JPS5875658A - Hot water storage type electric water heater - Google Patents

Abstract

PURPOSE:To contrive to save energy by a system wherein the proper capacity of heating element is calculated based upon the hot water quantity intended to be used the following day, state of remaining hot water and the like in order to heat-up said hot water quantity with constant midnight power. CONSTITUTION:The hot water quantity, which is stored in a hot water storage tank and is intended to be used the following day, is inputted to a hot water quantity setting unit 4 and an arithmetic unit 6 calculates the thermal calorie to be stored in the hot water storage tank based upon the detected value of a feed water temperature sensor 5 just after the entry of midnight power supply time zone and of a remaining hot water quantity sensor 7 and further of a remaining hot water temperature sensor 8. In addition, an arithmetic unit 9 calculates the thermal calorie of hot water remaining in the hot water storage tank. Furthermore, an arithmetic unit 10 calculates the required capacity of heating element based upon the net thermal calorie to be applied. As a next step, a power controlling unit 11 applies the predetermined electric energy throughout the entire midnight power energizing time zone so as to finish the heating-up of the hot water quantity intended to be used the following day simultaneously with the end of the power supply time zone. In such a manner as described above, the concentration of the power loads is relieved and consequently radiation losses are reduced.

Description

[Detailed Description of the Invention] This invention relates to a hot water storage type electric water heater, which calculates an appropriate heating element capacity from the amount of hot water used, the water supply temperature, and the state of the remaining hot water in the hot water tank, and always boils the water in a fixed amount of time. It is intended to do so.

The main electrical circuit of a conventional hot water storage type electric water heater is shown in Figure 1. In the figure, 1 is the power supply, 2 is the heating element, and 3
is an automatic temperature controller.

Next, to explain the operation using the general late-night power supply as an example, the book heating element 2 boils water at around 8υ, which corresponds to the water temperature in winter, to about 85υ during the late-night power supply time. The heating element capacity is set accordingly. In addition, the self-made temperature regulator 3 has a normally closed contact, and is configured to open the contact and stop supplying electricity to the heating element 2 when the water in the hot water storage tank reaches 85°C. The interior is filled with 85 υ of hot water every morning.

However, the amount of hot water used is not always the same.

The days vary greatly depending on the season. In particular, whether or not a person takes a bath is a factor that greatly influences the amount of hot water used, and on days when a person does not take a bath, more than half of the stored hot water may remain.

Therefore, if there is any remaining hot water, the electricity will start flowing all at once at midnight and the water will boil in a short time. As a result, the power load is concentrated, making it impossible to equalize the power load, which is the original purpose of late-night generation, and resulting in poor power transmission efficiency. l
This invention attempts to eliminate these conventional drawbacks, such as increasing heat loss due to natural heat dissipation from the hot water storage tank and heat dissipation of hot water stagnant in the pipes. The amount of hot water used for the next day is set in advance.

The appropriate heating element capacity is calculated from the water supply temperature and the state of the remaining hot water in the hot water storage tank, and the entire late-night power supply time is used to heat the water at a constant power level.

The present invention will be explained below based on the energization control block diagram shown in FIG. In FIG. 2, 4 is a hot water amount setting device for presetting the amount of hot water to be used the next day stored in the hot water storage tank;
5 is a water supply temperature sensor that detects the temperature of water supplied to the hot water storage tank; 6 is a sensor that detects the amount of hot water to be stored in the hot water storage tank based on the set value set by the hot water amount setting device 4 and the water supply temperature detected by the water supply temperature sensor 5; This is a computing device that calculates heat calories.

T is a remaining hot water amount sensor for detecting the amount of hot water remaining in the hot water storage tank, 8 is a remaining hot water temperature sensor for similarly detecting the temperature of remaining hot water in the hot water storage tank, and 9 is each of the above-mentioned sensors 5. T
, 10 is a calculator B for calculating the remaining hot water thermal calories from the water supply temperature, the remaining hot water amount, and the remaining hot water temperature detected by , 8.
is a computing unit C for calculating the required heating element capacity from the difference in thermal calories obtained by the above-mentioned computing unit 456 and computing unit B9,
Reference numeral 11 denotes a power control device that controls energization to the heating element so that the required heating element capacity calculated by the calculator C is obtained.

