Field of the Invention
[0001] The present invention relates to a spacer for forming a spacing between glass panes.
The spacer comprises a top part and a lower metal foil, wherein said top part has
an inner wall part with overlap surfaces at each end for connecting to said metal
foil, and wherein said metal foil has an outer wall part and two lateral sidewalls
extending from said outer wall part, and towards said top part. The present invention
further relates to a method of manufacturing a spacer and a window comprising glass
panes being mutually spaced by a spacer.
Background of the Invention
[0002] It is well known to provide spacers in order to define the spacing between the panes
of isolating glazings consisting of a plurality of parallel glass panes spaced by
an isolating cavity.
[0003] A plurality of such spacers made of different materials and of different shapes is
known in the art. Spacers made by roll forming of a metal foil are widely used in
the art and considered to be one of the preferred alternatives because of their stability
and their low gas diffusion properties.
[0004] Insulating Glass Units (IG units) having a plurality of glass panes are made by automatic
manufacturing machines. Spacers are automatically bent to the desired size and shape
and are arranged between two neighbouring glass panes. Spacers made of metal foils
can be easily bent and will remain in the bent position.
[0005] Furthermore, spacers made of metal foils have a high resistance against diffusion
of gases and moisture penetration. Within the space between the neighbouring glass
panes, there is arranged a gas, for instance argon having good isolating properties.
In order to avoid any loss of gas, the spacers delimiting the cavity need to be resistant
against diffusion of such gaseous elements.
[0006] However, known spacers which are exclusively made of metal such as aluminium and
galvanized steel have also some disadvantages. Due to a relatively high heat conductivity
of metal, spacers made of a metal foil still have a heat conductivity which under
certain circumstances may be too high.
[0007] In order to further reduce the heat conductivity, it has been suggested to use plastic
material for forming such spacers. Plastic material has, however, relatively high
gas diffusion as compared to metal. It thus has been suggested to provide a metal
foil over a plastic body. Such a spacer is e.g. shown in
EP 852 280.
[0008] A further problem of spacers made of plastic material is their instability during
the manufacturing process. In particular, a spacer bent to the desired frame shape
may be slightly deformed during assembly because of the resiliency of plastic material.
Misalignments of the spacer during manufacturing thus are possible. In order to avoid
this problem, it has been suggested to use glass fibre reinforced plastic material
in
EP 852 280. Furthermore, plastics spacers including stabilising material in a plastic body have
been proposed e.g. in
WO 99/15753 or in
WO 99/41481. However, these solutions have also some disadvantages. In particular, manufacturing
is relatively complicated.
[0009] Similar spacers made from a body of plastic material are further known from
DE 9 214 799,
EP 1 022 424,
EP 947 659 A2,
EP 1 233 136 A1,
WO 99/42693 or
WO 03/074830. In
US 5 630 306 there is disclosed an insulating spacer which comprises a main body formed of a plastic
material. Metallic leg members are attached to the plastic main body. While the problem
of heat conduction and diffusion can be addressed with such spacer, some problems
remain in context with bending the spacer into the desired frame shape and later during
assembly of an IG Unit. In particular, the lateral legs may be deformed during bending
out of their plane so that an irregular shape may result. Such an irregular shape
is particularly disadvantageous if a sealing contact between the spacer and a glass
pane shall be achieved.
[0010] Another way of making spacers with a low heat conductivity could be by making the
spacers from thin materials, thereby the amount of material is reduced but this also
results in a soft and flexible spacer being difficult to handle while mounting between
panes.
Object of the Invention
[0011] It is therefore an object of the present invention to provide a spacer with an increased
stiffness and solving the above mentioned problems.
Description of the Invention
[0012] This is obtained by a spacer for forming a spacing between glass panes, with a top
part and a lower metal foil, wherein said top part has an inner wall part with overlap
surfaces at each end for connecting to said metal foil, and wherein said metal foil
has an outer wall part and two lateral sidewalls extending from said outer wall part,
and towards said top part. Each end of said lateral side walls comprises an overlap
surface parallel to each overlap surface of said top part, wherein the overlap surfaces
are substantially parallel to the lateral sidewalls of said metal foil and wherein
said overlap surfaces are mutually fastened in a region closer to the inner wall part
than the outer wall part.
