JPH06133864A - Electric hot-water heater - Google Patents

Abstract

PURPOSE:To make it unnecessary to re-set such operating conditions as boiling and warming, etc., when a service interruption is restored. CONSTITUTION:A storage means 14 is provided, and when a service interruption is detected by a service interruption detecting means 13, a control means 8 stores an operating condition which is set before the service interruption and an operating state before the service interruption in the storage means 14, refers to the stored operating condition and operting state when the service interruption is restored, and executes control corresponding to the operation before the service interruption. The operating condition is operated and set by a timer setting means 9 for setting a downtime until heating is started, a warming temperature setting means 11 for setting a warming temperature, and a boiling mode setting means 12 for setting a mode at the time of boiling, and they are displayed on a display means 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric water heater for heating and retaining the water contained in a container.

[0002]

2. Description of the Related Art In recent years, electric water heaters have become multi-functional and have not only the function of heating and keeping water warm, but also the function of changing several kinds of heat-retaining temperature and a purifying function of making delicious water. It is being developed, but the issue is how to use it during power outages.

A conventional electric water heater will be described below. FIG. 8 is a partial cross-sectional block diagram showing the configuration of a conventional electric water heater. In FIG. 8, an electric water heater main body container 1 is provided with a container 2 having an upper surface opening, and a lid 3 for covering the opening is arranged on an upper part of the container 2. Further, a heating source 4 having a heating heater for heating the water in the container 2 and a heat retaining heater for keeping the temperature, and a temperature sensor 5 for detecting the water temperature in the container 2 are provided below the container 2. It is arranged. The temperature detecting means 6 detects the water temperature from the signal from the temperature sensor 5. The heating source 4 is energized and controlled by the heating / warming control unit 7.

The timer setting means 9 is a means for setting a rest time until the heating heater starts boiling water, and is constituted by, for example, a push switch or the like, and the setting condition is input to the heating / warming control means 7. With respect to the heat retention temperature setting means 11 and the boiling mode setting means 12, the heat retention temperature setting conditions and the boiling mode setting conditions are input to the heating and heat retention control means 7 by the same configuration as described above. The heating and heat retention control means 7 displays the conditions of the down time, the heat retention and the boiling mode by the display means 10. 10a indicates a dwell time, 10aa indicates a light emitting diode (hereinafter referred to as LED) indicating that it takes 2 hours to start boiling water, 10ab indicates an LED for 6 hours, and 10ac indicates 8 hours. Is an LED indicating that. For example, when the power is turned on, all the timer display means 10a are turned off and the heating is set to start immediately, but each time the switch of the timer setting means 9 is pressed once, the rest time is 2 hours, 6 hours. Time, 8 hours, all lights off, 2 hours cyclically switched.

The heat retention temperature setting means 11 displays the heat retention conditions by the heat retention display means 10b of the display means 10. 10 ba
Is an LED that indicates that the temperature is maintained at a high temperature of about 95 degrees C, 10bb is an LED that indicates that the temperature is maintained at about 85 degrees C, and 10bc is that the temperature is maintained at about 70 degrees C. Is an LED that displays. Although the high temperature insulation is set at the time of turning on the power, the insulation temperature setting means 11
Each time you press the switch, the temperature changes to 85 degrees, 70 degrees, and high temperature, and the display LE
D is cyclically switched to 10ba, 10bb, 10bc, and 10ba and lights up.

The boiling mode setting means 12 displays the boiling mode by the boiling mode display means 10c of the display means 10. Reference numeral 10ca indicates a normal boiling mode in which heating is stopped when water boils, and a heat retaining operation is started, and 10cb indicates a mode in which boiling is continued for a predetermined time after boiling. The mode in which boiling continues for a predetermined time corresponds to, for example, a water purification mode in which water is circulated by a pump or the like while being heated to be filtered, circulation is stopped when boiling, and purification is performed by an operation of continuing boiling for a while. Each time the switch of the boiling mode setting means is pressed once, the normal boiling mode 10ca,
The LEDs of the water purification mode 10cb are switched and lighted.
When the power is turned on, the normal boiling mode is set.

