US3796850A - Pan detector for induction heating cooking unit - Google Patents

Pan detector for induction heating cooking unit Download PDF

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Publication number
US3796850A
US3796850A US00365671A US3796850DA US3796850A US 3796850 A US3796850 A US 3796850A US 00365671 A US00365671 A US 00365671A US 3796850D A US3796850D A US 3796850DA US 3796850 A US3796850 A US 3796850A
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United States
Prior art keywords
coil
cooking vessel
reed switch
magnetic
flux
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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.)
Expired - Lifetime
Application number
US00365671A
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English (en)
Inventor
W Moreland
R Mccoy
T Malarkey
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Westinghouse Electric Corp
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Westinghouse Electric Corp
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Publication date
Application filed by Westinghouse Electric Corp filed Critical Westinghouse Electric Corp
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Publication of US3796850A publication Critical patent/US3796850A/en
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    • 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
    • H05B6/00—Heating by electric, magnetic or electromagnetic fields
    • H05B6/02—Induction heating
    • H05B6/06—Control, e.g. of temperature, of power
    • H05B6/062—Control, e.g. of temperature, of power for cooking plates or the like
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24C—DOMESTIC STOVES OR RANGES ; DETAILS OF DOMESTIC STOVES OR RANGES, OF GENERAL APPLICATION
    • F24C15/00—Details
    • F24C15/10—Tops, e.g. hot plates; Rings
    • F24C15/102—Tops, e.g. hot plates; Rings electrically heated
    • F24C15/105—Constructive details concerning the regulation of the temperature
    • 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
    • H05B2213/00—Aspects relating both to resistive heating and to induction heating, covered by H05B3/00 and H05B6/00
    • H05B2213/05—Heating plates with pan detection means

