Abstract: A heater is provided that has a temperature sensing control system which can be used for both temperature control and over-temperature protection against element burnout. The temperature control system is comprised of an inlet temperature sensing assembly positioned at the inlet to the heater element and an exit thermocouple positioned in the exit end of the heater element. The exit thermocouple may be used for control the heater temperature and provide over-temperature protection. The inlet temperature sensing assembly is used to detect low or no air flow conditions which could lead to heater element failure.

Abstract: An electrical domestic appliance containing a main switch for turning the current power supply to the electrical domestic appliance on and off. The main switch having a predetermined turn-on time period during which the main switch must be actuated in order to move from the off-position to the on-position. The main switch predetermined turn-on period can be selected and adjusted by the customer through predetermined time limits.

Abstract: A heat treating apparatus is provided to apply a heat treatment on a substrate. Prior to the heat treatment, an exclusive transfer mechanism transfers the substrate from a cooling plate onto a heating plate for heating the substrate. Before mounting the substrate on the heating plate, the control mode for heater modules for heating the heating plate on power supply module is switched from a PID control by a regulating part in a controller of the apparatus to a MV control by a fixed-pattern output part in the controller. Next, at a predetermined timing since the substrate has been mounted on the heating plate, the MV control is switched to the PID control. Consequently, it becomes possible to quickly restore a reduce temperature of the heating plate prior to the mounting of substrate on the heating plate and also possible to quickly stabilize a so-raised temperature of the heating plate, accomplishing a heating process with high accuracy and shirt time.

Abstract: The present invention relates to a heating device having at least a first heating element 102 for heating at least one protective sleeve 105, 602 arranged around at least a first uncoated optical fiber section 501, 603. Said sleeve 105, 602 being arranged to shrink when exposed to heat to form a protecting member tightly enclosing said uncoated optical fiber section 501, 603. The at least first heating element is flexible, and arranged to take at least a first open state and a second substantially closed state. Said first open state is suitable for inserting and removing said protecting sleeve and fiber into and out off said heating device. Said heating element, in said second state, substantially surrounds said sleeve to form an enclosure around said sleeve, so that said heating element radiates heat around substantially the complete circumference of said sleeve.

Abstract: A cooking appliance includes an oven cavity, an electric heating element and a rapid cook heating system both of which being operable on either one of first and second supply voltages, and a controller including a memory module having stored therein first and second control algorithms. The controller will operate the cooking appliance based on one of the first or second control algorithm depending upon whether the cooking appliance is connected to the first or second supply voltages respectively. Preferably, the appliance includes a sensor for signaling the controller as to the presence of either the first or second supply voltage. In the alternative, the appliance can be manually set for use with a particular voltage supply.

Abstract: Immediately after a cold substrate G is placed on a substrate table 3, a large electric power P1 is supplied to a heating element 32 embedded in the substrate table for a time period T1 so that temperature of the substrate table overshoots a target temperature, and thereafter zero or very small electric power P2 is supplied to the heating element for a time period T2 so that the temperature of the substrate table 3 is lowered to the target temperature while temperature of the substrate continues to rise up to the target temperature. When both the temperature of the substrate table and of the substrate reaches approximately to the target temperature after the time period T2 has elapsed, control of the electric power is entrusted to a PID controller.

Abstract: A method modifies friction between an object and ice or snow. The method utilizes a heating element to apply a pulse of thermal energy to an interface between the object and the ice or snow; the first pulse is sufficient to melt an interfacial layer of ice at the interface. Water forming the interfacial layer refreezes to form a bond between the object and the ice or snow. The steps of the method may be repeated to form a second bond between the object and the ice or snow.

