Note: Descriptions are shown in the official language in which they were submitted.
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The invention relates to a latent heat body with
paraffin-based latent heat storage material held in a
carrier material which has holding spaces.
A porous foam material as carrier material is known
from German utility model 84 08 966. However, with this
foam material it is impossible to achieve the
structural strength which is desired even in the heated
state of the latent heat storage material. Moreover,
the porous foam material cannot readily be impregnated
with the latent heat storage material, but rather
special measures, such as squeezing, have to be taken.
A latent heat body in which furthermore the carrier
material is assembled from individual carrier material
elements, for example by adhesive bonding, capillary-
like holding spaces for the latent heat storage
material being formed at any rate between the carrier
material elements, is also known from PCT/EP 98/01956,
which is not a prior publication. The content of this
document is hereby also incorporated in its entirety in
the disclosure of the present application, partly with
a view to including features of this document in claims
of the present application.
Working on the basis of the abovementioned German
utility model 84 08 966, the invention is based on the
object of providing a latent heat body which, while
being simple to produce, is highly effective, i.e. has
a high heat storage capacity, and which at the same
time has sufficient structural strength even in the
heated state and in particular satisfies high static
demands. Furthermore, it is desired for the carrier
material to as far as possible automatically fill
itself with or suck up the latent heat storage material
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and to have a high retention capacity for latent heat
storage material.
This object is initially and substantially achieved
S with the subject matter of claim 1, in which it is
provided that capillary holding spaces for the latent
heat storage material are formed inside the carrier
material and that the carrier material contains a
mineral substance with an open capillary pore
structure. For a mineral substance of this type,
consideration is given to an absorbent solid structure,
preferably comprising a gypsum material or a clay
material or calcareous sandstone or siliceous earth
(dolomite earth) or any desired combinations of these
materials. Preferred starting products are untreated
gypsum plates, gypsum granules, siliceous earth
granules (dolomite earth). In addition to being
universally available and being inexpensive raw
materials, these products satisfy high static demands,
fire prevention requirements and have a relatively high
thermal conductivity. Compared with latent heat bodies
having a carrier material consisting of fibers, latent
heat bodies with solid structures of this type
generally have a lower proportion by mass of latent
heat storage material, which is nevertheless sufficient
for numerous uses, paraffin preferably being used as
latent heat storage material, although stearin, fat or
similar substances can also be used. Compared with
latent heat bodies with a higher proportion by mass of
latent heat storage material, the result for the latent
heat body according to the invention is a cost benefit,
in particular in view of the low raw material costs of
the carrier material. Nevertheless, it is also
possible, in a latent heat body according to the
invention, for the carrier material, in addition to a
mineral substance, also to contain fiber elements,
which are preferably disposed in distributed manner in
the carrier material. The fiber elements may in
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principle consist of organic and/or inorganic materials
and may be selected in particular from the materials
mentioned in PCT/EP 98/01956. In this context, examples
mentioned are organic materials, such as plastics,
cellulose, or wood, ceramic, mineral wool, plastics,
cotton or wool. Fiber elements made from plastics
preferably have base materials such as polyester,
polyamide, polyurethane, polyacrylonitrile or
polyolefins. In general terms, it is also possible to
use fiber elements made from various materials with
very different lengths and very different diameters in
any desired combinations. A carrier material which, in
addition to a mineral substance with an open capillary
pore structure, i.e. an absorbent solid structure, also
contains fiber elements can, depending on the selected
proportions by mass, have properties which are
optimized for a particular usage. For example, adding
fiber structures generally effects an increased storage
capacity for latent heat storage material and a
reduction in the thermal conductivity. The latter
simultaneously leads to an increase in the storage
emission time, i.e. to the heat transfer being slowed,
which in many uses offers advantages. Furthermore, the
mineral substance with the open capillary pore
structure and the fiber elements may also differ in
further materials properties or features, such as for
example the density, the heat storage capacity, the
coloring and the like, so that controlled adaptation of
the carrier material to the particular intended use is
possible by suitable selection of corresponding
quantitative proportions. Overall, it becomes clear
that a combination of this type considerably increases
the range of uses of carrier material.
It is particularly preferred for the latent heat
storage material to be a paraffin or to be based on
such a paraffin, as described in DE-A 43 07 065. The
content of this prior publication is hereby
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incorporated in its entirety into the disclosure of the
present application, partly with a view to including
features of this prior publication in claims of the
present application. In a preferred embodiment, the
proportion by mass of the latent heat storage material,
based on the total mass of the latent heat body, is
between 5 and 50%, preferably 250 or further preferably
40 to 500. The open capillary pore structures, which on
account of their capillary sucking action are also
designated as "sucking structures", in an advantageous
embodiment are formed in such a way that a preferably
uniformly distributed residual air volume remains
therein, which absorbs temperature-dependent changes in
volume of the latent heat storage material of
preferably at most 10% of the latent heat storage
material volume. Temperature expansion of the
abovementioned order of magnitude is associated with
conventional maximum overheating compared with the
melting temperature of the latent heat storage material
of 30 to 40°K, so that, on account of these
temperature-dependent volume changes being absorbed or
compensated for by the residual air volumes, under
these conditions there is no sweating of the latent
heat storage material out of the carrier material.
Nevertheless, the latent heat body according to the
invention may be adapted to specific usages by a latent
heat storage material with additives contained therein,
such as preferably thickening agents and/or a
proportion of mineral oils and polymers and/or others
of the additives mentioned in PCT/EP 98/01956 and/or
DE-A 43 07 065, in such a manner that even in the event
of the melting or phase transition temperature being
exceeded by more than the levels stated above there is
no possibility of the latent heat storage material
sweating out of the carrier material. As an alternative
or in combination, the latent heat body can have a
sheath, which preferably consists of a film/foil
material, such as for example plastics film or aluminum
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- foil. In this context, consideration is given in
particular to a sheath which is impermeable to latent
heat storage material. However, for certain usages it
may also be advantageous for the sheath to be formed
with a controlled permeability for latent heat storage
material, for example by introducing small pores into a
film/foil material which is impermeable to latent heat
storage material, leading to a desired "breathing
activity" of the sheath. Breathing activity of this
type may, for example, be advantageous when the latent
heat body additionally contains a hygroscopic material,
since the possibility then exists of withdrawing the
moisture which has been bonded to the hygroscopic
material from the environment of the latent heat body.
In this context, the disclosure content of
DE 198 36 048.7 is also completely incorporated in the
present application, partly with a view to including
features described therein in claims of the present
application.
Consideration is initially given to the carrier
material being formed in a latent heat body as a
cohesive structure, i.e. to a cohesive body with
capillary holding spaces for the latent heat storage
material contained therein being formed from the
mineral substance with the open capillary pore
structure and the fiber elements which may additionally
be contained therein. A carrier material which is
formed from a mineral substance with an open capillary
pore structure and from fiber elements can contain
capillary holding spaces produced by the capillary pore
structure alone and/or capillary holding spaces formed
by fiber elements adjoining one another and/or
capillary holding spaces formed by mineral substance in
combination with fiber elements. In this case, in the
context of the invention the term open capillary pore
structure is understood as meaning a pore structure
which, in terms of its openness, has connections
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between the individual pores and between the pores
which lie in the vicinity of the surface or edge and
the surrounding environment and which in terms of its
capillary action exercises an automatic sucking action
on latent heat storage material. According to the
invention, an open capillary pore structure is also
obtained with a carrier material which, in addition to
a mineral substance, also contains fiber elements. The
pores or capillary holding spaces may in particular be
formed in the manner of channels, including with a
variable channel cross section, and/or may also contain
spherical or similar cavities. However, additional
further forms are also conceivable.
