CA2291381A1 - An electric hob - Google Patents
An electric hob Download PDFInfo
- Publication number
- CA2291381A1 CA2291381A1 CA002291381A CA2291381A CA2291381A1 CA 2291381 A1 CA2291381 A1 CA 2291381A1 CA 002291381 A CA002291381 A CA 002291381A CA 2291381 A CA2291381 A CA 2291381A CA 2291381 A1 CA2291381 A1 CA 2291381A1
- Authority
- CA
- Canada
- Prior art keywords
- hob
- heating conductor
- plate
- accordance
- lead
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 238000010438 heat treatment Methods 0.000 claims abstract description 62
- 239000004020 conductor Substances 0.000 claims abstract description 47
- 239000000919 ceramic Substances 0.000 claims abstract description 17
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 9
- 229910052802 copper Inorganic materials 0.000 claims description 9
- 239000010949 copper Substances 0.000 claims description 9
- 229910052751 metal Inorganic materials 0.000 claims description 5
- 239000002184 metal Substances 0.000 claims description 5
- 229910052581 Si3N4 Inorganic materials 0.000 claims description 4
- 239000011888 foil Substances 0.000 claims description 4
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 claims description 4
- 229910010271 silicon carbide Inorganic materials 0.000 claims description 4
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 claims description 4
- 229910017083 AlN Inorganic materials 0.000 claims description 2
- PIGFYZPCRLYGLF-UHFFFAOYSA-N Aluminum nitride Chemical compound [Al]#N PIGFYZPCRLYGLF-UHFFFAOYSA-N 0.000 claims description 2
- 239000003795 chemical substances by application Substances 0.000 claims description 2
- 230000001105 regulatory effect Effects 0.000 claims 1
- 239000010408 film Substances 0.000 description 10
- PNEYBMLMFCGWSK-UHFFFAOYSA-N Alumina Chemical compound [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 6
- 230000005540 biological transmission Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000000615 nonconductor Substances 0.000 description 2
- 238000013021 overheating Methods 0.000 description 2
- 239000006244 Medium Thermal Substances 0.000 description 1
- 238000010285 flame spraying Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 239000012774 insulation material Substances 0.000 description 1
- 150000004767 nitrides Chemical class 0.000 description 1
- 229920001296 polysiloxane Polymers 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B3/00—Ohmic-resistance heating
- H05B3/68—Heating arrangements specially adapted for cooking plates or analogous hot-plates
- H05B3/74—Non-metallic plates, e.g. vitroceramic, ceramic or glassceramic hobs, also including power or control circuits
- H05B3/748—Resistive heating elements, i.e. heating elements exposed to the air, e.g. coil wire heater
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B3/00—Ohmic-resistance heating
- H05B3/68—Heating arrangements specially adapted for cooking plates or analogous hot-plates
- H05B3/74—Non-metallic plates, e.g. vitroceramic, ceramic or glassceramic hobs, also including power or control circuits
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Resistance Heating (AREA)
- Surface Heating Bodies (AREA)
- Central Heating Systems (AREA)
Abstract
The invention relates to an electric hob for the low-voltage range having a hob plate made of heavy duty ceramics and having a heating conductor which forms a large-area contact with the lower side of the hob plate. To ensure that the electrical supply leads do not heat up excessively due to the high currents in the low-voltage range, in each case at least one lead element is interposed between the heating conductor and the electrical supply leads which possesses a resistance value lying between the resistance values of the heating conductor and the relevant electrical supply lead.
Description
An electric hob The invention relates to an electric hob for the low-voltage range having a hob plate made of heavy duty ceramics and having a heating conductor which forms a large-area contact with the lower side of the hob plate.
Such a hob for conventional home voltages of 1 lOV to 220V is known from DE
02 813 U 1. In particular, silicone nitride or silicon carbide is named as the heavy duty ceramics for the hob plate. For lower temperatures in the range of 250°C, other electrically insulating ceramics such as aluminium oxide may also be used.
