JPH02169958A - Device to control boiling in electric water heater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in a control device for an electric water heater that uses late-night electricity.

[Prior art] Fig. 11 is a block diagram of a conventional hot water storage type electric hot water type that uses late-night electricity.In the figure, 1 is a hot water storage tank, 2 is a lower heating element, and 3
4 is an upper heating element, 4 is a lower water temperature measuring means for measuring the water supply temperature and the boiling temperature, 5 is an upper water temperature measuring means for measuring the boiling temperature by the upper heating element 3, and 6 is a boiling water temperature measuring means. A hot water temperature setting means for setting the temperature; 7 a calculation means for calculating the net energization time and the energization start time based on the lower water temperature measuring means 4 and the hot water temperature setting means 6; 8 detecting the presence or absence of late-night power supply. The late-night power detection means 9 is based on the information of the calculation means 7, the late-night power detection means 8, and the lower water temperature measuring means 4,
Lower heating element control means performs 0N10FF control of the lower heating element 2; 10 is a reheating setting means for setting energization of the upper heating element 3; 11 is an upper heating element control means for controlling the upper heating element 2 based on information from the reheating setting means 10 and the upper hot water temperature measuring means. This is an upper heating element control means that controls the heating element 3 at 0N10FF.

In this water heater, the lower heating element 4 uses late-night electricity to heat the water supply, but if the amount of hot water used during the day is large, the upper heating element 5 is used to reheat the water.
It is configured to accommodate this.

FIG. 12 is an electrical circuit diagram of the control device for the water heater.

In the figure, 12 is a microcomputer, CPU1
B, memory 14, input circuit 15, output circuit 16, A/D
It is composed of a converter 17 and an analog multiplexer 18.

Reference numeral 19 indicates a circuit of the heating element control means 9, in which a resistor 20
．． 21, a transistor 22, relays 23, 24, diodes 25, 26, etc. The coil of the relay 23 is connected via the transistor 22 between the positive terminal +V and the ground terminal, and the base of the transistor 22 is connected via the resistor 20 to the output terminal 16 of the microcomputer 12. In addition, the normally open contact of relay 23 is
It is connected to the ground terminal via the positive terminal +V1 and the coil of the relay 24, and diodes 25 and 26 are connected to both ends of the relay 23 and 24, respectively. Further, the heating element 2 is connected in series between the normally open contact of the relay 24 and the midnight power source 27.

Reference numeral 28 shows an electric circuit of the heating element control means 11, which is composed of a resistor 29, 30, a transistor 31, a relay 32, and a diode 33. The coil of the relay 32 is connected to the positive terminal +V and the ground terminal via the transistor 31. The base of the transistor 31 is connected to the output circuit 16 of the microcomputer 12 via a resistor 29.

Further, the heating element 3 is connected in series between the normally open contact of the relay 32 and the daytime electric light power supply 34.

The hot water temperature measuring means 4.5 is composed of, for example, a thermistor, and the hot water temperature setting means 6 is composed of a variable resistor. resistance 35
is connected in series with the lower hot water temperature measuring means 4 between the positive electrode terminal +V and the ground terminal, and the connection portion between the resistor 35 and the lower hot water temperature measuring means 4 is connected to the analog multiplexer 18. Further, the resistor 36 is connected in series with the upper hot water temperature measuring means 5 between the positive terminal 10 and the ground terminal.
The connection between the resistor 36 and the lower hot water temperature measuring means 5 is connected to the analog multiplexer 18. Furthermore, resistance 37
is connected in series with the hot water temperature setting means 6 between the positive terminal 10V 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.

38 is a circuit diagram showing the late-night power detection means 8, in which a resistor 39.
40, a diode 41, and a phototransistor 42. The light emitting side of the phototransistor 42 has a resistor 3
A diode 41 is connected in parallel to both ends of the diode 27. On the other hand, one end of the phototransistor 42 on the light receiving side is connected to the positive terminal +V via the resistor 40, and the other end is connected to the ground terminal.
The +[ part of 0 is the input circuit 15 of the microcomputer 12
It is connected to the.

The resistor 43 is connected in series between the overheating setting means 10 consisting of a switch, the positive terminal 10V, and the ground terminal, and the connection between the resistor 43 and the overheating setting means 10 is connected to the input circuit 15 of the microcomputer 12. It is connected.

Next, the operation of the conventional device configured as described above will be explained with reference to the flowchart shown in FIG. Note that this flowchart shows the control means for the heating element 2.3 stored in the memory 14 of the microcomputer 12.

