U.S. patent application number 12/522924 was filed with the patent office on 2010-04-22 for vacuum insulation panel and method for the production thereof.
This patent application is currently assigned to The Wall AG. Invention is credited to Gerd Niemoller.
Application Number | 20100095622 12/522924 |
Document ID | / |
Family ID | 39597717 |
Filed Date | 2010-04-22 |
United States Patent
Application |
20100095622 |
Kind Code |
A1 |
Niemoller; Gerd |
April 22, 2010 |
VACUUM INSULATION PANEL AND METHOD FOR THE PRODUCTION THEREOF
Abstract
The present invention relates to a vacuum insulation panel (1)
having a core (5) having insulating hollow spaces and cover layers
(11) closing off the core (5) from the environment, the hollow
spaces of the core (5) being formed by two chambers (3) sealed off
from each other in a gas-tight fashion, extending together with the
walls (4) or intermediate walls thereof from one cover layer (11)
to the other cover layer (11) and being formed from the walls (4)
or intermediate walls and the cover layers (11). The present
invention further relates to a method for producing such a vacuum
insulation panel (1), wherein a) plates (7) are produced having the
shape and arrangement in cross section of walls (4) of the half
chamber (3) connecting to each other, but being substantially
longer than the height of the walls (4) of the chambers (3), then
b) a composite (9) then being produced, in that a further such
plate (7) is laid on a first such plate (7) such that the entire
chambers (3) are formed, c) the plates (7) are then connected to
each other, in a gas-tight and permanent fashion, at the contact
points (8) thereof, d) further plates (7) are then laid on the
uppermost plate (7) of the composite (9) according to step b) and
connected, in a gas-tight and permanent fashion, to the uppermost
plate (7) of the composite (9) according to step c), e) the
composite (9) is further cut transverse to the plates (7) into
chamber discs (17) having the desired thickness corresponding to
the intended chamber height, and f) the chamber discs (17) are
connected, in a gas-tight and permanent fashion, to the cover
layers (11) on the open sides of the chambers (3).
Inventors: |
Niemoller; Gerd;
(Widziensko, PL) |
Correspondence
Address: |
Fleit Gibbons Gutman Bongini & Bianco PL
21355 EAST DIXIE HIGHWAY, SUITE 115
MIAMI
FL
33180
US
|
Assignee: |
The Wall AG
Schaffhausen
CH
|
Family ID: |
39597717 |
Appl. No.: |
12/522924 |
Filed: |
March 13, 2008 |
PCT Filed: |
March 13, 2008 |
PCT NO: |
PCT/EP2008/002039 |
371 Date: |
October 29, 2009 |
Current U.S.
Class: |
52/407.5 ;
29/897.32; 52/794.1 |
Current CPC
Class: |
F16L 59/065 20130101;
Y02B 80/12 20130101; E04B 1/803 20130101; B32B 37/146 20130101;
Y02A 30/242 20180101; B32B 2309/68 20130101; B32B 27/04 20130101;
B32B 3/12 20130101; B32B 2307/304 20130101; Y02B 80/10 20130101;
Y10T 29/49629 20150115 |
Class at
Publication: |
52/407.5 ;
29/897.32; 52/794.1 |
International
Class: |
E04B 1/74 20060101
E04B001/74; B21D 47/00 20060101 B21D047/00; E04C 2/36 20060101
E04C002/36 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 13, 2007 |
DE |
20 2007 000 542.3 |
Jul 31, 2007 |
DE |
10 2007 035 851.4 |
Claims
1. Vacuum insulation panel with a core with insulating hollow
spaces and also cover layers closing the core in a tight fashion
relative to the surroundings, wherein the hollow spaces of the core
are formed by chambers, wherein these chambers are closed gas-tight
relative to each other and reach, together with their walls or
intermediate walls, from a cover layer to the other cover layer,
and are formed from the walls or intermediate walls and the cover
layers.
2. Vacuum insulation panel according to claim 1, wherein the walls
or intermediate walls of the chambers form a honeycomb
structure.
3. Vacuum insulation panel according to claim 2, wherein the
honeycomb structure is rectangular, hexagonal, or octagonal,
contains circular shapes, or is regular or irregular.
4. Vacuum insulation panel according to claim 1, wherein each cover
layer is made from a gas-tight material or is coated with a
gas-tight material.
5. Vacuum insulation panel according to claim 1, wherein each cover
layer contains a layer or plate made from, in particular,
reinforced epoxy, melamine, or phenolic resin or the like in direct
contact with the walls or intermediate walls of the chambers.
6. Vacuum insulation panel according to claim 5, wherein the
reinforcement of the cover layer contains fiberglass material,
kraft paper, sisal or the like.
7. Vacuum insulation panel according to claim 1, wherein each cover
layer has a protective layer on its side facing away from the walls
or intermediate walls of the chambers.
8. Vacuum insulation panel according to claim 7, wherein the
protective layer contains a reflective high-barrier film or an
aluminum foil or a high-barrier coating or aluminum coating or the
like.
9. Vacuum insulation panel according to claim 1, wherein each cover
layer has a thickness greater than approximately 0.5 mm,
advantageously greater than ca. 1 mm, and especially preferred
approximately 1 mm.
