Note: Descriptions are shown in the official language in which they were submitted.
CA 0222239~ 1997-11-27
Arrangement for In~talling Gla~ Cer~mic Cooking 8urfa¢e~ in an
Edge Area That Tapers to a Thin Edge at a Sill Pl~te
The invention relates to an arrangement for installing glass
ceramic cooking surfaces on a sill plate with a glass ceramic plate
that has an edge area which tapers to a thin edge in the form of a
circumferential polished bevel.
As part of the kitchen fixtures, glass ceramic cooking
surfaces are subject, like the kitchen furniture itself, to
fashionable, design trends that attempt to produce aesthetically
pleasing forms. Thus, the market now calls for glass ceramic
cooking surfaces with special edge designs that have edge areas
which taper to a thin edge, preferably glass ceramic cooking
surfaces with a round-circumferential flat polished bevel.
There are already glass ceramic cooking surfaces on the market
that are beveled at the edges and are installed on the latter in a
cutout in the kitchen sill plate without any edge protection.
While known mirror glass that is equipped with round-
circumferential flat polished bevels for the associated special
aesthetics requires no further edge protection except for shipping
protection since it can be assumed that this mirror glass --
suspended on the wall or incorporated into furniture -- will not be
exposed to any m~r-h~n;cal loads, in practice glass ceramic cooking
surfaces are exposed to major mechanical loads which, without
suitable edge protection, create a considerable risk of breakage.
In particular, lateral shocks to the edge which, in the known case,
is open and relatively thin, e.g., when pots are moved around on
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the sill plate, create, with this type of glass ceramic cooking
surface, a considerable risk of breakage, possibly leading to
injury for the user, although glass ceramic cooking surfaces
without such edge mach;n;ng and that are installed in suitable
frames can now withstand the above-mentioned loads.
The object of the invention, starting from the above-mentioned
arrangement, is to configure said arrangement in such a way that,
on the one hand, the aesthetics of the cooking surfaces that are
beveled on the edge are still ensured and, on the other hand, an
open edge is avoided.
This object can be accomplished according to the invention
with a layer arrangement that is made of a permanently elastic
material which encases the front of the edge and the lower side of
the beveled edge area, whereby the arrangement, which is designed
in the shape of a frame, is made in such a way that the edge is not
exposed to direct mechanical shock stress from the side and/or from
above.
Because of the edge protection measure according to the
invention, the risk of breakage of the beveled glass ceramic
cooking surface is significantly reduced, and the drawbacks that
are described in connection with their known arrangement are
avoided to a large extent, without their desired aesthetic impact
being impaired.
A glass ceramic cooking surface with a special edge design is
known in the art from DE 43 04 370 C2. The known case is a cooking
surface that is chamfered on one edge, i.e., has a bevel that runs
from the top to the bottom, which is encased by an inclined section
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of an edging frame with an intermediate sealing contour. Using a
clamping device, the two bevels can be pressed very tightly
together to provide a very tight connection between the glass
ceramic cooking area and the edging frame. The visible ledge of
the edging frame and the upper edge of the cooking surface are in
this case flush with one another when installed, with the chamfered
bevel being completely covered, wheréby the visible ledge can also
be placed somewhat lower.
In addition, a cooking area glass ceramic plate with a bevel
in the edge area is known from DE 32 27 058 A1, whereby an elastic
edge protective element that encases the cooking area edge adjoins
the end of the bevel. In this known arrangement, the only purpose
of the bevel is to protect the cooking area edge from breakage,
i.e., the bevel itself therefore serves as edge protection. It is
intended to protect the edge from damage by shock stress. The
purpose of the bevel is therefore ultimately to improve the edge
area mechanically by virtue of the fact that the usually vertical
edge of the glass ceramic plate from which cracking may arise as a
result of muscling-out or the like is broken up.
Just as the already considered DE 43 04 370 C2, the previously
mentioned DE-OS thus deals with a bevel that is relatively steep
and has nothing to do with a polished bevel. This is also shown in
the fact that the edge protective element can overlap the bevel,
which is at odds with a purely optically aesthetic bevel, i.e., an
aesthetically pleasing bevel.
