JPH0486452A - Hot water storing type electrical hot water heater having additional boiling function - Google Patents

Abstract

PURPOSE:To provide an upper limitation in the number of additional boiling operations and enable an application of electrical power to be saved by a method wherein an electrical hot water heater is provided with means for setting the number of times of additional boiling operations for setting the upper limit number of times of additional boiling operations within a predetermined time and an additional boiling control means. CONSTITUTION:A hot water storing type electrical hot water heater is comprised of means 3 for setting the number of times of additional boiling operations for use in setting the upper limit number of times of boiling operations within a predetermined time, a remained time calculating means 5 and a remained number of times calculating means 6. An additional boiling control means 7 detects a temperature lower than a predetermined value with a temperature sensor 8 in the case that the upper limit number of times of additional boiling operations is set by the additional number of times of boiling operations setting means 3. In the case that a result of calculation of a remained time calculation means 5 has a remained time and a result of calculation of the remained number of times calculation means 6 is present, an additional boiling signal is outputted and an electrical heater 4 is electrically supplied with electricity to boil up to a target temperature and in turn when the remained number of times is not present and the remained time is not present, the additional boiling control is stopped. With such an arrangement, the upper limit number of times of additional boiling is attained and an electrical power is not applied by more than that required.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hot water storage type electric water heater having a reheating function.

[Conventional technology] As a general rule, storage type electric water heaters boil water in a tank to a target temperature using inexpensive electricity during the night, and are used in bathrooms,
It supplies hot water to kitchens, etc.

By the way, the capacity of the tank is limited to 3702, for example. For this reason, the boiled water may be used up. To solve this problem, a reheating function has been devised to reheat the hot water needed during the daytime to prevent hot water from running out.

FIG. 6 shows a schematic diagram of a conventional hot water storage type water heater.

A water supply port 11 for supplying water into the tank 2 is provided at the bottom of the tank 2 . Furthermore, a hot water supply port 13 is provided at the top of the tank 2 for discharging the boiled hot water. A heating element 4 is provided inside and below the tank 2. Further, a control sensor 8 (thermistor) is attached to the outer wall and lower part of the tank 2 as a temperature detection sensor. Night time period (PMII:
00 to AM7.00), power from the commercial power supply 102 is applied to the heating controller 108 via the changeover switch 106 of the system switching device 104. During the day, electricity is supplied at a higher rate than during the night (7:00 AM to 1:0 PMI)
0), power from the commercial power source 110 is transferred to the grid switch 10
4 to a heating controller 108 via a changeover switch 106. A control sensor 8 , a timer 112 , and a daytime power setting device] 14 are connected to the heating controller 108 . The timer 112 notifies the heating controller 108 of time AM7.00, time PMII:00, and time PM5:00.

The daytime power setting device 114 is composed of a push button switch, etc.
This is to set whether or not there is a request for daytime power use. During the night, the heating controller 108 turns on the commercial power supply 1 at an appropriate time.
Electric power is supplied from 02 to the heating element 4 to boil the water in the tank 2.

If daytime power usage request is set in the daytime power setting device 114, it is daytime and AM7°0
Reheating is possible between 0:00 PM and 5:00 PM. When using boiled hot water, hot water is discharged from the hot water supply port 13 and water is injected from the water supply port 11.

If the amount of hot water used is, for example, 50F, the interface α between the upper layer hot water and the lower layer water is at the installation position of the control sensor 8,
The temperature detected by the control sensor 8 decreases.

When the temperature detected by the control sensor 8 becomes lower than the boiling temperature, the heating controller 108 connects the commercial power supply 11 to the heating element 4.
Supply power from 0 to boil up to boiling temperature (
additional fire). When PMS-00 is reached, the heating controller 108 stops supplying power from the commercial power supply 110 in response to a signal from the timer 112.

Such a conventional technique is described in Japanese Patent Application Laid-Open No. 1-239344.

[Problems to be Solved by the Invention] However, conventional hot water storage type electric water heaters have the following problems.

First of all, there was no limit to the number of reburns.

For this reason, it was decided that the fire would be reheated any number of times between 7:00 AM and PMS.oo. Therefore, expensive daytime electricity is used again and again, which is not economical.

