JP2000111147A - Method of setting water level of bath hot water supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of setting the water level in a bath hot water supply device capable of highly accurate detection of the quantity of hot water in a bathtub under any condition, especially, even in case that the temperature of the hot water already accumulated in a bathtub is close to the set temperature of a bath and that the temperature of the hot water added from a hot water supplier to the bathtub is low. SOLUTION: This is a bath hot water supplier which is equipped with a hot water supplier 2 for letting fall a specified quantity of warm water set optionally by a user and a bath hot water circulating heater 3 for additionally stoking the hot water let fall, and in this bath hot water supply device which adds a fixed quantity of hot water at a fixed temperature from a hot water supplier 2 to a certain quantity of hot water accumulated in a bathtub 19 when letting fall the specified quantity of hot water to the bathtub, and computes the quantity of hot water at that point of time by the variation of the hot water through the pouring of this hot water, and compares this computed quantity of hot water with the said specified quantity mentioned above, and replenishes hot water in a quantity equivalent to the difference between both from the hot water supplier 2, the output of a circulating hot water detecting thermistor 18 arranged to measure the temperatures of hot water before and after pouring is inputted into a microcomputer after being amplified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention automates a series of operations in which a bath water heater, specifically, a predetermined amount of hot water or water is dropped into a bathtub in a first operation and then heated to a set temperature by a bath water circulation heater. The present invention relates to an apparatus having a process of dropping bath water to at least a certain water level, such as a bath water heater, provided with a thermistor for measuring bath water temperature.

[0002]

2. Description of the Related Art Conventionally, in this type of hot water supply apparatus, as shown in Japanese Patent Publication No. 1-305105, a certain amount of hot and cold water is added from a hot water supply to a certain amount of hot and cold water stored in a bathtub.
The amount of hot water at that time is calculated from the amount of change in hot water temperature before and after the pouring, and the calculated hot water amount is compared with the predetermined amount set in advance, and hot water is supplied in an amount corresponding to the difference between the two. There is a bath water heater to supply from.

[0003]

However, since the bathtub hot water amount is calculated using the measured results of the bathwater temperature before and after pouring, a slight error in the measured hot water temperature may cause the calculation result of the bathtub hot water amount to vary depending on the conditions. There is a problem that a large error occurs. Particularly, when the temperature of the hot water already stored in the bathtub is close to the bath set temperature and the temperature of the hot water added to the bathtub from the water heater is low, a particularly large error occurs. Had the problem that

[0004] In view of the above problems, an object of the present invention is to provide a method for setting a water level of a bath water heater, which is capable of detecting bath water quantity with high accuracy under any conditions.

[0005]

Means for Solving the Problems To achieve the above object, a bath water heater of the present invention comprises a water heater for dropping a predetermined amount of hot water arbitrarily set by a user, and reheating the dropped water. A bath water heater provided with a bath water circulation heater, wherein, when dropping the predetermined amount of water in the bath, add a certain amount of hot water from the water heater to a certain amount of water stored in the bath, The amount of hot water at that time is calculated from the amount of change in hot water temperature before and after the pouring, and the calculated hot water amount is compared with the predetermined amount set in advance, and hot water is supplied in an amount corresponding to the difference between the two. Is characterized in that the output of a circulating hot water temperature detecting thermistor arranged to measure the hot water temperature before and after the pouring is amplified and then input to the microcomputer.

According to the water level setting method of the bath water heater according to the first aspect, the accuracy of input to the microcomputer of the circulating hot water temperature detecting thermistor is increased, so that the bath tub hot water amount detection can be performed with high accuracy. A water level setting method for a bath water heater can be provided.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS This will be described below with reference to the illustrated embodiment. FIG. 1 is a schematic configuration diagram of an embodiment of a bath water heater to which the present invention is applied, and FIG. 2 is a schematic configuration diagram of an input circuit to a microcomputer of a circulating hot water temperature detection thermistor which is a requirement of the present invention. In FIG. 1, reference numeral 1 denotes a bathtub with a water heater, in which an instantaneous water heater 2 and a bath water circulation heater 3 are arranged side by side. The instantaneous water heater 2 comprises a heat exchanger 4 for hot water supply, a burner 5 for heating the same, a water inlet pipe 6 connected to a city water supply, a hot water pipe 7 and the like. I have.

On the other hand, the bath water circulation heater 3 has a circulation heat exchanger 12, a burner 13, a bath water going pipe 14, and a bath water return pipe 1.
5, a self-priming pump 16 disposed in the return pipe 15, a flow switch 17 disposed upstream of the pump 16, a circulating hot water temperature detecting thermistor 18, and the like. Here, as shown in FIG.
The output of the circulating water temperature detection thermistor 18 is wired so as to pass through an amplifier circuit and then be input to a microcomputer. The ends of the going pipe 14 and the return pipe 15 are opened on the side wall of the bathtub 19 in the bathroom. Reference numeral 20 denotes a hot water supply pipe connecting the hot water supply pipe 7 downstream of the hot water temperature detection thermistor 10 and the pump outlet side of the return pipe 15. Vacuum break valve 23 and check valve 24. 26 is a gas solenoid valve provided in a gas path to the burner 13, and 27 is an exhaust fan for discharging waste gas from both heaters 2 and 3 to the outside.

