JPH06141974A - Electric type hot water storing vessel - Google Patents

Abstract

(57) [Summary] [Purpose] To maintain the temperature of the content liquid within a predetermined temperature range with a simple and low-cost configuration without energization control of the heat retention heater. [Structure] While in the heat retention mode, the heat retention heater is continuously energized with a fixed capacity, and when the content liquid temperature is lowered to a predetermined lower limit temperature, the water heater is also energized to execute the water boiling mode, and the content liquid is predetermined. It is characterized in that control means for stopping the water heating mode when the temperature is raised to the return temperature is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric hot water storage container such as an electric pot used at home. More specifically, it is equipped with a water heater and a heat-retaining heater, and a boiling water mode for boiling the content liquid and a predetermined content liquid are provided. The present invention relates to an electric hot water storage container that executes a heat retention mode of keeping temperature.

[0002]

2. Description of the Related Art An electric kettle and a heat-retaining heater are energized in an electric pot of this type to execute a water-boiling mode. To do
There is known a type in which the heat retention heater has a fixed capacity that balances with the natural temperature drop of the content liquid, and the heat retention heater continues to be energized at the fixed capacity following the water heating mode.

However, in this case, the amount of the content liquid, the season,
The temperature lowering characteristic of the content liquid varies depending on the room temperature which differs in regions, etc., and it is difficult to keep the content liquid in a predetermined temperature range.

For this reason, the content liquid is often lower than a predetermined temperature range, which makes the user dissatisfied with the content liquid without knowing such a temperature drop.

To solve this problem, a control circuit as shown in FIG. 7 has been developed and put into practical use.

As shown in the figure, this device is configured such that energization of both the water heater a and the heat retaining heater b is controlled by the microcomputer c.

In controlling the energization of the heat retaining heater b, the current temperature of the content liquid is fed back, and the conduction capacity of the heat retaining heater b is controlled by controlling the conduction angle of the triac e via the transistor d according to this temperature information. It is adjusted so that the content liquid is kept within a predetermined temperature range.

Therefore, the contents liquid can be forcibly maintained within a predetermined temperature range even if the amount of contents liquid or room temperature is affected.

[0009]

However, such control of the heat-retaining heater increases the required capacity of the microcomputer and requires a control element or device such as a triac or transistor for control. The cost is higher than that of a heater that does not control energization.

Further, the circuit board also becomes large and complicated due to the mounting of the triac and the transistor, which also causes a high cost, and it is difficult to install the circuit board in a small space in the electric pot, resulting in a degree of freedom in design. Is low.

Therefore, the present invention follows the method of executing the heat retention mode without controlling the energization of the heat retention heater, and prevents the content liquid from being extremely cooled without impairing the low cost aspect thereof. By avoiding dissatisfaction with the user, and by displaying the heat insulation status as necessary, the user can take necessary temperature raising measures beforehand, which is convenient for use. It is an object of the present invention to provide an electric hot water storage container.

[0012]

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention comprises a water heater and a heat-retaining heater, and a water-heating mode for boiling the content liquid and a heat-retaining method for maintaining the content liquid at a predetermined temperature. In the electric hot water storage container that executes the mode and in the warming mode, the warming heater continues to be energized with a fixed capacity, and when the content liquid temperature drops to a predetermined lower limit temperature, the boiling water heater is also energized to set the boiling mode. It is characterized in that it is provided with control means for executing the operation and stopping the water heating mode when the temperature of the content liquid rises to a predetermined reset temperature.

The predetermined return temperature may be a boiling temperature, and a display means for displaying the heat retention temperature state of the content liquid may be further provided.

The display means indicates that the content liquid temperature is lower than the heat retention temperature at least when the content liquid reaches a predetermined intermediate temperature lowering temperature between a predetermined heat retention temperature and a predetermined lower limit temperature. It is preferable to display it.

[0015]

In the above-mentioned structure of the present invention, in the heat retention mode, the heat retention heater is continuously energized with a predetermined fixed capacity,
The content liquid is heated to a minimum to keep it warm, but the temperature may be lowered to a predetermined lower limit temperature depending on the amount of the content liquid and the room temperature. At this time, the control means also energizes the kettle heater to execute the kettle mode, and stops the kettle mode when the temperature of the content liquid rises to the predetermined return temperature, so that the content liquid is heated without energization control of the heat retention heater. By adding a little control program to the control means for controlling energization of the heater, it is possible to recover to a predetermined return temperature and keep the content liquid within a preset temperature range.

When the predetermined return temperature is the boiling temperature, the content liquid is automatically returned to the boiling state every time the temperature of the liquid content is lowered to the lower limit temperature.

