JPH0814424B2 - Hot water storage type electric water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Use of the Invention) The present invention relates to a hot water storage type electric water heater for boiling and storing hot water by electric power in a specific time zone with a low electricity rate, such as a midnight power supply time zone. It is also about improvement.

(Background of the Invention) A hot water storage type water heater is generally one that is supplied from a water supply port at the bottom of a tank and is supplied from the hot water supply port at the top of a tank. Many. With this type, it took a long time for the water in the entire tank up to the hot water supply port to reach a constant temperature. Especially, it is the longest time when all the water is in the tank.

Further, if hot water remains when the heater is energized, the water supplied from the water supply port and the residual hot water are agitated by heating, and the temperature of the residual hot water temporarily drops. Therefore, if hot water is used after the start of the midnight power energization period (for example, 23:00 to 7:00 the next morning) (for example, around 1:00 in the middle of the night), or if you want to use hot water urgently. Due to the above-mentioned reason, the hot water cannot be used due to the phenomenon of "out of water", which causes trouble to the user.

As a solution to this drawback, a heater is additionally installed near the hot water supply port on the upper part of the tank, and immediately after the midnight power energizing time, the upper heater is preferentially energized to boil the hot water in the upper part of the tank, Stop energizing the upper heater,
Japanese Patent Application Laid-Open No. 57-166443 proposes a method in which power is supplied to the lower heater so that the entire tank is heated to a high temperature. According to this two-heater system, the required hot water amount can be secured first even if the remaining hot water amount is small.

On the other hand, the applicant of the present application apportions the non-energization time within a specific time zone such as the midnight power energization time zone into the travel time distributed before the power distribution time and the margin time allocated after the power distribution time. , The start of energization is delayed from the beginning of the specific time zone by the moving time, the electric power demand by the electric water heater is moved toward the center of the specific time zone where the total electric power demand is the minimum, and the energizing time In the previous application, we proposed a hot water storage type electric water heater that can be extended.

If such a two-heater system is adopted in such a moving time type hot water storage type electric water heater, the upper heater can be immediately energized at the start of the midnight electric power supply time zone, and the electric demand by the electric water heater can be supplied by the late night electric power supply. There is a problem that moving it toward the center of the time zone is a contradiction.

(Object of the Invention) The object of the present invention is to solve the above-mentioned problems, to promptly secure the required amount of hot water for the time being, and to contribute to the averaging of the total electric power demand for the electric power company at the same time. It is to provide a hot water storage type electric water heater that can do.

(Characteristics of the Invention) In order to achieve the above object, the present invention provides non-energization within the specific time zone when the total energization time of the upper heater and the lower heater is expected to be shorter than the specific time zone. The time is proportionally divided into a moving time to be distributed before the total energizing time and a margin time to be allocated after the total energizing time, and when the amount of remaining hot water is larger than a predetermined amount, the upper heater and The moving time is taken before energizing the lower heater, and when the amount of remaining hot water is smaller than a predetermined amount, a calculating means for providing the moving time is provided between energizing the upper heater and energizing the lower heater. Therefore, when the amount of remaining hot water is less than the predetermined amount, the upper heater is energized immediately at the start of the specific time zone to focus on securing the amount of hot water. When the start of energization is specified The feature is that the power demand shift is emphasized by delaying the travel time from the start of the interzone.

(Embodiment of the Invention) FIG. 1 shows an embodiment of the present invention. As shown in FIG. 2, the temperature sensor 1, the lower temperature sensor 2a, the middle temperature sensor 2b, and the upper temperature sensor 2c using a thermistor or the like are attached from the bottom to the top of the outer wall surface of the tank 3. The temperature sensor 1 is adhered to the outer wall surface of the tank 3 near the water supply port 4, and is used for both water temperature detection and boiling temperature detection. The temperature sensors 2a and 2b are for detecting the amount of remaining hot water, and the temperature sensor 2c is also used for detecting the amount of remaining hot water and the boiling temperature. A lower heater 5 is installed near the water supply port 4, and an upper heater 7 is installed near the hot water supply port 6 located above the tank 3. The information from the temperature sensors 1, 2a to 2c is converted into a digital value by the A / D converter 8 and sent to the calculating means 9 such as a microprocessor. The time zone detecting means 10 is
For example, as shown in FIG. 3, it is composed of a photocoupler, and the night power is turned on to the heater power supply terminal 11 by turning on the time switch for the night power (not shown) after entering the power supply time zone of the night power. Then, the voltage is applied through the earth leakage breaker 12, the operation is started, and the midnight power input information is sent to the computing means 9.

