JPH0243985B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hot water storage type electric water heater that utilizes late-night electricity.

Conventionally, in hot water storage type electric water heaters that use Fukano Electric Power, there have been control devices that control the boiling temperature to save electricity costs (for example, Japanese Patent Application Laid-Open No. 1983-1999)
(See Publication No. 120045).

However, since this control device calculates the required boiling temperature from the preset required amount of hot water to be used and the water supply temperature, it is necessary for the user to perform an operation to set the required amount of hot water to be used.

Normally, when setting the required amount of hot water to be used, users set the required amount of hot water a little higher for fear of running out of hot water, so a large amount of hot water is often left behind.

For this reason, there is a problem in that heat loss due to natural heat radiation from the hot water storage tank and heat radiation from hot water accumulated in the pipes increases, and hot water supply efficiency with respect to electricity charges decreases.

Furthermore, since the required amount of hot water varies greatly throughout the year, users must frequently change the set value for the required amount of hot water.

Moreover, each time the amount of remaining hot water increases significantly,
It may cause the hot water to run out.

[Purpose of the invention]

In view of these conventional problems, the present invention detects the amount of hot water remaining in the hot water storage tank and can control the optimal amount of hot water without running out of hot water or overboiling. The purpose of the present invention is to provide a control device for a hot water storage type electric water heater.

[Structure of the invention]

As shown in FIG. 1, the present invention has a configuration in which the amount of remaining hot water in a hot water storage tank is stratified into a plurality of hot water amount ranges in the vertical direction of the hot water storage tank, and the amount of remaining hot water divided into layers is detected as a hierarchical value. The hot water amount detecting means a detects the amount of hot water remaining in the hot water storage tank for one day as a hierarchical value, and the unit number of days of the hierarchical value of the remaining hot water amount is stored in the storage means b.

Then, when the minimum value of the hierarchy value of each residual hot water amount stored in the storage means b is equal to or higher than the preset standard residual hot water amount value, the temperature is unfavorably corrected by the first boiling temperature correction means c. When the water is boiled up to the boiling temperature, the hierarchical value of the remaining hot water amount for one day detected by the remaining hot water amount detection means a by the second boiling temperature correction means d is equal to the preset minimum margin residual hot water amount. The boiling temperature is adjusted upward when the temperature is below the specified value.

〔Example〕

The present invention will be described below with reference to embodiments and the drawings.

In FIG. 2 showing the hardware of a hot water storage type electric water heater, 1 is a hot water storage tank, and a heater 2 and a hot water temperature sensor 3 are respectively disposed at the lower side wall of the hot water storage tank 1. A plurality of hot water flow sensors 4a, 4b, . . . 4e are arranged on the side wall at regular intervals in the vertical direction.

The heater 2 is energized by a 200V late-night power source 5, and uses late-night power (power from 11 p.m. to 7 a.m. the next morning) to bring the water supplied to the hot water storage tank 1 to a predetermined temperature. It's something to stir up.

Hot water temperature sensor 3 and each hot water amount sensor 4a, 4b,
...4e are each connected to the output side of the microcomputer 10.

The microcomputer 10 mainly includes a CPU (central processing unit) 11, a ROM 12, and a RAM 13.
and an input/output interface 14.

In FIG. 1, 7 is an interface circuit, 8 is a water supply pipe, and 9 is a hot water pipe.

The hot water quantity sensors 4a, 4b,...4e are temperature sensors that detect the position of the boundary between hot water and water.For example, the hot water quantity sensor 4a senses the temperature of hot water, and the hot water quantity sensor 4b can be used as hot water. When a relatively low hot water temperature or water temperature is being sensed, the boundary between hot water and water exists between the lower hot water amount sensor 4a and the upper side of the hot water amount sensor 4b.

In this way, the amount of remaining hot water is not an absolute value, but is measured above the hot water amount sensor 4a, between 4a and 4b, and between 4b and 4b.
C, between 4c and 4d, between 4d and 4e, and below 4e, each level is given a code, and this is called the level value of the amount of remaining hot water.

When the hierarchical value of the amount of remaining hot water detected by the hot water amount sensors 4a, 4b, . The boiling temperature is calculated according to the data.

When the value of the water temperature detected by the water temperature sensor 3 reaches the calculated boiling temperature value, an output signal from the computer 10 is input to the automatic temperature controller 6, and the power supply to the heater 2 is stopped. It is something that

Note that the start of energization of the heater 2 may be started at the moment when the power source 5 is supplied, or the start time may be shifted by the microcomputer 10.

Each step of a flowchart for carrying out the above-mentioned control is shown.

In step, it is determined whether the remaining hot water amount value for that day is less than or equal to the minimum margin remaining hot water amount value (x).

The value (x) of the minimum residual amount of hot water is the minimum amount of hot water that is considered to be necessary as the amount of remaining hot water for one day, and is set in advance to prevent hot water from running out.

If the remaining hot water amount value is equal to or greater than the minimum allowance remaining hot water amount value (x), the process advances to step 100, where this calculation date is read as the 1st day, and at the same time, the remaining hot water amount value for that day is stored.

In the step, it is determined whether the number of days counted in the step has reached the unit number of days (Y days).

If the unit number of days has not been reached, go to NEXT.

If the unit number of days has been reached, in step, the remaining hot water amount values stored for each day of the unit number of days are all greater than or equal to the first standard remaining amount of hot water, that is, three times or more the value of the minimum margin remaining amount of hot water (x). Determine whether or not.