Such heavy duty ceramics are particularly suitable for use as hob plates thanks to their thermal conductivity, their thermal coefficient of expansion, their permitted surface strain and their specific electric resistance. The thermal conductivity of these materials is in the medium range between 5-40W/mK. It was found that with such medium thermal conductivity values a good compromise can be reached between the thermal insulation towards the housing and the thermal transmission towards the heating elements. At the same time, the thermal coefficient of expansion of such heavy duty ceramics is very low being in the range of 10-6 1/K so that the strains and warpage of the hob plate caused by different heating remain low. The installed power per unit
Such a hob for conventional home voltages of 1 lOV to 220V is known from DE
02 813 U 1. In particular, silicone nitride or silicon carbide is named as the heavy duty ceramics for the hob plate. For lower temperatures in the range of 250°C, other electrically insulating ceramics such as aluminium oxide may also be used.
Such heavy duty ceramics are particularly suitable for use as hob plates thanks to their thermal conductivity, their thermal coefficient of expansion, their permitted surface strain and their specific electric resistance. The thermal conductivity of these materials is in the medium range between 5-40W/mK. It was found that with such medium thermal conductivity values a good compromise can be reached between the thermal insulation towards the housing and the thermal transmission towards the heating elements. At the same time, the thermal coefficient of expansion of such heavy duty ceramics is very low being in the range of 10-6 1/K so that the strains and warpage of the hob plate caused by different heating remain low. The installed power per unit
-2-area of heavy duty ceramics here can be in the range of other heavy duty hob plates between 4 and 16 W/cm2. The specific electric resistance of some heavy duty ceramics is in the range of 10'3 ohm/cm and is thus so high that corresponding electrical heating conductors can be affixed directly to the lower side of the hob plate.
If such electric hobs are to be designed for the low-voltage range, special problems arise in the electrical supply as very high currents are required to obtain the same heating power as in the domestic area. If the hob is to be designed for example for a 12V car battery, currents of around 80A flow in the leads while in the domestic area only currents of a few amperes occur. The high currents can lead to the electrical supply leads heating up in an unwanted manner. If, on the other hand, the resistance of the electrical supply leads is kept particularly low, these will as a rule also possess good thermal conductivity so that in turn there is a risk of the heat being passed through in an unwanted manner from the hob plate to the electrical supply leads.
It is therefore the object of the invention to provide an electric hob for the low-voltage range where it is insured that the electrical supply leads do not heat up excessively.
The solution in accordance with the invention comprises there being interposed in each case between the heating conductor and the electrical supply leads at least one lead element possessing a resistance value lying between the resistance values of the heating conductor and of the relevant electrical supply lead.
Thus in its broadest embodiment this invention seeks to provide an electric hob for the low-voltage range having a hob plate made of heavy duty ceramics; and having a heating conductor forming a large-area contract with the lower side of the hob plate, wherein in each case there is interposed between the heating conductor and the electrical supply leads at least one lead element possessing a resistance value lying between the resistance values of the heating conductor and the relevant supply lead.
The invention is based on the finding that the interposition of a further lead element between the heating conductor and the relevant elech~ical supply lead, a compromise can be found between the heat transmission from the heating conductor and the heating up of the relevant lead element. If an electrical supply lead is connected directly to the heating conductor, there is no need to fear the heating up of the supply lead due to the high currents; however, a heating up of the heating _3_ conductor does occur due to the good thermal conductivity of the electrical supply lead. If, in contrast, a lead element is interposed in accordance with the invention between the heating conductor and the relevant electrical supply lead, such lead element having a resistance value being between the resistance values of the heating conductor and the relevant electrical supply lead, then both the heat transmission through the lead element to the heating conductor and the heating up of the lead element due to the high currents can be held in limits.
In accordance with a preferred embodiment it is provided that the lead element consists of a piece of the heating conductor which is led away from the lower side of the hob plate and which possesses a greater cross-section than the heating conductor in large-area contact with the hob plate. In this way it is ensured that no additional contact resistance occurs between the lead element and the heating conductor.
At the same time, a particularly low-cost design of the lead element is possible as the lead element can be formed from the material of the heating conductor which is anyway already available: It has been shown here that any excessive heating of the lead element can already be avoided if the cross-section of the lead element is four times that of the heating conductor in large-area contact with the hob plate.
