Note: Descriptions are shown in the official language in which they were submitted.
CA 081333 2015--05
- 1 -
HEAT-CONDUCTING PLATE, ESPECIALLY FOR COOLING OR HEATING A
BUILDING
Description
Heat-conducting plate, especially for cooling or heating a
building
The present invention relates to a heat-conducting plate, in
particular for cooling or heating a building, comprising at
least one layer of expanded graphite and a pipe which is at
least partially received in the layer.
Heat-conducting plates of the type mentioned in the
introduction are known from the prior art. By way of example,
European patent EP 1 512 933 A2 describes heat-conducting
plates made of expanded graphite without binder with preferred
heat conduction parallel to the plate surface. Furthermore,
said document describes a method for producing the heat-
conducting plates. In this case, completely expanded graphite
is compacted under the directional action of a pressure, such
that layer planes of the graphite are preferably arranged
perpendicular to the action of the pressure, with individual
aggregates of the graphite hooking up with one another. It is
thereby possible to produce self-supporting heat-conducting
plates having a thickness, for example, of 8 to 50 mm.
Heat-conducting plates of this type are used, for example, as
wall, floor or ceiling elements for heating or cooling a room.
For this purpose, the heat-conducting plate can be used, for
example, in conjunction with heating systems which utilize a
fluid heat transfer medium. Pipes made of metal, for example
copper, or plastic are introduced into the heat-conducting
plates for the transportation of a fluid heat transfer medium,
for example water. The pipes in this respect are generally
CA 081333 2015--05
- 2 -
arranged in a helical or meandering manner. As an alternative,
the pipes can also be placed between two heat-conducting
plates, which are then pressed together.
When using plastic pipes, it proves to be a disadvantage that
restoring forces of the pipe arise during the production of the
heat-conducting plate, for example when the pipes are arranged
in a helical or meandering manner in a heat-conducting plate.
This is because the pipes arranged in the expanded graphite
readily undergo elastic deformation during the production as a
result of the action of pressure. These restoring forces can
lead to damage to the heat-conducting plate particularly in the
case of relatively thin heat-conducting plates. Furthermore, it
is possible that the plastic pipes may come loose and become
separated on account of these restoring forces if they are not
completely embedded in the heat-conducting plate. In addition,
the pressing of a plastic pipe into a heat-conducting plate or
the pressing together of two heat-conducting plates with a
plastic pipe arranged therebetween may cause damage to the
plastic pipe itself.
The use of copper pipes is very expensive and, on account of
the high dead weight, leads to heavy heat-conducting plates.
Furthermore, corrosive damage can arise on the copper pipe
under certain conditions. By way of example, the presence of
condensed water and at least one further metal, e.g. aluminum,
can form a galvanic cell on account of the different
electrochemical potentials of the metals, and this leads to
galvanic corrosion of the copper pipe. This can lead, for
example, to leaks or to undesirable discolorations of the
copper pipe.
It is an object of the invention to present a solution which
avoids the aforementioned disadvantages.
CA 02881333 2015-02-05
- 3 -
Said object is achieved according to the invention by a heat-
conducting plate, in particular for cooling or heating a
building, which comprises at least one layer of expanded
graphite and a pipe which is at least partially received in the
layer. The pipe which is at least partially received in the
layer is in this case designed as a multi-layer composite pipe.
The use of a multi-layer composite pipe prevents restoring
forces from arising during the production of the heat-
conducting plate, for example when the multi-layer composite
pipe is arranged in a helical or meandering manner. A multi-
layer composite pipe bent or shaped according to the desired
arrangement essentially does not alter its shape or its
position. If the multi-layer composite pipe should be bent or
deformed during the production process, it undergoes plastic
deformation and no high restoring forces arise. Damage to the
layer of the heat-conducting plate or separation from the layer
is therefore not possible. In contrast to a pure plastic pipe,
the multi-layer composite pipe has greater stability and
thereby contributes to the stability of the entire heat-
conducting plate. In contrast to copper pipes, multi-layer
composite pipes have a considerably lower weight and are not
susceptible to corrosion, in particular in the region of the
outer side of the pipe, in the presence of a second metal. In
addition, it is possible to reduce the production costs of a
heat-conducting plate according to the invention considerably
compared to a heat-conducting plate comprising copper pipes.
