JPH0371620B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a bath water level setting method for automatically filling a bathtub with hot water of a desired temperature up to a predetermined water level.

[Conventional technology]

FIG. 3 is a block diagram showing a conventional automatic bath system that automatically fills a bathtub with hot water at a desired temperature up to a predetermined water level. In FIG. 2, 1 is a bathtub, 2 is a water level switch, 3 is a thermistor, and 4 is a A combustor, 5 a breaker, and 6 a controller.

The controller 6 controls the combustor 4 so that the water temperature in the bathtub 1 reaches a desired temperature based on the water temperature detection signal from the thermistor 3, and controls the water level switch 2.
When receiving a signal that the hot water in the bathtub 1 has reached the set amount, the water valve 5 is closed. Thereby, a set amount of hot water at a desired temperature is stored in the bathtub 1.

However, in the configuration shown in FIG. 3, since the water level switch 2 is fixed to the bathtub 1, there is a problem that an arbitrary water level cannot be achieved.

Therefore, as shown in FIG. 4, in which the same parts as in FIG. An automatic bath system has been proposed that detects the water level of the bathtub 1 and determines the water level of the bathtub 1.

With the configuration shown in FIG. 4, for example, it is not possible to detect a case where the stopper of the bathtub 1 is disconnected and hot water does not accumulate.
Furthermore, when adding new hot water while there is still hot water remaining in the bathtub 1, it is not possible to know the amount of hot water remaining.

As a conventional technique for knowing the amount of remaining hot water, there are two water level setting methods described, for example, in Japanese Patent Application Laid-Open No. 15047/1983.

FIG. 5 is a schematic diagram showing the configuration of an apparatus for carrying out the first water level setting method. In FIG. 5, in which the same parts as in FIG. 4 are given the same reference numerals, 9 is a heat exchanger in which a circulation system and an input system are integrated, 10 is a bath water supply pipe, and 11 is a bath water return pipe. tube, 12
is a thermistor installed in the middle of the bath water return pipe 11.

The remaining hot water 8 in the bathtub 1 is circulated through the path of bath return pipe 11 → heat exchanger 9 → bath water outgoing pipe 10 → bathtub 1, and the initial hot water temperature T1 of the remaining hot water 8 and the hot water temperature after heating T2
is detected by the thermistor 12, and the remaining amount Q of the remaining hot water 8 is calculated using the following equation (a).

Q=(I×t)×η/(T2−T1) …(a) Here, (I×t): Total calorific value I: Calorific value per unit time of burner t: Heating time by burner η: Heat Thermal efficiency of the exchanger (T2 - T1): amount of change in water temperature In addition, the second water level setting method described in the above publication includes a flow sensor 13 in the bath temperature circulation system, as shown in Figure 6. At the same time, thermistors 12 and 14 are provided before and after the heat exchanger 9 in the circulation system, and the inlet side temperature T2, outlet side temperature T3, and circulation amount per unit time of the heat exchanger 9 are measured, and the heating timer time t,
Using the initial hot water temperature T1, calculate the remaining hot water amount Q from the following formula (b).

Q=(T3-T2)××t/T2-T...(b) [Problem to be solved by the invention] The conventional water level setting method calculates the amount of hot water remaining in the bathtub as described above. The first water level setting method shown in Figure 5 has large errors due to changes in burner combustion amount due to aging, changes in heat exchanger thermal efficiency, changes in piping and bathtub system thermal efficiency, etc., making it impractical. poor.

In addition, the second water level setting method shown in FIG. 6 requires a flow rate sensor 13 and a temperature sensor 14 in the circulation system in addition to the sensor 12 shown in FIG. There were problems such as decreased reliability due to sensor clogging, accuracy variations in the flow rate sensor, and errors caused by heat loss in the piping system.

This invention was made to solve the above-mentioned problems, and an object thereof is to provide a water level setting method that allows the amount of remaining hot water to be determined with high accuracy.

[Means for solving problems]

The water level setting method according to the present invention measures the heating time required to raise the temperature of the remaining hot water in the bathtub to a predetermined temperature in the first timing step, and then adds the hot water measured in the measuring step to the remaining hot water. The heating time required to raise the temperature of the added hot water to a predetermined temperature is measured in a second timing step, and the first and second heating times measured in the first and second timing steps and the measuring step are The current amount of remaining hot water is calculated in the calculation process from the additional amount of hot water measured in .

[Effect]

The water level setting method in this invention is based on a heating time required to heat the remaining hot water in the bathtub to a predetermined temperature, a known amount of additional hot water added to the remaining hot water, and a heating time required to heat the added hot water to a predetermined temperature. By calculating the current amount of hot water remaining in the bathtub in a calculation process, it is possible to know the amount of remaining hot water with high precision using existing equipment.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing the configuration of an apparatus for carrying out the water level setting method of the present invention, and is basically the same as FIG. 5 described above.

