JP2001046229A - Electric hot water storage vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To precisely judge the occurrence of boiling by judging boiling by using two judging indexes. SOLUTION: In the electric hot water storage vessel, temperature of an inner vessel is sensed by a temperature sensor 13. The vessel is heated until the temperature of the vessel sensed by the sensor 13 becomes To, following which the vessel is further heated, and when the temperature of the vessel sensed by the sensor 13 becomes higher than a predetermined set temperature Ts after the lapse of the time it may take for water in the vessel to boil, it is judged that the water has boiled.

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, and more particularly to a method for determining boiling in an electric hot water storage container.

[0002]

2. Description of the Related Art Conventionally, as a method for judging boiling in an electric hot water storage container, a method of detecting water vapor or a method of judging boiling when the rate of rise of the inner vessel temperature or the temperature gradient detected by the temperature detecting means becomes equal to or lower than a set value is used. And so on.

[0003]

However, in the former case, it is necessary to provide a sensor for detecting water vapor in a vapor passage provided in a lid or the like, and wiring of a signal line to the sensor is made between the lid and the main body. There was a problem that it was necessary during.

In the latter case, since only the rate of temperature rise or temperature gradient is used as an index, when the steam-saving control method for reducing the output of the heating means to suppress the amount of generated steam is employed, the main body is not used. There is a possibility that the microcomputer makes an erroneous determination before the actual boiling due to the variation or the like.

[0005] The present invention has been made in view of the above points, and has as its object to perform accurate boiling determination by performing boiling determination using two determination indices.

[0006]

According to the first aspect of the present invention, as a means for solving the above-mentioned problems, an inner container for storing hot water, a heating means for heating the inner container, and detecting a temperature of the inner container are provided. A heating time for calculating a heating time at which water in the inner container will reach boiling from the time when the temperature detected by the temperature detecting means reaches a predetermined temperature. Calculating means, and boiling determining means for determining that boiling has occurred when the temperature detected by the temperature detecting means at the time when the heating time calculated by the heating time calculating means has elapsed is equal to or higher than a preset temperature. Is attached.

[0007] With the above-described structure, when the temperature in the inner container is heated for a heating time at which the water in the inner container will reach boiling from the time when the temperature detected by the temperature detecting means reaches a predetermined temperature, the temperature detecting means Is determined as boiling when the temperature detected by the above becomes equal to or higher than a preset temperature. That is, since the boiling determination is performed based on the elapsed time of the heating time and the set temperature, the boiling determination with less erroneous determination can be performed.

According to the present invention, as means for solving the above problems, an inner container for storing hot water, a heating means for heating the inner container, and a temperature detecting means for detecting the temperature of the inner container are provided. A temperature rise rate calculating means for calculating a temperature rise rate detected by the temperature detection means, and a temperature rise rate calculated by the temperature rise rate calculation means being a preset rise rate. Boiling determining means for determining boiling when the temperature detected by the temperature detecting means at the time when the temperature becomes equal to or higher than a preset temperature is provided.

With the above arrangement, the temperature detected by the temperature detecting means is set at a point in time when the rate of increase of the temperature detected by the temperature detecting means becomes equal to or less than the preset rising rate. When the temperature becomes equal to or higher than the set temperature, boiling is determined. That is, since the boiling determination is performed based on the two of the temperature rise rate and the set temperature, the boiling determination with less erroneous determination can be performed.

[0010] As in the invention of claim 3, claim 1
The electric hot water storage container according to any one of and 2,
When a heating control unit that reduces the output of the heating unit from the time when the temperature detected by the temperature detection unit reaches a predetermined temperature is provided, the amount of heating from the predetermined temperature to boiling is reduced, The amount of steam discharged during boiling can be reduced.

As in the invention of claim 4, in the electric hot water storage container according to any one of claims 1, 2 and 3, heating by the heating means is continued for a predetermined time after the boiling determination by the boiling determination means. In such a case, boiling can be ensured by additional heating.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

First Embodiment FIGS. 1 to 3 show an electric hot water storage container according to a first embodiment of the present invention.

The electric hot water storage container includes a container body 1 having an inner container 3 for storing hot water, and a lid 2 for opening and closing the container body 1.
And an electric heater 4 serving as a heating means for heating the inner container 3, a pouring passage 5 for discharging hot water in the inner container 3 to the outside, and sending out hot water through the pouring passage 5. And a pump device 6.

The container body 1 includes an outer case 7 made of a synthetic resin forming an outer surface, and the inner container 3 forming an inner peripheral surface.
And an annular shoulder member 8 connecting the outer case 7 and the inner container 3 to each other, and a synthetic resin bottom plate 9 constituting a bottom surface.

