JPH0422557Y2 - - Google Patents

Description

[Detailed Description of the Invention] A. Field of Industrial Application The present invention relates to an induction heating cooker that automates stewing cooking.

B. Prior Art An induction heating cooker generates a high-frequency current in an induction heating coil, generates a high-frequency alternating magnetic field from the induction heating coil, and inductively heats cooking utensils placed close to the induction heating coil. In such an induction heating cooker, for example,
As shown in No. 10837, there were devices that controlled output and temperature.

C. Problems to be solved by the invention However, in such an induction heating cooker, the set temperature and set input are always kept constant. For this reason, when boiling the food in the cooking utensil at high input and then stewing at low input, the user must confirm that the food has boiled before reducing the heating output. It didn't happen.

An object of the present invention is to provide an induction heating cooker that can reliably and automatically perform a continuous operation of boiling the food and then simmering the food at a low output.

D. Means for Solving the Problems The induction heating cooker of the present invention includes an input setting means for setting the heating input, a temperature detection means for detecting the temperature of the cooking utensil to be heated, and a temperature detection means for detecting the temperature of the cooking utensil to be heated. It has a timer means for starting a timer operation according to the temperature, and an input switching means for reducing the setting input in the input setting means after a predetermined delay in the timer means.

E. Effect: After the food is reliably boiled, the food is automatically simmered at low output, thereby simplifying the simmering process.

Embodiment Figure 1 shows a circuit block diagram of an embodiment of the induction heating cooker of the present invention, in which 1 is a full-wave rectifier circuit for full-wave rectifying AC power supply, 2 is a choke coil, 3 is a smoothing capacitor, and 4 is a It is an induction heating coil connected to the full-wave rectifier circuit 1 via the above-mentioned chiyoke coil 2, and a cooking utensil 5 such as a pot is placed close to the induction heating coil via the top plate T. 6 is a resonant capacitor forming a resonant circuit with the induction heating coil 4; 7 is a switching transistor connected in series with the induction heating coil; and 8 is a diode connected antiparallel to the switching transistor 7. 9 is an input power detection circuit that detects input power by detecting the AC input current detected by the current transformer 10; 11;
1 is an input setting means for setting the input power; 12 is a comparator for comparing the signal from the input setting means 11 with the signal from the input power detection circuit 9; and 13 is for controlling ON/OFF of the switching transistor 7.
It is an ON/OFF control circuit, and adjusts the ON time based on the signal from the comparator 12. Reference numeral 14 denotes temperature detection means comprising a thermistor 15, a comparator 16, etc. The thermistor 15 detects the temperature of the cooking utensil 5 and changes its resistance value. 17
indicates a switching control circuit which obtains the output from the comparator 16, which one of the resistors 18 and 19 provided in parallel with the input setting means 11 is selected by turning ON and OFF the transistors Tr1 and Tr2; The setting input level given to the comparator 12 is switched. 20 is a switch for operating this switching control circuit 17; 21 is a switch for operating this switching control circuit 1;
7 and counts the delay time. Reference numeral 22 denotes a notification circuit connected to the switching control circuit 17 and performing notification operations such as sounding a buzzer in response to switching operations of the switching control circuit 17.

In such an induction heating cooker, during normal input control operation, the set level in the input setting means 11 and the signal from the input power detection circuit 9 are compared, and "H" and "L" signals are output from the comparator 12. be done. ON,
The OFF control circuit 13 controls the ON time length of the switching transistor 7 and adjusts the input based on the ratio of "H" and "L" from the comparator 12.

On the other hand, when stewing dishes such as stew are to be performed fully automatically, the setting level of the input setting means 11 is set to the low level side and the switch 20 is turned on. This causes the switching control circuit 17 to switch the transistor Tr1.
Turn on and turn off transistor Tr2. As a result, the level applied to the comparator 12 via the low resistance value resistor 18 becomes a high level corresponding to 1300W heating. At the same time, the switching control circuit 17
1 for a delay of 2 minutes, after which the temperature detection signal from the comparator 16 can be detected. When the cooking utensil 5 is heated by the 1300W heating setting in the switching control circuit 17 and a predetermined temperature a° (for example, 95°C) is detected by the set temperature detection circuit 14, the switching control circuit 17 uses the timer circuit 21 to start cooking. After a delay time necessary for the substance to boil sufficiently, for example 2 minutes, transistor Tr1 is turned off, transistor Tr2 is turned on, and a low level corresponding to 250W heating is sent to comparator 12 via high resistance value resistor 19. A signal is given and stew cooking starts. At the same time, the switching control circuit 17
sends a signal to the notification circuit 22, which causes notification by a buzzer or the like. FIG. 2 shows the simmering operation of such a cooker.

Figure 3 is a diagram showing the relationship between heating input, detected temperature, and food temperature when stewing is started from the initial state, and Figure 4 is a diagram showing the relationship between heating input, detected temperature, and food temperature when stewing is started from the initial state. heating input when
It is a figure showing the relationship between detected temperature and cooked food temperature.

G. Effects of the invention According to the induction heating cooker of the invention, the input setting means for setting the heating input, the temperature detection means for detecting the temperature of the cooking utensil to be heated, and the and input switching means for reducing the setting input in the input setting means after a predetermined delay by the timer means, so that the cooking time can be adjusted after the food has boiled. Things can be boiled automatically at low output, simplifying stewing cooking.

Furthermore, the temperature detection means detects the temperature of a cooking utensil such as a pot, and even if the detected temperature reaches the boiling temperature, the temperature of the food in the cooking utensil may not yet reach the boiling temperature. In view of this, after the temperature detection means reaches the boiling temperature, the temperature of the food to be cooked is delayed for a predetermined period of time so that the temperature of the food to be cooked reaches the boiling temperature during this time. It is possible to reliably bring the cooked food to a boil, and the finished condition of the stew can be improved.

[Brief explanation of the drawing]

Figure 1 is a circuit block diagram of the induction heating cooker of the present invention, Figure 2 is a flowchart showing the operation of the induction heating cooker of the present invention, and Figures 3 and 4 are switching inputs during operation of the induction heating cooker of the present invention. It is a characteristic diagram which shows the relationship between detected temperature, and the temperature of a cooked object. 1...Full wave rectifier circuit, 4...Induction heating coil,
6... Resonance capacitor, 7... Switching transistor, 8... Diode, 9... Input power detection circuit, 11... Input setting means, 12, 16...
Comparator, 13...ON, OFF control circuit, 14...
Temperature detection circuit, 17...Switching control circuit, 18, 1
9...Resistor, 20...Switch, 21...Timer circuit.

Claims (1)

[Scope of utility model registration request] An input for setting the heating input in an induction heating cooker that generates a high-frequency current in an induction heating coil, generates a high-frequency alternating magnetic field from the induction heating coil, and inductively heats metal cooking utensils placed close to the induction heating coil. a setting means, a temperature detection means for detecting the temperature of the cooking utensil to be heated, a timer means for starting a timer operation according to the temperature detected by the temperature detection means, and after a predetermined delay by the timer means;
An induction heating cooker comprising: input switching means for reducing the setting input in the input setting means.