JPH05346263A - Automatic hot water filling method for bath tub - Google Patents

Abstract

PURPOSE:To perform the filling of hot water to a set water level accurately and quickly by a method wherein a hot water correcting quantity is obtained by the error between the set water level at a test mode and the water level when the filling of hot water is completed, and an automatic filling of hot water is performed by adding this value. CONSTITUTION:Under a test mode, a specified hot water quantity (y) is filled in a bath tub 19 from a reference water level Pb1. A unit required quantity of hot water (y/(Pb2-Pb1)) which generates water level change per a unit height is obtained by the change of the water level. A required quantity of hot water to a set water level Ps is obtained based on the unit required quantity of hot water (y/(Pb2-Pb1)), and that quantity of hot water is filled. When an error is generated between a water level Pw at the completion of hot water filling and the set water level Ps a correcting quantity of hot water Qa (=Q1+Q3=Q2+Q3) is obtained based on the water level difference. At the time of an automatic hot water filling after the test mode, the correcting quantity of hot water Qa is added to determine a required quantity of filling hot water Qr to the set water level Ps. By this method, the filling of hot water to the set water level Ps can be done at a stroke, and the hot water filling time is shortened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a water filling method for pouring hot water up to a set water level in a bath with an automatic hot water supply system.

[0002]

2. Description of the Related Art In recent years, it has become common sense to use a microcomputer (hereinafter simply referred to as a microcomputer) for various controls in an automatic hot water supply system. , Large capacity, and above all, cost reduction act in an accelerating direction,
Various value-added devices have been made from various viewpoints in order to provide the user with more comfort and satisfaction. Among these, one of the most basic functions is the function of automatically pouring hot water to the set water level in the bathtub. Although the present invention also relates to the improvement thereof, first, a recent automatic hot water supply system itself will be described with reference to FIG.

The illustrated automatic hot water supply system or water heater has two heat exchangers 4 and 12, one of which is
A hot water supply heat exchanger 4 for tapping hot water from a hot water tap 1 such as a normal faucet or a shower as needed, or for automatically filling hot water in the bathtub 19, and the other one is a hot water supply in the bathtub 19. This is the heat exchanger 12 for additional heating when the stretched hot water does not reach the set temperature, or when it has cooled down over time. Water from the water pipe is passed through the hot water supply heat exchanger 4 as indicated by the arrow "water", and this water is heated by heating the hot water supply heat exchanger 4 by the burner 5. Be warmed. Of course, the burner 5 is supplied with fuel for combustion, but in the illustrated water heater, as indicated by the arrow "gas",
The most common gas is used as fuel. However, even when kerosene or other fuel is used, the system configuration is almost the same. Therefore, if gas is read as such other fuel, the following description in this document can be applied as it is.

The gas from the gas pipe passes through the original solenoid valve 13, then passes through a dedicated solenoid valve 10 on the hot water supply side, and is further sent to the burner 5 through a solenoid valve (so-called gas proportional valve) 9 for adjusting the gas flow rate. Be done. However, in some cases, the solenoid valve 10 dedicated to the hot water supply side may be omitted and the gas proportional valve 9 may be used instead. The burner 5 is also blown by a fan 6 from time to time with an appropriate amount of air.

On the other hand, the flow rate of water passing through the heat exchanger 4 is detected by a flow rate sensor 8, and the temperature of the water before entering the heat exchanger 4 is detected by the feed water temperature sensor 7 from the heat exchanger 4. The temperature is detected by the hot water temperature sensor 3. Since there is the flow rate sensor 8, the hot water supply amount from a certain time point to a certain time point and the actual pouring amount (total amount or unit pouring amount) into the bathtub 19 relating to the present invention described later are calculated as necessary. With this, the microcomputer 23 can be informed each time.