The inner container 3 includes a cylindrical inner cylinder 10 made of stainless steel and a cylindrical outer cylinder 11 made of stainless steel.
And a vacuum double container in which a vacuum space 12 is formed between the inner tube 10 and a non-vacuum portion 3a formed only of the bottom of the inner cylinder 10 at the bottom thereof. The non-vacuum part 3a
The electric heater 4 (for example, a mica heater in which a heating element is held on a mica plate) is attached to a lower surface of the heater. Reference numeral 13 denotes a temperature sensor that functions as temperature detecting means for detecting the temperature of the inner container 3.

The lid 2 comprises an upper plate 14 made of synthetic resin and a lower plate 15 made of synthetic resin whose outer peripheral edge is joined to the upper plate 14 by welding. It is openably and closably and detachably supported via a hinge pin 17 with respect to a hinge receiver 16 provided at a rear portion. Sign 1
8 is a steam discharge passage.

A metal cover member 19 is fixed to the lower plate 15 of the lid 2.
Is provided with a seal packing 21 which is pressed against the water supply port 20 of the inner container 3 when the lid 2 is closed.

In FIG. 1, reference numeral 22 denotes an operation panel having various switches to be described later, and 23 denotes a control board.

As shown in FIG. 2, the operation panel 22 is provided with a hot water supply switch 24, an unlock switch 25, a cup timer 26, a reboil switch 27, a heat retention selection switch 28, and the like.

FIG. 3 is a block diagram showing a configuration of a main part of the control board 23, wherein reference numeral 4 denotes an electric heater, 13 denotes a temperature sensor constituted by a thermistor or the like, and 27 denotes a reboiler switch.

Reference numeral 29 denotes a microcomputer unit (hereinafter abbreviated as a microcomputer), which internally includes a processing unit CPU, a memory RAM, and a program memory RO.
M, input port A having analog / digital conversion function
/ D, an output port for outputting a control output signal, and the like. The output from the temperature sensor 13 is input to an analog / digital conversion input port A / D of the microcomputer 29. The microcomputer 29 has an interrupt signal input terminal INT.
When an interrupt signal is input to the CPU, an interrupt process is performed.

Reference numeral 34 denotes a zero-cross detection circuit of the commercial AC power supply 33, which sends out a signal at the moment when the sine wave of the commercial AC power supply 33 becomes 0 V, and outputs a timer interrupt signal to an interrupt signal input terminal INT of the microcomputer 29. give. When receiving the timer interrupt signal, the microcomputer 29 measures 10 seconds by counting the internal timer. The output signal of the temperature sensor 13 is fetched every 10 seconds, converted into temperature data, and sequentially stored in the internal memory.

The microcomputer 29 is provided with the temperature sensor 1
3 is the predetermined temperature T₀Reached
Heating time when water in the inner container 3 will reach boiling
ta as a heating time calculating means,
The heating time ta calculated by the heating time calculating means elapses.
The temperature detected by the temperature sensor 13 at the time
Boiling when T exceeds preset temperature Ts
Function as boiling determination means for determining
The temperature T detected by the circuit 13 is a predetermined temperature T ₀Reached
From the time when the output of the electric heater 4 is reduced.
It has a function as control means.

Reference numeral 30 denotes a light emitting diode of the display means, 3
Reference numeral 1 denotes a buzzer as a notification means. The light emitting diode 30 and the buzzer 31 perform display or display of an amount of water contained in the inner container 3, a display of a warming operation state, an abnormal state display, and the like. .

Reference numeral 32 denotes a relay, and reference numeral 33 denotes a commercial AC power supply. The output from the microcomputer 29 allows the relay 32
Is controlled, the heating power applied to the electric heater 4 from the commercial AC power supply 33 is controlled.

Next, the boiling determination control in the electric hot water storage container having the above configuration will be described with reference to flowcharts shown in FIGS. 4 and 5 and a time chart shown in FIG.

(I) Boiling determination control (refer to the flowchart in FIG. 4) If it is determined in step S1 that boiling is occurring (that is, the electric heater 4 is fully energized), step S2 is performed.
In, temperature information from the temperature sensor 13 (that is, the detected temperature T) is input to the microcomputer 29. The comparison between the detected temperature T and the predetermined temperature T ₀ in Step S3 is performed. Here, the predetermined temperature T ₀ is a temperature at which the temperature of the hot water in the inner container 3 becomes uniform (that is, a temperature at which the temperature rise of the hot water becomes constant), for example, 93 ° C. In step S3, T
Boiling heating is continued while <T ₀ is determined,
If it is determined that T ≧ T ₀ , a process of determining the amount of water in the inner container 3 (described in detail later) is performed in step S4. In the water amount determination process, as described later, the output of the electric heater 4 is reduced by a predetermined value (see the time chart of FIG. 6).

