JP2003325354A - Electric pot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric pot capable of performing heat-retention at a hot water temperature as high as possible while avoiding re-boiling in the reconnection of a power supply cord after disconnection. <P>SOLUTION: This electric pot has a temperature sensor for detecting the temperature of a liquid contained in an inner container and a control part for executing water heating control and warming control for controlling the current-carrying to a heater based on the detected temperature by the temperature sensor. The control part checks the detected temperature by the temperature sensor in an initial processing after reset, and performs the heat-retention control, when the detected temperature is a prescribed temperature (98.5°C) close to a boiling temperature or higher, at a temperature obtained by subtracting a prescribed differential temperature (1.5°C) from the detected temperature. When the detected temperature is lower than the prescribed temperature, the control part checks the detected temperature in boiling after performing the water heating control, and performs the heat-retention control at a temperature obtained by subtracting a differential temperature (2.5°C) larger than the above differential temperature from the detected temperature in boiling. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a control section for executing boiling water control and heat retention control based on the temperature detected by a temperature sensor, and electric power is supplied through a power cord having a connecting section which is easily detached from the pot body. Regarding the electric kettles. More specifically, the present invention relates to improvement of control executed by the control unit in the initial processing after energization when the power cord is once disconnected and then reconnected.

[0002]

2. Description of the Related Art Generally, an electric pot is connected to a magnetic plug (connecting portion) of a power cord at a side portion near a bottom portion of a pot body having an inner container and a heater. This magnet plug has a structure in which a permanent magnet is arranged between a pair of conductive members (contacts). The permanent magnet is attracted to the magnetic body provided in the plug receiving portion of the pot body, so that the electric connection between the power cord and the pot body is formed.

Therefore, when the power cord is pulled, the magnet plug is easily removed from the pot body. This is a safety structure that prevents the electric pot from falling due to the power cord being immediately detached from the electric pot, for example, when a person hooks the power cord. .

Further, since the electric pot has a simple function of boiling the liquid (usually water) contained in the inner container to keep it warm, the water heater can be energized simply by connecting the power cord to the commercial power source. When the liquid is boiled (when the water is boiled), control is performed such that the electric power for the boiling water heater is turned off and the heat retention heater is turned on.

Recent electric pots are equipped with a temperature sensor for detecting the temperature of the liquid contained in the inner container, and a microcomputer (control section) for controlling the energization of the water heater and the warming heater according to the detected temperature. There are many. Also in this case, as described above, it is general that the boiling water control is started only by connecting the power cord to the commercial power supply, and when the boiling water boiled, the heat retention control is performed. For example, when the rate of change of the detected temperature becomes smaller than the threshold value, it is determined that the hot water has boiled, and the heat retention control is performed. In the heat retention control, the energization of the heat retention heater is usually controlled so as to maintain the hot water temperature of about 98 ° C.

Further, as the heat retention temperature, for example, 90 ° C. or 60
Some models have a low temperature insulation mode that can be set to ℃,
Even in that case, in most of the models, 98 ° C is set as the heat retention temperature in the default state immediately after energization. In the high temperature heat retention mode where the heat retention temperature is 98 ° C, in consideration of changes in atmospheric pressure (falling boiling point) and variations in temperature sensors, etc. In many cases, the energization of the heat retention heater is controlled so that the temperature of the hot water is about ℃.

[0007]

In the high temperature insulation mode of an electric pot equipped with a temperature sensor and a microcomputer, it is desirable to keep the temperature of the hot water as close to 98 ° C. as possible while avoiding unnecessary boiling. For that purpose, it is necessary to set the heat retention temperature (the lower limit value and the upper limit value of the detected temperature at which the heat retention heater is turned on and off) as high as possible.

However, if the heat retention temperature in the high temperature heat retention mode is raised, boiling may occur during heat retention due to changes in atmospheric pressure (falling boiling point) and variations in temperature sensors due to places of use (altitude) and weather conditions. Will be more likely.

Further, as described above, when the power cord is disconnected from the pot body and the power cord is connected after the power failure holding time elapses and the microcomputer (control unit) is reset, the hot water temperature is sufficiently high. Even if (not cold), the microcomputer starts from the kettle mode. As a result, unnecessary boiling is performed.

The present invention has been made in view of the above problems, and in the case where the power cord is once disconnected and then reconnected, the temperature is kept as high as possible while avoiding reboil. It is intended to provide an electric pot in which

[0011]

A first structure of an electric pot according to the present invention is a pot body having an inner container and a heater, and a lid attached to the upper part of the pot body so as to open and close the upper opening of the inner container. A body, a temperature sensor for detecting the temperature of the liquid contained in the inner container, and a control unit for performing heating control and heat retention control for controlling energization of the heater based on the temperature detected by the temperature sensor, An electric pot in which electric power is supplied to an electric circuit including a heater and a control unit via a power cord having a connection portion that is easily detached from the pot main body, wherein the control unit is a temperature sensor in an initial process after energization. Check the detected temperature,

When the detected temperature is equal to or higher than the first temperature (eg, 98.5 ° C.) close to the boiling temperature, the heat retention control is performed at the second temperature (eg, 97 ° C.) lower than the first temperature by a certain temperature. The detected temperature is the first temperature (for example, 9
When the temperature is lower than 8.5 ° C., the heat retention control is performed after the boiling water control is performed.