In addition, the bath kettle 1 with the water heater of the above-described configuration is composed of 1
Although provided on the floor, the bathtub 19 may be provided on the second floor as shown by a chain line in addition to being provided on the first floor as shown by the solid line in the figure. In this case, the vacuum break valve 23 is set up at a position above the water surface of the bathtub on the second floor as indicated by a chain line. Reference numeral 28 denotes a remote controller provided near the bathtub 19, which has a power switch 29, a hot water temperature control knob 30, a hot water reheating switch 31, a bath automatic switch 32, a bath temperature setting knob 33, a hot water setting knob 34, and the like. . 35 is a controller for centrally controlling various functions of the bathtub 1 with a water heater, and has a built-in microcomputer.

Next, in such a configuration, the process of setting the drop amount according to the present invention will be described with reference to the flowchart shown in FIG. When the bath automatic switch 32 is turned on, the pump 16 is driven, and the circulating hot water temperature detection thermistor 18 detects the initial hot water temperature (T1). At this time, if the flow rate switch 17 does not operate, that is, if there is not enough hot water circulating in the bathtub 19 yet, the water heater 2
After dropping a certain amount of hot water from the side,
The pump 16 is driven again. When the flow rate switch 17 is turned on, the hot water temperature (T1) is measured, amplified as described above, and stored in the memory of the microcomputer in the controller 35. Next, the hot water at a constant temperature (T3) from the water heater 2 is measured by the flow rate sensor 21 with the solenoid valve 22 opened, and a constant amount (Q3) is measured.
3) Drop it. The hot water temperature (T3) at this time is measured by the hot water temperature detection thermistor 10. Then, the pump 16 is driven again, and the temperature (T2) of the bath water is detected by the circulating water temperature detection thermistor 18, and the temperature is amplified and stored in the memory of the microcomputer. From these measured values, the amount of hot water (Q2) present in the bathtub 19 and the circulation path is calculated by the following equation. Q2 = (T3-T1) × Q3 / (T2-T1)

The amount of hot water (Q2) obtained in this way is
Set the amount of hot water (Q1) in advance with the hot water amount setting knob 34 (this is the amount of hot water to be finally stored in the bathtub, for example, 180 liters)
It is sufficient to add while measuring with the flow rate sensor 21 the shortage of hot water (Q2-Q1).

The present invention has such a structure. To automatically boil a bath, a power switch 29 is turned on by a remote controller 28, and a bath temperature setting knob 33 and a water amount setting knob 34 are previously set to an arbitrary temperature and water amount. Then, the automatic switch 32 may be pressed. As a result, the above-described operation of calculating the necessary water replenishment amount is performed, and then the process proceeds to the next operation.
That is, the electromagnetic valve 22 is opened, water flows, the water heater 2 operates, the burner 5 is ignited, and hot water of an appropriate temperature (for example, 38 ° C.) fixed in advance flows from the bath water supply pipe 20 to the return pipe 15. At this time, the replenishment flow rate measurement by the flow rate sensor 21 is started, and the hot water is separately sent out both in the direction of the pump 16 of the return pipe 15 and in the direction of the heat exchanger 12, and gradually accumulates in the bathtub 19. When the flow rate sensor 21 measures hot water supply for the previously calculated rehydration amount, the electromagnetic valve 22 closes and the operation of the water heater 2 stops, and then the pump 16 starts to rotate and a forced flow occurs in the circulation path, When this is detected by the flow switch 17, the burner 13 is ignited and the circulating hot water is supplied to the thermistor 1.
The boiler 8 boiles and stops until a preset hot water temperature is detected.

During this heating, the bath water is spouted vigorously into the bath tub 19, so that there is no difference between the upper and lower temperatures and the bath water is uniformly heated. When the bath water is cooled and reheating is required, when the reheating switch 31 is turned on, the temperature is increased by heating in the heat exchanger 12 while being forcedly circulated by the pump 16,
The reheating is stopped by detecting the set temperature of the thermistor 18. In order to supply hot water to the kitchen or the like, it is only necessary to open the hot water supply curl at the place where the water is used, and the hot water is supplied after the flow rate sensor 8 starts detecting the water flow, as in the case of the above-mentioned bath hot water supply.

