JPH026887Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to improvements in electronic rice cookers, rice cookers, etc., which control rice cooking and heat retention using a microcomputer.

BACKGROUND ART Rice cookers that use microcomputers (hereinafter referred to as "microcomputers") to cook rice, keep it warm, and keep it safe have been developed. Figures 1 and 2 are
These are diagrams showing the configuration of a microcomputer-controlled rice cooker according to the present invention developed and proposed by the present inventors. Figure 1 is a block diagram showing the system configuration of this rice cooker, and Figure 2 is a cross-sectional view of its main parts. It is a diagram. In FIGS. 1 and 2, reference numeral 1 denotes a lateral temperature sensor that detects the temperature on the side of the inner pot 21 of the rice cooker, and measures the temperature inside the inner pot of the rice cooker. 2 is a rice cooking temperature detection sensor disposed at the center of the inner bottom surface of the rice cooker, which measures the temperature near the bottom of the pan and detects the end of rice cooking. A safety temperature sensor 3 is attached to a microcomputer board 22 disposed on the outer bottom of the rice cooker with a gap in between, and is used to protect electronic components constituting the microcomputer from malfunction or damage due to abnormal temperatures. 4 is a power failure memory circuit whose operation will be explained in detail later with reference to FIG. 3, and is provided in the microcomputer board. 5 is an inner pot detection sensor placed on the side of the rice cooker, and when the inner pot is set, the lever 5a moves from the broken line position to the solid line position as shown in the figure, indicating whether the inner pot is set or not. This is to detect whether or not this is the case. A permanent magnet 5b, a reed switch 5c, etc. are used as the sensor. 6 is a rice cooking switch, 7 is an additional cooking switch, 8 is an abnormal temperature detection circuit attached to the microcomputer board, 9 is a microcomputer, 10 is a rice cooking display unit that indicates that a series of rice cooking processes are in operation, 11 is a This is a heat retention display section that indicates that the heat retention operation is in progress. 12 is a notification buzzer, and 13 is a heating circuit for the rice cooking section and the warming section.

Put rice in the inner pot and set it on the rice cooker main unit 20,
When a power switch (not shown) is turned on and the rice cooking switch 6 is turned on, the rice cooking display section 10 lights up, and a command is issued from the microcomputer 9 according to a program installed in the microcomputer 9, and rice cooking starts. Ru. At this time, each sensor monitors the cooking temperature, board temperature, etc. When the rice cooking is finished, the temperature of the inner pot rises, and this is detected by the center temperature sensor 2 for detecting the cooking temperature. As a result, the microcomputer 9 switches the heater of the heating circuit 13 to the heat keeping state, and lights up the heat keeping display section 11. If the temperature rises excessively due to a malfunction or the like, the safety temperature sensor 3 immediately detects this and turns off the power according to a command from the microcomputer.

According to such a microcomputer-controlled rice cooker, detailed control of rice cooking, heat retention, security, etc. is possible, and delicious rice can always be safely cooked without failure. Since these controls are performed using electronic circuits, the internal state of the circuits may change if there is a power outage.
The state of the rice cooking switch 6 immediately before the power outage becomes unclear, and even if the power is restored, rice cannot be cooked. In order to eliminate this drawback, a power failure memory circuit 4 (rice cooking memory circuit) is provided. This is to remember the state of the rice cooking switch 6 immediately before the power outage even when there is a power outage.

3A and 3B show an embodiment of the power failure memory circuit 4. FIG. In FIG. 3A, 4a is a comparator, to which a constant reference voltage is applied from a reference voltage source to the "+" terminal, and to the "-" terminal, a light is emitted which is turned on in response to a command from the microcomputer 9 to start cooking rice. The output of the rice cooking display section 10, which is composed of a diode or the like, is applied via a diode D. A capacitor C is further connected to the "-" terminal, and is charged by the output from the rice cooking display section 10. On the other hand, a transistor Tr is connected in parallel to the capacitor C, and is turned on and off by the output of the heat-retaining display section 11 made of a light emitting diode. Now, when rice cooking is started, the light emitting diode of the rice cooking display section 10 lights up, the capacitor C is charged via this, and the rice cooking state is memorized. Even if there is a power outage in this state, the charge in capacitor C is preserved, so when the power outage is restored and power supply starts again, microcomputer 9 will remove the charge in capacitor C using the output from comparator 4a. When the rice cooking switch 6 is detected and judged that the rice cooking is not finished, the rice cooking switch 6 is automatically turned on and electricity continues until the rice cooking is finished. When the rice cooking is finished, the inner pot temperature rises, so the rice cooking temperature detection sensor temperature sensor 2 detects this and informs the microcomputer 9. The microcomputer 9 immediately turns off the rice-cooking heater, switches to the heat-retaining heater, and performs control to shift to the heat-retaining state. At this time, the light emitting diode of the heat retention display section 11 lights up according to a command from the microcomputer 9, and the transistor Tr is turned on. By turning on this Tr, the charge in the capacitor C is discharged, and the capacitor C is reset.

