Note: Descriptions are shown in the official language in which they were submitted.
CA 02544767 2006-04-13
A kitchen utensil
The present invention is related to a kitchen utensil, in par-
ticular to a kitchen utensil that may be used as a keep-fresh
lid, as a microwave oven lid or as a mat.
In the field of keep-fresh containers, keep-fresh boxes are
known consisting of a container portion and a lid, wherein a
vacuum may be generated within the container portion when the
lid has been put thereon, the vacuum contributing in keeping
somewhat longer fresh a foodstuff within the keep-fresh box.
German Utility Model specification DE 82 27 597 U1, for exam-
ple, discloses a vacuum provisions container for easily perish-
able products. A manually operable air pump is integrated into
the lid of that prior art container. When the lid is put on,
the user can generate a vacuum within the container by pushing
down the lid several times.
This prior art container has the disadvantage that on the one
hand a lid of complicated design is required that may be manu-
factured only at correspondingly high costs. The lid, further,
is difficult to clean which is of particular disadvantage for
kitchen utensils that come into contact with perishable food-
stuffs. Finally, both hands must be used for actuating the pump
mechanism because one hand has to firmly grip the container and
the other hand must push down the lid.
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German patent specification DE 17 79 293 B2 discloses a keep-
fresh box. This prior art box has a lid being convex in its
rest position and being of an elastic material. The lid is put
on a container portion with a snugly fitting rim. The lid is
then pressed down by hand and is turned down until it assumes a
convex shape entering into the container portion. When doing so
air escapes from the container portion because corresponding
ribs are provided at the bottom side of the lid in the area
where it rests on the container portion rim. The lid is now
grasped by means of a ring provided at a top side thereof, and
is pulled upwardly, i.e. turned up which results in the forma-
tion of a vacuum within the container portion.
This prior art keep-fresh box has the disadvantage that it is
quite cumbersome to handle. Moreover, the lid may only be used
together with a container portion being exactly matched thereto
in shape. Further, the design of the lid is difficult because
its deformation behaviour must exactly be such that the convex
shape remains stably unchanged after the turning up although
there is a vacuum inside. Finally the turning up and down im-
poses a considerable alternating load on the rim portion of the
lid such that it may not be excluded that the rim will break
already after a relatively short time period of use.
In the field of lids adapted to be used in microwave ovens,
hereinafter referred to as "microwave lids", lids are known
that are put like a hood on a tray that contains a foodstuff
which shall be heated up in the microwave oven. Considering
that the heating up takes place very quickly and the foodstuff
may spurt, the lid is required in order to protect the interior
of the microwave oven against such spurts, for example grease
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spurts. On the other hand, the lid must not close the tray
tightly because the lid might be blasted away due to the rapid
heating up causing the formation of an overpressure within the
tray. Prior art microwave lids, therefore, have openings in
their upper portion allowing a pressure compensation. However,
grease spurts may escape through such openings.
In the field of mats, configurations of the most different kind
are known for protecting a sensitive surface, for example a
wooden surface of a kitchen table or of a dining table against
soiling or against a scorching damage, when a hot pot or a hot
pan is put down on that surface. Prior art mats, therefore,
consist of a thermally insulating material (wood, plastic mate-
rial, tissue) and are plate-shaped.
These prior art devices have in common that they are adapted to
be used solely for their own purpose. In the field of keep-
fresh containers, for example, the particularly used lid may
only be used for a particular container portion. However, in
particular within a kitchen it is desirable, in view of the
available space, to provide utensils that may be used for a
variety of different uses.
It is, therefore, an object underlying the invention, to de-
velop further a kitchen utensil of the type specified at the
outset such that a multiple-use utensil is made available
which, moreover is superior in a particular field of use to
conventional utensils from that field of use.
In a kitchen utensil of the type specified at the outset this
object is achieved in that it comprises a disk-shaped body
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configured as a tense elastic foil in its central area and
being reinforced at its rim.
The object underlying the invention is entirely solved in this
surprisingly simple manner.
If, namely, the kitchen utensil is put on the rim of a con-
tainer portion of a keep-fresh container, it is sufficient to
slightly press down the central area of the kitchen utensil for
effecting a long-term and effective closure of the container
portion. The tensed foil, namely, acts as a membrane which
displaces air from the container portion when pressed down and
generates a vacuum within the container portion upon returning
elastically. Experiments have shown that this vacuum remains
for several days and, further, may be subjected to mechanical
stress. The handling of the kitchen utensil is extremely simple
because the user can lay the kitchen utensil down on the con-
tainer portion and can press the foil down thereafter with the
same hand. In contrast to the prior art discussed above the
container portion needs not to be firmly held by the other
hand.
The kitchen utensil according to the present invention may be
used for keep-fresh boxes, keep-fresh trays and the like in
order to prevent that sensitive foodstuffs like salads, sauces,
ice cream and the like perish prematurely.