Another problem is the connection of the lead element to the relevant electrical supply lead, as it has to be prevented that the contact resistance between the lead element and the supply lead increases in such a way that an intolerably high heat-up is produced due to the high currents at the contact point. In accordance with a preferred embodiment it is provided that for the almost resistance-free connection between the at least one lead element and a supply lead, a copper block is provided on which the relevant lead ends are applied over the area. A large-area contact to the lead element or the relevant electrical supply lead can be made to the side surfaces of the copper block so that the contact resistance from the lead element to the copper block or from the supply lead to the copper block can be reduced to a minimum. Furthermore, the volume resistivity of the copper block is also extremely low so that any heating due to the connection between the lead element and the electrical supply line can be excluded.
In accordance with another preferred embodiment it is provided that the hob plate is made of silicon nitride of silicon carbide or of aluminium nitride . These ceramics possess the above-mentioned advantages of heavy duty ceramics.
With regard to the formation of the heating conductor, various designs can be considered. The design in accordance with the invention with the interposed lead element is particularly simple if the heating conductor consists of a metal foil pressed onto the lower side of the hob plate by means of an insulating film. A meander-like shape of the heating conductor can be formed here by the heating conductor being cut out of a metal foil using a suitable cutting device, for example using a laser.cutting device. The corresponding lead element for the supply to the heating conductor can here be cut out in one and the same process.
Further possibilities for the formation of the heating conductor consist of applying resistance films to the lower side of the hob plate in thick film technology or thin film technology. Furthermore, flame spraying processes can also be used with which an intermediate film of a material serving as an adhesion agent andlor an electrical insulator can be applied. For example, aluminium oxide can be sprayed on as an electrical insulator, this being particularly necessary if electrically conducting heavy duty ceramics such as silicon carbide are used.
Another possibility consists of affixing the heating conductor to the lower side of the hob plate in the form of a resistance paste. Here, resistance pastes or heating resistances with so-called PTC characteristics, that is with especially positive temperature characteristics of their resistance, are particularly suitable.
The PTC
characteristics lead to the resistance of the relevant heating resistor increasing suddenly when a certain temperature is reached so that in this range the temperature or -S-the power implemented in the heating resistor remains constant. Preferably, the corresponding jump temperature of the heating resistor is set here to the maximum temperature of the hob plate.
In accordance with another preferred embodiment an insulating film is provided which is pressed against the lower side of the hob plate by means of a press plate. In this way, the insulating film does not have to possess any mechanical stability of its own so that a variety of insulation materials can be used. To lead the lead element to the heating conductor located in the lower side of the hob plate, corresponding passages are provided in the insulating film and the press plate.
In accordance with another preferred embodiment temperature sensors can be provided in the form of resistance thermometers in direct contact with the ceramic plate in order to the regulate the temperature on the ceramic plate. In this way, an effective overheating protection can be additionally provided.
Further advantages and details of the invention are explained in more detail by means of an embodiment shown in the drawing. The drawing, which consists of one figure, shows a cross-section through the electric hob for the low-voltage range in accordance with the invention. The hob plate 1 of the hob consists of a round silicon nitride disc.
On the outside edge, the silicon nitride disc possesses a chamfer 10 which is pressed against a corresponding edge 11 of the housing wall 7. The hob plate 1 is here held by the press surface 4 which is supported on the housing floor 8 by a screw 9. An insulating layer 3 is located between the press plate 4 and the hob plate 1.
To heat the hob plate, a meander-like heating conductor in the form of a metal foil is introduced between the insulating film and the hob plate. For the power supply, passages 14, 15 are provided through the insulating film 3 and through the pass plate 4 in the middle and at the edge of the hob plate through which the lead ends 12, 13 of the heating conductor are passed. The ends 12, 13 here possess a cross-section four times that of the cross-sections of the heating conductor 2. On the free ends of the leads 12, 13, copper blocks 5, 6 are provided which create a contact connection between the leads 12, 13 and the electrical supply leads. To better illustrate the position of the press plate 4, the insulating film 3 and the heating conductor 2, the components in question are each shown with corresponding distances to one another, while in operation the individual components are naturally in a secure large-area contact to one another.
