JP2002035515A - Bathtub water cleaning apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bathtub water cleaning apparatus capable of being enhanced in its operational reliability by reducing the number of solenoid valves and capable of being made small-sized and inexpensive. SOLUTION: The bathtub water cleaning apparatus is constituted so that a circulating pump 4 and a filter for diltering a contaminant in bathtub water 2 are provided to a circulating route A for circulating bathtub water 2 in a bathtub 1 and a branch route B is provided so as to be arranged in parallel to the circulating route A reaching a filter from the circulating pump 4 and a sterilizing solution supply device X is provided in the branch route B to supply the sterilizing solution stored in sterilizing solution supply device X to the circulating route A on the primary side of the filter. A first throttling part 5 is provided to the circulating route A at the position which is on the downstream side of the branch position on the inflow side of the branch route B and on the upsteam side of the confluent position on the outflow side of the branch route B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bathtub water purifying apparatus provided with a function of removing suspended substances and general bacteria in bathtub water.

[0002]

2. Description of the Related Art A conventional bathtub water purifier is configured as shown in FIG. The bathtub 1 is provided with a suction / water discharge port 3 composed of a suction / water discharge unit, and a circulation path A for circulating the bath water 2 of the bathtub 1 is provided. The bath water absorbed from the water suction side of the suction / water discharge port 3 is provided. 2 is circulated through the circulation path A to discharge water into the bathtub 1 from the water discharge side of the suction / water discharge port 3. A circulation pump 4 that is driven when the bathtub water 2 is circulated is disposed in the circulation path A. The circulation path A is composed of a first circulation path A1 and a second circulation path A2 branched from the first circulation path A1 on the downstream side of the circulation pump 4 and the first circulation path A1 and the second circulation path A2. The end on the water discharge side of the circulation path A2 is communicated with the water discharge side of the suction / water discharge port 3. A filtration tank 8 is disposed in the middle of the first circulation path A1,
The filtration tank 8 has a hollow fiber membrane 9 as a filter. A heater 13 is interposed in the second circulation path A2, and the heater 13 can heat the bathtub water 2 circulating in the second circulation path A2.

[0003] A branch path B branched from the circulation path A is provided at a portion of the circulation path A between the circulation pump 4 and the filtration tank 8, and the inflow end of the branch path B is connected to the second circulation path A.
2, and the end of the branch path B on the outflow side is connected to the first circulation path A1 on the primary side of the filtration tank 8.
A germicidal solution supply device X is arranged in the branch path B. The disinfecting solution supply device X includes a salt dissolving tank 11 and an electrolytic electrode tank 12, and the salt dissolving tank 11 and the electrolytic electrode tank 12 are arranged in parallel. The filtration tank 8 and the upstream side of the circulation pump 4 of the circulation path A are communicated with each other through the cleaning path C, and the drainage path D is branched from the middle of the cleaning path C.

A first circulation path A1 and a second circulation path A2
An on-off valve 5 'made of a solenoid valve is disposed in the first circulation path A1 at a position downstream of the branch position of the above and at a position upstream of the merging position on the outflow side of the branch path B. An opening / closing piece 6 ′ made of a solenoid valve is disposed in the second circulation path A 2 at a position downstream of the branch position between the second circulation path A 2 and the inflow side of the branch path B and upstream of the heater 13. I have. At the position downstream of the filtration tank 8, the first circulation path A1
Is provided with an on-off valve 7 composed of a solenoid valve. A switching valve 14 composed of an electric disk valve is disposed at a branch portion between the cleaning path C and the drain path D. An electric ball valve is provided between the salt dissolving tank 11 and the electrolytic electrode tank 12 of the sterilizing solution supply device X. The switching valve 10 is disposed.