Except for the presence of a water level sensor 15 which will be described later, the heat exchanger 12 for reheating has no direct relation to the present invention.
To briefly describe the system including, the hot water in the bathtub 19 is guided from the hot water inlet 31 to the circulation flow path, and the circulation flow path passes through the heat exchanger 12 for reheating, and then, again in the bathtub 19. It is connected to the outlet 32 that opens toward the. The heat exchanger 12 for reheating is also selectively heated by the burner 16 similarly to the one for hot water supply described above, but for this burner 16 as well, a dedicated electromagnetic valve is added from the original solenoid valve 13 to the reheating side. Gas as a fuel is selectively supplied through the valve 14, and an air of an optimum flow rate is sent from time to time by a special fan 17 as well. Heat exchanger for reheating 1
When heating 2, the circulation pump 11 works and the bath 19
The hot water inside is passed through the heat exchanger 12 while being circulated. The temperature of the hot water in the bathtub to be reheated is detected by the in-tub hot water temperature sensor 18 provided in the circulation flow path from the hot water inlet 31 to the hot water outlet 32, and the detected temperature is set at that time. The reheating operation is performed until the temperature is reached.

As described above, in the recent automatic hot water supply system of this kind, the control device 21 including the microcomputer 23 causes the detection signals from the above-mentioned various sensors and the main body part of the control device 21 to operate. Performs a corresponding control according to a signal based on the operation of various operation switches attached to a remote controller (hereinafter, simply referred to as a remote controller) provided separately. In FIG. 3, for example, only one remote controller 40 provided in the bathroom is shown, but in many cases, a remote controller can be installed in each of a plurality of places such as a kitchen and a living room.

However, when the system is powered on and the control device 21 is in an operable state, every time the user opens the hot water tap 1 such as a faucet or a shower, the hot water is automatically supplied for hot water supply. Combustion begins. That is, the hot water tap 1
When the water flow through the heat exchanger 4 is opened, the flow rate sensor 8 which has been issuing a water flow stop signal (flow rate zero signal) up to that point is a signal indicating that water has begun to flow (hence the flow rate). The signal can also serve as a water flow on / off detection signal) to the microcomputer 23. Receiving this, the microcomputer 23 sends a signal that gives the gas proportional valve 9 a predetermined valve opening degree (before that, of course, each solenoid valve 10,
13 and 14 are opened), and a corresponding flow rate of gas is supplied to the burner 5, and an air amount control signal (rotation speed control signal) is sent to the fan 6 so that an appropriate amount of air for combustion is supplied. While operating the ignition mechanism (not shown), the ignition mechanism is operated.

When the combustion in the burner 5 is started in this manner, the heat exchanger 4 is heated, the water passing through the heat exchanger 4 is warmed, and the hot water is supplied from the hot water tap 1 such as a faucet. However, this actual hot water supply temperature is also determined by the hot water supply temperature sensor 3
Is detected by the microcomputer 2, and if there is an error with the set temperature set by the user, the microcomputer 2
3 adjusts the valve opening degree of the proportional valve 9 and the rotation speed of the fan 6 in a direction to eliminate such an error, and controls the combustion energy in the burner 5.

When the user closes the faucet or the like that was supplying hot water and stops the hot water, the flow rate sensor 8 sends a water flow stop signal (zero flow rate signal) to the microcomputer 23, and the microcomputer 2 receives this signal.
In No. 3, a fully closed signal is sent to the gas proportional valve 9 via the operation control unit 22 to function to quickly extinguish the burner 5.
However, in some cases, in addition to the flow rate sensor 8 that outputs the actual flow rate in real time, a water flow switch that simply detects whether or not a water flow has occurred may be provided, and
Even if the flow rate is not completely zero, when the flow rate falls below a predetermined flow rate, combustion may be stopped to prevent abnormal heating of the hot water temperature. For safety,
High limit switch (not shown) for heat exchanger 4
In the case where is attached, when this detects an overheated state up to an abnormal temperature and sends an overheat signal to the microcomputer 23, the microcomputer 23 causes the operation control unit 22 to immediately enter the forced extinguishing operation of the burner 5. Similarly, although the combustion amount is limited, the microcomputer 23 also controls the operation control unit 22 when a suitable combustion detection element such as a frame rod detects a mid-fire in the burner 5 (not shown). Then, the gas proportional valve 9 is made to send a forced closing signal, and depending on the system, the former solenoid valve 13 is also made to send a forced closing signal.
Prevent the risk of raw fuel leaking out of the plane.