First, as soon as the power is turned on, the presence or absence of late-night power is checked (step 44). If late-night power is supplied, the signal is transmitted to the microcomputer 1 via the phototransistor 42.
2, and starts a timer for counting the elapsed time (step 45). Next, the lower hot water temperature measuring means 4 measures the supply water temperature Tν°C (step 46), and reads the used hot water temperature T'C (step 47).
).

When the heating element capacity is Pkw, the net energization time H is calculated using the following formula (%) where V: Capacity of hot water storage tank ffi (1) 860
: I KVH heat generation fik (XCal) 0.9: Can be calculated using efficiency (step 48).

As a result, the power supply start time Hp can be determined by the CPU 13 using the following formula, assuming that the late-night power supply time is 8 hours (step 49).

Hp-8-H・・・・・・・・・・・・・・・・・・
(2) This calculation is performed in order to shift the energization start time Hp within the late-night power supply time zone and to average out the late-night power load.

Next, it is determined whether the elapsed time by the timer (step 45) has reached the energization start time (step 50). If the energization start time has come, the output signal from the output circuit 16 is transmitted to the transistor of the heating element control circuit 19. 22, the relay is turned on to open the power supply circuit, and power supply to the heating element 2 is started (step 51). Next, the hot water temperature Til in the hot water storage tank 1 is measured by the lower hot water temperature measuring means 4.Step 5
2) Compare Tml with boiling temperature T (step 53
) While Till is smaller than T, the lower heating element 2 continues to be energized, and when Ti1 reaches T, the output signal from the output circuit 16 is cut off, the relay 24 is released, and the power supply circuit to the heating element 2 is switched off. OFF and step 54) ends the control.

If it is determined in step 44 that there is no late-night power supply, that is, it is not the late-night power supply period, it is determined whether the reheating start switch is on or not (step 55). If the switch is on, the upper hot water temperature measuring means 5 In step 56), the upper water temperature Ti2 of the hot water storage tank 1 is measured.
is compared with the boiling temperature T (step 57), Tm2
If <T, turn on the upper heating element (step 58),
If Tm2≧T, the upper heating element is turned off (step 59). Next, in step 60, it is determined whether there is a late-night power supply, and if there is no late-night power supply, 0N is applied to the upper heating element.
10 FF is repeated, and if late-night power is supplied, power to the upper heating element is stopped in step 61, and boiling using the daytime power is ended.

[Problems to be Solved by the Invention] A conventional electric water heater is constructed and operates as described above. That is, boiling by the lower heating element is performed during the late night power supply time period, and heating by the upper heating element is performed during the daytime period other than the above. Therefore, the time for boiling is limited. However, in today's social life where each person has a different lifestyle, such restrictions on the heating time of water supply disrupt the daily rhythm of life and become an obstacle to efficient living.

In addition, if you perform boiling operation using the upper heating element, the power will remain at 0N10F until midnight power supply hours unless you stop it.
Repeating the F operation will result in wasted power consumption, and if you use a large amount of hot water, you are likely to run out of hot water if you forget to reheat it.

Another problem is that control becomes complicated because the energization time of the lower heating element is shifted to the latter half of the midnight period. As described above, conventional water heaters have several problems.

The present invention was made to solve the above-mentioned problems of conventional water heaters, and aims to provide an efficient electric water heater that adapts to the rhythm of daily life.

[Means for Solving the Problems] In order to achieve the above object, an electric water heater according to the present invention includes a hot water storage tank, a lower heating element disposed at a lower part of the tank, and an upper part disposed at an intermediate part of the tank. a heating element, a lower hot water temperature measuring means for measuring the temperature of the hot water in the tank, an upper hot water temperature measuring means for measuring the temperature of the water heated by the heating element disposed in the middle of the tank; energization time zone setting means for setting the energization time zone for the tank lower heating element and the upper heating element; and lower heating element control for controlling the lower heating element based on information from the energization time zone setting means and the lower hot water temperature measuring means. controlling the boiling of the upper heating element based on information from the means, the manual reheating setting means for starting reheating by manual operation, the upper water temperature measuring means, the manual reheating setting means, and the energization time period setting means. and upper heating element control means.

Further, the above-mentioned apparatus is further provided with a residual hot water amount detection means and an automatic replenishment means for performing replenishment according to the residual hot water amount detected by the detection means.

[Operation] The energization time period setting means allows the energization time of the lower heating element and the upper heating element to be arbitrarily set.

In addition, since the configuration is such that the power is not re-energized unless the control is completed by boiling the boiler twice and the operation is performed again, there is no waste due to 0N10FF control.