Definitions

  • ABSTRACT [22] Filed: May 1973 A pan detection and control arrangement is provided [21 L N 365,671 for an induction heating cooking unit by providing a reed switch and a pair of permanent magnets disposed relative to the reed switch to hold the reed switch in a [52] US. Cl 219/1049, 219/10.75, 219/518, closed position in the absence of a sufficient size 335/219 cooking vessel in position overlying the work coil, the lift. C1.
  • the invention pertains to the art of pan detection arrangements for use in induction heating cooking appa ratus.
  • An arrangement according to the present invention is considered to obviate all of these objections.
  • safety control means responsive to levels of magnetic flux above and below the given range of values for preventing and permitting, respectively, energization of a work coil
  • permanent magnet means is disposed relative to the safety control means and to the location of the base wall of a cooking vessel properly located over the work coil to direct a magnetic field with a flux level above the given values through the safety control means in the absence of a ferromagnetic mass at least comparable to the smallest cooking vessel to be used on said coil and in the proper location, with the magnetic field being shunted sufficiently in the presence of the mass in the proper location to reduce the flux level of the field through the safety control means to a value below the given values so that unless an adequate load for coupling is present above the coil, the coil is prevented from being energized.
  • the safety control means takes the form of a reed switch located generally in a fringe magnetic field between a pair of permanent magnets which have their poles arranged and are spaced apart such that in the absence of a mass corresponding to a properly located cooking vessel the flux level passing through the reed switch causes it to be closed and in the presence of the mass the field is shunted sufficiently that the reed switch opens.
  • FIG. 1 is a schematic representation in the nature of a side elevation showing flux paths in the absence of a magnetic material vessel in position on a work coil;
  • FIG. 2 is a schematic representation, also in the nature of a side elevation, showing the shunting effect of the magnetic material vessel on the flux paths;
  • FIG. 3 is a view in the nature of a vertical cross section showing the relationship between the cooking vessel on the cooking surface, the work coil, and the sensing assembly;
  • FIG. 4 is a plan view of a single cooking unit showing the location of the permanent magnets and the reed switch relative to the cooking location;
  • FIG. 5 is a block diagram and partly schematic view of the .way in which the arrangement according to the invention may be connected to a circuit for controlling the cooking unit.
  • the safety control means is shown in its currently preferred form as a sealed, magnetic reed switch 10 having leaf contacts 12 and 14 which extend out through the ends of the glass envelope to provide terminals.
  • the contacts of the reed switch are normally open but are shown as closed in FIG, 1 becuase of the field from the permanent magnets causes sufficient flux to pass through the leaves of the reed switch to force their contact ends to touch each other.
  • the magnetic lines of force are produced by the pair of permanent magnets 18 and 20 which have their poles arranged as shown to provide the magnetic field schematically illustrated.
  • the orientation of the poles of the left magnet 18 is with north at the top and south at the bottom, while the orientation of the right magnet is reversed.
  • FIG. 2 shows the influence upon the location of the lines of force 16 exerted by placing an extended area mass 22 of magnetic material in proximity to the reed switch 10.
  • the extended area mass of magnetice material which corresponds to the bottom wall of a cooking vessel shunts an adequate portion of the field so that the induced magnetism in the leaves 12 and 14 is insufficient to maintain the switch 10 is a closed position.
  • a refractory material such as a glass ceramic sheet 24 provides a cooking surface above the work coil 26.
  • a suitable I work coil may comprise litz wire which is wound in a spiral and then molded in a rubber compound to hold the wire in place with the proper spacing between successive convolutions.
  • the work coil also typically includes an underlying layer 28 of the rubber compound;
  • the work coil is supported from below by an underlying Transite sheet or block 30 which supports the work coil.
  • the Transite block 30 is supported by means not shown herein.
  • a slot 32 is grooved out of a generally central part of the block 30 to receive the reed switch which is held in place by potting it in with a rubber compound such as Dow Corning Sylgard 185.
  • the groove is made sufficiently long to accommodate the projecting terminal ends of the leads, which are connected to two lead wires 34 and 36 (Fig. 3).
  • the reed switch should be sufficiently long that the requisite sensitivity is provided with respect only to magnetic objects having a sufficiently extended area as to be comparable to the smallest diameter cooking vessel intended for use for the coil.