Abstract: An improved dry heat method and apparatus for thawing frozen biological fluids utilizing electrically heated plates and oscillatory motion to enhance heat transfer by mixing as the fluid thaws. Bags of frozen fluid to be thawed are lightly squeezed between two heating plates, one of which is gently oscillated to facilitate mixing of the thawing fluid, increasing heat transfer and reducing time required for thawing. Direct contact of the heating plates against the bag surfaces increases heat transfer by eliminating insulative effects of another bag wall and a water boundary layer, compared to water bath units. Flat (or curved to conform to bag) heat pipes are preferred as heating plates compared to plain aluminum sheet. Flat heat pipes have the property of an isothermal heating surface, thus maximizing heat transfer to the coldest areas, preventing hot spots, and simplifying heating plate temperature control.

Abstract: A control device for an electric blanket includes a voltage drop rectifier circuit connected to an AC power source, a control gate circuit, a zero-across detecting circuit connected to the AC power source, a central processing circuit connected to the zero-across detecting circuit, an activating circuit, and a button circuit. The control gate circuit includes a triac electrically connected in series to the AC power source. The activating circuit includes an input connected to the central processing unit and an output connected to the gate of the triac of the control gate circuit. The central processing circuit includes a central processor and outputs signals to control the activating circuit, the control gate circuit, and the heating element such that the heating element is activated when the zero-across detecting circuit detects that a voltage of the AC power source approximates zero and thus sends a signal to the central processing circuit.

Abstract: An improved variable resistor at least partially compensates for non-linearities in an electrical circuit containing a heating element, for example, a thin-film heating element. A controllable heater includes a heating element, a voltage source (for example, a standard AC electrical outlet) coupled to the heating element, and a variable resistor coupled to the heating element and voltage source. The variable resistor includes a fixed resistive element (for example, one or more thin-film resistors) and a moveable element such as a slider control. The moveable element adjustably contacts the fixed resistive element at a contact point associated with the position such that the variable resistor has a resistance that is at least partially non-linearly related to the position, but wherein the heating element has a dissipated power that is at least partially linearly related to the position of the variable resistor.

Abstract: A heater inspection apparatus including an applying unit, a current detector, a voltage detector, a temperature detector, a memory, a first calculating unit, a second calculating unit and a finding unit is provided. The applying unit applies an electrical power to a heater based on an AC power source. The current detector detects a current flowing through the heater. The voltage detector detects a voltage applied to the heater. The temperature detector detects a temperature of the heater. A temperature coefficient of resistance is stored in advance on the memory. The first calculating unit and the second calculating unit respectively calculate a resistance of the heater at an inspection time and a reference time. The finding unit finds a deterioration degree of the heater based on results of the first and second calculating units.

Abstract: A heating apparatus includes a heating roller that is heated by heating units, a main power supply that supplies power from an external power supply to the main heating unitl, and an auxiliary power supply that supplies power to the auxiliary heating unit. The auxiliary power supply further includes a mass capacitor of multiple capacitor cells, which are charged by the external power supply. The connection mode of the capacitor cells is changed at least at the time of electric discharge.

Abstract: A combination selector switch and infinite switch energy regulator provides a plurality of simmer voltages. An infinite switch energy regulator for adapting input voltage level to an average output voltage level is provided. This energy regulator has a rotatable shaft for adjusting the average output voltage level. An input voltage selector, such as an F switch, selects between a plurality of input voltages by actuation of a rotatable cam. The output of the input voltage selector is provided as an input to the infinite switch. The rotatable shaft is also operatively coupled to the rotatable cam and thus controls the input voltage selector as well as the infinite switch. The selective provision of two different voltage levels as an input to the infinite switch permits a plurality of simmer voltages when the unit is assembled in an electric range.

Abstract: A cooking appliance includes a cooktop having at least one heating element, a controller and a control element linked to the controller and associated with operation of the heating element. Specifically, the control element includes first and second operational setting schemes which provide a consumer with a higher degree of control over operation of the heating element. More specifically, selection of the first scheme operates the heating element at a selected level, while selection of the second scheme causes the heating element to operate at an initial high level and then to automatically convert to a lower level.