In addition, the calculation method for freely shifting the energization start time within the late-night power supply time period is omitted, and the boiling start time of the lower heating element starts from the beginning of the set time period, making control easier. Become.

Furthermore, if the amount of hot water used is large, the manual boiling setting means can be used to boil up the water at any time. Furthermore, by providing an automatic reheating means and a residual hot water amount detection means, reheating is automatically performed when the amount of residual hot water decreases, thereby preventing hot water from running out.

[Embodiment of the Invention] Fig. 1 is a configuration diagram of an electric water heater showing an embodiment of the present invention, in which 1 to 7 are the same or equivalent parts as in a conventional water heater;
0 is an energization time zone setting means, 71 is a manual reheating setting means, 72 is an upper heating element control means, and 73 is a lower heating element control means.

In the figure, the energization time zone setting means 70 has a clock function and can arbitrarily set the energization time zone of the lower heating element 2, so that water supply can be heated even at times other than the late-night power supply time zone. It is. Since the upper heating element can be energized by the manual reheating means 71, there is little risk of running out of hot water even when a large amount of hot water is used.

FIG. 2 is an electrical circuit diagram of the above embodiment, with 74.75.
76 and 77 are resistors, which are connected to the power supply +V and the ground terminal in series with the manual retrieval means 71 and the energization time zone setting means 70 each consisting of a switch, and the connection between each switch and the resistor is connected to the input circuit 15 of the microcomputer 12. It is connected to the. The display circuit 78 is the microcomputer 1
The output signal from the second output circuit 16 is amplified. Further, the display means 79 performs display based on the output signal from the display circuit 68.

FIG. 3 is a front view of the operating section and display section of this embodiment, where 80 is the operating section, 81 is a display switching operation button, 82.83 is a time setting operation button, 84 is a display section, 85.86. 8
7 are the current time, the start time of energization to the lower heating element, and
The stop time lamp 88 is a lamp indicating the time.

In the figure, 1. When the power is turned on, a lamp 85 indicating the current time on the display section lights up, and a lamp 88 indicates the current time. When the operation button 81 is operated, the current time lamp 85 is turned off and the energization start time lamp 86 is turned on. Further operation button 8
1, the energization start time lamp 86 goes out and the energization stop time lamp 87 lights up. Further operation button 81
When is operated, the energization stop time lamp 87 goes out and the current time lamp 85 lights up, returning to the initial state.

When setting the time, the lamp 85 indicates the current time.
The lamp 86 indicates the energization start time, and the lamp 8 indicates the energization stop time.
7 is lit, the hours are set using the operating button 82 and the minutes are set using the operating button 83.

Next, the operation of this embodiment will be explained with reference to the flowchart shown in FIG. The flowchart is executed by the microcomputer 12.
This figure shows the heating element control stored in the memory 14, and the same reference numerals as in the conventional example represent the same operations.

At the same time as turning on the power, set the boiling temperature to, for example, 90°C (step 90), then set the current time (step 91), set the energization start time (step 92), and set the energization stop time (step 93). conduct. Next, it is determined whether the energization start time has been reached (step 94).
If the energization start time has been reached, the lower heating element 2 is energized (step 51), and the lower hot water temperature Tml is measured in the same way as the flowchart of FIG. 13 of the conventional device (step 5).
2) Compare the Tl1l with the boiling temperature T (step 53), and continue to apply electricity until Tl11 T.
When this happens, the power supply to the lower heating element 2 is stopped (step 5).
4) Perform the action. In step 94, if it is not the energization start time, it is determined whether manual reheating is set (step 95), and if it is set, the upper heating element 3 is manually energized (step 58). Next, set the upper water temperature Tl12■j
Specifically, in step 56), electricity continues to be applied while Tm2<T, and when Tg+2≧T, the electricity to the upper heating element 3 is stopped (step 54). Note that the boiling up to the temperature T'C is done only once, and even if the water temperature T112 falls below T, the energization is not repeated.

In the case of this embodiment, the time period for energizing the lower heating element 2 can be arbitrarily set regardless of the late-night power supply time period, and the upper heating element is It can be chased by energizing the body only once.

FIG. 5 is a block diagram showing another embodiment of the present invention, FIG. 6 is an electric circuit diagram thereof, and FIG. 7 is a flowchart thereof. In place of the manual reheat setting means of the above embodiment, a remaining hot water amount detection means 100 and an automatic reheat setting means 101 are provided. Note that 102 and 103 in FIG. 6 are resistors.

