JPS6193590A - Induction heating cooker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to an induction heating cooker for general household use.

Structure of a conventional example and its problems FIG. 1 shows a conventional example of an induction heating cooker. In FIG. 1, 1 is an AC power supply, 2 is a rectifier circuit, 3 is an inverter that generates high-frequency power, 4 is a fan motor that cools high-temperature parts in the induction heating cooker, 5 is a control circuit for the inverter 3, and 6 1 is a step-down switching regulator configured by a reactor and a switching circuit 8, and supplies power from a rectifier circuit 2 to a control circuit 5. In this conventional configuration, the reactor 7 is required, which increases the number of parts and increases the cost.Furthermore, the fan motor 4 also needs to be for high voltage, making the fan motor large and expensive. There was a problem.

OBJECTS OF THE INVENTION The present invention solves these conventional problems and provides an induction heating cooker that has a small number of parts and is low in cost.

Composition of the Invention The induction heating cooker of the present invention includes a rectifier circuit, an inverter connected to the rectifier circuit to generate high-frequency power, a control circuit for the inverter, a fan motor, and a control circuit from the output of the rectifier circuit. The fan motor has a step-down switching regulator that supplies power to the circuit, and part or all of the reactor of the step-down switching regulator is the winding of the fan motor. This reduces the number of parts and costs without providing a separate reactor.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. In Fig. 2, 11 is an AC power supply, 12 is a rectifier circuit, 13 is an inverter that is connected to the rectifier circuit 12 and generates high-frequency power, 14 is a fan motor that cools the high-temperature parts in the induction heating cooker, and 15 is an inverter. 13 is a control circuit, and 16 is a step-down switching regulator that is constituted by the winding of the fan motor 14 and a switching circuit 17, and supplies power to the control circuit 1 from the output of the rectifier circuit 12. In the embodiment, all of the windings of the fan motor 14 are used as the reactor of the step-down switching regulator 16, but it is clear that only a part of the windings may be used.

To explain the operation in the above configuration, the fan motor 14
The winding works with the reactor of a drop-down switching regulator, so the number of parts can be reduced, the cost can be lowered, and a small and inexpensive fan motor for low voltage can be used. .

FIG. 3 shows a further specific example thereof. In FIG. 3, the switching circuit 17 includes the switching transistor 3
o, its drive resistor 31, resistor 32, Zener diode 33, resistor 34 for supplying current to Zener diode 33, and transistor that compares the voltage of Zener diode 33 with the output voltage and drives switching transistor 30. 35, a resistor 36 that causes hysteresis, a resistor 37, and a flywheel diode 38.
The power supply voltage of the control circuit 15 is kept almost constant, and current is also supplied to the fan motor 14.

Effects of the Invention As is clear from the above embodiments, the induction heating cooker of the present invention has a reduction in the number of parts, especially by using the fan motor winding for part or all of the reactor of the drop-down switching regulator. The cost is low and the fan motor can be made smaller.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing a conventional induction heating cooker, FIG. 2 is a circuit diagram of an induction heating cooker showing an embodiment of the present invention, and FIG.
The figure is a circuit diagram of an induction heating cooker showing a specific embodiment of the present invention. 12... Rectifier circuit, 13... Inverter, 15... Control circuit, 14... Fan motor, 16... Step-down switching regulator . Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2

Claims (1)

[Claims] It has a rectifier circuit, an inverter connected to the rectifier circuit to generate high-frequency power, a control circuit for the inverter, a fan motor, and a step-down switching regulator that supplies power from the output of the rectifier circuit to the control circuit. and an induction heating cooker in which part or all of the reactor of the step-down switching regulator is the winding of the fan motor.