
wall comprises of melting the phase-change material, casting the
molten phase-change material in a mould and, after cooling, placing
the hardened phase-change material in the bowl-shaped part. This
simplifies creation of a vacuum in the space between the first and
second walls.
[0038] According to an exemplary embodiment, the method for
manufacturing a pouch filled with phase-change material comprises
of shaping the second wall of the pouch prior to the attachment.
The second wall can in this way be given a shape which is adapted
to the shape of the part against which the second wall must be
placed.
[0039] According to an exemplary embodiment, the shaping of the
second wall comprises of injection moulding the second wall or
thermally preforming the second wall.
[0040] In an alternative embodiment the shaping of the second wall
of the pouch comprises of preforming the second wall of the pouch
in a mould by means of underpressure.
BRIEF DESCRIPTION OF THE FIGURES
[0041] The above stated and other advantageous properties and
objectives of the invention will become more apparent, and the
invention better understood, on the basis of the following detailed
description when read in combination with the accompanying
drawings, in which:
[0042] FIG. 1 shows a cross-section of an exemplary embodiment of a
pouch filled with phase-change material according to the
invention;
[0043] FIG. 2 shows a cross-section of an exemplary embodiment of a
pouch filled with phase-change material according to the invention,
wherein the first and second wall comprise a plurality of
layers;
[0044] FIG. 3 shows a cross-section of an alternative embodiment of
a pouch filled with phase-change material according to the
invention, wherein the first wall of the pouch has better thermally
insulating properties than the second wall of the pouch;
[0045] FIG. 4 shows a cross-section of an exemplary embodiment of a
pouch filled with phase-change material according to the invention,
wherein the second wall of the pouch is a preformed wall;
[0046] FIGS. 5A and 5B show respective simplified views of
exemplary embodiments of a piece of crockery provided with a pouch
filled with phase-change material; and
[0047] FIG. 6 shows a schematic overview of an embodiment of a
method for manufacturing a pouch filled with phase-change material
according to the invention; and
[0048] FIGS. 7A, 7B, 7C and 7D illustrate schematically the steps
of a more detailed embodiment of a method for manufacturing a pouch
filled with phase-change material.
DETAILED EMBODIMENTS
[0049] A first embodiment of a pouch filled with phase-change
material according to the invention is illustrated in FIG. 1. This
is a pouch 100 filled with phase-change material 130, wherein pouch
100 comprises a preformed first wall 110 and a second wall 120. The
first wall comprises a bowl-shaped part 111, in which the
phase-change material 130 is accommodated, and a peripheral part
112, wherein second wall 120 is attached to peripheral part 112 of
first wall 110. Bowl-shaped part 111 is shown schematically and as
being angular in the figures, although it will be apparent to the
skilled person that in practical embodiments bowl-shaped part 111
can be "rounder". The attachment location is indicated in
simplified manner in FIG. 1 with strips 115 at peripheral part 112
of first wall 110. First wall 110 and second wall 120 can be
attached to each other in different ways. Walls 110, 120 can be
welded, glued, clamped etc, to each other. A high vacuum prevails
in pouch 100, and pouch 100 is intended for placing against a wall
to be heated or cooled. At high vacuum a pressure of between
1.times.10.sup.-1 and 1.times.10.sup.-7 Pa prevails in the pouch.
The phase-change material used can be any known phase-change
material and, depending on the intended use, a specific
phase-change material can be preferred to another phase-change
material. A phase-change material can thus be selected for instance
on the basis of the melting point thereof, since a higher or lower
melting point can be advantageous for optimum heating or cooling of
liquids or foods. Organic phase-change materials on the basis of
paraffins are particularly suitable for use in a pouch 100 filled
with phase-change material 130 according to embodiments of the
invention.