Second, even if the tank is surrounded by a heat insulating material and kept warm, the temperature of the hot water in the tank 2 will decrease over time. Despite this, when the temperature detected by the temperature sensor falls below the boiling temperature, additional heating is performed. For this reason, even if no hot water was used at all, if the temperature of the hot water dropped even slightly, additional heating was required.

Therefore, even when additional heating is not necessary, additional heating is required and expensive daytime electricity is used, which is not economical.

An object of the present invention is to solve the above-mentioned technical problems and provide a hot water storage type electric water heater having a reheating function with improved economical efficiency.

[Means for Solving the Problems] FIG. 1 shows an overall configuration diagram of a hot water storage type electric water heater having a reheating function according to the present invention.

This hot water storage type electric water heater has a reheating number setting means 3 for setting the upper limit number of reheatings that can be performed within a predetermined time, and an upper limit number of reheating times is set by the reheating number setting means 3. the remaining time calculation means 5 which calculates the remaining time of a predetermined predetermined time if The remaining number calculation means 6 calculates the remaining number of reheating by subtracting from the number of reheating, and when the upper limit number of reheating is set by the reheating number setting means 3, the temperature detection sensor 8 detects a temperature lower than a predetermined temperature. When the temperature is detected, and the calculation result of the remaining time calculation means 6 indicates that there is a remaining time, and the calculation result of the remaining number of times calculation means 5 indicates that there is a remaining number of times, a reheating signal is outputted to supply power to the heating element 4. and reheat to the target temperature, and there are no remaining times, or
A reheating control means 7 is provided which stops reheating control when there is no time remaining.

The predetermined temperature is set to a temperature below the boiling temperature and near the upper limit of the temperature of water supplied throughout the year.

[Function] In the hot water storage type electric water heater having a reheating function according to claim (1), the upper limit number of times of reheating that can be performed within a predetermined time is set from the reheating number setting means 3.

The remaining time calculating means 5 calculates the remaining time of a predetermined predetermined time when the upper limit number of times of reheating is set by the reheating number setting means 3.

Each time the remaining number of reheating calculation means 6 receives the reheating signal from the reheating control means 7, it subtracts from the upper limit number of reheatings set by the reheating number setting means 3 to calculate the remaining number of reheatings.

The reheat control means 7 determines that when the upper limit number of reheats is set by the reheat frequency setting means 3, the calculation result of the remaining time calculation means 6 indicates that there is a remaining time, and the calculation result of the remaining number calculation means 5 indicates that there is a remaining time. When there is a remaining number of times, reheating control is performed. That is, if the temperature detected by the temperature detection sensor 8 becomes less than a predetermined temperature, a reheating signal is output and power is supplied to the heating element 4 to perform reheating.

Further, the reheating control means 7 stops the reheating control when there is no remaining number of times or no time remaining.

Therefore, the upper limit on the number of additional fires is limited, and the use of expensive daytime electricity in excess of the limit is reduced.
Economic efficiency is improved.

In the hot water storage type electric water heater having a reheating function according to claim (2), in claim (1), the predetermined temperature is a temperature below the boiling temperature, and water is supplied throughout the year. The temperature is set near the upper limit of water temperature.

Therefore, even if the temperature of the hot water in tank 2 drops to some extent, additional heating using expensive daytime electricity is no longer required, and additional heating is performed only when low-temperature water is supplied. Economic efficiency is improved.

[Example] Hereinafter, the present invention will be described in detail based on the drawings.

FIG. 2 is a circuit diagram of one embodiment of the present invention, and parts corresponding to the inventive configuration diagram of FIG. 1 and the conventional example of FIG. 6 are given the same reference numerals.

The tank 2 has a capacity of, for example, 370P, and is housed in the external device 7. Between the tank 2 and the external device 7,
It is filled with a heat insulating material (not shown).

A water supply port 11 for supplying water into the tank 2 is provided at the bottom of the tank 2 . Furthermore, a hot water supply port 13 is provided at the top of the tank 2 for discharging the boiled hot water. A heating element 4 is provided inside and below the tank 2. The power supply from the commercial power supply 1 to the heating element 4 is controlled by the control section 20 of the main body board 18. Further, a control sensor 8 (-'J--Mister) is attached to the outer wall and lower part of the tank 2 as a temperature detection sensor. The capacity of the tank 2 below the installation position of the control sensor 8 is
For example, it is 50Q.