When the user operates the water filling command switch (not shown) provided on the remote controller 40 and selects automatic water filling in the bathtub 19, the microcomputer 23 built in the control device 21 is operated. A hot water filling request signal is sent to the microcomputer 23. In response to this, the microcomputer 23 opens the switching solenoid valve 2 via the operation control unit 22 so that the hot water from the heat exchanger 4 can be directly introduced into the bathtub 19 via the pipe 24. To

With regard to this automatic filling, one of the necessary data groups is to provide the microcomputer 23 with preset water level data in advance. What is the set water level data? Remote control 4
0 or data for designating which height of the bathtub 19 the hot water should be poured into by the user or installer operating the water level setting means (not shown) provided in the control device 21. This data is represented by the total amount of hot water required from the start of the automatic filling operation to the switching solenoid valve 2 to the bathtub 19 side and the start of pouring hot water into the empty bathtub 19 to the set water level Ps. This is because if the set water level Ps is simply expressed by the geometrical height in the bathtub, it is not possible to deal with the change in bathtub volume. If you use a classic float type liquid level detector that floats in the bathtub, you can simply know the water level by the geometrical liquid level of the hot water in the bathtub, which is preferred in recent markets. Absent. On the other hand, bathtub 19
The actual amount of hot water Qx that is stretched inside is provided in the circulation path that goes around the heat exchanger 12 for additional heating, and the water level sensor 15 that generally takes the form of a pressure sensor determines the water level Px at that time. It is calculated based on the value detected by water pressure conversion. As a result, after a certain amount of time has passed since the start of filling, when the calculated value reaches the pressure value corresponding to the set water level Ps, the operation control unit 22 operates the switching solenoid valve 2 there under the command of the microcomputer 23. Switch to the side.

Of course, the user can set the temperature of the hot water supplied into the bathtub 19 during the automatic filling of the water, and the microcomputer 2 can be used as in the hot water supply to the hot water tap 1 described above.
Reference numeral 3 is an operation control unit 22 for optimally controlling the opening degree of the proportional valve 9 and the rotation speed of the fan 6 based on each information obtained from the flow rate sensor 8, the hot water temperature sensor 7, and the hot water temperature sensor 3. The temperature detected by the hot water supply temperature sensor 3 is always maintained at the set temperature set by the user. After the completion of pouring, if the bath temperature is lower than the set temperature,
In this case as well, the reheating function described above may automatically reheat to the set temperature.

[0014]

As described above, in the conventional automatic hot water supply system, the automatic hot water filling function up to the set water level in the bath is incorporated. And, indeed, as the bathtub 19 has a cubic shape, as shown schematically in the cross section in FIG.
I was able to follow s relatively well. Rather, it can be said that the bathtub 19 was planned to have a cubic shape. However, as is well known, in reality, there are few bathtubs that can be considered as a cube even when considering the allowable range,
If anything, there are many bathtubs that have a shape that gradually expands from the bottom toward the opening. For such a bathtub, the conventional method of capturing various data regarding automatic filling cannot be dealt with.

To explain this in more detail,
The conventional data determination method required for automatic hot water filling has the following steps. First, when the automatic hot water supply system is used for the first time, that is, when the automatic hot water supply system is installed and the first filling of water after the power is first turned on, the predetermined unit hot water amount x (the unit is, for example, liter, It will be abbreviated below). Then, the hot water in the bathtub exceeds the position of the circulation port shown in FIG. 3, particularly the hot water inlet 31, and the water level sensor 15 is immersed in the hot water, so that a significant output is generated in the water level sensor 14.

Therefore, the water level at this point obtained by water pressure conversion is used as the reference water level, and the unit hot water amount x is further poured, and then the water level at that time is detected again by the output of the water level sensor 15. This makes it possible to calculate the height change per unit hot water amount x from the water level difference from the reference water level. Therefore, if the height change per unit hot water amount x is obtained by such a test mode, the subsequent automatic At the time of filling with water, the total required amount of hot water required up to the set water level set each time is calculated by a linear relational expression (primary relation) between the water level difference up to the set water level and the unit hot water amount X that has already been fixed. formula)
, And pour the amount of hot water.