As an alternative to a cohesive structure of the
carrier material, in an alternative embodiment of the
latent heat body it is provided that the latter
contains a number of latent heat part-bodies, a latent
heat part-body containing a carrier material part-body
and the latent heat storage material which is held in
the capillary holding spaces contained therein and the
residual air volume which is likewise present in the
capillary holding spaces. The latent heat body
according to the invention or the absorbent solid
structures may, for example, be used in the form of
plates, slabs, building blocks, granules or other forms
for a wide range of tasks . For example, it is possible
to use slabs or building blocks independently or in a
structural assembly (walls). Further possible uses are
a warming plate for foodstuffs, use in combination with
floor heating and a transport container, which are
dealt with in more detail in connection with the
description of the figures.
The invention also relates to a method for producing a
latent heat body with paraffin-based latent heat
storage material held in a carrier material which has
capillary holding spaces. Methods of the generic type
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are known from PCT/EP 98/01956, which is not a prior
publication, and DE 198 36 048.7, which is likewise not
a prior publication. The invention is based on the
object of providing a method with which the
abovementioned latent heat body can be produced easily
and inexpensively. According to the invention, to
achieve the object it is provided that the latent heat
storage material is liquefied, that the previously
liquefied latent heat storage material is conducted to
automatically sucking, capillary-like holding spaces of
the carrier material, and that a carrier material which
contains a mineral substance with an open, capillary
pore structure is used. The carrier material or the
mineral substance and the latent heat storage material
may in this case preferably have one or more of the
features described above in each case. In particular,
it is possible for fiber elements, which may likewise
have one or more of the features listed above in
connection therewith, to be added to the mineral
substance. It is preferred for the fiber elements to be
uniformly distributed in the mineral substance. For
this purpose it is possible, for example, starting from
an initial state of the mineral substance, in which the
latter is present in free-flowing, liquid or pasty
form, for fiber elements to be stirred into the mineral
substance until they have preferably adopted a uniform
dispersion and, in further method steps, for initially
liquefaction and then, by a thermal treatment (firing),
for a desired absorbent solid structure, i.e. an open
capillary pore structure, to be produced.
The liquefaction of the latent heat storage material
can be carried out in a simple way by supplying thermal
energy until the desired degree of liquefaction, up to
possible complete liquefaction of the latent heat
storage material, has been reached. If the previously
liquefied latent heat storage material, in a further
method step, is then conducted to the automatically
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sucking, capillary-like holding spaces of the carrier
material, the capillary sucking action of the open,
capillary pore structure of the carrier material leads
to an automatically occurring, ongoing uptake of the
latent heat storage material in the capillary-like
holding spaces of the carrier material being observed.
Therefore, a substantial advantage of the method
according to the invention is that mechanical action on
the carrier material and the latent heat storage
material for this purpose can be dispensed with
altogether. Rather, the previously liquefied latent
heat storage material is taken up in the carrier
material even when the previously liquefied latent heat
storage material is conducted at zero pressure to the
automatically sucking, capillary-like holding spaces of
the carrier material. In a preferred variant of the
method according to the invention, the latent heat
storage material is introduced into a container, in
which it is liquefied up to a desired level by the
supply of heat, whereupon the carrier material is
immersed in the previously liquefied latent heat
storage material. As a result of the immersion, the
previously liquefied latent heat storage material is
introduced to the automatically sucking capillary
holding spaces of the carrier material, so that it is
automatically taken up in these spaces by the capillary
sucking action. In a further preferred refinement of
the method, the temperature of the latent heat storage
material, while it is being conducted to the
automatically sucking, capillary-like holding spaces of
the carrier material, is regulated by the controlled
supply and/or dissipation of heat. By way of example,
it is possible, when the carrier material is immersed
in the previously liquefied latent heat storage
material, to achieve further liquefaction or a further
reduction in the viscosity of the latent heat storage
material by controlled supply of heat and thus to
promote the uptake into the capillary-like holding
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spaces. On the other hand, it is also possible to bring
about the opposite effect during the immersion, by
dissipation of heat or by cooling the latent heat
storage material, with the result that, for example
after a suitably selected time duration of the
immersion process, slowing or even, if required,
termination of the uptake of further latent heat
storage material can be realized. Furthermore, it is
possible for additives which advantageously influence
the flow characteristics of the latent heat storage
material and/or which advantageously influence the
crystal structure produced during cooling to be added
to the latent heat storage material. By way of example,
a thickening agent and/or a proportion of mineral oils
and polymers may be added to the latent heat storage
material. Furthermore, it is also possible to use
additives as described in DE-A 43 07 065 and/or in
PCT/EP 98/01956. Preferably, with the method according
to the invention a mass or amount of the latent heat
storage material which is between 5 and 50%, preferably
25o and further preferably 40 to 500, of the total mass
of the latent heat body is conducted to the holding
spaces of the carrier material in order to be taken up.
For example, if the specific amount of uptake in a
carrier material per unit time is known for a selected
latent heat storage material in a specific state of
liquefaction, it is possible for the mass of latent
heat storage material taken up into the holding spaces
of the carrier material to be influenced in a
controlled way by suitably selecting the duration of
uptake. Once this duration has expired, it is then
possible to terminate the uptake process by separating
the latent heat storage material which still remains
outside the carrier material from the carrier material,
for example by removing the carrier material from an
immersion bath of the previously liquefied latent heat
storage material. In this context, it is also
preferable for the latent heat body or the carrier
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material, after removal from an immersion bath,
initially to be drip-dried and then cooled to a desired
temperature, for example to ambient temperature, in a
further possible method step. With regard to the
immersion method described above, it is additionally
pointed out that introducing the previously liquefied
latent heat storage material to the carrier material
can also take place in other expedient ways, for
example by dripping latent heat storage material into
the carrier material or by applying, to the carrier
material, a latent heat storage material layer
thickness which is intended to be taken up and may be
defined. In a further method step, it is possible for
the latent heat body to be provided with a sheath,
which may have one or more of the features described
above in connection therewith.
There are numerous possible uses for the latent heat
bodies according to the invention, on account of the
advantageous properties explained above and their
possible variations. They are employed, for example, in
the form of slabs, building blocks or granules, on
their own or in a structural assembly (walls). Further
possible uses in the construction industry are storage
walls, roofs or floor storage heating systems. In this
context, the advantageous effect is achieved that, from
building materials which are "light" in terms of the
heat storage capacity, "heavy" building materials are
obtained by the impregnation or by the uptake of latent
heat storage material, without the layer thickness of
these materials being changed. Furthermore, as emerges
from the following description of preferred exemplary
embodiments, numerous other uses of the latent heat
body according to the invention are conceivable.