On the other hand, on the outer wall and upper part of the tank 2, a residual hot water sensor 10,
12.14 is provided. These remaining hot water sensors 10
．． 12.14 is composed of a temperature detection element such as a thermistor or a posistor. Three remaining hot water sensors 10°12, 1
The detected temperature of No. 4 is sent to the control section 20.

The main body board 18 is provided with a power supply circuit 19, a control section 20, a relay 34, a relay driver 64, and a serial communication circuit 66. Although the main body board 18 is shown outside the outer device 7 for convenience of illustration, it is actually housed inside the outer device 7. This main body board 18 can be easily replaced by opening Q17a. The power supply circuit 19 converts AC power from the commercial power supply 1 into DC power of about 5 V, and supplies the power to the control unit 20 and the like. Further, the power supply circuit 19 has a backup power supply, and can supply power to the control unit 20 even in the event of a power outage.

The control section 20 is composed of a one-chip microcomputer, and includes a CPU 50, a ROM 52, a RAM 54, a clock 56, an A/D converter 58, and a multiplexer 60. These are connected to each other by a bus 62. The control sensor 8 and remaining hot water sensors 10, 12, and 14 are connected to the multiplexer 60, respectively. The bus 62 also includes a relay driver 64 that drives the relay 34.
A serial communication circuit 66 that communicates with a remote control box 72 via a cable 70 is also connected. The remote control box 72 is used to set the boiling temperature, set the upper limit number of reheating times, monitor the water temperature, and monitor the amount of remaining water.

The CPU 50 switches the multiplexer 60 as appropriate according to a program stored in advance in the ROM 52.
Control sensor 8, remaining hot water sensor 10. 12. Take in the temperature of water in tank 2 detected in 14. This captured temperature is converted into a digital signal by the A/D converter 58 and stored in the RAM 54. Further, the CPU 50 is R
It periodically communicates with the remote control box 72 according to a program stored in the OM 52 in advance.

The commercial power source 1 is connected to the heating element 4 via the relay switch 36 of the relay 34 and the overheating preventer 15. Commercial power supply 1
supplies electricity at a low rate during the night.

During the day, electricity is supplied at a higher rate than during the night.

The overheat prevention device 15 stops power supply from the commercial power source 1 when the temperature of the hot water abnormally rises due to a failure of the control sensor 8 or the like.

Boiling the water in the tank 2 during the night time is performed as follows.

The boiling temperature is set by pressing the boiling switch 74a of the remote control box 72. Depending on the number of times the boiling switch 74a is operated, the display on the boiling temperature display elements 78e, 78f, 78g, and 78h is sequentially changed to the desired boiling target temperature θ. can be set. For example, the temperature can be set to 85° C., 75° C., or a temperature left to the control of the control unit 20. This target temperature θ. is sent from the remote control box 72 to the CPU 50 via the cable 70 and the serial communication circuit 66, and is stored in the RAM 54 (see FIG. 3). on the other hand,
During boiling, the control sensor 8, residual water sensor 10.
12. 14, detect the temperature of the water in tank 2 and
It is stored in AM54 and the boundary surface α is estimated. As a result, the temperature of the remaining hot water in the layer above the boundary surface α, the amount of remaining hot water, and the temperature of the water in the layer below are determined. In addition, the amount of remaining hot water can be determined by checking the remote control box 7.
This is displayed by lighting up the remaining hot water monitor display elements 78a, 78b, and 78c.

In principle, the CPU 50 determines the temperature of the remaining hot water, the amount of remaining hot water, the temperature of the water in the lower layer, and the heating capacity of the heating element 4 so that the boiling is completed at 7:00 AM, the end time of the night time period. The raising start time is determined and stored in the RAM 54. When the clock 56 indicates the boiling start time, the CPU 50 sends a signal to the relay driver 64 to drive the relay 34 and make the relay switch 36 conductive. When the relay switch 36 becomes conductive, AC power from the commercial power source 1 or the overheat preventer 196 is applied to the heating element 4 . As a result, heating of the water in the tank 2 is started.