On the basis of the result of the water amount determination processing, in step S5, a heating time ta (see the time chart in FIG. 6) at which the water in the inner container 3 will boil from that time is set by a timer. When the count up of the timer is confirmed in S6, the process proceeds to step S6.
At 7, the temperature T detected by the temperature sensor 13 is compared with a preset temperature Ts. Here, the set temperature Ts is a temperature (for example, 99 ° C.) as close as possible to the boiling temperature (for example, 100 ° C.). If it is determined in step S7 that T <Ts, boiling has not yet occurred despite the elapse of the heating time ta. Therefore, in step S8, the water in the inner container 3 reaches boiling from the water amount and the detected temperature T at that time. The heating time ta ′ (see the time chart of FIG. 6) is reset by the timer. However, as shown by the dotted line in the time chart of FIG. 6, when it is determined that T ≧ Ts after the elapse of the heating time ta, In step S9, the boiling notification is performed by the sound of the buzzer 31.

On the other hand, when the timer is reset in step S8, the process returns to step S6 and waits for the timer to count up. In step S7, the detected temperature T is compared with the set temperature Ts, and T ≧ Ts Is repeated until T is determined, but if it is determined that T ≧ Ts, the boiler is sounded by the buzzer 31 in step S9.

[0031] When the boiling notification in step S9 is performed, the output of the electric heater 4 in step S10 is further down, the energization of the electric heater 4 waiting to be judged that the predetermined time t ₁ has elapsed in step S11 Is stopped (see the time chart of FIG. 6). That is,
Is the predetermined time t ₁ only follow the heating is performed. The additional heating after the notification of the boiling is not always necessary, but when the additional heating is performed, the boiling can be more reliably performed.

(II) Water Amount Determination Process (Refer to the Flow Chart of FIG. 5) First, in step S1, the output of the electric heater 4 is reduced by a predetermined value as shown in the time chart of FIG. 6 (for example, 905W to 800W). It is down to intermittent energization). By doing so, the amount of heating from the predetermined temperature T ₀ to boiling is reduced, and the amount of steam discharged during boiling can be reduced.

Next, in step S2, the temperature information (that is, the detected temperature T) from the temperature sensor 13 is input to the microcomputer 29, and in step S3, three detected temperatures Tn (n = 0 to 2) every 10 seconds are obtained. It is stored in the microcomputer 29, and T ₂ -T ₀ is calculated in step S4, and the result is set as the temperature rise x. In steps S5 and S6, the temperature rise x is compared with the set values X ₁ and X _2. Is made. Here, it is assumed that X ₁ > X ₂ . Step S5
If it is determined that x ≦ X ₁ in step S7, step S7
Water = W ₁ (i.e., mass) in is determined, X ₁ <If it is determined that x ≦ X ₂ in step S6, it is determined that water = W ₂ in step S8 (i.e., medium heavy), step If x> X ₂ is determined in S6, it is determined in step S9 that the water amount = W ₃ (that is, a small amount).

As described above, in the present embodiment, the heating time ta at which the water in the inner container 3 will reach boiling from the time when the temperature T detected by the temperature sensor 13 reaches the predetermined temperature T _0. When the temperature T detected by the temperature sensor 13 at the time of heating only becomes equal to or higher than a preset set temperature Ts, it is determined that boiling has occurred. That is, since the boiling determination is performed based on the elapsed time of the heating time ta and the set temperature Ts, the boiling determination with less erroneous determination can be performed.

Second Embodiment FIGS. 7 and 8 show a flowchart of boiling determination control and boiling determination processing in an electric hot water storage container according to a second embodiment of the present invention.

In this case, the microcomputer 29 has a function as a temperature rise rate calculating means for calculating a rise rate α of the temperature T detected by the temperature sensor 13, and a temperature rise rate α calculated by the temperature rise rate calculation means. A function as a boiling determination means for determining that when the temperature T detected by the temperature sensor 13 at the time when the temperature becomes equal to or less than a preset set rise rate A becomes equal to or more than the preset set temperature Ts, And a function as heating control means for reducing the output of the electric heater 4 when the temperature T detected by the temperature sensor 13 reaches a predetermined temperature T ₀ . Other configurations are the same as those in the first embodiment, and a description thereof will be omitted.