[0050] Pouch 100 is preferably filled with phase-change material
130 not accommodated in capsules. Non-encapsulated phase-change
materials, or so-called pure phase-change materials, can for
instance be obtained by melting phase-change material in granular
form to a desire shape. Although the use of phase-change material
130 accommodated in micro- or macro-capsules is known, this is
disadvantageous because a thermally insulating air layer may be
present between the capsules. By making use of phase-change
material 130 not accommodated in capsules, a higher heat capacity
can as a result be obtained when compared to the same amount of
phase-change material accommodated in capsules. Phase-change
material 130 not accommodated in capsules can moreover be placed in
simple manner in a suitable form in a pouch, whereby a more
efficient contact surface can be obtained for heat exchange between
the pouch and the wall to be heated or cooled when compared to
phase-change material accommodated in capsules.
[0051] Walls 110, 120 of pouch 100 can comprise different materials
just as long as the walls 110, 120 can keep the phase-change
material 130 contained. The freedom of movement of phase-change
material 130 is thus limited by pouch 100. The pouch is preferably
elastic and flexible to an extent such that pouch 100 can also
stretch when phase-change material 130 expands at the transition
from the solid phase to the liquid phase, and such that pouch 100
becomes taut again when phase-change material 130 contracts during
a reverse phase change.
[0052] In a preferred embodiment of pouch 100 filled with
phase-change material 130 the first wall 110 and second wall 120
are at least 40 .mu.m thick, preferably between 50 .mu.m and 150
.mu.m thick. Walls 10, 120 of such thickness ensure that pouch 100
provides a high degree of protection and strength and/or that pouch
100 is sufficiently flexible. Such wall thicknesses moreover allow
thermal preforming of first 100 and/or second wall 120 of the pouch
and allow a bowl-shaped part 111 to be provided in first wall 110
in which phase-change material 130 can be placed. The first 110 and
second wall 120 can have mutually differing thicknesses.
[0053] It is noted that FIG. 1 is not drawn to scale. In a typical
embodiment the bowl-shaped part 111 will have a depth d of between
1 mm and 20 mm, while the dimension a of the bottom of bowl-shaped
part 111 can be many times larger and is typically adapted to the
piece of crockery for which the pouch is intended. For a large
plate the dimension a can for instance lie between 25 cm and 40
cm.
[0054] In an exemplary embodiment of pouch 100 filled with
phase-change material 130 the first wall 110 is a first film and
second wall 120 is a second film. The first film and second film
can have the same thickness but can also have mutually differing
thicknesses. When first wall 110 is a film, first wall 110 can be
preformed by means of thermal preforming such that first wall 110
comprises a bowl-shaped part 111 and peripheral part 112. Films
have the advantage that they can be laminated in advantageous
manner, whereby different material properties can be combined in
one film. Embodiments of the pouch filled with phase-change
material 130, wherein the walls or films 110, 120 comprise
different layers, will be discussed in more detail with reference
to FIG. 2.
[0055] The preformed first wall 110 and/or second wall 120 of pouch
100 need not be films, but can for instance also be
injection-moulded pieces. First wall 110 can for instance be
injection moulded in a specific form such that first wall 110
comprises a bowl-shaped part 111 and a peripheral part 112. The
first and/or second wall 110, 120 of pouch 100 can thus consist for
instance of injection-moulded silicone or other plastics.
[0056] FIG. 2 illustrates an exemplary embodiment of pouch 200
filled with phase-change material 230, wherein first wall 210 and
second wall 220 comprise a plurality of layer 210a, 210b, 220a,
220b. The layers within the same wall are separated from each other
in FIG. 2 by means of a broken line. First wall 210 and second wall
220 can comprise the same material layers, although the first and
second walls can also comprise mutually differing material layers
210a, 210b, 220a, 220b. Depending on the intended use of pouch 200,
it may be useful for the material properties of first wall 210 to
differ from the material properties of second wall 220. It may thus
be advantageous for instance to provide the wall of pouch 200 not
intended for placing against the wall to be heated or cooled, and
which is therefore remote from the wall for heating or cooling,
with an additional thermally insulating layer.
