JPH07218313A - Method and apparatus for detecting amount of water in bathtub - Google Patents

Abstract

PURPOSE:To remotely detect the amt. of water in a bathtub by mainly providing a heat exchanger, a temp. sensor, a circulation route and a control means and operating the amt. of water in the bathtub from respective elements of heating, a temp. rise and a time. CONSTITUTION:The hot water 4C of a bathtub is sent to a heat exchanger (additional burning heat exchanger 22) under pressure by a pump 56 through a circulation route (additional burning circulation pipeline 60) to be circulated to the bathtub to stirr the hot water 4c in the bathtub. The temp. of the hot water reaching definite temp. by stirring in the bathtub is detected on the side of the circulation route and a heat exchanger 28 is operated on the basis of this temp. detection. The hot water 4b circulated by the pump 56 is heated to heat the hot water 4c in the bathtub by predetermined temp. and the heating time required to raise the temp. of the hot water 4c by predetermined temp. is measured. By dividing the product of the heating time and the quantity of the heat applied to the hot water 4b by the heat exchanger 22 by raised temp., the amt. of the water in the bathtub is calculated by a control means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting the amount of water in a bath and an apparatus therefor for remotely detecting the amount of water in the bath.

[0002]

2. Description of the Related Art In an automatic bath heater, when controlling the amount of water in a bathtub, it is essential to detect the amount of water in the bathtub.
In order to detect the amount of water, a water level detection device such as a pressure switch or a water level switch that directly detects the water level in the bathtub was required.

[0003]

By the way, in the automatic bathtub, a method of transferring hot water heated on the equipment main body side having a heating means or the like to the bathtub side by using a pump is further adopted. Some have a reheating function that returns the hot water in the bathtub to the body of the equipment and reheats it. In such an automatic bath kettle, the appliance main body provided with the heating means and the bathtub are installed apart from each other. For example, the appliance main body may be installed on the first floor of the house and the bathtub may be installed on the second floor. . In such a case, the control signal line that connects the water level detection device installed in the bathtub and the control device that controls the instrument body, the installation position of the control device, and the like are complicated, which requires labor.

In addition, in order to detect the water level on the bathtub side, there is an automatic bathtub in which the amount of water to be supplied to the bathtub is optimized by measuring the amount of water on the instrument body side. With such a bath kettle, an appropriate amount of water can be supplied to the volume of the bathtub, but the water level in the bathtub is indirectly calculated on the instrument body side, so of course, the amount of water reduced by bathing, etc. Cannot be detected on the instrument body side.

In any bathtub, a water level detecting device must be installed, and wiring for that is required.

Therefore, the present invention provides a method and apparatus for detecting the amount of water in a bathtub, which remotely detects the amount of water in the bathtub by calculating the amount of water in the bathtub from each element of heating, temperature rise, and time. The purpose is to provide.

[0007]

The method for detecting the amount of water in the bathtub according to the present invention is a method for detecting the amount of water in a bathtub (20) in which a predetermined amount of water is stored, as illustrated in FIG. 4c) is pumped to the heat exchanger (heat exchanger 22 for additional heating) by the pump (56) through the circulation path (additional circulation pipeline 60) and circulated in the bath, thereby stirring hot and cold water in the bath, The temperature of hot and cold water in the bathtub, which is kept constant by stirring, is detected on the circulation path side, and based on this temperature detection, the heat exchanger is operated and the hot and cold water circulating in the pump is heated to a predetermined temperature. The amount of water in the bathtub can be calculated by measuring the heating time required to raise the temperature of the hot water by a predetermined temperature and dividing the product of this heating time and the amount of heat added to the hot water by the heat exchanger by the rising temperature. It is characterized by calculating.

Further, the water amount detecting device in the bathtub according to the present invention is a water amount detecting device in the bathtub in which a predetermined amount of water is stored, and hot water of the bathtub is pumped to a heat exchanger by a pump and circulated in the bathtub. A circulation path (additional circulation pipeline 60) for stirring hot and cold water in the bathtub, and a temperature sensor (70) for detecting the hot and cold water temperature in the bathtub that is kept constant by the stirring on the circulation path side, Based on this temperature detection,
The heat exchanger is operated to heat the hot and cold water so that the hot and cold water in the bathtub is heated to a predetermined temperature, the heating time required to raise the hot and cold water to a predetermined temperature is measured, and this heating time and the heat exchanger are added to the hot and cold water. A control means (main device 72) for calculating the amount of water in the bath by dividing the product of the amount of heat and the increased temperature is provided.