10. Vacuum insulation panel according to claim 1, wherein the walls
or intermediate walls of the chambers are made from a gas-tight
material or are coated with a gas-tight material.
11. Vacuum insulation panel according to claim 1, wherein the walls
or intermediate walls of the chambers contain paper or cellulose
and/or the walls or intermediate walls of the chambers have a
coating with melamine resin, phenolic resin, or a melamine
resin-phenolic resin derivative and/or the walls or intermediate
walls of the chambers contain kraft paper or hard paper, in
particular, with reinforcement.
12. Vacuum insulation panel according to claim 1, wherein the walls
or intermediate walls of the chambers contain a metallic foil or
are coated with a metallic layer.
13. Vacuum insulation panel according to claim 1, wherein the walls
or intermediate walls of the chambers exhibit, with respect to one
cubic meter, thermal conductivity of less than ca. 0.3 W/mK,
advantageously less than approximately 0.2 W/mK, and especially
preferred less than approximately 0.1 W/mK.
14. Vacuum insulation panel according to claim 1, wherein the walls
or intermediate walls of the chambers have a thickness of
approximately 0.5 mm.
15. Vacuum insulation panel according to claim 1, wherein a vacuum
of approximately 98% prevails in the chambers.
16. Vacuum insulation panel according to claim 1, wherein a
heat-insulating gas, for example, argon or another noble gas or a
corresponding gas mixture is contained in the chambers.
17. Vacuum insulation panel according to claim 1, wherein the core
is sealed with artificial resin or the like at its free edges
between the cover layers.
18. Method for the production of a vacuum insulation panel
according to claim 1, wherein a) first, plates are produced that
have, in cross section, the shape and arrangement of walls of
half-chambers connected to each other but are significantly longer
than the height of the walls of the chambers, b) then a composite
is produced in which, on a first such plate, another such plate is
placed so that whole chambers are formed, c) then the plates are
connected to each other in a permanent and gas-tight fashion at
their contact points, d) then additional plates are placed
according to step b) one after the other onto the uppermost plate
of the composite and are connected in a permanent and gas-tight
fashion to the uppermost plate of the composite according to step
c), e) then the composite is cut perpendicular to the plates into
chamber discs with the desired thickness corresponding to the
intended chamber height, and f) finally, the chamber discs are
connected in a permanent and gas-tight fashion to the cover layers
on the open sides of the chambers.
19. Method according to claim 18, wherein the cover layers are
connected to the corresponding chamber discs one after the other
and that the second cover layer is connected to the assembly made
from the chamber discs and the first cover layer at a low pressure,
in a vacuum, or in a gas atmosphere with a gas that is provided as
a filling for the chambers.
20. Method according to claim 18, wherein the cover layers are
simultaneously connected to the corresponding chamber discs and
that the cover layers are connected to the chamber discs at a low
pressure, in a vacuum, or in a gas atmosphere with a gas that is
provided as a filling for the chambers.
Description
[0001] The present invention relates to a vacuum insulation panel
according to the preamble of Claim 1 and also to a production
method for this panel.
[0002] Such vacuum insulation panels are known from practice. They
have very high thermal and acoustic insulation properties and are
therefore used, e.g., as insulation panels. The vacuum insulation
panels named above are made from a core made from an open porous
material, for example, a noncompressive foam and sealing cover
layers or outer skins.
[0003] The vacuum insulation panels named above have the
disadvantage, among others, that the vacuum is lost with only
slight damage to the outer skin. For example, if a hole penetrating
the cover layers is drilled into the panel, then the core draws in
air and the insulation effect is lost or significantly reduced.
Another disadvantage is that the vacuum insulation panels named
above cannot be subjected to finishing work, but instead must
already have, from the start of the production in the factory,
before the evacuation of the core, the shape in which they are then
installed or used in some other way. Later finishing work is not
possible without the loss or drastic reduction of the insulation
property. Furthermore, the mechanical load capacity of known vacuum
insulation panels is insufficient for many applications. These
vacuum insulation panels cannot be used as load-bearing elements,
but instead are used merely for insulation.
[0004] The present invention has the goal of creating a vacuum
insulation panel that can be subjected to finishing work and
realizes this goal with a vacuum insulation panel according to
Claim 1 and also a production method for a vacuum insulation panel
according to Claim 18.
[0005] Thus, according to the invention, a vacuum insulation panel
is created with a core with hollow spaces and also cover layers
closing the core in a tight fashion from the surroundings, wherein
the hollow spaces of the core are formed by chambers that are
closed in a tight fashion relative to each other and that reach,
together with their intermediate walls, from one cover layer to the
other cover layer.
[0006] Such a vacuum insulation panel according to the invention
has numerous advantages. It can be used both as a high insulation
panel that can be cut arbitrarily, even after the evacuation, and
that essentially maintains its function, even with a partially
damaged surface, and also as a static structural element from which
load-bearing walls could be built.
[0007] Advantageously, the walls or intermediate walls of the
chambers form a honeycomb structure. Here, it could be further
provided advantageously that the honeycomb structure is
rectangular, hexagonal, or octagonal, contains circular shapes, or
is regular or irregular.