Abstract: A device and method for controlling a heater of a drying machine is disclosed, which includes a plurality of switches, each switch having a plurality of input terminals being supplied with different input voltages and an output terminal, and each switch connecting any one of the input terminals with the output terminal according to a switching control signal, and a heater connected to the output terminal of each switch and varying its temperature according to the voltage being supplied therein.

Abstract: Systems and methods for thermally modifying an ice-to-object interface. One system includes a power supply configured to generate a magnitude of power. The magnitude of the power is sufficient to melt an interfacial layer of ice at the interface; typically the interfacial layer has a thickness in a range one micron to one millimeter. A controller may be used to limit the duration in which power supply generates the magnitude of the power, to limit unneeded heat energy dissipation into the environment. Modulating the pulsed heating energy to the interface modifies a coefficient of friction between the object and the ice.

Abstract: The operating temperature of a gas sensor capable of sensing a gas or a gas composition at a high temperature, for example 1000° C. is maintained constant over the entire volume of a gas sensor layer or function layer (4) secured to a sensor carrier section of the gas sensor by supplying heat to the gas sensor layer (4) in such a way that varying heat dissipations in the sensor carrier section are compensated. For this purpose, an electrical heater for heating the gas sensor layer (4) has individual heater sections with different heating resistance values which depend on a spacing between any individual heater section and the tip of the sensor carrier section.

Abstract: An image formation apparatus includes a fixing heater, and a zero-cross detector that detects zero-cross points of a frequency of an alternating current (AC) power supply connected to the heater. The image formation apparatus also includes a controller that controls light-on of the heater by pulse-width-modulation (PWM)-controlling the frequency of the AC power supply, that controls a duty width of a PWM control signal for the frequency of the AC power supply for a half period that corresponds to a period between the adjacent zero-cross points detected by the zero-cross detector, and that controls an amplitude of an input current from the AC power supply so that a waveform of the input current becomes a rough approximation of a sine wave.

Abstract: A cooking appliance includes an oven cavity, an electric heating element and a rapid cook heating system both of which being operable on either one of first and second supply voltages, and a controller including a memory module having stored therein first and second control algorithms. The controller will operate the cooking appliance based on one of the first or second control algorithm depending upon whether the cooking appliance is connected to the first or second supply voltages respectively. Preferably, the appliance includes a sensor for signaling the controller as to the presence of either the first or second supply voltage. In the alternative, the appliance can be manually set for use with a particular voltage supply.

Abstract: The present invention suitably provides a method and apparatus for controlling the temperature of a liquid vaporizer heating element, and thereby the rate of evaporation and level of fragrance delivery from the same. In accordance with one exemplary embodiment of the present invention, the device may include a switch that suitably allows the temperature of various types of heating elements to be controlled for different levels of fragrance output. For example, an exemplary embodiment may include a two-pronged plug adaptable to typical outlets that might be found in residential homes or businesses. In accordance With another exemplary embodiment of the present invention, the electrical switch generally provides varying resistance values to the electric circuitry of the vaporizer such that, by changing the switch setting, the operating temperature of the wick is controlled and thus the rate of fragrance evaporation from the vaporizer.

Abstract: A clothes dryer is provided with control elements which enable a user to set both a drying temperature and the amount of power sent to a main heating element of the dryer during a dryer cycle. In accordance with the most preferred form of the invention, an infinitely variable power supply controller is used to selectively establish the maximum power provided to the main heating element during the dryer cycle. The controller preferably is adjusted by a slider switch mounted on a control panel of the dryer. The switch is preferably provided with indicators to indicate the established power level.

Abstract: The present invention discloses to an improved oven controller structure, which adds an external insulating cover to a controller disposed at the periphery of an oven according to the position of placing the oven, and the controller could be changed to one with cable transmission, wireless sensing, or embedded controller according to the predetermined configuration. The controller is detachable from the oven, and the oven can be controlled rapidly by a controller at the outside of the housing and the information about the operation of each component of inside the oven is known.

