摘要:
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 control unit for generating output regulation data according to a user's selection, and a voltage dividing circuit for dividing an output voltage from the voltage detecting circuit according to the output regulation data and outputting the divided voltage as the output regulation voltage.
摘要:
A power control device for high-frequency induced heating cooker is designed to supply a constant power to the work coil regardless of any change in the input current and voltage. The control device compares the voltage detected at the input current sensor detecting the input current of the full-wave rectifier with the set voltage of the user selector and applies a control voltage to the pulse oscillator and applies the pulse oscillating signal of the pulse oscillator to the driver and makes the switching transistor rapidly turn on and off to generate a high-frequency current through the work coil. It includes a voltage sensor to detect the input and output voltages of the coil, a comparator to compare both detector voltages and to determine the drive starting point of the oscillator, a subtractor to subtract the voltage on the input side of the work coil from the set voltage of the user selector, a comparator to compare the voltage detected at the input current sensor with the normal vessel reference voltage, a transistor to cut off the control voltage applied to the pulse oscillator, a search control voltage part to produce a search control voltage of a constant level and a starting circuit part to generate an oscillation signal of a constant cycle, and a transistor turned on and off by the oscillation signal and supplies the search control voltage to the pulse oscillator in a constant period.
摘要:
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 generator, a second comparator for comparing an output signal from the AND logic operating circuit with a reference signal or comparing an output signal from the integrator with the reference signal, and a drive controller for controlling the operation of the switching device in response to an output signal from the second comparator.
摘要:
A foldable shock absorbing seat for industrial vehicles comprises a seat member; a back member extending upwardly from a rear end of the seat member; a first folding joint for allowing the back member to be folded relative to the seat member; a frame for supporting the seat member and the back member; a second folding joint provided on the frame for enabling the frame to be folded as the back member is folded toward the seat member; and a unit for absorbing shock inflicted on the seat member and the back member, and shock absorbing unit disposed between the frame and the seat and back members.
摘要:
A high frequency heating apparatus has an output controlling function to prevent breakdown of the switching element in an invertor circuit, while also eliminating noise generated by the frequency changes caused by the various consumption power signals generated. A microprocessor produces a consumption power change signal according to the user's preference, that activates a switching element, typically a solid-state component, as a function of the change signals produces. The inventive heating apparatus operates in an output control mode according to a particular duty cycle. A reference voltage is used with a comparator to produce a signal generating a pulse signal of variable width, according to the signals outputted from the microprocessor. The pulse width signals control the switching element to maintain a constant consumption power according to a particular duty cycle, thereby preventing the microprocessor output signals from adversely driving the switch element which leads to breakdown as a result of the undesirable noise generated due to the frequency change.