JPS6143617B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a hot water storage type water heater, and in particular changes the heat generating capacity of the heat generating device and the set temperature of the hot water according to the usage conditions to reduce heat loss due to natural heat radiation etc. and save power. This is what we are trying to do.

For example, push-up hot water storage type water heaters (hereinafter simply referred to as water heaters) that use late-night electricity when electricity consumption is cheaper have a fixed energization time, so they are not suitable for use in winter when hot water consumption is high. The heat generation capacity of the heat generating device is set so that the water temperature can be raised from 5 to 10 degrees Celsius to about 85 degrees Celsius within the energizing time.

However, the amount of hot water used is not necessarily the same every day, but varies depending on the day or season. For example, in summer when the amount of hot water used is low, more than half of the stored hot water often remains.

Therefore, in such a case, electricity starts all at once at midnight, and the water boils down in a short time. As a result, the power load is concentrated, and the original purpose of late-night power, which is to equalize the power load, cannot be achieved.
This also resulted in poor power transmission efficiency. In addition, boiling water in a short period of time means leaving unnecessarily high-temperature water unused for a long time. Heat loss due to heat radiation etc. increases.

The present invention was made in view of these drawbacks, and aims to eliminate the conventional drawbacks by changing the heat generation capacity of the heat generating device and the hot water temperature setting according to the usage conditions. .

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 shows the basic configuration of a push-up hot water storage type water heater that utilizes late-night electricity according to the present invention. 1st
In the figure, 1 is a hot water storage tank, 2 is a water supply port provided on the lower side of the hot water storage tank 1 and supplies water into the tank 1, and 3 is provided on the upper side of the hot water storage tank 1 and the hot water in the tank 1 is used for bathing, for example. A hot water supply port 4 for supplying hot water to the hot water storage tank 1 is a heat generating device installed below the center of the hot water storage tank 1, and has two heat generating elements inside thereof, namely a first heater 4a and a second heater 4b. Reference numeral 5 denotes a thermostat attached to the side of the hot water storage tank 1 between the water supply port 2 and the heat generating device 4 as a water supply temperature detection device, and is set to turn off at approximately 20° C. or higher. Thermostats 6 and 7 are installed on the side of the hot water storage tank 1 directly above the heat generating device 4, respectively, and serve as hot water temperature maintenance devices that turn on and off the first heater 4a based on the comparison between the set temperature and the detected temperature. 65℃ and thermostat 7 are set to turn off at approximately 85℃ or above. Reference numeral 8 denotes a thermostat as a residual hot water amount detection device attached to the approximately central side of the hot water storage tank 1, which detects the hot water temperature controlled by the hot water temperature holding device to ensure that the amount of residual hot water in the hot water storage tank 1 is less than half. Turns ON if the number is full, and turns OFF if the number is more than half.
For example, ON/OFF is set to occur at approximately 60°C.

The heat generating capacity control device, which is composed of these thermostats 5, 6, 7, 8, etc., and changes the setting of the heat generating capacity and hot water temperature of the heat generating device 4, has a circuit configuration as shown in FIG. In Figure 2, 9 is a power supply,
A relay coil 10 is connected in series with the thermostat 5 and is self-held by 11 relay contacts. 12 is the normally closed side contact 12a and the relay coil 1
It is a relay contact having a normally open side contact 12b which is closed by 0 excitation. The thermostat 6 is connected in series with the normally closed contact 12a of the relay contact 12, and the thermostat 7 is connected in series with the normally closed contact 12b of the relay contact 12.
connected in series with. Moreover, the first part of the heat generating device 4
The heater 4a is connected in series to the thermostats 6 and 7, respectively, and the second heater 4b is connected in series to the thermostats 6 and 7 via the thermostat 8, respectively.

The operation of the water heater configured as described above will be explained.

When the power supply 9 is automatically energized to the water heater by a time switch (not shown), the thermostat 5 for detecting the temperature of the water supply detects the temperature of the water supplied from the water supply port 2 to the lower part of the hot water storage tank 1. At this time, for example in summer, if the water temperature is about 20° C. or higher, the thermostat 5 is in the OFF state. Therefore, the relay coil 10 is not energized and the relay contact 12 is normally closed contact 1.
2a, the water temperature is controlled by the thermostat 6, and the set temperature is approximately 65°C.