[0013] By having overlapping regions at the side walls the spacer is stiffened because of
this overlap, thereby spacers can be produced of quite thin material e.g. where also
the top part is made from a metal foil. The overlapping region at both side of the
spacer ensures a stiffer spacer which can be handled easier. Further by fastening
the overlapping surfaces close to the top part, when attaching the spacer between
panes the used attachment material e.g. butyl ensures that the attachment is sealed.
It is thereby ensured that gas from between the windows cannot pass the spacer through
the connection between the top part and the lower metal foil. Further overlapping
is present at both sides of the spacer and this also introduces a quite stiff spacer,
even if the spacer is made from a thin material.
[0014] In an embodiment said top part further comprises a second overlap surface at each
end, whereby said overlap surfaces at each end of said sidewalls of said metal foil
are mutually fastened between said first and second overlap surface at each end of
said inner wall part. Thereby a better fastening can be obtained between the two parts
of the spacer, the metal foil overlap surfaces at the end of sidewalls are sandwiched
between the first and second overlap surface at each end of the inner wall part.
[0015] In an embodiment the spacer further comprises overlap surfaces being substantially
parallel to the inner wall part of said top part. Thereby the spacer is further strengthened.
[0016] In another embodiment the overlap surfaces are substantially parallel to the lateral
sidewalls of said metal foil. Thereby the top part and metal foil are easy to assemble
for specific assembling methods.
[0017] In an embodiment the top part is made of metal foil. Thereby the spacer becomes very
resistant to gas diffusion.
[0018] In an embodiment the top part is made of a plastic material. Thereby heat conductivity
is reduced.
[0019] In an embodiment said overlapping surfaces are mutually fastened by welding. This
has been proven to be a very efficient way of fastening, where the overlap can be
mutually fastened by spot welding from one side of the overlapping surfaces.
[0020] In an embodiment said overlapping surfaces are mutually fastened by gluing.
[0021] The invention further relates to a method of producing a spacer for forming a spacing
between glass panes, comprising the steps of:
- Providing an elongated top part having overlap surfaces at each end for connecting
to a metal foil,
- Providing a metal foil with sidewalls having overlap surfaces,
- Attaching said metal foil and said top part to each other in such a way that the overlap
surfaces at each end of the elongated top part and the overlap surfaces of the sidewalls
of the metal foil are overlapping, and mutually fastening said overlap surfaces.
[0022] The invention further relates to a window comprising glass panes being mutually spaced
by a spacer according to the invention.
Description of the Drawing
[0023] In the following embodiments of the present invention will be described referring
to the figures, wherein
figure 1 illustrates a sectional view of an embodiment of a spacer according to the
present invention,
figure 2 illustrates a sectional view of the spacer of figure 1 mounted between panes,
figure 3-5 illustrates a sectional view of alternative embodiments of the spacer according
to the present invention.
Detailed Description of the Invention
[0024] Figure 1 illustrates a sectional view of an embodiment of a spacer 101 for forming
a spacing between panes according to the present invention. The spacer 101 comprises
a top part 103 and a lower metal foil 105.
[0025] The top part 103 has an inner wall part 107 with corresponding overlap surfaces at
each side being respectively 109, 112 and 110, 111 at each end for connecting to the
lower metal foil 105. The top part can be in a thin material being either metal or
plastic and could either be made by bending or extrusion. The material chosen influences
both heat conductivity and the ability to resist gas diffusion.
[0026] The lower metal foil 105 has an outer wall part 113 and two lateral legs or sidewalls
115, 117 extending from the outer wall part 113 and towards the top part 103. Each
end of said lateral side walls 115, 117 comprises an overlap surface 119 at one side
and 121 at the other side being parallel to each overlap surface 109, 111 of the top
part 103. The overlap surfaces of respectively the top part and the lower metal foil
are substantially parallel to the lateral sidewalls 115, 117 of the metal foil 105
and thereby the side of the spacer ends up having layers of material at each side
(in this example three layers) the layers in one side being 111, 119, 110 and in the
other side being 112, 121, 109. By having these layers it is possible to make the
spacers from quite thin materials e.g. metal foils and still obtain a stiff spacer,
the stiffness caused by the overlapping.
[0027] As can be seen from the figure, the overlapping area are quite close to the inner
wall and in the top part of the spacer and thereby the overlap surfaces can be mutually
fastened in a region closer to the inner wall part than the outer wall part.
[0028] In figure 2 a sectional view of the spacer 101 of figure 1 mounted between panes
201, 203 are illustrated. The spacer is mounted to the panes using a fastening material
205, 207 being e.g. butyl or another material being suitable for connecting the materials
of respectively the sides of the spacer and the panes, further the fastening material
should resist gas diffusion. The fastening material is below the overlapping area
(encircled area 209, 211) where the two parts are fastened and thereby the only way
gas can get from between the two panes 201, 203 and out is through the lower metal
foil 113 or through the fastening material 205, 207.
[0029] In figure 3 an alternative embodiment where only two layers are overlapping parallel
to the side walls (encircled areas 209, 211). In this embodiment further overlapping
surfaces are present being substantially parallel with the inner wall of the top part.
These further surfaces are illustrated by respectively 305 and 301 on the lower metal
part 105 and 303 and 307 on the top part 103. Thereby the spacer is further strengthened.
[0030] In figure 4 another embodiment is illustrated where two layers are overlapping parallel
to the side walls (encircled areas 209, 211). In this embodiment the top part has
been bended having peaks 401, 403. It is thereby possible to obtain a larger overlapping
area at the top part of the spacer and thereby a better attachment of the two parts.
Further the shaping of the spacer is optimised for influencing the bending properties
of the spacer when bending to fit the geometry of the panes.
[0031] In figure 5 another embodiment of the spacer is illustrated where two layers are
overlapping parallel to the side walls (encircled areas 209, 211). In this embodiment
both peaks 401, 403 are3 present as well as a further overlapping being substantially
parallel with the inner wall of the top part illustrated by respectively 305 and 301
on the lower metal part and 303 and 307 on the top part.
1. A spacer (101) for forming a spacing between glass panes (201, 203), with a top part
(103) and a lower metal foil (105),
wherein said top part (103) has an inner wall part (107) with overlap surfaces (110,
111, 109, 112) at each end for connecting to said metal foil (105),
and wherein said metal foil (105) has an outer wall part (113) and two lateral sidewalls
(115, 117) extending from said outer wall part (113), and towards said top part (103)
characterised in that
each end of said lateral side walls (115, 117) comprises an overlap surface (119,
121) parallel to each overlap surface (109, 111) of said top part (103), wherein the
overlap surfaces (110, 111, 119, 109, 112, 121) are substantially parallel to the
lateral sidewalls (115, 117) of said metal foil (105) and wherein said overlap surfaces
(119, 111) are mutually fastened in a region closer to the inner wall part (107) than
the outer wall part (113).
2. A spacer according to claim 1, wherein said top part (103) further comprises a second
overlap surface (110, 112) at each end, whereby said overlap surfaces (119, 121) at
each end of said sidewalls (115, 117) of said metal foil (105) are mutually fastened
between said first (110, 112) and second (109, 111) overlap surface at each end of
said inner wall part (107).
3. A spacer according to claim 1-2, wherein the spacer further comprises overlap surfaces
(301, 303, 305, 307) being substantially parallel to the inner wall part (107) of
said top part (103).
4. A spacer according to claim 1-3, wherein the top part is made of metal foil.
5. A spacer according to claim 1-4, wherein the top part is made of a plastic material.
6. A spacer according to claim 1-5, wherein said overlapping surfaces are mutually fastened
by welding.
7. A spacer according to claim 1-5, wherein said overlapping surfaces are mutually fastened
by gluing.
8. A method of producing a spacer (101) for forming a spacing between glass panes (201,
203), in particular for a spacer according to any of the claims 1 to 7, comprising
the steps of:
• Providing an elongated top part having overlap surfaces at each end for connecting
to a metal foil,
• Providing a metal foil with sidewalls having overlap surfaces,
• Attaching said metal foil and said top part to each other in such a way that the
overlap surfaces at each end of the elongated top part and the overlap surfaces of
the sidewalls of the metal foil are overlapping, and mutually fastening said overlap
surfaces.
9. A window comprising glass panes (201, 203) being mutually spaced by a spacer (101)
according to any of the claims 1 to 7.