  • Reed switches which satisfy this requirement are about two to three inches long (including their terminal ends) such as the Hamlin Company DRS-Z and DRT-S.
  • Examples of permanent magnets 18 and which I have found to function satisfactorily are Allegheny General lndox V magnets having top and bottom face areas of about 2 inches by 1 inch, and about inch thick. Such magnets are adequate for operating reed switches with closing requirements of 70 ampere-turns and opening values of 50 or more ampere turns and are not heated appreciably by the coil of the range.
  • the spacing between the facing ends of such magnets used with the identified reed switch is about 4 inches.
  • variations may occur between one reed switch and another, and between one pair of magnets and another current practice is to locate the magnets relative to the reed switch by first bringing them together sufficiently close that the contacts close, and then bringing a magnetic mass comparable to a cooking vessel bottom into the proper location, then moving the magnets apart until the contacts open. The magnets are then fixed in place and the operation checked. It is noted in this respect that a differential may typically be found to exist between the levels of magnetic flux effecting closing and opening of the reed switch. Thus it is responsive to levels of magnetic flux above and below a given pair of values, rather than a specific given value.
  • the reed switch and magnet be centered exactly relative to the center of the work coil. It is only necessary that it be responsive to the bottom wall of the cooking vessel which is placed generally coincident with the work coil, the location of which is generally indicated by the locating indicia 38 provided on the top surface of the cooking surface.
  • the control circuit portion 40 of the arrangement disclosed includes a timing and firing capacitor 42 for the phase controlled rectifier bridge 44.
  • the capacitor charges up from various sources as disclosed in the noted applications, and is discharged by a semiconductor switch through a pulse transformer which couples into and turns on the phase controlled rectifier bridge.
  • pan detector switch could be incorporated in the circuit in other ways, such as by controlling a relay which in turn controls power in one part or another of the circuit.
  • the arrangement according to the invention provides the following safety features. It prevents heating of aluminum foil and possible fire hazards of foil covered packages. It prevents inadvertent heating of metallic cooking utensils such as spoons and forks with consequent burning of the users hand. lt also protects electronic equipment and pacemaker wearers from an energized coil without the shielding provided by a cooking vessel.
  • the switch is located in what may be considered to be a fringe portion of the magnetic field as distinguished from what could be characterized as a main field if the magnets 18 and 20 were of the type in which the poles were at the ends of the bars, and the north pole of 18 were facing a south pole of 20.
  • an induction heating cooking unit of the type including a work coil which is adapted to be coupled electromagnetically to a cooking vessel placed in overlying relation to said coil;
  • safety control means responsive to levels of magnetic flux above and below a given range of values of said flux for preventing and permitting, respectively, energization of said coil;
  • permanent magnet means disposed relative to said safety control means, and to the location of the base wall of a cooking vessel when properly located over said coil, to direct a magnetic field with a flux level above said given values through said safety control means in the absence of a ferromagnetic mass at least comparable to the smallest cooking vessel to be used on said coil and in said proper location;
  • said magnetic field being shunted sufficiently in the presence of said mass in said proper location to reduce the flux level of the field through said safety control means to a value below said given values, so that unless an adequate load for coupling is present above said, coil, said coil is prevented from being energized.
  • said safety controls means comprises switching means closely adjacent said coil;
  • said permanent magnetic means comprise a pair of magnetic mass at least comparable to the base wall of permanent magnets on opposite sides of said the smallest cooking vessel to be used with said coil switching means, said magnets being disposed relawhen in overlying relation to said coil comprising: tive to said switching means, and having their poles safety switch means responsive to the presence of arranged, being spaced apart such that in Said 5 levels of magnetic flux above and below a given allsencef of 531d mass the flux f p f l through range of values to assume one and another condisaid switching means causes sa d switching means on, respectively; tolassume one corldmon and h presence 9 permanent magnet means disposed relative to said salfj l the field shunted sufficlemly from f safety switch means and to the location of the base swltchlng means that the flux levfzl through l wall of the cooking vessel properly located over sw tch ng means is reduced sufficiently that said Said coil, to place said Safety