The power failure detecting means 13 detects a power failure for a few ms if the power supply voltage drops significantly or the power failure continues for a predetermined time or longer.
After that, a power failure detection is performed and a power failure detection signal is output to the heating / warming control unit 7. When the heating / warming control means 7 receives the power failure detection signal, it immediately turns off the heating display means 10b and the boiling display means 10c and stops the output to the heating source 4 and the circulation means 15. Predetermined time, for example, 2-3
When the power is restored within a second, the driving power supply voltage of the heating / warming control means 7 is held by the electrolytic capacitor or the like.
When the power is restored from the power failure, the set down time condition, the heat retention condition, and the boiling mode condition are maintained.

[0008]

In such a conventional electric water heater, the heating and heat retention control means is used when the power failure time is long or when the water in the container is cut off from the power supply for a long time. Since the driving power supply voltage cannot be maintained, the operating condition disappears, and when the power is turned on again, a new condition must be set, and there is a problem that the operation is troublesome.

The present invention solves the above-mentioned problems. When power is restored from a power failure, the operating conditions and operating conditions before the power failure are automatically set, and the switch is pressed many times when the power is restored or the power is turned on again. An object of the present invention is to provide an electric water heater that does not require a reset operation.

[0010]

In order to achieve the above-mentioned object, the present invention comprises a container for containing a liquid, a heating source for heating the liquid, and a temperature detecting means for detecting the temperature of the liquid. , Operation condition setting means for setting conditions such as boiling and heat retention of the liquid and a dwell time until the start of heating, and a power failure detection to detect that a significant voltage drop or power failure of the power supply has continued for a predetermined time or more as a power failure Means, a storage means, and a control means for controlling heating start, boiling and heat retention operations of the liquid in accordance with the operating conditions, the control means, when the power failure is detected by the power failure detection means, a power failure The previously set operating condition and the operating state before the power failure are stored in the storage means, and the heating and heat retaining operations are controlled by referring to the operating condition and the operating state stored in the storage means when the power is restored. It is an electric water heater, which was to so that.

[0011]

According to the present invention, in the above structure, the control means detects the power failure by the power failure detecting means, stores the operating condition set before the power failure and the operating state before the power failure in the memory means, and restores the power from the power failure. At this time, the heating and heat retaining operations are controlled with reference to the operating conditions and operating states stored in the storage means at the time of power recovery.

[0012]

【Example】

(Embodiment 1) Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a partial sectional block diagram showing the configuration of an electric water heater according to a first embodiment of the present invention. In the figure,
The same components as those of the conventional example shown in FIG. 8 are assigned the same reference numerals and detailed explanations thereof will be omitted. The constituent features of the electric water heater of the present invention different from those of the conventional example are the provision of the storage means 14 and the operation of the control means 8.

In FIG. 1, when the control means 8 detects a power failure by the power failure detection means 13, the control means 8 stores in the storage means 14 the set down time, heat retention temperature, boiling mode, and operating state of boiling or heat retention. . When the power is restored from the power failure, the control means 8 reads out the rest time, the heat retention temperature, the boiling mode, and the operation before the power failure, which were in boiling or heat retention, which are stored in the storage means 14, and the conditions are displayed in the display means 1
While displaying 0, the operation is restarted by referring to those conditions. For example, the heating source 4 and the circulation means 15 are drive-controlled based on the temperature data of the temperature detection means 6. A power failure occurs during operation in the normal boiling mode, and the mode restarts when power is restored after a few hours. Further, if a power failure occurs during heat retention, the temperature data of the temperature detecting means 6 is compared with the stored set temperature data after power recovery, and if the temperature difference is within a predetermined temperature difference, the heat retention is continued. After boiling according to the boiling mode called from the means 14, the temperature is controlled to be kept at the set temperature. Further, the display corresponding to the operation is displayed on the display unit 1.
Perform with 0.