After starting heating, the CPU 50 determines the temperature θ detected by the control sensor 8.
, (see FIG. 3) are taken in via the multiplexer 60 and the Δ/D converter 58. Then, the target temperature θ is set in the RAM 54. Determine whether it matches or not. When the detected temperature θ of the control sensor 8 matches the boiling temperature, C
PU50 sends a signal to relay driver 64 to drive relay 34 and shut off relay switch 36. When the relay switch 36 is cut off, power supply to the heating element 4 is stopped. This completes the heating of the water in the tank 2.

In this way, the water in the tank 2 can be raised to the desired boiling temperature.

When boiled hot water is used during the daytime, hot water is supplied from the hot water supply port 13 at the top. Water is supplied from the lower water supply port 11 in an amount equal to the amount of hot water used, and the inside of the tank 2 is always maintained in a filled state.

When water is supplied from the water supply port 11, this water does not mix with hot water and forms a boundary surface as shown by α in the figure.

Next, setting of the upper limit number of rear-end collisions and rear-end collision control will be explained.

By pressing the rear-end collision switch 74b of the remote control box 72, the upper limit number of rear-end collisions is set.

Depending on the number of times the rear-end collision switch 74b is operated, the display on the rear-end collision display element 78i and the display on the 7-segment display element 76 are sequentially switched, and a desired upper limit number of rear-end collisions can be set. If the rear-end collision switch 74b is pressed while rear-end collision is not set, the rear-end collision display element 7
8i lights up, "01" is displayed on the 7-segment display element 76, and the upper limit of the number of rear-end collisions can be set to one.

When the rear-end collision switch 74b is pressed again, the rear-end collision display element 78i lights up, and the 7-segment display element 76 shows "
02" is displayed, and the upper limit of the number of rear-end collisions can be set to two. In this way, the upper limit number of rear-end collisions can be set to 3 or 4. Note that if the rear-end collision switch 74b is pressed when the display is "04", the rear-end collision display element 7
8i lights up and "-1" is displayed on the 7-segment display element 76. This "-1" means that the upper limit number of rear-end collisions is infinite. Additionally, if the rear-end collision switch 74b is pressed when the display is "-1", the rear-end collision display element 78
The i and 7 segment display elements 76 are turned off, and the upper limit number of rear-end collisions can be set to "0", that is, there is no rear-end collision.

This upper limit number of rear-end collisions is sent from the remote control box 72 to the CPU 50 via the cable 70 and the serial communication circuit 66.

The CPU 50 follows the program in the ROM 52.
Execute rear-end collision settings and rear-end collision control. remote control box 72
The upper limit number of rear-end collisions transmitted from the vehicle is stored in the storage area (2) of the RAM 54 (see FIG. 3). Further, this upper limit number of rear-end collisions is stored in the storage area (2) of the RAM 54 as the remaining number of rear-end collisions. When the upper limit number of rear-end collisions is set, the CPU 50 stores the possible rear-end collision time, for example 24 hours, in the ROM 52.
, and store it in storage areas ■ and ■. clock 56
To measure the time, subtraction is immediately started from the possible rear-end collision time stored in the storage area (2), and the remaining time T is calculated. Further, when the upper limit number of rear-end collisions is set, the CPU 50 sets the rear-end collision start temperature θ, which is a predetermined temperature, to R.
Read from OM52 and store in storage area (■).

Note that the rear-end collision start temperature θ is a temperature lower than the boiling temperature, and is set to a temperature near the upper limit of the temperature of water supplied throughout the year, for example, 50°C. The temperature of water supplied in winter is, for example, 10°C, and the temperature of water supplied in summer is, for example, 35°C at the upper limit. Therefore, if the rear-end collision start temperature θ is set to 50° C., the supplied water will not be mistakenly recognized as hot water. In addition, the heated hot water in tank 2 will change over time in winter.
For example, the temperature may drop by about 5°C to 80°C. However, even if the temperature of the hot water decreases, the rear-end collision starting temperature θ.

The temperature never drops below 50°C. Therefore, hot water will not be mistaken for water.