According to this structure, when the power cord is once disconnected and then reconnected, and when the hot water temperature is sufficiently high (not cooled), the control unit starts from the hot water heating mode. Don't go into the heat retention mode immediately. Therefore, unnecessary boiling is not performed and an energy saving effect is obtained.

In a preferred embodiment, the control unit checks the temperature when the temperature sensor is boiling when performing the boiling water control, and determines a predetermined temperature difference (for example, 2.5 ° C.) from the temperature when boiling. Insulation control is performed at the reduced temperature.
As a result, with the detected temperature immediately before as a reference, unnecessary boiling is unlikely to occur, and the heat retention temperature is set to a temperature as high as possible (a temperature close to 98 ° C.).

The second configuration of the electric pot according to the present invention is
A pot body having an inner container and a heater, a lid attached to the upper part of the pot body so as to open and close the upper opening of the inner container, and a temperature sensor for detecting the temperature of the liquid contained in the inner container, A heater for controlling the energization of the heater on the basis of the temperature detected by the temperature sensor, and a controller for executing the heat retention control, and the heater and the controller are provided via a power cord having a connecting portion easily detached from the pot body. An electric pot in which electric power is supplied to the electric circuit, wherein the control unit checks the detection temperature of the temperature sensor in an initial process after energization, and the detection temperature is a predetermined temperature close to the boiling temperature (for example, 98.5). C.) or more, a predetermined temperature difference from the detected temperature (for example, 1.5
The temperature retention control is performed at a temperature obtained by subtracting (.degree. C.), and when the detected temperature is lower than the predetermined temperature, the temperature retention control is performed after performing the boiling water control.

According to this structure, when the power cord is once disconnected and then reconnected, and when the hot water temperature is sufficiently high (not cooled), the control unit starts from the hot water heating mode. Don't go into the heat retention mode immediately. Therefore, unnecessary boiling is not performed and an energy saving effect is obtained. Also, based on the temperature detected immediately before,
The heat retention temperature is set to a temperature as high as possible (a temperature close to 98 ° C.) without causing unnecessary boiling.

In a preferred embodiment, the control unit checks the temperature detected when the temperature sensor is boiling when the water boiling control is performed, and the temperature difference from the temperature detected when boiling is larger than the above difference temperature (for example, 2. Temperature control is performed at a temperature less than (5 ° C). As a result, with the detected temperature immediately before as a reference, unnecessary boiling is unlikely to occur, and the heat retention temperature is set to a temperature as high as possible (a temperature close to 98 ° C.).

A third configuration of the electric pot according to the present invention is
A pot body having an inner container and a heater, a lid attached to the upper part of the pot body so as to open and close the upper opening of the inner container, and a temperature sensor for detecting the temperature of the liquid contained in the inner container, A heater for controlling the energization of the heater on the basis of the temperature detected by the temperature sensor, and a controller for executing the heat retention control, and the heater and the controller are provided via a power cord having a connecting portion easily detached from the pot body. In an electric pot for supplying electric power to an electric circuit, a control unit checks a temperature detected by a temperature sensor in an initial process after energization, and the detected temperature is equal to or higher than a first temperature (for example, 99.5). Temperature), the temperature control is performed at a temperature obtained by subtracting the first difference temperature (eg, 2 ° C.) from the detected temperature, and the detected temperature is equal to the first temperature (eg, 99.5 ° C.). Lower second temperature than Re (e.g. 9
If the temperature is between 8.5 ° C), the temperature is kept at a temperature obtained by subtracting a second differential temperature (eg 1.5 ° C) smaller than the first differential temperature (eg 2 ° C) from the detected temperature. The control is performed so that the detected temperature is the second temperature (for example, 98.5 ° C.).
When the temperature is lower, the heat retention control is performed after the boiling water control is performed.

According to such a configuration, when the power cord is once disconnected and then reconnected, and when the hot water temperature is sufficiently high (not cooled), the control unit starts from the hot water mode. Don't go into the heat retention mode immediately. Therefore, unnecessary boiling is not performed and an energy saving effect is obtained. Also, based on the temperature detected immediately before,
The heat retention temperature is set to a temperature as high as possible (a temperature close to 98 ° C.) without causing unnecessary boiling. Furthermore,
Compared with the second configuration, the heat retention temperature is set in two steps according to the detected temperature, so that more detailed heat retention control can be performed.

