JPS61292878A - Output control circuit for electromagnetic 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 output control circuit for an electromagnetic cooker that controls cooking temperature by intermittent operation of the electromagnetic cooker using an LSI for frequency control. It is something.

[Prior art]

As shown in FIG. 3, the output control circuit of a conventional electromagnetic cooker is a frequency control LSII that has an A/D conversion function for converting a voltage according to the temperature setting of a variable resistor 10 for setting the cooking temperature.
A signal of a frequency corresponding to the digital signal inputted to the A/D conversion section of the I and outputted from the A/D conversion section is generated, and this signal is added to the inverter to operate the electronic cooking appliance.

The relationship between the temperature setting of the variable resistor 10 and the input voltage of the A/D converter of the LSIII is proportional as shown in FIG. For example, when the temperature setting of the variable resistor 10 is tempura, the input voltage of the A/D converter of the LSIII is 4.
The voltage becomes 6 to 5V, and the inverter is driven by a signal of a frequency corresponding to the digital signal of this voltage, and the tempura oil is heated. At this time, temperature control using a thermistor allows
The temperature of tempura oil is kept constant. .

However, with the above-mentioned conventional structure, when used in a foreign country where a 200V power supply is used, for example, the power supply voltage is high, so a small power of 200W or less, which is a low temperature setting, cannot be obtained. For this reason, in countries with such power supply conditions, the cooking temperature is controlled by using an LSI for intermittent control and causing the electromagnetic cooker to operate intermittently. However, in order to manufacture in Japan an electromagnetic cooker that can be used even in countries with the above-mentioned power supply conditions, it is necessary to develop an LSI for the above-mentioned intermittent control, which requires enormous costs and costs to develop this LSI. There are problems such as the number of days required.

[Purpose of the invention]

The present invention has been made in consideration of the above-mentioned conventional problems, and is an LS for frequency control normally used in Japan.
The purpose of this invention is to provide an output control circuit for an electric VTM controller that can be adapted to overseas power supply conditions without requiring the development of a new LSI by effectively utilizing I.

[Structure of the invention]

The output control circuit for an electromagnetic cooker according to the present invention includes an output voltage from a variable resistor for setting the temperature of the electromagnetic cooker;
An LSI input voltage control circuit that compares the reference voltage obtained by the voltage dividing resistor and inputs the higher voltage to the next stage frequency control LSI, and operates the LSr according to the output voltage of the variable resistor. and a frequency I that performs A/D conversion on the input terminal from the LSI input voltage control circuit and generates a signal with a frequency corresponding to the digital signal.
This device is characterized in that it is equipped with an LSI for Q-use, and can perform intermittent control of the electromagnetic cooker by effectively utilizing the LSI for frequency control.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 shows the configuration of the output control circuit of the electromagnetic cooker of this embodiment. A variable resistor 2 is provided on the power supply side of the LSI input voltage control circuit 1. This variable resistor 2
This allows you to freely change the temperature setting from the highest temperature for tempura to high, medium, and low, depending on the cooking temperature in an electromagnetic cooker or a rice cooker.

The variable resistor 2 is provided with an intermediate terminal 2a for dividing and supplying the power supply voltage for the output control circuit according to the temperature setting. This intermediate terminal 2a and an L for frequency control provided at the next stage of the LSI input voltage control circuit 1
S) Between the A/D converter of 8 and the intermediate terminal 2a, L is connected.
The diode 3 is connected with the SI8 direction as the forward direction. A voltage dividing resistor 4 and a voltage dividing resistor 5 connected in series are connected in parallel to the variable resistor 2 for dividing the power supply voltage for the output control circuit and setting a reference voltage. The connection part 6 of the voltage dividing resistor 4 and the voltage dividing resistor 5 and the A/
A diode 7 is connected between the D conversion parts with the forward direction being from the connection part 6 to the LSI 8 direction. An intermittent circuit 9 for intermittent control of the operation of the LSI 8 is connected between the LSI 8 and the intermediate terminal 2a of the variable resistor 2.