Next, an example of the operation of the configuration described in item 1 will be explained using symbols and formulas. First, the amount of hot water stored in the hot water storage tank to be used the next day is set as V+)t2 (hot water temperature 'l't'o), and this is input to the hot water setting device 4, and the temperature of the water supply immediately after entering the late night energization period is determined. If the detected value of the sensor 5 is to, the detected value of the remaining hot water amount sensor 7 is malliter, and the detected value of the remaining hot water temperature sensor 8 is 2υ, then the computing unit Muro calculates (Tl - t) x V, and it is late at night. 'Thermal power that should be stored in the hot water storage tank by the end of the power supply time!J -Kx
(K1= (Tt-t) xV) Exit. In addition, the calculator B9 calculates (T2-t)x+, and adds 2 (
K2 = (T2-t) , the required heating element capacity CKw) is calculated from the net heat calories to be applied, which is obtained by subtracting the heat calories for the remaining hot water by % from the heat calories Kl to be stored in the hot water storage tank (+KWH=8soKg). Next, the arithmetic unit cI
When the required heating element capacity (KW) is calculated using LIKj, the power control device #
At t11, the amount of electricity applied to the heating element is controlled, and a predetermined amount of electricity is added throughout the late-night power supply period, and the boiling is controlled to end at the same time as the late-night power supply time ends.

Therefore, the greater the amount of remaining hot water in the hot water storage tank and the higher the temperature of the remaining hot water, the less electricity is required for the heating element, and the electricity is always averaged over the entire late-night power supply period, so the electricity load The concentration of hot water is alleviated, and high temperature hot water is not left in the hot water storage tank for a long time, so heat radiation loss can be reduced.

In the above operation example, the case where the boiler is used late at night has been explained, but the same effect can be obtained by providing a timer mechanism that allows input of the desired boiling time for general use.

As described above, this invention provides the amount of used water i stored in the hot water storage tank.
No need to set t in advance! a setting means, a water supply temperature detection means for detecting the temperature of the water supplied to the hot water storage tank, and a set value set by the hot water amount setting means and the water supply temperature detected by the water supply temperature detection means to determine the thermal calories of the hot water to be stored. a calculation means for calculating the amount of hot water remaining in the hot water storage tank; a residual hot water temperature detection means for detecting the temperature of the remaining hot water in the hot water storage tank; , calculation means B for calculating the remaining hot water thermal calories from the remaining hot water amount, the remaining hot water temperature, etc.

a calculation means C that calculates the required heating element capacity from the difference between the calculation means M and the calculation means B; and a control means that controls the passage 1 to the heating element so that the required heating element capacity calculated by the calculation means C is added. It detects the water supply temperature to the hot water storage tank, the amount of hot water remaining, and the lA hot water temperature to calculate the required heat calories.
Since the power is applied evenly over the power-on time period, and only the amount of heat calories required for the hot water supply is needed (l:to+t+c,i), the power load is equalized to 110T capacity, and the power transmission is Increased efficiency. In addition, the amount of hot water left each day is reduced and hot water is no longer left unused for long periods of time, reducing heat loss in each building and reducing maintenance costs.

[Brief explanation of the drawing]

Figure 1 shows the main electrical circuit diagram of a conventional hot water storage type electric water heater, and Figure 2 shows a control block diagram of the present invention. 4 is a hot water amount setting device, and 5 is a water supply temperature sensor. Reference numeral 6 indicates a computing unit, 7 indicates a remaining hot water amount sensor, 8 indicates a remaining hot water temperature sensor, 9 indicates a computing unit B, and 10 indicates a power control device C911. Agent Shin Kuzuno - (16 out of 16)

Claims (1)

[Scope of Claims] Hot water amount setting means for presetting the amount of hot water to be used and stored in a hot water storage tank, a water supply temperature detection means for detecting the temperature of water supplied to the hot water storage tank, and a set value set by the hot water amount setting means. A calculation means for calculating the thermal calories of the amount of hot water to be stored from the water supply temperature detected by the water supply temperature detection means, and a remaining hot water amount detection means for detecting the amount of hot water remaining in the hot water storage tank. a remaining hot water temperature detection means for detecting the temperature of the remaining hot water in the hot water storage tank, the supply water temperature and the amount of remaining hot water detected by each of the detection means;
a calculation means B that calculates the remaining water calorie from the residual water temperature; a calculation means C that calculates the required heating element capacity t from the difference between the calculation means and the calculation means B; and the required heating element calculated by the calculation means C. A hot water storage type electric water heater comprising: power control means for controlling energization to a heating element so as to increase capacity.