JP2501470B2 - Bathtub water level control method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a water level control method for a bathtub, which is performed by detecting water pressure in a pipe installed between a water heater and a bathtub.

[Conventional technology]

Conventionally, in fully automatic water heaters and bath heaters, a pressure sensor is installed in the pipe connected between the water heater and the wall surface or bottom surface of the bathtub, and the water level in the bathtub is detected by the water pressure in the pipe, and the detected water level is detected. Depending on the situation, the method of determining the presence or absence of water supply and controlling to the required water level is adopted.

When there is no water in the bathtub, water is fed into the bathtub from the pipe on the opposite side of the pipe where the pressure sensor is installed to raise the detected pressure. Water can be supplied accurately.

Therefore, in such a water level control method, there is no need to install means for detecting the water level in the bathtub, and there is an advantage that the inside of the bathtub can be widely used.

[Problems to be Solved by the Invention]

However, in such a water level control method, when air enters the pipe, the invading air reduces the water pressure in the pipe, and the pressure sensor detects a water level drop or an abnormal pressure.

Especially where the bathtub and the water heater are installed at different places depending on the house, etc.When the bathtub is installed at a low place, air easily enters the pipes and the water level The detection accuracy may be reduced.

Therefore, when performing water filling control or the like by such a water level control method, in advance, an air detection sequence of whether or not air has entered the piping prior to the water level control, and whether hot or cold water remains in the bathtub It is necessary to determine whether or not, and to set up a preliminary sequence for supplementary water supply through the pipe in order to remove the air in the pipe when air enters. The supplementary water supply is performed according to the capacity of the pipe, and when the pipe is long, it is necessary to set the water supply time to be long and to supply a considerable amount of water.

However, once the water is supplied, once the pipe is filled, regardless of its length, as long as the water level in the bathtub does not drop below the level of the pipe, there is no need for supplementary water supply for water level detection. Since there is no intrusion, the air detection sequence and the preliminary sequence are not required, but always operating these sequences during hot water supply increases the dead time and delays hot water supply and temperature rise. There is an inconvenience.

Therefore, an object of the present invention is to provide a water level control method for a bathtub, which constantly monitors the pressure of a pipe and determines whether or not the air level has dropped below a water level at which intrusion of air is realized, thereby realizing an efficient water level control. .

[Means for solving the problem]

The water level control method for a bathtub according to the present invention is shown in FIGS.
As illustrated in the figure, while supplying hot water to the bathtub through the hot water supply circuit, the water level detection means is connected to a pipe forming a part of an additional heating circuit for circulating and heating hot water in the hot water supply circuit or the bathtub. A water level control method for detecting the water level in the bathtub by the water pressure acting on, and controlling the water level in the bathtub to a desired water level by adjusting the amount of hot water supplied to the bathtub by the detected water level. And the water level detecting means to form a closed path for selectively communicating the pipe between the bath and the water level detecting means by the valve means, and the pipe forming the closed path is the hot water in the bath. The minimum water level that is filled and the opening of the pipe of the bathtub is submerged in the hot water is used as a reference water level, and the water level in the bathtub is detected before the hot water is supplied to the bathtub. When the output means detects a lower water level than the reference water level, after performing hot water supply to the bathtub through the pipe with an amount of water sufficient to remove air in the pipe, water level detection is performed, and the water level detection means is When the water level exceeding the reference water level is detected, hot water is supplied to the bath up to the set water level.

[Action]

An appropriate set water level for the bathtub is set together with the reference water level of the bathtub into which air enters the pipe, and the water level detection means detects the reference water level or less and stores it.

At the time of water supply, only when it remembers that the detected water level has dropped to the standard water level, supplementary water is supplied through the pipe,
Next, the detected water level detected through the internal pressure of the pipe is compared with the set water level. When the detected water level is below the set water level, the water level in the bathtub is controlled to the set water level.

Therefore, in such a water level control method, when water is supplied,
If the water level has never dropped below the standard water level between the previous water supply and the next water supply, the water level can be controlled to the required water level by directly operating the main water supply without going through auxiliary water supply. Auxiliary water supply operation is selectively performed depending on whether the water level has dropped below the standard water level before, and when auxiliary water supply is not required, the air detection sequence and auxiliary sequence operation mode for auxiliary water supply are omitted. Therefore, the efficiency of control is improved.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings.