In this context, the invention also relates to a
warming plate having a plate base body and having a
formed receptacle for foodstuffs, in particular for
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rice. According to the invention, it is provided that
the plate base body contains a latent heat body with
paraffin-based latent heat storage material which is
held in a carrier material having holding spaces,
capillary holding spaces for the latent heat storage
material being formed inside the carrier material and
the carrier material containing a mineral substance
with an open capillary pore structure. Furthermore, it
is possible for the latent heat body of the warming
plate to have one or more of the features explained
above in connection therewith. In a preferred
configuration, it is provided that one or more
receptacles for foodstuffs have in each case a recess
which is integrated into a surface of the plate base
body. The advantage of the warming plate according to
the invention consists in an inexpensive and simple yet
stable structure and in a highly effective heat storage
action.
The invention also relates to floor heating, in
particular electric floor heating, having a heating
register disposed between a bare floor and a covering,
according to the invention a latent heat body with
paraffin-based latent heat storage material held in a
carrier material which has holding spaces being
provided, capillary holding spaces for the latent heat
storage material being formed inside the carrier
material and the carrier material containing a mineral
substance with an open capillary pore structure.
Furthermore, the latent heat body may have one or more
of the features described above. In particular, it is
possible for the latent heat body to be formed in the
manner of a slab and to be disposed between the bare
floor and the heating register. In a preferred
embodiment, a thermal insulation layer, which may, for
example, be a Styropor layer, is disposed on the top
side of the bare floor. Furthermore, it is preferred
for a first layer with a latent heat body which is
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formed from latent heat part-bodies and may likewise
have one or more of the features explained in
connection with the latent heat body according to the
invention to be disposed between the bare floor and the
heating register. In particular, it is possible for the
first layer described above to be disposed between the
slab-like latent heat body and the heating register. In
an expedient refinement of the floor heating, a second
layer with a latent heat body which is formed from
latent heat part-bodies and may likewise have one or
more of the features as are described in connection
with the latent heat body according to the invention is
provided between the heating register and the covering.
In particular, consideration is given to the latent
heat part-bodies of the first and/or second layer being
formed in the manner of granules. Furthermore, it is
possible for a latent heat storage material with a
phase transition temperature which is different
compared with the latent heat storage material
contained in the latent heat part-bodies of the second
layer to be held in the latent heat part-bodies of the
first layer. In particular, consideration is given to
the phase transition temperature of the latent heat
storage material of the first layer being higher than
the phase transition temperature of the latent heat
storage material of the second layer. The advantageous
properties of the floor heating according to the
invention include its high heat storage capacity and
the associated uniform emission of heat to the room
above it. Furthermore, on account of the structural
property of the latent heat bodies contained therein,
the floor heating satisfies high static demands.
The invention also relates to a transport container
having an outer housing and an inner housing which is
held therein spaced apart by a space. According to the
invention, it is provided that a latent heat body is
disposed in the space, with paraffin-based latent heat
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storage material held in a carrier material which has
holding spaces, capillary holding spaces for the latent
heat storage material being formed inside the carrier
material and the carrier material containing a mineral
substance with an open capillary pore structure. The
latent heat body may furthermore have one or more of
the features explained above in connection therewith.
In an expedient refinement, plate-like latent heat
bodies are held preferably detachably or removably in
the space, at least two latent heat bodies with
different phase transition temperatures of the latent
heat storage material respectively held therein being
disposed adjacently in the direction perpendicular to
the plate plane of the plate-like latent heat bodies.
The invention also relates to a latent heat body
according to the precharacterizing clause of claim 41.
According to this precharacterizing clause, it is a
latent heat body having a carrier material and
paraffin-based latent heat storage material held
therein in capillary holding spaces, the latent heat
body containing a number of latent heat part-bodies and
a latent heat part-body containing a carrier material
part-body and latent heat storage material which is
held therein in capillary holding spaces. A latent heat
body of this type is known from WO 98/53264. To the
extent that this document provides for a latent heat
body to have a number of latent heat part-bodies, the
latent heat part-bodies more or less loosely butt
against one another by means of their outer surfaces,
with air volumes possibly also being included between
the latent heat part-bodies. Starting from this point,
the further subject matter of the invention is based on
the object of developing a latent heat body of the
generic type in a manner which is advantageous for use.
This technical problem is initially and substantially
solved by the characterizing features of claim 41, in
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which it is provided that the number of latent heat
part-bodies together is surrounded by an embedding
material, and that the carrier material contains wood
fibers and/or cardboard and/or granulated siliceous
earth and/or diatomaceous earth. Further materials
which have capillary holding spaces which are suitable
for the invention may also be correspondingly used, so
that the latent heat storage material is in any event
well taken up by the capillary sucking action of the
holding spaces in the carrier material. Furthermore, it
is preferable for a residual air volume which absorbs
temperature-dependent changes in volume of the latent
heat storage material of up to approximately l00 of the
latent heat storage material volume to be present in
the capillary holding spaces. As has already been
described with regard to the first inventive subject of
the present application, the carrier material may
moreover contain fiber elements, preferably in a
uniform distribution. It is also possible for the
latent heat storage material to contain a thickening
agent and/or a proportion of mineral oils and polymers.
It is likewise also possible in a latent heat body as
described in connection with claims 1 to 15 for the
carrier material together with the latent heat storage
material held therein in the capillary holding spaces
to be surrounded, in terms of its outer contours, by an
embedding material. The carrier material may in this
case be formed to be cohesive or may be in the form of
carrier material part-bodies, a carrier material part
body together with the latent heat storage material
held therein and, if necessary, also residual air
volumes held in the capillary holding spaces forming a
latent heat part-body in the sense of the present
application.
Where reference is made to an embedding material, this
material may, for example, be silicone, in particular a
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silicone rubber, resin, concrete, cement, gypsum,
mortar or other materials of similar properties,
mixtures or mixes of a plurality of these substances
also being possible for use as embedding materials. The
selection of the material or materials used as
embedding material may preferably be carried out in
such a manner that, adapting to the carrier material
selected in the individual case, a total hardness or
total rigidity of the latent heat body which is overall
advantageous for the use of the latent heat body is
established. It is also possible, by adapting in
particular carrier material and embedding material, for
the overall resilience, the overall density and further
resultant properties, such as for example thermal
conductivity, heat storage capacity and the like, to be
influenced. The embedding or surrounding of the carrier
material together with latent heat storage material
contained therein in the embedding material is
preferably carried out in the sense of mixing, encasing
or even impregnation with the embedding material
preferably occurring, which overall leads to a
composite. Therefore, within a composite of this type
there is cohesion between the carrier material, the
latent heat storage material held therein and the
embedding material, in which arrangement the carrier
material may be present in cohesive form or in the form
of a plurality of carrier material part-bodies which
are held together in the composite. By means of a
corresponding composite, it is possible, in particular
with an external shaping which is adapted to the
individual case, to form a latent heat body, or
alternatively a latent heat body may also, as explained
in further detail below, be formed from a number of
composites of this type, which together are
incorporated in a matrix material and in the sense of
the invention are also referred to as conglomerates.
