JPS607486B2 - Cooking device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cooking device such as a heat-retaining rice cooker. This is for making settings.

In order to set the operating time of the heating circuit and the operating time of the notification circuit, which are completely separate operations, separate timer circuits are usually configured to accompany each operating circuit. Therefore, when two operating circuits are provided, two timer circuits are required, which has the disadvantage of increasing costs. Here, the temperature increasing circuit is used to control the temperature in order to control the temperature at a second set temperature that is higher than the normal first set temperature at the initial stage of energization when temperature control is performed by the temperature control circuit. This is a circuit for making the set temperature of the circuit higher than the first set temperature by a constant temperature. The present invention solves the above-mentioned conventional drawbacks, and embodiments of the present invention will be described below with reference to the accompanying drawings.

First, an outline of this embodiment will be explained with reference to FIG.
The thyristor i controls the temperature control circuit A which receives the signal from the temperature detection thermistor 3 to maintain the temperature of the controlled object at a constant temperature. A heating circuit B works to raise the temperature, a timer circuit C regulates the operating time of the overflow circuit B, and after a certain period of time set by the timer circuit C, a buzzer etc. is used to notify the completion of cooking. In response to signals from notification circuit D and temperature control circuit A,
and a prohibition circuit E for stopping one of the operations.

First, when cooking rice, the automatic switch 4 closes the b contact and energizes the rice cooking heater 5, and the temperature inside the cooking container (solid line F) rises as shown in Fig. When rice cooking is completed, the container temperature rises to about 12,000, and the automatic switch 4 closes the A contact side.From this time t, the temperature control circuit A is energized and starts operating. ~Temperature of temperature detection thermistor 3 (solid line G
) is higher than the control temperature, so thyristor 1 is turned off.

At this time, the prohibition circuit E receives a signal from the temperature control circuit A, prohibits the operation of the temperature increase circuit B, activates the timer circuit C and the notification circuit D, and starts the timer circuit C from time t. After a certain period of time has elapsed after the operation starts, the iron notification circuit D is activated to notify that cooking has been completed.

This buzzer sound will automatically stop after a certain period of time.
The user can also stop it at any time.

Temperature inside the container F! After the rice is cooked, the temperature gradually decreases and the temperature is maintained at a constant temperature by the temperature control circuit.

After this, ``If the power source is disconnected once due to the distance between the dining table and the power source, ``During that time, the temperature inside the thermal container will drop below the thermal insulation temperature.''

In order to reach the insulation temperature as quickly as possible, when the temperature of the insulation container whose temperature has decreased is lower than the insulation temperature, the next time the power is turned on again, if the power is turned on to the circuit when the temperature of the insulation container is lower than the insulation temperature. In response to a signal from control circuit A, prohibition circuit E operates until the thermistor temperature reaches the heat retention temperature. From the point when the thermistor temperature reaches the first set temperature T, the prohibition of operation of the salt booster circuit B and timer circuit C is released, and as shown in Figure 3, from this point (when the thermistor temperature reaches the first set temperature T), the timer The control temperature is set to the first set temperature T and the higher second set temperature T2 only for a certain period of time when the circuit C is working.
After a certain period of time has elapsed, the timer circuit C stops the operation of the temperature raising circuit B, and the controlled temperature of the temperature control circuit A is returned to the first set temperature T. By performing such a temperature raising operation, the initial startup of the heat insulating container can be made faster.

Next, a description will be given according to a specific electric circuit shown in FIG.

When rice cooking is finished and the rice cooking switch mother is switched to the a contact side, the temperature control circuit etc. are energized.

Since the temperature of thermistor 3 is high,
The side input becomes higher than the ten side input, and the output becomes L level, and since the gate power to the thyristor 1 is not supplied, the thyristor tortoise is turned off.

At this time, the output of the inverter 7 becomes H level and supplies the base current to the transistor 8 through the resistor 9, so the transistor 8 becomes ○N, and therefore the transistor 0 also turns ON.
becomes.