Abstract: The invention relates to an electric heating system for a motor vehicle in which a PTC heating element (4) is controlled by a regulator (1) by means of an infinitely variable electronic power system (2). The regulator (1) receives a status signal (u) that indicates the power available from the dynamo (6). The control signal (x) for the electronic power system (2) is preferably calculated from the latter by means of a PI algorithm in such a way that the dynamo/altenator (6) is utilized to a maximum degree without putting at risk a sufficient supply to other electrical loads (5). The regulator (1) can also be connected to a user interface (3) for displaying and/or inputting information.

Abstract: A measuring circuit capable of performing a high-accuracy measurement by eliminating inductive influence from an ambient noise voltage source. An electric circuit including a signal circuit of high impedance, a wiring conductor and a meter is provided with a shielding resistance member having a significantly lower resistance than that of the signal circuit in dependence on an inter-terminal voltage of the high impedance signal circuit and a shield formed of an electrically conductive material disposed in association with the wiring conductor. A voltage distribution function of the shielding resistance member is matched equally to that of an inter-terminal voltage distribution function of the signal circuit. By measuring a line voltage through the medium of the high impedance signal circuit shielded by the shielding resistor, high accuracy measurement can be realized without undergoing adverse influences of parasitic capacitance and induction.

Abstract: A hot water tank monitoring system is designed to shut off the water supply to the hot water tank and to shut off either the electrical supply or the gas supply to the heating unit of the hot water tank in response to sensing of malfunction of one or more of a number of different sensed parameters. These parameters include a water leak detector located beneath the water tank, a water level float sensor, a temperature sensor to sense excess temperature, and a pressure sensor located in the line between the pressure relief valve and the blow-out outlet of the water tank. Signals from the various sensors are supplied to a controller, which provides signals to a LED status indicator, and also operates to provide alarm signals through a modem over telephone lines to remote locations and to operate an alarm.

Abstract: A control circuit of a programmable coffee maker includes an input unit for inputting a preset brewing time, a heater controller for controlling electrical connection between an electric heating device and a power supply, a sensor unit for providing a cancel signal when temperature at a supply pipe connected to a water reservoir and heated by the heating device reaches a predetermined critical temperature, and a processor having an internal clock with a current time output. The processor controls the heater controller to make electrical connection between the heating device and the power supply when the preset brewing time coincides with the current time output, and cancels the preset brewing time and controls the heater controller to break the electrical connection between the heating device and the power supply after the processor receives the cancel signal from the sensor unit.

Abstract: The invention describes an electric heating system for motor vehicles with the following characteristics:

Abstract: A microwave oven includes a direct current (DC) power supply unit which supplies DC power to a magnetron so as to suppress noise induced in a high voltage line. The DC power supply unit includes at least one rectifying diode and a choke coil. The rectifying diode rectifies high frequency alternating current (AC) power generated by a heater coil into the DC power to suppress noise induced in the high voltage line of a high voltage transformer. The choke coil forms ripples in the DC power and effectively prevents a moding of the magnetron, which is generated where a constant DC voltage is supplied.

Abstract: A state control apparatus includes a calculator for calculating adjustment amounts for adjusting a plurality of end effecting devices on the basis of preset values and measured amounts measured by a plurality of meters. The measured amounts indicate respective states of the end effecting devices. The adjustment amounts are required for conforming the measured amounts to the preset values, respectively. The state control apparatus further includes a parameter generator for generating a plurality of parameters on the basis of settings by a user. The state control apparatus further includes a comprehensive controller for outputting activating signals for activating the respective end effecting devices based on the respective adjustment amounts and the plurality of parameters.

Abstract: An electrical heater control system reduces flicker. The system includes an electrical heating system; an AC (alternating current) power source for supplying AC current to the electrical heating system; an AC power control device connected between the electrical heating system and the AC power source for controlling the supply of AC current to the electrical heating system; and a controller unit coupled to the AC power control device for activating the device at zero crossings of the AC power to minimize flicker in AC current supplied to the electrical heating system from the AC power source.