In the flowchart of Fig. 7, step 90 indicates that the boiling temperature should be set to, for example, 90°C at the same time as the power is turned on.
), then setting the current time (step 91), setting the energization start time (step 92), and setting the energization stop time (
Step 93) is performed.

Next, it is determined whether or not the energization start time has been reached (step 94), and if the energization start time has been reached, the lower heating element 2 is energized (step 51), and the following is the same as the flowchart of FIG. 13 of the conventional device. The lower water temperature Tit is fixed at 7IFJ (step 52), and Tmaro1 is compared with the boiling temperature T (
Step 53) Continue energizing while Tml<T;
When it≧T, the power supply to the lower heating element 2 is stopped (step 54). In step 94, if it is not the energization start time, it is determined whether there is an automatic reheating setting (step 95), and if YES, the remaining hot water amount is detected by the remaining hot water amount detection means 100 (step 96), and if there is no remaining hot water amount ( Step 97) Applying electricity to the upper heating element 3 (Step 5
8). Thereafter, the upper water temperature Tl112 is measured, the current is applied until Ti2 reaches the boiling temperature T, and when Tm2 reaches T, the current is stopped, as in the conventional device. In this embodiment, unlike the above-mentioned embodiments, it is possible to automatically flush out the water.

FIG. 8 is a configuration diagram of an electric water heater showing still another embodiment,
FIG. 9 is its electrical circuit diagram, and FIG. 10 is its flowchart. As shown in FIG. 8, this embodiment further adds a manual retardation setting means 71 to the above embodiment. As a result, as shown in the flowchart, even if the automatic reheating setting means 101 is not set for some reason, the upper heating element 2 is manually forcibly set to Electricity can be applied to heat the water supply.

[Effects of the Invention] In the present invention, since the control device for the electric water heater is equipped with the energization time period setting means, the energization time period to the lower heating element can be arbitrarily set.

In addition, it is equipped with an automatic or manual recharging setting means, so even when the power is not on, the remaining power can be set. When &m decreases, the upper heating element starts to be refilled automatically or manually, and even if the amount of hot water used increases, such as during ceremonial occasions, there is no need to worry about running out of hot water.

Note that the above-mentioned reheating is done only once, and the configuration is such that the power is not re-energized after the boiling is complete, so the 0N1 is wasted.
0FF control is not repeated.

Furthermore, since the boiling start time of the lower heating element is set at the beginning of the time period, there is no need for a complicated calculation device, making control simple.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of an electric water heater that is an embodiment of the present invention.
Fig. 2 is its electric circuit diagram, Fig. 3 is a front view of the operating section and display section, Fig. 4 is a flowchart showing the operation, Fig. 5 is a configuration diagram of an electric water heater according to another embodiment, and Fig. 6 is a front view of the operation section and display section. 7 is a flowchart showing its operation, FIG. 8 is a configuration diagram of an electric water heater according to another embodiment, FIG. 9 is an electric circuit diagram thereof, and FIG. 10 is a flowchart showing its operation. Fig. 11 is a block diagram of a conventional electric water heater; Fig. 12 is a flow chart shown in Fig. 11.
The figure is its electrical circuit diagram, and FIG. 13 is its flowchart. 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, 70
71 is an energization time zone setting means, 71 is a manual reheating setting means,
72 is an upper heating element control device, 73 is a lower heating element control device, 100 is a remaining hot water amount detection means, and 101 is an automatic reheating setting means. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (3)

[Claims] (1) a hot water storage tank; a lower heating element placed at the bottom of the tank; an upper heating element placed in the middle of the tank; and a lower hot water temperature measuring means for measuring the hot water temperature in the tank; Upper water temperature measuring means for measuring the temperature of water heated by the heating element disposed in the middle of the tank; and energization time zone setting means for setting the time period during which the lower heating element and the upper heating element of the tank can be energized. a lower heating element control means for controlling the lower heating element based on information from the energization time period setting means and the lower hot water temperature measuring means; a manual reheating setting means for starting reheating by manual operation; An electric water heater characterized by comprising an upper heating element control means for controlling boiling of the upper heating element based on information from a temperature measuring means, a manual reheating setting means, and an energization time setting means. Boiling control device. (2) According to claim (1), the boiling control device of the electric water heater includes an automatic reheating setting means and a remaining hot water amount detecting means in place of the manual reheating setting means provided in the boiling control device of the electric water heater. Boiling control device for electric water heaters. (3) The boiling control device for an electric water heater according to claim (2), characterized in that the boiling control device for an electric water heater according to claim (2) is provided with manual reheating setting means. .