In the method and apparatus for detecting the amount of water in the bath according to the present invention, the amount of heat added to the hot water is given by the product of the amount of heat generated by the burner for heating the heat exchanger and the thermal efficiency. For this thermal efficiency, the product of the constant amount of water in the bath and the rising temperature obtained by heating this amount of water in a heat exchanger is divided by the product of the time required to reach the rising temperature and the calorific value of the burner. The value obtained by doing so is used.

Further, in the method and apparatus for detecting the amount of water in the bath according to the present invention, the thermal efficiency is such that the constant amount of water in the bath and the rising temperature obtained by heating the amount of water in the heat exchanger for each additional heating. The value obtained by dividing the product by the product of the time required to reach the rising temperature and the calorific value of the burner is updated, and that value is referred to as the thermal efficiency for the next reheating.

[0011]

In the method and apparatus for detecting the amount of water in the bathtub according to the present invention, the water 4c in the bathtub 20 is pressure-fed by the pump 56 through the circulation path (additional circulation pipeline 60) and passes through the heat exchanger 22. The hot and cold water 4c in the bathtub 20
To heat. Assuming that the time required for the water temperature in the bathtub 20 to rise by a constant temperature ΔT according to the heating is t and the heating capacity of the heat exchanger 22 is No, the bathtub 20
The amount Q of water inside is given by Q = No · t / ΔT (1). As a result, the amount of water Q in the bathtub 20 can be calculated.

Therefore, in the bath kettle in which the water 4c in the bathtub 20 is circulated and heated in the heat exchanger 22 with respect to the actual bathtub 20, the amount Q of water in the bathtub 20 is equal to that of the heat exchanger 22. Calorific value of the combustion burner 24, that is, combustion capacity N (=
No) and the time t required to increase by the specific temperature ΔT
From the above, the water amount Q (= N · t / ΔT) can be detected by the equation (1).

The amount of heat added to the hot water through the heat exchanger 22 is given by the product of the calorific value of the burner and the thermal efficiency. In this case, the thermal efficiency is the product of the constant amount of water in the bath and the rising temperature obtained by heating this amount of water in the heat exchanger, which is the product of the time required to reach the rising temperature and the calorific value of the burner. The value is obtained by dividing, and this value is obtained at the time of additional heating, for example.

Therefore, this thermal efficiency can be calculated based on the detected value obtained for each additional heating, and the value can be updated. That is, by using the thermal efficiency obtained for each additional heating at the time of the next additional heating, the amount of water in the bathtub can always be calculated using the latest data.

[0015]

The present invention will be described in detail below with reference to the embodiments shown in the drawings. FIG. 1 shows an embodiment of a method for detecting the amount of water in a bath and an apparatus therefor according to the present invention, which is an automatic bathtub.

As shown in FIG. 1, the water 4a consisting of tap water supplied from a water supply or the like passes through the hot water supply water flow switch 26, whereby the water flow is electrically detected, and Dw1
Represents the hot water supply water flow detection signal obtained by the hot water supply water flow switch 26. The water 4a is used as a heat exchanger 2 as a heating means.
8 and the hot water supply burner 30.

A combustion gas 32 is supplied to the hot water supply burner 30.
It is supplied through a main valve 34 and a hot water supply valve 36 whose opening / closing is electrically controlled, Cv1 represents an open / close control signal of the main valve 34, and Cv2 represents an open / close control signal of the hot water supply valve 36. The gas 32 supplied to the hot water supply burner 30 is ignited by an igniter 38 which is electrically ignited as an ignition means, and Sf1 represents its ignition signal. The presence / absence of ignition of the gas 32 is detected by a flame detector 40 called a flame rod which electrically detects the presence / absence of a flame, and Df1 represents an ignition detection signal.

Then, the hot water 4b obtained by passing through the heat exchanger 28 passes through the hot water supply temperature detector 42 which is provided as a temperature detecting means and which is composed of a thermistor for electrically detecting the hot water supply temperature. , Its temperature is detected. At1
Represents the hot water supply temperature detection signal. The hot water 4b that has passed through the hot water supply temperature detector 42 is guided to the hot water supply / pouring changeover valve 44 that electrically switches the hot water supply / pouring direction, and is directed to the hot water supply port 46 side by the hot water / pouring changeover signal Sh1. The supply and the pouring to the bath 20 side are switched.