As described above, as long as the shape of the bathtub can be regarded as a cube, the conventional method can satisfactorily follow the difference in the capacity of the bathtub at the time of installation. However, as is apparent, when the shape of the bathtub is not a cubic shape, that is, the shape that cannot be defined by a linear relational expression (a simple integer multiple relationship of the unit amount of hot water) in which the pouring amount and the change of the water level have the unit amount of hot water as a coefficient In the bathtub, the water level error when the pouring is completed is considerably large with respect to the set water level. In addition, since the output of the water level sensor is observed every time the unit amount of hot water is poured, even when the data is determined in the first test mode or when the automatic hot water filling is performed at any time after the second time,
There is also a drawback that it takes time to complete pouring. In view of this point, the present invention can cope well with the difference in volume even in a bathtub having a shape other than a cubic shape in the bath, and even when the set water level is changed in each bath, the water level is as close as possible to the set water level. Up to this, it is designed so that automatic filling can be performed accurately and promptly.

[0018]

In the present invention, in order to solve the above-mentioned problems, when performing automatic hot water filling using the automatic hot water supply system as shown in FIG. (It may be the first time of pouring into the bathtub after the pouring), the pond water level obtained from the water level sensor at the time of pouring a certain amount of pouring water from the start of pouring is the reference water level (Pb1 ), And then pouring a predetermined amount of hot water (y), and when the pouring of the predetermined amount of hot water (y) is completed, the water level in the bathtub (Pb2) obtained through the water level sensor is detected. Then, the unit required hot water amount (Qh) required to obtain the water level change per unit height is obtained from this water level (Pb2), the reference water level (Pb1), and the predetermined hot water amount (y), and based on this, the set water level The total required amount of hot water (Qw-Qb2) required for pouring up to (Ps) is first determined by a linear relational expression, and the amount of hot water corresponding to that is poured. As a result, when there is a water level difference that exceeds the allowable range between the pouring completion water level (Pw) and the set water level (Ps) at the completion of the pouring, based on this difference, the corrected hot water amount related to the change in water level ( Qa) is sought and stored. In addition, at any time of automatic filling after the test mode, the necessary pouring amount (Qr) to be poured is calculated and stored with the already known unit required pouring amount (Qh). Amount of hot water (Q
a), and based on the set water level (Ps) required at that time and the remaining water level (Px) in the bathtub before the start of pouring at that time, determine the amount of water equivalent to the required pouring amount (Qr). Perform pouring.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG. 1. As a premise, an apparatus system as hardware to which the present invention can be applied has already been described with reference to FIG. And Therefore, in this section, re-explanation of the entire system will be omitted, and what is necessary for realizing the present invention will be appropriately extracted and incorporated from the already described contents. The same applies to the reference numerals in FIG. In other words, in other words, as long as the automatic hot water supply system of recent years has a normal function, the present invention can be realized by software processing for the microcomputer 23 incorporated therein.

First, consider the beginning when the automatic hot water supply system shown in FIG. 3 was just installed in a home or the like. As already described, when the power plug (not shown) is inserted into the commercial AC power supply (not shown), the system of FIG. 3 enters the operating state. Therefore, thereafter, it is assumed that the user first issues an instruction to automatically fill the bathtub 19 through the operation of the remote controller 40. As for the automatic filling, as described above, an operation for protecting the set temperature also occurs, but since it is not directly related to the present invention, description thereof will be omitted.

This first automatic filling can be considered as a test mode in the embodiment of the present invention. With the start of the test mode, first, the reference position in the height direction in the bathtub 19 or the reference water level Pb1. To ask for
The molten metal is repeatedly poured into the bathtub 19 for each unit amount x (the unit is arbitrary, for example, liter: hereinafter, unit is omitted). However, when the water level sensor 15 (FIG. 3) is provided at, for example, the circulation port provided for reheating the hot water in the bathtub 19, in particular, at a position Po that is substantially the same as the hot water inlet 31 thereof. If the water level does not rise to that level, the water level sensor 15 naturally does not produce an output. On the contrary, the unit hot water amount x
When an output appears in the water level sensor 15 as a result of continuing the continuous pouring of No., at an appropriate time, for example, at the time when the pouring of the last unit amount of molten water x at which the output appears in the water level sensor 15 is finished, The water level Pb1 that can be detected by the output of the water level sensor 15 at that time is used as a reference water level Pb1, and this reference water level data is stored in a storage unit (not shown) attached to the microcomputer 23 (FIG. 3). Therefore, the reference water level Pb1 is actually slightly higher than the height position Po at which the water level sensor 15 is provided, but this itself does not have a particularly significant meaning for the characteristic control of the present invention. .. From the above, since the pouring amount Qb1 required from the start of pouring to the reference water level Pb1 can also be calculated, this value can be stored in the storage unit as well.