In a preferred embodiment, the control unit checks the temperature detected when the temperature sensor is boiling when performing the boiling water control, and determines the first temperature from the temperature detected when boiling.
Insulation control is performed at a temperature obtained by subtracting the third difference temperature (for example, 2.5 ° C.) that is greater than the difference temperature of As a result, with the detected temperature immediately before as a reference, unnecessary boiling is unlikely to occur, and the heat retention temperature is set to a temperature as high as possible (a temperature close to 98 ° C.).

The fourth constitution of the electric pot according to the present invention is
A pot body having an inner container and a heater, a lid attached to the upper part of the pot body so as to open and close the upper opening of the inner container, and a temperature sensor for detecting the temperature of the liquid contained in the inner container, A heater for controlling the energization of the heater on the basis of the temperature detected by the temperature sensor, and a controller for executing the heat retention control, and the heater and the controller are provided via a power cord having a connecting portion easily detached from the pot body. An electric pot for supplying electric power to an electric circuit, wherein the control unit has a heat retention temperature of about 90 ° C. or lower (for example, 60 ° C.).
When the low temperature heat retention mode for performing heat retention control at (° C) is selected, the temperature detected by the temperature sensor is checked, and the detected temperature is lower than the heat retention temperature (for example, 60 ° C) by a predetermined temperature (for example, 58 ° C). In the above case, only the warming heater of the boiling water heater and the warming heater constituting the heater is energized, and when the detected temperature is lower than the predetermined temperature (for example, 58 ° C.), both the boiling water heater and the warming heater are turned on. It is characterized by energizing.

According to this structure, the heater for boiling water is not energized unnecessarily, which is preferable from the viewpoint of energy saving.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of an electric pot according to an embodiment of the present invention. This electric pot comprises a pot body 11 mainly covered with a resin molded product and a lid body 12 attached to the upper part of the pot body. The pot body 11 has an inner container 13 for containing a liquid (usually water or hot water). And a heater 14 attached to the bottom thereof. The lid 12 has a lid member 15 made of a resin molded product and an inner lid 16 made of sheet metal fixed to the lower side of the lid member 15, and is supported by a support shaft 17 at the rear end of the upper end of the pot body 11 (right side in FIG. 1). ) Is supported by.

In the inner container 13, an inner cylinder 13a and an outer cylinder 13b made of stainless steel are provided at the outer portion 1 of the bottom and upper openings.
The inner cylinder 13a and the outer cylinder 1 have a double structure joined by 3c.
A vacuum layer is formed between 3b and 3b. With a vacuum double structure similar to a so-called thermos, a predetermined hot water temperature can be maintained for a certain period of time without heating by a heater.

On the outside of the bottom surface of the inner container 13, a heater 14 composed of a water heater and a heat retaining heater is attached so as to be in close contact with each other. There is a space in the central portion of the disk-shaped heater 14, and a temperature sensor 19 for detecting the temperature of the liquid contained in the inner container 13 is attached here.
That is, the temperature sensor 19 is in close contact with the central portion outside the bottom surface of the inner container 13 and detects the temperature of the liquid via the bottom surface of the inner container 13. For example, the temperature sensor 19 is configured using a thermistor whose resistance value changes according to temperature, and in this case, the detected temperature can be obtained from the output voltage of the resistance voltage dividing circuit including the temperature sensor 19.

An opening 21 for hot water supply (discharging) is provided on the bottom surface of the inner container 13, and the opening 21 is communicated with the input side of the electric pump 22 by an input conduit 22a. The output-side pipe line 22b of the electric pump 22 is a discharge pipe 23 that extends substantially vertically from the bottom to the top of the electric pot.
It is connected to the base end side of. The tip end side of the discharge pipe 23 reaches a discharge port 25 through a valve mechanism 24 for preventing liquid leakage when the electric pot falls. The discharge pipe 23 is made of a transparent glass pipe, and the water surface inside thereof can be seen through a transparent window provided on the front surface 11a of the pot body 11. Thereby, the water level in the inner container 13, that is, the amount of remaining hot water can be known.

As can be seen from FIG. 1, the upper opening of the inner container 13 is narrowed so that the area in plan view is narrower than that of the tubular portion, which makes it difficult for the contained liquid to cool. A rubber packing 16a is attached to the outer peripheral portion of the inner lid 16 of the stopper. With the lid 12 closed, the rubber packing 16a comes into close contact with the upper edge of the inner container 13 (the inner cylinder 13a) to seal the upper opening of the inner container 13.

Further, a steam discharge path (arrow line) 27 extending from the steam hole formed in the inner lid 16 to the exhaust port 26 formed in the rear portion of the upper surface of the lid member 15 is provided. A valve mechanism (valve body) 28 for preventing the liquid leakage is provided. Further, a pressing-down operation portion 29, a spring 31, a bellows 32 are provided at the central portion of the lid body 12 (lid member 15).
Is provided with an air pump. This allows
The electric pot of the present embodiment is capable of manual hot water supply (air pump hot water supply) by pushing down the push-down operation unit 29, in addition to electric hot water supply by the electric pump 22. A safety lever for switching the push-down operation unit 29 between a locked state (a push-down prohibited state) and an unlocked state (a push-down possible state) is provided beside the push-down operation unit 29 in a plan view (not shown).