FIG. 1 shows an embodiment of the water level control method for a bath according to the present invention.

A hot water supply device 4 is installed as a water supply source for supplying desired hot water to the bathtub 2, and between the bathtub 2 and the hot water supply device 4.
Two pipes 6, 8 are provided as water supply pipes for supplying hot water from the hot water supply device 4 to the bathtub 2 or returning hot water to the hot water supply device 4 side.
Are arranged. These pipes 6 and 8 are connected to the wall surface or the bottom surface side of the bathtub 2. By the way, h _E represents a reference water level as a water level at the opening of the pipe 8 in the bathtub 2, and h _F represents a set water level as a required water level for use.

A water heater 40 is installed in the hot water supply device 4 as a first heating means for the water that has been supplied with water from the tap water pipe 10 or the like. A two-way valve 42 is installed on the hot water supply pipe 41 of the water heater 40, and when the hot water is poured by fully automatic operation, the hot water is poured from the water heater 40 side to the reheating circuit 43 side. Is a valve for.

Hot water W _{H that} has passed through the two-way valve 42 is temporarily stored in the hopper 44. The hopper 44 is a tank installed as a separating means for separating the clean water and the hot water W _H on the bathtub 2 side. The hopper 44 has a water level detection switch for detecting the water level of the hot water W _H.
SW is installed. Further, an end portion of the hot water supply pipe 41 facing the hopper 44, water control valve operated by a ball tap BT moving up and down by the water level of the hot water W _H in the hopper 44 is installed.

A first three-way valve 45A is installed on the bottom side of the hopper 44, and a pipe 8 is connected to the output side of the three-way valve 45A together with a pipe 46 leading to the pipe 6. Pump 47 and water flow switch 48 for performing circulation of hot water or hot water W _H is installed in the pipe 46, the second three-way valve 45B between the pipe 46 and the pipe 8 through these pumps 47 and running water switch 48 is set up. The three-way valve 45B is a switching valve that switches a water supply path for supplying hot water W _H to the bathtub 2 from the pipe 6 side or the pipe 8 side. The pipe 6 is connected to the three-way valve 45B, and the pipe 6 is provided with a reheating heat exchanger 49 as a second heating means to be operated at the time of reheating. Therefore, the reheating circuit 43 is configured by a circulation path including the pump 47, the reheating heat exchanger 49, and the pipes 6 and 8.

A branch pipe 12 is connected to the pipe 8 and a pressure sensor 14 as a water level detecting means for detecting the water level of the bath 2 by the pressure acting on the pipe 8. The detection signal m ₁ of the pressure sensor 14 is applied as a control input to the hot water supply control unit 16 as water level control means.

As the hot water supply control unit 16, for example, as shown in FIG. 2, a control device including a microcomputer is used. The hot water supply control unit 16 is provided with a central processing unit (CPU) 160 as an arithmetic means for performing necessary hot water supply control. The CPU 160 is connected to a read-only memory (ROM) 161 as a storage unit for storing a control program and fixed data, and an occasional write / read memory (RAM) 162 for storing data in the process of calculation and various kinds of captured data. There is. In the hot water supply control unit 16, the pressure sensor 14
1 detection signal m ₁ and various detection signals m ₂ from other sensors 50
.. _Mn is filtered by a filter (FIL) 163 to remove unnecessary components such as noise, and then selectively added to an analog-to-digital converter (ADC) 165 through a multiplexer (MPX) 164. The MPX164 and ADC165 are integrally configured as AD conversion means. Then, the detection signals m _{1 to} m _n digitized by the ADC 165 are fetched by the CPU 160, subjected to predetermined arithmetic processing in accordance with the control program written in the ROM 161, and then stored in the RAM 162. Further, control input signals V _{C1 to} V _Cn are added to the CPU 160 from a control input means such as a drive switch through an input / output circuit (I / O) 166, and each control input signal V _{C1
C1 to} V _Cn are also taken into consideration in arithmetic control as control data. Therefore, the two-way valve 42 and the three-way valve 45 are calculated by the CPU 160.
Various control output signals V _{O1 to} V _On for controlling the A, 45B, the reheating heat exchanger 49, etc. are obtained and transmitted to various control means through the input / output circuit 166.