FIG. 3B is another embodiment, similar to FIG. 3A, except that capacitor C is charged by microcomputer output 01 via diode D'. Normally, this kind of behavior is fine, but
If there is any kind of power outage while cooking rice (including unplugging the power outlet, tripping the breaker, or making a mistake), the machine will always remember the power outage (cooking memory), so even if you try to stop cooking, you will not be able to do so. In addition, there was a problem in that even if you tried to return the rice to a warm state, it would not be possible, and the rice would not return to its original state unless the rice was cooked anyway.

It is an object of the present invention to provide a rice cooker that solves the above-mentioned problems and allows a power failure memory circuit to be canceled as necessary to stop cooking rice or shift to a warm state.

The present invention has been made to achieve the above object, and its feature lies in the provision of a power failure memory circuit cancel switch SW.

Hereinafter, the present invention will be explained in detail with reference to Examples.

In addition, in FIGS. 4A and 4B, the same parts as in FIG. 3 are given the same symbols.

4A and 4B are diagrams respectively showing the configuration of the embodiment of the present invention, in which a power failure memory circuit cancel switch SW is provided in parallel with the power failure memory capacitor C of the power failure memory circuit 4 of FIGS. 3A and 3B. This power failure memory circuit cancel switch SW is configured to operate in conjunction with a power switch to discharge the charge stored in the power failure memory capacitor C.

Next, the operation of this embodiment will be explained.

As shown in FIGS. 4A and 4B, in the rice cooker of the present invention, a power failure memory circuit cancel switch SW is provided in parallel with the power failure memory capacitor C of the power failure memory circuit 4 in conjunction with the power switch. In this case, when the power switch is turned off, the power failure memory circuit cancel switch SW is turned on, and when the power switch is turned on, the power failure memory circuit cancel switch SW is turned off.

To cook rice, turn off the power switch and turn on the rice cooking switch 6, and the microcomputer 9 will start cooking the rice in response to a command. At this time, the power failure memory circuit cancel switch SW is turned off, so even if rice is in the middle of cooking, the power failure memory circuit 4 memorizes the state of the rice cooking switch 6 immediately before the power failure, so that the power failure state can be avoided. Once recovered, rice cooking will resume immediately.

Now, if you want to cancel the rice cooking operation automatically restarting for some reason when a power outage occurs, turn off the power switch once, and then turn on the power outage memory circuit cancel switch SW.
All that is required is to discharge the charge in the capacitor C in the power failure memory circuit 4.

If this is done, even if the power switch is turned on again, the rice cooking heater will not be energized and rice will not be cooked unless the rice cooking switch 6 is pressed.

As described above, according to the present invention, there is provided a microcomputer-controlled rice cooker having a power failure memory circuit that stores a rice cooking state immediately before a power failure and is equipped with a capacitor that is charged when a rice cooking switch is closed, A power failure circuit canceling means for discharging the electric charge stored in the power failure memory circuit is provided, and this power failure memory circuit canceling means is linked with the power switch, so that when the power failure condition is restored, the state automatically returns to the state of restarting rice cooking or keeping warm. By operating the power switch, the power switch can be turned on without automatically restarting rice cooking or warming.

Therefore, even if you turn on the power switch again,
The rice cooking heater is not energized unless the rice cooker switch is pressed, so if a power outage occurs, the rice cooker may be turned on or off depending on the power outage condition (long-term power outage, power outage with the outlet unplugged, power outage due to misuse, etc.). A person can consciously stop cooking rice.

[Brief explanation of the drawing]

1 and 2 are a block diagram and a sectional view of the main parts of the rice cooker showing the overall configuration of a microcomputer-controlled rice cooker according to the present invention, and FIGS. 3A and 3B are a diagram showing a power failure memory circuit according to the present invention. FIGS. 4A and 4B are diagrams illustrating the configuration of an embodiment of the power failure memory circuit cancel switch of the present invention. SW...Power failure memory circuit cancel switch, C
... Power failure memory capacitor, 4a... Comparator, 9... Microcomputer, 10... Rice cooking display section (light emitting diode), 11... Heat retention display section (light emitting diode).

Claims (1)

[Scope of utility model registration request] A microcomputer-controlled rice cooker having a power failure memory circuit that stores the state of rice cooking immediately before a power failure, which is equipped with a capacitor that is charged when a rice cooking switch is closed,
A rice cooker characterized in that a power failure memory circuit cancel means for discharging the electric charge charged in the capacitor is provided, and the power failure memory circuit cancel means is linked with a power switch to discharge the electric charge charged in the capacitor. .