Compared with known latent heat bodies, the composite
which is achieved by the embedding therefore in
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particular represents a technical advantage in use,
since in the case of latent heat bodies which comprise
a plurality of latent heat part-bodies, the use of an
outer sheath, for example of a film or foil, for
shaping and holding the bodies together can be
dispensed with. A further technical advantage in use
lies, as mentioned above, in the very fact that, as a
result of the controlled adaptation of the material
used to the carrier material, desired resultant
properties of the latent heat body can be set in a
controlled manner. There is preferably provision for
the proportion of the embedding material in the sum of
the masses of latent heat storage material, carrier
material and embedding material to be at least
approximately 500, lower proportions by mass also being
possible or sensible, depending on the particular use.
Furthermore, it is preferable for the proportion of the
latent heat storage material, based on the joint mass
of latent heat storage material and carrier material,
to lie between approximately 40o and approximately 800,
and preferably to be approximately 600. The proportion
of the latent heat storage material in the total weight
may preferably be approximately 15% to 250. With regard
to the carrier material bodies or latent heat part-
bodies, consideration is preferably given to them being
of granular or fibrous structure and to a typical
geometric dimension of a carrier material part-body or
of a latent heat part-body being of the order of
magnitude of some or a few millimeters to a few
centimeters. Since, depending on the quantitative
proportion added, the latent heat storage material, on
account of the capillary action of the holding spaces,
is situated predominantly in the interior of the
carrier material or the carrier material part-bodies,
in terms of the external shape and dimensions there is
generally no substantial difference between carrier
material part-bodies and latent heat part-bodies.
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Furthermore, it is possible for the latent heat body,
according to one of the variant embodiments proposed
overall hitherto, to contain a number of conglomerates,
which are each formed from a number of carrier material
part-bodies, in which latent heat storage material is
held and which together are surrounded by an embedding
material, the conglomerates together being incorporated
in or surrounded by a matrix material. The carrier
material part-bodies which belong to an individual
conglomerate, on account of the embedding material in
which or by which they are embedded or surrounded
together, are held together, so that, depending on the
preferred number of carrier material part-bodies
enclosed therein and the size of the individual carrier
material part-bodies, conglomerates of different size
which can be adapted to the particular use can be
formed. Materials which are selected from the group
consisting of silicone, in particular silicone rubber,
resin, gypsum, cement and concrete are particularly
suitable as matrix material, combinations of these
materials possibly also being expedient. Consideration
is preferably given to selecting a different material
as the matrix material from that used for the embedding
material. Depending on the individual properties of the
carrier material selected in the individual case, the
embedding material and the matrix material, it is then
advantageously possible, by adapting the quantitative
ratios, to achieve a desired overall property of the
latent heat body; in this context the strength,
hardness, elasticity, thermal conductivity, heat
storage capacity and the like, for example, can be set
in a controlled way as properties. In a preferred
embodiment, the proportion of the matrix material in
the total mass of the latent heat body may be at least
approximately 500.
In one example of use, latent heat part-bodies may be
formed from in each case a shred of cardboard which is
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impregnated with latent heat storage material, with a
proportion by mass of, for example, 40-800, preferably
600, of latent heat storage material, based on the
total mass of the latent heat part-body. A conglomerate
may contain a number of carrier material part-bodies of
this type, which together are embedded in a resin and,
in the process, are enclosed by the resin, so that the
carrier material part-bodies are held together. The
proportion by mass of the latent heat storage material
in the total mass of the conglomerate may, for example,
be approximately 30%. For their part, the conglomerates
described above may, for example, be added to concrete
up to an approximately 50-50 mixing ratio, so that the
proportion by mass of the latent heat storage material
in the latent heat body formed is preferably up to
approximately 150. Variations on this example of use
may consist in silicone being provided instead of the
resin and/or latent heat part-bodies made from
granulated siliceous earth impregnated with latent heat
storage material being provided. Surprisingly, with
embodiments of this type it has emerged that the
structural strength of the concrete is not adversely
affected, but rather under certain circumstances is
even positively affected. For this, it is pertinent
that the carrier material, on account of the above-
described order of magnitude of the carrier material
part-bodies, as a result of the capillary holding
spaces exerts a pronounced sucking action on the latent
heat storage material. While in contrast, for example
when carrier materials in powder form are used, the
latent heat storage material attached thereto would
always also be directly surrounded by the embedding
material and would lead to strength losses therein,
this is effectively avoided by the uptake of the latent
heat storage material in the carrier material part-
bodies which has been explained above. A substantial
advantage of a latent heat body formed from carrier
material, latent heat storage material and embedding
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material as well as, if appropriate, additional matrix
material also consists in the fact that the granules
and/or the fibers of the carrier material additionally
serve as reinforcement and thus increase the static
stability. The importance of the embedding material
(and if appropriate the matrix material) initially
consists in, before its/their crosslinking or curing,
firstly establishing specific, desired free-flowing
properties or easy deformability of the mix formed with
the latent heat part-bodies, for processing, so that
this mix can, for example, be rolled out or cast into a
mold. By contrast, after the crosslinking or curing,
the function involves codetermination of the resultant
abovementioned overall properties of the latent heat
body. All in all, the functions of support material,
latent heat storage material, embedding material and
matrix material are separate from one another, so that
as a further advantage there are no instances of
functions being exceeded. Preferred embodiments of the
latent heat body according to the invention may be
given, for example, in the construction industry, for
example as wall, floor or ceiling panels, as road
coverings, but also as items of clothing, for example
as shoe soles and, moreover, for example as elastic
thin-film elements or prostheses. Depending on the
particular use, the proportion of paraffin-based latent
heat storage material may also amount to 15% to 250 of
the total weight of the latent heat body.
The invention also relates to a method for producing a
latent heat body according to the precharacterizing
clause of claim 57. In this context too, reference is
made to the prior art given in W0.98/53264. Where this
document describes, as a refinement of the production
method, the possibility that the carrier material which
has been impregnated with latent heat storage material
can be divided into a number of latent heat part-
bodies, the document also points out the possibility
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that the latent heat part-bodies of the latent heat
body may be enclosed by a sheath which encloses them
together, for example a film or foil which surrounds
the outer contour of the latent heat body. A latent
heat body which has been manufactured accordingly in
accordance with WO 98/53264 then has a number of latent
heat part-bodies in its interior, which more or less
loosely butt against one another and/or against the
outer sheath by means of their surfaces. Working on the
basis of this, the further subject matter of the
present invention is based on the object of further
developing a method of the generic type for producing a
latent heat body so that it is advantageous for use.
This object is initially and substantially achieved
with the subject matter of claim 57, in which it is
provided that the carrier material which has been
impregnated with latent heat storage material is
surrounded by an embedding material, and that a carrier
material which contains wood fibers and/or cardboard
and/or granulated siliceous earth and/or diatomaceous
earth is used. This method has initially proven
advantageous for use to the extent that a certain
surface sealing of the latent heat body is achieved
without the latent heat body for this purpose having to
be encased by a sheath, for example a film or foil. As
a further advantage it is possible, starting from the
geometric shape of the carrier material impregnated
with latent heat storage material, during the
processing of the embedding material to achieve a
possibly different desired shaping of the latent heat
body, as a result of the embedding material being
processed with correspondingly adapted, possibly
different material thicknesses. The use according to
the invention of a carrier material which contains wood
fibers and/or cardboard and/or siliceous earth granules
and/or diatomaceous earth results, in the desired
manner, in a high capillary sucking action of the
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carrier material on the latent heat storage material
and, to a considerable extent also in conjunction with
a preferably high specific outer area of the carrier
material, in problem-free, durable attachment of the
embedding material to the carrier material containing
latent heat storage material in its holding spaces
being achieved simultaneously. With the proposed
method, it is possible to produce a latent heat body
starting, for example, from an individual carrier
material body, i.e. from a cohesive carrier material. A
carrier material body of this type may, for example, be
a shaped body which contains the carrier material
mentioned above and the geometric shape of which has
already been largely adapted to the shape of the
desired latent heat body in a preceding working step.
