JP2505937Y2 - Electric pot - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric pot.

[0002]

2. Description of the Related Art In a conventional electric pot, a heater is provided only on the bottom surface of a container. Then, in order to shorten the boiling time of the bottom heater, the power consumption of the bottom heater is increased.

[0003]

However, when the heater is provided on the bottom surface of the container as described above, there is a limit to the expansion of the heat generation area. Therefore, in order to increase the power consumption, the heat generation amount per unit area must be increased. Had to increase. For this reason,
There has been a problem that the durability of the heater is lowered and the noise when boiling water is increased. Also, since the steam holes in the inner lid are closed by the dance on the surface of the water when boiling water, the hot water in the container is naturally discharged, so there is a certain distance between the surface and the inner lid to prevent natural discharge. It was necessary to have a large margin. Therefore, the conventional electric pot has been upsized due to this margin. An object of the present invention is to solve such a problem, and it is possible to increase the amount of heat generation without lowering the durability of the heater and without increasing the noise at the time of boiling water. It is an object of the present invention to provide an electric pot that can reduce the margin.

[0004]

In order to achieve the above object, the present invention provides a first water heater on the bottom surface of a container integrally combined with a heat insulation heater and a second water heater on the side surface of the container. Then, the liquid in the container is heated by at least one of the water heaters. As an embodiment, it is possible to turn off the first boiling water heater and the heat retaining heater at a predetermined temperature near the boiling point, and then boil the liquid in the container with the second boiling water heater. Further, in this embodiment, a water level detecting means for detecting the water level of the liquid in the container is provided, and if the water level detecting means detects the minimum water level, the liquid in the container is replaced by the first water heating heater instead of the second water heating heater. It is also possible to bring to a boil.

[0005]

According to the above construction, the heater is divided into the first water heater on the bottom of the container and the second water heater on the side of the container.
Since the heat generation area of each water heater can be expanded, the heat generation amount per unit area is reduced. Since the warm water heater is integrally combined with the first water heater, even if the water level becomes low during heat retention, the heater will not be in an empty state.
Further, as in the embodiment, when the first water heater on the bottom surface is turned off before the start of the dance on the metal surface and the second water heater on the side surface is caused to boil, bubbling occurs in the peripheral portion and convection is improved. Therefore, the dance on the surface of the bath is reduced. Further, when the water level is low, if the first boiling water heater on the bottom surface is used to boil instead of the second boiling water heater, the second color boiling water heater on the side surface can prevent the occurrence of temper color due to empty heating.

[0006]

An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a bottom portion of an electric pot according to the present invention, 1 is an inner container, 2 is an outer shell, and 3 is a bottom body. Inner container 1
An annular first kettle heater 4 is attached to the outer surface of the bottom by a heater pressing plate 5, and a heat shield plate 6 is attached below the first kettle heater 4. The first boiling water heater 4 is a heat retention heater 12 (see FIG. 2).
(See)). Further, a rubber connecting tube 8 is attached to the outflow port 7 opening at the bottom corner of the inner container 1, and a pumping pipe 9 is attached through the connecting tube 8. Further, a thermistor 10 is attached to the center of the bottom of the inner container 1. On the bottom side surface of the inner container 1,
The second water heater 11 is wound around.

FIG. 2 shows the electric circuit of this electric pot.
The AC electric power source 13 is connected to the first water heating heater 4 via the first relay contact 14a, is connected to the heat retention heater 12 via the triac 15, and is connected to the second water heating heater 11 via the second relay contact 16a. It is connected. The gate terminal of the triac 15 is connected to one output terminal of the light receiving element of the photocoupler 17, and the other output terminal of the light receiving element is connected to the T ₂ terminal side of the triac 15. Transformer AC rectifier circuit 18 from the AC power supply circuit
The microcomputer 19 is connected to the DC power source obtained via the resistor 20, and the thermistor 10 connected in series with the resistor 20 is connected to the resistor 20 and the thermistor 10.
The divided voltage between the two is input to the input port of the microcomputer 19.

A first transistor 21 connected in series with the first relay coil 14b and a second transistor 22 connected in series with the second relay coil 16b are connected to the DC power supply. First and second
When excited, the relay coils 14b and 16b close the first and second relay contacts 14a and 16a, respectively. The bases of the first and second transistors 21 and 22 are connected to the output ports A and B of the microcomputer 19, respectively. Reference numerals 23 and 24 denote Zener diodes for protecting the first and second transistors 21 and 22. Further, this DC power source is connected to the anode of the light emitting element of the photocoupler 17, and the cathode of the light emitting element is connected to the output port C of the microcomputer 19.

