JP2689288B2 - Heating controller for water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating control device for a water heater, and more particularly to a heating control device for a water heater capable of boiling water in a tank without excess or deficiency during the daytime. is there.

[0002]

2. Description of the Related Art FIG. 4 is a schematic diagram showing an example of a conventional controller for an electric water heater. This electric water heater heating control device can heat by day-time power regardless of whether it is daytime or nighttime, and it is boiled up during the daytime when the amount of hot water is not enough for boiling during the nighttime. Is. In the figure, 1 is a tank for storing hot water, and 2 is a heating element for heating the water in the tank 1. Reference numeral 3 is an electromagnetic relay for turning on / off the power supply to the heating element 2, and reference numeral 4 is a power source for the heating element. Reference numeral 5 is a hot water temperature detection sensor for measuring the hot water temperature in the tank 1 heated by the heating element 2, and 7 is a residual hot water detection sensor for detecting the residual hot water amount in the tank 1. 8a is an electromagnetic relay 3 based on the hot water temperature detected by the hot water temperature sensor 5.
Is a heating element control circuit for heating the hot water in the tank 1 by controlling the electric current to the heating element 2. Reference numeral 9 is a water supply pipe for supplying water into the tank 1, and 10 is a hot water supply pipe for collecting hot water in the tank 1.

Next, the operation of the conventional heating controller for the water heater constructed as described above will be described. It is assumed that all the hot water in the tank 1 is boiling during the nighttime hours, and here, the boiling during the daytime hours will be described. When hot water is taken from the hot water supply pipe 10 to use hot water, the same amount of water as the hot water taken is supplied from the water supply pipe 9 into the tank 1.
In the tank 1, hot water and water are separated due to the difference in specific gravity. The hot water is located in the upper part of the tank 1 and the water is located in the lower part of the tank 1. When the amount of hot water collected in this way reaches a certain amount, the position of the remaining hot water detection sensor 7 becomes water, and the hot water temperature detected by the remaining hot water detection sensor 7 rapidly decreases. When the remaining hot water detection sensor 7 detects the change in the detected hot water temperature, the electromagnetic relay 3 is turned on by the command of the heating element control circuit 8a, the heating element 2 is energized, and the water in the tank 1 is heated. At this time, by appropriately selecting the position of the residual hot water detection sensor 7, it is possible to heat only the water below the residual hot water detection sensor 7 without affecting the hot water above the residual hot water detection sensor 7. That is, it is possible to boil only the water up to the residual hot water detection sensor 7 by boiling once. Therefore, by performing this boiling a number of times corresponding to the shortage of boiling at night, the required amount of hot water can be boiled during the daytime without excess or deficiency.

Further, there is an invention disclosed in Japanese Patent Application Laid-Open No. 61-70338 as a water heater in which water in a tank is boiled regardless of whether it is day or night by electric power for each time zone. According to the present invention, two heating elements are provided, and when the heating of the first heating element is insufficient for the required heat amount, the second heating element is used.
The heating element is energized to obtain the required amount of heat.
The first heating element can be boiled only during the midnight power supply time zone, and the second heating element can be boiled at any time regardless of the time zone.

[0005]

In the conventional heating control device for the water heater constructed as described above, a dedicated residual hot water detection sensor 7 must be provided in order to detect a fixed amount of hot water. There was a problem that the cost of the Further, when hot water is taken during boiling, the amount of hot water taken is also boiled, so that the boiling amount per one time is large, and there is a problem that boiling is performed more than necessary.

On the other hand, the water heater disclosed in Japanese Patent Laid-Open No. 61-70338 requires two heating elements, a first heating element and a second heating element, and further has an upper temperature detecting means and a lower temperature. There is a problem that the structure is complicated and expensive, such as requiring two temperature detecting means as the detecting means.