Furthermore, when the upper limit number of rear-end collisions is set, the CPU 50 sets a rear-end collision flag in the storage area (2). This rear-end collision flag is a flag indicating whether or not a rear-end collision will occur. That is, the rear-end collision flag is set unless the number of rear-end collisions is set to "0".

FIG. 4 shows a flowchart of the rear-end collision control program stored in the ROM 52.

In step m, it is first determined whether the rear-end collision flag is set. If the rear-end collision flag is not set, steps m2 to m1. Terminates without executing. Then, after a predetermined period of time has elapsed, execution is performed again from step m.

If the rear-end collision flag is set, the process proceeds to step m2, and it is determined whether or not the remaining time T (■ in FIG. 3) remains.

If the remaining time T remains, the process proceeds to step m3, and it is determined whether the remaining number of times n (■ in FIG. 3) remains.

If the remaining number of times remains, the process advances to step m4, and the detected temperature θ of the control sensor 8 becomes the rear-end collision start temperature θL (■ in Fig. 3).
). If the rear-end collision start temperature is less than 01, power is supplied to the heating element 4 (step m s), RAM
A rear-end collision flag is set in the storage area 54 (see FIG. 3) as a rear-end collision signal (step m6), and the process ends. Then, after a predetermined period of time has elapsed, execution is performed again from step m.

In step m4, if the detected temperature θ of the control sensor 8 is not less than the rear-end collision start temperature θ1, the process proceeds to step m7, and it is determined whether the rear-end collision flag is set. If the rear-end collision flag is not set, the process ends. Then, after a predetermined period of time has elapsed, execution is performed again from step m1. If the rear-end collision flag is on, it means that a rear-end collision is currently occurring. In this case, the CPU 50 determines whether the temperature θ detected by the control sensor 8 has reached the target temperature θ. If not equal, exit. Then, after a predetermined period of time has elapsed, execution is performed again from step m. Target temperature θ. If it reaches step m9, the power supply to the heating element 4 is stopped. Also, lower the rear-end collision flag (step m
,. ), to determine whether the upper limit number of rear-end collisions is (1), step m, ), if not ■, in response to the lowering of the rear-end collision flag, set the remaining number n (■ in Figure 3) to "1". Subtractively step m, 2) and end. Further, if the upper limit number of rear-end collisions is 2, the process ends without subtracting the remaining number n.

The remaining time T (■ in Figure 3) runs out (step m
2), when the remaining number n (■ in Figure 3) is exhausted (step m3), the power supply to the heating element 4 is stopped (steps m, a), and the rear-end collision flag is lowered (step m+4).
), lowers the rear-end collision flag (step m, 6), and ends the process.

Next, as shown in FIG. 5, assume that the user is likely to use a lot of hot water the next day, so the upper limit number of rear-end collisions is set to 3 using the remote control box 72 at 9:00 PM.

It is assumed that a large amount of hot water remains in the tank 2, and the temperature θ detected by the control sensor 8 is higher than the boiling start temperature θ. Therefore, Ste Soph mH, m2. m3.
From m4 to step m7. Go to m and exit. Therefore, no rear-end collision occurs between 9:00 PM and 11:00 PM. At night, boiling begins (see α in Figure 5) and is completed a little before 7°00 AM (see α2 in Figure 5).

It is assumed that hot water of 502 or more is used three times during the daytime. In usage 1 and 2.3, when 50 degrees of hot water is used, the control sensor 8 detects the water temperature below the collision start temperature θ1 (step m4), and the rear collision 12.3 is started (step ms, as shown in FIG. 5). β.

β2. (see β8). In rear-end collisions 1 and 2, the time limit and number limit of steps m1 and m2 are not violated.

Therefore, the target temperature θ. A rear-end collision occurs until
．． γ, see). In rear-end collision 3, 24 hours have passed during the rear-end collision. Therefore, the time limit in step m2 is violated, and the power supply is stopped before the rear-end collision is completed (step m1s, see 73 in FIG. 5). In addition, use 3 is PM
If the rear-end collision is carried out well before 9:00, the time limit of step m2 will not be violated and the rear-end collision will be completed in the same manner as in Use 1.2. In addition, if the number of times limit of 3 times is exceeded or the time limit of 24 hours is exceeded, step m,
Since the rear-end collision flag is lowered in step 5, the vehicle will not be rear-ended unless the upper limit number of rear-end collisions is set again.