Next, a predetermined amount of hot water y determined in advance
The pouring of the amount (may be the same as or different from the unit hot water amount x) is performed, and the water level Pb2 at the time when the pouring is finished is detected. The total pouring amount Qb2 up to this time is naturally Qb1 + y, but this water level Pb2 and the reference water level Pb1,
And the predetermined amount of hot water poured, Qh = y / (Pb2-Pb1) ... (1) Based on the following formula, the required unit hot water amount Qh required to obtain the water level change per unit height Ask for.

First, a linear relational expression is established. That is, assuming that the bathtub shape is a cube, the total required hot water amount Qw required from the water level zero to the set water level Ps.
Is calculated as Qw = Ps.Qh ... (2). However, in the above test mode, since the water has already been poured up to the water level Pb2 at this point, the set water level Ps
The required amount of hot water is calculated as follows: Qw-Qb2 = (Ps-Pb2) * Qh (3). After that, this amount of hot water (Qw-Qb2)
Pour the water. This corresponds to the case of following the water level vs. hot water amount (PQ) characteristic 1 of the virtual line in FIG.

At the completion of this pouring, the water level sensor 15
If the pouring completion water level Pw detected through the water is equal to the set water level Ps or at least within an allowable range of the allowable range, the shape of the bathtub 19 is as schematically shown in FIG. However, it can be recognized as a substantially cubic shape. Therefore, after the test mode,
When the water level in the bathtub is zero (that is, when there is no hot water) in the state before the start of pouring, the set water level Ps at that time and the unit required hot water amount stored in the storage unit attached to the microcomputer 23. The value Qw obtained by substituting the value of Qh into the above equation (2) is used as the total required pouring amount Qr, and it is sufficient to pour this amount Qr = Qw of pouring water, and it remains in the bathtub before pouring starts. When there is the amount of hot water Px, the amount of hot water obtained by substituting the remaining water level Px detected by the water level sensor 15 for Pb2 in the above equation (3) may be poured.

On the other hand, in the test mode, the amount of hot water (Qw
-If the pouring completion water level Pw detected at the time when pouring is completed is unacceptably different from the set water level Ps, it is determined that the bathtub shape is not a cubic shape. it can. The reason why such an error occurs and the size thereof can be explained by referring to the bathtub 19 having a sectional shape shown in FIG. In other words, as shown in the figure, if the bathtub has a generally cross-sectional shape that expands in a tapered shape from the bottom to the top, pour the amount of hot water obtained by the above equation (3). The actual water level Pw at the end is generally much lower than the set water level Ps.

Here, when it is considered graphically, in the case of a cube, what was supposed to be poured to the set water level Ps was actually lowered to the water level Pw. As shown by the shaded portion Q ₁ in FIG.
Assuming a cubic shape, the volume Q ₁ of the hot water from the water level Pw to the set water level Ps in the bathtub has a volume that swells more than the cubic shape until reaching the pouring completion water level Pw in the bathtub 19 having the sectional shape of FIG. It is used as the amount of hot water to fill Q ₂ . That is, Q ₁ = Q ₂ ... (4).

[0027] Therefore, taking out the tub portion corresponding to the hot water amount Q _2, the illustrated schematically, Do you Manzanillo 2, bottom dimensions a · w, the height h {Pw - (Pb2 + Pb1 ) / 2} It becomes a triangular column-shaped volume region. That is, Q ₂ = a · w · h / 2 = a · w {Pw- (Pb2 + Pb1) / 2} / 2 (5).

Here, since the values of the water levels Pw, Pb1, Pb2 are known and Q ₂ = Q ₁ , even if the above-mentioned bottom face dimension a · w is not known, the value of Q ₁ is calculated _first. The amount of hot water Q ₂ can be obtained by the following equation (3), which is Q ₂ = Q ₁ = (Ps −Pw) · Qh (6).