Figure 2 is a flowchart showing the process of calculating the amount of remaining hot water.
(°C), initial remaining hot water amount Q ₀ (l), additional pouring amount ΔQ (l),
The time t ₁ required to increase the initial residual hot water amount Q ₀ by temperature ΔT,
The current amount of remaining hot water after additional pouring Q _PV (Q ₀ + ΔQ), the total calorific value of the burner AKcal/min, the efficiency η including the heat exchanger and piping system, the time required to raise the current amount of remaining hot water Q ₀ + ΔQ by the temperature ΔT Let t be ₂ .

Next, the process of calculating the amount of remaining hot water will be explained with reference to the flowchart shown in FIG. First, it is detected whether or not there is any remaining hot water in the melting tank, for example, using a water flow switch (not shown) installed in the circulation system (step ST-1), and it is determined whether the amount of remaining hot water is sufficient ( Step ST-
2) If the remaining hot water is not enough, for example, set hot water amount Q _SP
Pour 1/2 of the amount into the bathtub (Step ST-3).

Next, after heating the remaining hot water in the bathtub to, for example, 38°C (step ST-4), this remaining hot water is further heated to a predetermined temperature, for example, from 38°C to 39°C (step ST-5). The first heating time required is
When t ₁ , ΔT・Q ₀ =A・η・t ₁ (1) holds true.

Next, heating of the remaining hot water is stopped, the amount of hot water measured by a flow rate sensor as a metering means is added to the remaining hot water (step ST-6), heating is performed again, and the added hot water is heated to a predetermined temperature, e.g. Heat to 1℃ (step
ST-7), the second heating time required for this heating is t ₂
Then, ΔT・(Q ₀ +ΔQ)=A・η・t ₂ (2) holds true.

Therefore, from equation (2) - (1) above, A・η=ΔT・ΔQ/t ₂ −t ₁ ...(3) Also, from equation (2) - (3), Q ₀ +ΔQ=ΔQ・t ₂ /t ₂ −t ₁ …(4) holds, and from this equation (4), the current amount of hot water remaining in the bathtub
Calculate Q _PV (step ST-8).

After this calculation, by pouring while measuring the additional pouring amount Q _add = (Q _SP − Q _PV ) with the flow sensor,
You can fill the bathtub with a preset amount of hot water.
In this case, if the pulse counts of the flow rate sensors that measure the set hot water amount Q _SP and the additional hot water amount ΔQ are respectively N _SP and ΔN, then Q _add = Q _SP −ΔQt ₂ /t ₂ −t ₁ = KN _SP −KΔNt ₂ / It is expressed as t ₂ −t ₁ =K(N _SP −ΔNt ₂ /t ₂ −t ₁ )=K·N _add , and the additional pouring amount Q _add can be determined by counting N _add . In other words, N _add = N _SP −ΔNt ₂ /t ₂ − t ₁ , and this N _add includes the proportional coefficient K of the flow sensor.
Variation factors such as these are not included. Therefore, the amount of poured molten metal can be measured without error.

Although the above embodiments have been described as additional hot water, the same applies to additional water.

〔Effect of the invention〕

As described above, according to the present invention, the first heating time required to raise the temperature of the remaining hot water to a predetermined value, the known amount of additional hot water, and the second heating time required to raise the temperature of the hot water after addition to a predetermined value. The method calculates the current amount of hot water remaining in the bathtub, so it eliminates factors such as variations in the efficiency of heat exchangers and burners, variations in heat loss in the piping system including the bathtub, and variations in accuracy of the flow rate sensor. The amount of hot water remaining in the tank can be calculated with high accuracy. In addition, since the heating time and the amount of additional hot water can be measured using existing systems and sensors, there is an advantage that no new cost increases occur.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing the configuration of a device for implementing the water level setting method according to the embodiment of the present invention, Fig. 2 is a flowchart showing the process of calculating the amount of remaining hot water, and Fig. 3 is a schematic diagram of the configuration of a conventional automatic bath system. 4 is a block diagram showing another schematic configuration, FIG. 5 is an explanatory diagram of the conventional water level setting method, and FIG.
The figure is an explanatory diagram of another water level setting method. ST-5 is the clock step of the first heating time, ST-6
ST-7 is the process of measuring the amount of additional hot water, ST-7 is the process of measuring the second heating time, and ST-8 is the calculation process.

Claims (1)

[Claims] 1. A first timing step of measuring the heating time required to raise the temperature of the remaining hot water in the bathtub to a predetermined temperature, a measuring step of measuring the amount of hot water to be added to the remaining amount, and a step of measuring the amount of hot water in the bathtub to which the amount of hot water has been added. a second timing step of measuring the heating time required to raise the bathtub to a predetermined temperature, and calculating the current amount remaining in the bathtub from the heating time measured in the first and second timing steps and the additional amount of hot water measured in the measuring step. A bath water level setting method comprising a calculation process for calculating the amount of hot water.