Based on the water temperature detection signal detected by the thermistor 10, the selection signal from the power changeover switch 25, and the ON signal from the reboil switch 26, the microcomputer 19 follows the first program according to a built-in program.
The hot water heater 4, the warming heater 12 and the second hot water heater 11 are controlled to execute various modes as shown in FIG. The water amount determination mode is a mode for determining the amount of water in the inner container 1, and the high power water heating mode is the first water heating heater 4 and the second water heating heater 11.
Is a mode for boiling water with high power by the warming heater 12, the standard boiling mode is a mode for boiling water by the first boiling heater 4 and the warming heater 12, and the warming mode is a mode for keeping warm water by the warming heater 12. is there.

In the electric pot having the above structure,
When the water temperature is low when the power is turned on, it goes into the water quantity determination mode,
When the temperature is high, it becomes the heat retention mode. In the water amount determination mode, the microcomputer 19 keeps the output port A,
Output L (low) signal from C and H from output port B
Output a (high) signal. As a result, the first transistor 21 is turned on, a current flows through the first relay coil 14b, the first relay coil 14b is excited, and the first relay contact 14a is closed. As a result, the current is supplied to the first water heating heater 4. Flowing. At the same time, the photo coupler 17 is turned on and the triac 17 is turned on. As a result, a current flows through the heat retention heater 12.

Then, the microcomputer 19 stores the A / D value of the detection signal from the thermistor 10 as T ₀ , 10 seconds after the energization of the first boiling water heater 4 and the warming heater 12 is started, and If the A / D value increases by 17H (23 ° C.) from T ₀ during the water amount determination mode, it is determined that the water is not heated, and the output from the output ports A and C is stopped.
Instead of detecting the increase amount of the A / D value in this way, it is also possible to determine that the A / D value is COH (109, 6 ° C.) after the start of energization, and it is determined that the heating is not performed.

When the water amount determination mode is completed, the high power kettle mode or the standard kettle mode selected by the power changeover switch 25 is entered. In the high power boiling mode, the microcomputer 19 outputs a signal of L from all the output ports A, B and C. As a result, the first and second transistors 21 and 22 are turned on and both the first and second relay coils 14b and 16b are excited,
As a result of the closing of both the first and second relay contacts 14a and 16a, current flows through the first and second water heaters 4 and 11. Also, turn on the photo coupler 17 and turn on the triac 1.
As a result of 5 being turned on, a current also flows through the heat retention heater 12. Therefore, the first and second boiling water heaters 4 and 11 and the heat retention heater 12 perform boiling water with a high power of 1200 W.

When the temperature of the water in the inner container 1 gradually rises and the thermistor 10 detects 89.8 ° C. as shown in FIG. 4, the microcomputer 19 outputs a signal of H from the output ports A and C. . As a result, the first transistor 21 is turned off, the first relay coil 14b is demagnetized, and the first
As a result of the relay contact 14a being opened, the current to the first water heating heater 4 is cut off. At the same time, the photocoupler 17 is turned off and the triac 15 is turned off, so that the current to the heat retention heater 11 is cut off. Therefore, thereafter, the heating is continued to the boiling point (100 ° C.) only by the second water heating heater 11 on the side surface.

In the heating by the second boiling water heater 11 on this side surface, bubbles rise not from the entire bottom surface of the inner container 1 but from the inner peripheral portion thereof, and convection is promoted. Therefore, since the steam holes of the inner lid (not shown) are not blocked by the boiling water surface, the margin for preventing spontaneous discharge between the water surface and the inner lid is reduced, and the maximum water surface level is not shown. Allows access to the inner lid, making the container compact.

In the standard water heating mode, the microcomputer 19 outputs the L signal from the output ports A and C and the H signal from the output port B. As a result, the first transistor 21 is turned on, a current flows through the first relay coil 14b, the first relay coil 14b is excited, and the first relay contact 14a is closed. As a result, the current is supplied to the first water heating heater 4. Flowing. At the same time, the photo coupler 17
Is turned on and the triac 17 is turned on, and as a result, a current flows through the heat retention heater 12. Therefore, the water in the inner container 1 is heated by the first boiling water heater 4 and the heat retention heater 12, and the boiling water is started with the standard power of 750W.

