JPS6220466B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to temperature control for water heaters that use gas, oil, electricity, etc. as heat sources, and is intended to control the amount of water supplied in order to solve the conventional problem of not being able to obtain the desired hot water temperature when overloaded. The present invention aims to provide a new control device that supplies the amount of hot water desired by the user using a newly installed total water supply amount setting device, and displays the remaining time until the total amount of hot water supplied by the setting device is reached.

The explanation will be given below using a gas water heater as an example.

FIG. 5 is a configuration diagram of a conventional gas water heater, in which combustion heat from a burner 1 serving as a heat source and water are exchanged with a heat exchanger 2 to provide hot water. In the temperature control device 3,
The signal (TWO) from the hot water temperature detector 4 and the signal (TWR) from the hot water temperature setting device 5 are input, a predetermined combustion amount is determined from the deviation (TER = TWR - TWO), and the supplied heat amount controller 6 Temperature control was carried out by controlling the Here, a thermistor is often used as the hot water temperature detector 4, and a PiD method is often used for temperature control. In the figure, 7 indicates a hot water supply unit, and 8 indicates a container such as a bathtub.

Figure 4 shows the amount of hot water supplied by a gas water heater W and the temperature rise Δ
It is a figure showing the relationship with T. The thick solid line in the figure shows the characteristics at maximum combustion Qg _nax , that is, the capacity curve of the water heater. In other words, the maximum combustion amount Qg _nax , the temperature rise ΔT, and the flow rate W which is the load are as follows, where η is the combustion efficiency, η・Qg _nax = W・ΔT ...(1), and ΔT=η・Qg _nax / W...(2) Therefore, there is no temperature rise beyond that indicated by the thick solid line in FIG. For example, if the amount of hot water discharged is W ₁ when the maximum combustion amount is Qg _nax , the temperature rise will be ΔT ₁ as shown in the figure. The above-mentioned temperature control device 3 controls the set value by the hot water temperature setting device 5.
When the difference between TWR and the incoming water temperature TWi, that is, the temperature increase value ΔT, is ΔT ₁ , it acts effectively in the region of the hot water output amount WW ₁ . However, if W>W ₁ , control becomes impossible, and the hot water temperature TWO will never reach the set temperature TWR no matter how long it takes.

In this way, the maximum combustion amount Qg _nax limits the amount W of hot water that can be controlled at the outlet temperature. When using a conventional water heater like this to pour hot water into a bathtub, etc., either adjust the amount of hot water in the hot water supply section at the beginning of use to obtain hot water at the desired temperature, or set it to a high value to increase the amount of hot water supplied. They had no choice but to use cumbersome methods such as squeezing the water and mixing it with water. In addition, it was necessary to estimate the total amount of hot water required based on experience, or to use a water flow detector using a reed switch or the like.

The present invention provides a control device that eliminates the drawbacks found in the conventional water temperature control of water heaters, and allows hot water at the desired set temperature to be always obtained, as well as to adjust the signal of the total water supply amount setting device. Therefore, the desired amount of hot water is supplied, and the time required to reach the value set by the total water amount setting device is calculated and displayed.

FIG. 1 is a configuration diagram of a gas water heater of the present invention. Devices with the same numbers as in FIG. 5 are devices having the same functions. The control device 9 takes in the signal from the hot water temperature detector 4, the signals from the hot water temperature setting device 5, and the total water supply amount setting device 10, and controls the amount of heat supplied to the controller 6, the amount of water supplied to the controller 11, and the display 12. It is outputting a signal.

With reference to FIG. 2, the operation of the control device 9 of FIG. 1 will be explained. Inside the control device 9, there are a main calculation control section 9A and a buffer section 9B that takes in signals from the hot water temperature detector 4.
, buffer sections 9C and 9D that take in signals from the setting devices 5 and 10, and buffer sections 9E, 9F, and 9G that drive the supply heat amount controller 6, the supply water amount controller 11, and the display 12, respectively.
It consists of The amount of water supplied depends on the temperature deviation mentioned above.
The sequence is set so that the maximum flow rate is obtained when the water heater is first used, and when the TER remains even after the hot water temperature control reaches a steady state, the supplied water amount is reduced to zero. Operate the controls. As is clear from Figure 4, when the amount of water supplied decreases, the temperature rise value due to the capacity of the water heater increases,
It becomes possible to control the set temperature.

