WO2022223342A1

WO2022223342A1 - Cooktop, arrangement of such a cooktop, and method for sensing a weight load

Info

Publication number: WO2022223342A1
Application number: PCT/EP2022/059582
Authority: WO
Inventors: Marcus Frank; Marius Lehner; Max-Felix Müller; Ulrich WÄCHTER; Carmelo Zarcone
Original assignee: E.G.O. Elektro-Gerätebau GmbH
Priority date: 2021-04-21
Filing date: 2022-04-11
Publication date: 2022-10-27
Also published as: DE102021204007A1

Abstract

A cooktop includes a cooktop plate with heating devices underneath, a plurality of sensors in the edge region for sensing a weight load on the cooktop plate, and a cooktop controller connected thereto. Flat sensor strips made of elastic material are provided in the edge region of the cooktop plate and peripherally on the cooktop plate. Electrodes are provided on two opposite sides of the sensor strip in order to form at least one of the sensors. Said sensors are in the form of elongate flat strips. An additionally provided peripheral seal can be at a distance of no more than 10 mm from the sensor strip in order to seal, in particular liquid-tightly seal, the cooktop towards the outside.

Description

Hob, arrangement of such a hob and method for detecting a

weight load

FIELD OF APPLICATION AND PRIOR ART

The invention relates to a hob and an arrangement of such a hob on a worktop. Furthermore, the invention relates to a method for detecting a weight load on such a hob, in particular in an aforementioned arrangement on a worktop.

DE 102012216935 A1 discloses a hob with weighing sensors in the corner areas. These weighing sensors make it possible to record the weight of a pot placed on the hob and its location. To do this, all weighing sensors are queried, and the weight and location of the pot are determined from the respective sensor signals. In addition to the weighing sensors, a circumferential seal is provided between the hob plate and a worktop on which the hob is arranged, in order to seal a gap between the hob plate and the worktop that is necessary for movement.

DE 102015226052 A1 discloses a hob without a circumferential seal in a gap between the hob plate and the worktop. A circumferential channel is provided below this gap, which collects the liquid that enters, so that it can be easily removed from it. A negative influence of a seal on the accuracy of the detection of a weight load is thus avoided. For this purpose, this channel must be cleaned from time to time.

TASK AND SOLUTION

The invention is based on the object of creating a hob as mentioned at the outset, an arrangement of such a hob on a worktop and a method for detecting a weight load on a hob plate of this hob, with which problems of the prior art can be solved and in particular it is possible To be able to design the structure and arrangement of the hob as simply and practically as possible and to be able to record the weight load as precisely as possible.

This object is achieved by a hob with the features of claim 1, by an arrangement with the features of claim 16 and by a method with the characteristics Paint of claim 19. Advantageous and preferred embodiments of the invention are contained in the other claims and are explained in more detail below. Some of the features are only described for the hob, only for its arrangement or only for a method of detecting a weight load on it. Independently of this, however, they should be able to apply both to a hob and to an arrangement and also to a corresponding method independently and independently of one another. The wording of the claims is made by express reference to the content of the description.

The hob has a hob plate with an outer peripheral edge area and an outer edge, advantageously a hob plate made of glass ceramic. At least one heating device is arranged under the hob plate, advantageously four heating devices or even more. Furthermore, sensors are provided for detecting a weight load on the hob plate and a hob controller which is connected to the sensors and which is designed to evaluate and detect the weight load. At least three sensors are provided in the edge region of the hob plate, preferably one sensor each in at least three corner regions in the case of a rectangular hob plate.