The electrical hob shown is preferably operated with a DC voltage of 12V and a current of 80A. The copper blocks 5, 6 ensure that the contact resistance between the electrical supply leads and the free ends of the leads 12, 13 can be neglected so that at this point no unwanted heating up can occur. The leads 12, 13 possess four times the cross-section of the actual heating conductor path 2 so that in relation to the same lead length in the leads only one quarter of the power is implemented over a heating conductor piece of the same length. In this way, it is ensured that the leads 12, 13 do not heat up in an unwanted manner. At the same time, however, the leads 12, 13 still possess a sufficiently high thermal resistance to prevent any overheating of the copper blocks 5, 6 or the electrical supply line by the heating conductor.
If such electric hobs are to be designed for the low-voltage range, special problems arise in the electrical supply as very high currents are required to obtain the same heating power as in the domestic area. If the hob is to be designed for example for a 12V car battery, currents of around 80A flow in the leads while in the domestic area only currents of a few amperes occur. The high currents can lead to the electrical supply leads heating up in an unwanted manner. If, on the other hand, the resistance of the electrical supply leads is kept particularly low, these will as a rule also possess good thermal conductivity so that in turn there is a risk of the heat being passed through in an unwanted manner from the hob plate to the electrical supply leads.
It is therefore the object of the invention to provide an electric hob for the low-voltage range where it is insured that the electrical supply leads do not heat up excessively.
The solution in accordance with the invention comprises there being interposed in each case between the heating conductor and the electrical supply leads at least one lead element possessing a resistance value lying between the resistance values of the heating conductor and of the relevant electrical supply lead.
Thus in its broadest embodiment this invention seeks to provide an electric hob for the low-voltage range having a hob plate made of heavy duty ceramics; and having a heating conductor forming a large-area contract with the lower side of the hob plate, wherein in each case there is interposed between the heating conductor and the electrical supply leads at least one lead element possessing a resistance value lying between the resistance values of the heating conductor and the relevant supply lead.
The invention is based on the finding that the interposition of a further lead element between the heating conductor and the relevant elech~ical supply lead, a compromise can be found between the heat transmission from the heating conductor and the heating up of the relevant lead element. If an electrical supply lead is connected directly to the heating conductor, there is no need to fear the heating up of the supply lead due to the high currents; however, a heating up of the heating _3_ conductor does occur due to the good thermal conductivity of the electrical supply lead. If, in contrast, a lead element is interposed in accordance with the invention between the heating conductor and the relevant electrical supply lead, such lead element having a resistance value being between the resistance values of the heating conductor and the relevant electrical supply lead, then both the heat transmission through the lead element to the heating conductor and the heating up of the lead element due to the high currents can be held in limits.
In accordance with a preferred embodiment it is provided that the lead element consists of a piece of the heating conductor which is led away from the lower side of the hob plate and which possesses a greater cross-section than the heating conductor in large-area contact with the hob plate. In this way it is ensured that no additional contact resistance occurs between the lead element and the heating conductor.
At the same time, a particularly low-cost design of the lead element is possible as the lead element can be formed from the material of the heating conductor which is anyway already available: It has been shown here that any excessive heating of the lead element can already be avoided if the cross-section of the lead element is four times that of the heating conductor in large-area contact with the hob plate.
Another problem is the connection of the lead element to the relevant electrical supply lead, as it has to be prevented that the contact resistance between the lead element and the supply lead increases in such a way that an intolerably high heat-up is produced due to the high currents at the contact point. In accordance with a preferred embodiment it is provided that for the almost resistance-free connection between the at least one lead element and a supply lead, a copper block is provided on which the relevant lead ends are applied over the area. A large-area contact to the lead element or the relevant electrical supply lead can be made to the side surfaces of the copper block so that the contact resistance from the lead element to the copper block or from the supply lead to the copper block can be reduced to a minimum. Furthermore, the volume resistivity of the copper block is also extremely low so that any heating due to the connection between the lead element and the electrical supply line can be excluded.
In accordance with another preferred embodiment it is provided that the hob plate is made of silicon nitride of silicon carbide or of aluminium nitride . These ceramics possess the above-mentioned advantages of heavy duty ceramics.
With regard to the formation of the heating conductor, various designs can be considered. The design in accordance with the invention with the interposed lead element is particularly simple if the heating conductor consists of a metal foil pressed onto the lower side of the hob plate by means of an insulating film. A meander-like shape of the heating conductor can be formed here by the heating conductor being cut out of a metal foil using a suitable cutting device, for example using a laser.cutting device. The corresponding lead element for the supply to the heating conductor can here be cut out in one and the same process.