An operation panel 33 is provided on the front upper surface of the pot body 11. As shown in FIG. 2, the operation panel 33 includes a display unit 41 and a plurality of push buttons 42 to 46.
Is provided. As will be described later in detail, the user of the electric pot can know the temperature of the liquid (hot water) in the inner container 13, the time until boiling, and the like by the display on the display unit 41 of the operation panel 33. Also, push buttons 42-4
6 can be used to instruct hot water supply, set a heat retention temperature, and the like. The display unit 41 includes LEDs 41a and 41b that selectively indicate a boiling or heat retaining state and a liquid crystal display 41c including a 7-segment numerical display. Hot water lock release button 4
An LED 43a that is turned on in the unlocked state is provided on top of the LED 3.

The operation panel 33 is provided inside the operation panel 33.
Liquid crystal display 41c and LED 41 constituting the display unit 41 of
a, 41b, 43a, a switch group corresponding to the push buttons 42 to 46, a first printed circuit board (hereinafter referred to as a microcomputer board) 3 on which a control microcomputer and the like are mounted.
4 is installed. A second printed circuit board (hereinafter referred to as a power supply circuit board) 35 on which a drive circuit for the electric pump 22, a drive circuit for the heater 14, a power supply circuit, etc. are mounted is attached to the bottom of the electric pot.

FIG. 3 shows the microcomputer board 34 and the power supply board 3.
5 is a block diagram of a main part of an electric circuit including other electric components. The control unit 51 including a microcomputer includes push buttons 42 to 46 on the operation panel 33.
The signal of the switch group corresponding to is input through the switch input circuit 53. In addition, the control unit 51 displays, via the display drive circuit 54, the liquid crystal display 41c that constitutes the display unit 41 of the operation panel 33 and the LEDs 41a, 41b, 43a.
Controls turning on and off.

The detection signal of the above-mentioned temperature sensor 19 is A
It is input to the control unit 51 via the / D converter 56. However, when the control unit (microcomputer) 51 has an A / D converter built therein, the detection signal of the temperature sensor 19 is directly input to the control unit 51. The control unit 51 can know the temperature (detection temperature) of the liquid (hot water) in the inner container 13 by checking the detection signal of the temperature sensor 19 at an arbitrary timing. Further, a buzzer (piezoelectric buzzer) 57 is provided and is driven by the control unit 51 directly or via a drive circuit (not shown). Buzzer 57
Sounds when a notification sound such as the completion of boiling water or an operation sound of a push button is emitted.

The controller 51 also controls the power supply board 3 when hot water is supplied.
The drive control of the above-described electric pump 22 is performed via the pump drive circuit 58 mounted in FIG. Similarly, through the heater drive circuit 59 mounted on the power supply board 35, the energization of the boiling water heater 14a and the warming heater 14b constituting the heater 14 is individually controlled to control boiling water and keeping warm.

On the power supply board 35, a power supply circuit 6 for generating a DC voltage from a commercial AC voltage of AC 100 V and supplying it to the control unit 51, the pump drive circuit 58 and the heater drive circuit 59.
1 is implemented. An alternating current from AC 100 V flows through the heater 14, but a relay and a semiconductor switching element for controlling the on / off of the alternating current flow through the heater driving circuit 59.
And a drive current thereof is supplied from the power supply circuit 61. ON / OFF of the water heater 14a through which a large current flows is controlled by a relay, and ON / OFF of the heat retention heater 14b through which a small current flows is controlled by a semiconductor switching element. The electric pump 22 driven by a direct current is also controlled by the semiconductor switching element.

A power cable connected to an AC100V power outlet is connected to the pot body 11 by a magnetic plug. As is well known, the magnet plug has a structure in which a permanent magnet is arranged between a pair of conductive members (contacts) (not shown). Side (or rear) near the bottom of the pot body 11
The permanent magnet of the magnetic plug is attracted to the magnetic body of the plug receiving portion provided in the electric power cord and the pot body 11 (that is, the electric power circuit 61 of the electric power supply board 35) to form an electrical connection.

Therefore, when the power cord is pulled, the magnet plug can be easily removed from the pot body 11. This is a structure for safety, and for example, when a person hooks his / her foot on the power cord and the power cord is immediately detached from the electric pot, the risk of the electric pot falling down can be avoided. .

Further, a reset circuit 62 of the control section 51 is provided. When the power cord is connected and the electric pot is energized, the reset circuit 62 operates and a reset signal is given to the control unit 51. As a result, the control unit (microcomputer) 51 starts the operation from the initial processing (initial routine) according to the program stored in the ROM (read only memory).