Next, the determination of boiling in the present embodiment will be described with reference to the flowcharts shown in FIGS.
This will be described with reference to the time chart shown in FIG.

(I) Boiling determination control (refer to the flowchart of FIG. 7) If it is determined in step S1 that boiling is being performed (that is, the electric heater 4 is being fully energized), step S2 is performed.
In, temperature information from the temperature sensor 13 (that is, the detected temperature T) is input to the microcomputer 29. The comparison between the detected temperature T and the predetermined temperature T ₀ in Step S3 is performed. Here, the predetermined temperature T ₀ is a temperature at which the temperature of the hot water in the inner container 3 becomes uniform (that is, a temperature at which the temperature rise of the hot water becomes constant), for example, 93 ° C. In step S3, T
Boiling heating is continued while <T ₀ is determined,
If it is determined that T ≧ T ₀ , a boiling determination process (described in detail later) is performed in step S4. In the boiling determination process, as will be described later, the degree of increase α of the detected temperature T is a predetermined value A
This is performed depending on whether or not: In the boiling determination process, as described later, the output of the electric heater 4 is reduced by a predetermined value (see the time chart of FIG. 9).

If it is determined in step S5 that the boiling determination process has been completed, the detected temperature T of the temperature sensor 13 is compared with a preset set temperature Ts in step S6. Here, the set temperature Ts is a temperature as close as possible to the boiling temperature (for example, 100 ° C.) (for example, 99 ° C.).
° C). If it is determined in step S6 that T <Ts, it is determined that the boiling has not actually occurred in spite of the determination of boiling in the boiling determination process.
7, the boiling determination data is cleared, the process returns to step S2, and the subsequent control is repeated. If it is determined in step S6 that T ≧ Ts, boiling notification is performed by the buzzer 31 in step S8.

[0040] When the boiling notification in step S8 is performed, the output of the electric heater 4 at step S9 is further down, the energization of the electric heater 4 waiting to be judged that the predetermined time t ₁ has elapsed in step S10 Is stopped (see the time chart of FIG. 9). That is, the predetermined time t ₁ follow the heating is performed. The additional heating after the notification of the boiling is not always necessary, but when the additional heating is performed, the boiling can be more reliably performed.

(II) Boiling determination process (refer to the flowchart of FIG. 8) First, in step S1, the output of the electric heater 4 is reduced by a predetermined value as shown in the time chart of FIG. 9 (for example, from 905 W to 800 W). It is down to intermittent energization). By doing so, the amount of heating from the predetermined temperature T ₀ to boiling is reduced, and the amount of steam discharged during boiling can be reduced.

Next, in step S2, the temperature information (that is, the detected temperature T) from the temperature sensor 13 is input to the microcomputer 29, and in step S3, four detected temperatures Tn (n = 0 to 3) every 10 seconds are obtained. It is stored in the microcomputer 29, and it is determined in step S4 whether or not the calculation of x = T ₂ −T ₀ has already been performed. If a negative determination is made here, the process proceeds to step S5, where x = T ₂ −T ₀ is calculated, and based on the result, the set value A is set in step S6. Step S7 calculation of the temperature rise rate y = T ₃ -T ₀ is made in comparison with the set value A and the temperature increase rate y is made at step S8.

The set value A is a slope at a point P where the slope of the temperature rise line Z in the time chart of FIG. 9 changes greatly. The reason is that as the temperature approaches boiling, the rate of temperature rise changes greatly (ie, approaches 0).

If it is determined in step S8 that y ≦ A, the boiling flag is set, and the boiling determination processing ends.

When an affirmative determination is made in step S4, the process directly proceeds to step S7, and the following control is executed.

As described above, in the present embodiment, the temperature detected by the temperature sensor 13 at the time when the rate of increase y of the temperature T detected by the temperature When T becomes equal to or higher than the preset temperature Ts, it is determined that boiling has occurred. That is, since the boiling determination is performed based on the two of the temperature rise rate α and the set temperature Ts, the boiling determination with less erroneous determination can be performed.