On the other hand, if the water temperature is lower than 20°C, the thermostat 5 is in the ON state. Therefore, relay coil 1
0 is energized and the relay contact 12 is the normally closed contact 12a.
The contact 12b switches to the normally open side contact 12b, and the water temperature is controlled by the thermostat 7, and the set temperature is approximately 85
℃. In this way, heat loss can be reduced by changing the set temperature depending on, for example, winter or summer.

In each of the above cases, when the amount of hot water remaining in the hot water storage tank 1 is more than half, the hot water occupies the upper part of the hot water storage tank 1 than the lower part of the thermostat 8, so the thermostat 8 senses the hot water temperature and turns off.
state, only the first heater 4a is energized,
Since the heat generating capacity of the heat generating device 4 is reduced to approximately 1/2 to raise the temperature of the water, it is possible to prevent the water from boiling over in a short period of time. Further, when the amount of remaining hot water is less than half, the bottom surface of the hot water is located above the thermostat 8, so the thermostat 8 senses the water supply temperature and is in the ON state, so that the first and second heaters 4a are turned on. ,4
Both of b are energized. Therefore, the temperature of the hot water in the hot water storage tank 1 can be raised to the set temperature within the energization time.

The relay coil 10 excited by the thermostat 5 is self-held by the relay contact 11. As the temperature inside the hot water storage tank 1 increases from the ON state of the thermostat 5, the temperature at the bottom of the tank 1 rises to 20°C.
Even if the temperature rises above .degree. C. and turns off, the relay contact 11 remains closed, so the relay coil 10 remains energized and the set temperature remains at 85.degree. Note that the relay contact 11 is released when the time switch that sets the midnight energization time is turned off.

In this way, the hot water temperature in the hot water storage tank 1 can be changed between 65°C and 85°C according to the water supply temperature.
Further, the heat generating capacity of the heat generating device 4 can be changed depending on the amount of remaining hot water.

Note that the number of heaters may be more than two, and the heat generating capacity may be changed by varying the resistance value.
Further, the position and number of thermostats for detecting the amount of remaining hot water can be set arbitrarily. Although it is best to use late-night electricity with this hot water storage type water heater, it goes without saying that other types of electricity can also be used.

As explained above, according to the present invention, winter
The system is configured to detect changes in the water supply temperature during the summer and the amount of hot water remaining in the hot water storage tank, and change the set temperature of the hot water and the heat generating capacity of the heat generating device accordingly.
In the summer when the water temperature is high and the amount of hot water used is low, the boiling temperature can be kept low to reduce heat loss due to heat radiation from the water heater body, piping, etc. Furthermore, when there is a large amount of hot water remaining, the heat generating capacity of the heat generating device is reduced, so that it is possible to suppress the concentration of electric power load, thereby providing an extremely economical hot water storage type water heater.

[Brief explanation of the drawing]

FIG. 1 is a basic configuration diagram showing one embodiment of a hot water storage type water heater according to the present invention, and FIG. 2 is an electric circuit diagram of the same water heater. 1... Hot water storage tank, 4... Heat generating device, 5, 6,
7, 8...Thermostat, 10...Relay coil, 11, 12...Relay contact.

Claims (1)

[Claims] 1. In a hot water storage type water heater in which a heat generating device is provided in a hot water storage tank, the heat generating device is installed below the center of the tank, and its heat generating capacity is configured to be variable, while the tank between the water supply port and the heat generating device is installed below the center of the tank. The water supply water temperature detection device is attached to a side surface and detects the temperature of the water supplied into the hot water storage tank, and the remaining hot water amount detection means is attached to the substantially central side surface of the tank and detects the amount of hot water remaining in the hot water storage tank. Based on the detection signal from the water supply water temperature detection device, the heat generating device is controlled so that the low set temperature is set when the water supply water temperature is above a predetermined temperature, and the heat generating device is controlled so that the high set temperature is set when the water supply water temperature is lower than the predetermined temperature. A hot water temperature maintaining device is provided to control the device, and the heat generating capacity is controlled to be small when the remaining hot water amount is above a predetermined amount based on a detection signal from the remaining hot water amount detection means, and is increased when the remaining hot water amount is less than the predetermined amount. A hot water storage type water heater characterized by being equipped with a heat generation capacity control device that controls the heat generation capacity.