FIG. 9 shows a state in which the bathtub water 2 is being purified. In this state, the on-off valves 5 ', 6' and 7 are open, and the switching valve 10 is on the salt dissolving tank 11 side and the electrolytic electrode tank 12 side. Both are closed, the switching valve 14 is closed on both the pump side and the drain side,
The circulation pump 4 is driven. By driving the circulation pump 4, the bathtub water 2 is sucked up from the water suction side of the water inlet / outlet port 3, and is divided into the first circulation path A1 and the second circulation path A2. When the bathtub water 2 circulating through the first circulation path A1 passes through the filtration tank 8, the bathtub water 2 flows through the hollow fiber membrane 9 in the filtration tank 8.
Fine suspended matter, fungi, fungus dead, and the like are removed, and the filtered bathtub water 2 is discharged into the bathtub 1 from the water discharge side of the suction / water discharge port 3. Further, the bathtub water 2 flowing through the second circulation path A2 is heated by the heater 13, and the heated bathtub water 2 is absorbed and absorbed.
Water is discharged into the bathtub 1 from the water discharge side of the water discharge port 3.

When the hollow fiber membrane 9 as a filter is washed, the on-off valve 5 'is opened and the on-off valves 6' and 7 are closed, and the switching valve 14 is opened on the pump side and closed on the drain side. Can be switched to When the circulation pump 4 is driven in this state, the bath water 2 is sent from the circulation pump 4 to the filtration tank 8 via the first circulation path A1, and the cleaning path C
Bath water 2 so that bath water 2 returns to circulation pump 4
Circulates, and the hollow fiber membrane 9 as a filter of the filtration tank 8 is washed. In this state, the switching valve 14 is closed to the pump side and opened to the drain side, and the bathtub water 2 that has contributed to the cleaning is drained through the drain path D.

When the sterilizing solution is supplied, the on-off valve 7 is open, the on-off valves 5 'and 6' are closed, the switching valve 10 is closed on the salt dissolving tank 11 side, and open on the electrolytic electrode tank 12 side. The switching valve 14 is closed on both the pump side and the drain side. When the circulation pump 4 is driven in this state, a pressure difference is generated between the primary side and the secondary side of the sterilizing solution supply device X, and the sterilizing solution in the electrolytic electrode tank 12 is supplied to the hollow fiber membrane 9 as a filter. . When the saline solution is supplied to the electrolytic cell 12, the switching valve 10 is opened toward the salt dissolving tank 11 in the above state,
And the circulation pump 4 is intermittently driven for a short period of time so that the salt dissolution tank 11
2 is supplied with a predetermined amount of saline. Thereafter, in the normal circulation operation, the on-off valves 6 ′ and 7 each composed of an electromagnetic valve are once opened, but the on-off valves 6 ′ and 7 each composed of an electromagnetic valve are closed by the water head pressure, and the saline solution is excessively injected by the water head pressure. Has been prevented.

[0008]

By the way, in the above-mentioned conventional example, an electric disc valve as the switching valve 14,
In addition to the electric ball valve as the switching valve 10, a large number of solenoid valves are used as the on-off valves 5 ', 6', and 7.
However, the solenoid valve has drawbacks such as dust floating in the bathtub water 2, sealing failure due to biting of hair, voltage fluctuation, operation failure due to coil temperature rise, and the like. There is a problem that the performance is reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above description, and provides a bathtub water purification apparatus which can reduce the number of solenoid valves, improve the reliability of operation, and can be reduced in size and cost. That is the task.

[0010]

In order to solve the above-mentioned problems, a bathtub water purifying apparatus of the present invention comprises a circulation path A for circulating bathtub water 2 in a bathtub 1 through a circulation pump 4 and contaminants in the bathtub water 2. Is provided, a branch path B is provided in parallel with a circulation path A from the circulation pump 4 to the filter, and a germicidal solution supply device X is interposed in the branch path B. In the bathtub water purification device in which the germicidal solution stored in the tub is supplied to the circulation path A on the primary side of the filter, the bactericidal solution is located at a position downstream of the branch position on the inflow side of the branch path B and in the branch path B. A first throttle section 5 is provided in the circulation path A at a position upstream of the merging position on the outflow side. By providing the first throttle unit 5 as described above, it is possible to supply a sterilizing solution from the sterilizing solution supply device X by creating a pressure difference between the primary side and the secondary side of the sterilizing solution supply device X. It is possible to reduce the number of solenoid valves as an on-off valve conventionally provided for supplying a sterilizing solution from the sterilizing solution supply device X. Since the number of solenoid valves can be reduced in this way, reliability can be improved, and the size can be reduced and the cost can be reduced by using a throttle instead of the solenoid valve.

