JP2847837B2 - Pot for induction heating cooker and induction heating cooker - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an induction heating cooker provided with a temperature display means and an induction heating cooker provided with a temperature control means using the induction heating cooker pot.

2. Description of the Related Art The configuration of a conventional induction heating cooker will be described with reference to FIGS. 4 and 5. FIG.

A pan mounting table 42 is provided on the upper surface of the outer housing 41, and the pan 43 is mounted thereon. A high-frequency current is supplied to the heating coil 46 from the inverter circuit 44 and its control unit 45, and an eddy current is generated in the pan 43 by the high-frequency magnetic field generated at that time, and the pan 43
Is to be heated.

In addition, the pot temperature display means 47 is usually arranged at a position on the side surface of the outer casing 41 and also serves as the pot temperature setting means. Also hot pot
For the temperature of 43, a configuration is often used in which a temperature sensor 84 such as a thermistor is brought into contact with the lower surface of the pot mounting table 42 to indirectly detect the pot temperature.

Problems to be Solved by the Invention In such a conventional induction heating cooker, the temperature of the pot 43, which is the object to be heated, is indirectly detected via the pot mounting table 42, so that the temperature of the pot 43 itself is Cannot be displayed,
In addition, there is a drawback that the response to the temperature change of the pot 43 seen when the food is put into the pot 43 is poor, and that the detection accuracy varies greatly.

The present invention solves the above-mentioned problems, accurately displays the temperature of the pot itself, enables easy temperature recognition even during cooking, and improves operability as a cooker without requiring an external drive power supply. It is a first object of the present invention to obtain a pot for an induction heating cooker. A second object of the present invention is to provide an induction heating cooker capable of performing high-accuracy and high-sensitivity temperature control by controlling the temperature based on the pot temperature detected by the induction heating cooker pan.

Means for Solving the Problems In order to achieve the first object, the present invention provides a work coil made of a conductive material disposed on the side of a pot, and a DC power supply for rectifying and smoothing a voltage induced in the work coil. Forming means, temperature detecting means for detecting the temperature of the pan, and temperature display means for displaying the temperature of the pan in accordance with the output of the temperature detecting means, wherein the temperature detecting means and the temperature displaying means are DC by the DC power source forming means. A first problem-solving means is that an induction heating cooker pot is driven by a power supply.

In order to achieve the second object, a control circuit for supplying an on / off signal to a semiconductor switching element in an inverter circuit, and a pot temperature level signal output from the induction heating cooker pot are sent to the control circuit. A temperature transmitting unit for transmitting the temperature of the pot, and a temperature setting circuit for setting the temperature of the object to be heated, the control circuit comprising: A second object of the present invention is to provide an induction heating cooker in which the timing of an on / off signal supplied to the semiconductor switching element is varied so as to reach a temperature set by a circuit.

According to the first aspect of the present invention, the pot temperature detecting means can be directly disposed at a position where the temperature of the pot itself can be detected, and can be mounted on a part of the pot main body in the temperature display. These drive sources do not need to be provided separately by utilizing the energy from the heating coil. Further, according to the second problem solving means, the temperature of the pan can be directly detected without any inclusions such as the pan mounting table, and the temperature of the pan can be controlled by the temperature signal level.
Highly accurate and sensitive temperature control is possible.

Embodiment An embodiment of the first invention will be described below with reference to FIG. 1 and FIG.

The pot 1 is formed of a pot material 2 containing a magnetic material, and a handle 3 is provided. The work coil 4 is wound around the side of the pot 2 and is insulated from the pot 2 by an insulating material 5. A circuit block 8 including a DC power supply forming means 6 and a temperature detecting means 7 and a temperature display means 9 are provided in the handle 3, and a temperature sensor 10 is disposed at the bottom of the pan. The work coil 4 is connected to the heating coil 12 below the pan mounting table 11.
It is arranged at a position substantially parallel to. The induced voltage generated in the work coil 4 is rectified by the rectifier 13 in the DC power supply forming means 6, and the energy is stored in the smoothing capacitor 14. On the other hand, the temperature sensor 10 using a thermistor etc.
Is directly received, and the signal is transmitted to the temperature detecting means 7. The temperature detecting means 7 uses the voltage between the terminals of the smoothing capacitor 14 as a power source, detects the temperature of the pot 1 by a signal from the temperature sensor 10, and outputs the result to the temperature display means 9. The temperature detecting means 7 also outputs the detected temperature level signal to the outside.

To explain the operation in the above configuration, the temperature detecting means 7 can directly detect the temperature of the pan 1 by a signal from the temperature sensor 10 which directly receives the temperature of the pan 1 and can display the temperature on the temperature display means 9. The temperature of the pot 1 itself can be accurately displayed, and the temperature can be easily recognized even during cooking. Further, since the temperature detecting means 7 and the temperature display means 9 are driven by the DC power supply by the DC power supply forming means 6, no external driving power supply is required, and the operability as a cooking appliance can be improved.