The first memory 13 stores various operation commands of the calculating means 9, a plurality of days including the latest day, for example, a water temperature value of the past 7 days, a set temperature (for example, 45 ° C.) regarding the amount of remaining hot water, and the like. Second memory
14 stores hot water temperature control patterns A and B shown in FIG. The third memory 15 stores the moving time (details will be described later) with respect to the total energization time of the upper heater 7 and the lower heater 5, which is predetermined by the feed water temperature, the hot water temperature control pattern, and the remaining hot water amount, as shown in FIG. Remember. Setting operation means 16
Selects one of the two hot water temperature control patterns A and B, and is constituted by a push button type changeover switch 17 as shown in FIG. 6, for example. The output means 18 is, as shown in FIG. 3, a relay 19 for controlling the energization of the upper heater 7.
Also, the relay 20 for controlling the energization of the lower heater 5 is driven.

As shown in FIG. 6, the display means 21 is composed of display elements 21a to 21e such as light emitting diodes for indicating whether the hot water control patterns A and B are large or the amount of remaining hot water is large, medium or small by lighting. It is controlled by the control means 22.

The moving time with respect to the total energization time of the upper heater 7 and the lower heater 5 will be described in detail. When the supply water temperature, the boiling temperature and the remaining hot water amount are determined, the capacity of the tank 3 and the electric power used by the upper heater 7 and the lower heater 5 are known, so that the total energization time can be obtained by calculation. If the midnight power energization time zone is 8 hours, and if the energization time is shorter than the midnight power energization time zone, the non-energization time is the travel time that should be distributed before the total energization time, and after the total energization time. The travel time and the allowance time are obtained by apportioning the allowance time to be distributed at a predetermined ratio, for example, 3: 1. Even if the actual total energization time slightly deviates from the expected total energization time, this travel time is kept constant and there is almost no problem. Therefore, the travel time calculated in advance as shown in FIG. 5 is used. It is stored in the third memory 15.

The movement time is to move the electricity demand from the electric water heater toward the center of the midnight power energization time zone, and the energization time is as late as possible after the midnight power energization time zone to minimize the heat dissipation loss from the tank 3. It is provided for you.

If the hot water is used during the travel time, it is possible that the hot water does not boil up to the specified boiling temperature during the initially expected energizing time, so it is possible to extend the energizing time to prevent the hot water for the user. It is provided to prevent the trouble of cutting as much as possible.

Next, the operation will be described. The calculation means 9 measures the temperature sensor 1 at a predetermined time interval, for example, 1 minute, for 24 hours (this is called the latest day) from the beginning of the midnight power energization time zone to the beginning of the next midnight power energization time zone. Then, the water temperature information converted into a digital value by the A / D converter 8 is fetched. In addition, as shown in FIG. 2, in a time zone other than the midnight power energization time zone in which the upper heater 7 and the lower heater 5 are not energized, as shown in FIG. 2, a mixed layer is formed between the hot water 23 and the water 24 in the tank 3.
25 is formed and the hot water 23 and the water 24 do not mix. Therefore, the temperature sensor 1 can be operated at times other than the midnight power energization time
The water temperature can be obtained by measuring the temperature of the water 24 with.

The calculating means 9 judges whether the taken-in water temperature is the lowest value on the latest day, and if it is the lowest value, the calculating means 9
Change the water temperature value of the latest day stored in the built-in memory to that value and store it.

When the information indicating that the midnight power energization time zone has started is input from the time zone detection means 10, the calculation means 9 performs the feed water temperature calculation processing. The subsequent operation will be described with reference to the flowchart of FIG. The calculating means 9 transfers the water temperature value of the latest day stored in the built-in memory to the first memory 13 and stores it therein. At the same time, the oldest water temperature value is deleted from the first memory 13. Then, including the latest date, multiple consecutive days (7
The water temperature value of (day) is read out from the first memory 13, and the lowest value of them is determined as the water supply temperature of the day.