In the electric pot of this embodiment, the RAM (random access memory) of the controller (microcomputer) 51 is not backed up by a battery.
Therefore, for example, when the magnet plug of the power cord is detached from the pot body 11 and the electric power supply to the electric pot is stopped, the data stored in the RAM (for example, the set temperature information) is lost (cleared). When the energization is started again, the normal operation starts according to the program stored in the ROM (for example, the heat retention temperature is set to the default value 98 ° C.).

Next, typical operations and operations of the electric pot of this embodiment will be described. First, in FIG. 1, the lid 1
2 is rotated backward about the support shaft 17 and opened rearward, and a required amount of water is put into the inner container 13. The lid 12 is closed, the magnet plug at the base end of the power cord connected to the electric pot is connected to the plug receiving portion of the pot body 11, and the plug (insert) at the tip is inserted into an AC100V outlet (outlet). Then, the power supply circuit 61 of the power supply board 35 is energized, and the current is supplied to the control unit 51 of the microcomputer board 34. At the same time, the reset circuit 62 operates to give a reset signal to the control unit 51. As a result, the control unit 51 starts the operation from the initial processing according to the program stored in the ROM.

The control unit 51 normally uses the water heater 14
When the energization of a is started, the operation panel 3 shown in FIG.
3 is displayed on the display unit 41, and push buttons 42 to 4
Pressing 6 will be recognized.

On the operation panel 33 of FIG. 2, 98 ° C. is set as the heat retention temperature in the default state, and the display unit 4
The upper triangular mark of the liquid crystal display 41c of No. 1 is displayed below 98. "Select" button 44, which is one of the push buttons
By pressing, the heat retention temperature can be switched to 90 ° C. Alternatively, "mahobin" can be selected. In the "mahobin", the energization of the heat retention heater is stopped, and the inner container 13 is kept warm by the double vacuum structure as described above. Each time the “select” button 44 is pressed, the triangle mark on the upper part of the liquid crystal display 41c moves to
8 ° C, 90 ° C or “Mahobin” is set.

The "boil" LED 41a is turned on while the water heater 14a is energized. The liquid crystal display 41c has
The time (minutes) until boiling is displayed. The character "after" is displayed in front of the 2-digit 7-segment display portion, and the character "minute" is displayed after the 2-digit 7-segment display portion.

When the rate of change of the detected temperature becomes smaller than the threshold value, the control unit 51 determines that the hot water has boiled, turns off the hot water heater 14a, and turns on and off the warming heater 14b to control the hot water in the inner container 13. The temperature of is maintained at a substantially heat retention temperature. At this time, the "boiling" LED 41a goes out,
The "warm" LED 41b lights up. Further, the hot water temperature detected by the temperature sensor 19 is displayed on the liquid crystal display 41c. As shown in FIG. 2, the word "temperature" is displayed in front of the 2-digit 7-segment display unit. When low temperature insulation (90 ° C) is selected, the hot water temperature is set to the set temperature (approximately 9
(0 ° C.), the water heater 14a is turned off, and the heat retention mode is switched to the heat retention mode by the on / off control of the heat retention heater 14b.

"Hot water supply" button 42 pressed when hot water is supplied
To ensure safety, the "unlock" button 43
After is pressed, it becomes effective only for a predetermined time (for example, 20 seconds). When the "unlock" button 43 is pressed, the LED 43a indicating unlocking lights up and goes out after a predetermined time. When the "hot water supply" button 42 is pressed while the LED 43a indicating unlocking is turned on, the electric pump 22 is driven and hot water is discharged from the discharge port 25. The electric pump 22 is driven only while the hot water supply button 42 is pressed,
When the finger is released from the hot water supply button 42, the electric pump 22 is stopped and the hot water supply is completed. The electric pot of the present embodiment is provided with a push-down operation unit 29 provided at the center of the lid 12.
By pressing down, manual hot water supply by the air pump is possible as described above.

When the "kitchen timer" button 45 is pressed on the operation panel 33 shown in FIG. 2, a preset time (for example, 3 minutes) is displayed as a two-digit number 7 on the liquid crystal display 41c.
It is displayed on the segment display and the timer countdown starts. When the timer expires (when the set time elapses), the buzzer 57 sounds to notify. Further, the "reboil" button 46 is pressed when it is desired to boil again during the heat retention.

In the above description, when the electric pot is turned on, the control unit 51 (microcomputer) is reset, and the default control is started from the initial process according to the program stored in the ROM. In the default control (that is, unless the setting of the heat retention temperature is changed), the water heater 1
4a is energized (boiling control). When the temperature of the hot water reaches approximately 98 ° C, the water heater 14a is turned off, and the temperature of the hot water in the inner container 13 is maintained at approximately 98 ° C by the on / off control of the warming heater 14b (heat retention control).