The edge-side polished bevel according to the invention is
more than a simple edge bevel. In the case of a polished bevel,
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the edge area very gradually tapers at a shallow angle to a very
thin edge. In terms of mechanics, this polished bevel leads to a
weakening of the plate, and therefore the risk of damage also
increases since the glass ceramic plate is designed to be thinner
over a comparatively large edge area. The known bevel and the
bevel of the cooking area-glass ceramic plate according to the
invention therefore have completely different objects. What is
important in the invention is to protect the thin edge of the
polished bevel while preserving the aesthetic impact of the bevel,
an object that is not set in the known case.
In this known case, the type of glass ceramic cooking areas
that is described above does not exist. Since it is completely
covered when installed, the chamfered edge serves, unlike the
beveled cooking surfaces, not the above-described aesthetic
purposes, but rather has exclusively an attaching function.
Special advantages with respect to the risk of breakage at
minimized expense are achieved corresponding to a further
development of the invention if the layer thickness of the front
permanently elastic layer is between 0.3 and 0.7 mm and preferably
0.5 mm.
For the protection of the thin edge of the beveled edge area,
there are various possible concepts. According to an embodiment of
the invention, a concept exists whereby the glass ceramic cooking
surface is provided with circumferential edge protection by
encasing the permanently elastic layer with a hard, energy-
distributing, impact-resistant layer and can be installed on the
latter as a unit in a cutout in the sill plate. As a result,
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shipping protection is also advantageously ensured by the
installation-edge protection if the hard layer is attached
immediately after the glass ceramic cooking surfaces is machined.
In this case, it is not absolutely necessary to place the unit
on the sill plate. It is also conceivable to provide a recessed,
round-circumferential section in the cutout of the sill plate on
which the cooking surface rests flush with the sill plate surface.
To ensure unity of the cooking surface, the permanently
elastic layer and the hard layer are preferably tightly connected
together, preferably glued together according to a simple design.
The permanently elastic layer can be made from various
materials. It can consist of, e.g., a silicone adhesive that is
applied as a layer, which can be marketed together with glass
ceramic materials for cooking surfaces. There may also be
advantages with respect to production, however, if the permanently
elastic layer consists of a rubber profile, preferably silicone
rubber, that is vulcanized directly onto the glass ceramic cooking
surface.
Since it is especially advantageous from the standpoint of
production and installation it is especially advantageous if,
according to a further development of the invention, the hard layer
is formed by a round-circumferential profile that is made of metal
or plastic.
To minimize shock stress from above, it is advantageous if,
according to an additional embodiment of the invention, the hard
layer extends above the permanently elastic layer on the front of
the edge by a specific amount, preferably 0.5 mm. A shock stress
CA 0222239~ 1997-11-27
from above then strikes the upper edge of the hard layer first, in
particular the profile.
According to another embodiment of the invention, another
concept of edge protection consists in the fact that the glass
ceramic cooking surface is provided only with the permanently
elastic layer on the lower side and a supporting frame attached
thereto, recessed in a cutout of the sill plate with the supporting
frame, and the encasing of the front of the edge with the
permanently elastic layer is done after it is installed. An
arrangement that is designed in this way is especially advantageous
for flush installation into the cutout of a sill plate.
In this case, according to a further development of the
invention, it is especially advantageous with respect to
installation if the permanently elastic layer is formed on the
front of the edge by an adhesive layer, preferably made of a
silicone adhesive, that fills the joint between the edge and the
sill plate cutout.
For installation inside the cutout of the sill plate, various
options are open to one skilled in the art. A very simple kind of
installation that involves no visible frame and is thus economical
is possible if, according to an embodiment of the invention, the
sill plate cutout has a round-circumferential shoulder on which the
glass ceramic cooking surface rests with the leg of the supporting
frame that is fastened to the lower side of the tapered edge area.
According to another further development, the installed arrangement
is aesthetically pleasing if an installation-subframe is attached
to the sill plate cutout with an upper leg that is designed as a
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visible frame and that rests on the sill plate and a lower leg that
carries the supporting frame.
Corresponding to the first concept, it is advantageous for
minimizing shock stress from above if, when installed, the edge of
the glass ceramic cooking surface ends with the highest projection
on the sill plate side, and preferably is arranged a certain
smaller distance below.