Therefore, next, the amount of corrected hot water required to bring the hot water that has entered only to the water level Pw to the set water level Ps as in the case of the PQ characteristic 2 of the solid line in FIG. 1 (in this case, Is the corrected hot water amount to be added) Qa, that is, the insufficient hot water amount Qa (= Q ₁ + Q ₃ = Q which is schematically shown in FIG.
₂ + Q ₃ ) is considered to be the height h in FIG. 2 as follows: h ′ = {Ps− (Pb2 + Pb1) / 2} (7) = (H '/ h) ² · Q ₂・ ・ ・ ・ ・ ・ (8)

Therefore, if the above-described calculation is performed in the test mode and the necessary data group obtained is stored in the storage unit attached to the microcomputer 23, the automatic water filling will be performed at any time thereafter. Even if the set water level Ps is changed in (that is, the value h'in the above formula (8) is changed), pouring is completed from the residual water level Px before the start of pouring to the set water level Ps at that time. Required pouring amount Q required for
r can be determined by the following equation (9) using all known stored values or values detectable by the water level sensor 15. Qr = (Ps -Px) · Qh + {(Ps-Pb) 2 - (Px-Pb) 2} · Q 2 / h 2 = (Ps -Px) · Qh + Qa - (Px-Pb) 2 · Q 2 / H ² ; However, Pb = (Pb2 + Pb1) / 2 (9)

Although the preferred embodiment of the present invention has been described above, the test mode described above is not limited to the first automatic water filling after the system is powered on.
It is a matter of design for a person skilled in the art to attach appropriate switches to the system main body etc. so that it can be performed at any time as needed, or to set up a program to perform it regularly. is there.

[0032]

According to the present invention, the corrected amount of hot water Qa is determined by the error between the set water level and the water level when pouring is completed in the test mode.
Is calculated and calculated, and automatic filling is performed with this value taken into account.Therefore, it is possible to accept the difference in the volume of the bathtub that is the target of the automatic hot water supply system quite well, as well as for bathtubs of shapes other than cubes. However, it is more accurate than before, and it is possible to pour up to the set water level at that time all at once, shortening the filling time.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an embodiment for controlling the automatic water filling level in a bath according to the present invention.

FIG. 2 is an explanatory diagram for obtaining a corrected hot water amount.

FIG. 3 is a schematic configuration diagram of a configuration example of an automatic hot water supply system that can be used for carrying out the method of the present invention.

[Explanation of symbols]

 1 Hot Water Tap 2 Switching Solenoid Valve 4 Heat Exchanger for Hot Water Supply 8 Flow Rate Sensor 10 Solenoid Valve for Hot Water Supply Side 12 Heat Exchanger for Reheating 15 Water Level Sensor or Pressure Sensor 18 Bath Water Temperature Sensor 19 Bath 21 Control Device 22 Operation Control Section 23 microcomputer 30 bathroom 40 remote controller provided in the bathroom

Claims (1)

[Claims] 1. An automatic hot water supply system having an automatic hot water filling function for stopping pouring water into a bathtub at a set water level,
An automatic filling method for more accurately matching the water level of the pouring water to the set water level; when pouring in the test mode, a certain amount of pouring water was poured from the start of the pouring. At the time point, the water level in the bathtub obtained through the water level sensor is set as a reference water level (Pb1), and after the reference water level is obtained, pouring of a predetermined amount of hot water (y) is further performed; pouring of the predetermined amount of hot water (y) is completed At this time, the water level in the bathtub (Pb2) obtained through the water level sensor is detected; the water level change per unit height is calculated from the water level (Pb2), the reference water level (Pb1), and the predetermined hot water amount (y). After obtaining the unit required hot water amount (Qh) required to obtain; further, the total required hot water amount (Qw-Qb2) required for pouring up to the set water level (Ps) is linearly related based on the unit required hot water amount (Qh). The pouring amount of hot water corresponding to the amount (Qw-Qb2) obtained by When there is a water level difference between the pouring completion water level (Pw) and the set water level (Ps) at the time of completion, which exceeds the allowable range, the corrected hot water amount (Qa) is calculated based on the difference. At the time of automatic filling in any number of times after the above test mode, the required pouring amount (Qr) to be poured, the unit required amount of hot water (Qh), the corrected amount of hot water (Qa), and the set water level (Ps) at that time. ), And the remaining water level (Px) in the bathtub before the start of pouring that time;
A method of automatically filling the inside of the bathtub.