Output 11 of the timer circuit is at H level, but since transistors 8 and 10 are ON, diode 2 is reverse biased.On the other hand, since the output of inverter 3 is at L level, the current flows through transistors 8 and 8. The current is
The signal does not enter the reset terminal of the timer circuit C, but flows through the diode box 4 to the output terminal of the inverter 13.

From the time the timer circuit Q is energized, it oscillates at the oscillation frequency determined by the variable resistor 1f and the capacitor 81. This oscillation pulse is counted and after a certain period of time, the timer circuit C
The output li of is switched from H level to L level.

When the output thunderbolt reaches the 1st level, the multipipulator consisting of the inverter of the alarm circuit D starts oscillating and makes the second electric buzzer sound.

Due to the oscillation of the multipipulator ~ diode 22,
The capacitor 24 is charged through the resistor 23, the terminal voltage is increased, and after a certain period of time, the input level of the inverter 7 becomes H level, the output is inverted from H level to L level, and the output of inverter 3 becomes H level. do. When the output of inverter 3 becomes H level ~ inverter turtle 7, heavy 8? The oscillation of the multi-pipe layer composed of 19 and 28 stops. After that, Samis Yu 3,
The comparator 6 detects the output of the resistor bridge consisting of resistors 25 and 26, resistors 27 and 28, drives the thyristor 1, controls the electric power of the heat-retaining heater 2, and sets the first set temperature T,
to control the temperature.

Next, if the power is turned on when the thermistor temperature is lower than the heat retention temperature, the output of comparator 6 becomes H level, turning on the thyristor.

The output of the inverter 7 goes to the H level at the moment the power is turned on, turning on the transistors 8 and 18, but since the output of the comparator 6 is at the H level, the diode 2
9, the capacitor 24 is charged through the resistors 30 and 31, the input level of the inverter 7 becomes H level, the output becomes L level, and the output of the inverter 13 becomes H level. Therefore, the current flowing through the transistors 8 and 10 enters the reset terminal of the timer circuit C through the diode 32 and stops the operation of the timer circuit C. Also, the oscillation of the multipipulator is stopped. Thermistor 3
When the temperature rises and reaches the first set temperature T, the output of the comparator 6 becomes L level, and the diode 33
Since the base potential of the transistor flea is lowered through the transistor flea, it turns off, and at the same time, transistor
becomes. When transistors 8 and 10 are turned off, the IJ set current to timer circuit C disappears, and at the same time, current flows through diode 12 and resistor 281, and comparator 6
Increase the voltage of the input on the positive side. As a result, the set temperature of temperature control circuit A increases. From this point on, the timer circuit C operates, and after a certain period of time, the output switches from ~H level to L level, so that the diode 12 is reverse biased again and returns to the first set temperature T. As is clear from the following description, according to the present invention, the operating time of the temperature rising circuit and the operating time of the notification circuit can be set using one timer circuit, and the cost is reduced. It has great industrial value as it can prevent malfunctions.

[Brief explanation of the drawing]

Fig. 1 is a block circuit diagram of a cooking device showing an embodiment of the present invention, Fig. 2 is a temperature characteristic diagram of the cooking device, and Fig. 3 is a diagram showing the container when the power is turned on and off while keeping the cooking device warm. A temperature characteristic diagram of the thermistor, and FIG. 4 is an electric circuit diagram of the same cooker. 3...Thermistor, A...Temperature control circuit, B.
... Temperature rising circuit, C ... Timer circuit, D ... Notification circuit "B ... Prohibition circuit. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. A temperature control circuit that maintains the temperature of the controlled object at a constant level based on the signal from the temperature detection element, a temperature raising circuit that raises the controlled temperature of this temperature control circuit by a fixed temperature, and a driving time of this temperature raising circuit. A timer circuit for regulation, a notification circuit for giving notification after a certain period of time set by the timer circuit, and an output of the temperature control circuit to drive either the notification circuit, the temperature increase circuit, or the timer circuit. A cooker that is equipped with a prohibition circuit that stops the operation.