Abstract: A heating and cooling apparatus is provided which employs a series of thermally conductive plates thermally coupled to heating and cooling devices to heat or cool a mounting plate loaded with semiconductor devices. The mounting plate is assembled on a heating plate, which is then assembled on a cooling plate. The heating plate includes upper and lower plates with a heater therebetween which can heat the heating plate to a desired temperature, which in turn heats the mounting plate and the semiconductor devices. The cooling plate has ‘S’ shaped flow grooves formed throughout. When cooling fluid is flowed through the flow grooves, the cooling plate is cooled, which cools the heating plate, which in turn cools the mounting plate and the semiconductor devices.

Abstract: A power supply system for electrically heated pipelines is provided. A variable frequency drive supplies power to the pipeline from an external source of electrical power. An isolation transformer and a contactor or isolating switch may be used between the variable frequency drive and the pipeline. A controller may be used in the system to control special sequences of power level and other needs for heating a pipeline.

Abstract: There is disclosed an electric appliance (100, 200, 300, 400, 500, 600, 700, 800) with a positive temperature coefficient (PTC) heater (102, 202, 302, 506, 702) and a number of batteries (106, 206, 308, 406, 508, 606, 708, 806), in which the PTC heater (102, 202, 302, 506, 702) is adapted to be powered by the batteries (106, 206, 308, 406, 508, 606, 708, 806) and an outside electric power source, and the PTC heater (102, 202, 302, 506, 702) is adapted to be powered by the outside electric power source when the electric appliance (100, 200, 300, 400, 500, 600, 700, 800) is started, and to be subsequently powered by the batteries (106, 206, 308, 406, 508, 606, 708, 806).

Abstract: The present invention suitably provides a method and apparatus for controlling the temperature of a liquid vaporizer heating element, and thereby the rate of evaporation and level of fragrance delivery from the same. In accordance with one exemplary embodiment of the present invention, the device may include a switch that suitably allows the temperature of various types of heating elements to be controlled for different levels of fragrance output. For example, an exemplary embodiment may include a two-pronged plug adaptable to typical outlets that might be found in residential homes or businesses. In accordance with another exemplary embodiment of the present invention, the electrical switch generally provides varying resistance values to the electric circuitry of the vaporizer such that, by changing the switch setting, the operating temperature of the wick is controlled and thus the rate of fragrance evaporation from the vaporizer.

Abstract: A system and method for developing a heat treatment process using a model radiative-heating oven, which repeatably and accurately simulates an industrial heat treatment system. In order to simulate the industrial heat treatment system, the model radiative-heating oven uses a variety of scaling factors, such as heating density parameters. The model radiative-heating oven also may have a quickly openable and closable object carrier, which facilitates a timely start and end of a desired heat treatment process. An oven temperature stabilizer also may be provided for thermally stabilizing the model radiative-heating oven prior to the desired heat treatment process. The present technique also may utilize a variety of heat profile controls, such as time, temperature, and power levels, to provide the desired heat profile in the heat treatment process.

Abstract: A measuring circuit capable of performing a high-accuracy measurement by eliminating inductive influence from an ambient noise voltage source. An electric circuit including a signal circuit of high impedance, a wiring conductor and a meter is provided with a shielding resistance member having a significantly lower resistance than that of the signal circuit in dependence on an inter-terminal voltage of the high impedance signal circuit and a shield formed of an electrically conductive material disposed in association with the wiring conductor. A voltage distribution function of the shielding resistance member is matched equally to that of an inter-terminal voltage distribution function of the signal circuit. By measuring a line voltage through the medium of the high impedance signal circuit shielded by the shielding resistor, high accuracy measurement can be realized without undergoing adverse influences of parasitic capacitance and induction.