Here, a supplementary explanation of the requirement of the present invention that the output of the circulating hot water temperature detecting thermistor 18 is inputted to the microcomputer after passing through the amplifying circuit will be given. As shown in FIG. 5, in the conventional embodiment, the output of the circulating water temperature detecting thermistor 18 was directly input to the microcomputer and calculated, whereas as shown in FIG. Since the output of the detection thermistor 18 is input to a microcomputer after passing through an amplifier circuit and used for calculation, in the conventional example, for example, the temperature was 0 to 5 V and 0 to 128 ° C. as shown in FIG. By amplifying, a wide voltage width (for example, 0 to 10 V) even at the same temperature width (for example, 0 to 128 ° C.)
As a result, when the voltage width (for example, 0 to 5 V) is adjusted, as shown in FIG.
1.2 ° C.), the accuracy of input of the detected temperature of the circulating water temperature detection thermistor 18 to the microcomputer is increased, and as a result, the calculation accuracy of the bath water amount calculated by using the value is increased. .

For example, referring to FIG. 7, when the output of the circulating hot water temperature detecting thermistor 18 is directly input to the microcomputer, for example, when the output is divided into 256, the input accuracy becomes smaller by 0.5 ° C. (128 ÷ 256 = 0). 5), when input to the microcomputer through the amplifier circuit as shown in FIG.
(÷ 256 = 0.2).

Here, as an example, T1 = 40 ° C., T3 = 2
Considering the case of 0 ° C., Q3 = 15 liters, and T2 = 38 ° C., when the circuit of FIG. 5 is used, this T2 may be input to the microcomputer as 37.5 ° C. On the other hand, when the circuit of FIG. 2 is used, T2 is set to 37.8 ° C. by the microcomputer.
May be entered. Further, as described above, the microcomputer calculates the amount of hot water (Q2) present in the bathtub 19 and the circulation path by the following equation. Q2 = (T3−T1) × Q3 / (T2−T1) By substituting these values into the above equation, as a calculation result which should be originally, Q2 = (20−40) × 15 / (38−40) = 150 In the conventional embodiment, that is, when the circuit of FIG. 5 is used, Q2 = (20−40) × 15 / (37.5-40) = 120 On the other hand, when the present invention is applied, that is, the circuit of FIG. In this case, Q2 = (20−40) × 15 / (37.8−40) = 136, and the detection amount Q2 should be calculated with 150 liters.
An error of as much as -120) liters (20%) occurs, and in the present invention, the error can be suppressed to 14 (= 150-136) liters (9.3%).

[0017]

According to the above-described structure, the method for setting the water level of the bath water heater of the present invention enables highly accurate detection of the amount of bath water under any condition, and thus the water level can be set with high accuracy. That is, the convenience of the user can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a bath water heater to which the present invention is applied.

FIG. 2 is a schematic configuration diagram of an input circuit to a microcomputer of the circulating hot water temperature detection thermistor of the present invention.

FIG. 3 is a flowchart showing a process of setting a drop amount according to the present invention.

FIG. 4 is a conceptual diagram of a method for detecting the amount of hot water in a bathtub.

FIG. 5 is a schematic configuration diagram of a conventional input circuit to a microcomputer of a circulating hot water temperature detection thermistor.

FIG. 6 is a graph showing a relationship between a circulating hot water temperature detection thermistor detection temperature and a microcomputer input voltage when the present invention is applied. .

FIG. 7 is a conventional relational graph of circulating hot water temperature detection thermistor detection temperature versus microcomputer input voltage.

[Explanation of symbols]

 Reference Signs List 1 bath kettle with water heater 2 instantaneous water heater 3 hot water circulation heater 4 hot water supply heat exchanger 10 hot water temperature detection thermistor 12 circulation heat exchanger 16 pump 17 flow rate switch 18 circulation hot water temperature detection thermistor 19 bathtub 28 remote control 35 Controller

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hideya Kotobuki, 93 Edocho, Chuo-ku, Kobe, Hyogo Prefecture Inside Noritz Co., Ltd. (72) Eiichi Tsuji 93, Edocho, Chuo-ku, Kobe, Hyogo Co., Ltd. In Noritz (72) Inventor Koji Kishio 93F, Edo-cho, Chuo-ku, Kobe-shi, Hyogo F-term in Noritz Corporation (Reference) 3L024 CC08 DD06 DD17 DD22 EE12 GG05 GG06 GG18 GG22 HH04 HH12

Claims (1)

[Claims] 1. A bath water heater provided with a water heater for dropping a predetermined amount of hot water arbitrarily set by a user, and a bath water circulation heater for reheating the dropped hot water, the bath water being provided in the bathtub. When dropping a fixed amount of hot water, add a certain amount of hot water at a certain temperature from a water heater to a certain amount of hot water stored in the bathtub, calculate the hot water amount at that time from the hot water temperature change before and after this pouring, In order to measure the hot water temperature before and after the pouring in a bath water heater that compares the calculated hot water amount with the predetermined amount set in advance and supplies hot water from the hot water heater in an amount corresponding to the difference between the two. A water level setting method for a bath water heater, comprising: amplifying an output of a circulating hot water temperature detection thermistor and inputting the amplified output to a microcomputer.