Next, the calculation means 9 reads the boiling temperature (see FIG. 4) corresponding to the feed water temperature from the hot water temperature control pattern stored in the second memory 14. Further, the amount of remaining hot water is detected. That is, the A / D converter 8 takes in the detected temperature information from the temperature sensors 2a to 2c in time series, sequentially converts the detected temperature information into a digital value, and sends it to the computing means 9. Computing means 9
When the temperature detected by the lower temperature sensor 2a is equal to or higher than the set temperature, a signal for instructing the amount of remaining hot water is sent to the display control means 22,
The display control means 22 turns on the three display elements 21c to 21e together. When the detected temperature of the lower temperature sensor 2a is lower than the specified temperature and the detected temperature of the middle temperature sensor 2b is equal to or higher than the set temperature, a signal indicating the remaining hot water amount is sent to the display control means 22, and the display control means 22 is Both display elements 21d and 21e are turned on. When the detected temperature of the lower temperature sensor 2a and the middle temperature sensor 2b is lower than the set temperature and the detected temperature of the upper temperature sensor 2c is equal to or higher than the set temperature, a signal indicating a small amount of remaining hot water is sent to the display control means 22 and displayed. The control means 22 turns on only one display element 21e. When the temperature detected by the upper temperature sensor 2c falls below the set temperature, a signal instructing the minimum amount of remaining hot water is sent to the display control means 22, and the display control means 22 turns off the three display elements 21c to 21e. The remaining hot water amount detection operation is the same as the water temperature detection operation for 24 hours from the beginning of the midnight power energization time zone to the beginning of the next midnight power energization time zone, not only when the start information of the midnight power energization time zone is entered. The amount of remaining hot water is constantly displayed.

When the computing means 9 determines that the amount of remaining hot water is large,
The moving time (see FIG. 5) corresponding to the feed water temperature, the boiling temperature, and the remaining hot water amount is read from the third memory 15. Then, a built-in timer (not shown) is driven, and after the moving time has elapsed, an upper heater energization command is sent to the output means 18 to energize the upper heater 7. As a result, the hot water 23 above the mixed layer 25 inside the tank 3 is heated, and when it is detected by the upper temperature sensor 2c that it has boiled to the boiling temperature, the power supply to the upper heater 7 is cut off. Immediately thereafter, the lower heater energization command is sent to the output means 18 to energize the lower heater 5. As a result, the mixing layer 25 and water inside the tank 3
When 24 is heated and the temperature sensor 1 detects that it is heated to the boiling temperature, the lower heater 5 is turned off.

When the calculating means 9 determines that the amount of remaining hot water is not large and is in the middle, it immediately energizes the upper heater 7. As a result, the hot water 23 above the mixed layer 25 inside the tank 3 is heated, and when it is detected by the upper temperature sensor 2c that it has boiled to the boiling temperature, the power supply to the upper heater 7 is cut off. After that, the moving time is read from the third memory 15. Then, the built-in microphone is driven to energize the lower heater 5 after the elapse of the moving time. This makes tank 3
When the internal mixing layer 25 and the water 24 are heated and it is detected by the temperature sensor 1 that the temperature has risen to the boiling temperature, the lower heater 5 is deenergized.

When the calculating means 9 determines that the amount of remaining hot water is not large or medium, that is, is small (including a very small amount), it immediately energizes the upper heater 7. As a result, the hot water 23 above the mixed layer 25 inside the tank 3 is heated, and when it is detected by the upper temperature sensor 2c that it has boiled to the boiling temperature, the power supply to the upper heater 7 is cut off. After that, when the amount of remaining hot water is small, as shown in FIG. 5, the moving time is zero. Therefore, it is determined whether there is moving time, and if the moving time is zero, immediately. Energize the lower heater 5. If there is a moving time, the moving time is stored in the third memory.
It is read from 15 and the built-in timer is driven, and after the moving time, the lower heater 5 is energized, the mixed layer 25 inside the tank 3 and the water 24 are heated, and it is detected that the temperature sensor 1 has boiled to the boiling temperature. Then, the lower heater 5 is turned off.