When the heat-retaining temperature state of the content liquid is displayed by the display means, the user can be notified of the heat-retaining state and the user can be prompted to use and take measures accordingly.

When the display means displays that the content liquid has reached a predetermined intermediate temperature lowering temperature between a predetermined heat retaining temperature and a predetermined lower limit temperature, the user is informed of the intermediate temperature lowering temperature state and necessary. It is possible to prompt the user to take measures such as a water heating mode according to the above.

[0019]

EXAMPLES Examples of the present invention will be described below.

FIG. 1 shows the overall construction of a household electric pot as a first embodiment to which the present invention is applied.

As shown in FIG. 1, an inner container 2 is housed in an outer case 3 to form a container body 1 of an electric hot water storage container.

The upper end flange of the inner container 2 is received by a shoulder member 4 made of synthetic resin which is forcibly fitted to the upper end of the outer case 3.

A bottom ring 7 made of synthetic resin is applied to the lower end of the outer case 3, and the bottom ring 7 and the bottom of the inner container 2 are connected by a connecting fitting (not shown) to form the outer case 3 and the inner container 2. And the bottom ring 7 are integrated with each other.

A bottom lid 10 is attached to the opening of the bottom ring 7 by fitting a plurality of claws provided on the bottom lid 10 and screwing at one location.

A rotary seat body 9 is rotatably fitted on the outer peripheral portion of the lower surface of the bottom lid 10 by a plurality of claws provided on the bottom cover 10, and when the body body 1 is stationary, it is mounted on the rotary seat body 9. 1
Can be rotated lightly.

A bottom heater 8 is provided on the bottom surface of the bottom of the inner container 2.
a and 8b are applied. This bottom heater 8a, 8
Reference numeral b denotes a water heater and a heat-retaining heater. For example, the wire bottom heaters 8a and 8b are alternately wound around an annular mica plate, sandwiched between the mica plates, and housed in a case.

A heat shield plate 32 is fixed to the bottom of the bottom of the inner container 2 with a metal fitting 31, and a presser 35 is sandwiched between the heat shield plate 32 and the back side of the bottom heaters 8a and 8b. Thereby, the bottom heaters 8a and 8b are pressed against the bottom surface of the bottom of the inner container 2. The pouring pump 11 is attached to a part of the heat shield plate 32.

A temperature sensor 33 for sensing the temperature of the content liquid is provided in a through hole at the center of the bottom heaters 8a and 8b, and is thermally isolated from the bottom heaters 8a and 8b by a heat shield wall 34.

The bottom ring 7 is provided with a circuit accommodating box 40 opened downward, and a circuit board 41 accommodated in the circuit accommodating box 40 is waterproof against water leakage from above.

At the upper end of the body 1, the body 1 formed by the shoulder member 4
A body lid 6 for covering the mouth portion of the container is provided. The container lid 6 is pivotally attached to the shoulder member 4 at the rear portion thereof by a hinge pin 68 so as to be openable and closable. This container lid 6 is pivotally attached to the shoulder member 4
This is performed for the bearing 69 integrally formed with the hinge 69 so that the hinge pin 68 can be attached to and detached from the bearing 69 when the body lid 6 is open.

By attaching and detaching the hinge pin 68, the container lid 6 can be attached and detached, which facilitates cleaning of the inside of the container 1 and supply and discharge of the content liquid.

A lock member 71 is provided at the free end of the body lid 6 to advance and retract the upper surface of the back plate 81 of the body lid 6 to lock the body lid 6 in the closed state.

The lock member 71 elastically engages with the engagement hole formed in the shoulder member 4 by the bias of the spring, and keeps the body lid 6 closed with respect to the shoulder member 4.

The cam portion of the lock release lever 79 comes into contact with the rear end portion of the lock member 71, and the lock release lever 79 is pulled up, whereby the lock member 71 is resisted against the spring by the cam portion. The lock release lever 7 is retracted from the engagement position to release the lock of the body lid 6 to the closed position.
By further pulling up 9, the body lid 6 can be opened following unlocking.

On the lower surface of the back plate 81 of the vessel lid 6, the inner container 2
A metal inner lid 85 that closes the rear of the
It is screwed at 3. Outer periphery of inner lid 85 and back plate 81
A seal punk 84 that faces the rim of the inner lid 85 is sandwiched between the inner lid 85 and the inner lid 85. , The inner container 2 is closed.

The inner container 2 is provided between the back plate 81 and the inner lid 85.
A steam passage 87 is provided to allow steam generated inside to escape to the outside.