The hot water 4b led to the pouring side b through the hot water / pouring changeover valve 44 is detected by the water flow rate sensor 47 which electrically detects the flow rate, and Dm is the water flow rate detection signal. Represent. The hot water 4b that has passed through the water flow rate sensor 47 is guided to a reheating / pouring switching valve 50 that electrically switches the hot water supply direction via a hopper 48 that shuts off the water supply side, and a reheating / pouring switching signal. It is switched to the reheating side or the pouring side according to Sh2.

In this case, on the pouring side c, in the direction shown by arrow B, the hot water 4b from the pipe 52 directly connected to the bath 20 is passed through the pump 56 that electrically circulates water to the bath 20. Supplied. Dr represents a pump drive signal for driving the pump 56.

On the reheating side d, the reheating / pouring changeover valve 5
The pouring is prohibited by 0, and the water 4c in the bathtub 20 for heating the bathtub 20 is switched between pouring and pouring in the direction indicated by the arrow A through the circulation port 54 in the bathtub 20. It is circulated through the pump 56 by the additional heating circulation line 60 as a circulation path including the additional heating side passage of the valve 50.

The water 4c passing through the reheating circulation line 60 is
It is detected by a water flow sensor 62 that electrically detects the presence or absence of a water flow, and Dw2 represents the detection signal.

The reheating circulation pipe 60 is provided with a reheating heat exchanger 22 and a reheating burner 24 as heating means, and the water 4c in the bath 20 is heated by the reheating. In this case, the combustion gas 32 is supplied to the reheating burner 24 through the reheating gas valve 64 whose opening and closing is electrically controlled, and the opening and closing of the reheating gas valve 64 is controlled by the opening and closing control signal Cv3. The combustion gas 32 supplied to the additional heating burner 24 is
As in the case of the hot water supply burner 30, it is ignited by an igniter 66 that is electrically ignited as an ignition means, and Sf2 represents its ignition signal. The presence or absence of ignition of the combustion gas 32 is detected by a flame detector 68 that electrically detects the presence or absence of a flame, and Df2 represents an ignition detection signal.

Then, the bathtub 20 heated by additional heating
The water 4c therein is detected by a temperature sensor 70 such as a thermistor that electrically detects the water temperature on the side of the reheating circulation conduit 60, and At2 represents the temperature detection signal.

The system for heating the water 4a, the system for supplying the hot water 4b to the bath 20 or the system for reheating the water 4c in the bath 20 are controlled by the hot water supply control device for heating, supplying or reheating as shown in FIG. Controlled.

This hot water supply control device is composed of a main device 72 and a remote controller 74. The main device 72 is installed on the equipment main body side where the heat exchangers 22 and 28 are installed, and the remote controller. 74 is installed in the bathroom etc. which a bather can arbitrarily adjust from the bathtub 20. Hot water supply water flow detection signal D
The digital data of w1, the hot water supply side ignition detection signal Df1, the hot water supply side water flow rate detection signal Dm, the additional heating water flow detection signal Dw2, and the additional heating side ignition detection signal Df2 pass through the input circuit 721 and the central processing unit (CPU). ) 722. Also,
Since the hot water supply temperature detection signal At1 and the additional heating temperature detection signal At2 are analog signals, they are alternately added to the analog / digital conversion circuit 723 by time division by the multiplexer 724 installed in the input section, and analog / digital converted. After that, it is taken into the CPU 722.

The CPU 722 performs arithmetic processing according to the heating, supply or reheating control program written in the write-only storage element (ROM) 725. In addition, the various data and the data for arithmetic processing that have been taken in are written in a storage element (RAM) 726 that can be freely written and read.

A command for heating, supply or reheating control is performed by operating a switch of the remote controller 74, and the command signal is applied to the remote control transmitting / receiving circuit 727 and the CPU 72
Taken in 2.

Then, the hot water supply side ignition signal Sf1, the opening / closing control signal Cv1, the hot water supply side opening / closing control signal Cv2, and the additional heating side opening / closing control signal C which are various control outputs as the calculation result of the CPU 722.
The output circuit 728 applies the v3, the additional-side ignition signal Sf2, the hot water supply / pouring switching signal Sh1, the additional heating / pouring switching signal Sh2, and the pump drive signal Dr to the controlled objects.

In such a bath kettle, the detection of the amount of water in the bathtub 20 will be described in the order of steps by taking an example of additional heating.