The high power kettle mode and the standard kettle mode can be switched to each other by the power changeover switch 25, and in any of these modes, boiling detection is performed when the water temperature reaches a predetermined temperature (94 ° C.) near the boiling point. Transition to mode. When cold water is added and the water temperature drops, the high-power kettle mode or the standard kettle mode is selected. When the thermistor 10 detects a boiling point (100 ° C.) in the boiling detection mode, the microcomputer 19 causes the output port A,
The H signal is output from all of B and C. As a result, the electric current to the first and second boiling water heaters 4 and 11 and the heat retention heater 12 is cut off, and the boiling water is completed. After a few minutes, the microcomputer 19 outputs the L signal from the output ports A and C for a predetermined time, and simultaneously outputs the H signal from the output port B. As a result, a current flows through the first water heating heater 4 and the heat retaining heater 12, and so-called calcination is performed.

After skipping, the microcomputer 19 outputs the L signal from the output port C only. This causes the transition to the heat retention mode. If the reboil switch 26 is turned on in the heat retention mode, the mode transitions to the boiling detection mode,
If cold water is added, the mode changes to the water amount determination mode.

In the standard boiling water mode of the above embodiment, the first boiling water heater 4 and the warming heater 12 are used to heat to the boiling point. However, in order to prevent the dance on the molten metal surface, it is the same as in the high power mode. You may control to. That is, when the thermistor 10 detects 89.8 ° C., the power supply to the first water heating heater 4 and the heat retaining heater 12 is cut off, and thereafter, only the second water heating heater 11 on the side surface is used for water heating. When the inner container 1 has a small amount of water and is heated by the second water heater 11 on the side surface, a so-called temper color is generated on the inner surface of the inner container. Therefore, a water level sensor is provided at an appropriate location of the inner container, and if this sensor detects the lowest level, the second water heater 12 is switched to the first water heater 4, and the first water heater is switched to the first water heater.
You may make it boil by the water heater 4.

[0019]

As is apparent from the above description, according to the present invention, the bottom surface is provided with the first water heating heater integrally combined with the heat retention heater, and the side surface is provided with the second water heating heater. Is large, the amount of heat generated per unit area is reduced, the durability of the heater is improved, and the noise during boiling is reduced. Also, the first water heater or the second
It is possible to select whether to use a water heater or a heater, and to select the electric power according to the power consumption situation of the household so that the breaker does not fall. Further, since the first boiling water heater which is integrally combined with the heat retention heater is provided on the bottom surface of the container, even if the water level becomes low at the time of heat retention, the water heating is prevented. In particular, according to the invention as claimed in claim 2, the first water heater and the heat retaining heater on the bottom surface are turned off at around 90 ° C. where the water surface begins to dance, and only the second water heater on the side surface is used for boiling, so that the hot water surface dance Is reduced. As a result, the phenomenon that the steam holes in the inner lid are closed due to the dance on the surface of the molten metal and the water spontaneously discharges due to the vapor pressure is unlikely to occur, so that the molten metal surface can be brought close to the inner lid, Can be made compact. further,
According to the invention of claim 3, when the water level is low, the state of the second side heater for heating water by the second heating heater disappears.
The occurrence of temper color is prevented.

[Brief description of drawings]

FIG. 1 is a bottom sectional view of an electric pot according to the present invention.

FIG. 2 is an electric circuit diagram of the electric pot of FIG.

3 is a transition diagram of a control mode of the electric pot of FIG.

FIG. 4 is a diagram showing temporal changes in power consumption and water temperature in the high-power kettle mode of the electric pot of FIG.

[Explanation of symbols]

1 ... Inner container, 4 ... 1st water heater, 11 ... 2nd water heater.

Claims (3)

(57) [Scope of utility model registration request] 1. A first water heater provided integrally with a heat-retaining heater is provided on the bottom surface of the container, and a second water heater is provided on the side surface of the container, so that at least one of the water heaters removes the liquid in the container. An electric kettle characterized by being heated. 2. The liquid in the container is boiled by the second water heater after the first water heater and the heat retaining heater are turned off at a predetermined temperature near the boiling point. Electric pot. 3. If a water level detecting means for detecting the water level of the liquid in the container is provided and the water level detecting means detects the minimum water level,
3. The electric kettle according to claim 2, wherein the liquid in the container is boiled by the first water heater instead of the second water heater.