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Cookers (AREA)
US00365671A 1973-05-31 1973-05-31 Pan detector for induction heating cooking unit Expired - Lifetime US3796850A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US36567173A 1973-05-31 1973-05-31

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US3796850A true US3796850A (en) 1974-03-12

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US (1) US3796850A (enrdf_load_stackoverflow)
JP (1) JPS5021346A (enrdf_load_stackoverflow)
CA (1) CA965484A (enrdf_load_stackoverflow)

Cited By (43)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3852558A (en) * 1974-03-27 1974-12-03 Westinghouse Electric Corp Magnetically coupled control for cooking platform
US3993885A (en) * 1974-02-04 1976-11-23 Matsushita Electric Industrial Co., Ltd. Pan detector for an induction heating apparatus
US3996442A (en) * 1975-01-20 1976-12-07 Westinghouse Electric Corporation Induction heating coil assembly for heating cooking vessels
US4013859A (en) * 1975-06-04 1977-03-22 Environment/One Corporation Induction cooking unit having cooking load sensing device and essentially zero stand-by power loss
US4129767A (en) * 1975-06-17 1978-12-12 Matsushita Electric Industrial Company, Limited Induction heating apparatus having timing means responsive to temporary removal of cooking implement
US4271763A (en) * 1978-05-15 1981-06-09 Berger Philip H Proximity detector
US4308443A (en) * 1979-05-01 1981-12-29 Rangaire Corporation Induction cook-top with improved touch control
US4317016A (en) * 1979-12-27 1982-02-23 Tokyo Shibaura Denki Kabushiki Kaisha Induction heating cooking apparatus
US4319109A (en) * 1979-12-28 1982-03-09 General Electric Company Centered utensil sensor for induction surface units
US4334135A (en) * 1980-12-22 1982-06-08 General Electric Company Utensil location sensor for induction surface units
US4394565A (en) * 1981-11-23 1983-07-19 General Electric Company Power disconnect assembly for electric heating elements
EP0084061A4 (en) * 1981-07-29 1984-04-13 Hamilton Dunn Res Co BEVERAGE WARMER.
US4447691A (en) * 1979-07-31 1984-05-08 Matsushita Electric Industrial Company, Limited Circuit for detecting a utensil load placed asymmetrically relative to an induction heating coil
US4453068A (en) * 1979-05-01 1984-06-05 Rangaire Corporation Induction cook-top system and control
USH43H (en) 1984-12-03 1986-04-01 Xerox Corporation Magnetic latch closure control
EP0328092A1 (de) * 1988-02-11 1989-08-16 Küppersbusch Aktiengesellschaft Kochgerät
US5001328A (en) * 1986-02-26 1991-03-19 E.G.O. Eleckro-Gerate Blanc U. Fischer Cooking unit with radiant heaters
GB2255493A (en) * 1991-05-10 1992-11-11 Haden D H Ltd Heating apparatus with sound actuable switch
US5283412A (en) * 1989-08-04 1994-02-01 Compagnie Europeenne Pour L'equipment Menager - Cepem Temperature-measuring device for an induction-type cooking appliance and appliance having such a device
US5471445A (en) * 1994-06-20 1995-11-28 International Business Machines Corporation Apparatus and method for sensing and holding an item
US5893996A (en) * 1996-02-05 1999-04-13 E.G.O. Elektro-Geratebau Gmbh Electric radiant heater with an active sensor for cooking vessel detection
US6300603B1 (en) 2000-06-08 2001-10-09 Stephen Patrick Edwards Stovetop burner with safety feature
US6403932B1 (en) 2001-01-09 2002-06-11 Emerson Electric Co. Controller for a heating unit in a cooktop and methods of operating same
US6417496B1 (en) 2000-12-22 2002-07-09 Emerson Electric Co. Modular heating unit for cooktops
US6492627B1 (en) 2001-07-26 2002-12-10 Emerson Electric Co. Heating unit and control system for cooktops having capability to detect presence of a pan and methods of operating same
US20040255409A1 (en) * 2001-12-04 2004-12-23 Alexander Hilscher Dental cleaning device
US20050000044A1 (en) * 2001-03-14 2005-01-06 Braun Gmbh Method and device for cleaning teeth
US20050011025A1 (en) * 2000-03-17 2005-01-20 Braun Gmbh Dental cleaning device
US20050269314A1 (en) * 2004-06-08 2005-12-08 Rael Paul J Magnetic safety feature for cookware and cooking stoves
US20070108184A1 (en) * 2004-05-10 2007-05-17 Kabushiki Kaisha Toshiba Heating cooker
WO2008110450A3 (de) * 2007-03-13 2009-01-22 Bsh Bosch Siemens Hausgeraete Kochfeld und verfahren zum detektieren eines kochgeschirrteils
US20100299856A1 (en) * 2007-05-15 2010-12-02 Rudolf Majthan Toothbrush attachment and method for the production thereof
US20110122987A1 (en) * 2004-12-23 2011-05-26 Braun Gmbh Replaceable Accessory for a Small Electrical Appliance and Method of Monitoring the Usage of the Accessory
US8443476B2 (en) 2001-12-04 2013-05-21 Braun Gmbh Dental cleaning device
US8558430B2 (en) 2010-08-19 2013-10-15 Braun Gmbh Resonant motor unit and electric device with resonant motor unit
US8631532B2 (en) 2011-07-25 2014-01-21 Braun Gmbh Oral hygiene device
US9099939B2 (en) 2011-07-25 2015-08-04 Braun Gmbh Linear electro-polymer motors and devices having the same
US9155130B2 (en) 2012-05-29 2015-10-06 General Electric Company Method to detect a position of a cookware utensil in an induction cooktop system
US9220365B1 (en) 2014-04-23 2015-12-29 Chinwe Okonkwo Electromagnet for fastening cookware to a stovetop element
US9226808B2 (en) 2011-07-25 2016-01-05 Braun Gmbh Attachment section for an oral hygiene device
US9425638B2 (en) 1999-11-01 2016-08-23 Anthony Sabo Alignment independent and self-aligning inductive power transfer system
US20180153327A1 (en) * 2015-07-28 2018-06-07 Mark Goodson Beverage Cooler and Heater
EP4033153A1 (en) * 2021-01-20 2022-07-27 Electrolux Appliances Aktiebolag Domestic appliance with stand-by function

