JPH0420308A - Heating cooker - Google Patents

Abstract

PURPOSE:To separately display the contents of abnormality so that its cause can be discriminated by constituting the cooker so that an abnormal state is displayed by a method being different from a regular display method at the time of abnormality, and also, determining one abnormality display method to one cause, and executing the synthesized display at the time when the cause extends over two. CONSTITUTION:An arbitrary set temperature t1 is selected by a temperature setting means 7, and a microcomputer 19 transfers its information to a temperature display means 6. The temperature display means 6 turns on a dot 81 corresponding to the selected temperature. However, when its contact is not closed due to a contact failure of a relay contact 12a, it is detected and the cooker is shifted to an abnormality display mode 2. On the contrary, when the relay contact 12 does not conform to an output signal (c) of the microcomputer 19 and is not opened, a collector terminal of a transistor 17 becomes a state that '0' voltage remains held, and by detecting it, the cooker is shifted to an abnormality display mode 3. In such a way, a parts failure is informed to a user without using specially a display means and danger of a failure of cooking can be prevented in advance.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a heating cooker equipped with a temperature adjustment function and means for displaying a set temperature.

Conventional technology Conventionally, a cooking device equipped with a heater as a heating means, for example, is equipped with a means for setting the temperature of the cooking container, and a relay or triac (bidirectional conduction The energization ratio to the heater is adjusted by turning on and off a thyristor, etc. Thermistors, which are inexpensive and easy to handle, are often used as temperature sensors that detect the temperature of cooking containers.

Problems to be Solved by the Invention However, in the conventional configuration, when the relay contacts are welded or the triac is short-circuited, the temperature of the cooking container reaches the set temperature and the control circuit tries to turn off these opening/closing means. The heater is continuously energized and the set temperature is exceeded. In addition, the lower the detected temperature, the higher the output resistance value of the thermistor becomes (3g), so it is difficult to distinguish the difference from the thermistor open failure, so the control circuit similarly operates the heater continuously. I'll take it to the power source. In this way, when there are multiple causes of continuous energization regardless of the instructions from the control circuit, there is a problem in that it is difficult to decide which part to inspect.

The present invention is intended to solve the above-mentioned problems, and includes a means for detecting an abnormality such as a disconnection of the opening/closing means or thermistor, and displaying the details of the abnormality individually using temperature display segments so that the cause can be determined. The purpose is to provide a heated cooking device.

Means for Solving the Problems In order to achieve the above object, the present invention utilizes a normally used temperature display segment, and is configured to display an abnormal state in a method different from the normal display method when an abnormality occurs. In addition, one abnormality display method is determined for one cause, and when two causes are present, a means is provided for displaying a composite display of the two causes.

Effects of the present invention With the above means, it is possible to know whether there is an abnormality just by looking at the normally used temperature display segment.

In addition, it is possible to immediately determine how many causes of the abnormality there are and which ones are the causes.

Example An embodiment of the present invention will be described below.

FIG. 1 shows an external perspective view of the cooking device main body. A doughnut-shaped heater 2, which is a type of heating means, is arranged above the outer shell 1. Then, the pot 3 is placed on the heater 2 and used for cooking.

There is a control circuit 4 inside, which controls the supply of electricity to the heater 2. The temperature of the pot 3 is detected by a temperature sensor 5. The temperature set by the temperature setting means 7 is displayed in a temperature display segment within the temperature display means 6.

FIG. 2 shows the overall circuit configuration of the control circuit 4. Commercial power supply 1
A relay contact 12a is connected to the heater 2 in series with the heater 2. The control circuit 4 is provided with a power source 13 for driving the DC chamber 5 and a DC power source 14 for driving the relay coil 12b. Transistor 1 through resistors 15 and 16
7 is turned on and off, an output signal (,) is output to the resistor 18, and the signal is input to the microcomputer 19.

Further, the divided voltage (1) of the thermistor 2o and the resistor 21 is input to the microcomputer 19. Note that at this time, as the temperature of the thermistor 20 increases, the divided voltage (b) also increases. The microcomputer 19 has a function of A/D converting the input divided voltage (1).

On the other hand, when turning on the relay contact 12 &, the microcomputer 19 drives the transistor 24 via the resistors 22 and 23 with the output signal (q).

When transistor 24 turns on, relay coil/L'12b
Current flows through, turning on relay contact 12a.

The diode 25 is connected in parallel with the relay coil (v12b) and protects the transistor 24 by absorbing the surge voltage generated in the relay coil 12a when the transistor 24 is off.

Furthermore, the temperature setting signal set by the temperature setting means 7 is input to the microcomputer 19, and its contents are output to the temperature display means 6.

FIG. 3 shows an embodiment of the temperature display means 7.

Six number blocks (71
~76), 6 each corresponding to one number block on the bottom row
Display segments of two dot blocks (77 to 82) are arranged.