According to the invention, at least one flat sensor strip made of elastic material is provided in the edge area of the hob plate, advantageously around 1 cm to 5 cm, and at least along 90% of a circumference around the hob plate or a circumference of the hob plate, preferably several sensor strips can be provided. The length of the at least one sensor strip is at least 5 times its width, advantageously the length is at least 10 times or even at least 40 times its width. Its width is at least twice as large as its height, advantageously 4 to 10 times as large. Electrodes are provided on two opposite flat sides of the sensor strip or of the plurality of sensor strips, in particular elongated electrodes with a longitudinal direction parallel to the longitudinal direction of the sensor strip. The electrodes are advantageously provided on an upper side and an underside of the sensor strip, with the upper side and underside particularly advantageously being able to run approximately in parallel planes to a plane of the hob plate. The sensor strip and the electrodes provided thereon form a sensor, with a sensor having or consisting of or being formed by two separate electrodes and at least one section of the sensor strip. The sensors are elongate along the circumference around the hob plate or along the circumference of the hob. The length of a sensor can be 10 mm to 300 mm, advantageously 30 mm to 80 mm. In the case of thin electrodes, a height of a sensor essentially corresponds to a height of the sensor strip; it can be 0.1 mm to 15 mm, advantageously 2 mm to 5 mm. The width of a sensor can be 5 mm to 50 mm, advantageously 10 mm to 20 mm. By the height of the sensor, first of all of the sensor strip, a sealing effect between the hob and a worktop on which the hob is to be arranged or is arranged can be at least partially achieved. The sensor strip is mainly responsible for this and the electrodes to a much lesser extent. At the same time, the sensor or the sensor strip should be sufficiently elastic so that the hob plate can be pressed down on it depending on a weight load. The distance covered, even if it should be very small, is taken as a measure of a weight load or a change in a weight load on the hob plate. This is known per se. Advantageously, the elasticity of the sensor strip is as linear as possible and/or as resistant as possible to aging, so that a connection between the weight load and the downward movement of the hob plate always remains the same as far as possible, even if the hob and in particular the sensor strip are several years old. The hob can be moved at least slightly against the elasticity of the sensor strip relative to a worktop on which it is arranged. A movement path can be between 0.001 mm and 5 mm, advantageously between 0.05 mm and 2 mm.

Furthermore, a circumferential seal is additionally provided on the hob plate, advantageously in the direction away from a central area of the hob outside the sensor strip, which has a maximum distance of 10 mm or maximum 20 mm from the sensor strip. You can also connect to the sensor strip or touch it, in particular it can be formed together with the sensor strip. The seal is advantageously made of the same material as the sensor strip. The seal is designed to seal off the hob from the outside, in particular to seal it in a liquid-tight manner, specifically in addition to the sensor strip.

With the additional seal, an even better sealing effect can be achieved overall, since on the one hand another seal is simply provided. On the other hand, this sealing device is arranged outside of the sensor strip and therefore catches liquid first, so that as little liquid as possible or no liquid at all reaches the sensors or the sensor strip.

In a first basic embodiment of the invention, the seal can be formed on the sensor strip or connected and formed in one piece with it. In this case, it can advantageously be formed on the outside of the sensor strip, that is to say pointing outwards or upwards away from a central area of the cooktop. It is particularly advantageous that the seal consists of the same material as the sensor strip. This is also an elastic material, which is basically suitable for a seal. In a further development of the invention, the seal can have a larger or thicker cross section than the sensor strip, as a result of which an improved sealing effect can be achieved. In particular, the sensor strip can be covered even better from the outside. An intermediate area without electrodes can preferably be provided between the seal and the sensor strip, so that the material can run from the sensor strip via this intermediate area to the seal. For example, it is possible to design the seal as an enlarged sealing lip that is formed or formed on the sensor strip.

In a second basic embodiment of the invention, the seal can be formed separately from the sensor strip, ie in a different way than described above. The seal then preferably consists of a different material than the sensor strip itself, in particular it can consist of an elastic material such as silicone or rubber. Alternatively, it can consist of a solid material, for example solid plastic or even metal, and form a seal with a precise shape or bring about a further sealing effect, advantageously grazing in front of the sensor. The seal and the sensor strip or the sensor formed by it preferably do not touch.

In a third fundamental embodiment of the invention, the seal can also be designed flat and separately from the sensor strip, but can be made of the same material as the sensor strip. Electrodes are provided on two opposite flat sides of the sensor strip or multiple sensor strips, with the sensor strip and the electrodes provided thereon forming at least one sensor. This sensor is then similar to the one formed by the aforementioned sensor strip, in particular it is exactly identical in construction. In this way, it can be sealed twice, so to speak, and a load or deformation of the sensor or the sensor strip can be detected.

It is possible to arrange the seal in or on a vertical sealing gap. The seal can either be arranged in a concealed form at the end or exit of the sealing gap to the outside, or the seal is flat or in the form of strips and is arranged flat on edge. It is advantageously arranged on edge flat on the hob.

In an embodiment of the invention, a sensor can be formed by an individual sensor strip or by part of a sensor strip or part of a length of a sensor strip and at least two electrically contacted electrodes. As will be explained in more detail below, a sensor can be formed differently by a different arrangement of the electrodes and also by their electrical contacting and evaluation. The sensors are advantageously all of the same type, in particular of an identical type, on a sensor strip educated. The functional mechanisms can have a change in capacitance or a change in electrical resistance. This is explained in more detail below. In the case of separate sensors that are separate from one another, it is preferable for these to all be of identical design.

An electrode can be a conductive coating on the underside of the hob plate or directly on the sensor strip, for example a conductive layer of metal or graphite or carbonaceous material, preferably a printed layer. Alternatively, an electrode can be formed by a film or an adhesive film made of electrically conductive material, which is then attached to the sensor strip or to the hob plate or to a frame part or the like. is attached.

In an advantageous embodiment of the invention, the sensor strip can be flat and the planes of the upper side and the lower side of the sensor strip can be parallel to one another. It can advantageously have a rectangular or trapezoidal cross section. It preferably has a cross section that remains the same over its length; all sensor strips are particularly preferably the same or have an identical cross section. An upper side and an opposite lower side of the sensor strip can advantageously be parallel to one another, with the distance between these two sides being or forming the height of the sensor strip. The electrodes are particularly advantageously arranged on these two opposite sides. It can be provided that there are no electrodes on the intervening sides, which can also be regarded as side edges or lateral surfaces, and in particular that the electrodes arranged on the other sides do not overlap on them.

In a further embodiment of the invention, the sensors or at least sensor strips can be provided along at least 90% of the circumference around the hob plate or the circumference of the hob. Advantageously, sensor strips can be provided without interruption or continuously along 100%, so that they optimally fulfill a sealing effect mentioned at the outset for the hob, in particular when it is arranged on an aforementioned worktop. In a first alternative embodiment, it is possible for a continuous and/or a part or one-piece sensor strip to be provided at least along one side of the hob or hob plate, preferably running along all four sides. In corner areas of the hob or the hob plate, two separate sensor strips, each of which runs along one of the sides, can advantageously abut at the ends without being formed in one piece and in one continuous piece. In doing so, they abut one another in such a way that they lie tightly against one another. You can even be permanently connected to each other, for example glued or welded. Then there is also a sealing effect in the corner areas.

In a second alternative embodiment, a number of individual and separate sensor strips are arranged one behind the other along each side. A distance between two adjacent sensor strips or sensor strips arranged one behind the other can be a maximum of 20 mm, preferably a maximum of 5 mm. It can be at least 0.1 mm or 0.5 mm to 4 mm. A distance is therefore desired here, which can be advantageous or even necessary, for example, in the case of an embodiment of the sensor strips with electrical conductivity corresponding to an FSR sensor described below. Then there is a sufficiently good separation of the sensor signals from neighboring sensors and the sensors themselves.

In one embodiment of the invention, the sensor strip can have or consist of an elastic polymer. In particular, it can consist of an electroactive polymer or of a dielectric polymer. It is then particularly possible, but not mandatory, for the electrodes to be in the form of capacitor plates and thus form a capacitive sensor or capacitor as a sensor. The distance between the capacitor plates is determined by the sensor strip in between, with a variable height depending on the weight load on the hob plate. The sensors have a variable capacitance between the electrodes that is dependent on the weight load on the hob plate. This sensor is evaluated by the cooktop control as a capacity or as a capacitor.

In an alternative embodiment of the invention, the sensor strip has or consists of an elastic polymer. This can have a pressure-dependent electrical resistance, in particular consist of a material corresponding to an FSR sensor. The sensors can then be designed as FSR sensors, in particular by the sensor strips being made of such FSR material. In this case, the sensors have a variable electrical resistance dependent on a weight load on the hob plate. This electrical resistance can be evaluated by the hob controller in a manner similar to that described above for capacitance sensors, so that it can determine the level of the weight load and the location of the weight load on the hob plate.

In an arrangement according to the invention of a hob as described above on a worktop, the hob is fastened to it, with an underside of the sensor strip preferably resting in the vertical direction on the worktop by means of at least one intermediate frame part. Alternatively, it rests on a support profile attached to the worktop and is carried by it. In a development of such an arrangement according to the invention, a gap is provided between the hob or the hob plate on the one hand and the worktop or a frame part arranged thereon on the other hand. The sensor strip is arranged in this gap, the additional seal according to the invention being arranged outwardly in the gap or outside at an exit of the gap.

In an advantageous embodiment, a circumferential depression can be provided in the edge region of the hob plate in the top of the worktop. A cutout in the worktop for the hob or an inner housing on the underside is particularly advantageously provided within the recess, it being possible for the at least one frame part or the support profile to be arranged in this recess. By means of this recess, the hob can be arranged sunk in the worktop.

In an advantageous development of the invention, the sensor strip can seal the hob from the outside in relation to the worktop, in particular in a liquid-tight manner. This allows the hob to move relative to the worktop, while at the same time ensuring that the gap that is required for mobility is sealed. So no other measures are necessary.