In the above structure, the piping system for the pressure acting on the pressure sensor 14 is as shown in FIG. That is,
When the water level is detected, the hopper 44 side of the three-way valve 45A is closed, and the pipe 6 side of the three-way valve 45B is closed so that the water pressure on the bathtub 2 side acting on the pipe 8 side does not leak. In this case, the parts of the three-way valves 45A and 45B other than the pipe 8 side may be closed, and only the pipe 8 side may be opened.

Then, assuming that the water level in the bathtub 2 is h, and if air is not present in the pipe 8, the pressure distribution in the bathtub 2, the pipe 8 and the branch pipe 12 has pressures P _{1 to} P _{8 as} shown in FIG. Becomes

By the way, the pressure P ₁ is the vertical component from the water level h of the bath 2 to the pipe 8, the pressure P ₂ is the vertical component from the pipe 8 to the bottom of the bath 2, and the pressures P _{3 to} P ₈ are the vertical components in the pipe 8. The pressures P _{1 to} P ₅ are pressure components in the bathtub 2 and the pipe 8 on the bathtub 2 side, and the pressures P _{6 to} P ₈ are pressure components on the hot water supply device 4 side.

Therefore, looking at the pressures P _{1 to} P ₅ on the bathtub 2 side,
The pressure P ₄ and the pressure P ₅ are balanced between a and b of the pipe 8, and the component becomes zero. The pressure P ₂ in the bathtub 2 is the pressure exerted on the bottom of the tub 2, does not act on the pipe 8. Therefore, the pressures P ₁ and P ₃ act on the pressure sensor 14 on the bath 2 side. On the water heater 4 side, the pressure P ₇ and the pressure P ₈ are in balance, so that only the pressure P ₆ acts on the pressure sensor 14. Therefore, the pressure sensor 14 detects the pressure P ₁ on the water surface side in the bathtub 2 and the pressure in the pipe 8 filled with hot water.
Since P ₃ and P ₆ are added, there is only the height component between the pressure sensor 14 and the water surface of the bathtub 2. That is, the pressure P _S detected by the pressure sensor 14 is P _S = P ₁ + P ₃ + P ₆ (1). Therefore, this pressure P _S corresponds to the water level h,
The water level h in the bathtub 2 can be known by the detection. However, when air enters the pipe 8, the pressure drops due to the air, and the pressure sensor 14 receives a pressure indicating the water level that requires hot water supply, despite actually maintaining the predetermined water level. Will be detected.

Next, the water level control method will be described with reference to the water level control program shown in FIG.

As an initial setting, the reference water level h _E and the set water level h _F are taken in, and the reference water level h _E and the set water level h _F are stored as reference data in the RAM 162 or the external storage means of the hot water supply control unit 16 in advance. By the way, the installation positions of the bathtub 2 and the water heater 4 are
It depends on the house, but under normal construction conditions, bathtub 2
Is installed at a height of 2m underground to 4m above the ground, but bathtub 2
The reference water level h _{E at} is a reference value for water level detection and represents a water level slightly higher than the opening position of the pipe 8 of the bath 2 regardless of the height of the bath 2. Also, the set water level h _F
Is set to the water level desired by the consumer, for example. Therefore, after supplying the hot water W _H to the set water level h _F in the bathtub 2, the pressure representing the water level is detected, and the detected pressure is written as the set water level h _F in the RAM 162 or the external storage means.

Then, in step S ₁ , the water level of the bathtub 2 is detected prior to hot water supply. Next, in step S ₂ , the detected water level h _S represented by the detected pressure is compared with the reference water level h _E, and the comparison is always performed to monitor the fluctuation of the water level.

Next, in step S ₃ , the case where the detected water level h _S is lower than the reference water level h _E is stored in the RAM 162 or the external storage means.

Next, in step S ₄ , when hot water is supplied, it is determined whether or not the detected water level h _S has dropped below the reference water level h _E by referring to the RAM 162 or the external storage means.