The operation in the above configuration will be explained according to the fourth flowchart.

An arbitrary set temperature (tl) is selected by the temperature setting means 7 (the set value is now 180° C.), and the signal thereof is input to the microcomputer 19. The microcomputer 19 transmits the information to the temperature display means 6.

The temperature display means 6 displays a dot 81 corresponding to the selected temperature.
(See Figure 3). Next, read the divided voltage (b) of the thermistor 20 and resistor 21. At this time, if the thermistor 20 is disconnected, the voltage is (b) -0, so the mode shifts to abnormality display mode 1 at that time. Also, when the voltage is 0 (page 7), the voltage is A/D converted and read as the thermistor temperature (t2). In addition, the thermistor temperature (
When t2) has not yet reached the set temperature (tl)=180°C, the relay contact 12a is turned on, and when it has already been reached, it is turned off.

Thereafter, the waveform of the input signal (a) is checked.

First, when the relay contact 12a is on, the transistor 17 is off, and the input signal (=) is held at 0. However, relay contact 12a
When the contact is not closed due to a contact failure, 0 voltage is output to the collector terminal of the transistor 17 instead of the waveform pulse shown in Fig. 6(b), and this is detected and the mode shifts to abnormality display mode 2. do.

Further, when the relay contact 12a is turned off, the output signal (b) becomes "H" and turns off the transistor 24. The waveform of the input signal (a) is shown in FIG. 6(b).
It will be as shown in However, this time, the relay contact 12a receives the output signal (C) of the microcomputer 19.
When the transistor 17 is not opened in accordance with the above, the O voltage is maintained at the collector terminal of the transistor 17, and by detecting this, the abnormality display mode 3 is entered.

FIG. 6 shows an example of the lighting state of each display segment when transitioning to each abnormality display mode described above.

FIG. 5(a) shows that when the thermistor 2o is disconnected, the display segment 77 goes out and all other display segments are in a blinking state at the same time. In the same figure (b), the microcomputer 19 is connected to the relay contact 12.
This shows that when the relay contact 12a remains in the off state even though the relay contact 12a is turned on, the display segment 78 goes out and all other display segments flash at the same time. . In the same figure (C), when the relay contact 12a remains on even though the microcomputer 19 is turning off the relay contact 12a, the display segment 79 goes out and all other display segments blink at the same time. This shows that the status is In the same figure (→ shows that when the thermistor 2o is disconnected and the relay contact 12a remains on even though the microcontroller 9 page computer 19 turns off the relay contact 12a, the display segments 77 and 79 turn off. , all other display segments are shown flashing at the same time.

In this embodiment, a heater is used as the heating means, but a heating coil for induction heating may be used, for example, and any means for heating an object to be heated such as a pot may be used.

Effects of the Invention As is clear from the above embodiments, according to the present invention, when the control circuit detects a component defect, the temperature display segment in the temperature setting means is used to perform a different display method than usual. It is possible to notify a user of component defects without using a separate display means and prevent the risk of cooking failure. Furthermore, it is possible to provide a cooker that can be notified of which parts are defective and can be quickly determined when replacing parts, allowing for easy repair.

[Brief explanation of the drawing]

10 B) Fig. 1 is a perspective view of the overall appearance of the heating cooker of the present invention, Fig. 2 is a circuit diagram showing the overall configuration of the circuit of the present invention, and Fig. 3 is a temperature display segment of the temperature display means of the present invention. 4 is a flowchart showing the operation of the microcomputer in the control circuit of the present invention, FIG. 6 is a signal waveform diagram of each part of the present invention, and FIG. 6 is a diagram of the temperature display segment in each abnormal mode of the present invention. It is a figure showing a lighting state. 2...Heater, 3...Control circuit, 6
...Temperature sensor (thermistor), 6...
...Temperature display means, 7...Temperature setting means, 12
a...Relay contact, 12b...Relay coil, 71-82...Temperature display segment. Name of agent: Patent attorney Shigetaka Awano and 1 other person

Claims (1)

[Scope of Claims] It has a heating means used for cooking, a control circuit that controls energization of the heating means, and a temperature sensor that measures the temperature of the cooking container, and the control circuit measures the temperature of the cooking container. The temperature display means includes a temperature setting means for setting, a temperature display means for displaying the set temperature, and an opening/closing means for turning on/off energization to the heating means, and the temperature display means is composed of a plurality of display segments showing individual set temperatures. The control circuit detects whether or not there is an abnormality in the constituent parts or the temperature sensor, and determines one segment corresponding to one cause of the abnormality, and when an abnormality is detected, one of the plurality of display segments is selected according to the cause of the abnormality. A heating cooker that makes the display of a corresponding segment different from the display of other segments, and when the cause of the abnormality overlaps, makes the display of all the corresponding segments different from the display of other segments at the same time.