Note that when the night time zone enters during the rear-end collision, the CPU 50 shifts from the rear-end collision to the normal night time zone heating and performs the boiling.

In the above-mentioned embodiment, the number of rear-end collisions setting means 3, the remaining time calculation means 5, the remaining number of times calculation means 6, and the rear-end collision control means 7 are replaced by the rear-end collision switch 74b, the CPU 50, the ROM 52, and the RAM.
54 hardware and ROM52 programs,
Although it is configured by software for the data in the RAM 54, it may also be configured by logic, network circuits, etc.

Further, in the above-described embodiment, the possible rear-end collision time may be set to 24 hours, or may be set to another time such as 2 days or 1 week, or may be set freely.

Also, the starting temperature for rear-end collision was set at 50 degrees Celsius, or 40 degrees Celsius.
The temperature may be set closer to the upper limit of 35°C of the temperature of water supplied in summer, such as 30°C, or may be freely set.

Furthermore, although power is supplied from one system of commercial power source 1, if the commercial power sources for nighttime and daytime hours are different, power may be supplied using a system switch 104 as shown in FIG. .

[Effects of the Invention] As described above, the hot water storage type electric water heater having a rear-end collision function according to claim (1) allows the upper limit number of rear-end collisions to be set.

Therefore, the upper limit of the number of rear-end collisions is limited, the use of expensive daytime electric power is reduced, and economic efficiency is improved.

In the hot water storage type electric water heater having a rear-end function according to claim (2), in claim (1), the predetermined temperature is a temperature below the boiling temperature, and the water is supplied throughout the year. The temperature is set near the upper limit of the temperature.

Therefore, even if the temperature of the hot water in the tank 2 drops to some extent, a rear-end collision that uses expensive daytime electricity will not occur, and a rear-end collision will occur only when low-temperature water is supplied, which is economical. is improved.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the overall configuration of the present invention, FIG. 2 is a circuit diagram of an embodiment of the present invention, FIG. 3 is a diagram showing a memory map of the RAM 54, and FIG. 4 is a flowchart for explaining rear-end collision control. , FIG. 5 is a diagram for explaining the state of a rear-end collision when the upper limit number of rear-end collisions is set to three, and FIG. 6 is a schematic diagram of a conventional hot water storage type electric water heater. 1... Commercial power supply 2... Tank 3... Rear-end collision number setting means 4... Heating element 5... Remaining time calculating means 6... Remaining number of times calculating means 7... Rear-end collision control means 8. ...Temperature detection sensor (control sensor) Patent applicant Sekisui Chemical Co., Ltd. Figure 3

Claims (2)

[Claims] (1) During the night, late-night electricity is supplied to the heating element to boil the water in the tank, and during the day, the temperature sensor installed at a predetermined position on the outer wall of the tank boils the water in the tank. In a hot water storage type electric water heater that detects the water temperature and, when it detects that the water temperature is lower than a predetermined temperature, supplies daytime electricity to the heating element and reheats the water in the tank, A reheating number setting means for setting the upper limit number of reheatings that can be reheated within a time, and calculating the remaining time of a predetermined time when the upper limit number of reheatings is set by the reheating number setting means. Remaining time calculation means for calculating the remaining number of reheatings by subtracting from the upper limit number of reheatings set by the reheating number setting means each time the reheating signal is received from the reheating control means. When the upper limit of reheating times is set using the reheating number setting means,
When the temperature detection sensor detects a temperature lower than a predetermined temperature, the calculation result of the remaining time calculation means indicates that there is time remaining, and the calculation result of the remaining number of times calculation means indicates that there are remaining times, the reheating signal is output. The reheating function is characterized by being equipped with an additional heating control means that outputs power to the heating element to reheat up to the target temperature, and stops the reheating control when there are no remaining times or no time remaining. A hot water storage electric water heater. (2) Claim (1) characterized in that the predetermined temperature is set to a temperature lower than the boiling temperature and near the upper limit of the temperature of water supplied throughout the year.
A storage type electric water heater with additional heating function.