Abstract: An Electric Appliance including a PTC Heating Member and a Method of Operating Same There is disclosed an electric appliance (100, 200, 300, 400, 500, 600, 700, 800) with a positive temperature coefficient (PTC) heater (102, 202, 302, 506, 702) and a number of batteries (106, 206, 308, 406, 508, 606, 708, 806), in which the PTC heater (102, 202, 302, 506, 702) is adapted to be powered by the batteries (106, 206, 308, 406, 508, 606, 708, 806) and an outside electric power source, and the PTC heater (102, 202, 302, 506, 702) is adapted to be powered by the outside electric power source when the electric appliance (100, 200, 300, 400, 500, 600, 700, 800) is started, and to be subsequently powered by the batteries (106, 206, 308, 406, 508, 606, 708, 806).

Abstract: A speed cooking oven includes a combination of radiant cooking units and a microwave cooking unit manually controllable using a rotary dial input selector coupled to a control panel for user selection of desired oven features. An alphanumeric display displays prompts and information to guide users through a feature selection process. A microprocessor executes a cooking algorithm based upon user defined constants entered via the rotary dial according to prompts on the alphanumeric display.

Abstract: A voltage from an AC power source is converted into a DC voltage in an input-side rectifier-smoother circuit. The DC voltage is then converted into a high-frequency voltage in an inverter, and the resulting high-frequency voltage is voltage-transformed in a transformer. The voltage-transformed high-frequency voltage is converted into a DC voltage in an output-side rectifier-smoother circuit, which is applied via output terminals to a load. The input-side and output-side rectifier-smoother circuits, the inverter and the transformer are enclosed in a casing having a plastic panel. The output terminal of the apparatus is mounted on the plastic panel.

Abstract: A kitchen appliance having a heating element and a control for controlling supply of electricity to the heating element. The control comprises a temperature sensor comprising a thermistor or thermocouple; an electronic controller electrically connected to the temperature sensor; and a user actuatable input connected to the electronic controller for selecting upper and lower temperatures for cycling OFF and ON supply of electricity to the heating element. For all of the user selectable upper temperatures, the electronic controller is adapted to turn OFF supply of electricity to the heating element when an output from the temperature sensor indicates a sensed temperature which is equal to or above the selected upper temperature plus a first predetermined temperature value.

Abstract: The oven includes a housing and a support member located in the housing for supporting food to be cooked. A lower electrical heating element is located below the support member. Two laterally spaced apart upper electrical heating elements are supported above the support member and the food to be cooked. An electrical system is provided for supplying electrical power to the lower electrical heating element and to the two upper electrical heating elements. A control unit is provided for controlling electrical power applied to the lower heating element and to the two upper electrical heating elements to allow electrical power to be applied to each of the two upper electrical heating elements simultaneous or separately. The control unit includes a controller in which is stored a plurality of menus with each menu being assigned given cooking time and power level parameters for controlling electrical power to the upper heating elements for operating these heating elements either separately or together.

Abstract: A halogen heater control apparatus of a microwave oven and a method thereof, comprises a plurality of halogen heaters which are connected to a utility AC power source, and a halogen heater switching unit. The halogen heater and incrementally alters infrared wavelengths from the halogen heater, and a microcomputer controls the operation of the halogen heater switching unit. The present invention is capable of optimum foodstuff heating and cooking by incrementally altering and controlling the infrared wavelengths from the halogen heater by controlling the utility AC power source duty cycle to the halogen heater in accordance with control signals generated by the microcomputer.

Abstract: A control is provided for an electrical appliance having at least one electrical operating device associated with a working area, particularly for an electrical cooking appliance with a heating element and a glass ceramic area as the working area. The control has a power unit for supplying the operating device with electric power, as well as a control unit adapted to the power unit for controlling the latter. The control unit is housed in an operating unit, separate from the electrical appliance and which comprises operating elements and display devices for displaying the operating states of the electrical appliance or the control. For the control-effective connection between the control and power units, there is a coupling device positioned laterally alongside the glass ceramic cooking area and which permits a fitting of the operating unit outside the glass ceramic cooking area in a docking position, where the control unit and power unit are power-effectively connected.