[0057] In a preferred embodiment of pouch 200 filled with
phase-change material 230 the first wall 210 and second wall 210
comprise a welding layer 210b, 220b and a barrier layer 210a, 220a,
wherein welding layer 210b of first wall 210 is welded to welding
layer 220b of second wall 220. Barrier layer 210a, 220a is selected
such that it does not allow passage of molecules of phase-change
material 230, particularly at higher temperatures at which
phase-change material 230 becomes liquid. Welding layer 210b, 220b
is selected such that it is weldable in simple manner, whereby
first wall 210 and second wall 220 can be welded to each other at
peripheral part 212 of the first wall. A material which is
particularly suitable as welding layer 210b, 220b because of its
high weldability is polypropylene. A material which is particularly
suitable as barrier layer 210a, 220a, because of the low
permeability in respect of phase-change material and the high
resistance at high temperatures, is polyamide. According to a
preferred embodiment, the combined thickness of welding layer 210b,
220b and barrier layer 210a, 220a lies between 60 .mu.m and 100
.mu.m per wall 210, 220. At a thickness within this interval the
walls 210, 220 display high resistance to cutting. This is
advantageous for instance when pouch 200 is used in a piece of
crockery, such as a plate, wherein the high resistance to cutting
provides protection against for instance fragments of the plate if
the plate were to break, and ensures that phase-change material 230
remains intact in pouch 200.
[0058] In an exemplary embodiment of pouch 200 filled with
phase-change material 230 the first wall 210 and/or second wall 220
comprises a layer manufactured from aluminium. A pouch can for
instance thus be formed in advantageous manner which consists of a
welding layer, for instance of polypropylene, laminated with an
aluminium foil. The aluminium foil ensures that the pouch is
substantially impermeable to molecules.
[0059] FIG. 3 illustrates a preferred embodiment of pouch 300
filled with phase-change material 330, wherein pouch 300 is
intended to be placed with second wall 320 against the wall to be
heated or cooled, wherein first wall 310 has better thermally
insulating properties than second wall 320. When second wall 320 is
placed against the wall to be heated or cooled, it is advantageous
that second wall 320 interferes as little as possible with the
absorption and release of heat by phase-change material 330, and so
facilitates the exchange of heat as well as possible. Conversely,
it is advantageous that first wall 310, which is not located
against the wall to be heated or cooled, allows the least possible
loss of heat from the direction of the wall to be heated or cooled,
and so is thermally insulated as well as possible. FIG. 3 shows by
way of example that first wall 310 has two layers 308, 309. Layer
308 corresponds for instance to one of the above mentioned layers
or materials, wherein layer 309 can be an extra thermally
insulating layer. It will be apparent to the skilled person that
the first wall can also consist of a plurality of layers or of only
one layer, wherein first wall 310 has better thermally insulating
properties than second wall 320.
[0060] FIG. 4 illustrates an exemplary embodiment of pouch 400
filled with phase-change material 430 wherein second wall 420 is a
preformed wall. The second wall can for instance be adapted in
advantageous manner to a shape of the wall to be heated or cooled,
whereby second wall 420 can be placed in efficient manner against
the wall to be heated or cooled. In the shown exemplary embodiment
second wall 420 is formed in the shape of a dish. This shape can be
advantageous for placing second wall 420 in efficient manner
against a bottom wall part of a cup or mug to be heated or cooled
as shown in simplified manner in FIG. 5A. The preformed second wall
420 can however also have other shapes depending on the intended
use. It will be apparent to the skilled person that the same
principle can be applied for any shape of the wall to be heated or
cooled, wherein the pouch has a preformed second wall with a
corresponding shape in order to guarantee good contact between the
second wall of the pouch and the wall to be heated or cooled. When
second wall 320 is not preformed, but is a flat wall as shown in
FIG. 3, the pouch is for instance particularly suitable for placing
with second wall 320 against the flat or plane wall of a plate or
oven dish, as shown in simplified manner in FIG. 5B. It will be
apparent to the skilled person that the illustrated shapes of the
preformed first wall 110, 210, 310, 410 and/or preformed second
wall 420 are examples, and that the preformed first wall 110, 210,
310, 410 and preformed wall 420 can also haves other shapes. The
preformed first wall 110, 210, 310, 410 makes it possible to obtain
a high vacuum in pouch 100, 200, 300, 400.
