US20150226440A1

US20150226440A1 - Heat-conducting plate, especially for cooling or heating a building

Info

Publication number: US20150226440A1
Application number: US14/428,474
Authority: US
Inventors: Johann Lipinski; Thomas Vogel; Jochen Pfeiffer
Original assignee: Uponor Innovation AB
Current assignee: Uponor Innovation AB
Priority date: 2012-09-17
Filing date: 2013-09-16
Publication date: 2015-08-13
Also published as: DE202012103540U1; EP2751512A1; KR20150058364A; CA2881333A1; WO2014041173A1; JP2015531469A

Abstract

A heat-conducting plate, in particular for cooling or heating a building. The heat-conducting plate including at least one layer of expanded graphite and a pipe which is at least partially received in the layer. The pipe is designed as a multi-layer composite pipe.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a US National Stage of International Application No. PCT/EP2013/069164, filed on Sep. 16, 2013, which claims the priority of DE Application No. 20 2012 103540.5. filed on Sep. 17, 2012. The contents of each of the above-referenced applications is incorporated herein by reference in its entirety.

FIELD OF INVENTION

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.

BACKGROUND

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 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.

SUMMARY

It is an object of the invention to present a solution which avoids the aforementioned disadvantages.
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.
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.
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.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic cross section of a heat-conducting plate according to a first exemplary embodiment of the invention,

FIG. 2 shows a schematic cross section of a heat-conducting plate according to a second exemplary embodiment of the invention,

FIG. 3 shows a schematic cross section of a heat-conducting plate according to a third exemplary embodiment of the invention,

FIG. 4 shows a schematic plan view of a heat-conducting plate according to a fourth exemplary embodiment of the invention,

FIG. 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

FIG. 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.

DETAILED DESCRIPTION

FIG. 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.
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.
FIG. 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 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 FIG. 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.
FIG. 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 FIG. 2. In contrast to the configuration shown in FIG. 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.
FIG. 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 FIGS. 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.
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 FIG. 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 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 FIG. 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 FIG. 4 can be introduced into the layer 2.
FIG. 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.

LIST OF REFERENCE SIGNS

1 Heat-conducting plate
2 Layer
3 Multi-layer composite pipe
4 Surface
5 Plastic layer
6 Adhesion-promoting layer
7 Metal layer
8 Adhesion-promoting layer
9 Plastic layer
10 Pipe outer side
11 Bottom side
12 Mineral wool
13 Connection
14 Connection
15 Holding apparatus
16 Bend region
17 Recess
18 Layer
19 Arrow direction
20 Arrow direction
21 Hole

Claims

1. A heat-conducting plate 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, wherein the pipe is designed as a multi-layer composite pipe.

2. The heat-conducting plate according to claim 1, in which the multi-layer composite pipe has an inner plastic layer, an adhesion-promoting layer and an outer metal layer.

3. The heat-conducting plate according to claim 1, in which 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.

4. The heat-conducting plate according to claim 2, in which the inner plastic layer and/or the outer plastic layer are formed essentially from polyethylene (PE) and the metal layer is formed essentially from an aluminum material.

5. The heat-conducting plate according to one-of claim 1, in which at least one surface is perforated or has textures.

6. The heat-conducting plate according to claim 1, in which at least one surface has a layer of mineral wool.

7. The heat-conducting plate according to claim 1, in which provision is made of holding apparatuses for attachment to further heat-conducting plates or other elements, including wall and ceiling surfaces.

8. The heat-conducting plate according to claim 1, which is produced by pressing the expanded graphite with the inserted multi-layer composite pipe.

9. The heat-conducting plate according to claim 1, which is produced by pressing the multi-layer composite pipe into recesses in the layer.

10. The heat-conducting plate according to claim 1, which has a further layer of expanded graphite and is produced by pressing the two layers with the multi-layer composite pipe arranged therebetween.

11. The heat-conducting plate according to claim 1, which comprises additives, including synthetic resin.