The present invention has been made in order to solve the above-mentioned problems. One heating element and one hot water temperature are provided without providing a dedicated sensor for detecting a fixed amount of hot water. An object of the present invention is to obtain a heating control device for a water heater that can perform boiling without excess or deficiency during the daytime by using only the detection sensor.

[0008]

A heating control device for a water heater according to the present invention comprises a tank for storing hot water, a heating element for heating water in the tank, and a hot water temperature heated by the heating element. And one hot water temperature detecting means for measuring the supply water temperature, a boiling amount setting means for setting a required boiling amount, and a boiling amount during the daytime by subtracting the night boiling amount from the required boiling amount. Calculate the amount that does not occur, and also calculate the boiling water temperature, based on the difference between the boiling water temperature and the water supply water temperature, the amount that must be boiled during the daytime period, and the amount of heat generated by the heating element. Heating control required for boiling water
Calculating means for calculating the time , heating element control means for controlling one heating element regardless of the time zone based on the signal from the hot water temperature detecting means, and interlocking with the control of the heating element, in the daytime hour Equipped with an energization time measuring means for measuring the energization time to each heating element, when the required boiling amount set by the boiling amount setting means is larger than the night boiling amount, the calculating means generates heat during the daytime When the water temperature in the tank rises to the boiling water temperature due to the heating of the heating element, the body control means is controlled to stop the energization of the heating element and the energization time is compared with the heating control time. When it is determined that the temperature exceeds the limit, the heating element control means ends the heating control.

[0009]

[Operation] The calculating means calculates the amount that must be boiled during the daytime from the difference between the required boiling amount set by the boiling amount setting means and the night boiling amount, and also calculates the boiling water temperature. Then, the temperature difference between the boiling water temperature and the feed water temperature,
Based on the amount of heat that must be boiled during the daytime and the amount of heat generated by the heating element, it is necessary to boil during the daytime.
Calculate the heating control time . The energization time measuring means measures the time during which the heating element is energized during the daytime. When the required boiling amount set by the boiling amount setting means is larger than the night boiling amount, the calculation means causes the heating element control means to control heating during the daytime, and the heating element heats the water temperature in the tank to boil. After raising the water becomes warm compares the current time and the heating control time, determines that the current time has exceeded the heating control time,
The heating element control means ends the heating control.

[0010]

FIG. 1 is a schematic view showing an embodiment of the present invention.
It should be noted that the same or corresponding parts as those in the conventional example of FIG. Reference numeral 2 is one heating element that can be used in both daytime and nighttime for heating the water in the tank 1, and 5 is a hot water temperature detection sensor for measuring both the hot water temperature and the supplied water temperature which are heated by the heating element 2. . 6 is an energization time measuring circuit for measuring the time when the heating element 2 is energized, 8 is an electromagnetic relay 3 controlled by signals from the energization time measuring circuit 6 and the hot water temperature detection sensor 5, and the energization to the heating element 2 is controlled. It is a heating element control circuit.

FIG. 2 is a block diagram of an embodiment of the energization time measuring circuit 6 and the heating element control circuit 8. In the heating element control circuit 8, 11 is a boiling amount setting device for setting the boiling amount, 12 is an analog multiplexer for selecting the hot water temperature detected by the hot water temperature detection sensor 5 and the signal from the boiling amount setting device 11, 13 is an A / D converter for converting the input signal from the analog multiplexer 12 into a digital signal, 14
Is a CPU for performing various processes, and 15 is a storage device for operating the CPU 14. A buffer circuit 19 turns ON / OFF the electromagnetic relay 3 based on a command from the CPU 14, and a resistor 20 is connected in series with the hot water temperature detection sensor 5.

In the energization time measuring circuit 6, 16 is a reference clock generating circuit for generating a pulse signal serving as a reference for measuring the energizing time, and 17 is a reference clock generating circuit 1.
An analog switch that opens and closes the output signal of 6 on the basis of a command from the CPU 14, and 18 is an energization time counter that counts the pulse signal from the reference clock generation circuit 16 sent through the analog switch 17 and measures the energization time. .