Families Citing this family (1)

* Cited by examiner, † Cited by third party
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JPS5739574A (en) * 1980-08-22 1982-03-04 Toshiba Corp Semiconductor device

Cited By (77)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3993885A (en) * 1974-02-04 1976-11-23 Matsushita Electric Industrial Co., Ltd. Pan detector for an induction heating apparatus
US3852558A (en) * 1974-03-27 1974-12-03 Westinghouse Electric Corp Magnetically coupled control for cooking platform
US3996442A (en) * 1975-01-20 1976-12-07 Westinghouse Electric Corporation Induction heating coil assembly for heating cooking vessels
US4013859A (en) * 1975-06-04 1977-03-22 Environment/One Corporation Induction cooking unit having cooking load sensing device and essentially zero stand-by power loss
US4129767A (en) * 1975-06-17 1978-12-12 Matsushita Electric Industrial Company, Limited Induction heating apparatus having timing means responsive to temporary removal of cooking implement
US4271763A (en) * 1978-05-15 1981-06-09 Berger Philip H Proximity detector
US4453068A (en) * 1979-05-01 1984-06-05 Rangaire Corporation Induction cook-top system and control
US4308443A (en) * 1979-05-01 1981-12-29 Rangaire Corporation Induction cook-top with improved touch control
US4447691A (en) * 1979-07-31 1984-05-08 Matsushita Electric Industrial Company, Limited Circuit for detecting a utensil load placed asymmetrically relative to an induction heating coil
US4317016A (en) * 1979-12-27 1982-02-23 Tokyo Shibaura Denki Kabushiki Kaisha Induction heating cooking apparatus
US4319109A (en) * 1979-12-28 1982-03-09 General Electric Company Centered utensil sensor for induction surface units
US4334135A (en) * 1980-12-22 1982-06-08 General Electric Company Utensil location sensor for induction surface units
EP0084061A4 (en) * 1981-07-29 1984-04-13 Hamilton Dunn Res Co BEVERAGE WARMER.
US4394565A (en) * 1981-11-23 1983-07-19 General Electric Company Power disconnect assembly for electric heating elements
USH43H (en) 1984-12-03 1986-04-01 Xerox Corporation Magnetic latch closure control
US5001328A (en) * 1986-02-26 1991-03-19 E.G.O. Eleckro-Gerate Blanc U. Fischer Cooking unit with radiant heaters
EP0328092A1 (de) * 1988-02-11 1989-08-16 Küppersbusch Aktiengesellschaft Kochgerät
US5283412A (en) * 1989-08-04 1994-02-01 Compagnie Europeenne Pour L'equipment Menager - Cepem Temperature-measuring device for an induction-type cooking appliance and appliance having such a device
GB2255493A (en) * 1991-05-10 1992-11-11 Haden D H Ltd Heating apparatus with sound actuable switch
GB2255493B (en) * 1991-05-10 1995-04-05 Haden D H Ltd Heating apparatus
US5471445A (en) * 1994-06-20 1995-11-28 International Business Machines Corporation Apparatus and method for sensing and holding an item
US5893996A (en) * 1996-02-05 1999-04-13 E.G.O. Elektro-Geratebau Gmbh Electric radiant heater with an active sensor for cooking vessel detection