Further possibilities for the formation of the heating conductor consist of applying resistance films to the lower side of the hob plate in thick film technology or thin film technology. Furthermore, flame spraying processes can also be used with which an intermediate film of a material serving as an adhesion agent andlor an electrical insulator can be applied. For example, aluminium oxide can be sprayed on as an electrical insulator, this being particularly necessary if electrically conducting heavy duty ceramics such as silicon carbide are used.
Another possibility consists of affixing the heating conductor to the lower side of the hob plate in the form of a resistance paste. Here, resistance pastes or heating resistances with so-called PTC characteristics, that is with especially positive temperature characteristics of their resistance, are particularly suitable.
The PTC
characteristics lead to the resistance of the relevant heating resistor increasing suddenly when a certain temperature is reached so that in this range the temperature or -S-the power implemented in the heating resistor remains constant. Preferably, the corresponding jump temperature of the heating resistor is set here to the maximum temperature of the hob plate.
In accordance with another preferred embodiment an insulating film is provided which is pressed against the lower side of the hob plate by means of a press plate. In this way, the insulating film does not have to possess any mechanical stability of its own so that a variety of insulation materials can be used. To lead the lead element to the heating conductor located in the lower side of the hob plate, corresponding passages are provided in the insulating film and the press plate.
In accordance with another preferred embodiment temperature sensors can be provided in the form of resistance thermometers in direct contact with the ceramic plate in order to the regulate the temperature on the ceramic plate. In this way, an effective overheating protection can be additionally provided.
Further advantages and details of the invention are explained in more detail by means of an embodiment shown in the drawing. The drawing, which consists of one figure, shows a cross-section through the electric hob for the low-voltage range in accordance with the invention. The hob plate 1 of the hob consists of a round silicon nitride disc.
On the outside edge, the silicon nitride disc possesses a chamfer 10 which is pressed against a corresponding edge 11 of the housing wall 7. The hob plate 1 is here held by the press surface 4 which is supported on the housing floor 8 by a screw 9. An insulating layer 3 is located between the press plate 4 and the hob plate 1.
To heat the hob plate, a meander-like heating conductor in the form of a metal foil is introduced between the insulating film and the hob plate. For the power supply, passages 14, 15 are provided through the insulating film 3 and through the pass plate 4 in the middle and at the edge of the hob plate through which the lead ends 12, 13 of the heating conductor are passed. The ends 12, 13 here possess a cross-section four times that of the cross-sections of the heating conductor 2. On the free ends of the leads 12, 13, copper blocks 5, 6 are provided which create a contact connection between the leads 12, 13 and the electrical supply leads. To better illustrate the position of the press plate 4, the insulating film 3 and the heating conductor 2, the components in question are each shown with corresponding distances to one another, while in operation the individual components are naturally in a secure large-area contact to one another.
The electrical hob shown is preferably operated with a DC voltage of 12V and a current of 80A. The copper blocks 5, 6 ensure that the contact resistance between the electrical supply leads and the free ends of the leads 12, 13 can be neglected so that at this point no unwanted heating up can occur. The leads 12, 13 possess four times the cross-section of the actual heating conductor path 2 so that in relation to the same lead length in the leads only one quarter of the power is implemented over a heating conductor piece of the same length. In this way, it is ensured that the leads 12, 13 do not heat up in an unwanted manner. At the same time, however, the leads 12, 13 still possess a sufficiently high thermal resistance to prevent any overheating of the copper blocks 5, 6 or the electrical supply line by the heating conductor.
Claims (11)
1. An electric hob for the low-voltage range having a hob plate made of heavy duty ceramics; and having a heating conductor forming a large-area contract with the lower side of the hob plate, wherein in each case there is interposed between the heating conductor and the electrical supply leads at least one lead element possessing a resistance value lying between the resistance values of the heating conductor and the relevant supply lead.
2. A hob in accordance with claim 1, wherein the lead element consists of a piece of the heating conductor which is led away from the lower side of the hob plate and which possesses a greater cross-section than the heating conductor in large-area contact with the hob plate.
3. A hob in accordance with claim 2, wherein the cross-section of the lead element is four times that of the heating conductor in large-area contact with the hob plate.