In a method according to the invention for detecting a weight load on a previously described capacitive properties or resistive properties of the sensors, which are dependent on a weight load on the hob plate, are measured by means of several sensors. The hob controller can determine the weight load on the hob plate from the signals from these sensors, in particular the location of the weight load on the hob plate. This is independent of the type of sensors.

In a further embodiment of the method according to the invention, the capacitive properties or resistive properties of the sensors of the additional sensor strip described above, which are dependent on a load on this sensor strip or on these sensors, can also be measured. The hob control can use the signals from these additional sensors to determine the load on it or on the sensor strip. This load can be detected in addition to the above-described detection of the weight load on the hob plate and increase the accuracy of the weight load detection. Alternatively, other values can be recorded with these additional sensors, for example a lateral expansion of the hob or the hob plate due to high temperatures or the like. In addition to the claims, these and other features are also apparent from the description and drawings, with the individual features being implemented individually or in multiples in the form of sub-combinations in one embodiment of the invention and in other areas and are advantageous as well as in themselves protectable versions for which protection is claimed here. The subdivision of the application into individual sections and subheadings does not limit the general validity of the statements made thereunder.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages and aspects of the invention result from the claims and from the description of exemplary embodiments of the invention, which are explained below with reference to the figures. show:

Fig. 1 is a plan view of a hob according to the invention in an arrangement according to the invention on a worktop,

Fig. 2 is a sectional view of the arrangement of Fig. 1 along an outer edge of the hob with sensors of a first type and additional sensors as an additional seal, Fig. 3 is a right-angled section through the sensors of the first type of Fig. 2, which are formed with a continuous sensor strip and electrodes in a gap between the hob plate and the frame part on the worktop,

4 shows a sectional view similar to FIG. 3 through a second type of sensor, which is formed by differently designed electrodes on a sensor strip,

5 shows a further sectional view similar to FIG. 2 with a different arrangement of the hob on the worktop with a sealing lip requested by the sensor strip,

Fig. 6 shows an enlargement of the area with the sealing lip from Fig. 5

7 shows yet another sectional view similar to FIG. 2 with yet another modification of the arrangement of the hob on the worktop; and FIG. 8 shows yet another sectional view similar to FIG. 2 with yet another modification of the arrangement of the hob on the worktop.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

1 shows a plan view of a hob 11a according to the invention in a first embodiment of the invention. The hob 11a has a rectangular hob plate 12a, which is advantageously made of glass ceramic. The hob plate 12a has an upper side 13a and an underside which will be explained later. It has an edge area along its four sides 15a, for example the outer 2 cm to 5 cm. It also has a peripheral outer edge 16a, which is formed, so to speak, by an outer edge with a width corresponding to the thickness of the hob plate 12a. For this purpose, reference is also made to the sectional view of FIG. The hob 11a is arranged on a worktop 35a and forms with it an arrangement 9a according to the invention.

The hob 11a has under the hob plate 12a four heating devices 18a, which are shown in dashed lines. Any heating devices can be used, but induction heating coils or radiant heating devices are advantageous. A pot T is shown on the left-hand side of the heating device 18a, the weight and position of which can be detected using the invention. At the front in the central area, the hob 11a has an operating device 19a and a hob controller 20a. This cooktop controller 20a takes over all the control functions and evaluation functions on the cooktop 11a, also for detecting the weight load.

In FIG. 2 it can be seen from the arrangement 9a that an inner housing 22a is arranged on an underside 14a of the hob plate 12a and is advantageously fastened to it in a known manner. The inner housing 22a contains, for example, the hob control 20a and also covers the heating devices 18a. In the edge region 15a of the hob plate 12a, the hob 11a has a sensor strip 26a flush on the outside on its underside 14a, on which sensors 25a are formed. This is explained in more detail below starting with FIG. With this sensor strip 26a, the hob 11a rests on a horizontal section of a frame part 32a and is, so to speak, carried by it. The frame part 32a has on the left a leg 32'a which projects vertically upwards and on the right on the horizontal section has a leg 32''a which points vertically downwards. It is arranged in a recess 40a near an inner edge 39a of a cutout 38a of a worktop 35a, advantageously firmly arranged. For example, it can be glued to the left vertical leg 32'a by means of an adhesive 31a, for example by means of silicone adhesive. Such an adhesive bond can possibly also be provided on the entire frame part 32a, ie possibly also on the right-hand vertical leg 32''a. The frame part 32a is advantageously made of aluminum or stainless steel. The vertical leg 32'a does not extend upwards above the level of the upper side 36a of the worktop 35a, and the bond 31a does not, if possible, either. But both like it. 1 visible.