For example, it is possible for a shaped body of this
type to be produced by adhesive bonding and/or pressing
of wood fibers and/or cardboard and/or granulated
siliceous earth and/or diatomaceous earth.
Alternatively it is also possible, for example, for a
shaped body of this type to be produced directly from a
cohesive piece of cardboard or siliceous earth or
diatomaceous earth. Alternatively, it is also possible
for the carrier material which has been impregnated
with latent heat storage material, before it is
surrounded with the embedding material, to be
comminuted into latent heat part-bodies, a latent heat
part-body being formed from a carrier material part-
body and latent heat storage material held therein as
well as, if appropriate, residual air volumes which are
likewise held therein. A carrier material which has
been impregnated with latent heat storage material and
is based on the carrier materials. described above may
be used as starting material for this comminution.
Comminution may be achieved, for example, by pulping,
chopping or cutting, but not by pulverizing down to a
powder form. Then, in a further method step, a number
of latent heat part-bodies which are provided for the
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latent heat body may together be surrounded by the
embedding material. With regard to the geometric size
ratios of the latent heat part-bodies, it is pertinent
that these are under no circumstances comminuted down
to the size of powder grains, but rather that the
comminution leads to an order of magnitude in which the
sucking ability of the carrier material is maintained.
With regard to the embedding material, it is generally
preferred for this material, while the carrier material
which has been impregnated with latent heat storage
material is being surrounded therewith, to be processed
into a free-flowing and/or kneadable state or to be
kept in such a state. The processing may preferably
involve a mixing process, mixing of the latent heat
part-bodies with the embedding material, for example by
stirring and/or kneading-in, being possible.
Furthermore, it is preferred for the embedding
material, after the carrier material which has been
impregnated with latent heat storage material has been
surrounded by the embedding material, to be solidified.
This may preferably be carried out by a drying process,
for example with thermal energy being supplied.
Furthermore, it is also possible to bring about a
controlled setting or curing of the embedding material
by physical and/or chemical processes. In a preferred
variant of the proposed process, it is provided that
the latent heat body, before the embedding material
solidifies, is cast into a mold, so that a latent heat
body of corresponding shape is obtained after the
subsequent solidification of the embedding material. As
an alternative or in combination, it is possible for
the latent heat body, before solidification of the
embedding material is brought about, to be rolled out,
so that, for example, elastic thin-film elements can be
obtained.
The described method for producing a latent heat body
can also be modified in such a manner that a
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conglomerate is formed from a number of carrier
material part-bodies with latent heat storage material
held therein by a common surrounding or embedding of
the corresponding latent heat part-bodies in the
embedding material, and that a number of conglomerates
together is incorporated in a matrix material,
conglomerates in the sense of the invention being
understood as meaning assemblies of the type explained
above . In this context it is possible in principle for
the materials which have already been proposed as
embedding material also to be used as matrix material.
The procedure may expediently be such that, after the
processing of the embedding material and shaping of a
conglomerate which is desirable under certain
circumstances, firstly solidification of the embedding
material is brought about, and that in a subsequent
working step a number of conglomerates together is
incorporated in the matrix material. In this case it is
again preferable for the matrix material to be
processed in a free-flowing and/or kneadable form,
while in subsequent method steps initially shaping of
the latent heat body and subsequent solidification of
the matrix material may take place. In a preferred
variant of the proposed method, the procedure is such
that different materials are used as embedding material
and as matrix material. As a result, depending on their
physical and chemical properties, which are generally
likewise different, it is possible, taking into account
the physical and chemical properties of the carrier
material and of the latent heat storage material, by
controlled adaptation of the respective quantitative
proportions, to produce latent heat bodies which have a
tailored overall behavior in terms of the important
properties. For example, in a latent heat body the
method according to the invention allows the hardness
to be continuously adjusted. By way of example, to
produce a latent heat body from carrier material,
latent heat storage material and embedding material,
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the procedure may be such that small, relatively hard
balls of paraffin-impregnated diatomaceous earth are
worked into rubber-soft silicone which crosslinks at
room temperature, as embedding material, so that all in
all a flexible overall structure is obtained. As
another extreme, it is possible, for example, for
paraffin-containing, soft PAP fibers, i.e. wood fibers
with a high sucking capacity for latent heat storage
material, to be worked into concrete as embedding
material, resulting in a storage body which is overall
as hard as concrete. The production method described in
the different variants also proves advantageous for use
in particular because on the one hand practically any
desired shaping of the latent heat body is possible
prior to the solidification of the embedding material
and/or the matrix material, on account of the good flow
and/or kneading properties, and on the other hand the
selected shape is retained, after the solidification of
embedding and/or matrix material, even when the latent
heat storage material is liquefied as a result of heat
being supplied when the latent heat body is in use. In
this case, when using the method it is generally
preferred for the carrier material which is impregnated
with latent heat storage material to be enclosed
completely or on all sides by the embedding material.
It is correspondingly preferred that, when using a
matrix material, the conglomerates are enclosed therein
completely or on all sides. In addition, during first
initialization (initial heating) of the latent heat
body, paraffin residues on the outside can be melted
down and contribute to sealing of the embedding
material or the matrix material.
Furthermore, the method described with reference to the
preceding claims 29 to 39, for producing a latent heat
body, can also be refined in such a manner that the
carrier material which has been impregnated with latent
heat storage material is surrounded by an embedding
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material. In a manner analogous to the foregoing
constructions, in this case the carrier material which
has been impregnated with latent heat storage material
can be comminuted to form latent heat part-bodies, a
latent heat part-body containing a carrier material
part-body and latent heat storage material held therein
as well as, if appropriate, air volumes. The latent
heat part-bodies obtained can then together be
surrounded by an embedding material. Starting from the
method referred to here as well, it is possible to
produce a latent heat body simply by the embedding of
carrier material impregnated with latent heat storage
material in the embedding material in combination with
a desired shaping and subsequent solidification of the
embedding material. However, this method can also be
widened to the extent that, as explained above,
initially conglomerates in the sense of the present
patent application are produced from latent heat part-
bodies and the embedding material, and these
conglomerates are surrounded with a matrix material in
a subsequent method step, with the result that finally
the latent heat body is obtained. In this respect, for
further details reference is made to the above
constructions. An advantage of the proposed method
using embedding material and, if appropriate, matrix
material is in particular also that with this method
latent heat bodies can be produced without static
losses and without emulsifiers, without any problems.