(A) The hot water supply / pouring changeover valve 44 is switched to the hot water supply side a, and the additional heating / pouring hot water changeover valve 50 is switched to the additional heating side d, and the additional heating circulation line 60 is set as a closed loop to set the additional heating mode. To do.

(B) After setting this additional heating mode, the pump 56 is driven to bring the temperature of the water 4c in the bath 20 to the uniform temperature T. In that case, the water temperature T of the bathtub 20 is detected by the temperature sensor 70.

(C) After the temperature of the water in the bath 20 is kept at a constant temperature T, the main valve 34 and the reheating gas valve 64 are opened, and
An ignition signal Sf2 is applied to the igniter 66 to cause a current to flow to generate heat, and the additional burner 24 is ignited.

(D) While the water 4c is being circulated by the pump 56, the temperature of the water 4c in the bathtub 20 is uniformly boiled by a temperature ΔT slightly higher than the temperature To by the additional heating, and the temperature To is changed to ΔT. The required time t is measured and written in the RAM 726.

(E) Then, assuming that the additional combustion capacity N due to the combustion of the additional combustion burner 24 is measured and stored in the ROM 725 in advance, the water amount Q in the bathtub 20 is CP.
In U722, Q = N · t / ΔT is calculated from the equation (1). For example, when ΔT = 1 ° C., the water amount Q in the bathtub 20 is Q = N · t.

The calculation of the amount of water Q in the bath 20 is
The rising temperature ΔT may be detected for a certain time t, and the rising temperature ΔT may be stored in the RAM 726 and calculated from the equation (1).

(F) Since the set amount of water Qo is determined in advance from the volume of the bath 20, the set amount of water is set in the remote controller 74 and the set amount of water Qo and the detected amount of water in the bath 20 are set. The difference water amount ΔQ is calculated from Q and ΔQ = Qo−Q (2).

(G) Then, the warm water 4 of this difference water amount ΔQ
In order to supply b into the bathtub 20, the hot water supply / pouring changeover valve 44
Is switched to the pouring side b and the reheating / pouring switching valve 50 is switched to the pouring side c to supply the hot water 4b into the bath 20.

In this case, the hot water supply burner 30 may be ignited to heat the water 4a to obtain hot water 4b, or the hot water supply burner 30 may be supplied without heating and without heating.

(H) After pouring or pouring an appropriate amount of water, the hot water / pouring changeover valve 44 is switched to the hot water supply side a, and the additional heating / pouring changeover valve 50 is changed to the additional heating side d so that hot water is supplied into the bathtub 20. 4b is boiled to the proper temperature T, and pouring and reheating to the proper amount and temperature of the proper temperature is completed.

When the heat retention and the hot water control are performed, the pouring and reheating of the water in the bathtub 20 are automatically repeated at a fixed time interval so that the water amount Q and the temperature in the bathtub 20 are increased. Optimal control that keeps T constant can be performed.

The boiling time due to additional heating is influenced by the thermal efficiency, but factors that lower the thermal efficiency include the material of the bath, the additional heating pipe, the outside temperature, and the error in the gas pressure set value specific to the appliance. There is. Therefore, the thermal efficiency η is calculated by the following equation: η = Qo × (T2−T1) / S × to (3) by the CPU 722 at each additional heating time, and the RAM 72 is calculated.
It is stored in 6, and the value is updated every time it is fired. Here, Qo is the set amount of water (= the amount of pouring water), T1 is the uniform temperature of the water supplied to the bath 20 during the pouring operation, T2 is the uniform boiling temperature (= set boiling temperature), and to is the boiling time. , S is an additional input capability. That is, Qo x (T
2-T1) is the amount of heat added to hot water, and S × to is the amount of heat generated on the burner side.

In this case, the additional heat input capacity S, which is the amount of heat generated on the side of the additional heat burner, is stored in advance in the ROM 725, and the additional combustion capacity N, which is the amount of heat added to the circulating hot and cold water, is the additional heat input. Product of capacity S and thermal efficiency η (N =
S · η).