[0061] FIGS. 5A and 5B illustrate exemplary embodiments of a piece
of crockery 500a, 500b provided with a pouch 510 filled with
phase-change material 530 as according to any of the foregoing
embodiments, wherein pouch 510 is situated in the crockery 500a,
500b and wherein pouch 510 is placed against a wall 521 to be
heated or cooled of the crockery 500a, 500b. FIGS. 5A and 5B are
simplified representations and illustrate the use of pouch 510 in a
piece of crockery 500a, 500b.
[0062] FIG. 5A shows particularly a cup or mug 500a intended as
recipient for hot or cold beverages 540. Cup 500a is double-walled
and a pouch 510 filled with phase-change material 530 is provided
in the space between the two walls. The wall 521 of cup 500a to be
heated or cooled is situated between pouch 510 and beverage 540.
The pouch 510 shown in FIG. 5A corresponds to the embodiment shown
in FIG. 4, wherein second wall 420 is preformed. Because of the
preformed second wall 420 pouch 510 can be placed in fitting manner
against wall 521 to be heated or cooled so that pouch 510 makes
contact not only with the bottom but also at least a part of the
upright inner wall of the cup. Not only does pouch 510 filled with
phase-change material 530 hereby release heat via the bottom of
wall 521 to be heated, but also along the upright sides thereof,
whereby the hot beverage 540 can remain hot for longer.
[0063] FIG. 5B shows in particular a plate 500b which has a wall
521 to be heated or cooled which is intended for serving or
presenting foods. Plate 500b is double-walled and a pouch 510
filled with phase-change material 530 is provided in the space 520
between the two walls of the plate. Pouch 510 is thus situated at
the inner side of the wall 521 of plate 500b to be heated or
cooled. Pouch 510 shown in FIG. 5B corresponds to an embodiment
wherein second wall 120, 220, 230 is flat as shown in FIG. 1, 2 or
3.
[0064] Although FIGS. 5A and 5B show only a cup 500a and a plate
500b provided with a pouch 510 filled with phase-change material
530 with a preformed first wall, it will be apparent to the skilled
person that the principle of the invention can be applied to
diverse types of crockery with a wall to be heated or cooled, such
as oven dishes, cups, dessert plates, soap bowls, dessert coupes,
pizza plates, spoons and so on. A pouch 510 filled with
phase-change material 530 with a preformed first wall according to
the invention can also be used for other applications where a wall
has to be cooled or heated, such as in the case of baths or
swimming pools and the like.
[0065] FIG. 6 shows a flow chart of a method 600 for manufacturing
a pouch filled with phase-change material according to the
invention, wherein the method 600 comprises the following steps of:
[0066] step 610 of shaping a first wall of the pouch such that the
first wall comprises a bowl-shaped part and a peripheral part;
[0067] step 620 of placing the phase-change material in the
bowl-shaped part of the shaped first wall; [0068] step 630 of
attaching a second wall of the pouch to the peripheral part of the
shaped first wall such that the phase-change material is situated
between the first and second walls and that a high vacuum prevails
in the pouch.
[0069] Shaping of the first wall can take place in different ways.
According to an exemplary embodiment of the method 600 for
manufacturing a pouch filled with phase-change material, step 610
of shaping the first wall of the pouch comprises of thermal
preforming of the first wall of the pouch. When the first wall is a
film, it can particularly be shaped by means of thermal preforming.