FIG. 2 is a circuit diagram showing the electrical construction of an electric water heater according to an embodiment of the present invention. In the figure, 4a is a heating heater, 4b is a warming heater, 5 is a thermistor which is a temperature sensor, and 6a to 6h are resistors and A which constitute the temperature detecting means 6.
The D / D converters 13a, 13b and 13c are resistors forming the power failure detection means, and 8a, 8b and 8c, 8d and 8
e is a microcomputer, a relay, a thyristor and an electrolytic capacitor, which constitute control means, 9 and 1, respectively.
Reference numerals 1 and 12 respectively denote a timer setting switch as a pause time setting means, a warming temperature setting switch as a warming temperature setting means, and a boiling mode setting switch as a boiling mode setting means, 10a is a timer display means, and 10b is a warming temperature display means. 1, 10c is a boiling mode display means, 14 is a non-volatile memory that constitutes storage means, 15a and 15b are motors and their drive circuits that constitute water circulation means, 17 is an AC power supply, and the block diagram shown in FIG. It corresponds to.

The microcomputer 8a controls the relay coil 8c and the thyristor 8d to control the amount of electricity supplied to the heating heater 4a and the heat retaining heater 4b. In the boiling mode in which water is boiled, the microcomputer 8a connects the relay contact 8b with the relay coil 8c to energize the heater 4a. When the water is kept warm after boiling, the microcomputer 8a operates the thyristor 8d to energize the warm heater 4b. In the water purification mode in which water is circulated to be purified and boiled while being filtered, the microcomputer 8a connects the contact 8b by the relay coil 8c to energize the heater 4a and the motor drive circuit 1
The motor 15a is driven by 5b to circulate the water, and when the water boils, the driving of the motor 15a is stopped, the water is kept boiling for several minutes, and then the heat retaining operation is started. Incidentally, the drive DC power source for the microcomputer 8a and the like is generally generated from an AC power source and loses its drive voltage in the event of a power failure.
Stored charge is used for.

When the voltage of the power supply 17 drops and the power is cut off, the combined voltage of the AC power supply voltage and the predetermined DC voltage is a point A in the figure by the resistor 13a and the resistors 13b and 13c connected to one end of the power supply 17. Then, the voltage is input to the microcomputer 8a to detect zero volt of the AC power supply 17 (hereinafter, referred to as SNS detection in the present invention). FIG. 3 is a timing chart showing the SNS detection operation. In the embodiment, the resistors 13b and 13c have the same resistance value and the predetermined DC voltage is set to 1/2 Vdd. The SNS detection signal is the microcomputer 8
When the signal is input to a, the input signal is clamped by the diode in the microcomputer 8a, so that the waveform becomes the square wave shown in FIG. In addition, (a) shows an AC power supply waveform. In addition, the DC voltage 1/2 Vdd
Assuming reference voltages V1 and V0 above and below, the microcomputer 8a detects a case where the SNS signal has a voltage change waveform crossing the V0 and V1 as shown in FIG. , In the case of other voltage change waveforms, it is detected as "low" level. In the case of a power failure, the SNS signal is 1/2 Vdd and does not cross V0 and V1 and therefore corresponds to the "low" level.

For reference, a detection waveform of the microcomputer 8a corresponding to the SNS signal is shown in FIG. 3 (c). The “high” level of the SNS signal corresponds to a pulse waveform with a width of several hundreds of μs, and the “low” level of the SNS signal corresponds to a trapezoidal waveform. The microcomputer 8a determines that a power failure has occurred if the "low" level continues for several ms.
Note that this operation also occurs when the AC power supply voltage drops significantly.

When the microcomputer 8a detects a power failure, the rest time, boiling mode, and
The storage unit 14 stores data such as a heat retention temperature and whether the operating state at that time is boiling or heat retention. Storage means 1
4 is composed of a non-volatile memory capable of maintaining the memory for 10 years or more, for example.
And is connected so that data can be input and output.