The circulation path A is connected to the circulation pump 4
Circulation path A from the filter to the bathtub 1 via the filter
1 and a second circulation path A2 that branches off from the first circulation path A1 and reaches the bathtub 1 without passing through a filter. The second circulation path A2 is a branch point from the first circulation path A1. It is also preferable that the second throttle section 6 is provided at a position further downstream.

It is also preferable that the first and second throttle portions 5 and 6 are formed integrally with the pipe P of the pipe.

Further, check valves 16 and 17 which are closed when the circulation of the bathtub water 2 is stopped are provided on the side of the circulation path A sucked by the circulation pump 4 and on the discharge side of the second circulation path A2. Is also preferred.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIGS.
Is provided with a suction / water discharge port 3 composed of a suction / water discharge unit, and a circulation path A for circulating the bath water 2 of the bathtub 1 is provided. The bath water 2 absorbed from the water suction side of the water suction / water discharge port 3 is provided. The bathtub 1 is circulated through the circulation path A from the water discharge side of the suction / water discharge port 3.
Water is spouted inside. A circulation pump 4 driven when circulating bathtub water is arranged in the circulation path A. The circulation path A is composed of a first circulation path A1 and a second circulation path A2 branched from the first circulation path A1 on the downstream side of the circulation pump 4, and the first circulation path A1 and the second circulation path A2. The end on the water discharge side of the circulation path A2 is communicated with the water discharge side of the suction / water discharge port 3. A filtration tank 8 is arranged in the middle of the first circulation path A1, and the filtration tank 8 has a hollow fiber membrane 9 as a filter. A heater 13 is interposed in the second circulation path A2, and the heater 13 can heat the bathtub water 2 circulating in the second circulation path A2.

A branch path B branched from the circulation path A is provided at a portion of the circulation path A between the circulation pump 4 and the filtration tank 8, and an inflow end of the branch path B is located downstream of the circulation pump 4. At a position upstream of the branch between the first circulation path A1 and the second circulation path A2, and the end of the branch path B on the outflow side is the primary side of the filtration tank 8. Side is connected to the first circulation path A1. A germicidal solution supply device X is arranged in the branch path B. The disinfecting solution supply device X includes a salt dissolving tank 11 and an electrolytic electrode tank 12, and the salt dissolving tank 11 and the electrolytic electrode tank 12 are arranged in parallel. The electrolytic electrode tank 12 is configured to generate sodium hypochlorite having a sterilizing effect by electrolyzing a saline solution. The salt dissolving tank 11 supplies a salt solution in which salt is dissolved. The filtration tank 8 and the upstream side of the circulation pump 4 of the circulation path A are communicated with each other through the cleaning path C, and the drainage path D is branched from the middle of the cleaning path C.

A first circulation path A1 and a second circulation path A2
A first throttle unit 5 is provided in the circulation path A at a position on the upstream side of the branch position between the first path and the downstream side of the branch position on the inflow side of the branch path B. In the second circulation path A2 at a position downstream of the branch position with the second circulation path A2 and upstream of the heater 13, the second throttle unit 6 is provided.
Is provided. The first throttle portion 5 and the second throttle portion 6 are integrally provided on the inner surface side of the pipe P of the pipe constituting the circulation path A as shown in FIG. That is,
An annular flange is provided integrally so as to reduce the inner diameter of the pipe P. In FIG. 7, D is the pipe inner diameter, and D 'is the throttle diameter.

An on-off valve 7 composed of a solenoid valve is arranged in the first circulation path A1 at a position downstream of the filtration tank 8. The second circulation path A2 is provided with an on-off valve 20 composed of an electromagnetic valve at a position downstream of the heater 13. A switching valve 14 composed of an electric disk valve is disposed at a branch portion between the cleaning path C and the drain path D. An electric ball valve is provided between the salt dissolving tank 11 and the electrolytic electrode tank 12 of the sterilizing solution supply device X. The switching valve 10 is disposed.