There is a certain degree of vertical mobility between the hob plate 12a and the frame part 32a, which is to be regarded, so to speak, as an integral part of the worktop 35a. In this way, the hob 11a together with the hob plate 12a can move vertically in relation to the worktop 35a, thereby compressing the sensor strip 26a. This can be recorded and from this the weight load can be determined according to height and location. For this vertical mobility, an intermediate gap 30a is provided, which not only runs in the area of the sensor strip 26a, but also continues outwards or upwards. An additional sensor strip 126 is provided as a seal in order to seal the gap 30a here at the top, where liquid could be present, and not only at the sensor strip 26 . The sensor strip 126 is advantageously designed in exactly the same way as the sensor strip 26 and can also form corresponding sensors 125a, but does not have to. In this way, for example, forces could be detected in the horizontal direction, which act on the sensor strip 126a or the sensors 125a formed thereby. Alternatively, the sensor strip 126a to the left of the vertical leg 32'a of the frame part 32a and to the right of the outer edge 16a of the hob plate 12a can lie firmly; it can be glued to this or at least exhibit significant friction. As a result of the vertical movement when there is a change in a weight load, there is a significant change in a mechanical load on the sensor strip 126a, which can be detected using signals and can be evaluated accordingly. For example, the vertically extending sensor strip 126 could be subjected to a certain shearing load when the hob plate 12a moves relative to the worktop 35a downwards, which could be detected, for example if the sensors 125a are designed as the aforementioned FSR sensors.

An advantage of the arrangement of the sensor strips 126a at this point is the small distance to the horizontally running sensor strips 26a with the sensors 25a. Thus, by comparing the respective measured values, disruptive influences from the cooktop control 20a can be better calculated out.

2 it can be seen that the upper side 13a of the hob plate 12a runs approximately in the same plane as the upper side 36a of the worktop 35a.

Alternatively, the sensor strip 126a can also be used only as a seal without being evaluated as a sensor.

3 shows a sectional view at right angles through the gap 30b and thus through the hob plate 12a and the frame part 32a and the worktop 35a together with the sensor strip 26a. Electrodes 27a on the one hand and electrodes 28a on the other hand are arranged on both sides of the sensor strip 26a, advantageously non-detachably applied. They consist of electrically conductive material, for example as a coating of graphite or carbon-containing material, alternatively as an applied thin strip of metal or the like. This has been explained above. Its width advantageously corresponds approximately to the width of the sensor strip 26a. The electrodes 27a and 28a are each separated or spaced apart from one another by narrow gaps 29a. This is to ensure they don't interfere with each other. As explained at the outset, they are evaluated either capacitively or as capacitive sensors, ie by opposing electrodes 27a and 28a forming capacitors with the sensor strip 26a as a dielectric in between. Compression of the sensor strip 26a due to increasing weight loading causes the opposite electrodes 27a and 28a to move closer together with a corresponding increase in capacitance, which can be measured by the cooktop control 20a and evaluated accordingly.

Alternatively, the sensor strips 26a can be formed from a material that has a form-dependent electrical resistance, in particular corresponding to known FSR or force sensing resistor sensors or resistive sensors. The more the sensor strip 26a is compressed due to increasing weight, the lower the electrical resistance between the opposing electrodes 27a and 28a. The cooktop control 20a can in turn evaluate this accordingly and recognize it as a weight load.

In the case of a hob 11a according to FIG. 1, eight sensors 25a, for example, are provided around the hob plate 12a, each of which is elongate. There can be two sensors in a row on the short sides and three on the long sides. Correspondingly, more sensors could also be provided, alternatively fewer.

4 shows a modification of an arrangement 9b of a hob 11b. A gap 30b is formed between the hob plate 12b itself and a frame part 32b which is arranged on the worktop 35b or is supported thereon. A continuous sensor strip 26b runs in this gap 30b. A continuous upper electrode 27b is provided on its upper side towards the hob plate 12b. Three electrodes 28b spaced apart from one another by gaps 29b are provided on the underside towards the frame part 32b. Similar to the embodiment in FIG. 3, these three electrodes 28b could each form three capacitors as capacitive sensors directly with the upper opposite electrode 27b. This would then be similar to Fig. 3.