The invention is explained in further detail below with
reference to appended drawings which, however, only
represent exemplary embodiments. In the drawings:
Fig. 1 shows a perspective view of a slab-like
construction element with integrated latent
heat body;
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Fig. 2 shows an excerpt enlargement of the latent
heat body in accordance with Fig. 1, with a
first carrier material;
Fig. 3 shows an excerpt enlargement of the latent
heat body based on Fig. 1, with a second
carrier material;
Fig. 4 shows a perspective view, cut open, of an
electric floor heating system with latent
heat bodies integrated therein;
Fig. 5 shows an excerpt enlargement of a latent heat
body in accordance with Fig. 4 formed from
latent heat part-bodies;
Fig. 6 shows a perspective view of a warming plate
for food in a first embodiment;
Fig. 7 shows a sectional view of a warming plate for
food in accordance with Fig. 6;
Fig. 8 shows a perspective view of a warming plate
for food in a second embodiment;
Fig. 9 shows a sectional view of a warming plate in
accordance with Fig. 8;
Fig. 10 shows a horizontal section through a
transport container with latent heat bodies
integrated therein;
Fig. 11 shows a perspective view of a latent heat
body according to the invention with
embedding material;
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Fig. 12 shows an enlarged partial section of the
latent heat body in accordance with Fig. 11,
along section line XII-XII;
Fig. 13 shows a partial section of a latent heat body
with embedding material and matrix material;
Fig. 14 shows a latent heat body with embedding
material in the form of a sole of a shoe;
Fig. 15 shows an enlarged partial section of the
latent heat body in accordance with Fig. 14
along section line XV-XV.
A slab-like construction element l, which is
substantially formed from a latent heat body 2
according to the invention, which in this case is
likewise in slab form, is illustrated and described,
initially with reference to Fig. 1. In detail, the
latent heat body 2 illustrated is a gypsum slab which
has been impregnated with latent heat storage material.
On a first surface, which extends in the slab plane,
the latent heat body 2 is provided with a covering 3
made from a sheet material, in the present case from
paper. In the installed condition of the construction
element 1, that surface of the latent heat body which
is provided with the covering 3 faces toward a room
which the' construction element 1 is used to delimit or
line. The opposite surface of the latent heat body 2
bears a weather protection 4, which likewise covers the
entire surface and is likewise produced from a sheet
material. The respective connection between the latent
heat body 2 and the covering 3 or the weather
protection 4 is achieved in a conventional way using an
adhesive introduced into the respective contact plane.
As an alternative or in combination, it is possible for
the covering 3 and the weather protection 4 to be fixed
to the latent heat body 1 by suitable joining means,
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such as for example staples, rivets or the like, and
for the covering 3 and/or the weather protection 4 to
be produced from other expedient materials, for example
from metal foil.
Fig. 2 shows an excerpt enlargement of the latent heat
body 2 from Fig. 1. According to this figure, the
latent heat body 2 comprises a carrier material 5,
which in the embodiment shown consists of a mineral
substance with an open capillary pore structure, and in
the specific embodiment consists of a gypsum material,
and is formed as a cohesive structure. Inside the
carrier material 5 there are capillary holding spaces 6
for latent heat storage material 7, which in the
example of Fig. 2 are formed by the open capillary pore
structure 8 of the gypsum material or are caused by
this structure. It can be seen from the highly
simplified and therefore only diagrammatic illustration
that the open capillary pore structure 8 has channels 9
with widenings 10 which together extend in the manner
of a labyrinth through the carrier material 5. Both the
channels 9 and the widenings 10 are dimensioned in such
a way that they exert a capillary action on liquefied
latent heat storage material and to this extent
represent capillary holding spaces 6 for the latent
heat storage material 7. The result of this is that
previously liquefied latent heat storage material,
during the production of the latent heat body 2, is
taken up from the adjoining environment, by the sucking
action, initially by holding spaces 6 which are close
to the surface and, from there, as a result of the
sucking action of adjacent holding spaces 6, passes
progressively into the interior of. the latent heat body
2, a desired quantity of latent heat storage material 7
continuing to flow into the holding spaces 6 which are
close to the edge, on account of their connections to
the environment. To this extent, Fig. 2 describes an
equilibrium state, in which the latent heat storage
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material 7 is present distributed uniformly over the
capillary holding spaces 6. In this case, the
distribution of the holding spaces 6 illustrated in one
plane also describes their qualitative distribution in
the further spatial directions. As indicated by the
respective area relationships, the proportion by mass
of the latent heat storage material 7, based on the
total mass of the latent heat body 2, in the example
described in Fig. 2 is thus approximately 250. It is
shown in further detail that the holding spaces 6 are
not completely filled with latent heat storage material
7, but rather residual air volumes 11 remain therein
which, in the example shown, are likewise uniformly
distributed. The residual air volumes 11 are
dimensioned in such a way that they absorb a
temperature-dependent change in volume of the latent
heat storage material 7 in the capillary holding spaces
6 of at most l00 of the latent heat storage material
volume. In Fig. 1, the channels 9 are only
diagrammatically indicated by simple lines.
Based on Fig. 1, Fig. 3 shows an excerpt enlargement of
a latent heat body 2', which differs from the latent
heat body 2 shown in Fig. 2 only through fiber elements
12 which are additionally present in the carrier
material 5. To this extent, corresponding constituents
of the latent heat bodies 2, 2' in Figs. 2 and 3 are
labeled with identical reference symbols. It can been
inferred from Fig. 3, which is likewise diagrammatic,
that the fiber elements 12 are of elongate and
irregular form and, with an irregular spatial
orientation, are disposed distributed approximately
uniformly inside the carrier material 5. Furthermore,
it becomes clear that in Fig. 3 the capillary holding
spaces 6 are not exclusively formed by the open
capillary pore structure 8 of the mineral gypsum
material, but rather the fiber elements 12 are in part
a constituent of the edge of the channels 9 and the
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widenings 10. Furthermore, there is the possibility -
not shown in the drawing in Fig. 3 - that in addition
capillary holding spaces 6 are completely bordered by
fiber elements 12.
In a perspective partial view, partially cut open, Fig.
4 shows an electric floor heating system 13 which is
disposed on a bare floor 14 made from concrete and
which has an upper covering 15 made from a material
which is customary for this purpose, for example from
dry screed and a floor covering which may have been
laid above it. Between the bare floor 14 and the
covering 15, heating registers 16 are provided, which
are diagrammatically illustrated and in the present
case are electric heating registers in a construction
form which is conventional for this purpose. Firstly, a
slab-like latent heat body 17, which in terms of its
constituents and its structural internal disposition
and distribution corresponds to the structure
represented in Fig. 2 in an excerpt enlargement, is
disposed between the bare floor 14 and the heating
register 16. Moving away from the exemplary embodiment
shown in Fig. 4, it is also possible for a thermal
insulation layer, for example a layer of Styropor, to
be provided immediately above the bare floor 14. In the
arrangement shown in Fig. 4, a first layer 18 with a
latent heat body 20 formed from granular latent heat
part-bodies 19 is situated between the slab-like latent
heat body 17 and the heating register 16. The first
layer 18 is to this extent a bed of latent heat part-
bodies 19 which are supported against one another, are
present in granule form and together form the latent
heat body 20.