On the other hand, the temperature sensor 5 mounted in pressure contact with the container 2 changes its resistance value according to the temperature of the water in the container 2. Therefore, the DC voltage obtained by dividing the driving power supply voltage Vdd by the temperature sensor 5 and the resistor 6a connected in series changes in accordance with the liquid temperature. This voltage is input to the A / D converter 6b as a signal corresponding to the temperature of the liquid, converted into a digital value, and input to the microcomputer 8a. In addition, the voltage determined by the resistors 6c and 6d, the voltage determined by the resistors 6e and 6f, and the voltage determined by the resistors 6g and 6h are the temperature at the time of high temperature insulation (about 95 degrees C) and 85, respectively.
Temperature during heat retention (about 85 degrees C), temperature during heat retention 70 (about 7
The voltage corresponding to 0 degree C) is input to the A / D converter 6b.

When the power is restored, the microcomputer 8a calls whether the operating state before the power failure stored in the storage means 14 was boiling, keeping warm, or during the rest time, and during the rest time. If there is, the LED for the time set on the timer display means 10a is turned on and the heating start is waited for the stored time.
If it is in the boiling mode, the stored boiling mode is continued and the predetermined L of the boiling display means 10c is set.
Turn on the ED. When the temperature is kept warm, the temperature data from the temperature detecting means 6 keeps the temperature within the predetermined warm temperature range and turns on a predetermined LED of the warm display means 10b to lower the temperature to a predetermined temperature range or more. If so, it is boiled in the boiling mode called from the storage means 14, and then controlled to keep the temperature at the set temperature, and the LEDs corresponding thereto are turned on in the boiling mode display means 10c and the heat retention display means 10b.

When it is desired to change the heat retention temperature, the switch of the heat retention temperature setting means 11 is pressed to display the heat retention display means 1.
Change to the heat-retaining temperature indicated by the LED that lights up 0b. When it is desired to change the boiling mode, the boiling mode setting means 12
The switch is pressed to change to the boiling mode indicated by the lighted LED of the boiling mode display means 10c.

The operation when the power is turned on or when the power is restored from a power failure will be described below with reference to FIGS. 4, 5 and 6. FIG. 4 is a schematic flowchart showing the operation of one embodiment of the present invention, and FIGS. 5 and 6 are flowcharts showing details of step 1 and step 2 in FIG. 4, respectively. In step 100, the SNS signal of the power failure detection means 13 is checked to detect power recovery. When power is restored and the SNS signal becomes the "high" level, in step 101, the heat retention data from the storage means 14, the boiling mode data, the operating state of whether the operating state is the boiling mode or the warming,
If the rest time is set, the rest time until the start of heating is set. In step 102, it is checked whether or not the rest time is set, and if it is set, the process proceeds to step 103 to display the rest time and measure the time, and when the rest time ends, the setting is canceled and the process goes to step 107. Transition. If the pause time is not set in step 102, the process proceeds to step 104, and it is checked whether the operating state before the power failure is boiling or keeping heat. If it is boiling, step 105
Then, the operation and display in the boiling mode is started, and if the temperature is being kept warm, the process goes to step 106 to start the operation and display for the warming (refer to FIG. 5 for the above operation).

In the state where the heat retention or boiling is started, the process proceeds to step 107 and the rest time setting is always checked.
This is to cope with the possibility that the user will set the rest time again. When the switch of the timer setting means 9 is pressed, the process proceeds to step 108 to display the rest time and measure the time, heating is not started during that time, and when the rest time ends, the setting is canceled and the process proceeds to step 109. In step 109, it is checked whether the switch of the boiling mode setting means 12 is pressed. This is to cope with the possibility that the user sets the boiling mode again. If the switch of the boiling mode setting means 12 is pressed, the process proceeds to step 110 and the operation and display of the boiling mode is started. If the switch of the boiling mode setting means 12 is not pressed, the routine proceeds to step 111, where it is checked whether the heat retention temperature setting switch is pressed. This is to cope with the possibility that the user may set the heat retention temperature again. If the switch of the heat retention temperature setting means 11 is pressed, the process proceeds to step 112 to start the operation and display of the heat retention temperature, and if not pressed, the process proceeds to step 113.

With the above operation, the operation according to the set condition is started, and the process proceeds to step 113. At step 113, the process waits for several ms when these operations are started. During that time, the SNS signal is constantly checked in step 114, and if the input of the SNS signal is the "low" level, the power failure continues, so it is determined that there is a power failure, and the routine proceeds to step 115. If the SNS signal is not at the "low" level in step 114, the process returns to step 107 to continue the normal operation. In step 115, the display is turned off and the operation is stopped in response to the power failure, and the process proceeds to step 116, and the currently set boiling mode, heat retention temperature, current operating state (whether boiling or heat retention), and pause. The time is set, or if set, the rest time until the start of heating is stored in the non-volatile memory 14, respectively. Next, in step 117, the SNS signal is checked to observe the continuation of the power failure. If the SNS signal is not at "low" level, there is a possibility that power has been restored, and the process returns to step 100 to check the power restoration (refer to FIG. 6 for the above operation).

As described above, according to the embodiment of the present invention, the set operating conditions and operating states before the power failure are stored in the storage means, and when the power is restored, the stored contents are referred to to automatically store the information before the power failure. Since the operation is restored, there is no need to set the operation condition again when the power is restored, and the electric water heater is very convenient for the user.

Although a non-volatile memory is used as the storage means in this embodiment, it is a means for backing up the microcomputer with a capacitor, a primary battery, a secondary battery, etc. by using the memory in the microcomputer as the storage element. It goes without saying that it is good.

(Embodiment 2) An electric water heater according to a second embodiment of the present invention will be described below with reference to the drawings. The main constituent elements of this embodiment are the same as those of the first embodiment, and will be described with reference to FIGS. 1, 2, and 3. This embodiment differs from the first embodiment in that a part of the control operation of the microcomputer 8a in FIG. 2 and the capacity of the capacitor 8a are made sufficiently large to correspond to a long down time. is there. The operation of the present embodiment is shown in a schematic flow chart in the same way as in FIG. 4, and in the step 1, the same operation as in the first embodiment shown in FIG. 5 is performed. However, the operation of step 2 is partially different from that of the first embodiment, and the details of step 2 are shown in the flowchart of FIG. In addition,
In FIG. 6 and FIG. 7, the same operation number is given to the same operation step and the description thereof is omitted.

In FIG. 7, the operation of this embodiment differs from that of the first embodiment in the operation of the added step 118. In this embodiment, step 11 is performed as in the first embodiment.
At 7 it is checked whether the SNS signal is at the "low" level to check the continuation of the power outage. If the power outage continues, the process proceeds to step 118, and if the pause time is set, the power outage also occurs. The elapsed time of the power outage is subtracted from the rest time stored at the time of the power outage by measuring the elapsed time. Therefore, when the power is restored, the time during the power failure is corrected from the stored rest time, and heating is started after the desired rest time when set. This measure is effective when the power failure is long.

When the power failure lasts for a long time, the DC drive power source must be supplied in order for the control means such as the microcomputer 8a to operate normally during that time. Therefore, the capacity of the capacitor 8e inserted in the DC drive power source is increased, and for example, a large-capacity electrolytic capacitor is used so that it can be set to handle power failure for several hours or several tens of hours.

As described above, according to the second embodiment of the present invention, the rest time set before the power failure is counted down during the power failure to correct the power failure time, so that the rest time is set correctly after the initially set rest time. The heating can start. Of course, it goes without saying that it is not necessary to reset the operating conditions when the power is restored.

[0032]

As is apparent from the above embodiments, the present invention comprises a container for containing a liquid, a heating source for heating the liquid, and a temperature detecting means for detecting the temperature of the liquid,
Operation condition setting means for setting conditions such as boiling and heat retention of the liquid and a rest time until the start of heating, and a power failure detecting means for detecting a significant voltage drop or power failure of the power supply as a power failure for a predetermined time or more. And storage means,
And a control means for controlling heating start, boiling, and heat retention operation of the liquid in accordance with the operating conditions, and the control means, when the power failure is detected by the power failure detection means, the operation set before the power failure. By storing the conditions and the operating state before the power failure in the storage means and controlling the heating and warming operations by referring to the operating conditions and the operating status stored in the storage means at the time of power recovery, the power recovery When the power is turned on or when the power is turned on again, you can automatically set the heat retention temperature, the mode at the time of boiling, and the rest time without pressing the setting switch many times, and the user can set the setting switch many times. It is an electric water heater that is easy to use and does not require pressing and resetting.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional block diagram showing a configuration of an electric water heater according to first and second embodiments of the present invention.

FIG. 2 is a circuit block diagram showing an electrical configuration of the electric water heater of the first and second embodiments of the present invention.

FIG. 3 is a waveform diagram showing a waveform of a power failure detecting means in the electric water heater of the first and second embodiments of the present invention (a) is a waveform diagram showing an AC power supply waveform, and (b) is a waveform of an SNS signal. Waveform diagram shown (C) is a waveform diagram showing the power failure detection waveform of the microcomputer.

FIG. 4 is a flowchart showing a schematic operation of the electric water heater according to the first and second embodiments of the present invention.

5 is a flowchart showing in detail the operation of the electric water heater of the first and second embodiments of step 1 shown in FIG.

6 is a flowchart showing in detail the operation of the electric water heater of the first embodiment of step 2 shown in FIG.

FIG. 7 is a flowchart showing in detail the operation of the electric water heater of the second embodiment of step 2 shown in FIG.

FIG. 8 is a partial cross-sectional block diagram showing the configuration of a conventional electric water heater.

[Explanation of symbols]

 2 container 4 heating source 5 temperature sensor (temperature detecting means) 6 temperature detecting means 8 control means 9 timer setting means (condition setting means) 11 heat retention temperature setting means (condition setting means) 12 boiling mode setting means (condition setting means) 13 Power failure detection means 14 Storage means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hironobu Tanaka 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (5)

[Claims] 1. A container for containing a liquid, a heating source for heating the liquid, a temperature detecting means for detecting the temperature of the liquid, a condition for boiling and keeping heat of the liquid, and a dwell time before starting heating. Etc., operating condition setting means for setting, a power failure detecting means for detecting a significant voltage drop or power failure of the power source as a power failure for a predetermined time or more, a storage means, and a heating start, boiling and heat retention of the liquid. And a control means for controlling the operation in accordance with the operating conditions, the control means, when the power failure is detected by the power failure detection means, the operating conditions set before the power failure and the operating state before the power failure. An electric water heater which is stored in the storage means and which controls heating and heat retention operations by referring to the operating conditions and operating states stored in the storage means when power is restored. 2. The operating condition setting means sets the heat retention temperature of the liquid to 1
Equipped with heat retention temperature setting means that can set more than one type, the control means compares the detected liquid temperature with the heat retention temperature set value stored in the storage means when the power is restored from the power failure, and the temperature difference from the set value is within the predetermined value. If so, the warming operation is performed so as to reach the set value, and if the temperature difference is equal to or more than the predetermined value, it is boiled and then controlled to keep the temperature at the set value. 3. The operating condition setting means sets the heat retention temperature of the liquid to 1
The heat retention temperature setting means capable of setting more than one kind and the boiling mode setting means capable of setting one or more kinds of modes for boiling the liquid are provided, and the control means stores the detected liquid temperature in the storage means when the power is restored from the power failure. If the temperature difference with the set value is within a predetermined value, the heat retaining operation is performed, and if the temperature difference is equal to or more than the predetermined value, boiling is performed according to the boiling mode stored in the storage means. The electric water heater according to claim 1, wherein the electric water heater is controlled so as to keep the temperature at the set value. 4. The operation condition setting means is provided with a timer setting means capable of setting one or more kinds of pause time until the liquid starts to be heated, and the control means refers to the pause time stored in the storage means when the power is restored from a power failure. The electric water heater according to claim 1, wherein the electric water heater is controlled so as to start heating. 5. The electric water heater according to claim 4, wherein the control means controls so as to start heating by correcting the time during power failure to the rest time stored in the storage means when power is restored.