JPS624621B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a hot water storage type water heater, and particularly aims to reduce heat loss due to natural heat radiation and save power by changing the heat generating capacity of the heat generating device according to usage conditions. .

For example, in 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, the power-on time is kept constant.
To suit the winter conditions when hot water consumption is high, the heating capacity of the heating device is set so that the water temperature can be raised from 5° to 10°C to about 85°C within the time the electricity is on.

However, the amount of hot water used is not always the same and varies depending on the day or season. For example, in the 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 has been made in view of these drawbacks.
The purpose of this invention is to overcome the drawbacks of the conventional device by changing the heat generating capacity of the heat generating device according to 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 heating elements inside, namely a first heater 4a and a second heater 4b. 5
is 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 water temperature detection device, and is set to turn off at approximately 20°C or higher. 6 is a thermostat that is attached to the side of the hot water storage tank 1 directly above the heat generating device 4 and serves as a hot water temperature maintenance device that turns the first heater 4a on and off based on the comparison between the set temperature and the detected temperature. It is set. Reference numeral 7 denotes a thermostat as a residual hot water amount detection device attached to the side surface above the approximate center of the hot water storage tank 1, and by detecting the hot water temperature controlled by the hot water temperature holding device, the amount of remaining hot water in the hot water storage tank 1 is reduced by half. If there are only the following
ON, and OFF if more than half is present. ON・
For example, OFF is set to occur at a temperature of approximately 80°C.

A heat generating capacity control device which is constituted by these thermostats 5, 6, 7, etc. and changes the heat generating capacity of the heat generating device 4 has a circuit configuration as shown in FIG. In Figure 2, 8 indicates the respective thermostats 5,
A power supply 6 and 7 are connected in series, and 9 is a relay coil connected in series with the thermostat 5, which is self-maintained by 10 relay contacts. 11 is a relay contact connected in series with the thermostat 7. The first heater 4a of the heat generating device 4 is connected in series to the thermostat 6, and the second heater 4b
is connected in series to the thermostat 7.

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

When the power supply 8 is automatically energized to the water heater by a time switch (not shown), the temperature of the water supplied from the water supply port 2 to the lower part of the hot water storage tank 1 is detected by the thermostat 5 for detecting the temperature of the supplied water. 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 9 is not excited and the relay contact 11 remains open, the second heater 4b connected to the thermostat 7 is not energized, and only the first heater 4a connected to the thermostat 6 is energized. In this way, when the water supply temperature is high, the heat generating capacity of the heat generating device 4 is approximately 1/2
This allows the water temperature to be raised over time during the energization period, and there is no need to leave hot water unnecessarily. When the water temperature rises to the set temperature of approximately 85°C, the thermostat 6 is activated and the first heater 4a is turned on until the power supply 8 is turned off.
Turn it on and off to keep the water temperature constant.

On the other hand, if the water temperature is lower than 20°C, the thermostat 5 is in the ON state. Therefore, relay coil 9
is excited and the relay contact 11 is closed, so that the second heater 4b can be energized. In this case, 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 7, so the thermostat 7 senses the hot water temperature and is in the OFF state. Therefore, only the first heater 4a is energized and the heat generating capacity of the heat generating device 4 is reduced to approximately 1/2 to raise the temperature of the water, thereby preventing 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 7, so the thermostat 7 senses the water supply temperature and is in the ON state, so that the first and second heaters 4a, 4b are both energized. Therefore, the temperature of the hot water in the hot water storage tank 1 can be raised to the set temperature of 85° C. within the energization time. In this way, when the water supply temperature is lower than the predetermined temperature, the heat generating capacity of the heat generating device 4 changes depending on the amount of remaining hot water.

Here, the relay coil 9 excited by the thermostat 5 is self-held by the relay contact 10, and when the thermostat 5 is turned on, the lower temperature rises to below 20°C due to the temperature rise in the hot water storage tank 1, and the thermostat 5 is turned off. Even in this state, the relay contact 10 remains closed and the relay coil 9 remains energized, making it possible to energize the second heater 4b. This relay contact 10 is released when the time switch that sets the midnight energization time is turned off.

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, the change in water supply temperature in winter and summer and the amount of hot water remaining in the hot water storage tank are automatically detected and the heat generating capacity of the heat generating device is changed accordingly. It is possible to suppress the concentration of load, and since there is almost no need to leave hot water unattended when it is not needed, it is possible to provide an extremely economical hot water storage type water heater in which heat loss is extremely reduced.

[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...
Thermostat, 9...Relay coil, 10, 11
...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 side surface of the tank between the water inlet and the heat generating device is configured to be variable. a water supply temperature detection device that is attached to the hot water storage tank and detects the temperature of the water supplied to the hot water storage tank; a residual hot water amount detection device that is attached to the side surface above approximately the center 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 temperature detection device, the heat generation capacity is controlled to be small when the water supply temperature is above a predetermined temperature, and the water supply water temperature is lower than the predetermined temperature based on the detection signals from the water supply temperature detection device and the remaining hot water amount detection device. A hot water storage type water heater characterized by being provided with a heat generating capacity control device that controls the heat generating capacity to be small when the amount of remaining hot water is large and to be large when the amount of remaining hot water is small.