[0044]

As described above, according to the present invention, the following effects can be obtained. a. The amount of water in the bathtub can be detected remotely without using electrical signal lines.For example, by detecting the amount of water in the bathtub of an automatic bathtub where the body of the equipment and the bathtub are installed separately. It can be used for controlling water volume. b. Since the amount of water is calculated by measuring the time required to raise the temperature by a certain temperature based on the temperature of hot water, the calculation error due to the heat dissipation loss can be suppressed compared to the case where the time is used as a reference, and the amount of water can be accurately measured. Can be calculated. c. The amount of heat added to hot and cold water is obtained by the product of the calorific value of the burner and the thermal efficiency, and the thermal efficiency is the product of the constant amount of water in the bathtub and the temperature rise obtained by heating this amount of water in a heat exchanger, Since the value obtained by dividing by the product of the time required to reach the rising temperature and the calorific value of the burner is referred to, the heat loss due to the heat exchanger, circulation path, bathtub, etc. can be removed and the circulation Even if the route becomes long, it is possible to always refer to an accurate value and detect an accurate water amount. d. In addition, the thermal efficiency is calculated and updated for each reheating, and the value is referenced at the time of the next reheating, so the water volume can always be calculated with the latest data, and errors due to uncertain factors such as the outside temperature can be eliminated. Accurate water volume detection can be realized.

[Brief description of drawings]

FIG. 1 is a diagram showing an automatic bathtub which is an embodiment of a method and apparatus for detecting the amount of water in a bath according to the present invention.

FIG. 2 is a block diagram showing a hot water supply control device for the automatic bath heater shown in FIG.

[Explanation of symbols]

 4c Water (hot water) 20 Bathtub 22 Heat exchanger for reheating 56 Pump 60 Reheating circulation line 72 Main device of hot water supply control device

Claims (6)

[Claims] 1. A method for detecting the amount of water in a bathtub in which a predetermined amount of water is stored, wherein hot and cold water in the bathtub is pumped through a circulation path to a heat exchanger by a pump to circulate the water in the bathtub. The hot and cold water is stirred, and the hot and cold water temperature in the bath which is kept constant by the stirring is detected on the circulation path side, and based on this temperature detection, the heat exchanger is operated and the hot and cold water circulated by the pump is The hot water in the bathtub is heated to a predetermined temperature by heating, and the heating time required to raise the hot water by the predetermined temperature is measured, and the product of this heating time and the amount of heat added to the hot water by the heat exchanger. The amount of water in the bathtub is calculated by dividing the temperature by the rising temperature. 2. The amount of heat added to the hot and cold water is given by the product of the amount of heat generated by a burner that heats the heat exchanger and the thermal efficiency, and the thermal efficiency is a constant amount of water in the bath and the amount of this heat exchange. It is a value obtained by dividing the product of the rising temperature obtained by heating with a vessel by the product of the time required to reach the rising temperature and the calorific value of the burner. Item 1. A method for detecting the amount of water in a bathtub according to item 1. 3. The thermal efficiency is required to reach the rising temperature by a product of a constant amount of water in the bath and a rising temperature obtained by heating the amount of water in the heat exchanger for each additional heating. The amount of water in the bathtub according to claim 2, wherein the value obtained by dividing the product by the product of the time taken and the calorific value of the burner is updated, and the value is referred to as the thermal efficiency at the time of the next reheating. Detection method. 4. A water amount detection device in a bathtub for storing a predetermined amount of water, wherein hot water in the bathtub is agitated by pumping the hot water in the bathtub to a heat exchanger to circulate the hot water in the bathtub. And a temperature sensor that detects the temperature of hot and cold water in the bathtub, which is kept constant by the stirring, on the circulation path side, and based on this temperature detection, operates the heat exchanger to heat the hot and cold water. The hot water in the bathtub is heated by a predetermined temperature to measure the heating time required to raise the hot water by a predetermined temperature, and the product of this heating time and the amount of heat added to the hot water by the heat exchanger is calculated as described above. A controller for calculating the amount of water in the bathtub by dividing by the rising temperature, and a device for detecting the amount of water in the bathtub. 5. The amount of heat added to the hot and cold water is given by the product of the amount of heat generated by a burner that heats the heat exchanger and the thermal efficiency, and the thermal efficiency is the constant amount of water in the bath and the amount of this heat exchange. It is a value obtained by dividing the product of the rising temperature obtained by heating with a vessel by the product of the time required to reach the rising temperature and the calorific value of the burner. Item 4. A water amount detecting device in a bathtub according to item 4. 6. The thermal efficiency is required to reach the rising temperature by a product of a constant amount of water in the bath and a rising temperature obtained by heating the amount of water in the heat exchanger for each additional heating. The amount of water in the bathtub according to claim 5, wherein the value obtained by dividing the product by the product of the time taken and the calorific value of the burner is updated, and that value is referred to as the thermal efficiency at the time of the next reheating. Detection device.