In the above configuration, when cooking tempura with the electromagnetic cooker, the variable resistor 2 of the LSI input voltage control circuit 1 of the output control circuit is operated to adjust the temperature setting to the temperature of the tempura. At this time, if the voltage between the intermediate terminal 2a of the variable resistor 2 and the ground is 2, and the voltage serving as the reference voltage between the connection part 6 and the ground is v2, then the voltage dividing resistor 4 is set so that V,>V.・5 has been adjusted. This allows the voltage above
1 is applied to the A/D converter of the LSI 8 via the diode 3 and converted into a digital signal. And LSI
8 generates a signal with a frequency corresponding to the digital signal, and this signal is applied to the next stage inverter to heat the tempura oil. At this time, the operation of the intermittent circuit 14 is stopped and the LSIB is operated in a constant state, but the temperature of the cooking oil is kept constant by a thermistor (not shown) having a temperature compensation function. Further, when the above temperature setting is for tempura, as shown in FIG. 2, V,>V.

By changing the voltage v1 within the range of , the voltage applied to the LSI 8 can be varied, and the temperature of the cooking oil can be adjusted by 'df1.

On the other hand, when cooking at high, medium, or low temperature settings other than the above-mentioned tempura, use the voltage (2) mentioned above.

The relationship between the reference voltage ■2 and the reference voltage ■2 is configured such that ■,≦■2. As a result, the reference voltage v2, which is a constant voltage, is applied to the A/D converter of the LSI 8 via the diode 7, regardless of the temperature setting by the variable resistor 2. This reference voltage (2) is processed by the LSI 8 in the same manner as in the case where the temperature setting is set to tempura. At this time,
The intermittent circuit 14 operates in response to the output voltage from the variable resistor according to the temperature setting, and the output of the LSI 8 is controlled to be intermittent. The output of this LSI 8 is input to the next stage inverter to operate the electromagnetic cooker intermittently and control the cooking temperature.

〔Effect of the invention〕

The output control circuit for an electromagnetic cooker according to the present invention utilizes a commonly used LSI for frequency control as an LSI of a control circuit for driving an inverter of an electromagnetic cooker that controls cooking temperature through intermittent operation. The structure is such that this LSI is operated intermittently according to the temperature setting of the variable resistor using an intermittent circuit. For this reason, a new LS for intermittent control has been added.
It can be applied to overseas power supply situations without developing I. Further, it is possible to suppress the cost increase that tends to occur due to the cost and the number of days required to develop the LSI for frequency control. Furthermore, since the LSI input voltage control circuit is constructed of a simple circuit with a very small number of parts, it has advantages such as high reliability.

[Brief explanation of the drawing]

FIG. 1 is a schematic circuit diagram showing an embodiment of the present invention, and FIG. 2 is an LSI circuit diagram for temperature setting of the variable resistor shown in FIG.
3 is a schematic circuit diagram showing a conventional example, and FIG. 4 is a graph showing the A/D converter input voltage of the LSI with respect to the temperature setting of the variable resistor shown in FIG. 3. It is a graph showing voltage. 1 is an LSI input voltage control circuit, 2 is a variable resistor, 2a is an intermediate terminal, 3 and 7 are diodes, 4 and 5 are voltage dividing resistors, 6
8 is an LSI, and 9 is an intermittent circuit.

Claims (1)

[Claims] 1. Compare the output voltage from the variable resistor for setting the temperature of the electromagnetic cooker with the reference voltage obtained from the voltage dividing resistor, and input the higher voltage to the next stage frequency control LSI. An LSI input voltage control circuit, an intermittent circuit that controls the operation of the LSI intermittently according to the output voltage of the variable resistor, and an input voltage from the LSI input voltage control circuit 1
An output control circuit for an electromagnetic cooker, comprising a frequency control LSI that performs D conversion and generates a signal with a frequency corresponding to the digital signal.