[0008] Another preferred configuration is that each cover layer is
made from a gas-tight material or is coated with a gas-tight
material. Alternatively or additionally, it could be provided that
each cover layer contains a layer or plate made from, in
particular, reinforced epoxy, melamine, or phenolic resin or the
like in direct contact with the walls or intermediate walls of the
chambers, wherein, in a further preferable way, the reinforcement
of the cover layer contains fiberglass material, kraft paper, sisal
or the like.
[0009] Another advantageous configuration is that each cover layer
has, on its side facing away from the walls or intermediate walls
of the chambers, a protective layer, wherein, in particular, the
protective layer can contain a reflective high barrier film or an
aluminum foil or a high barrier coating or aluminum coating or the
like.
[0010] Advantageously, each cover layer has a thickness of greater
than approximately 0.5 mm, advantageously greater than ca. 1 mm,
and especially preferred approximately 1 mm.
[0011] Another preferred configuration is that the walls or
intermediate walls of the chambers are made from a gas-tight
material or are coated with a gas-tight material.
[0012] Furthermore, it could advantageously be provided that the
walls or intermediate walls of the chambers contain paper or
cellulose and/or that the walls or intermediate walls of the
chambers have a coating with melamine resin, phenolic resin, or a
melamine resin-phenolic resin derivative and/or that the walls or
intermediate walls of the chambers contain kraft paper or hard
paper, in particular, with reinforcement. Alternatively or
additionally, it is preferred that the walls or intermediate walls
of the chambers contain a metallic foil or are coated with a
metallic layer.
[0013] Another advantageous configuration consists of walls or
intermediate walls of the chambers exhibiting, with respect to one
cubic meter, heat conductivity of less than ca. 0.3 W/mK,
advantageously less than approximately 0.2 W/mK, and especially
preferred less than approximately 0.1 W/mK. Corresponding values
are also influenced by the selection of the material pairing.
[0014] Furthermore, the walls or intermediate walls of the chambers
could advantageously have a thickness of approximately 0.5 mm.
[0015] In the chambers, advantageously a vacuum of approximately
98% prevails, or a heat-insulating gas, such as argon or another
noble gas or a corresponding gas mixture, is contained in the
chambers.
[0016] In another advantageous configuration, it is provided that
the core is sealed with artificial resin or the like at its free
edges between the cover layers.
[0017] In one special configuration, the invention further relates
to a vacuum insulation panel with an evacuated core or a core
filled with an insulating gas, and the core has, on both sides,
cover layers made from a gas-tight material or coated with a
gas-tight material. Here, the core is made from a plurality of
individual vacuum chambers that are formed by walls or intermediate
walls, wherein these walls extend, for example, perpendicular to
the cover layers and are arranged, in particular, in a regular
pattern and are connected to the cover layers in a gas-tight
fashion and are made from a gas-tight material or are coated with a
gas-tight material. Here, the walls could form a honeycomb pattern
or else, in cross section, circular tubules, or could have other
geometries. The walls or intermediate walls of the vacuum chambers
or, in general, chambers, could be made, in particular, from
cellulose coated with a phenolic resin, wherein, alternatively, the
construction from a metallic foil or from a material coated with a
metal or another similarly acting material comes into
consideration. The walls or intermediate walls thus form a
plurality of individual vacuum chambers that are covered on both
sides with a cover layer and are thus closed. At least one of the
cover layers is formed, for example, under vacuum conditions, so
that the chambers are evacuated.
[0018] The vacuum insulation panel according to the invention could
be produced in a large surface-area or endless configuration and
then could be cut to the required size: through cutting, only the
insulation effect of the actually cut chambers is lost--which is
different than vacuum insulation panels known from
practice--because these chambers are each closed in a gas-tight
fashion relative to the adjacent chambers. For example, even if a
nail is driven into one of the cover layers, the insulation effect
of only the affected chamber is lost, but not that of the vacuum
insulation panel as a whole.
[0019] The walls, advantageously in a regular configuration, and
the sandwich construction made from the honeycomb structure between
the two cover layers impart high strength to the vacuum insulation
panel, especially also relative to forces introduced to the vacuum
insulation panel in the plane of the cover layers. The vacuum
insulation panel thus could be used as a structural element of a
structure and for other purposes. In principle, the chambers could
also be filled, for example, with an open-pore foam, as is known
from the state of the art, as a planar, continuous core material,
or also with a closed-pore foam.
[0020] The honeycomb body can absorb high mechanical loads, much
higher than can wood plates, in connection with the cover layers
and, indeed, the honeycomb core weighs, e.g., only 33-60
kg/m.sup.3, in particular, for example, only ca. 44 kg/m.sup.3.
[0021] It is noted again that, instead of the vacuum in the
chambers, heat-insulating gases could also be used. In particular,
the possibility is imagined to use, e.g., argon or other noble
gases for special applications.
[0022] A vacuum insulation panel according to the invention could
be used for the following uses (wherein these uses for the
construction of the vacuum insulation panel are also disclosed
simultaneously as inventive concepts belonging to the
invention):
[0023] Gates (any type, e.g., garage doors, industrial doors,
etc.),
[0024] Doors of any type,
[0025] Swimming pool insulation,
[0026] Coolers, refrigerators, freezers, refrigerated rooms,
refrigerated warehouses or cold storage buildings.