Alternatively, in order to be able to save on electrical contacting to the upper electrode 27b, it is possible for a capacitance to be measured in each case between two adjacent lower electrodes 28b. These capacitances go, so to speak, from the lower electrode 28b through the sensor strip 26b to the upper electrode 27b and from there again through the Sensor strip 26b down to the adjacent bottom electrode 28b. So this is a series connection of two capacitors, and when the weight load increases, each of the two capacitances increases, which in turn can be measured. It is also possible in the arrangement 9b of FIG. 4 to use resistive sensors, as explained above, instead of capacitive sensors 25b.

If the frame part 32b consists of metal, the arrangement of the sensor strip 26b can also be reversed, so that the electrodes 28a are arranged at the top. The continuous electrode without an electrical connection can then be formed below or below the sensor strip 26b by the electrically conductive frame part 32b itself. That saves even more effort.

In a further arrangement 9c according to the invention of a hob 11c on a worktop 35c according to FIG. 5, the outer edge 16c of the hob plate 12c is exposed in the edge region 15c. The hob plate 12c thus runs well above the top 36c of the worktop 35c, even its underside 14c. The worktop 35c has a cutout 38c including an inner edge 39c, but no depression or the like. as in FIG. 2. The inner housing 22c on the underside 14c of the hob plate 12c contains a heating device 18c. It is not permanently connected to the hob plate 12c. In the left area, the inner housing 22c extends with an extension 22'c which overlaps 1 cm or 2 cm on the top 36c of the worktop 35c. Thus, the inner housing 22c rests on the worktop 35c by means of the extension 22'c and cannot be moved in the vertical direction.

Here, the hob plate 12c can be moved vertically on the one hand in relation to the worktop 35c and on the other hand in particular also in relation to the inner housing 22c. For this purpose, a gap 30c is formed between the two, in which a sensor strip 26c is arranged on the underside 14c of the worktop 12c. According to FIGS. 3 and 4, this forms sensors 25c for detecting a weight load. The sensor strip 26c thus already at least partially seals the gap 30c and thus also the hob 11c overall relative to the worktop 35c.

According to the invention, a sealing lip 42c is formed on the sensor strip 26c for a further improved sealing effect, also in order to cover the sensor strip 26c to the outside as far as possible and to protect it from external influences. This sealing lip 42c is advantageously formed in an injection molding process. It can either be made of a different material, and a two-component injection molding process is used. The properties for the sealing lip 42c can then be selected precisely, independently of the function of the sensor strip 26c and possible material specifications or restrictions therefrom. Alternatively For example, the sealing lip 42c can be formed from the same material as the sensor strip 26c in a single step. If this material is sufficiently elastic, a sufficiently good sealing effect with sufficient elasticity can also be created. The sealing lip 42 runs beveled at an angle of about 60° from the top 36c to the outer edge 16c.

The enlargement of the illustration in FIG. 6 shows that the sealing lip 42c again seals and closes the gap 30c very well towards the outside. Furthermore, the sensor strip 26c or the sensors 25c and thus also their electrodes are well protected against harmful external influences, in particular due to moisture.

The sealing lip 42c has a substantially triangular cross-section and rests with one side firmly and above all in a sealing manner on the upper side 36c of the worktop 35c. The left end of the extension 22'c of the inner housing 22c is thereby covered. The tip of this upright triangle protrudes slightly above the sensor strip 26c and runs in the lowest area along the outer edge 16c of the hob plate. This also provides good protection against the ingress of liquid from above.

In a further alternative embodiment of the invention, the sealing lip 42c can be designed or raised so far, preferably with a continuous sloping outer side, that it covers or covers the entire outer edge 16c of the hob plate 12c. This means that it does not need to be ground in a complex manner, and injuries to a user can also be prevented. Finally, the hob 11c can make an outwardly closed and visually appealing impression.

In a further arrangement 9d according to the invention of a hob 11d on a worktop 35d according to FIG The embodiment of FIG. 5. The outer edge 16d of the hob plate 12d in turn encompasses an angled profile 23d with tongues at the top and bottom, which clamp the hob plate 12d. A bevel 24d on the angle profile 23d has an angle of 55° to the horizontal. A sensor strip 26d is arranged on the bevel 24d, which is designed similarly to the sensor strip 26c of FIG. 5. However, a sealing lip 42d is designed somewhat differently at the end of the sensor strip 26d. Although it is also widened, it completely closes off a recess on the left-hand edge of the angle profile 23d. In this case, the sealing lip 42d is, so to speak, fitted into the outer contour of the angle profile 23d. In any case, it also closes tightly. The tightness of the hob 11 d in the arrangement 9d on the worktop 35d is not dependent on the worktop 35d itself, but is provided, so to speak, in the structural unit of the hob 11d itself. The hob 11d can thus also be easily replaced in a modular manner. This is similar to that in Fig. 5.