According to an advantageous configuration of the invention,
the multi-layer composite pipe has an inner plastic layer, an
adhesion-promoting layer and an outer metal layer. A multi-
layer composite pipe of this type is distinguished by its low
weight combined with good heat conduction.
,
I
CA 02881333 2015-02-05
- 4 -
According to a further advantageous configuration of the
invention, the multi-layer composite pipe has an inner plastic
layer, an adhesion-promoting layer, a metal layer, a further
adhesion-promoting layer and an outer plastic layer. A multi-
layer composite pipe of this type is distinguished by its high
stability and flexural rigidity.
According to a further advantageous configuration of the
invention, at least one surface of the heat-conducting plate is
perforated or has textures. When a heat-conducting plate of
this type is used in a building, for example, it is thereby
possible to improve the acoustic properties of the heat-
conducting plate, in particular the sound absorption.
According to a further advantageous configuration of the
invention, at least one surface of the heat-conducting plate
has a layer of mineral wool. It is thereby likewise possible to
improve the acoustic properties of the heat-conducting plate.
According to a further advantageous configuration of the
invention, the heat-conducting plate is provided with
apparatuses for attachment to further heat-conducting plates or
other elements, in particular wall and ceiling surfaces. A
heat-conducting plate can thereby be attached to a ceiling
surface of a room in a suspended manner, for example.
According to a further advantageous configuration of the
invention, the heat-conducting plate is produced by pressing
the expanded graphite with the inserted multi-layer composite
pipe.
According to a further advantageous configuration of the
invention, the heat-conducting plate is produced by pressing
the multi-layer composite pipe into recesses in the layer of
expanded graphite.
CA 081333 2015--05
- 5 -
According to a further advantageous configuration of the
invention, the heat-conducting plate has a further layer of
expanded graphite and is produced by pressing the two layers
with the multi-layer composite pipe arranged therebetween.
According to a further advantageous configuration of the
invention, the heat-conducting plate comprises additives, in
particular synthetic resin.
Further advantageous configurations of the invention are
disclosed in the following detailed description of exemplary
embodiments and also the dependent patent claims.
Hereinbelow, the invention will be described on the basis of
the exemplary embodiments with reference to the accompanying
figures. In the figures, identical components from different
exemplary embodiments are provided with identical reference
signs and are not described repeatedly.
In the figures:
Figure 1 shows a schematic cross section of a heat-conducting
plate according to a first exemplary embodiment of
the invention,
Figure 2 shows a schematic cross section of a heat-conducting
plate according to a second exemplary embodiment of
the invention,
Figure 3 shows a schematic cross section of a heat-conducting
plate according to a third exemplary embodiment of
the invention,
CA 081333 2015--05
- 6 -
Figure 4 shows a schematic plan view of a heat-conducting
plate according to a fourth exemplary embodiment of
the invention,
Figure 5 shows a schematic cross section of a heat-conducting
plate in the event that a multi-layer composite pipe
is pressed in, according to a fifth exemplary
embodiment of the invention, and
Figure 6 shows a schematic cross section of a heat-conducting
plate in the event that two layers and a multi-layer
composite pipe are pressed, according to a sixth
exemplary embodiment of the invention.
Figure 1 shows a schematic cross section of a heat-conducting
plate 1 according to a first exemplary embodiment of the
invention. The heat-conducting plate 1 has a layer 2 of
expanded graphite. Furthermore, the heat-conducting plate 1 has
a multi-layer composite pipe 3, which is introduced into the
layer 2 partially on a surface 4.
The multi-layer composite pipe 3 has an inner plastic layer 5,
for example of crosslinked polyethylene (PE-X). Alternatively,
the inner plastic layer 5 can also consist of a polyethylene
material for an increased temperature resistance (PE-RT).
Moreover, the multi-layer composite pipe 3 has an adhesion-
promoting layer 6. The adhesion-promoting layer 6 bonds the
inner plastic layer 5 to an outer metal layer 7. By way of
example, the outer metal layer 7 can be produced from an
aluminum material or an aluminum alloy.
A heat-carrying fluid, for example water, flows inside the
multi-layer composite pipe 3, in order to emit heat to the
layer 2 or in order to absorb heat from the layer 2.
CA 081333 2015--05
- 7 -
The heat-conducting plate 1 is produced by placing the multi-
layer composite pipe 3 into expanded graphite and subsequent
pressing. The action of directional pressure forms the layer 2
of expanded graphite, into which the multi-layer composite pipe
3 is at least partially embedded, such that there is a force-
fitting and/or form-fitting connection between the layer 2 and
the multi-layer composite pipe 3.
Alternatively, the heat-conducting plate 1 can comprise
additives, in particular synthetic resin, in order for example
to increase the stability of the heat-conducting plate 1. In
this case, the additives can be admixed to the expanded
graphite during the production of the layer 2 or can be
attached to the layer 2 or applied thereto subsequently, for
example as an additional layer.
The heat-conducting plate 1 is suitable, for example, for use
in a building for cooling or heating rooms. It is preferable
for the heat-conducting plate to be suspended on a ceiling of a
room. In this case, the heat-conducting plate 1 absorbs heat
from the ambient air which surrounds it via the layer 2, for
example, and emits this heat to the fluid inside the multi-
layer composite pipe 3 for cooling the room. Conversely,
thermal energy of the fluid is emitted via the multi-layer
composite pipe 3 to the layer 2, which in turn emits the heat
to the ambient air which surrounds it for heating the room, in
particular by radiation.
Figure 2 shows a schematic cross section of a heat-conducting
plate 1 according to a second exemplary embodiment of the
invention. The heat-conducting plate 1 has a multi-layer
composite pipe 3, which is formed by five layers. The multi-
layer composite pipe 3 has an inner plastic layer 5, an
adhesion-promoting layer 6, a metal layer 7, a second adhesion-
promoting layer 8 and a second, outer plastic layer 9. The
=
CA 081333 2015--05
- 8 -
multi-layer composite pipe 3 is arranged within the layer 2 in
such a manner that a pipe outer side 10 of the multi-layer
composite pipe 3 terminates flush with the surface 4 of the
layer 2.
The inner plastic layer 5 and also the second, outer plastic
layer 9 can consist, for example, of crosslinked polyethylene
(PE-X) or of a polyethylene material for an increased
temperature resistance (PE-RT). The metal layer 7 can be
produced from an aluminum material or an aluminum alloy.
Compared to the configuration shown in figure 1, the multi-
layer composite pipe 3 has a higher stability or rigidity
combined with a low dead weight.
The arrangement of the multi-layer composite pipe 3 flush with
the surface 4 ensures a good transfer of heat between the layer
2 and the multi-layer composite pipe 3. This is primarily
because the heat conduction within the layer 2 is better
parallel to the surface 4 than perpendicular to the surface 4
of the layer 2 on account of the fact that the layer 2 is
produced under directional pressure.
In an embodiment of the heat-conducting plate 1 which is not
shown, at least one outer side of the layer 2 may be perforated
or have textures. It is thereby possible for acoustic
properties of the heat-conducting plate 1 to be improved. By
way of example, depressions can be made on such an outer side
of the heat-conducting plate 1.
Figure 3 shows a schematic cross section of a heat-conducting
plate 1 according to a third exemplary embodiment of the
invention. Here, the heat-conducting plate 1 is configured in a
manner corresponding substantially to the second exemplary
embodiment shown in figure 2. In contrast to the configuration
CA 081333 2015--05
- 9 -
shown in figure 2, however, the multi-layer composite pipe 3 is
arranged within the layer 2 in such a manner that it is spaced
apart from a surface 4 and a bottom side 11 of the layer 2. In
addition, the heat-conducting plate 1 has a layer of mineral
wool 12 on the surface 4 of the layer 2. Moreover, holes 21, in
particular bores, are provided in the layer 2. It is thereby
possible in conjunction with the mineral wool 12 to achieve a
sound absorption effect, for example. By way of example, the
layer of mineral wool 12 can also be arranged on another outer
side or a plurality of outer sides of the layer 2.
Alternatively, however, it is also possible for other layers,
for example plastic layers or metal layers, to be attached to
one or more outer sides of the layer 2, in order for example to
protect the heat-conducting plate 1 against mechanical or other
environmental influences.
Figure 4 shows a schematic plan view of a heat-conducting plate
1 according to the invention with a multi-layer composite pipe
3 embedded therein. The heat-conducting plate 1 has a first
connection 13 and a second connection 14. The connection 13 and
the connection 14 are connected via a multi-layer composite
pipe 3 as per a configuration on the basis of figures 1 to 3.
Here, the multi-layer composite pipe 3 is arranged within the
layer 2 in a meandering manner. Moreover, the heat-conducting
plate 1 has two holding apparatuses 15 for attaching the heat-
conducting plate 1 to wall or ceiling surfaces. In addition,
the multi-layer composite pipe 3 has a plurality of bend
regions 16.
By way of example, the holding apparatuses 15 can have nails,
brackets, hooks or anchors, in order to attach the heat-
conducting plate 1 to a ceiling surface of a room.
CA 081333 2015--05
- 10 -
By way of example, essentially no restoring forces arise in the
bend regions 16 during the production of the heat-conducting
plate 1 by virtue of the use of the multi-layer composite pipe
3, since the multi-layer composite pipe 3 can be plastically
shaped beforehand by the metal layer 7.
The heat-conducting plate 1 is connected, for example, to a
heating system, with a fluid, for example water, entering into
the multi-layer composite pipe 3 via the connection 13. In
accordance with the arrangement of the multi-layer composite
pipe 3, the fluid is distributed over the surface area of the
layer 2. The fluid flows away again via the connection 14.
A heat-conducting plate 1 of this type is suitable in
particular for use in buildings for cooling or heating a room.
Heat-conducting plates of this type are preferably fastened to
ceilings of a room. It proves to be particularly advantageous
that the heat-conducting plate 1 has a considerably lower dead
weight compared to heat-conducting plates having copper pipes
on account of the low weight of the multi-layer composite pipe
3. It is thereby possible for heat-conducting plates of this
type to also be attached to ceilings of buildings with a
smaller load-bearing capacity, for example old buildings.
Moreover, it is possible to produce comparatively thin heat-
conducting plates, because the multi-layer composite pipe 3
contributes to the stability of the layer 2 of expanded
graphite above all on account of the metal layer 7.
The connections 13 and 14 of the heat-conducting plate 1 which
are shown in figure 4 can be arranged in a different manner on
the layer 2, for example lying opposite one another. In
addition, the multi-layer composite pipe 3 can also run
differently within the layer 2, for example in a helical
manner. Moreover, it is conceivable for a plurality of multi-
layer composite pipes 3 to be arranged within a layer 2, these
CA 081333 2015--05
- 11 -
being connected to a heating system, for example, via the
connections 13 and 14 and/or further connections.
What is shown in a fifth exemplary embodiment of the invention
as per figure 5 is a schematic cross section of a heat-
conducting plate 1 in the event that a multi-layer composite
pipe 3 is pressed in. The layer 2 which has already formed
under the action of pressure has a recess 17, this having been
made in a post-machining step, for example. The recess 17 is
matched to an external diameter and the arrangement or shape of
the multi-layer composite pipe 3 in such a manner that the
multi-layer composite pipe 3 can be pressed, pushed or placed
into the recess 17.
By way of example, the recess 17 can be configured in such a
manner that a multi-layer composite pipe 3 arranged in a
meandering manner as per the configuration shown in figure 4
can be introduced into the layer 2.
Figure 6 shows a schematic cross section of a heat-conducting
plate 1 to be pressed according to a sixth exemplary embodiment
of the invention. In addition to the layer 2, the heat-
conducting plate 1 has a second layer 18 of expanded graphite
which has already formed under the action of pressure. The
multi-layer composite pipe 3 is placed between the two layers 2
and 18. The heat-conducting plate 1 is produced by pressing the
two layers 2 and 18, for example under the action of pressure
as per the arrow directions 19 and 20. A force-fitting and/or
form-fitting connection is established between the two layers 2
and 18 and also the multi-layer composite pipe 3.
The features of a heat-conducting plate which have been
presented in the exemplary embodiments described can be
combined with one another in various ways in order to realize
the respectively mentioned advantages and/or functions.
CA 02881333 2015-02-05
- 12 -
List of reference signs
1 Heat-conducting plate
2 Layer
3 Multi-layer composite pipe
4 Surface
Plastic layer
6 Adhesion-promoting layer
7 Metal layer
8 Adhesion-promoting layer
9 Plastic layer
Pipe outer side
11 Bottom side
12 Mineral wool
13 Connection
14 Connection
Holding apparatus
16 Bend region
17 Recess
18 Layer
19 Arrow direction
Arrow direction
21 Hole