Other configuration features and advantages~of the invention
are indicated in the description of the embodiments that are
depicted in the drawings.
Here:
Fig. 1 shows a beveled glass ceramic cooking surface with
round-circumferential edge protection, formed by a
metal profile for installation on a sill plate,
Fig. la shows a first variant of the embodiment according
to Fig. 1 with a profile that extends flat,
Fig. lb a second variant of the embodiment according to
Fig. 1 with a profile that has an edge bead,
Fig. 2 a beveled glass ceramic cooking surface which, with
the aid of an installation-subframe, is installed
recessed in the cutout of a sill plate, while
forming edge protection in the installed state,
Fig. 2a a first variant of the embodiment according to Fig.
2 with a sloped visible ledge of the installation-
subframe,
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Fig. 2b a second variant of the embodiment according to
Fig. 2 with a bead-like visible ledge of the
installation-subframe,
Fig. 3 another embodiment for installing the permanently
elastic layer on the beveled glass ceramic cooking
surface, and
Fig. 4 a beveled glass ceramic cooking surface, which is
installed without a frame, recessed, in the cutout
of a sill plate, while forming the edge protection
in the installed state.
Fig. 1 shows glass ceramic cooking surface 1 that is beveled
at its edges with a tapering edge area la and beveled, thin edge
lb. The edge of glass ceramic cooking surface 1 is encased by a
round-circumferential metal profile 2. In this case, the portion
of profile 2 that is laterally higher is designed in such a way
that its upper edge 2c ends with beveled edge lb of the cooking
surface or preferably projects slightly (e.g., 0.5 mm) so that a
shock stress from above strikes only the profile edge.
Metal profile 2, as a preferred embodiment of a hard, energy-
distributing and shock-resistant layer, comprises a layer made of
permanently elastic material that is between it and the beveled
edge area and that also absorbs the shock energy which arises when
work is done on the cooking surface.
This layer consists of an adhesive layer 3, preferably made of
silicone adhesive, that is attached to the lower side, absorbs
shocks from above and, moreover, mainly has the function of
attaching glass ceramic cooking surface 1 to metal profile 2. This
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adhesive layer 3 has the usual thickness of 1.5 mm, but at least 1
mm.
The lateral protection of cooking surface edge lb is ensured
by the fact that a thin adhesive layer 3a is provided between
profile leg 2a and the front of edge lb of cooking surface 1.
Tests have shown that, even at a layer thickness of as little
as about 0.5 mm, the damping of shock stress from the side is
enough to protect the edge of the cooking surface. This adhesive
layer 3a, which is thin compared to adhesive layer 3, also has the
advantage that profile 2 adjoins cooking surface 1.
Starting from a thickness of glass ceramic plate 1 in Fig. 1
of about 4 mm, the length of section la that tapers to edge lb
typically is about 10 to 15 mm with a thickness of edge lb in the
range of < 2.5 mm. The length of the lower leg of profile 2, which
also ensures mechanical enhancement of the beveled edge area, is
determined based on the length of the tapered section.
Circumferential profile 2 with circumferential adhesive layers
3, 3a ensures effective edge protection against shock stresses that
commonly occur when glass ceramic cooking surfaces are used.
If profile 2 is attached with permanently elastic layers 3, 3a
-immediately after glass ceramic cooking surface 1 is machined,
shipping protection during shipping from the manufacturer of the
glass ceramic cooXing surface that is provided with edge protection
to the site where it is installed is provided at the same time as
edge protection in the installed state.
As depicted in Fig. 3, the permanently elastic layer, instead
of adhesive layers 3, 3a in Fig. 1, can also be a rubber profile 12
_g_
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that consists of, for example, silicone rubber and that is
vulcanized directly onto the edge area of the glass ceramic plate.
Also suitable are molded polyurethane profiles, whose hardness is
adjusted in such a way that, on the one hand, deformation is
largely avoided, but in the case of shock stresses, the material
has an energy-absorbing action like a crush zone. Such profiles
are usually produced in an injection-molding form, into which the
molded-in edge portion of the glass ceramic cooking surface is
first inserted. In this case, the color scheme depends on the
designer's wishes.