In addition, in Figure 1, the hot water temperature detector 4 is a one-sensor type that is attached only to the hot water outlet side, and the water supply temperature can be covered by memorizing the detected temperature at the beginning of the water supply, but may be provided. The difference between the water supply temperature signal (TWi) obtained in this way and the signal (TWR) of the hot water temperature setting device 5, ΔT=TWR−TWi...(3), is calculated based on the water heater's capacity curve. For example, you can know the current amount of hot water. In other words, the deviation
If the set temperature is obtained when the TER is throttled down to zero, then if the maximum combustion amount is Qg _nax , then the flow rate W on the capacity curve is the current hot water output (unit:
/min etc.). Moreover, if it is X% of the maximum combustion amount, it is possible to know the current flow rate from the value of X and the characteristics shown in FIG. 4 according to the ΔT.

Therefore, by integrating the flow rate obtained as described above, and subtracting the integrated value of hot water supply amount from the time of ignition to the present from the signal of the total water supply amount setting device, and dividing by the current flow rate, the set hot water supply amount is calculated. You can find the remaining time until reaching . Displaying this remaining time on a display as shown in FIG. 3 will definitely improve convenience for the user. For example, A is a bar display and B is a digital display.

In addition, usability can be improved by using a method such as notifying the user of the termination using a buzzer or other warning means or stopping hot water supply and combustion when the total amount of hot water supply reaches a set value. Of course.

By the way, in the above explanation, the remaining time until the set total water supply amount is reached using the current instantaneous amount of hot water supply, but the total amount of hot water supplied from the total water supply amount setting device,
Considering the product of the temperature increase value obtained from the hot water temperature setting device signal and the water supply temperature signal, that is, the total amount of heat to be supplied, performs hot water temperature control and water amount control to eliminate deviations, and integrates the amount of supplied heat. Even in the method of checking the match with the set value, the remaining time can be calculated by dividing the amount of residual heat by the instantaneous amount of heat currently being supplied.

As is clear from the above explanation, according to the water heater control device of the present invention, the amount of hot water dispensed is always limited to the range where the set hot water temperature can be controlled, so the user can always obtain hot water at the desired temperature. In addition to this excellent effect, it is possible to store a desired amount of hot water that is effective for bathing, etc., and the remaining time until the set hot water supply amount is reached is displayed, greatly improving usability.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a gas water heater showing an embodiment of the present invention, Fig. 2 is a block diagram showing a control device of the invention, and Fig. 3 is a diagram of a display device showing an embodiment of the invention. FIG. 4 is a capacity characteristic diagram of a water heater, and FIG. 5 is a configuration diagram of a conventional gas water heater. 1... heat source, 2... heat exchanger, 4... hot water temperature detector, 5... hot water temperature setting device, 6... supply heat amount controller,
9...Control device, 10...Total supply water amount setting device, 1
1... Supply water amount controller, 12... Display device.

Claims (1)

[Claims] 1. Equipped with at least a heat source, a heat exchanger, a supply heat amount controller, a hot water temperature setting device, a hot water temperature detector, a supply water amount controller, a total supply water amount setting device, and an indicator, The supplied heat amount controller is controlled to increase or decrease the amount of heat supplied to the heat source depending on the deviation TER between the signal of the hot water temperature setting device and the signal of the hot water temperature detector,
Controls the water supply amount controller to increase or decrease the amount of hot water depending on the signal from the TER and the total water supply amount setting device, and calculates the remaining time until the total amount of hot water reaches the value of the total water amount setting device. A control device for a water heater that displays information on the display.