If all the stored remaining hot water amount values are three times or more of (x), in step, the boiling temperature for the next unit of days is lowered by 2α℃ from the current boiling temperature, and in step, the counted unit is Return the number of days to zero.

If the stored remaining hot water amount value is 3 times or less of at least one remaining hot water amount value (x), step (6) is performed.
Then, it is determined whether the remaining hot water amount values stored for each unit number of days are all equal to or higher than the second reference residual hot water amount, that is, twice or more of (x).

If all the stored remaining hot water amount values are more than twice (x), in step, the boiling temperature for the next unit of days is lowered by α℃ from the current boiling temperature, and in step, the counted unit is Return the number of days to zero.

On the other hand, if the remaining hot water amount value is less than or equal to (x) in step, proceed to step and increase the boiling temperature for the next day by α℃ from the current boiling temperature. Return to zero.

As described above, by adjusting the boiling temperature once a day and once per unit day, the daily remaining amount of hot water does not fall below (x) to prevent hot water from running out, and also to prevent the amount of hot water from exceeding the required amount. I try not to let it boil over.

In addition, the value (x) of the minimum remaining hot water amount used in the step is, for example, the value of the hot water amount corresponding to the maximum boiling capacity of the electric water heater multiplied by a certain percentage (for example, several %), and this value is primarily a value obtained through statistical calculation or experience, and is given as a risk factor to prevent hot water from running out.

In addition, the constant α used to correct the boiling temperature
is determined from the value (x) of the minimum remaining hot water amount, and is usually about 5 to 10°C.

Furthermore, although the number of days per unit is not limited to five days as in this example, the amount of hot water required for days when bathing and days when not bathing is usually significantly different, so the number of days per unit is not limited to three days or more. It is preferable to determine the number of days or about one week.

FIG. 4 shows a specific example of the execution pattern of the procedure in FIG. 3.

Within the first unit of days (T1), the amount of remaining hot water on all days is more than three times the value of the minimum residual amount of hot water (x), so the set boiling temperature (85℃) for the first unit of days (T1) ), the boiling temperature is lowered by 2α℃ [(85−2α)℃], reducing the boiling capacity in the next unit number of days (T2).

Within the second unit number of days (T2), the amount of remaining hot water on days other than day Y+2 is less than three times the value of the minimum remaining hot water amount (x), and the amount of remaining hot water on all days is the value of the minimum remaining hot water amount. (x), so it is 2α from the set boiling temperature (85℃) in the second unit number of days (T2).
Boiling temperature lowered by °C (85−2α) °C to α
The boiling temperature is lowered by ℃ [85-3α) ℃], and the boiling capacity in the next unit number of days (T3) is reduced.

Within the third unit number of days (T3), the amount of remaining hot water on day Y+1 is more than three times (x), and the amount of remaining hot water on day 2Y+1 is more than twice as much as (x), but the amount of remaining hot water on other days is Since it is more than (x) and less than twice (x), the boiling temperature in the third unit of days (T3) [(85-
3α)℃] is set as the boiling temperature in the next fourth unit of days (T4).

In the fourth unit of days (T4), on day 3Y+2, the amount of hot water remaining on that day became less than (x), so the next day [(3Y
+2)+1st day] The set boiling temperature is increased by α℃ to [(85-2α)℃] to increase the boiling capacity, and the next day is the 1st day of the 5th unit of days. Start as .

〔Effect of the invention〕

As explained above, the control device for the storage type electric water heater of the present invention detects the daily amount of remaining hot water as a hierarchical value, and starts boiling when the daily amount of remaining hot water is less than or equal to the minimum residual amount of hot water. In addition to adjusting the boiling temperature upward, the boiling temperature is also adjusted downward when the stored amount of remaining hot water for the unit number of days exceeds the preset standard residual hot water amount. It is possible to supply just the right amount of hot water according to the usage conditions without the need for manpower.
It is possible to improve the efficiency of hot water storage type electric water heaters.

[Brief explanation of drawings]

The drawings illustrate embodiments of the present invention; FIG. 1 is a block diagram showing the configuration of a control device, FIG. 2 is a schematic diagram showing the overall configuration of a hot water storage type electric water heater, and FIG. 3 is a hot water storage type electric water heater. FIG. 4 is an explanatory diagram of the specific procedure of the control device. 1... hot water storage tank, 2... heater, 3... hot water temperature sensor, 4... hot water amount sensor, 10... microcomputer.

Claims (1)

[Claims] 1 The amount of remaining hot water in the hot water storage tank is divided into a plurality of levels of hot water amount range in the vertical direction of the hot water storage tank, and the remaining hot water amount detection means detects the hierarchical value of the hierarchical classification, and the remaining hot water amount detection means A storage means for storing the detected hierarchical values of the amount of remaining hot water for the unit number of days, and a storage means for storing the hierarchical value of the amount of remaining hot water for the number of unit days stored by the storage means, the minimum value of which is a preset standard amount of remaining hot water. The value of the minimum margin remaining hot water amount that is preset by the first boiling temperature correction means that corrects the boiling temperature downward when the boiling temperature is higher than the value, and the hierarchical value of the remaining hot water amount for one day detected by the remaining hot water amount detection means. 1. A control device for a hot water storage type electric water heater, comprising: second boiling temperature correction means for upwardly correcting the boiling temperature in the following cases.