As emerges in further detail from Fig. 5, an individual
latent heat part-body 19 contains a carrier material
part-body 21 and the latent heat storage material 7'
which is present in the capillary holding spaces 6
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contained therein, as well as the residual air volume
11 which is likewise contained therein. It follows from
this that a latent heat part-body 19, in its interior,
forms a cohesive structure with an open capillary pore
structure 8, while the latent heat body 20 as a whole
does not have a correspondingly cohesive structure.
Rather, in its interior it has spaces 22 between the
latent heat part-bodies 19, which spaces, depending on
the shape and size, may likewise exert a capillary
sucking action on the liquefied latent heat storage
material. Although this is not illustrated in the
drawing in Fig. 5, it is thus possible for latent heat
storage material 7, in an equilibrium state, also to be
situated in the spaces 22 and thus to make an
additional contribution to holding the latent heat
part-bodies 19 together. In the exemplary embodiment
shown in Figures 4 and 5, it is provided that the
latent heat storage material 7 held in the holding
spaces 6 of the latent heat part-bodies 19 has a phase
transition temperature of 52°C.
Furthermore, a second layer 23 with a latent heat body
formed from latent heat part-bodies 24 is disposed
between the heating register 16 and the covering 15.
25 The second layer 23 differs from the first layer 18
only through the nature of the latent heat storage
material 7" held in the respective capillary holding
spaces 6. While a latent heat storage material 7' with
a phase transition temperature of 52°C is held in the
first layer 18, as stated, a different latent heat
storage material 7" with a different phase transition
temperature, which in the present case is 42°C and is
therefore lower, is held in the second layer 23. In
principle, in this case it is also possible to provide
other phase transition temperatures.
In a perspective view, Fig. 6 shows a first embodiment
of a warming plate 26 for foodstuffs, in particular for
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rice. The warming plate 26 has a plate base body 27
with two receptacles 28 for foodstuffs 29 formed
thereon. In this case, it is provided that the plate
base body 27 contains a latent heat body 30 according
to the invention. In the example shown, the plate base
body 27 even consists entirely of the latent heat body
30, which is of a corresponding shape.
As indicated in the associated sectional view in Fig. 7
by the diagrammatic representation of the plate base
body 27, the internal structure of the latent heat body
30 corresponds to the structure diagrammatically
illustrated in Fig. 2. To this extent, the latent heat
body 30 also has a carrier material 5 made from a
gypsum material and capillary holding spaces 6
contained therein. In detail, these holding spaces are
channels 9 and widening 10, which together form an open
capillary pore structure 8. In connection with the
warming plate 26 as well, it is proposed that the
latent heat body 30 contains a proportion by mass of
approximately 25% latent heat storage material, based
on the total mass of the latent heat body 30, and that
residual air volumes 11, which are distributed
uniformly over the capillary holding spaces 6, absorb
temperature-dependent changes in volume of the latent
heat storage material 7 of at most 100 of the latent
heat storage material volume. With regard to the
structural configuration, it is proposed that the two
receptacles 28 each have a recess 32 which is
integrated into the top side 31 of the plate base body
27. The use of a warming plate 26 of this type may take
place in such a manner that it is initially preheated,
in an oven which is not shown in the drawing, to a
temperature which is above the phase transition
temperature of the latent heat storage material 7,
uniform heating through the plate base body 27 being
desirable with a view to optimal utilization of the
heat storage capacity. After the heating operation has
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ended, the warming plate 26 can be taken out of the
oven and a container, for example - as shown in Figures
6 and 7 - a pan 33, in the interior of which are
situated foodstuffs 29 which are to be kept warm and
are not shown in more detail, can be introduced into
the receptacles 28. Provided that or as soon as the pan
33 has a lower outside temperature than the surface of
the warming plate 26, heat transfer takes place from
the warming plate 26 to the pan 33 and, from there, to
the foodstuffs 29 contained therein, in the example
shown in Figures 6 and 7 specifically rice, which is
not shown in the drawing. As can be seen clearly in
particular from Fig. 7, the recesses 28, in terms of
their dimensions, are adapted to the shape of the pan
33 in such a manner that there is direct mutual contact
both at the bottom 34 and at the side walls 35.
Consequently, large-area and virtually unimpeded heat
transfer can take place preferably through thermal
conduction. To make it easier to insert the pan 33 into
a recess 28, an encircling rounded-off portion 36 in
terms of the cross section is provided along the upper
edge of the recesses 28. Since in accordance with the
exemplary embodiment shown in Figures 6 and 7, the
foodstuffs are situated in the interior of a separate
pan 33 and are therefore only brought into indirect
contact with the warming plate 26, the warming plate
can also be of particularly simple form including from
hygiene points of view. In particular, it is possible
to dispense altogether with an outer sheath, since, on
account of the inventive structure of the latent heat
body 30, there is also no risk of the latent heat
storage material sweating out, at least when the phase
transition temperature of the latent heat storage
material 7 is exceeded by from 30 to 40°K.
Figures 8 and 9 relate to a second embodiment of a
warming plate 37 for foodstuffs 29, in particular for
rice. The warming plate 37 has a plate base body 38
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which contains a latent heat body 39. The latent heat
body 39, in terms of its constituents and its internal
structure, does not differ from the latent heat body 30
illustrated in Figures 6 and 7. However, there are
differences in terms of the external shape and in that
the latent heat body 39 is enclosed by a sheath 40
which is impermeable to latent heat storage material 7
and in the specific example is formed from a metal foil
with good thermal conductivity. In detail, the sheath
40 has a bottom part 41 and a top part 42, which in the
region of a common encircling overlap 43 are joined to
one another by a layer of adhesive 44. The substantial
difference compared to the first embodiment of a
warming plate shown in Figures 6 and 7 therefore
consists in the fact that the foodstuffs 29, or the
rice, after the warming plate 37 has been heated in an
oven, are introduced directly into the receptacles 28
integrated into the top side 31, so that there is no
need for an additional container. The sheath 40 on the
one hand separates the foodstuffs 29 from the latent
heat body 39 and on the other hand allows easy cleaning
of the warming plate 37 without the risk of damage.
In a horizontal section, Fig. 10 shows a transport
container 45 with an outer housing 46 and an inner
housing 47 which is held therein, spaced apart by a
space. The outer housing 46 is additionally lined with
a thermal insulation 48, in the present case with a
layer of Styropor. In this case, it is provided that
latent heat bodies 49, 50 are disposed in the remaining
space. In the example shown, the latent heat bodies 40,
50 are each of plate-like form, the plate plane
extending perpendicular to the plane of the drawing. In
the specific example, four pairs of in each case one
latent heat body 49 and one latent heat body 50, which
are in contact with one another in a surface-parallel
manner, are formed, the pairs in the space between the
inner housing 47 and the outer housing 46 or the
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thermal insulation 48 being disposed in offset manner
with respect to one another. The latent heat bodies 49
each adjoin the inner housing 47, while the latent heat
bodies 50 each face the outer housing 46. Furthermore,
it is provided that respectively adjacent end faces 51,
52 of the latent heat bodies 49, 50 bear against
surface regions 53 of an adjacent latent heat body 49
which project beyond the inner housing 47, so that
there are no continuous cavities between the pairs of
latent heat bodies. In the exemplary embodiment shown,
the latent heat bodies 49, 50 have in principle the
same constituents and the same internal structure as
the latent heat body 2 illustrated in Fig. 2.