US9425638B2 (en) 1999-11-01 2016-08-23 Anthony Sabo Alignment independent and self-aligning inductive power transfer system
US7624467B2 (en) 2000-03-17 2009-12-01 Braun Gmbh Dental cleaning device
US7979939B2 (en) 2000-03-17 2011-07-19 Braun Gmbh Dental cleaning device
US20050011025A1 (en) * 2000-03-17 2005-01-20 Braun Gmbh Dental cleaning device
US6300603B1 (en) 2000-06-08 2001-10-09 Stephen Patrick Edwards Stovetop burner with safety feature
US6417496B1 (en) 2000-12-22 2002-07-09 Emerson Electric Co. Modular heating unit for cooktops
US6403932B1 (en) 2001-01-09 2002-06-11 Emerson Electric Co. Controller for a heating unit in a cooktop and methods of operating same
US20070234493A1 (en) * 2001-03-14 2007-10-11 Braun Gmbh, A Germany Corporation Dental Cleaning Device
US7621015B2 (en) 2001-03-14 2009-11-24 Braun Gmbh Method and device for cleaning teeth
US8671493B2 (en) 2001-03-14 2014-03-18 Braun Gmbh Dental cleaning device
US7673360B2 (en) 2001-03-14 2010-03-09 Braun Gmbh Dental cleaning device
US20050000044A1 (en) * 2001-03-14 2005-01-06 Braun Gmbh Method and device for cleaning teeth
US20080010771A1 (en) * 2001-03-14 2008-01-17 The Gillette Company Method and device for cleaning teeth
US20080020352A1 (en) * 2001-03-14 2008-01-24 Alexander Hilscher Method and device for cleaning teeth
US20080022469A1 (en) * 2001-03-14 2008-01-31 Alexander Hilscher Dental cleaning device
US7774886B2 (en) 2001-03-14 2010-08-17 Braun Gmbh Method and device for cleaning teeth
US7661172B2 (en) 2001-03-14 2010-02-16 Braun Gmbh Dental cleaning device
US20080022471A1 (en) * 2001-03-14 2008-01-31 Alexander Hilscher Dental cleaning device
US7770251B2 (en) 2001-03-14 2010-08-10 Braun Gmbh Method and device for cleaning teeth
US7861349B2 (en) 2001-03-14 2011-01-04 Braun Gmbh Method and device for cleaning teeth
US6492627B1 (en) 2001-07-26 2002-12-10 Emerson Electric Co. Heating unit and control system for cooktops having capability to detect presence of a pan and methods of operating same
US8443476B2 (en) 2001-12-04 2013-05-21 Braun Gmbh Dental cleaning device
US20040255409A1 (en) * 2001-12-04 2004-12-23 Alexander Hilscher Dental cleaning device
US20100281637A1 (en) * 2001-12-04 2010-11-11 Braun Gmbh Dental Cleaning Device
US8683637B2 (en) 2001-12-04 2014-04-01 Braun Gmbh Dental cleaning device
US8181301B2 (en) 2001-12-04 2012-05-22 Braun Gmbh Dental cleaning device
US8071919B2 (en) * 2004-05-10 2011-12-06 Kabushiki Kaisha Toshiba Heating cooker
US20070108184A1 (en) * 2004-05-10 2007-05-17 Kabushiki Kaisha Toshiba Heating cooker
US20060283437A1 (en) * 2004-06-08 2006-12-21 Rael Paul J Magnetic safety feature for cookware and cooking stoves
US7135658B2 (en) * 2004-06-08 2006-11-14 Paul J Rael Magnetic safety feature for cookware and cooking stoves
US8735779B2 (en) 2004-06-08 2014-05-27 Paul J. Rael Magnetic safety feature for cookware and cooking stoves
US20100175681A1 (en) * 2004-06-08 2010-07-15 Rael Paul J Magnetic safety feature for cookware and cooking stoves