A check valve 16 that closes when the circulation of the bathtub water 2 is stopped is provided at an end of the circulation path A on the water suction side near the suction / water discharge port 3 so that the suction and discharge of the second circulation path A2. A check valve 17 that closes when circulation of the bathtub water 2 is stopped is provided at an end on the water discharge side near the water discharge port 3. Check valve 16 is shown in FIG.
(B) As shown in (b) ', a valve body 22 is provided in the valve chamber 21 of the pipe P so as to be vertically movable, and a valve seat 23 on the lower surface side of the valve chamber 21 is opened and closed by the vertical movement of the valve body 22. The valve body 22 is urged downward by a spring 24 provided in the valve chamber 21. In the circulating stop state, the valve seat 23 is closed as shown in FIG. 8 (b), and in the circulating state, the valve body 22 is moved upward with respect to the valve seat 23 against the spring 24 as shown in FIG. 8 (b) '. It is designed to be separated. The check valve 17 is shown in FIG.
As shown in (a) ′, a valve body 22 is provided in a valve chamber 21 of a pipe P so as to be vertically movable, and a valve seat 2 on the upper surface side of the valve chamber 21 is provided.
The valve body 3 is opened and closed by the vertical movement of the valve body 22, and the valve body 22 is urged upward by a spring 24 provided in the valve chamber 21. In the circulating stop state, the valve seat 23 is closed as shown in FIG. 8A, and in the circulating state, the valve body 22 is lowered against the valve seat 23 against the spring 24 as shown in FIG. It is designed to be separated.

An air bleeding path E is connected to the uppermost portion of the circulation path A between the primary side of the circulating pump 4 and the water suction side of the suction / water discharge port 3. A stopper 15 is provided.

FIG. 1 shows a state in which bath water is purified. The on-off valves 7 and 20 are open, the switching valve 10 is closed on both the salt bath dissolution tank 11 side and the electrolytic electrode tank 12 side, and the switching valve is closed. 1
Numeral 4 indicates that both the pump side and the drain side are closed. When the circulating pump 4 is driven in this state, the circulating pump 4 draws up the bathtub water 2 in the bathtub 1 from the suction side of the water inlet / outlet port 3 and divides the bathtub water 2 into the first circulation path A1 and the second circulation path A2. Can be Second
The bathtub water 2 flowing through the circulation path A2 is heated by the heater 13, and the heated bathtub water 2 is discharged from the water discharge side of the suction / water discharge port 3 and returned to the bathtub 1. Also, the first circulation path A
The bathtub water 2 flowing through 1 passes through a filtration tank 8 and is filtered by a hollow fiber membrane 9 as a filter. Then, the filtered bathtub water 2 is discharged from the water discharge side of the suction / water discharge port 3 and returned to the bathtub 1. . Fine suspended matter, fungi and dead fungi in the bath water 2 are removed by filtration through the hollow fiber membrane 9 serving as the filter. At this time, since the second throttle portion 6 is arranged in the second circulation path A2, a filtration flow rate necessary for maintaining the purification performance even when the hollow fiber membrane 9 is clogged can be secured. Also the first
The two systems of the circulation path A1 and the second circulation path A2 are provided in accordance with the change in the flow rate passing through the hollow fiber membrane 9 in order to maintain the hot water temperature by the heater 13 and to stir the bathtub water 2. This is to ensure the circulation flow rate.

Table 1 below shows the relationship between the second throttle section 6 and the circulation flow rate in the two systems. At this time, the inner diameter D of the pipe P shown in FIG. 7 is 15 mmφ, and the diameter D ′ is changed.

[0022]

[Table 1]

According to the results shown in Table 1, when the throttle diameter is reduced, the filtration flow rate increases, but the total circulation flow rate tends to decrease.
Therefore, it can be seen that the filtration flow rate cannot be secured when the hollow fiber membrane 9 is clogged without the restriction. Also, by changing the diameter of the throttle, it is possible to secure a filtration flow rate that can maintain the purification performance.

FIG. 2 shows a state of the hollow fiber membrane 9 as a filter when the membrane is washed. The on-off valves 7 and 20 are closed, and the switching valve 10 is closed on both the salt bath dissolution tank 11 side and the electrolytic electrode tank 12 side. The switching valve 14 is open on the pump side and closed on the drain side. At this time, the bathtub water 2 is supplied into the filtration tank 8 via the circulation pump 4 by driving the circulation pump 4, and the bathtub water 2 is discharged from the ejection port of the washing nozzle 18 to remove the deposits on the hollow fiber membrane 9. It is physically separated and returned from the filtration tank 8 to the circulation pump 4 again via the cleaning path C. At this time, the cleaning nozzle 18 rotates by the circumferential force of the jet flow, and cleans the entire circumference of the hollow fiber membrane 9.