However, it is necessary to perform the boiling water control and the heat retention control so that the water temperature actually detected by the temperature sensor is exactly 98 ° C. because of factors such as variations in the temperature sensor and fluctuations in atmospheric pressure (boiling point). Have difficulty. For example,
At high altitudes, the atmospheric pressure is low, so the boiling point becomes low, and boiling of water begins at temperatures below 100 ° C. Therefore, if the actual heat retention temperature is set to 98 ° C., unnecessary boiling or steam is likely to occur during the heat retention control.

In order to avoid this, the lower limit value and the upper limit value of the hot water temperature actually detected by the temperature sensor (the temperature at which the heat retention heater 14b is turned on / off) are set to a low value (for example, 96 ° C. at the center value). There is a way to put it. However, there are times when hot water as hot as possible is needed.

Further, as described above, when the magnet plug of the power cord is detached from the pot body 11 to stop the energization of the electric pot and the energization of the electric pot is resumed after a while, the hot water temperature is changed. Even when is sufficiently high (not cooled), the control unit 51 starts the water heating control after the reset. As a result, unnecessary re-boiling is performed.

Therefore, in the electric pot of the present embodiment, the control unit 51 executes the process after reset as described below, so that the temperature is kept as high as possible while avoiding unnecessary re-boiling. I am trying to be seen.

FIG. 4 is a flow chart showing a first example of control after reset executed by the control unit 51. Control unit 5
After resetting, in step # 101 after resetting, initial processing such as RAM check and default display is executed, and then the temperature detected by the temperature sensor 19 is checked (step # 1).
02).

When the detected temperature is equal to or higher than the first temperature close to the boiling temperature (98.5 ° C. in the example of FIG. 4) (Yes in step # 103), the temperature is lower than the first temperature by a constant temperature in step # 104. The second temperature (97 ° C. in the example of FIG. 4) is set as the heat retention temperature, and the process proceeds to the heat retention control of step # 107. In such a case, for example, after the power cord is detached from the electric pot, the power supply to the electric pot may be restarted while the hot water temperature is sufficiently high (not cooled). In this case, the heat retention control is performed without unnecessary re-boiling by the above processing.

When the detected temperature is lower than the first temperature,
The normal water heating control is started (step # 105), and the water heating heater 14a is energized. When boiling water is detected as described above, the heat retention temperature is, for example, 97.5 ° C.
Is set (step # 106), and the process proceeds to the heat retention control of step # 107. In the heat retention control of step # 107,
The inner container 13 is controlled by the on / off control of the heat retention heater 14b.
The temperature of the hot water inside is maintained at a substantially warm temperature.

FIG. 5 is a flow chart showing a second example of control after reset executed by the control unit 51. The processing from step # 201 to step # 205 is shown in FIG.
Step # 101 to Step # 10 of the first example shown in FIG.
This is the same as the processing of 5. In step # 206, the control unit 51 checks the temperature detected by the temperature sensor 19 (boiling temperature). In the subsequent step # 207, a temperature obtained by subtracting a predetermined temperature difference (2.5 ° C. in the example of FIG. 5) from the detected temperature is set as the heat retention temperature, and the process proceeds to the heat retention control in step # 208. In the heat retention control of step # 208, the temperature of the hot water in the inner container 13 is maintained at a substantially heat retention temperature by the on / off control of the heat retention heater 14b.

In this example, since the heat retention temperature is set on the basis of the temperature actually detected by the temperature sensor 19 at the time of boiling, influences such as variations in the temperature sensor 19 and variations in atmospheric pressure are removed, and unnecessary re-production is performed. It is possible to keep the temperature as high as possible while avoiding boiling.

FIG. 6 is a flow chart showing a third example of control after reset executed by the control unit 51. The processing from step # 301 to step # 303 is shown in FIG.
Step # 101 to Step # 10 of the first example shown in FIG.
This is the same as the processing of 3. In step # 304 executed when the detected temperature is 98.5 ° C. or higher, the control unit 51 keeps the temperature obtained by subtracting a predetermined temperature difference (1.5 ° C. in the example of FIG. 6) from the detected temperature. The temperature is set and the process proceeds to the heat retention control of step # 308. Temperature sensor 19
Since the heat retention temperature is set on the basis of the temperature immediately before being actually detected, influences such as variations in the temperature sensor 19 and fluctuations in atmospheric pressure are removed, and the hot water temperature as high as possible is avoided while avoiding unnecessary re-boiling. You can keep it warm.

Regarding the processing from step # 305 to step # 308, step # 20 of the second example shown in FIG.
This is the same as the processing from step 5 to step # 208. However,
The processes from step # 305 to step # 308 are the same as step # 105 to step # 107 of the first example shown in FIG.
It is also possible to replace with the processing of.

FIG. 7 is a flowchart showing a fourth example of the control after the reset executed by the control unit 51. After executing the processes of step # 401 and step # 402 as in the control example described above, in this control example, the detected temperature is determined in two stages and a more appropriate heat retention temperature is set.