US20050269314A1 (en) * 2004-06-08 2005-12-08 Rael Paul J Magnetic safety feature for cookware and cooking stoves
US7667161B2 (en) * 2004-06-08 2010-02-23 Rael Paul J Magnetic safety feature for cookware and cooking stoves
US20080142527A1 (en) * 2004-06-08 2008-06-19 Rael Paul J Magnetic safety feature for cookware and cooking stoves
US8164029B2 (en) * 2004-06-08 2012-04-24 Rael Paul J Magnetic safety feature for cookware and cooking stoves
US7355151B2 (en) 2004-06-08 2008-04-08 Paul J Rael Magnetic safety feature for cookware and cooking stoves
US20110122987A1 (en) * 2004-12-23 2011-05-26 Braun Gmbh Replaceable Accessory for a Small Electrical Appliance and Method of Monitoring the Usage of the Accessory
US8218711B2 (en) 2004-12-23 2012-07-10 Braun Gmbh Replaceable accessory for a small electrical appliance and method of monitoring the usage of the accessory
ES2321262B1 (es) * 2007-03-13 2010-03-04 Bsh Electrodomesticos España S.A. Campo de coccion y procedimiento para la deteccion de una pieza de bateria de cocina.
WO2008110450A3 (de) * 2007-03-13 2009-01-22 Bsh Bosch Siemens Hausgeraete Kochfeld und verfahren zum detektieren eines kochgeschirrteils
ES2321262A1 (es) * 2007-03-13 2009-06-03 Bsh Electrodomesticos España S.A. Campo de coccion y procedimiento para la deteccion de una pieza de bateria de cocina.
US20100299856A1 (en) * 2007-05-15 2010-12-02 Rudolf Majthan Toothbrush attachment and method for the production thereof
US8558430B2 (en) 2010-08-19 2013-10-15 Braun Gmbh Resonant motor unit and electric device with resonant motor unit
US9226808B2 (en) 2011-07-25 2016-01-05 Braun Gmbh Attachment section for an oral hygiene device
US8631532B2 (en) 2011-07-25 2014-01-21 Braun Gmbh Oral hygiene device
US9387059B2 (en) 2011-07-25 2016-07-12 Braun Gmbh Oral cleaning tool for an oral hygiene device
US9099939B2 (en) 2011-07-25 2015-08-04 Braun Gmbh Linear electro-polymer motors and devices having the same
US10327876B2 (en) 2011-07-25 2019-06-25 Braun Gmbh Oral cleaning tool for an oral hygiene device
US9155130B2 (en) 2012-05-29 2015-10-06 General Electric Company Method to detect a position of a cookware utensil in an induction cooktop system
US9220365B1 (en) 2014-04-23 2015-12-29 Chinwe Okonkwo Electromagnet for fastening cookware to a stovetop element
US20180153327A1 (en) * 2015-07-28 2018-06-07 Mark Goodson Beverage Cooler and Heater
US10905268B2 (en) * 2015-07-28 2021-02-02 Mark Goodson Beverage cooler and heater
EP4033153A1 (en) * 2021-01-20 2022-07-27 Electrolux Appliances Aktiebolag Domestic appliance with stand-by function
WO2022157070A1 (en) * 2021-01-20 2022-07-28 Electrolux Appliances Aktiebolag Domestic appliance with stand-by function

Also Published As

Publication number Publication date
AU6879174A (en) 1975-11-13
JPS5021346A (enrdf_load_stackoverflow) 1975-03-06
CA965484A (en) 1975-04-01

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