JPH0779752B2 - Control device for jar rice cooker - Google Patents

Description

TECHNICAL FIELD The present invention relates to a heater control device for a jar rice cooker.

2. Description of the Related Art A conventional configuration will be described with reference to FIG.

The AC power source 1 heats the body heater 2 and the bottom heater 3. When the relay 4 is energized, the bottom heater 3 is heated, and when the bidirectional thyristor 5 is energized, the body heater 2 and the bottom heater 3 are simultaneously heated. Then, the bidirectional thyristor 5 is driven by the bidirectional thyristor drive circuit 6, and the drive circuit 6
Is controlled by the microcomputer 7. When the rice is cooked or the heat retention switch 8 is input, if the temperature is low, the temperature is maintained and the drive circuit 6 is driven, and the bidirectional thyristor 5 is energized.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention Recently, however, in a jar rice cooker, it is desired not only to heat from the bottom heater 3 and the body heater 2 but also from more directions to cook more delicious rice, or to avoid two dew drops. There is a demand for heating the lid in order to increase the number of heaters to be controlled. Therefore, the number of heaters to be controlled is increased, and the number of bidirectional thyristors that control the heaters is also one as in the past. Instead, a plurality of devices have been energized alternately with a constant duty. Therefore, when a specific bidirectional thyristor is energized during mass production, there is a problem that it is necessary to wait until the bidirectional thyristor is energized in order to check the power capacity of the heater to be heated.

The present invention solves the above-mentioned problems, and an object of the present invention is to obtain a control device for a jar rice cooker in which it is easy to inspect the power of a hitter.

Means for Solving the Problems In order to achieve the above object, the present invention comprises a plurality of heaters,
A plurality of switching elements that control the energization of each of the heaters, drive circuits that respectively drive the switching elements, a heat retention switch, and the drive circuits are alternately energized at a constant duty from the start of heat retention, and the heat retention is maintained. The control means always starts energization from a certain specific drive circuit when the temperature is kept warm by the input from the start switch.

Effect The present invention has the above-described configuration, and when the heat retention is started by the input from the heat retention switch, the drive circuit of the switching element of the heater whose power capacity is to be inspected is driven, so that the waiting time for inspecting the power capacity of the heater is reduced. It can be greatly reduced.

Embodiment An embodiment of the present invention will be described below with reference to the accompanying drawings.

In FIG. 2, a bottom heater 11 is attached to the main body 9 so as to be in contact with the bottom of the inner pot 10, and a body heater 12 is attached to be in contact with the body of the inner pot 10. A lid heater 14 is attached to the bottom of the lid 13.

FIG. 1 is a circuit diagram of this embodiment. The AC heater 15 heats the bottom heater 11, the body heater 12, and the lid heater 14. The relay 16 energizes the bottom heater 11 and the bidirectional thyristor 17 energizes the bottom heater 11.
The energization of the body heater 12 and the energization of the lid heater 14 are controlled by the bidirectional thyristor 18. The drive circuit 19 drives the bidirectional thyristor 17, and the drive circuit 20 drives the bidirectional thyristor.
18 are respectively driven, and the microcomputer 21 controls the drive circuit 19 and the drive circuit 20. When there is an input from the heat retention switch 22, it becomes a heat retention state.

FIG. 3 is a flow chart of the movement of the microcomputer 21. t
Is the time being counted by the counter in the microcomputer, and T ₁ , T ₂ , and T ₃ are fixed times with the relationship of T ₁ <T ₂ <T ₃ .

Next, the operation of the above configuration will be described.

In mass production of this rice cooker, it is necessary to inspect the power capacity of the bottom heater 11 and the body heater 12 when the bidirectional thyristor 17 is energized.

Next, the operation of the microcomputer 21 will be described with reference to FIG. First, at the time of heat retention start other than input by the heat retention switch (when rice is cooked, etc.), the time t is naturally 0, so the time T becomes smaller than the fixed time T ₁ , so the drive circuit 20 is driven and the bidirectional thyristor 18 is driven. To be done. Then, when t becomes larger than T ₁ , the driving circuit 20 stops driving, and then t = T ₂
When (T ₂ > T ₁ ), the drive circuit 19 is driven and the bidirectional thyristor 17 is operated. When t becomes larger than T ₃ , t = 0, and this operation is repeated again at a constant cycle T ₃ .

The next time the warm start by the input of thermal insulation switch 22, since the start than at time t = a certain period of time T _2,
As can be seen from FIG. 3, the driving circuit 19 drives the bidirectional thyristor 17. And t is a fixed time
When I grow than T ₃ t = 0, and the rest is repeating the same operation as warm start other than the input of thermal insulation switch 22 described above with a constant period T _3.

In the case of this embodiment, as described above, the bottom heater 11 when the bidirectional thyristor 17 is energized during mass production,
Since it is necessary to inspect the power capacity of the body heater 12, the bidirectional thyristor 17 is immediately energized when the heat retention is started by the input of the heat retention switch 22, so that the power capacity can be inspected without waiting time. Is.

As described above, according to the present invention, when the temperature is kept warm by the input from the heat retention switch, the bidirectional thyristor that controls the heater whose power capacity is to be inspected immediately after the start of heat retention, such as during mass production, is driven. Since it operates, the power capacity can be inspected without waiting time during mass production, and an efficient rice cooker control circuit with high mass productivity can be realized.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a control device for a jar rice cooker according to an embodiment of the present invention, FIG. 2 is a sectional view showing an internal configuration of the jar rice cooker according to an embodiment of the present invention, and FIG. FIG. 4 is a flowchart showing the operation of the microcomputer of the control device of the jar rice cooker in one embodiment, and FIG. 4 is a circuit diagram of the control device of the conventional jar rice cooker. 11 …… Bottom heater, 12 …… Body heater, 14 …… Lid heater, 1
7,18 ... Bidirectional thyristor, 19,20 ... Bidirectional thyristor drive circuit, 21 ... Microcomputer (control means).

Claims (1)

[Claims] 1. A plurality of heaters, a plurality of switching elements for controlling energization of the heaters, drive circuits for driving the switching elements, a heat retention start switch, and a heat retention start for the drive circuits. A control device for a jar rice cooker, which comprises control means for alternately energizing at a constant duty from time to time, and always starting energization from a specific drive circuit when the temperature is kept warm by an input from a warming start switch.