An underside of the sensor strip 26d lies flat against a frame section 22"d, which runs obliquely and, in particular, is parallel to the underside of the angle profile 23d. The frame section 22"d transitions into an extension 22'd of the inner housing 22d, as previously described. Similar to the embodiment of FIG. 5, the hob plate 12d can be moved vertically relative to the inner housing 22d in order to be able to detect a weight load on the hob plate 12d or changes thereto. Internal mobility is necessary in the hob 11d, so to speak, ie of the hob plate 12d relative to the inner housing 22d.

A gap 30d is formed between the angle profile 23d and the frame section 22'dc. This gap 30d is closed by the sensor strip 26d or by the sensors 25d formed thereby, on the one hand, and outwards by the sealing lip 42d, on the other hand.

FIG. 8 shows yet another embodiment of a hob 11e in an arrangement 9e on a worktop 35e. The hob 11e has a hob plate 12e with a top 13e and a bottom 14e, with a conventional and previously described inner housing 22e being attached to this bottom 14e. Hob plate 12e and inner housing 22e bil here similar to Fig. 1 a fixed and inherently immovable unit. In an edge area 15e of the hob plate 12e with the outer edge 16e, an angular profile 23e is provided, in particular glued. The angular profile 23e consists essentially of a trapezoidal main part, from which an extension 23'e branches off horizontally from below to the right. It rests against the underside 14e of the hob plate 12e and can advantageously be glued in place here, possibly even at the top on the outer edge 16e. The angular profile 23e advantageously consists of aluminum or stainless steel. A sensor strip 26e is arranged on its underside, for example glued in place, which forms a plurality of sensors 25e. The hob 11e thus rests on a right-hand horizontal leg 32"e of a frame part 32e. A central portion of this frame portion 32e extends vertically in the upper portion along the inner edge 39e of the cutout 38e. A horizontal section 32'e of the frame part 32e overlaps to the left on an upper side 36e of the worktop 35e. It is advantageously glued to the top 36e of the hob plate 35e. A gap 30e is formed between them for vertical mobility of the hob 11e and thus of the angle profile 23e in comparison to the worktop 35e or to the frame part 32e attached thereto. This is essentially closed or sealed by the sensor strip 26e or the sensors 25e formed thereby. On the one hand, this may not always be tight. On the other hand, harmful or damaging substances can reach the sensor strips 26e from the outside and thus impair their function.

Since the gap 30e runs so deep here and since it is obvious that this gap must be open at the top, a sealing profile 44e is additionally provided in this FIG. 8, for example made of metal. It has a sloping underside that is exactly parallel to the bevel 24e of the angle profile 23e. The upper side, which runs flat or horizontally, has short, chamfered overhangs to the left and right. In this regard, reference is made to the previously explained FIG. 7, where something similar is disclosed in the case of the angular profile 23d to the right.

So if the frame part 32e is firmly and tightly glued to the worktop 35e, and the angular profile 23e to the hob plate 12e in a similar form, the two parts move vertically relative to one another. From the special shape of FIG. 8 it can be seen that an even better sealing of the gap 30e is achieved with the sealing profile 44e, especially with the extension 44'e projecting downwards. Essentially, a type of labyrinth seal is also achieved here, since the sealing profile 44e can move somewhat with it, particularly in the case of vertical movement, without the need for further measures.

Claims

patent claims

1. Hob with: a hob plate, which has an outer peripheral edge area and an outer edge, at least one heating device under the hob plate,

Sensors for detecting a weight load on the hob plate, a hob controller which is connected to the sensors and is designed to evaluate and record the weight load, with at least three sensors being provided in the edge area of the hob plate, characterized in that in the edge area of the hob plate and at least along of 90% along a circumference around the hob plate at least one flat sensor strip made of elastic material is provided, preferably several sensor strips are provided, the length of the at least one sensor strip is at least 5 times as large as its width, and its width is at least 2 times as large as its height, electrodes are provided on two opposite flat sides of the sensor strip or the plurality of sensor strips, in particular elongated electrodes with a longitudinal direction parallel to the longitudinal direction of the sensor strip, the sensor strip and the electrodes provided thereon at least ns form a sen sor, the sensors are elongate along the circumference around the hob plate, a circumferential seal is provided which has a maximum distance of 10 mm from the sensor strip, the seal being designed to seal the hob from the outside, in particular seal liquid-tight.