[0027] Hot-storage containers for keeping food warm (e.g., rolling
containers in airplanes, etc.),
[0028] Pipe insulation of any type,
[0029] Ship insulation, room container construction for ships,
etc.,
[0030] Container construction, in general, e.g., refrigerated
containers, sanitary containers, office containers, magazine
containers, mobile homes, etc.,
[0031] Floor coverings of any type, e.g., laminate flooring,
refrigerated warehouse floors with aluminum, ribbed visual
appearance, etc.,
[0032] Intermediate coverings, house coverings of any type,
[0033] House roof, warehouse roof (flat roof, etc.) with various
associated visual appearances,
[0034] Walls as structural elements (replacement for stone) and as
additional insulation worked into the stone (brick, concrete block,
sandstone, etc.),
[0035] Door, gate, and window frame insulation of any type,
[0036] Roller blind blocks of any type could be produced or at
least insulated with vacuum insulation panels,
[0037] Heating systems (the system could be insulated),
[0038] Mobile home construction,
[0039] Swimming building construction,
[0040] Prefabricated building construction of any type,
[0041] Truck trailer construction (refrigerated trailer
construction, etc.),
[0042] Prefabricated garage construction (e.g., automobile
automatically heats up the garage with the remaining exhaust
heat),
[0043] Passive warehouse and passive house construction of any
type,
[0044] Furniture industry, etc.,
[0045] Particle board replacement,
[0046] Sheetrock replacement,
[0047] In a transparent visual appearance, as a window pane
replacement or as a multi-wall replacement
[0048] Paving stone (ground covering of any type; does not transmit
the coldness of the ground)
[0049] High-rise rooms, high-rise containers, high-rise structural
elements, etc.,
[0050] Vehicle insulation for, e.g., battery insulation, etc.,
[0051] Solar collector plates that produce distilled water
[0052] for hot-water accumulators, etc.
[0053] Cover and wall insulation with the associated visual
appearance both in areas inside and also outside,
[0054] Frost-proof street layer (below the blacktop; no more risk
of sliding)
[0055] Radiation protection (e.g., from radio waves in house
construction)
[0056] in any areas where space savings or stability is
demanded
[0057] Other applications or uses of vacuum insulation panels
according to the invention lie in the field of sound suppression
and sound insulation.
[0058] In addition, the invention creates a production method for
such vacuum insulation panels. This method according to the
invention for the production of a vacuum insulation panel contains
the following steps:
[0059] a) plates are produced that have, in cross section, the
shape and arrangement of walls of half-chambers connected one next
to the other but are significantly longer than the height of the
walls of the chambers,
[0060] b) then a composite is produced in which, on a first such
plate, another such plate is placed so that whole chambers are
formed,
[0061] c) then the plates are connected to each other in a
permanent and gas-tight fashion at their contact points,
[0062] d) then additional plates are placed according to step b)
one after the other onto the uppermost plate of the composite and
are connected in a permanent and gas-tight fashion to the uppermost
plate of the composite according to step c),
[0063] e) then the composite is cut perpendicular to the plates
into chamber discs with the desired thickness corresponding to the
intended chamber height, and
[0064] f) finally, the chamber discs are connected on the open side
of the chambers in a permanent and gas-tight fashion to the cover
layers.
[0065] Advantageously, in the method it is further provided that
the cover layers are connected one after the other to the
corresponding honeycomb disk, and that the second cover layer is
connected to the assembly made from the chamber disk and the first
cover layer at a low pressure, in a vacuum, or in a gas atmosphere
with a gas that is provided as a filling for the chambers.
Alternatively, it could also be provided that the cover layers are
simultaneously connected to the corresponding honeycomb structure
and that the cover layers are connected to the chamber disk at a
low pressure, in a vacuum, or in a gas atmosphere with a gas that
is provided as a filling for the chambers.
[0066] In particular, the production of the honeycomb or, more
precisely, its walls, from paper coated with melamine resin subject
to pressure (30 bar) and heat (185.degree. C.) is advantageous and
preferred. This type of honeycomb production has many
advantages:
[0067] thin honeycomb walls measuring approximately 0.5 mm are
produced that can carry high loads;
[0068] high thermal load capacity;
[0069] low weight; economical production; ultra-fast wetting (for
example, in 6 s);
[0070] simple production;
[0071] favorable tool prices, and many others.
[0072] In addition, the process of honeycomb evacuation according
to the invention is very advantageous.
[0073] Below, a processing section is shown in a special, preferred
configuration:
[0074] 1. Preimpregnated paper is produced
[0075] 2. The paper is preheated in a heating station, so that it
becomes soft and can be deformed
[0076] 3. In a preform, a ram brings the paper into a mold so that,
in a side press, 30 honeycombs, or another desired or suitable
number, could be pressed at one time; preferably, each ram moves
one after the other into the paper, so that it could be redrawn
from one side
[0077] 4. In the side press, for 30 honeycombs, or another desired
or suitable number, the oblique parts are pressed simultaneously,
the base remains unlinked
[0078] 5. The honeycombs are fused in that half honeycombs are
placed one on top of the other with their not-yet-linked bases and
pressed together with a press, so that the honeycomb bases fuse
together and a complete honeycomb is produced; this can be
performed in a so-called honeycomb fusing device in which the
honeycomb bases are fused to each other.
[0079] The honeycomb block is produced from one side in that a half
honeycomb is fused onto the previous half honeycomb. This is
realized in that an anvil is lowered into the last honeycomb and a
fusing ram presses against the anvil from one side. In this way,
the two not-yet-linked honeycomb bases are fused to each other. If
the anvil is made from a rather delicate ram, it is moved downward
into a stabilization plate, so that the anvil is held on two sides.
In this way, e.g., 30 honeycomb bases are fused to each other
simultaneously.
[0080] From the present document, additional preferred and
advantageous configurations of the production method for vacuum
insulation panels according to the invention are produced. This
produces, in particular, additional configurations of this method
that are worthy of protection.
[0081] Additional preferred and/or advantageous configurations of
the invention and their individual aspects will become apparent
from the claims and their combinations, as well as from the present
application document.
[0082] The invention will be explained in greater detail below
using embodiments with reference to the drawing merely as an
example, in which
[0083] FIG. 1 shows, in a schematic perspective view, an embodiment
of a preproduction stage of a vacuum insulation panel,
[0084] FIG. 2 shows, in a schematic side or longitudinal section
view, in cutaway, a vacuum insulation panel according to the
embodiment of the preproduction stage in FIG. 1,
[0085] FIG. 3 shows, in a schematic view, a part of the production
process of the vacuum insulation panel from FIG. 2,
[0086] FIG. 4 shows, in a schematic view, a part of the production
process that is larger than the diagram of FIG. 3 for the vacuum
insulation panel from FIG. 2,
[0087] FIG. 5 shows, in a schematic top view, a part of a vacuum
insulation panel from FIG. 2 in a preproduction stage,
[0088] FIG. 6 shows, in a schematic perspective view, an embodiment
of another preproduction stage of a vacuum insulation panel,
[0089] FIG. 7 shows, in a schematic view, the penultimate process
of the production process for the vacuum insulation panel from FIG.
2,
[0090] FIG. 8 shows, in a schematic view, the last process of the
production process for the vacuum insulation panel from FIG. 2,
[0091] FIG. 9 shows, in a schematic section view, an alternative
construction of the layout of the core, and
[0092] FIG. 10 shows, in a schematic perspective view, the
alternative construction of the layout of the core according to
FIG. 9.
[0093] With reference to the embodiments and applications described
below and shown in the drawings, the invention will be explained in
more detail using examples, i.e., it is not limited to these
embodiments or applications or to the combinations of features
within these embodiments and applications. Features of the method
and device are also given analogously from descriptions of the
device or method.
[0094] Individual features that are specified and/or shown in
connection with an actual embodiment are not limited to this
embodiment or the combination with the other features of this
embodiment, but instead could be combined in the scope of technical
possibility with any other variants, even if these are not
specifically discussed in the present document.
[0095] The same reference symbols in the individual figures and
diagrams designate components that are identical or similar or that
act identically or similarly. With reference to the diagrams, those
features that are not provided with reference symbols are also
clear, independent of whether those features are described below or
not. On the other hand, features that are included in the present
description but are not visible or not shown in the drawing are
also easily understandable to someone skilled in the art.
[0096] In FIG. 1, a preproduction stage 2 is shown schematically
from an embodiment of a vacuum insulation panel 1 in a perspective
view for illustrating the shape and arrangement of chambers 3 and
also their walls 4 or intermediate walls. FIG. 2 shows
schematically, in a side view or a longitudinal section, the layout
of the vacuum insulation panel 1. The vacuum insulation panel 1
will be explained in greater detail below in connection with FIGS.
3-8, and in the course of an embodiment of a production method
together with the corresponding production steps.
[0097] The vacuum insulation panels 1 are made from a chamber core
5, the honeycomb that was understood for the present embodiment and
therefore could also be designated as a honeycomb core. A hexagonal
shape is used, wherein octagonal and other shapes, including
irregular shapes, are also possible. The chamber core 5 is formed
by the walls 4 and thus contains the chambers 3. Such constructions
and structures are very stable, require little material, and are
also very light.
[0098] For forming the chambers 3 in the form of half-chambers 6,
corresponding plates 7 are pressed and then adhered to each other
to form the whole chambers 3, as FIGS. 3-6 show, or alternatively
fused. In this way, closed individual systems are produced. The
produced plates could also be designated as half-chamber plates 7
and are placed one on top of the other in the arrangement shown in
FIG. 1 and adhered, for example, to form a rigid and gas-tight
connection at their contact points 8, wherein a new plate 7 is
preferably always placed on an existing composite 9 and then
adhered, before the next plate 7 is placed and adhered, etc. Such a
block or composite 9 is cut perpendicular to the chamber or
honeycomb openings 10, so that the height of the chambers 3 and
their walls 4 produces the height of the chamber or honeycomb core
5, as is shown in FIG. 6. In FIG. 6, dimensions are specified that
are to be understood, furthermore, only as examples.
[0099] The chamber openings 10 are closed on both sides with a
cover layer 11 by mounting the cover layers 11 in a sealed and
rigid fashion on the corresponding sides of the chamber core 5. In
this way, many small closed cells or chambers 3 are produced, and
the height of the chambers 3 together with the thickness of the
cover layers 11 produces the thickness of the vacuum insulation
panel 1. Advantageously, the two cover layers 11 are adhered to the
chamber core 5 one after the other in separate processing steps,
and the second cover layer 11 is adhered, in particular, in a ca.
98% vacuum. Instead of adhesion, other attachment types are
possible, such as fusing or direct connection to each other by
means of materials that are not yet cured or only partially cured
in the chamber core 5 and/or the cover layers 11. Preferably, the
material of the cover layers 11 contains a not-yet-cured resin, so
that the curing of the resin takes place in a vacuum, in each case
during the application and connection of the second cover layer 11,
so that this vacuum is automatically produced and maintained in the
individual chambers or honeycomb cells 4.
[0100] Preferably, the cover layers 11 are made from a reinforced
epoxy resin. As the flow chart-like diagrams of FIGS. 7 and 8 show,
each cover layer 11 is introduced wet in a single production step
into a mold and cures in a vacuum. In this way, the walls 4 of the
chambers 3 are pressed into the not-yet-linked cover layers 11, so
that during the curing of the resin of each cover layer 11, the
walls 4 of the chambers 3 are connected in an air-tight fashion to
this cover layer 11. Through this procedure, the advantage is
achieved that for the quasi-combined production and attachment of
the cover layers 11 on the core 5, the cover layers 11 are
connected in a rigid, nondetachable, and also gas-tight fashion to
the wall material of the core 5.
[0101] In this way, a sandwich material is produced with high
stiffness, low weight, and very little framework. The core 5 with
the walls 4 of the chambers 3, that is, without cover layers 11,
has, for special embodiments, a volume weight of ca. 60 kg/m.sup.3
and a framework ratio to one cubic meter of 1:17. This ratio,
however, could also lie in the range of 1:33. Such a low
framework/volume ratio benefits the insulating power.
[0102] For the cover layers 11, other materials could also be used,
such as a derivative made from melamine and phenolic resin, which
represents a very economical solution. Under certain circumstances,
such cover layers 11 are connected separately to the core 5 of the
vacuum insulation panel 1, for example, by means of adhesion. Other
plastics could also be used. In particular, the cover layers 11
could also contain reinforcement 12 made from glass matt, kraft
paper, sisal or similar materials. An especially preferred layer
thickness of the cover layers 11 lies at approximately 1 mm.
[0103] In another configuration, the cover layers 11 are provided
on their outsides, i.e., the sides facing away from the core 5,
with a protective foil 13, such as, in particular, an aluminum foil
14. Such a protective film 13 and, in particular, an aluminum foil
14, has the advantage that, during the production and connection of
a cover layer 11 to the chamber walls 4, the corresponding, mold in
which the connection step finally takes place is protected, in
particular, from resin material contained in the cover layers 11,
so that absolutely no undesired adhesion of such resin material to
the mold can take place. Furthermore, such protective foils or
layers 13 could form an effective diffusion barrier against the
penetration of air into the vacuum chambers 3. Even for the use of
an aluminum foil 14 or the like, an additional advantage is also
achieved in that this is used with its glossy surface as a
reflection barrier for IR radiation, wherein the insulation power
of the vacuum insulation panel 1 is also increased.
[0104] The heat transfer takes place in the conventional insulation
materials known from the practice by means of so-called framework
conduction, gas conduction, and radiation conduction. The gas
conduction is the largest portion, ca. 2/3 of the entire heat
conduction. In order to eliminate this portion, modern
heat-insulation materials are evacuated, wherein gas conduction is
eliminated at least to a large degree. The radiation conduction is
stopped by means of reflective surfaces that reflect IR
radiation.
[0105] Even in the vacuum insulation panels according to the
invention, the air is evacuated, wherein gas conduction is
eliminated. For the corresponding construction with the aluminum
foil 14 as protective foil 13, IR radiation is prevented by means
of the high-gloss surface. What is left is framework conduction
that is calculated from the heat conductivity of the base material
and its mass.
[0106] In the presently discussed embodiment, the core 5 of the
vacuum insulation panel 1 is made from so-called hard paper. Hard
paper has, according to the reinforcement material that is used,
0.1-0.2 W/mK with respect to one cubic meter. The core with the
chambers 2 weighs 30-60 kg/m.sup.3, depending on the size of the
chambers. From this the framework, portions are given with respect
to cubic meters, as was already explained above, with a ratio of,
for example, ca. 1:17 to approximately 1:33, wherein these are
advantageous values. The thermal conductivity of a hard paper used
as an example with the already discussed values of 0.1-0.2 W/mK
leads to the result of values for the framework conduction of the
vacuum insulation panels 1 of, for example, 0.0058-0.0117 W/mK up
to, e.g., 0.0029-0.0058 W/mK.
[0107] A significant aspect for vacuum insulation panels 1 is the
diffusion of air into evacuated hollow spaces. The vacuum
insulation panels 1 are subject to a constant gas pressure that
attempts to create a pressure balance between the atmosphere and
the vacuum prevailing in the chambers 3 of the vacuum insulation
panels 1.
[0108] Vacuum insulation panels known from practice are made from a
foam core, a protective fleece, and a plastic barrier foil, usually
coated with aluminum. Due to its small layer thickness, this
barrier foil represents only little protection against diffusion.
In vacuum insulation panels known from practice, it is attempted to
balance out this deficiency through special barrier foils. Another
disadvantage of the known vacuum insulation panels is that they are
made from only one vacuum chamber, because the foam core is
produced from an open-pore foam, and thus pressure equalization
acts simultaneously on the entire system.
[0109] The special construction of the vacuum insulation panels 1
according to the present invention here has very decisive
advantages, because the pressure is loaded, in general, only on the
outer chambers 3 or honeycombs lying at the edge 15 between the
cover layers 11. Because the individual chambers 3 are sealed from
each other, a pressure balance must first take place in these outer
chambers 3 and must then propagate successively inward. This
advantage is achieved in that the core 5 of the vacuum insulation
panels 1 according to the invention is made from many individual
chambers 4 in which air can penetrate only one after the other from
the edge 15 between the cover layers 11. In order to further stop
this effect, preferred configurations provide that the core 5 is
sealed tight, with respect to diffusion at its free edges 15
between the cover layers 11, with artificial resin, such as, for
example, artificial resin body filler or the like.
[0110] The air pressure also acts on all chambers 4 simultaneously
by means of the cover layers 11. Here, the vacuum insulation panels
1 according to corresponding special constructions are especially
protected, wherein cover layers 11 of these panels are not made, as
is otherwise typical, from a thin sensitive plastic foil, but
instead from an, in particular, ca. 1 mm-thick reinforced epoxy
resin layer 12 that could also be provided with an aluminum foil 14
as a protective layer 13, as FIG. 2 shows. As an alternative to the
aluminum foil 14, a high-barrier film could also be the protective
layer 13 or form a component thereof. Instead of the construction
as a film, the protective layer 13 could also be realized as a
coating.
[0111] Below, a few production processes or steps will be discussed
in greater detail, within the scope of which additional device
features of the vacuum insulation panel 1 will also be specified or
illustrated.
[0112] In a chamber press station K (see FIG. 4), the plates 7 are
pressed that form, in cross section, half-chambers 6 and from which
the core 5 is later assembled. The material of the walls 4 or
intermediate walls of the chambers 3 or, expressed differently, of
the core 5, is made in the shown embodiment from kraft paper that
is coated with a melamine-phenolic resin derivative. The resin
cures under a pressure of 30 bar and a temperature of 185.degree.
C. in ca. 6 s. The advantage of the resin is that the linking takes
place only as long as energy is supplied. Thus, the resin could be
dried without curing completely. The wall material is delivered
ready for further processing and is dry in contrast to other resin
systems, and undergoes a curing reaction only under pressure and
heat. The linking process is completed within ca. 6 s. Subsequent
outgassing no longer takes place. Another advantage of this
material is that it is economical and can be stored as a raw
material without problems for a long time.
[0113] The walls 4 of the chambers 3 are ca. 0.5 mm thick and have
dimensions of 10 mm, from which a material length of 49.6 mm for
each chamber 3 is given for the walls 4. These values are to be
understood as examples and could vary according to construction and
requirements.
[0114] In order to keep the required pressing force from becoming
too high in a press P being used, for example, five half-chambers 6
are pressed simultaneously in one plate 7. In order to eliminate
the need to stretch the wall material, the material is
advantageously preshaped. For example, the material is flexible at
60.degree. C. and can be deformed with little pressure, which is
why a heat emitter W is used at the beginning of the chamber press
station K. As an alternative to the heat emitter W, the pressing
tool could also be heated. Because the preshaping could furthermore
take place very quickly and requires little pressure, a simple
prepress VP with a pneumatic cylinder PZ could be used and driven.
From the prepress VP, a preplate 7' is obtained that is completed
to form the plate 7 in the subsequent pressing step. One example of
this process section is shown schematically in FIGS. 3 and 4.
Accordingly, the entire pressing process combines the heating of
the paper, the preshaping, and the actual pressing.
[0115] The plates 7 produced in this way, with the cross-sectional
shape of half-chambers 3, are fed to an automatic core or block
adhesion device (not shown) in which these plates 7 are bonded
evenly to form a block 16 that could also be designated as a
honeycomb block or chamber block. In FIG. 5 it is shown
schematically how two such plates 7, are shown only in section, are
placed one on top of the other, in order to be able to connect to
each other at their contact points 8 in a rigid and gas-tight
fashion while forming the chambers 3, wherein this connection could
be realized through adhesion or fusing or in some other suitable
way.
[0116] For example, the points coming into contact with each other
or contact points 8 of two plates 7 arranged one on top of the
other are provided with a fast-curing adhesive that is deposited,
for example, by an automatic device. In practice, the adhesive is
deposited on the individual plates 7 before they are brought into
contact with each other and thus are bonded to each other quickly
and with good effect. These steps are repeated until a sufficient
number of plates 7 are rigidly connected to each other to form a
block 16.
[0117] Instead of the adhesion of plates 7 into a block 16, the
latter could also be formed by fusing plates 7, for example, in a
press (not shown).
[0118] Such a block 16 that is to be seen, for example, with
example dimensions in FIG. 6, is then transported to a saw (not
shown). From the block 16, chamber discs 17 are then cut
perpendicular to the plates 7 according to the panel thickness
desired later, i.e., under consideration of the thickness of the
cover layers 11 still to be deposited. The chamber discs 17
correspond directly to the cores 5 of the vacuum insulation panels
1 produced in this way.
[0119] In the next production processing step, the chamber discs 17
are provided with the cover layers 11 and, for example, a vacuum is
generated in the chambers 3. As was already specified further
above, a filling of the chambers 3 with selected gas material would
also take place here. The process of depositing the first cover
layer 11 and also the second cover layer is shown schematically in
FIGS. 7 and 8; for details refer to these sequences.
[0120] According to FIG. 7, in step S1, the protective foil 13, for
example, the aluminum foil 14, is placed in a mold F. In step S2,
the reinforced resin layer 12 is placed on the protective foil 13.
On this layer, in step S3, a chamber disk 17 or the core 5 is
placed, whereupon the mold F is closed with a cover D and the air
is drawn out from the interior of the mold F closed with the cover
D (step S4). The cover D is loosely covered with a rubber blanket G
toward the inside of the mold F, so that the evacuation of the
inside of the mold F and an inflow of air between the cover D and
the rubber blanket G presses the latter against the free side of
the core 5 and thus this core onto the reinforced resin layer 12
that is here also simultaneously pressed onto the protective layer
13, as shown in step S5. Here, the core 5 is rigidly pressed into
the wet resin of the cover layer 11. This state is maintained until
the resin of the cover layer 11 is cured. In step S6, after this
curing, air can flow back into the inside of the mold F and, after
opening the cover D, the composite made from the core 5 with the
first cover layer 11 can be removed.
[0121] Then as shown in FIG. 8, the protective film 13, for
example, the aluminum foil 14, is placed in a mold F' in step S11.
In step S12, the reinforced resin layer 12 is placed on the
protective foil 13. On this layer, in step S13, the composite made
from the core 5 with the first cover layer 11 is placed, whereupon
the mold F' is closed with a cover D' and the air is drawn out from
the inside of the mold F' closed with the cover D' (step S14). The
cover D' is loosely covered with a rubber blanket G' toward the
inside of the mold F', so that the evacuation of the inside of the
mold F' and an inflow of air between the cover D' and the rubber
blanket G' presses the latter against the free side of the
composite made from the core 5 with the first cover layer 11 and
thus presses this composite onto the reinforced resin layer 12 that
is simultaneously also pressed onto the protective layer 13, as
shown in step S15. Here, the composite made from the core 5 with
the first cover layer 11 is pressed rigidly into the wet resin of
the second cover layer 11. This state is maintained until the resin
of the second cover layer 11 is cured. After this curing, in step
S16, air can flow back into the inside of the mold F' and, after
opening the cover D' the completed vacuum insulation panel 1 can be
removed from the mold F'. Then the vacuum insulation panel 1 could
be cut into any shape.
[0122] In FIGS. 9 and 10, an alternative embodiment is shown
schematically, in a section view and a perspective view,
respectively, for the construction of the chamber core 5 with a
design. In this design, semicircular chambers 3' and cross-shaped
chambers 3'' are produced with which a favorable combination is
achieved for low heat conduction via the walls 4 between the cover
layers 11. With respect to the diagram in FIGS. 9 and 10, for
producing the chamber core 5 for a vacuum insulation panel 1 as in
the previously described embodiments of the production process,
discs are cut (in the diagram of FIG. 10, even and parallel to the
surface of the sheet of the drawing) from a block-like
preproduction stage.
[0123] With respect to the construction of the design of the
chambers, other variants are also possible. Thus, hemispheres (not
shown) that are equal to each other could be arranged on one side
in a plane in the same orientation. A second layer of hemispheres
that are equal, in turn, to each other and to the hemispheres of
the first layer could then be arranged on top, so that a hemisphere
of the first layer and a hemisphere of the second layer contact at
exactly one point. The cover layers are attached to the open sides
of the hemispheres. Thermal conduction must take place and then can
take place only via the contact points of the hemispheres, which
means significantly less material. This version is not limited to
hemispheres, but instead functions with any coupling-like shape
that could also be correspondingly flat according to the small
thickness of the vacuum insulation panel 1, such as spherical
segments or segments of spherical bodies or other coupling-like
formations. Such designs could be produced, for example, through
injection molding, deep drawing, and other known techniques both in
preproduction stages, for example, individual first and second
layers, or as a complete core in a single process.
[0124] With respect to the material pairing for the material of the
core 5, all combinations are advantageous that result in an
optimization of the lowest possible heat conduction. These include
others in addition to the already-named material pairing consisting
of paper and a melamine/phenolic resin derivative. If the organic
material of paper or wood is replaced by an inorganic substance,
such as fiberglass matt material, then the heat conduction is
reduced. For the material of the core 5, a pure ceramic base
material is also conceivable, that is, a combination of several
materials is not absolutely necessary.
[0125] The invention is shown as an example with reference to the
embodiments in the description and in the drawing and is not
limited to, but instead includes, all variations, modifications,
substitutions, and combinations that someone skilled in the art
could take from the present document, in particular, in the scope
of the claims and the general statements in the introduction of
this description and also from the description of the embodiments,
and could combine with his technical knowledge and also with the
state of the art. In particular, all of the individual features and
construction possibilities of the invention and its embodiments
could be combined.
* * * * *