The preformed first wall can have different shapes. Depending on
the intended use of the pouch, a specific shape can be preferred to
another shape. The dimensions can further be adapted to the
intended use. An alternative manner of shaping the first wall is by
injection moulding of the first wall. A first wall can for instance
thus be injection moulded in silicone or other suitable
plastic.
[0070] According to an exemplary embodiment, step 620 of method 600
comprises of melting the phase-change material, casting the molten
phase-change material in a mould and, following cooling, placing
the phase-change material in the bowl-shaped part, for instance
phase-change material which has hardened in the form of a disc.
First melting for instance granulates of phase-change material
enables the phase-change material to be brought into a desired
shape by casting the molten phase-change material in a mould as
desired. Following cooling, the shaped phase-change material can
then be placed in the bowl-shaped part of the first wall, and the
phase-change material can be packed under high vacuum between the
first and second wall of the pouch.
[0071] According to a preferred embodiment, step 630 of method 600
comprises the following steps. During a first step the first and
second walls are positioned relative to each other such that the
second wall can be attached at the peripheral part of the first
wall. When the first and second walls are in position for
attachment, a vacuum is drawn in the space between the first wall
and the second wall and, substantially instantaneously after
applying the vacuum, the pouch is sealed at the peripheral part of
the first wall. Drawing a vacuum in the space between the first and
second walls takes place for instance by providing tubes between
the first and second walls, by means of which vacuum is draws in
the space. It will however be apparent to the skilled person that
alternative ways can be employed to draw a vacuum in the pouch.
[0072] The sealing of the pouch at the peripheral part of the first
wall can also take place in different ways. According to an
embodiment, the pouch is sealed by welding the second wall to the
first wall at the peripheral part of the first wall. According to
an alternative embodiment, the pouch is sealed by glueing the
second wall to the first wall at the peripheral part of the first
wall. It will be apparent to the skilled person that other ways can
be employed to seal the pouch.
[0073] According to an exemplary embodiment, the method 600 for
manufacturing a pouch filled with phase-change material comprises
of shaping the second wall of the pouch prior to attachment.
Shaping of the second wall can take place in different ways.
According to an exemplary embodiment, shaping of the second wall of
the pouch comprises of thermally preforming the second wall of the
pouch. When the second wall is a film, it can particularly be
shaped by means of thermal preforming. The preformed second wall
can have different shapes. Depending on the intended use of the
pouch, a specific shape can be preferred to another shape. An
alternative manner of shaping the second wall is by injection
moulding the second wall. A second wall can for instance thus be
injection moulded in silicone or other suitable plastic.
[0074] FIGS. 7A, 7B, 7C and 7D illustrate schematically the steps
of a more detailed embodiment of a method for manufacturing a pouch
filled with phase-change material. In a first step (FIG. 7A) a
first wall is provided in the form of a round first film 710. In a
second step (FIG. 7B) first film 710 is thermally performed such
that the first wall comprises a bowl-shaped part 712 and a
peripheral part 711. In a third step (FIG. 7C) a phase-change
material 730, here in the form of a preformed disc, is placed in
bowl-shaped part 712 of the shaped first film 710. The shape and
dimensions of preformed disc 730 preferably substantially
correspond to the shape and dimensions of bowl-shaped part 712. In
a fourth step (FIG. 7D) a second round film 720 is placed as a
cover on first film 710 with interposing of a tube 750 for the
purpose of drawing a vacuum in the space between first film 710 and
second film 720. Peripheral part 712 of the shaped first film 710
is welded against a peripheral part 722 of second film 730 in order
to form the pouch, while tube 750 is retracted.
[0075] The skilled person will appreciate that the invention is not
limited to the above described embodiments, and that many
modifications and variants are possible within the scope of the
invention, which is defined solely by the following claims.
* * * * *