Abstract: A heating apparatus for performing heat treatment on a wafer applied with a resist before or after exposure includes a heating plate for heating a wafer which is placed on the heating plate, a light intensity detecting apparatus for irradiating light on the wafer to detect intensity of reflected light from the resist on the wafer, and a control section for controlling heating performed by the heating plate on the basis of the detected intensity of reflected light so that heating amount applied to a plurality of wafers becomes constant. Accordingly, the heating amount of the wafer can be controlled to be constant and variations in dimension of resist patterns can be reduced.

Abstract: The present invention provides both a process and apparatus for rapidly warming and delivering relatively high volumes of a physiological fluid. Unique to this invention is the ability to warm and infuse physiological fluids at a rate of up to about 1000 ml/min without causing damage to the fluid components, e.g. lysing or rupture of cells, or upsetting the normothermic equilibrium of the patient. Further unique to this invention is the utilization of a 12 VDC source, e.g. a battery source, as an amperage supplement to be used simultaneously with an AC power source, thereby enabling the heating of physiological fluids at a rate which surpasses that normally attainable through the sole use of facility provided AC power.

Abstract: A drainmast including an electronic temperature detecting and control circuit contained in a fairing detects the temperature of a drain tube and the electronic temperature detecting and control circuit selectively applies voltage to one or more heating elements in accordance with the detected temperature. The applied voltage may be unequally applied to the heating elements. The electronic temperature detecting and control circuit only requires two leads, one for ground and one for the supplied voltage. The drainmast is reliable, has a long life span and rapidly responds to temperature changes.

Abstract: The invention is a dual power source high heat electrical grill whose primary application is as an outdoor or indoor grill which uses the combination of AC and DC powered elements in a hybrid configuration to produce as much heat as conventional outdoor gas grills and more than could otherwise be produced by a conventional electric grill.

Abstract: A sensor based automated cooking apparatus is provided. A humidity sensor measures the moisture content within a cooking cavity. An output of the sensor is provided to a digital filter to remove noise therefrom before being passed to a feature extractor which performs a data compression step and extracts salient features relating to the shape of the humidity versus time characteristic. The parameters are analyzed by a neural network to estimate a degree of doneness of the food. A controller uses the degree of doneness to estimate the remaining cooking time and appropriate power level. The cooking apparatus then operates in an open loop mode for the remainder of the cooking time using the appropriate power level.

Abstract: A heating body includes a layered structure consisting of a resistive body and a control body, with a meltable insulating sheet therebetween. The control body contains wires which are brought into electrical contact with the resistive body if the temperature of the resistive body exceeds the melting temperature of the insulating sheet. Current flow between the resistive body and the control body is detected to trigger a power cutoff to the resistive body. The material of the insulating sheet is selected to have a melting point well below an ignition temperature of the materials in the heating body, thereby triggering power cutoff at temperatures low enough to prevent fire. A control system normally controls the temperature of the heating body between an upper and a lower limit.

Abstract: A control device for heating elements, particularly for use in household electrical appliances such as cookers, cooking hobs, ovens and the like, comprising a driven switch in series with the, a first capacitor acting as a filter in parallel with the load, a second capacitor acting as a freewheeling capacitor operationally in series with the load and with the capacitor, these two being connected in parallel, and at least one inductor means in series with the load, characterised in that: a) the driven switch is a static switch hence able to assume an open state and a closed state; b) an inductor is provided in parallel with the load, or alternatively a section of the inductor means is in parallel with the load; c) a freewheeling diode is provided connected between an intermediate point between the inductor or section and freewheeling capacitor and an intermediate point between the load and static switch, so that when the static switch is in one state the freewheeling capacitor is charged via the freewheeling d