Next, the operation of the present invention configured as described above will be described with reference to the flowchart of FIG. First,
At the end of night-time boiling (step S-1), the energization time counter 18 that measures the number of hours energized during the daytime is cleared (step S-2). At this time, it is assumed that all the hot water in the tank 1 is boiling. Next, from the required boiling amount set by the boiling amount setting means 11,
The amount Q that must be boiled during the daytime is calculated by subtracting the nighttime boiling amount, and the boiling water temperature Ta is set from that amount and the feed water temperature (step S-3). At this time, if there is no amount that needs to be boiled during the daytime, the process ends as it is, and if there is an amount that must be boiled during the daytime (step S-4), the amount of boiling and boiling setting The number of hours Hd required for energization is calculated based on the temperature difference between the hot water temperature and the supplied water temperature and the amount of heat generated per hour by the heating element (step S-5).

When the hot water in the tank 1 is taken, the hot water temperature Tm detected by the hot water temperature detecting sensor 5 is lowered. The detected hot water temperature Tm is compared with the hot water temperature Tb slightly lower than the boiling hot water temperature Ta (step S-7), and the hot water temperature sensor 5 is detected.
If the detected hot water temperature Tm is lower than Tb, the CPU 14 energizes the heating element 2 by turning on the electromagnetic relay 3 through the buffer 19 (step S-8) to heat the hot water in the tank 1. At this time, a signal for opening the analog switch 17 is output at the same time, and a signal from the reference clock generation circuit 16 is input to the energization time counter 18 while the heating element 2 is energized, so that the energization time for the heating element 2 is changed. Count (step S-9). During this time, the detected hot water temperature Tm of the hot water temperature detection sensor 5 and the boiling set hot water temperature Ta are compared (step S-10), and when the detected hot water temperature Tm becomes equal to or higher than the boiling hot water set temperature Ta, the heating element 2 is moved. Is stopped (step S-11), and at the same time, the counting of the energization time counter 18 is stopped. Next, the required number of energized hours that must be energized during the daytime is compared with the number of hours measured by the energized time counter (step S-6), and the same is performed until the number of energized times becomes equal to or greater than the required number of energized hours Repeat the operation,
When the number of energized hours exceeds the required number of energized hours, the procedure ends.

Further, in the present invention, even if the number of energizing times during the energization of the heating element 2 exceeds the required number of energizing times,
If the hot water temperature Tm detected by the hot water temperature sensor 5 does not exceed the boiling set hot water temperature Ta, the heating element 2 is not energized. Therefore, the hot water heating element 2 is turned on before the boiling set hot water temperature Ta is reached. Is not stopped, and it will always boil up to the set boiling water temperature Ta.

In the above description, an electric heater is used as the heat source for heating the hot water in the tank, but other heat sources such as oil and gas may be used. At this time, the heating element serves as a boiler device, the electromagnetic relay serves as a valve device for adjusting the supply to the boiler, and the power source for the heating element serves as a supply source of oil, gas and the like. Also, the ON-OF of the heating element
Although an example in which an electromagnetic relay is used is shown in F, this may be any element that can turn on / off the electric path of the heating element, and for example, a semiconductor switch (thyristor, triac) may be used. In addition, the heating element control circuit has a CPU
Although a (microcomputer) is used, an operational amplifier or the like may be used.

Further, the energization time measuring circuit counts the reference clock by turning it on and off by the gate of the analog switch, but it can be realized by the logic in the microprocessor, or by the D / A converter, the charging circuit. It can also be realized in an analog manner by using a discharge circuit, an operational amplifier or the like. Furthermore, as the means for generating the reference clock,
An oscillator circuit may be formed using a crystal oscillator, a ceramic oscillator, or the like, or may be created by a microcomputer by S / W interrupt or the like, or may be created from a commercial frequency.

