Abstract: A monitor device for creating a current signal having a voltage representative of the instantaneous alternating current in an induction heating coil connected to an alternating current supply by two closely spaced, parallel input conductors separated by a narrow gap or flux package through which flows the flux created by the alternating current in the parallel conductors. The monitor device comprising: a multiturn sensing winding, means for securing the winding between said parallel conductors and over the flux passage whereby the flux flowing through flux passage intersects the turns of the sensing winding, and means for creating the current signal by the induced voltage in the winding.

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 dual push-pull induction heating drive circuit comprises an oscillation triggering control circuit regulating the ON-OFF switch of the circuit activation, a switching logic circuit bringing about two exclusive pulse signals serving to drive via an amplifying circuit a dual push-pull switching output circuit having two power elements connected to an induction coil, a pulse width modulating circuit having a controlled comparing element capable of sending out adjustable pulse, and a synchronous detection comparing circuit having at least a comparing element and having an input end in communication with an induction coil and another input end connected with a power source and further having an output end connecting with the switching logic circuit and sending out synchronous pulse signals to a differentiation circuit to bring about synchronous differentiation pulse signals, which are received by the pulse width modulating circuit so as to generate the power control pulse signals serving via the switching logic

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: An induction heating cooker has a rectifier (13) for producing pulsating DC current, an inverter (14) which receives the pulsating current given from the rectifier (13) and produces a high frequency output current and a load circuit (15) including an output coil (21) and a resonance capacitor (22) connected in series to each other to receive high frequency output signal from the inverter, and the variation or adjustment of output electromagnetic power is made by changing duty ratio of the high frequency output current of the inverter by giving variable duty ratio setting signals to switching elements (Qa, Qb) in the inverter 14; the frequency of the high frequency output current of the inverter 14 is fixed, and therefore, unpleasant interference sound is not generated at parallel simultaneous operation.