If the detected water level h _S is not lower than the reference water level h _E , the process moves to step S ₅ , and the detected water level h _S and the set water level h _F
When the detected water level h _S is equal to the set water level h _F , the process ends.When the detected water level h _S is lower than the set water level h _F ,
In step S ₆ , hot water is supplied up to the set water level h _F.

If it is stored in the RAN 162 or the external storage means that the detected water level h _S is lower than the reference water level h _E in step S ₄ , the process proceeds to step S ₇ and the three-way valve 45A is opened to the pipe 8 side. , Auxiliary water supply from the pipe 8 side. This supplementary water supply
The amount of water supplied is such that the air in the pipe 8 can be removed.

Next, in step S _8, again, perform the water level detected by closing the three-way valve 45A.

Then, in step S ₉ , the water level detected by the pressure sensor 14
When h _S is compared with the set water level h _F, and the detected water level h _S is equal to the set water level h _F (h _S = h _F ), hot water supply control ends. Further, in step S _9, and the detection level h _S is shifted to step S ₁₀ if it is judged to be lower than the set water level h _F, the water level in the step S ₁₀ in tub 2 reaches the set water level h _F hot water To complete the water level control.

By the way, for hot water supply, when the water heater 40 is operated, for example, the three-way valve 45A is switched to the pipe 46 side, the three-way valve 45B is switched to the pipe 6 side, and the pump 47 is operated, the hot water W supplied to the hopper 44 is supplied. _H is a three-way valve 45A, piping 46, pump 4
7, supplied to the bathtub 2 through the three-way valve 45B and the pipe 6, the hot water W _{H in the} bathtub 2 is an optimum preset water level h _F set in advance.
Is controlled.

〔The invention's effect〕

As described above, according to the present invention, when performing automatic hot water filling by constantly monitoring the water level, it is determined whether or not the water level of the bathtub has dropped to the reference water level after the end of the last hot water filling operation. However, if the water level in the bathtub does not drop below the standard water level, normal supply control is performed, and only if the water level in the bathtub drops below the standard water level, perform auxiliary water supply and then detect the water level again. Since the hot water supply control is performed and the required hot water supply control is performed, the efficiency of the hot water supply control can be improved, and the hot water can be quickly supplied to the bathtub.

[Brief description of drawings]

FIG. 1 is a piping system diagram of a water level control system showing an embodiment of a water level control method for a bathtub according to the present invention, and FIG. 2 is a specific configuration example of a hot water supply control unit in the water level control system shown in FIG. Block diagram shown in FIG. 3, FIG. 3 is a diagram showing a pressure detection system in the water level control system shown in FIG. 1, FIG. 4 is a diagram showing pressure distribution in the water level control system shown in FIG. 1, and FIG. It is a flow chart which shows the water level control program of the water level control system shown in FIG. 2 ... Bathtub 4 ... Hot water supply device (water supply source) 6, 8 ... Piping 14 ... Pressure sensor (water level detection means) 16 ... Hot water supply control unit (water level control means)

Claims (1)

(57) [Claims] 1. A water level detecting means is connected to a pipe forming a part of an additional heating circuit for supplying hot water to a bathtub through a hot water supply circuit and circulating hot water in the hot water supply circuit or the bathtub to act on the pipe. A water level control method for detecting a water level in the bathtub by water pressure, controlling the water level in the bathtub to a desired water level by adjusting the amount of hot water supplied to the bathtub by the detected water level, wherein the bathtub and the A closed path is formed to selectively connect the pipe connecting the water level detection means to the water level detection means between the bathtub and the water level detection means, and the pipe forming the closed path is filled with the hot water in the bathtub. And, the minimum water level at which the opening of the pipe of the bathtub is submerged in the hot water is used as a reference water level, and the water level in the bathtub is detected before the hot water is supplied to the bathtub. When the stage detects a lower water level than the reference water level, after supplying hot water to the bath through the pipe with an amount of water that can remove the air in the pipe, the water level is detected, and the water level detection means is A water level control method for a bathtub, which comprises supplying water to the bathtub up to a set water level when a water level exceeding a reference water level is detected.