Differences may exist only in terms of the phase
transition temperatures of the respective latent heat
storage materials 54, 55, so that an optimum storage
action can be established as a function of the ambient
temperature of the outer housing 46 and the desired
temperature in the interior 56 of the inner housing 47,
by means of a multistage store. Furthermore, the
transport container 45 has a base (not shown) and a lid
which can pivot, for example by means of hinges, a
composite structure comprising a thermal insulation and
latent heat bodies expediently also being provided in
the base and lid regions. The transport container 45
illustrated is used to transport a material 57 which is
held in the interior 56 and is to maintain a
temperature which is as constant as possible during
transport. If the temperature of the material 57 is to
be above the ambient temperature, the latent heat
bodies 49, 50 may be heated in an oven prior to
transport and then inserted into the space between the
outer and inner housing. By contrast, if the transport
temperature is to be below the ambient temperature, the
latent heat bodies 49, 50 can be correspondingly cooled
prior to transport and then inserted into the transport
container. The transport container 45 shown in Fig. 10
can therefore advantageously be used for different
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purposes, latent heat bodies 49, 50 in which latent
heat storage material 54, 55 with phase transition
temperatures which have been specifically adapted to
the actual transport conditions is held, being selected
in each case.
In addition, it is pointed out that the latent heat
bodies described in connection with Fig. 1 to 10 may,
as an alternative to or in combination with the
features described in the specific case, also have one
or more of the further features which have been
explained in the general part of the description.
In Fig. 11, there is shown a perspective view of a
latent heat body 58 according to the invention, in
which a multiplicity of latent heat part-bodies 59,
which are initially illustrated in simplified form, are
surrounded by a common embedding material 60. As can be
seen in further detail from the enlarged sectional view
in Fig. 12, each of the latent heat part-bodies 59 has
a carrier material part-body 61, which in the example
shown is a granular grain of diatomaceous earth. The
carrier material part-body 61 is of an order of
magnitude at which a multiplicity of capillary holding
spaces 62 are situated in its interior; in practice,
the number of capillary holding spaces in a carrier
material part-body may be considerably higher than can
be shown in the greatly simplified illustration. This
correspondingly applies to the size of the individual
capillary holding spaces 62, which in reality may be
much smaller than the size illustrated in Fig. 12. In
further detail, it can be seen that latent heat storage
material 63 is held in each case inside individual
capillary holding spaces 62, while maintaining residual
air volumes 64. In the exemplary embodiment shown, the
capillary holding spaces 62 inside the carrier material
part-bodies 61 form a labyrinth-like structure in which
the paraffin-based latent heat storage material 63 is
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held. The individual latent heat part-bodies 59
together are surrounded by the embedding material 60,
which in the example shown is concrete. As a result of
the embedding material 60, a permanent cohesion is
produced between the carrier material part-bodies, and
this is retained even when the latent heat storage
material is liquefied. The plate form of the latent
heat body 58 which is expressed in Figure 11, during
production, was achieved by the fact that the mix
formed from the latent heat part-bodies 59 and the
embedding material 60, in an overall state in which it
still flowed freely, i.e. before the concrete set, was
poured into a corresponding mold. It can also be seen
from Fig. 12 that the proportion of the embedding
material 60 in the total mass of the latent heat body
58 is approximately 50%.
In Fig. 13, in a partial section there is a description
of a latent heat body 65 which has been modified
compared to Figures 11 and 12'to the extent that the
individual latent heat part-bodies 59 therein are
initially surrounded, in each case in smaller numbers,
by an embedding material 66, in the example illustrated
by silicone. This predominantly leads to the formation
of conglomerates 67 which each comprise a plurality of
latent heat part-bodies 59 which together are
surrounded by the embedding material 66. In the example
shown, as a result of the use of silicone as embedding
material 66, after crosslinking thereof, a permanent
and, within certain limits, resilient or elastic
cohesion between the latent heat part-bodies 59 of a
conglomerate 67 is achieved in the use state. It is
obvious that in practice the number of latent heat
part-bodies 59 per conglomerate 67 may vary
considerably and in particular may also considerably
exceed the numbers shown in the simplified
illustration. However, as is likewise shown, it is also
possible for individual latent heat part-bodies on
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their own to be surrounded by the embedding material
66. It is also shown in Fig. 13 that the conglomerates
67 together are surrounded by a matrix material 68,
which in the exemplary embodiment is concrete. The
matrix material 68 correspondingly produces cohesion
between the conglomerates 67, so that the latent heat
body 56 shown in Fig. 13 externally may not differ or
may only differ unsubstantially from the latent heat
body 58 shown in Figures 11 and 12.
A further exemplary embodiment of a latent heat body 69
according to the invention, in the form of a sole of a
shoe, is illustrated in Fig. 14. Using the reference
symbols which have already been used in connection with
Figures 11 and 12, the latent heat body 69 has an
embedding material 60 which, however, in the example
described here is silicone. A multiplicity of latent
heat part-bodies 59 are surrounded by the embedding
material 60, the proportion by mass of the silicone in
the total mass of the latent heat body 69 being
approximately 500. The silicone used as embedding
material 60 provides a permanent cohesion between the
latent heat part-bodies 59, the latent heat body 69
overall having a high resilience and therefore easy
deformability and good comfort properties in use.
As emerges in connection with the enlarged partial
section of the latent heat body 69 shown in Figure 15,
the latent heat part-bodies 59 contained therein are
shreds of cardboard with paraffin-based latent heat
storage material 63 held in capillary holding spaces 62
therein. It can also be seen that a residual air volume
64 is also formed in the capillary holding spaces 62.
The carrier material part-body, i.e. the cardboard
shred, contained in the latent heat part-body 59 in
accordance with Fig. 14 has a multiplicity of fibers
70, which are illustrated in simplified form, of wood
or cellulose which are held together by a binder which
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is customary in the production of cardboard. Moreover,
capillary holding spaces 62, in which the paraffin-
based latent heat storage material 63 and the residual
air volumes 64 are held, are formed between the fibers
70 in the interior of the carrier material part-body 61
in the example of the cardboard shred. Although this
cannot be seen from the illustration, the capillary
holding spaces may preferably be connected to one
another. The cardboard shreds, which in the example
illustrated are elongate, may be formed by prior
comminution of cardboard, for example by tearing or
cutting, while other geometries, for example round
platelets approximately in the shape of a relatively
small coin, can be used instead of the elongate shape.
On the other hand, the carrier material part-bodies may
also have a filament-like form and may be slightly
thicker than hairs. It is pertinent that the carrier
material is only comminuted sufficiently far or only
has a sufficient dimension for the capillary holding
spaces 62 to be retained therein, so that a good
suction capacity of the carrier material with regard to
the latent heat storage material 63 is ensured.
All the features disclosed are pertinent to the
invention. The content of the disclosure of the
associated/appended priority documents (copy of the
prior application) and the contents of the documents
PCT/EP 98/01956, DE 198 36 048.7, DE-A 43 07 065 are
hereby also fully incorporated into the disclosure of
the present application, partly for the purpose of
incorporating features of these documents in claims of
the present application.