The distribution of the moving time, the energizing time, and the margin time is as shown in FIG. 7 depending on the amount of remaining hot water. In addition, in the case of FIG. 7 and FIG. 8, when the capacity of the tank 3 is relatively small,
Among the remaining hot water amount, the upper heater 7 is immediately energized immediately after the start of the midnight power energization time period. However, when the capacity of the tank 3 is relatively large, when the remaining hot water amount is medium, it is the same as when the remaining hot water amount is large. It is better to continuously energize the upper heater 7 and the lower heater 5 after the movement time has elapsed from the start of the midnight power energization time zone.

According to the present embodiment, when the amount of remaining hot water is small, the upper heater 7 is energized immediately after the start of the midnight power energization time period, so that it is possible to quickly secure the required amount of hot water for the time being. When the amount of remaining hot water is large, the amount of hot water required for the time being can be covered by the amount of remaining hot water, so the energization of the upper heater 7 is delayed by the movement time, thereby shifting the power demand of the electric water heater to the center of the midnight power energization time zone. It is possible to reduce the heat radiation loss from the tank 3 as much as possible.

(Modification) In the illustrated embodiment, the moving time is calculated in advance and stored in the third memory 15, but the calculating means 9 calculates the total energizing time each time, and moves from the total energizing time. Alternatively, the time zone detecting means 10 detects the midnight power supply time zone, but the calculating means 9 has a built-in time switch function for detecting the midnight power supply time zone. May be. In that case, the time zone detecting means 0 is unnecessary.

When the amount of remaining hot water is large, the upper heater 7 and the lower heater 7 are continuously energized, but they may not be continuous and may be left for some time.

(Effects of the Invention) As described above, according to the present invention, when the total energization time of the upper heater and the lower heater is expected to be shorter than the specific time zone, the non-energization within the specific time zone is performed. The time is proportionally divided into a moving time to be distributed before the total energizing time and a margin time to be allocated after the total energizing time, and when the amount of remaining hot water is larger than a predetermined amount, the upper heater and The moving time is taken before energizing the lower heater, and when the amount of remaining hot water is smaller than a predetermined amount, a calculating means for providing the moving time is provided between energizing the upper heater and energizing the lower heater. Therefore, when the amount of remaining hot water is less than the predetermined amount, the upper heater is energized immediately at the start of the specific time zone to focus on securing the amount of hot water. When the start of energization is specified By shifting the travel time from the start of the interzone, the emphasis was placed on the shift in power demand, so that the amount of hot water needed for the time being could be secured promptly and contributed to averaging the total power demand of power companies. And can be achieved at the same time.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a sectional view showing an outline of the tank, FIG. 3 is a circuit diagram showing a heater circuit thereof, and FIG. 4 is a temperature control pattern thereof. 5 and 5 are diagrams showing the movement time, FIG. 6 is a front view showing the operation panel surface, and FIG. 7 is the movement time, energization time,
FIG. 8 is a diagram showing an example of distribution of the margin time, and FIG. 8 is a flowchart showing an example of the operation. 1 ... Temperature sensor, 2a, 2b, 2c ... Temperature sensor, 3 ... Tank, 4 ... Water inlet, 5 ... Lower heater, 6 ... Hot water inlet, 7 ... Upper heater, 9 ... Computing means , 13 first memory, 14 second memory, 15 third memory, 18 output means.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satoshi Watanabe 2-2-7 Higashigotanda, Shinagawa-ku, Tokyo Osaki Electric Industry Co., Ltd. (56) Reference JP-A-57-166443 (JP, A) Kai 61-11548 (JP, A) JP 63-15038 (JP, A) JP 63-131952 (JP, A)

Claims (1)

[Claims] 1. A lower heater disposed near a water supply port at a lower portion of a tank, and an upper heater disposed near a hot water supply port at an upper portion of the tank, and energizing the upper heater to the lower heater during a specific time period. In the hot water storage type electric water heater that gives priority to the energization of, when it is expected that the total energization time of the upper heater and the lower heater is shorter than the specific time zone, the non-energization time within the specific time zone, When the amount of remaining hot water is greater than a predetermined amount, the moving time to be distributed before the total energizing time and the margin time to be distributed after the total energizing time are proportionally distributed to the upper heater and the lower heater. When the moving time is taken before the energization and the amount of remaining hot water is less than a predetermined amount, a calculating means for taking the moving time is provided between the energization of the upper heater and the energization of the lower heater. Storage-type electric water heater to be.