This steam passage 87 has an opening 86 to the inner container 2 side in the inner lid 85, and has an opening 52 to the outside on the upper surface of the rear side of the body lid 6. A valve chamber 91 accommodating the water shutoff valve 92 at the time of falling is provided at a position near the opening 86.

A pouring path 12 for pouring out the content liquid is connected to the bottom of the inner container 2. The spouting path 12 rises up to the inside of the beak-shaped protrusion 5 provided in the front portion of the shoulder member 4 in the space between the inner container 2 and the outer case 3 to spout the spout 1
9 stop valve immediately before this connection part 1
4 are provided.

The beak-shaped protruding portion 5 projects from the shoulder member 4, and a passage cover 15 forming a part of the beak-shaped protruding portion 5 is fitted in the downward opening to cover the spout pipe 19. .

The passage cover 15 includes a lower cover 15a.
The liquid injection guide 16 is integrally formed, and the discharge port tube 19 is covered with the outer surface of the body 1 and the discharge port 19 is also formed.
a is facing downward.

At the portion of the spout 12 below the inner container 2, the content liquid flowing into the spout 12 is discharged.
A pouring pump 11 for feeding to 9a is provided and driven by a small DC motor 101 of low voltage.
Although not shown, the rising portion of the pouring path 12 serves as a liquid amount detecting unit for detecting the liquid amount of the content liquid by the capacitance.

Control circuit 42 having the circuit board 41
The microcomputer 43 utilizes a boiling water mode for initially boiling the content liquid, a heat retention mode for automatically keeping the content liquid after the initial boiling within a predetermined temperature range, re-boiling from the heat retention mode state, and a boiling state after the initial boiling. By keeping the value for a certain time, the descaling mode for descaling can be performed. Further, the DC motor 101 is driven in accordance with the operation of pouring out the content liquid so that the content liquid is poured out.

The drive circuit for the bottom heaters 8a and 8b is as shown in FIG. 2, and the bottom heater 8a for boiling water is energized and controlled by the relay contact 131a of the relay 131 controlled by the microcomputer to keep the bottom heater warm. 8b is designed to continue to be energized with a fixed capacity without energization control in both the water heating mode and the heat retention mode.

FIG. 3 shows an operation panel 17 provided on the upper surface of the beak-shaped protrusion 5. In the present embodiment, the operation panel 17 is provided with a pouring key 141 for pouring out the content liquid, and a selection key 142 for alternately setting re-boiling and descaling, which are arranged on the back surface of the operation panel 17. The respective display LEDs 120 to 122 for displaying boiling, heat retention, and descaling installed on the operation circuit board 18 face.

Bottom heater 8 for boiling water and for keeping heat
a and 8b are both energized to execute the water heating mode or the reboiling mode, and only the bottom surface heater 8b for heat retention is energized with a fixed capacity to execute the heat retention mode. When the capacity is set to 905 W and the bottom heater 8b for heat retention is set to 40 W, there is no significant difference in the temperature rising characteristics in the water heating mode that would hinder practical use, but the temperature of the content liquid in the heat retention mode is affected by room temperature. When greatly received, a large difference occurs as shown in FIG.

For example, when the room temperature is relatively high at 35 ° C. and 20 ° C., the temperature lowering characteristic of the content liquid and the temperature raising characteristic by the heating of the bottom heater 8b for heat retention are roughly balanced, and the content liquid becomes
As shown by the line (1), it stabilizes at a temperature of 90 ° C. or higher.

However, when the room temperature reaches 10 ° C. and 5 ° C.,
As shown by the line in, the content liquid falls below 90 ° C
Cool down to about ℃.

In this embodiment, the lower limit temperature for keeping the content liquid at 80 ° C. is set as the lower limit temperature, and the reboil mode is executed so as to reboil the content liquid when this temperature is reached, so that the bottom heater 8b for keeping heat is energized. Microcomputer 4 without
A little control is added to the program for controlling the bottom heater 8a for boiling water, and the content liquid is kept warm in the range of 80 ° C to boiling only by performing the energization difference control as shown by the phantom line in FIG. be able to. Therefore, it is possible to avoid the user's dissatisfaction due to the extremely low temperature of the content liquid.

However, because the content liquid is often used to make coffee, green tea or black tea, the above 90 ° C.
Even at the temperature of, the user often feels dissatisfied when the content liquid is cold in many cases.

Therefore, in the heat retention mode, the content liquid temperature is 90 ° C.
When the temperature is above, the heat-retaining LED 121 is turned on to indicate that it is in a normal heat-retaining state, and when the content liquid temperature falls below 90 ° C., this is indicated by blinking of the heat-retaining LED 121,
Notify the user that the temperature of the content liquid is low, and
Encourage reboil operation if necessary.