The kitchen utensil, however, may likewise be used as a protec-
tive lid that prevents an unintentional spilling of, for exam-
ple liquid contents of foodstuff containers. Experiments have
shown that the kitchen utensil of the present invention may
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advantageously be used as a cover for a beer mug when the lat-
ter is brought from a bar to a table within a restaurant which,
in the case of a beer garden or of a marquee may be located at
a considerable distance from the bar. Tf a waiter carries sev-
eral beer mugs simultaneously it may happen under crowded cir-
cumstances that beer is spilled over on the clothing of guests.
This may be reliably prevented when the kitchen utensil of the
present invention is used. In that use, the kitchen utensil
sticks to the filled beer mug so tightly that, as has been
found out in the course of the experiments mentioned above, the
mug may even be held upside down without the beer leaking out.
The kitchen utensil of the present invention, further, may be
used as a microwave lid. In that case it is advantageous that
the lid, lying loosely on a microwave tray, on the one hand
enables a pressure compensation between the interior of the
microwave tray and the exterior and, on the other the closed
surface of the foil prevents spurting out. This holds true, in
particular, when the kitchen utensil is provided with certain
further preferred features. The same holds true for the use as
a mat. This and other uses will be discussed further below.
The kitchen utensil of the present invention may be configured
in different ways. It is preferred when it is configured circu-
lar disk shaped or oval or rectangular.
This measure has the advantage that the kitchen utensil may be
configured optimally depending on how it is intended to be
used.
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In a preferred embodiment of the invention the rim is integral
with the foil.
This measure has the advantage that the kitchen utensil may be
manufactured easily by molding process, in particular by injec-
tion molding process.
A particularly good effect is achieved when the foil is config-
ured smooth on one surface.
This measure has the advantage that for the use as a keep-fresh
lid the vacuum within the container portion may be held over a
long period of time when the smooth surface snugly fits to the
rim of the container portion.
This holds particularly true when the foil consists of sili-
cone.
This measure has the additional advantage that silicone is a
material which is uncritical under foodstuff safety standards.
Moreover, utensils made from silicone may be manufactured with
smooth, almost sticky surfaces. Finally, silicone is heat re-
sistant up to about 250° C and is thermally insulating which is
of importance for a use as a mat.
It is, further, preferred when the foil has a thickness of
between 0.5 and 2 mm, preferably of between 1 and 1.5 mm.
These dimensions have turned out to be optimal during experi-
ments, in particular when silicone is used.
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In embodiments of the invention the foil is provided with a
reinforcement in a center of the central area.
In case of a use as a keep-fresh lid this measure has the ad-
vantage that the point being mechanically stressed during
pressing down is configured reinforced, so that foil fracture
damages caused by continuing deformation must not be expected.
Practically, the reinforcement is configured as a thickening of
the foil.
This, too, has the advantage that the kitchen utensil may be
manufactured as a whole by one injection molding operation.
In further embodiments of the invention the rim is reinforced
by an embedded metallic reinforcing element, in particular by a
ring.
This measure has the advantage that the reinforcement may be
effected by a relatively small element, which, in turn may be
embedded in the course of an injection molding operation.
In a further development of the invention the rim has a height
being essentially two to six times, preferably four to five
times as big as the thickness of the foil.
This measure, on the one hand, has the advantage that there is
sufficient space at the rim for providing there a reinforcing
element. On the other hand, in the event of a use as a mat
there is the advantage that the hot pot is held with its bottom
at a distance from the sensitive surface e.g. of the dining
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table, wherein the air cushion between the bottom and the sur-
face additionally acts as thermal insulation in addition to the
foil.
In this context it is also preferred when the rim is as high as
the reinforcement.
In case of a use as a mat this measure has the advantage that
the pot bottom is also supported in its center, so that the
weight load does not only rest on the rim.
Another group of embodiments of the invention is characterized
in that the foil is provided with a plurality of ribs on a
surface thereof, the ribs extending from a rim in a direction
towards a center of the kitchen utensil.
In particular in case of a use as a microwave lid this measure
has the advantage that a still more effective pressure compen-
sation is made possible between the interior of the microwave
tray and its exterior through the interstices between the ribs,
without negatively affecting the covering action of the foil
because the pressure compensation happens at the bottom side of
the lid.
In further variations of this embodiment the ribs have a length
being one half of the distance between the rim and the center.
Further, the ribs have a height being smaller than a height of
the rim.
Further advantages will become apparent from the description
and the enclosed drawing
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It goes without saying that the features mentioned before and
those that will explained hereinafter may not only be used in
the particularly given combination but also in other combina-
tions or alone without leaving the scope of the present inven-
tion.
Embodiments of the invention are shown in the drawing and will
be explained in the subsequent description.