Next, an embodiment of the second invention will be described with reference to FIG. In FIG. 3, an inverter circuit 16 housed in an electromagnetic cooker main body 15 converts a commercial power supply 17 into a rectifier.
Full-wave rectification at 18 and choke coil on the output side of rectifier 18
19.A series circuit of a high-frequency bypass capacitor 20 is connected, and a parallel circuit of a resonance capacitor 21 and a heating coil 12, a switching transistor 22 and a freewheel diode 23 are connected between both ends of the high-frequency bypass capacitor 20.
Are connected in series.

When a high-frequency current generated by turning on and off the switching transistor 22 is supplied to the heating coil 12, the pot 1 placed near the heating coil 12 is induction-heated.

On the other hand, the pan temperature level signal output from the temperature detecting means 7 provided in the pan 1 is transferred to the receiving circuit 26 in the control circuit 25 via the temperature transmitting means 24.

The control circuit 25 includes the receiving circuit 26, a temperature setting circuit 27 for setting the pot temperature, and the pot temperature signal level value received by the receiving circuit 26 and the pot temperature setting value set by the temperature setting circuit 27. A comparison circuit 29 for comparing and comparing the magnitude relation to a heating power setting circuit 28, a timing circuit 30 for varying the ON time ratio of the switching transistor 22 according to the output of the heating power setting circuit 28, and a timing circuit 30 based on the output. And a drive circuit 31 for driving the switching transistor 22 on and off. Here, as the temperature transmitting means 24, those using infrared rays and those using high-frequency carriers can be used.

The operation of the above configuration will be described. The pan temperature level signal output from the temperature detecting means 7 provided in the pan 1 is transmitted to the receiving circuit 26 in the control circuit 25 via the temperature transmitting means 24.
Is transferred to this pot temperature signal level value and temperature setting circuit 27
The comparison circuit 29 compares the pan temperature set value set in the above with the comparison circuit 29, and inputs the output of the comparison circuit 29 to the heating power setting circuit 28. The heating power setting circuit 28 reduces the output of the heating coil 12 when the pan temperature signal level value is larger than the pan temperature set value, and conversely, decreases the output of the heating coil 12 when the pan temperature signal level value is small. The ON time ratio of the switching transistor 22 is changed so as to increase, and the temperature of the pan 1 is controlled. Therefore, highly accurate and highly sensitive temperature control can be performed.

As is clear from the above embodiments, the induction heating cooker pan of the present invention can accurately display the temperature of the pan itself, and by attaching it to a part of the pan, the temperature can be easily recognized even during cooking. Since a separate driving power source is not required for this purpose, no troublesome wiring is required, and the operability as a cooking appliance is improved.

Furthermore, since the induction cooking device of the present invention directly detects the temperature of the pot and controls the temperature, the temperature control accuracy and
Responsiveness to a temperature change is also improved, and a failure in tempura cooking or the like, which depends on the temperature, can be prevented beforehand, and a cooker that is easy for a cook to use can be provided.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a pot for an induction heating cooker according to one embodiment of the present invention, FIG. 2 is a block circuit diagram of the embodiment, FIG. 3 is a block circuit diagram of another embodiment of the present invention, FIG. FIG. 4 is a longitudinal sectional view of the conventional example, and FIG. 5 is a perspective view of the conventional example. 1 ... Pot, 4 ... Work coil, 6 ... DC power supply forming means, 7 ... Temperature detecting means, 9 ... Temperature display means, 12 ...
Heating coil, 16: Inverter circuit, 22: Switching transistor (semiconductor switching element), 24:
Temperature transmitting means, 25 control circuit, 26 receiving circuit, 27
... Temperature setting circuit.

Claims (2)

(57) [Claims] 1. A work coil made of a conductive material disposed on a side of a pot, a DC power supply forming means for rectifying and smoothing a voltage induced in the work coil, a temperature detecting means for detecting a pot temperature, and the temperature detection. A pot for an induction heating cooker, further comprising temperature display means for displaying a pot temperature according to an output of the means, wherein the temperature detection means and the temperature display means are driven by a DC power supply by the DC power supply forming means. 2. A heating coil for heating an object to be heated by induction heating, an inverter circuit for supplying a high-frequency current to the heating coil, and a control circuit for supplying an on / off signal to a semiconductor switching element in the inverter circuit. And a temperature transmitting means for transmitting a pan temperature level signal output from the induction heating cooker pan to the control circuit, wherein the pan temperature level signal output from the temperature transmitting means is transmitted to the control circuit. A receiving circuit for receiving and a temperature setting circuit for setting a temperature of the object to be heated are provided, and a timing of an on / off signal supplied to the semiconductor switching element is varied so as to reach a temperature set by the temperature setting circuit. Induction heating cooker made like this.