As a result, it is possible to avoid the content liquid being poured out and used without knowing that the content liquid is lower than 90 ° C., and to avoid the user's complaints. Etc. can be made without failure. FIG. 4 shows such specific control.
It becomes like the flowchart shown in.

The second embodiment of the present invention shown in FIG.
The difference between the heat retaining states is made clear by turning on the orange heat retaining LED in the normal heat retaining state of not less than 0 ° C. and turning on the green heat retaining LED in the heat retaining state of lower than 90 ° C.

It will be clearer if the display of characters is combined with the lighting of the heat retaining LEDs of different colors, and when the green heat retaining LEDs are blinked, it can be seen that the content liquid has fallen below 90 ° C. It has the advantage that it is easy for users to notice.

The lower limit temperature of the heat retention can be set freely. In order to recover the temperature of the content liquid that has reached the lower limit temperature, if you execute the re-boiling mode as described above and return the content liquid to the boiling state, you can immediately pour out the boiling content liquid and use it. Is more convenient to use.

[0055]

According to the present invention, in the heat retention mode, the content liquid is kept warm without keeping the energization control of the heat retention heater by continuing to energize the heat retention heater at a predetermined fixed capacity. When the temperature is lowered to a predetermined lower limit temperature, the water heater is energized to restore the content liquid to a predetermined return temperature, so without energizing the warming heater,
The content liquid can be kept within a preset temperature range with a simple and low-cost configuration by simply adding a small program to the control means for controlling the energization of the water heater. It can be avoided that the user is dissatisfied with the temperature being extremely lowered or that it takes time to notice the low temperature and return to the predetermined temperature.

When the predetermined return temperature is the boiling temperature, the content liquid is automatically returned to the boiling state every time the temperature is lowered to the lower limit temperature, so that there are many opportunities to immediately pour the content liquid in the boiling state, which can be used. It is convenient for

When the heat-retaining temperature state of the content liquid is displayed by the display means, the heat-retaining state is notified to the user and the user can be prompted to use and take measures accordingly. It is easy to guarantee that it will be used as it is, and it will be convenient to use.

When the display means indicates that the content liquid has reached a predetermined intermediate cooling temperature between a predetermined warming temperature and a predetermined lower limit temperature, the user is notified of the intermediate cooling temperature state and necessary. Depending on the situation, the user can be prompted to take measures such as a boiling water mode, so that the temperature can be raised to the required temperature even faster in order to guarantee that the device will be used in the required temperature state. , Becomes more convenient to use.

[Brief description of drawings]

FIG. 1 is a sectional view showing an overall configuration of an electric pot as a first embodiment to which the present invention is applied.

FIG. 2 is a block diagram showing a main configuration of a control circuit for the electric pot shown in FIG.

FIG. 3 is a plan view of an operation panel of the electric pot of FIG.

FIG. 4 is a graph illustrating the temperature change of the content liquid when the energization control of the heat retention heater is omitted.

FIG. 5 is a flowchart showing a subroutine of heat retention control in the first embodiment of the present invention.

FIG. 6 is a flowchart showing a subroutine of heat retention control in the second embodiment of the present invention.

FIG. 7 is a block diagram showing a conventional heater control circuit.

[Explanation of symbols]

 8a, 8b Bottom heater 33 Temperature sensor 42 Control circuit 43 Microcomputer 121 Thermal LED

Claims (4)

[Claims] 1. A hot water heater and a heat retention heater are provided,
In an electric hot water storage container that performs a boiling water mode to boil the content liquid and a heat retention mode to keep the content liquid at a predetermined temperature, in the heat retention mode, the heat retention heater is continuously energized with a fixed capacity and the content liquid temperature is set to a predetermined value. When the temperature is lowered to the lower limit temperature, the electric water heater is also energized to execute the electric water heating mode, and the electric heating device is provided with a control means for stopping the electric water heating mode when the temperature of the content liquid rises to a predetermined return temperature. Hot water storage container. 2. The electric hot water storage container according to claim 1, wherein the predetermined return temperature is a boiling temperature. 3. The electric hot water storage container according to claim 1, further comprising display means for displaying a heat-retention temperature state of the content liquid. 4. The display means has a content liquid temperature lower than the heat retention temperature at least when the content liquid reaches a predetermined intermediate temperature lowering temperature between a predetermined heat retention temperature and a predetermined lower limit temperature. The electric hot water storage container according to claim 3, which indicates that.