2. Hob according to claim 1, characterized in that the seal is formed on the sensor strip or is connected and formed in one piece with it, in particular is formed on the outside of the sensor strip, the seal preferably being made of the same material as the sensor strip, wherein In particular, the seal has a larger or thicker cross-section than the sensor strip, with an intermediate region without electrodes preferably being provided between the seal and the sensor strip.

3. Hob according to claim 1, characterized in that the seal is formed separately from the sensor strip, the seal preferably being made of a material other than the sensor strip, in particular silicone or rubber.

4. Hob according to claim 1, characterized in that the seal is formed separately from the sensor strip, the seal is formed flat, the seal consists of the same material as the sensor strip, on two opposite flat sides of the sensor strip or more

Sensor strip electrodes are provided, the sensor strip and the electrodes provided thereon form at least one sen sor.

5. Hob according to claim 3 or 4, characterized in that the seal is arranged in or on a vertical sealing gap, the seal preferably being flat, in particular having a strip shape, and being arranged flat on edge on the hob.

6. Hob according to one of the preceding claims, characterized in that a sensor is formed by a single sensor strip or by part of a length of a sensor strip and at least two electrically contacted electrodes thereon.

7. Hob according to one of the preceding claims, characterized in that the sensor strip is flat and has a rectangular or trapezoidal cross section, in particular has a constant cross section over its length, with preferably an upper side and an opposite lower side of the sensor strip being parallel to one another, wherein the elec trodes are arranged on these two opposite sides.

8. Hob according to one of the preceding claims, characterized in that the sensors or at least the sensor strips are provided without interruption or continuously along 100% along the circumference around the hob plate.

9. Hob according to one of the preceding claims, characterized in that at least along one side of the hob or the hob plate a continuous and/or one-piece or one-piece sensor strip is provided, preferred wise along all four sides, with two separate sensor strips, each running along one of the sides, abutting one another in particular in the corner areas of the hob or the hob plate without being formed in one piece and in one continuous piece.

10. Hob according to claim 9, characterized in that several individual and separate sensor strips are arranged one behind the other along each side, the distance between two adjacent or one behind the other sensor strips preferably being a maximum of 20 mm, preferably a maximum of 5 mm.

11. Hob according to one of the preceding claims, characterized in that the height of the sensor strip or all sensor strips is from 1 mm to 10 mm, preferably from 2 mm to 5 mm.

12. Hob according to one of the preceding claims, characterized in that the sensor strip has or consists of an elastic polymer, in particular an electroactive polymer or a dielectric polymer.

13. Hob according to one of the preceding claims, characterized in that the electrodes are designed as capacitor plates of a capacitive sensor or a sensor as a capacitor and are evaluated by the hob controller as a capacitor, with the distance between the capacitor plates being determined by the sensor strips lying in between with a variable height depending on a weight load on the hob plate, the sensors preferably having a variable capacitance between the electrodes which is dependent on the weight load on the hob plate.

14. Hob according to one of Claims 1 to 12, characterized in that the sensor strip has or consists of an elastic polymer which has a pressure-dependent electrical resistance, in particular made of a material corresponding to an FSR sensor.

15. Hob according to one of claims 1 to 12 or 14, characterized in that the sensors are designed as FSR sensors, in particular in that the sensor strips are made of FSR material according to claim 14, the sensors preferably being subject to a weight load have variable electrical resistance dependent on the hob plate.

16. Arrangement of a hob according to one of the preceding claims on a worktop, characterized in that the hob is attached to the worktop, with an underside of the sensor strip preferably resting in the vertical direction by means of at least one intermediate frame part on the worktop or on one on the worktop attached support profile rests and is carried by it.

17. Arrangement according to claim 16, characterized in that a gap is provided between the hob or the hob plate and the worktop, the sensor strip being arranged in the gap and the seal arranged in the gap or outside at an exit of the gap to the outside is.

18. Arrangement according to claim 16 or 17, characterized in that in the upper side of the worktop there is a circumferential recess in the edge region of the hob plate, with a cutout in the worktop for the hob preferably being provided within the recess, with the recess the at least one frame part or the support profile are arranged.

19. Method for detecting a weight load on a hob according to one of claims 1 to 15, characterized in that the capacitive properties or resistive properties of the sensors, which are dependent on a weight load on the hob plate, are measured using a plurality of sensors and the hob controller from the signals from these sensors, the weight load on the hob plate is determined, in particular the location of the weight load on the hob plate is determined.

20. The method according to claim 19, characterized in that the capacitive properties or resistive properties of the sensors of the additional sensor strip according to claim 4, which are dependent on a load on the sensor strip, are measured by means of a plurality of sensors and the cooktop control from the signals from these sensors determines the load on the sensor strip.