FIG. 3 shows a state at the time of drainage.
After the completion of the membrane cleaning, the pump side of the switching valve 14 is closed, and the drain side is opened. At this time, the bath water 2 is supplied to the filtration tank 8 by the circulation pump 4 so that the washing water suspended by the washing is discharged from the bottom of the filtration tank 8 to the outside of the bath 1 via the switching valve 14 through the discharge path D. Is discharged.

FIG. 4 shows a state in which the sterilizing solution is supplied, the on-off valves 7 and 20 are open, the switching valve 14 is on the pump side,
The drainage side is closed, and the switching valve 10 is closed on the salt dissolving tank 11 side and open on the electrolytic electrode tank 12 side. At this time, the bath water 2 is supplied to the electrolytic electrode tank 12 by the circulation pump 4, and the sterilizing solution stored in the electrolytic electrode tank 12 is extruded, and the sterilizing solution is supplied to the filtration tank 8, and the hollow fiber membrane 9 is formed. Sterilized.
Further, the bactericidal solution that has reached the bathtub 1 sterilizes the bathtub water 2 and simultaneously sterilizes the inside of the system with the circulating bathtub water 2 to prevent the growth of bacteria in the system, the bathtub water 2 and the bathtub 1. I have. At the time of supplying the sterilizing solution, the first throttle section 5 obtains a pressure difference between the primary side and the secondary side of the electrolytic electrode tank 12 of the sterilizing solution supply device A to supply the sterilizing solution. .

FIG. 5 shows the state of priming of the circulation pump 4. At this time, the on-off valves 7 and 20 are closed, the switching valve 10 is closed on both the salt bath dissolution tank 11 side and the electrolytic electrode tank 12 side, and the switching valve 14 is closed on both the pump side and the drainage side.
In the case of a non-self-contained pump, if there is an air pocket in the path on the suction side of the pump, the pump is in an idling state and the bathtub water 2 cannot be circulated. Therefore, it is necessary to eliminate the air accumulation in the path on the suction side of the pump at the time of priming. When priming water from the filtration tank 8, the inside of the circulation pump 4 is first filled with water pressure. At this time, the air vent plug 15 is removed, and the air in the path is discharged to the atmosphere. By eliminating the air pool as described above, the idling of the circulation pump 4 can be prevented. However, the condition is that the check valves 16 and 17 are submerged in the bath water 2 of the bath 1. In addition, by arranging the water suction side and the water discharge side of the circulation pump 4 on the top surface of the circulation pump 4, it is possible to prevent air from accumulating in the circulation pump 4.

FIG. 6 shows a state when the saline solution is supplied. At this time, the on-off valve 7 is open, the on-off valve 20 is closed, the switching valve 14 is open on the pump side, the drain side is closed, and the switching valve 10 is open on the salt dissolution tank 11 side and closed on the electrolytic electrode tank 12 side. is there. In this state, the circulation pump 4 is intermittently operated for a short time to supply a predetermined amount of the saline solution in the salt dissolving tank 11 to the electrolytic electrode tank 12. When the supply of the saline solution is completed, the circulation pump 4 is stopped, and the check valves 16 and 17 are both closed. At this time, since the check valves 16 and 17 are closed, it is possible to prevent the saline solution from being excessively injected due to the negative head pressure.

[0029]

According to the first aspect of the present invention, a circulation path for circulating bath water in a bath is provided with a circulation pump and a filter for filtering contaminants in the bath water, and a circulation path from the circulation pump to the filter. And providing a branch path arranged in parallel with the sterilizing solution supply device in the branch path,
In a bath water purifier configured to supply the germicidal solution stored in the germicidal solution supply device to the circulation path on the primary side of the filter, at a position downstream of the branch position on the inflow side of the branch path and at a branch. Since the first throttle portion is provided in the circulation path at a position upstream of the merging position on the outflow side of the path, a pressure difference is created between the primary side and the secondary side of the sterilizing solution supply device to supply the sterilizing solution. It is capable of supplying a germicidal solution from the device, and can reduce the number of solenoid valves as an open / close valve provided for supplying a germicidal solution from a conventional germicidal solution supply device, The reliability can be improved by reducing the number of solenoid valves, and the size and cost can be reduced by using a throttle instead of the solenoid valves.