As the hot water temperature detecting sensor, any element capable of converting a temperature signal into an electric signal can be used, and examples thereof include a thermistor, a posistor, a thermocouple, and a bimetal. The boiling amount setting means may be a variable resistor or any device capable of giving a signal from the outside, such as a keyboard. Further, even if it is not a substance, for example, it is necessary to input the boiling amount data set by the boiling amount setting means and the boiling amount data in the night time zone to boil in the daytime zone. You may make it calculate the amount and boiling setting hot water temperature. Further, it is possible to input the data of the supply water temperature and the data of the heat generation amount of the heating element per hour, and calculate the necessary time of the daytime zone.

[0019]

As described above, according to the present invention, since the heating element control means capable of controlling the heating element is used in both the daytime and nighttime zones, heating is performed by one heating element in both the daytime and nighttime zones. be able to. Also, the calculation means converts the boiling amount that must be boiled in the daytime zone into heat quantity, calculates the boiling time in the daytime zone, and controls the boiling amount in the daytime zone based on the boiling time. Therefore, it is not necessary to control the amount of remaining hot water, that is, the amount of supplied water, and therefore it is not necessary to provide a dedicated sensor for detecting the amount of remaining hot water. Therefore, the number of constituent means is reduced and the product price can be reduced. Further, since the upper limit is set according to time, it is economical because boiling is not performed more than necessary amount. Further, since the hot water temperature control is prioritized over the time control, for example, there is an error in the calculation of the amount of heat required for boiling by not providing the sensor for detecting the remaining hot water amount described above,
Even if there is an error in the calculation of the heating control time required for boiling during the daytime, when the temperature of the hot water is low, the heating is not stopped and the water is boiled until it reaches the boiling water temperature. Since the temperature is raised, it is possible to perform efficient control without terminating the operation while the hot water temperature remains low.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of the present invention.

FIG. 2 is a block diagram of an embodiment of heating time measuring means and heating element control means, which are essential parts of the present invention.

FIG. 3 is a flowchart for explaining the operation of the present invention.

FIG. 4 is a schematic diagram showing an example of a conventional heating control device for a water heater.

[Explanation of symbols]

 1 Tank 2 Heating Element 3 Electromagnetic Relay 5 Hot Water Temperature Sensor 6 Passage Time Measuring Circuit 8 Heating Element Control Circuit 11 Boiling Amount Setting Device 12 Analog Multiplexer 13 A / D Converter 14 CPU 15 Storage Device 16 Reference Clock Generation Circuit 17 Analog Switch 18 energizing time counter

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP 60-134138 (JP, A) JP 60-134142 (JP, A) JP 4-64862 (JP, A) JP 4- 86454 (JP, A)

Claims (1)

(57) [Claims] 1. A tank for storing hot water, one heating element for heating water in the tank, and one hot water temperature detecting means for measuring the hot water temperature and the supplied water temperature heated by the heating element. , A boiling amount setting means for setting the required boiling amount, and subtracting the night boiling amount from the required boiling amount to calculate the amount that must be boiled during the daytime, and also calculate the boiling water temperature. Then, based on the difference between the boiling water temperature and the feed water temperature, the amount of heat that must be boiled during the daytime period and the amount of heat generated by the heating element, the heating control time required for boiling during the daytime period A heating means control means for controlling the one heating element regardless of the time zone based on a signal from the hot water temperature detecting means; and a daytime time zone in conjunction with the control of the heating element. 1 in
An energization time measuring means for measuring the energization time to each heating element is provided, and when the required boiling amount set by the boiling amount setting means is larger than the nighttime boiling amount, the calculating means is in the daytime zone. the heating element control means causes the heating control is, the said energization time by stopping the energization of the water temperature in the tank by heating of the heating element is boiling and becomes hot water temperature to the heating element to
Compared with the heating control time , the energizing time is the heating control
A heating control device for a water heater, characterized in that when it is judged that the time has passed, the heating element control means ends the heating control.