First, in step # 403, it is checked whether or not the detected temperature is equal to or higher than the first temperature (99.5 ° C. in the example of FIG. 7) close to the boiling temperature. When the temperature is equal to or higher than the first temperature, the detected temperature is changed to the first difference temperature (2
(° C) is set as the heat retention temperature (step #
404), and proceeds to the heat retention control of step # 410.

When the detected temperature is lower than the first temperature,
In the following step # 405, it is checked whether the temperature is equal to or higher than the second temperature (98.5 ° C. in the example of FIG. 7) lower than the first temperature. If it is equal to or higher than the second temperature, that is, if the detected temperature is between the second temperature (98.5 ° C.) and the first temperature (99.5 ° C.), the first difference from the detected temperature. A temperature obtained by subtracting the second difference temperature (1.5 ° C. in the example of FIG. 7) smaller than the temperature is set as the heat retention temperature (step # 406),
The process proceeds to the heat retention control in step # 410.

In this control example, when the power supply to the electric pot is resumed while the hot water temperature is sufficiently high (not cooled) after the power cord is disconnected from the electric pot, the detected temperature is adjusted according to the detected temperature. The heat retention control is set in two steps to shift to the heat retention control. Therefore, compared to the control example described above,
It is possible to avoid unnecessary re-boiling while finely setting a high heat retention temperature.

Regarding the processing from step # 407 to step # 410, step # 20 of the second example shown in FIG.
This is the same as the processing from step 5 to step # 208. However,
The processes from step # 407 to step # 410 are performed in steps # 105 to # 107 in the first example shown in FIG.
It is also possible to replace with the processing of.

FIG. 8 is a flow chart showing a fifth example of control after reset executed by the control unit 51. Unlike the control example described above, this flowchart is different from the control example described above, in which the low-temperature heat retention is set and the water heater 14a and the heat retention heater 1 are used.
4b regarding control. That is, the control unit 51
It is assumed that the low temperature heat retention (90 ° C.) is selected from the operation panel 33 shown in FIG. In addition, depending on the model of the electric pot, there is a model in which a heat retention setting of 60 ° C. is possible as a low temperature insulation, and this control example can be applied to such a model.

After executing the above-mentioned initial process in step # 501, the control section 51 checks whether or not the low temperature keeping is selected (step # 502). If low temperature insulation is selected, continue to step # 503.
The temperature detected by the temperature sensor 19 is checked with.

When the detected temperature is equal to or higher than the heat retention upper limit temperature (Yes in step # 504), both the water heater 14a and the heat retention heater 14b are turned off (step # 50).
5). The upper limit temperature of the heat retention is determined by the heat retention heater 1
4b means the temperature to turn off, for example the heat retention temperature 90 ℃
In this case, 90.5 ° C. is set, and in the case of a heat retention temperature of 60 ° C., 60.5 ° C. is set.

If the detected temperature is lower than the heat retention upper limit temperature (No in step # 504), in the next step # 506, the detected temperature is lower than the heat retention temperature by a predetermined temperature (see FIG. 8).
In the example of (1), it is checked whether or not the heat retention temperature is −2 ° C. or higher.
For example, when the heat retention temperature is 90 ° C., it is checked whether it is 88 ° C. or higher, and when the heat retention temperature is 60 ° C., it is checked whether it is 58 ° C. or higher.

If the detected temperature is equal to or higher than the predetermined temperature (eg, 88 ° C. or 58 ° C.) lower than the heat retention temperature by a constant temperature, only the heat retention heater 14b is turned on and the water heater 14a is turned off in step # 507. . A predetermined temperature (for example, 88
C. or 58.degree. C.), both the water heater 14a and the heat retention heater 14b are turned on in step # 508. By such heater control, the electric water heater 14a is not unnecessarily energized, and excellent heat retention control is performed. It is also preferable from the viewpoint of energy saving.

Although the embodiment of the present invention has been described above with reference to a plurality of control examples, the present invention is not limited to the above-described embodiment and can be implemented in various forms. For example, in the above embodiment, it is determined that the boiling water has boiled when the rate of change in the temperature detected by the temperature sensor 19 becomes smaller than the threshold value. It may be determined that the hot water has boiled when the temperature exceeds (for example, 99.5 ° C.). Further, the control examples shown in FIGS. 4 to 8 may be appropriately combined and implemented.

[0070]

As described above, according to the electric pot of the present invention, when the power cord is once disconnected and then reconnected, the hot water temperature is sufficiently high (not cooled). In this case, the control unit does not start from the water heating mode but immediately enters the heat retention mode. Therefore, unnecessary boiling is not performed and an energy saving effect is obtained.

Further, in a preferred configuration, the control unit is
When the water boiling control is performed, the heat retention temperature is set based on the detected temperature during boiling, so the effects of temperature sensor variations and atmospheric pressure (boiling point) fluctuations are mitigated, and unnecessary boiling is less likely to occur, and , As high as possible (98 ℃
The temperature control is performed at a temperature close to.