[0030] The invention of claim 2 of the present invention is based on claim 1.
In the above, the circulation path is divided into a first circulation path from the circulation pump to a bathtub through a filter, and a second circulation path from the first circulation path to a bathtub without a filter.
Since the second throttle section is provided at a position downstream of the branch point from the first circulation path in the second circulation path, the diameter of the second throttle section is changed. Thus, the filtration flow rate passing through the filtration tank can be adjusted, and the filtration flow rate at which the purification performance can be maintained even when the filter is clogged can be ensured.

Further, the invention of claim 3 of the present invention is directed to claim 2
In the above, since both the first and second throttle portions are formed integrally with the pipe of the pipe, they can be easily provided so as not to obstruct the throttle portion, and a space-saving and inexpensive system configuration can be realized. It is.

The invention of claim 4 of the present invention provides the method of claim 2
In the above, a check valve that closes when circulation of bath water is stopped is provided on the side of the circulation path sucked by the circulation pump and on the water discharge side of the second circulation path. Therefore, it is possible to prevent the saline solution from being excessively charged due to the head pressure without using an electromagnetic valve which is closed by the head pressure.

[Brief description of the drawings]

FIG. 1 is a route diagram of a state during purifying bathtub water according to an example of an embodiment of the present invention.

FIG. 2 is a path diagram in a state at the time of membrane cleaning according to the first embodiment.

FIG. 3 is a route diagram in a state at the time of drainage of the above.

FIG. 4 is a path diagram of a state when the sterilizing solution is supplied.

FIG. 5 is a route diagram in a state of priming according to the first embodiment.

FIG. 6 is a path diagram in a state at the time of supplying a saline solution according to the embodiment.

FIG. 7 is a cross-sectional view illustrating an aperture unit according to the third embodiment.

FIG. 8 is a cross-sectional view illustrating the structure of the check valve according to the first embodiment;
(A) and (b) are in a stopped state, and (a) '(b)' is in a circulating state.

FIG. 9 is a path diagram in a state at the time of bathtub water purification of a conventional example.

[Explanation of symbols]

 Reference Signs List 1 bathtub 2 bathtub water 4 circulation pump 5 first throttle unit 6 second throttle unit 8 filtration tank 16 check valve 17 check valve A circulation path A1 first circulation path A2 second circulation path B branch path X Disinfectant solution supply device

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C02F 1/50 520 C02F 1/50 540B 540 550C 550 550D 560F 560 560Z B01D 35/02 JF Term (Reference) 4D006 HA01 KB30 KC01 KC02 KC21 KD24 PA01 PB07 PB24 PB70 PC56 4D064 AA11 BF32 BF33 BF34 BF36 BF39 BF40

Claims (4)

[Claims] 1. A circulation path for circulating bathtub water in a bathtub is provided with a circulation pump and a filter for filtering contaminants in the bathtub water, and a branch path is provided in parallel with a circulation path from the circulation pump to the filter. A tubing water purification device in which a germicidal solution supply device is interposed in the branch path and the germicidal solution stored in the germicidal solution supply device is supplied to the circulation path on the primary side of the filter. A bathtub water purification device, wherein a first throttle portion is provided in the circulation path at a position downstream of a branch position on an inflow side and upstream of a junction position on a discharge side of a branch path. 2. A first circulation path from the circulation pump to a bathtub through a filter, and a second circulation path from the first circulation path to a bathtub without a filter. 2. The bathtub water purifying apparatus according to claim 1, wherein a second throttle portion is provided in the second circulation path at a position downstream of a branch point from the first circulation path. 3. The bathtub water purifier according to claim 2, wherein both the first and second throttle portions are formed integrally with the pipe. 4. A check valve which closes when circulation of bathtub water is stopped is provided on a side of the circulation path sucked by the circulation pump and on a water discharge side of the second circulation path. The bathtub water purification device according to 2.