4. A hob in accordance with any of claims 1 to 3, wherein for the almost resistance-free connection between the at least one lead element and a supply lead a copper block is provided on which the relevant lead ends are affixed over the area.
5. A hob in accordance with any of claims 1 to 4, wherein the hob plate consists of silicon nitride of silicon carbide of aluminium nitride
6. A hob in accordance with any of claims 1 to 5, wherein the heating conductor consists of a metal film evaporated onto the lower side of the hob plate.
7. A hob in accordance with any of claims 1 to 5, wherein the heating conductor consists of a metal foil which is pressed onto the lower side of the hob plate by means of an insulating film.
8. A hob in accordance with any of claims 1 to 5, wherein the heating conductor consists of a resistance paste which is applied to the lower side of the hob plate directly or by means of an adhesion agent.
9. A hob in accordance with any of claims 1 to 8, wherein an insulating film is provided which is pressed against the lower side of the hob plate by means of a press plate.
10. A hob plate in accordance with claim 9, wherein passages are provided in the insulating film and the press plate through which the lead ends of the heating conductor are passed.
11. A hob plate in accordance with any of claims 1 to 10, wherein temperature sensors are provided in director contact with the ceramics plate which are connected to a regulating device for the regulation of the temperature at the ceramics plate.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19855481.8 | 1998-12-01 | ||
| DE19855481A DE19855481A1 (en) | 1998-12-01 | 1998-12-01 | Electric cooktop |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2291381A1 true CA2291381A1 (en) | 2000-06-01 |
Family
ID=7889669
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002291381A Abandoned CA2291381A1 (en) | 1998-12-01 | 1999-11-30 | An electric hob |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP1006755A3 (en) |
| JP (1) | JP2000188174A (en) |
| KR (1) | KR20000047736A (en) |
| AU (1) | AU5961999A (en) |
| CA (1) | CA2291381A1 (en) |
| DE (1) | DE19855481A1 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10059990A1 (en) * | 2000-12-02 | 2002-07-04 | Bosch Gmbh Robert | Ceramic heating module used as a cooking hob comprises an electrically insulating ceramic supporting plate and an electrically conducting hot conductor applied as a conducting layer on the plate |
| DE10112236C1 (en) * | 2001-03-06 | 2002-10-24 | Schott Glas | Ceramic hob |
| DE10112235C2 (en) * | 2001-03-06 | 2003-04-03 | Schott Glas | Ceramic hob |
| DE20117517U1 (en) | 2001-10-25 | 2002-02-21 | Rauschert Gmbh & Co Kg Paul | Mobile universal cooking device |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3105065A1 (en) * | 1981-02-12 | 1982-08-19 | Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt | Glass-ceramic hotplate |
| FR2623684A1 (en) * | 1987-11-24 | 1989-05-26 | Labo Electronique Physique | VITROCERAMIC HEATING ELEMENT |
| US5221829A (en) * | 1990-10-15 | 1993-06-22 | Shimon Yahav | Domestic cooking apparatus |
| DE29702813U1 (en) * | 1997-01-10 | 1997-05-22 | E.G.O. Elektro-Gerätebau Gmbh, 75038 Oberderdingen | Contact heat transferring cooking system with an electric hotplate |
| GB2322273B (en) * | 1997-02-17 | 2001-05-30 | Strix Ltd | Electric heaters |
-
1998
- 1998-12-01 DE DE19855481A patent/DE19855481A1/en not_active Withdrawn
-
1999
- 1999-11-16 EP EP99122793A patent/EP1006755A3/en not_active Withdrawn
- 1999-11-24 AU AU59619/99A patent/AU5961999A/en not_active Abandoned
- 1999-11-26 JP JP11335816A patent/JP2000188174A/en active Pending
- 1999-11-26 KR KR1019990052954A patent/KR20000047736A/en not_active Application Discontinuation
- 1999-11-30 CA CA002291381A patent/CA2291381A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| EP1006755A2 (en) | 2000-06-07 |
| AU5961999A (en) | 2001-06-21 |
| DE19855481A1 (en) | 2000-06-08 |
| KR20000047736A (en) | 2000-07-25 |
| EP1006755A3 (en) | 2002-01-23 |
| JP2000188174A (en) | 2000-07-04 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |