JPH0833235B2 - Electric water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an improvement of a control device for an electric water heater.

[Prior Art] FIG. 20 is a block diagram showing a configuration of a conventional electric water heater,
FIG. 21 is an electric circuit diagram of the main part. In FIG. 20, reference numeral 1 denotes a hot water storage tank, in which a lower heating element 2 is arranged in the lower part and an upper heating element 3 is arranged in the middle part. 4 is attached to the side wall of the hot water storage tank 1, lower water temperature measuring means for measuring the feed water temperature and boiling temperature, 5 upper temperature measuring means for measuring the boiling temperature by the heating element 3, 6 sets the boiling temperature The hot water temperature setting means 7 is an operation means for calculating the net energization time and the energization start time based on the information of the lower hot water temperature measuring means 4 and the hot water temperature setting means 6. Further, 8 is a midnight power detecting means for detecting the presence or absence of supply of midnight power, and 9 is an ON / OFF switch for the lower heating element 2 based on the information of the computing means 7, the midnight power detecting means 8 and the lower hot water temperature measuring means 4. It is a lower heating element control means for controlling. Further, 10 is a reheating setting means for setting energization of the upper heating element 3, and 11 is an upper heating element for controlling ON / OFF of the upper heating element 3 based on information of the additional heating setting means 10 and the upper hot water temperature measuring means 5. It is a control means.

Next, in FIG. 21, reference numeral 12 is a microcomputer, which comprises a CPU 13, a memory 14, an input circuit 15, an output circuit 16, an A / D converter 17 and an analog multiplexer 18.

Reference numeral 19 denotes a circuit that constitutes the lower heating element control means 9, which is composed of resistors 20, 21, transistors 22, relays 23, 24, and diodes 25, 26.
The coil 23 is connected between the positive terminal + V and the ground terminal via the transistor 22, and the base of the transistor 22 is connected to the output circuit 16 of the microcomputer 12 via the resistor 20. The normally open contact is the positive terminal + V1 and the relay.
Connected to the ground terminal via a coil of 24, relay 23,
Diodes 25 and 26 are connected to both ends of the coil of 24, respectively. The heating element 2 is connected in series between the normally open contact of the relay 24 and the midnight power supply 27.

Further, 28 is a circuit showing the configuration of the heating element control means 11, which includes resistors 29, 30, a transistor 31, a relay 32 and a diode 33.
The coil of the relay 32 is connected between the positive terminal + V and the ground terminal via the transistor 31, and the base of the transistor 31 is connected to the output circuit 16 of the microcomputer 12. The heating element 3 is connected in series between the normally open contact of the relay 32 and the power source 34 for the electric lamp for the daytime.

The temperature measuring means 4 and 5 are thermistors and the hot water temperature setting means 6 is a variable resistor. The resistance 35 is connected in series with the lower hot water temperature measuring means 4, and this series circuit is connected between the positive terminal + V and the ground terminal.
The connecting portion between the lower hot water temperature measuring means 4 and the lower hot water temperature measuring means 4 is connected to the analog multiplexer 18. The resistor 36 is connected in series with the upper hot water temperature measuring means 5, and the series circuit is connected between the positive terminal + V and the ground terminal, and the connecting portion between the resistor 36 and the upper hot water temperature measuring means 5 is an analog multiplexer 18. It is connected to the. The resistor 37 is connected in series with the hot water temperature setting means 6,
This series circuit is connected between the positive terminal + V and the ground terminal, and the connection between the resistor 37 and the hot water temperature setting means 6 is connected to the analog multiplexer 18 of the microcomputer 12.

The circuit 38 constituting the midnight power detection means 8 includes resistors 39 and 4
0, a diode 41, and a phototransistor 42. The light emitting side of the phototransistor 42 is connected in series to the power supply 27 via the resistor 39, and the diodes 41 are connected in parallel at both ends thereof. On the other hand, one end of the phototransistor 42 on the light receiving side is connected to the positive electrode terminal + V via the resistor 40, and the other end is connected to the ground terminal. The connecting portion between the light receiving side and the resistor 40 is an input circuit of the microcomputer 12. Connected to 15. The resistor 43 is connected in series to the reheating setting means composed of the switch 10, the positive electrode terminal + V and the ground terminal, and the connecting portion between the resistance 43 and the reheating setting means 10 is the microcomputer 12.
Connected to the input circuit 15 of.

Next, the operation of the conventional device configured as described above will be described with reference to the flowchart of FIG. This flow chart shows the control means for the heating elements 2 and 3 stored in the memory 14 of the microcomputer 12.

Simultaneously with the start, it is checked whether or not the midnight power is supplied (step 44). If the midnight power is supplied, a signal is input to the input circuit 15 of the microcomputer through the phototransistor 42 and the timer for counting elapsed time is started. (Step 45). Next, the lower hot water temperature measuring means 4 measures the feed water temperature Tw ° C (step 46), and the used hot water temperature T ° C is read (step 47). If the capacity of the heating element 2 is PKW, the net energization time H can be calculated by the following formula (step 48).

Where V: capacity of hot water storage tank 860: calorific value of 1 kwh 0.9: efficiency Next, based on the above data, CPU1 of microcomputer
The energization start time is calculated according to 3 (step 49). In order to efficiently use the late-night power, which has a low power rate, it is desirable that the boiling has just been completed at the end of the late-night power supply time period. Therefore, the power supply time from midnight to 8
If the time is 8 hours, the energization start time Hp becomes Hp = 8−H. That is, if the net energization time H is 4 hours, the energization start time Hp is 4:00 am.

Then, it is determined whether the elapsed time by the timer has reached the energization start time (step 50), and when the energization start time is reached, the output signal from the output circuit 16 of the microcomputer 12 is applied to the transistor 22 of the heating element control circuit 19. ,relay
23 and 24 are turned on to open the power supply circuit, and power supply to the heating element 2 is started (step 51).

Next, the lower hot water temperature measuring means 4 measures the hot water temperature Tm1 ° C in the hot water storage tank 1 (step 52), then compares the boiling temperature T ° C with the hot water temperature Tm1 ° C (step 53), and the hot water temperature Tm1 is boiled. When the raised temperature T is reached, the output signal from the output circuit 16 is cut off, the relay 24 is opened and the power supply circuit to the heating element 2 is turned off (step 54), and the control is terminated.

Also, there is no power supply at midnight (NO in step 50)
If the switch is ON, the upper hot water temperature measuring means 5 measures the upper hot water temperature Tm2 in the hot water storage tank (step 5).
6) Compare Tm2 with boiling temperature T (step 57) Tm
When 2 is smaller than T, the upper heating element 3 is turned on (step 58), and when Tm2 is larger than T, the upper heating element 3 is turned off.
(Step 59). Next, the presence / absence of the midnight power source is determined (step 60), and if the midnight power is supplied, the upper heating element 3
Power is turned off (step 61) and the boiling by the daytime power supply is terminated.

A conventional electric water heater is constructed and operates as described above.

[Problems to be Solved by the Invention] However, the above-described conventional electric water heater has the following problems in use, and therefore does not necessarily conform to today's fast-paced daily life rhythm, resulting in efficiency and usability problems. But I still have some problems.

(1) The lower heating element 2 is capable of boiling within the midnight power supply time zone, and the upper heating element 3 is limited to the daytime hours other than the above-mentioned time restrictions. .

(2) When the boiling operation by the upper heating element 3 starts, the heating element 3 repeats ON / OFF until the midnight power supply time period, so if you forget to do the boiling operation and have not stopped The ON / OFF of the upper heating element 3 may be repeated, resulting in unnecessary power consumption.

(3) If you forget to turn on the switch for starting reheating, such as when the amount of hot water used is large, the hot water becomes insufficient immediately and you cannot use it.

(4) Further, the control is complicated because a method of moving the energization time of the lower heating element 2 to the latter half of the midnight power supply time zone by using the calculating means 7 is complicated.

The present invention has been made to solve the above problems of the conventional device, and simplifies the control by omitting the calculating means in the conventional device, and can be boiled by a heating element at any time, Also, the electric water heater which is configured to automatically start boiling when the amount of remaining hot water falls below a predetermined amount will be provided so that the operation is required again for the next boiling It is a thing.

[Means for Solving the Problems] An electric water heater according to a first aspect of the invention is installed in a hot water storage tank, a lower heating element installed in a lower part of the hot water storage tank, and an upper portion of the hot water storage tank than the lower heating element. Upper heating element, lower hot water temperature measuring means for measuring the water supply temperature to the hot water storage tank and lower hot water temperature of the hot water storage tank, upper hot water temperature measuring means for measuring the hot water temperature of the upper hot water storage tank, and boiling water Boiling setting means for setting the amount of hot water used related to the temperature or boiling water temperature, and energization time zone setting means for setting the energizable time zone for both or one of the lower heating element and the upper heating element, A heating element control means for controlling energization to the lower heating element and the upper heating element and an additional heating setting means for setting additional heating are provided. Then, the heating element control means controls the lower heating element and the upper heating element on the basis of the information from the lower hot water temperature measuring means, the upper hot water temperature measuring means, the boiling setting means, the additional heating setting means and the energization time zone setting means. Control the energization of
The upper heating element is energized only once in a time zone other than the energizable time zone for the lower heating element set by the energization time zone setting means, and if it is reset, the upper heating element can be repeatedly energized.

An electric water heater according to a second aspect of the present invention includes a hot water storage tank, a lower heating element installed in a lower portion of the hot water storage tank, an upper heating element installed in an upper portion of the hot water storage tank than the lower heating element, and a hot water storage tank. Lower hot water temperature measuring means for measuring the water supply temperature of the hot water and the lower hot water temperature of the hot water storage tank, upper hot water temperature measuring means for measuring the hot water temperature of the upper hot water storage tank, and residual hot water amount detection for detecting the amount of residual hot water in the hot water storage tank Means, boiling temperature setting means for setting the boiling water temperature or the amount of hot water used related to the boiling water temperature, and energization for setting the energizable time zone for the lower heating element and / or the upper heating element. Time zone setting means, heating element control means for controlling energization to the lower heating element and the upper heating element, and setting for automatically starting reheating by the upper heating element according to the information of the remaining hot water amount detecting means With automatic reheating setting means It is provided. Then, the heating element control means, based on the information from the lower hot water temperature measuring means, the residual hot water amount detecting means, the upper hot water temperature measuring means, the boiling setting means, the automatic reheating setting means and the energization time zone setting means, The energization to the body and the upper heating element is controlled, and the upper heating element is energized only once in the time zone other than the energizable time zone set to the lower heating element by the energization time zone setting means. For example, electricity can be repeatedly applied to the upper heating element.

In the third invention, the heating element control means of the first invention or the second invention comprises a lower heating element control means for controlling energization to the lower heating element and a heating element for controlling energization to the upper heating element. And control means.

[Operation] In the first invention, the lower hot water temperature measuring means measures a water supply temperature to the hot water storage tank and a hot water temperature at a lower portion of the hot water storage tank,
The upper hot water temperature measuring means measures the hot water temperature above the hot water storage tank,
The hot water temperature is monitored by these hot water temperature measuring means. Also,
The boiling setting means sets an arbitrary hot water temperature or hot water amount, and the energization time zone setting means sets the energization time zone of the lower heating element and / or the upper heating element. Further, the heating element control means sets the energization time zone of the lower heating element and / or the upper heating element set by the energization time zone setting means, and the hot water temperature measured by the lower hot water temperature measuring means and the upper hot water temperature measuring means, respectively. Based on this, the energization of the lower heating element and the upper heating element is controlled. Further, the additional heating setting means sets additional heating. Further, in the time zone other than the time zone in which the lower heating element can be energized, which is set by the energization time zone setting means,
The upper heating element is energized only once, but if reset, the upper heating element can be energized repeatedly. Therefore, the energization time zone setting means can arbitrarily set the energization time zone to the heating element regardless of the midnight power supply time zone, and by providing the reheating setting means, the boiling is forcibly performed at any time. be able to. Therefore, when the amount of hot water used is large at a ceremonial occasion or the like, it is possible to forcibly boil water, and it is also possible to select the hot water according to the usage status of the hot water.

In the second invention, the lower hot water temperature measuring means measures a water supply temperature to the hot water storage tank and a hot water temperature at a lower portion of the hot water storage tank,
The upper hot water temperature measuring means measures the hot water temperature above the hot water storage tank,
The hot water temperature is monitored by these hot water temperature measuring means. Also,
The remaining hot water amount detecting means detects the remaining hot water amount in the hot water storage tank, the boiling water setting means sets an arbitrary hot water temperature or hot water amount, and the energization time zone setting means sets the energization time zone of the lower heating element and / or the upper heating element. Is set. Further, the heating element control means sets the energization time zone of the lower heating element and / or the upper heating element set by the energization time zone setting means, and the hot water temperature measured by the lower hot water temperature measuring means and the upper hot water temperature measuring means, respectively. Based on this, the energization of the lower heating element and the upper heating element is controlled. The automatic reheating setting means controls the energization of the upper heating element through the heating element control means in accordance with the information of the remaining hot water amount detecting means to heat the water supply and automatically start reheating. Further, in the time period other than the time period in which the lower heating element can be energized, which is set by the energization time period setting means, the upper heating element is energized only once, but if it is reset, the upper heating element is energized. Can be repeated.

In the third invention, the lower heating element control means controls energization to the lower heating element, and the upper heating element control controls energization to the upper heating element. By thus separating the control systems for the lower heating element and the upper heating element, the control system is simplified.

[Embodiment of the Invention] FIG. 1 is a block diagram of an electric water heater showing an embodiment of the present invention. In the figure, 1 to 9 indicate the same or equivalent parts as the conventional device, and 69 indicates a lower heating element. A heating element control means composed of a control means and an upper heating element control means, 70 has a timepiece function, and an energization time for which the energization time zone of both the lower heating element and / or the upper heating element can be set. A band setting means 74 is an upper heating element control means for controlling the upper heating element 3 according to the information of the upper hot water temperature measuring means 5 and the energization time period setting means 70.

FIG. 2 is an electric circuit diagram of the above embodiment, in which 75 is a display circuit for amplifying an output signal from the output circuit 16 of the microcomputer 12, and 76 is an output signal of the display circuit 75 and the output circuit 16. A display means for displaying based on the output signal. Reference numerals 80, 81, and 82 are resistors, which are connected in series to the power supply + V and the ground terminal with the energization time period setting means 70 which is composed of switches, and the connection between each switch and the resistor is connected to the input circuit 15 of the microcomputer 12. .

FIG. 3 is a front view showing the operation section and the display section of the present embodiment. 83, 84 and 85 are energization time setting means composed of switches, 83 is a changeover switch, 84 is time, 85 is minute. It is a switch for setting. Also, 86, 87 and 88 are lamps showing the current time, the energization start time and the energization stop time, respectively.
89 is an indicator lamp for displaying the time.

In the figure, when the power is turned on, the display unit lights the current time lamp 86, and the display lamp 89 indicates 00:00. When the display changeover switch 83 is operated, the current time lamp 86 is turned off and the energization start time 87 is turned on. When the changeover switch 83 is further operated, the energization start time 87 is turned off and the energization stop time 88 is turned on. When the selector switch 83 is further operated, the power supply stop time 88
Turns off, the current time 86 turns on and returns to the original state. In setting the energization start time and energization stop time, the energization start time lamp 87 for the former is turned on, and the energization stop time lamp 88 for the latter is turned on, and the time setting switch 84 and the minute setting switch 85 are operated. Do it.

FIG. 4 is a flow chart showing the heating element control stored in the memory 14 of the microcomputer. The same or corresponding steps as those in the conventional example are designated by the same reference numerals, and the description thereof will be omitted.

First, turn on the power and at the same time set the boiling target temperature to
The temperature is set to 90 ° C. (step 98), the current time is set (step 90), the energization start time is set (step 91), and the energization stop time is set (step 92). Then the above steps
It is judged that the energization start time set by 91 is reached (step 93), and if the time is reached, the lower heating element 2 is energized (step 51) to heat the water supply and measure the lower hot water temperature Tm1. (Step 52), the hot water temperature Tm1 is compared with the boiling temperature T (Step 53), and when Tm1 reaches the boiling temperature T, the lower heating element 2 is turned off (Step 54).

In step 93, when the energization start time has not been reached, the upper hot water temperature Tm2 is measured (step 56) and the hot water temperature Tm2 is measured.
Is compared with the boiling temperature T (step 57). If Tm2 has not reached the boiling temperature T, the upper heating element 3 is energized (step 58) to heat the feed water, and if it is reached, the upper heating element 3 is turned off. (Step 59). Next, if the energization start time has not come, the process returns to step 56 and the upper heating element 3
Repeats ON / OFF, and turns off the upper heating element 3 if reached
(Step 61) Complete the reheating.

In the present embodiment, the energization start and stop times are set at arbitrary times regardless of the midnight power supply time zone, the lower heating element 2 is energized to heat the feed water, and if the time is outside the energization time zone. ON / OFF of the upper heating element will be repeated.

FIG. 5 is a block diagram of another embodiment in which the boiling setting means 6A is added to the embodiment shown in FIG. 1, and FIG. 6 is an electric circuit diagram thereof. The boiling setting means 6A is composed of a variable resistor. It will be.

FIG. 7 is a flow chart showing the operation of the embodiment shown in FIG.

First, when the power is turned on, the current time is set (step 90), the energization start time is set (step 91), and the energization stop time is set (step 92). Next, it is determined whether the energization start time set in step 91 has been reached (step 93). If the time has been reached, the hot water temperature T used is read (step 47) and the lower heating element 2 is energized (step). 51) Heat the feed water, measure the lower hot water temperature Tm1 (step 52), compare the hot water temperature Tm1 with the boiling temperature T (step 53), and when Tm1 reaches the boiling temperature T, lower the heating element 2 Turn it off (step 54). In step 93, when the energization start time has not been reached, the operation is the same as that of the embodiment shown in FIG.

In this embodiment, it is possible to set the hot water temperature to be used, set the energization start and stop times at arbitrary times regardless of the midnight power supply time zone, energize the lower heating element 2 to heat the water supply, and energize. If it is outside the time zone, the upper heating element will be repeatedly turned on and off.

FIG. 8 shows the reheating setting means 73 in the embodiment of FIG.
7 is a block diagram of another embodiment in which the upper hot water temperature measuring means 5, the energization time zone setting means 70, and the reheating setting means are shown.
The upper heating element control means controls the upper heating element 3 according to the information of 73.

FIG. 9 is an electric circuit diagram thereof, and 79 is a resistor, which is connected in series with the reheating setting means 73 composed of a switch, to the power source + V and the ground terminal, and the switch and the resistor are connected to the input circuit 15 of the microcomputer 12. It is connected.

FIG. 10 is a flow chart showing the operation of the embodiment shown in FIG.

First, turn on the power and set the current time at the same time (step 9
0), then the energization start time is set (step 91), and the energization stop time is set (step 92). Next, it is determined whether the energization start time set in step 91 has been reached (step 93). If the time has been reached, the hot water temperature T used is read (step 47) and the lower heating element 2 is energized (step). 51) Heat the feed water, measure the lower hot water temperature Tm1 (step 52), compare the hot water temperature Tm1 with the boiling temperature T (step 53), and when Tm1 reaches the boiling temperature T, lower the heating element 2 Turn it off (step 54). In step 93, when the energization start time has not been reached, it is determined whether or not the reheating setting means is set (step 94), and if set, the upper hot water temperature Tm2 is measured (step 56), and the hot water temperature is set. Tm2
Is compared with the boiling temperature T (step 57). If Tm2 has not reached the boiling temperature T, the upper heating element 3 is energized (step 58) to heat the feed water, and if it is reached, the upper heating element 3 is turned off. (Step 59). Next, if the energization start time has not come, the process returns to step 56 and the upper heating element 3
Repeat ON / OFF, and if reached, turn off the upper heating element (step 61) to complete reheating.

In this embodiment, the hot water temperature to be used can be set, and the energization start and stop times can be set at arbitrary times irrespective of the midnight power supply time zone to energize the lower heating element 2 to heat the water supply. it can. When the hot water is used more frequently, the upper heating element 3 can be forcibly energized and reheated by operating the hot water at any time.

Further, in this embodiment, if the reheating setting means is set at a time outside the energization time zone, energization of the upper heating element is turned on / off.
The flow chart shown in FIG. 11 is configured such that when the hot water temperature Tm2 reaches the boiling temperature T, the energization of the heating element is stopped and the boiling is limited to once. Is.

Whether or not reheating is repeated or limited to once should be decided according to the usage conditions of hot water. When the frequency of using hot water is low, reheating should be done only once and unnecessary power consumption should be avoided. However, when hot water is frequently used and high-temperature hot water is required, reheating can be repeated to keep the hot water at a high temperature.

FIG. 12 shows a residual hot water amount detecting means 71 in the embodiment of FIG.
FIG. 19 is a block diagram of another embodiment in which an automatic reheating setting means 72 is added, and 74 is an upper heating element according to information of the upper hot water temperature measuring means 5, the energization time zone setting means 70, and the automatic reheating setting means 72. 3 is an upper heating element control means for controlling 3.

FIG. 13 is an electric circuit diagram thereof, and 77 and 78 are resistors, which are respectively connected to the power supply + V and the ground terminal in series with the residual hot water amount detecting means 71 consisting of a thermistor and the automatic reheating setting means 72 consisting of a switch, The connection between the switch and the resistor is connected to the input circuit 15 of the microcomputer 12.

FIG. 14 is a flow chart showing the operation of the embodiment shown in FIG.

First, turn on the power and set the current time at the same time (step 9
0), then the energization start time is set (step 91), and the energization stop time is set (step 92). Next, it is determined whether the energization start time set in step 91 has been reached (step 93). If the time has been reached, the hot water temperature T is read (step 47) and the lower heating element 2 is energized (step 47). 51) Heat the feed water, measure the lower hot water temperature Tm1 (step 52), compare the hot water temperature Tm1 with the boiling temperature T (step 53), and when Tm1 reaches the boiling temperature T, lower the heating element 2 Turn it off (step 54). In step 93, if the energization start time has not been reached, it is determined whether or not the automatic reheating setting means is set (step 94), and if set, the remaining hot water amount detecting means 71 detects the remaining hot water amount ( Step 95), it is detected whether the amount of remaining hot water is less than a predetermined amount (step 96), and if the amount of remaining hot water is less than the predetermined amount, the upper hot water temperature Tm2 is measured (step 56), and the hot water temperature Tm2 is boiled. Compare with the raising temperature T (step 57), Tm2 is the boiling temperature T
If it has not reached the upper limit, the upper heating element 3 is energized (step 5
8) Heat the water supply, and if it reaches, turn off the upper heating element 3 (step 59). Next, if the energization start time has not been reached, the process returns to step 56 and the ON / OFF of the upper heating element 3 is repeated. If it has reached, the upper heating element is turned OFF (step 61) to complete the reheating.

In this embodiment, the hot water temperature to be used can be set, and the energization start and stop times can be set at arbitrary times irrespective of the midnight power supply time zone to energize the lower heating element 2 to heat the water supply. it can. Further, the amount of remaining hot water can be detected, and if the amount of remaining hot water is equal to or less than a predetermined amount, the upper heating element 3 can be automatically energized to be reheated.

Further, in this embodiment, the automatic reheating setting means is set at a time outside the energization time zone, and if the amount of remaining hot water is equal to or less than a predetermined amount, energization of the upper heating element will repeat ON / OFF, The flow chart shown in FIG. 15 is configured such that when the temperature Tm2 reaches the boiling temperature T, the power supply to the heating element is stopped, and the boiling is limited to once.

By limiting the reheating to only once, it is possible to avoid unnecessary power consumption when the hot water is used infrequently.

FIG. 16 is a block diagram of another embodiment in which the reheating setting means is added to the embodiment of FIG. 12, and 74 is the upper hot water temperature measuring means 5, the energization time zone setting means 70, the reheating setting means 7
3. Upper heating element control means for controlling the upper heating element 3 according to the information of the automatic reheating setting means 72.

FIG. 17 is an electric circuit diagram thereof, and FIG. 18 is a flowchart showing an operation in which reheating is repeated at times outside the energization time zone in this embodiment.

FIG. 19 is a flow chart showing an operation in which reheating is performed only once in a time outside the energization time zone in this embodiment.

In this embodiment, the hot water temperature to be used can be set, and the energization start and stop times can be set at arbitrary times irrespective of the midnight power supply time zone to energize the lower heating element 2 to heat the water supply. it can. Further, by providing the reheating setting means in addition to the automatic reheating setting means, the remaining hot water amount can be detected, and if the remaining hot water amount is less than or equal to a predetermined amount, the upper heating element 3 can be automatically energized for reheating. If the hot water is used frequently, the hot water can be forcibly reheated at any time, and the reheating can be repeated or only once depending on the use conditions.

In this embodiment, the electric water heater is provided with various devices and is provided with various functions to make the electric water heater extremely efficient and easy to use.

[Effects of the Invention] The electric water heater according to the first invention is a boiling setting means,
It is equipped with an energization time zone setting means and a reheating setting means, and can set the boiling water temperature or the amount of hot water so that the heating element can be energized at any time, so the hot water can be adjusted according to the rhythm of daily life. Since it is now possible to use the hot water and to reheat it at any time, there is no fear of running out of hot water even when consuming a large amount of hot water, such as during a ceremonial occasion. Further, since the heating element for reheating is energized only once, it is possible to prevent waste of electric power. Also, if you reset it, you can repeat the energization, so you can select it according to the usage situation of the hot water, which is convenient.
This is the emergence of a water heater that is extremely easy to use.

An electric water heater according to a second aspect of the invention is a boiling setting means,
Equipped with energization time zone setting means, remaining hot water amount detecting means and automatic reheating setting means, it is possible to set boiling water temperature or hot water amount,
Since the heating element can be energized at any time, you can use hot water according to the rhythm of your daily life, and automatically when the amount of hot water in the hot water storage tank falls below a predetermined amount. Since it is configured to energize the heating element to start reheating, there is no danger of running out of hot water in normal times even if you forget to reheat. Further, since the heating element for reheating is energized only once, it is possible to prevent waste of electric power. Also, it is possible to repeat energization by resetting, so you can select according to the usage situation of hot water,
It is convenient.

In the electric water heater according to the third aspect of the present invention, the control system can be simplified by separating the control system of the lower heating element and the upper heating element.

[Brief description of drawings]

FIG. 1 is a block diagram of an electric water heater which is an embodiment of the present invention, FIG. 2 is an electric circuit diagram thereof, FIG. 3 is a front view of a display portion and an operating portion, FIG. FIG. 5 is a block diagram of another embodiment, FIG. 6 is an electric circuit diagram thereof, FIG. 7 is an operation flowchart, FIG. 8 is a block diagram of another embodiment, FIG. 9 is an electric circuit diagram thereof, and FIG. 10 and 11 are operation flowcharts, FIG. 12 is a block diagram of another embodiment, FIG. 13 is an electric circuit diagram thereof, FIGS. 14 and 15 are operation flowcharts, and FIG. 16 is another. FIG. 17 is a block diagram of an embodiment, FIG. 17 is an electric circuit diagram thereof, FIGS. 18 and 19 are operation flowcharts, FIG. 20 is a block diagram of a conventional electric water heater, and FIG. 21 is an electric circuit diagram thereof. FIG. 22 is a flowchart of the operation. In the figure, 1 is a hot water storage tank, 2 is a lower heating element, 3 is an upper heating element, 4 is a lower hot water temperature measuring means, 5 is an upper hot water temperature measuring means, and 6
Is a hot water temperature setting means, 6A is a boiling temperature setting means, 9 is a lower heating element control means, 69 is a heating element control means, 70 is an energization time zone setting means, 71 is a residual hot water amount detecting means, and 72 is an automatic reheating setting means. , 73 is a reheating setting means, and 74 is an upper heating element control means. The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (3)

[Claims] 1. A hot water storage tank, a lower heating element installed below the hot water storage tank, an upper heating element installed above the hot water storage tank above the lower heating element, and water supply to the hot water storage tank. Lower hot water temperature measuring means for measuring temperature and hot water temperature at the lower part of the hot water storage tank, upper hot water temperature measuring means for measuring hot water temperature at the upper part of the hot water storage tank, and boiling water temperature or use related to boiling water temperature The boiling setting means for setting the amount of hot water, the energization time zone setting means for setting the energizable time zone for the lower heating element and / or the upper heating element, and the lower heating element and the upper heating element The heating element control means for controlling the energization of the heating element and the additional heating setting means for setting the additional heating, and the heating element control means includes the lower hot water temperature measuring means, the upper hot water temperature measuring means, the boiling setting means, Fire setting means and Based on the information from the energization time zone setting means, the energization to the lower heating element and the upper heating element is controlled, and the time zone other than the energizable time zone for the lower heating element set by the energization time zone setting means. The electric water heater is characterized in that the above-mentioned upper heating element is energized only once, and if it is reset, the above-mentioned upper heating element can be repeatedly energized. 2. A hot water storage tank, a lower heating element installed below the hot water storage tank, an upper heating element installed above the hot water storage tank above the lower heating element, and water supply to the hot water storage tank. Lower hot water temperature measuring means for measuring temperature and lower hot water temperature of the hot water storage tank, upper hot water temperature measuring means for measuring hot water temperature of the upper hot water storage tank, and residual hot water amount detection for detecting the residual hot water amount in the hot water storage tank Means, boiling water temperature or boiling water setting means for setting the amount of hot water used related to the boiling water temperature, and the energizable time zone is set for the lower heating element and / or the upper heating element. Energization time zone setting means, heating element control means for controlling the energization of the lower heating element and the upper heating element, and automatically starting reheating by the upper heating element according to the information of the remaining hot water amount detection means. Set to The heating element control means comprises a lower hot water temperature measuring means, a residual hot water amount detecting means, an upper hot water temperature measuring means, a boiling setting means, an automatic additional heating setting means and an energization time zone setting means. Based on the information of the above, the energization to the lower heating element and the upper heating element is controlled, and the upper heating element is energized in a time period other than the energizable time period for the lower heating element set by the energization time period setting means. The electric water heater is characterized in that it is only once, and if it is reset, the above-mentioned upper heating element can be repeatedly energized. 3. The heating element control means comprises a lower heating element control means for controlling energization to a lower heating element and an upper heating element control means for controlling energization to an upper heating element. The electric water heater according to claim 1 or 2, which is characterized.