[0047]

According to the first aspect of the present invention, there is provided an electric hot water storage container including a hot water storage container, heating means for heating the internal container, and temperature detecting means for detecting the temperature of the internal container. A heating time calculating means for calculating a heating time at which the water in the inner container will reach boiling from the time when the temperature detected by the temperature detecting means reaches a predetermined temperature; and a heating time calculating means for calculating the heating time. Boil determination means for determining boiling when the temperature detected by the temperature detection means at the time when the heating time has elapsed is equal to or higher than a preset temperature, is detected by the temperature detection means. Boiling when the temperature detected by the temperature detecting means becomes equal to or higher than a preset temperature at the time when the water in the inner container is heated for a heating time that would cause the water in the inner container to boil from the time when the temperature reaches the predetermined temperature. Since to be determined, the boiling determination becomes a be performed two and elapsed and the set temperature of the heating time basis, there is an effect that it is possible to perform the low boiling determination of erroneous determination.

According to the second aspect of the present invention, there is provided an electric hot water storage container including a hot water container, a heating means for heating the inner vessel, and a temperature detecting means for detecting a temperature of the inner vessel. Temperature rising rate calculating means for calculating a temperature rising rate detected by the temperature detecting means; and a temperature rising rate calculated by the temperature rising rate calculating means when the temperature rising rate becomes equal to or less than a preset rising rate. Boiling judgment means for judging boiling when the temperature detected by the temperature detection means is equal to or higher than a predetermined set temperature, and the rate of rise of the temperature detected by the temperature detection means is set at a preset value. Since the temperature detected by the temperature detecting means at the time when the temperature rise rate is equal to or less than the preset temperature is determined to be boiling, the boiling determination is performed based on the temperature increase rate and the set temperature. Will be performed two basis, there is an effect that it is possible to perform the low boiling determination of erroneous determination.

As in the invention of claim 3, claim 1
The electric hot water storage container according to any one of and 2,
If a heating control means for reducing the output of the heating means from the time when the temperature detected by the temperature detection means reaches a predetermined temperature is added, the amount of heating from the predetermined temperature to boiling will be reduced, The amount of steam discharged during boiling can be reduced.

As in the invention of claim 4, in the electric hot water storage container according to any one of claims 1, 2 and 3, heating by the heating means is continued for a predetermined time after the boiling determination by the boiling determination means. In such a case, boiling can be ensured by additional heating.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an electric hot water storage container according to a first embodiment of the present invention.

FIG. 2 is a plan view of an operation panel in the electric hot water storage container according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing a main part of a control board in the electric hot water storage container according to the first embodiment of the present invention.

FIG. 4 is a flowchart showing the content of boiling determination control in the electric hot water storage container according to the first embodiment of the present invention.

FIG. 5 is a flowchart showing the contents of a water amount determination process in the electric hot water storage container according to the first embodiment of the present invention.

FIG. 6 is a time chart showing a change in temperature and a change in output of the electric heater during boiling control in the electric hot water storage container according to the first embodiment of the present invention.

FIG. 7 is a flowchart showing the content of boiling determination control in the electric hot water storage container according to the second embodiment of the present invention.

FIG. 8 is a flowchart showing the content of a boiling determination process in the electric hot water storage container according to the second embodiment of the present invention.

FIG. 9 is a time chart showing a change in temperature and a change in output of an electric heater during boiling control in the electric hot water storage container according to the second embodiment of the present invention.

[Explanation of symbols]

3 is an inner container, 4 is a heating means (electric heater), 13 is a temperature detecting means (temperature sensor), and 29 is a microcomputer.

Claims (4)

[Claims] 1. An electric hot water storage container comprising an inner container for storing hot water, heating means for heating the inner container, and temperature detecting means for detecting a temperature of the inner container, wherein the electric temperature is detected by the temperature detecting means. Heating time calculating means for calculating a heating time at which the water in the inner container will reach boiling from the time when the temperature reached the predetermined temperature, and a time when the heating time calculated by the heating time calculating means elapses And a boiling judging means for judging a boiling when the temperature detected by the temperature detecting means in step 1 is equal to or higher than a preset temperature. 2. An electric hot water storage container comprising an inner container for storing hot water, heating means for heating the inner container, and temperature detecting means for detecting a temperature of the inner container, wherein the electric water storage container detects the temperature by the temperature detecting means. A temperature rise rate calculating means for calculating a temperature rise rate calculated by the temperature detecting means; and a temperature detection means for detecting the temperature rise rate when the temperature rise rate calculated by the temperature rise rate calculation means becomes equal to or less than a preset rise rate. An electric hot water storage container provided with boiling determination means for determining boiling when the set temperature becomes equal to or higher than a preset temperature. 3. A heating control means for reducing the output of said heating means when the temperature detected by said temperature detecting means reaches a predetermined temperature is provided. An electric hot water storage container according to claim 1. 4. The electric hot water storage container according to claim 1, wherein heating by the heating means is continued for a predetermined time after the boiling determination by the boiling determination means. .