A thin coating of the glass ceramic cooking surface with a
transparent or black tinted rubber-like material, which reduces the
above-described shock energy on the cooking surface, is also
conceivable.
For the profile, various embodiments are conceivable that are
depicted as examples in Figs. la and lb. In this case, Fig. la
shows a profile 2a that extends flat, while Fig. lb shows a profile
with a pronounced edge bead 2b. Which embodiment is used depends
mainly on the kitchen design that is present in each case.
Moreover, the embodiments according to Figs. la and lb are
identical to that according to Fig. 1.
As materials for profile 2, 2a or 2b, e.g., aluminum profiles,
which are preferably anodized black, are suitable. Also, however,
color-varnished high-grade steel profiles or plastic profiles that
are made of unbreakable, temperature-resistant material are
conceivable.
--10--
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The arrangement according to Fig. 1 or Fig. la and Fig. lb is
used, in this case, for installation on a kitchen sill plate above
a cutout in said sill plate.
Fig. 2 shows another arrangement according to the invention,
in which beveled cooking surface 1 is installed recessed in the
cutout of sill plate 10. In this cutout, installation-subframe 4
is previously inserted and attached using screws 8. Installation-
subframe 4 has an upper leg 4a that is designed as a visible ledge
and that rests with its end 11 on the top side of sill plate 10, as
well as a lower leg 4b for supporting a supporting frame 5.
In this installation-subframe, the commonly used cooking area
design that consists of ceramic cooking surface 1 and is glued over
a layer 3 with an upper leg 5a of supporting frame 5 is used and is
fastened in the installation-subframe by virtue of the fact that
its lower leg 4b is connected to a lower fastening leg 5b of
supporting frame 5 using commonly employed fastening means 9.
Then, the joint between installation-subframe 4 and edge lb of
beveled glass ceramic cooking surface 1 is filled, while forming an
adhesive layer 7, with an adhesive material, preferably a silicone
adhesive.
A circumferential foam profile 6 (adhesive strip or sprayed as
a sealing bead) is also attached to supporting frame 5, which, when
the joint is glued, prevents the adhesive from getting inside and
thus ensures cleaner removal of the adhesive joint.
The installation of glass ceramic cooking surfaces in a cutout
of a sill plate using an installation-subframe is known in the art
from DE 44 34 821 A1. In contrast to the known design of the
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installation-subframe, the upper leg of the frame is designed as a
visible ledge in the use according to the invention and is just
wide enough (about 3 to 5 mm) that cutting tolerances are
overlapped when the sill plate cutout is machined.
The geometry of the overall arrangement according to Fig. 2 is
designed in such a way that edge lb of cooking surface 1 ends with
the edge of visible ledge 4a or preferably is arranged somewhat
recessed.
Figs. 2a and 2b show other variant embodiments of visible
ledge 4a of installation-subframe 4. In the case of the embodiment
according to Fig. 2a, visible ledge 4a is designed like a slope;
conversely, in the case of the embodiment according to Fig. 2b,
visible ledge 4a is designed like a bead. Moreover, as the
identical reference symbols also indicate, the two embodiments are
identical to that according to Fig. 2.
In the case of stone or plastic sill plates, designs are also
conceivable that make do without visible frames since in these sill
plates, precise machining of the cutout edge is made possible by
milling. As a result, in contrast to wooden sill plates, a cleaner
edge end at the adhesive joint is possible. SCHOTT Information
2/84 shows in Fig. 4c such a flat installation option.
Fig. 4 shows a simplified variant with a frame-less recessed
installation of beveled cooking surface 1 in the cutout of a sill
plate 10. In this case, the cooking area structure, which consists
of cooking ~urface 1, is placed, already glued to supporting frame
5, on a round-circumferential section lOa of sill plate 10. Then,
the joint is filled using a silicone adhesive to form a layer 7.
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CA 0222239~ 1997-11-27
In this case, supporting frame S is attached in the usual way to
the sill plate.
Otherwise, the same reference symbols are similar to the
features of Figs. 1-2.
With the previously described arrangements, installation
options are shown for glass ceramic cooking surfaces with special
edge mac-hining (bevels) which, on the one hand, ensure adequate
protection of such edge embodiments and, on the other hand,
highlight the special aesthetics of this edge embodiment.
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