Abstract: A control device particularly for induction cooking ranges with multiple heating units which comprises a plurality of induction coils. The induction coils can be electrically parallel-connectable to each other. The device also comprises elements for engaging the induction coils connecting individual induction coils or pairs of induction coils to a single electric power converter, and elements for sensing the presence or the absence of a pot or the presence of an unadapted pot on a particular induction coil; the sensor elements are electrically connected to control means that select, on user's command, the induction coils to be activated and the power to be carried to each individual induction coil, and control the sending of shares of the power generated by the electronic converter to each active induction coil, at the same time limiting the periodic variations in the current absorbed from the mains, within the limits allowed by statutory provisions regarding so-called "flicker".

Abstract: The present invention relates to an induction heating cooker for supplying a predetermined resonant current to a heating coil to thereby carry out a cooking operation, the induction heating cooker including: a rectifying unit for full wave rectifying a commercial alternating current, a zero voltage detecting unit for detecting a zero potential of the commercial alternating current, a control unit for synchronizing with the zero potential of the commercial alternating current detected by the zero voltage detecting unit to thereby control the overall operations of the induction heating cooker, a variable frequency oscillating unit for receiving a control signal generated by the control unit to thereby generate an oscillating frequency, an inverter driving unit for generating a driving signal to thereby drive the switching element according to the oscillating frequency generated by the variable frequency oscillating unit, an inverter for receiving the direct current voltage generated from the rectifying unit acc

Abstract: An induction cooking heater includes at least one inductor, a high-frequency current generator and a magnetic circuit located beneath the inductor. The reluctance of the magnetic circuit is calibrated so that the magnetic circuit gets saturated from a predetermined temperature lower than the maximum permissible temperature for the inductor. A plate made of non-magnetic, electrically conductive material located beneath the magnetic circuit, gives rise to an increase in current in the inductor when the magnetic circuit starts getting saturated. The generator is then controlled by a regulator for limiting the value of the current in the inductor to deliver lower power to the inductor.

Abstract: An induction cooking apparatus and method for inductively heating cookware is provided. An analog/digital circuit, including a microprocessor, generates a plurality of gating pulses for operating the power inverter circuit and monitors the operation of the power inverter circuit. The microprocessor provides signals to start and stop the inverter circuit, and determines a period of uninterrupted power inverter circuit operation corresponding to a desired cooking temperature. Analog circuitry is provided for sustaining operation of the power inverter circuit after the power inverter circuit is started, and for compensating for variations in cookware materials.

Abstract: This invention relates to a process and a device for controlling power for a circuit comprising a resonant inverter intended to supply a variable impedance load comprising an inductive component. The invention renders the active power consumed by the load independent of the nature of the load by producing an error signal that is a function of an average value of a current passing through power transistors of the inverter, this error signal being used to control a power modulator controlling the switching of the power transistors. Such a process and device finds particular application to a circuit for controlling power supplied to an inducer and a cooking utensil.

Abstract: In a switching device of an induction heating cooker, an oppositely poled diode for conducting a reverse current is coupled across the collector-emitter portion of a switching element provided in the first switching device, and turn-ON operation of the switching devices does not OCCUR in normal operation of the DUTY FACTOR T.sub.2 /T.sub.1 .apprxeq.0.5.

Abstract: An apparatus for sensing a small object in a high-frequency induction heating cooker, comprising a rectifying/smoothing circuit for rectifying and smoothing an AC voltage from a power source to convert it into a DC voltage, an inverter for converting the DC voltage into a high frequency of AC voltage, a heating coil for generating an induced current according to the AC voltage from the inverter, a synchronization detector for detecting a synchronization signal, a current detector for detecting an amount of current through the rectifying/smoothing circuit, a voltage detector for detecting a voltage from a desired position of the inverter, a small object sensing circuit for discriminating presence of the small object in a cooking container in response to output voltages from the current detector and the voltage detector, a clock generator for generating a clock signal for system synchronization, a pulse generator for generating a pulse signal in response to output signals from the clock generator and the small

Abstract: A high frequency induction heating appliance comprising a working coil for generating a high frequency signal, a switching device for switching a drive voltage to the working coil, a low voltage transformer for lowering an AC power voltage, an input current detector for detecting current of the AC power, an output adjusting device for providing an output adjusting signal, a differential amplifier for amplifying a difference between output signals from the input current detector and output adjusting device, a first comparator for comparing the output signal from the input current detector with a reference voltage, an integrator for integrating an output signal from the differential amplifier, a start signal generating circuit, a zero crossing detecting circuit, a delay circuit for delaying a zero crossing detect signal by a time period, an AND logic operating circuit for AND logic-operating a start signal and the delayed zero crossing detect signal, a synchronizing signal generator, a reference signal generato

Abstract: A circuit for compensating for the output of a high frequency induction heating cooker, comprising a rectifying circuit for rectifying an external AC input power into a DC power and applying the DC power to a working coil, an output regulation signal generating circuit for generating an output regulation signal as a result of the comparison of an input voltage and an output regulation voltage, a start driving circuit for generating a start drive voltage, a triangular wave generating circuit being triggered in response to a driven state of the working coil to generate a triangular wave signal, a switching circuit for start-driving the working coil in response to the start drive voltage, comparing the output regulation signal with the triangular wave signal and switching the driving of the working coil in accordance with the compared result, a voltage detecting circuit for detecting a voltage being applied from the rectifying circuit to the working coil and inversion-amplifying the detected voltage, an output c

Abstract: A high frequency cooker which detects a sound generated upon boiling of a material to be heated in response to the material being heated and switch as to a cooking mode in response to the detected signal of that sound. The cooker comprises a heating section for heating a material to be heated, a sensor for detecting a sound generated from the material to be heated upon boiling of the material to be heated, and a control section for controlling the heating section in response to the detected sound. The cooker can sense the sound of the material to be heated and can switch automatically from a cooking mode to a warm mode even by only making a single function selection. An optimum cooking state of the food can be maintained, and unnecessary power loss can also be prevented.