[Brief description of drawings]

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

FIG. 2 is a plan view showing an example of an operation panel.

FIG. 3 is a block diagram of a main part of an electric circuit including a microcomputer board, a power supply board, and other electrical components.

FIG. 4 is a flowchart showing a first example of control after reset executed by a control unit.

FIG. 5 is a flowchart showing a second example of control after reset executed by the control unit.

FIG. 6 is a flowchart showing a third example of control after reset executed by the control unit.

FIG. 7 is a flowchart showing a fourth example of control after reset executed by the control unit.

FIG. 8 is a flowchart showing a fifth example of control after reset executed by the control unit.

[Explanation of symbols]

11 pot body 12 Lid 13 Inner container 14 heater 14a Water heater 14b Heat insulation heater 19 Temperature sensor 33 Operation panel 51 control unit

Claims (7)

[Claims] 1. A pot body having an inner container and a heater,
A lid attached to the upper portion of the pot body to open and close the upper opening of the inner container, a temperature sensor for detecting the temperature of the liquid contained in the inner container, and a temperature detected by the temperature sensor. An electric circuit including a heater and the controller via a power cord having a connecting portion that is easily detached from the pot body. An electric pot to which electric power is supplied, the control unit checks the temperature detected by the temperature sensor in an initial process after energization, and if the detected temperature is equal to or higher than a first temperature close to a boiling temperature, Insulation control is performed at a second temperature that is lower than the first temperature by a certain temperature, and when the detected temperature is lower than the first temperature, the insulation control is performed after the boiling water control is performed. An electric kettle characterized by. 2. The control unit checks the temperature detected when the temperature sensor is boiling when performing the boiling water control, and performs the heat retention control at a temperature obtained by subtracting a predetermined difference temperature from the temperature detected when the water is boiled. The electric pot according to claim 1, which is performed. 3. A pot body having an inner container and a heater,
A lid attached to the upper portion of the pot body to open and close the upper opening of the inner container, a temperature sensor for detecting the temperature of the liquid contained in the inner container, and a temperature detected by the temperature sensor. An electric circuit including a heater and the controller via a power cord having a connecting portion that is easily detached from the pot body. An electric pot to which electric power is supplied, the control unit checks the temperature detected by the temperature sensor in an initial process after energization, and if the detected temperature is equal to or higher than a predetermined temperature close to the boiling temperature, the detection is performed. Insulation control is performed at a temperature obtained by subtracting a predetermined temperature difference from the temperature.If the detected temperature is lower than the predetermined temperature, the insulation control is performed after boiling water control. An electric kettle characterized by. 4. The control unit checks a temperature detected when the temperature sensor is boiling when the water boiling control is performed, and determines a temperature obtained by subtracting a difference temperature larger than the difference temperature from the temperature detected when boiling. The electric pot according to claim 3, wherein heat retention control is performed. 5. A pot body having an inner container and a heater,
A lid attached to the upper portion of the pot body to open and close the upper opening of the inner container, a temperature sensor for detecting the temperature of the liquid contained in the inner container, and a temperature detected by the temperature sensor. Based on the electric circuit including the heater and the control unit via a power cord having a connection part that is easily detached from the pot body, An electric pot to which electric power is supplied, the control unit checks the temperature detected by the temperature sensor in an initial process after energization, and if the detected temperature is equal to or higher than a first temperature close to a boiling temperature, Insulation control is performed at a temperature obtained by subtracting the first difference temperature from the detected temperature, and if the detected temperature is a temperature between the first temperature and a second temperature lower than that, the detected temperature is detected. Temperature is a temperature obtained by subtracting a second difference temperature smaller than the first difference temperature from the temperature, and when the detected temperature is lower than the second temperature, the heat retention control is performed after performing the boiling water control. A characteristic electric pot. 6. The control unit checks the temperature detected when the temperature sensor is boiling when the water boiling control is performed, and a third difference larger than the first difference temperature is detected from the temperature detected when boiling. The electric pot according to claim 5, wherein the heat retention control is performed at a temperature obtained by subtracting the temperature. 7. A pot body having an inner container and a heater,
A lid attached to the upper portion of the pot body to open and close the upper opening of the inner container, a temperature sensor for detecting the temperature of the liquid contained in the inner container, and a temperature detected by the temperature sensor. An electric circuit including a heater and the controller via a power cord having a connecting portion that is easily detached from the pot body. An electric pot to which electric power is supplied, wherein the control unit checks the temperature detected by the temperature sensor when a low-temperature heat retention mode in which the heat retention control is performed at a heat retention temperature of approximately 90 ° C. or lower is selected, If the detected temperature is equal to or higher than a predetermined temperature which is lower than the heat retention temperature by a certain temperature, only the water heater or the heat retention heater of the heater Energized, if the detected temperature is lower than the predetermined temperature electric kettle, characterized in that energizing both said kettle heater and insulation heater.