Figure 1 shows a top plan view of a kitchen utensil according
to the present invention;
Figure 2 shows a side elevational, sectional view of the
kitchen utensil of Figure 1 on a somewhat enlarged
scale;
Figures 3A and 3B show a schematic side elevational view of a
first use of a kitchen utensil of the present inven-
tion as a keep-fresh lid, in two operational condi-
tions;
Figure 4 shows a schematic side elevational view of a second
use of a kitchen utensil of the present invention as
a microwave lid;
Figure 5 shows a schematic side elevational view of a third
use of a kitchen utensil of the present invention as
a mat.
, CA 02544767 2006-04-13
In Figures 1 and 2 reference numeral 10 as a whole designates
an embodiment of a kitchen utensil according to the present
invention. Kitchen utensil 10 is provided with a disk-shaped
body 12. In the embodiment shown, body 12 has a circular shape,
however, it may likewise be shaped oval or rectangular or oth-
erwise, to the extent as this is technically possible and makes
sense in the present context.
In its inner area, body 12 consists of a plane foil 14, and in
its outer area it consists of a reinforced rim. The reinforce-
ment thereof is configured by a reinforcing element 18, for
example by a metallic ring. The reinforcing element is, pref-
erably, embedded in rim 16.
Foil 14, preferably, is made from silicone and is integral with
rim 16. Through the thermal production process of molding or
injection-molding, foil 14 is tensed within the reinforcement
of rim 16 during the cooling down and acts as a membrane or a
drum skin.
Ribs 20 are provide on a first surface being an upper surface
in Figure 2. Ribs 20 extend with a length 1 in a radial direc-
tion from rim 16 to a center 23 of body 12, however, only along
a portion of the distance between rim 16 and center 23, namely
preferably along one half of that distance.
Further, a reinforcement 22 is provided at center 23, and is,
preferably, configured as a thickening of foil 14. Ribs 20 and
reinforcement 22, preferably, are likewise manufactured inte-
gral and together with foil 14.
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A second surface being the lower surface in Figure 2 is, pref-
erably, made smooth.
In practical embodiments, body 12 may have a diameter D being
of the same order of magnitude as the diameter of conventional
trays, pots or pans, i.e. between 10 and 40 cm. Diameters of
20, 24, 28, and 32 cm would be practical, for example as a set.
The thickness d of foil 14 may be in the range of between 0.5
and 2 mm depending on the material used and on the size of body
12. A range of between 1 and 1.5 mm would be preferred when
silicone is used and for the diameters D specified above.
The height H of rim I6 is two times to six times, preferably
four times to five times as big as thickness d of foil 14. Rim
16, further is as high as reinforcement 23, whereas ribs 20 are
configured somewhat flatter.
Figures 3 to 5 show three distinct uses of kitchen utensil 10.
In Figures 3A and 3B a first use of kitchen utensil 10 is
shown, namely as a keep-fresh lid l0a of a keep-fresh container
34.
As one can see, keep-fresh lid l0a was put with a rim area 30
of smooth, lower surface 24 on a rim 32 of a box 34 or a tray,
a beer mug or the like. Thereby, an interior 36 of box 34 is
closed.
If now a force is exerted on reinforcement 22 at center 23 of
foil 14, as illustrated by an arrow 38 in Figure 3B, foil 14,
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acting as a membrane due to its elasticity and its inherent
tension, will be deformed downwardly with its central area 13,
as indicated in Figure 3B with I3' and I4'. Interior 36 is,
thus, reduced to 36'. When the force is removed, deformed foil
14' will automatically return into its initial position 14 of
Figure 3A due to its elasticity and inherent tension. A vacuum
is now established within interior 36. As foil 14, consisting,
preferably, of silicone, tightly adjoins rim 32 with its smooth
surface 24, the vacuum remains over a long period of time.
Figure 14 shows a second use of household utensil 10 as a mi-
crowave lid.
In that case household utensil 10 is turned upside down, as
compared to the use according to Figures 3A and 3B, i.e, with
its ribs facing downwardly, and is then put with ribs 20 on a
rim 40 of a microwave tray 42. An interior 44 of microwave tray
42 is now, on the one hand, entirely covered upwardly because
foil 14 covers the entire interior 44. On the other hand, a
pressure compensation to the exterior is possible because air
may flow outwardly through the interstice between the ribs or
inwardly, as indicated by an arrow 46.
Figure 5, finally, snows still. a third use of household utensil
as a mat lOc.
As one can see, kitchen utensil 10 was put on a support 50, for
example a surface of a table, as a mat l0cwith ribs again 20
facing upwardly. A pot 52 or a pan or the like rests with a
bottom surface of its bottom .~6 on mat lOc, namely in the area
of rim 16, and, if the central reinforcement 22 is made with
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the same height, also on the latter. Thereby, between bottom 56
and support 50, there is not only foil 14 acting as a thermally
insulating element, but also an air cushion existing within the
interior of rim 16.
